Saturday, May 12, 2018

GEOGRAPHY: FORM FOUR: Topic 5 - ENVIRONMENTAL ISSUES AND MANAGEMENT



TOPIC 5: ENVIRONMENTAL ISSUES AND MANAGEMENT

The Meaning of Environment

Environment is the total of all surroundings of man, including nonliving things, natural forces and other living things. Or, Environment is all of the natural materials and living things, including sunlight. If those things are natural, it is a natural environment.

So you can see that environment is everything that is around us. It can be living or nonliving things. It includes physical, chemical and other natural forces. Living things live in their environment. They constantly interact with the environment and change in response to conditions in their environment. There are interactions between animals (including humans), plants, soil, water, and other living and non-living things.

Since everything is part of the environment of something else, the word ‘environment’ is used to talk about many things. People in different fields of knowledge (like history, geography or biology) use the word environment differently.

THE IMPORTANCE OF ENVIRONMENT

Environment is the key for existence of life on the Earth. All living organisms on Earth depend on the environment for survival. We should always strive to manage and conserve our environment. It matters because Earth is the only home that humans have, and it provides air, food, and other needs. The environment is important for the following reasons:

1. General life support

The environment contains all the resources which sustain life. These resources include soil, air, and water. The soil contains water and mineral nutrients which support plants on which humans and other animals feed. Without soil there would be no food. Even the animals that are eaten by man such birds, cattle, etc. feed on plants that grown on the soil. The increasing human population need food to survive. It is therefore important to ensure the soil is productive enough to produce enough food to feed the ever-increasing human population.

Air, as a part of the environment is needed by all organisms on Earth, including those that we cannot see with our naked eyes (microorganisms). Air is essential for life and no organism can survive without it. A constant supply of fresh air is very important though in recent years, air pollution has been a big problem, especially in heavily industrialized countries. Air pollution denies us clean air and also makes the Earth excessively hot, a condition known as global warming.

2. Natural beauty

Another reason the environment is so important is because it is a source of natural beauty. People enjoy nature for recreation, tourism, and sports such as skiing in snow or rafting. The physical landscape, drainage features, plants and animals are beautiful to look at in their natural settings. Nature is considered necessary for proper physical and mental health too.

Unfortunately the planet is in danger. Many species of animals and plants are nearing extinction, and more and more beautiful, open spaces are disappearing as new buildings and factories are built.

3. Natural resources

The environment contains diverse natural resources. The most important natural resources and products derived from the environment include the following:
a) Water - Water is an important resource needed for survival of all living organisms.
b) Medicines - Many plants have been used as medicines for hundreds of years, and are even now exploited by modern pharmaceuticals.
c) Clothing - Clothes are produced from plants like wood pulp, cotton, hemp, jute or animal products like silk, wool, and leather. In addition, synthetic clothes are produced from petroleum products.
d) Wood - Wood from forests or plantations is used as fuel, in construction and for making furniture.
e) Biofuels - Biofuels, like bioethanol, are extracted from wheat, corn or biomass crops like jatropha.
f) Fossil fuels - Fossil fuels, such as coal, gas and crude oil used in transportation, energy generation and production of plastics and chemicals, depend on dead plant and animal biomass produced by previous ecosystems that are stored and accumulated over millions of years on Earth.

4. Quality of air

Trees produce oxygen during photosynthesis. In addition, during this process trees also use carbon dioxide in the air and reduce its concentration in the atmosphere. This process regulates and maintains the carbon cycle. Trees can also remove pollutants from the air.




ENVIRONMENTAL PROBLEMS

Environmental problems refer to known processes (such as resource consumption) that have negative effects on the sustainability of the environmental quality necessary for the well being of the organisms living in it. Some scholars define environmental problems as problems caused by environmental changes due to human activities that greatly endanger the well-being of humans and the balance of our ecosystem. The main environmental problems facing the Earth include the following:
1. Pollution 
2. Overpopulation
3. Global warming
4. Waste disposal 
5. Climate change
6. Loss of biodiversity
7. Desertification
8. Ocean acidification
9. Ozone layer depletion
10. Acid rain
11. Natural disasters
12. Overgrazing

The Causes, Extent and Effects of Pollution and Waste Mismanagement

Pollution is the introduction of contaminants into the natural environment that causes adverse change. Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.

Waste management or waste disposal includes all the activities and actions required to manage waste from its creation to its final disposal. This includes, amongst other things, collection, transport, treatment and disposal of waste together with monitoring and regulation. It also includes the legal and regulatory framework that relates to waste management.

The term normally relates to all kinds of waste, whether generated during the extraction of raw materials, the processing of raw materials into intermediate and final products, the consumption of final products, or other human activities. Waste management is intended to reduce adverse effects of waste on health, the environment or aesthetics.

Waste management practices are not uniform among countries (developed and developing nations); regions (urban and rural area), and sectors (residential and industrial).

ENVIRONMENTAL POLLUTION

Environment pollution is the introduction or addition of any substance or situation that is harmful or not required to the environment i.e. Addition of unwanted material into environment. These are substance or materials that caused pollution i.e. Pollutant are material that pollute environment.

Factors which Lead to the Increase of Environmental Pollution

1. Rapid pollution growth in the world especially in the thirds world countries this led to the increase rate of production of waste and problem in the managing of the waste.

2. The increase level of poverty in the developing country. This made people uses cheap energy resources that cause air pollution like charcoal and fuel wood. Rapid advance in technology that has led to the development of supplicated industries which emits a lot of gases and waste

3. Development of transport network that has net to the development and increase number of cars that emits a lot of fumes smokes.

4. Increase in political conflict that forces people to keep on migrating from place to place end up polluting the environment as well as the use of bombs and nuclear weapons.

5. Advancement of Science and Technology.

Classification of Environmental Pollution

Environment pollution can be classified as follows
a) Air pollution
b) Soil/land pollution
c) Water pollution
d) Noise pollution.

a) AIR POLLUTION

Is an addition of waste material into air, Air is an important resource in sustaining life, without it there would be no life on earth. It is a mixture of gases surrounding the earth. These gases are such as nitrogen, oxygen carbon dioxide and others gases.

Air Pollution

Causes of Air Pollution

a) Natural Causes

1. Volcanic eruption. That gives out dust ashes and gaseous like sulphur and carbon dioxide.

2. Wind, that raise the dust and pollen to a certain levels. Dust has chemical that are toxic and hence harmful to the living organism both flora and fauna.

b) Human Causes

3. Industrial activities and automobile. This process led to the emission of fumes and gases that pollute the air.

4. The uses of charcoal, coal, firewood and fuel oil for difference purpose like cooking, lighting, smelting etc. pollute environment.

5. Construction activities. The construction of project like road construction, salting up buildings and etc. lead to introduction of dust into the air.

6. Agricultural activities pollute the air through: Digging in the soil that raises dust into air. Spraying some chemicals like insecticides.

7. Mining activities: this in also led to the introduction of dust and some gases into the atmosphere.

Effects of Air Pollution

1. Reduction in amount of solar energy because of being blocked by the layer of dusts or fumes hanging in the atmosphere leading to problems in photosynthesis.

2. Transportation in plants in upset since the smoke and dust setting on the leaves block the stomata.

3. Occurrence of global warming as the result of trapping of heat energy from the sun by the green houses gases.

4. Death of plants and animals due to poisonous gases.
5. Destruction of Ozone layer.
6. Reduction of air dirty.

7. Occurrence of acidic rainfall when gases like carbon dioxide and sulphur dioxide mix with rainfall.

8. It can causes bad and irritating smell keeping people in residence area uncomfortable.

9. It can causes dangerous disease like skin cancer.

Air Pollution

Measures towards Reducing Air Pollution

1. Planting trees which absorb gases like carbon dioxide and prevent fast movement of air that lead to the introduction of dust into the atmosphere and destruction of Ozone layer.

2. Improving the combination system in the engines so that fuel can burn easily.
3. Reducing number of small cars or industries.

4. Finding out alternative sources of energy instead of depending on the charcoal, fire wood, and fuel wood.

5. Government policies should be active and strict laws should be passed to ensure proper management of resources.

6. Land filling when dumping the wastes so that when they decompose they cannot lead to the emission of gases like methane into the Atmosphere

B) SOIL POLLUTION

Soil pollution is the process of introducing or adding any unwanted material in the soil. or Is the process of adding harmful material into the soil or earth surface which then led to the loss of soil fertility.

Soil Pollution

Sources of Soil Pollution

The main causes of soil pollution can be categorized as follows

1. From the atmosphere: the pollutants are introduced into the soil through the acidic rain. Acid rain leads to the increase of acidity into the soil which later on destroy the soil structure. Acidic rain is predominant in the industrialized countries like Germany Eastern Canada and USA.

2. From the industries: Some chemical such as radioactive material and metals can be introduced into the soil and render the soil units for Agriculture.

3. From the home steeds: Some waste from homes like bottles, metallic material plastics baby’s cans etc. which are dumped into the soil they lead to soil pollution.

4. From the farms: There are chemicals which include pesticides like DDT crop remains and fertilizers when all these chemicals get into the soil they lead to the soil pollution. Likewise irrigation activities can lead to soil pollution especially when applied in steep slope areas for a long period of time.

5. Mining activities: On the other hands mining activities can lead to the introduction of some rocks. Fragments into the upper layer of the soil which then leads to the soil pollution

Effects of Soil Pollution

1. Death of animals (Biota) since some chemicals affect plant and animal cell for instance organism like bacteria which are mainly used for decomposition of some materials to form Humus.

2. Decline in Agriculture as a results of poor production caused by poor plant growth. Poor plant growth takes place due to the decline in soil fertility in turn to the occurrence of famine which leads to the poor health and death of people.

3. It can lead to water logging and flooding because of poor drainage caused by the soil pollution which tends to create an impermeable layer of substance in the soil.

4. Change in soil structure as some of the mineral and nutrients are dissolved by acidic materials.

5. Migration of people to other areas which have not been affected by soil erosion.

6. Change in soil color which causes problems in the soil classification and determination of land uses.

Soil Pollution

Measures to be Taken in order to Reduce the Rate of Soil Pollution

1. Reducing or stopping the uses of chemicals in agriculture like DDT and used killers.
2. Increase of manure instead of industrial fertilizers.

3. Recycling of wastes rather than dumping them in the soil.

4. Launching afforestation and reforestation programmers which can reduce soil erosion.

5. Control of population so as to reduce the rate of production of wastes that lead to the pollution of soil. Population control can be done through family planning.

6. Educating people on how to undertake their activities properly.

7. Radioactive materials should be dumped so deep in the ground. Method like crops rotation use of organic manure and switch the traditional system like shifting cultivation.

8. Formulating strict policies that govern on how to dump the wastes. Fines and punishment should be impressed those who dump the waste randomly.

C) WATER POLLUTION

Water pollution; Refers to the addition or introduction of unwanted materials or substances in the water which has negative effect of animal and plant. Polluted water is not fit for human consumption like drinking unit treated first.

Water Pollution

Ways through which Water can be Polluted

1. Disposal of untreated sewage into the water bodies. The sewage can be form homestead. Institution like schools, hotels and hospitals.

2. Dumping of wastes from industries into the water bodies these can be either liquid or solid form.

3. Some chemicals and other wastes from the farms ear get into the water bodies through the surface turn off or by deliberate dumping by human being leading to water contamination.

4. Oil spills from the leaking oil containers or pipes. This happened in the Indian Ocean where there are some oil spills from TIPPER in Dar es Salaam in 1990s oil forms a uniform over on the surface of water.

5. Fishing activities, some fishermen tend to use harmful chemicals in fishing which lead to water pollution.

6. Breaking of rocks along the coastal areas or near other sources of water using explosives like dynamite which in turns leads to the dying of marine organisms including fish.

7. Introduction of dust into the water sources mainly due to wind action. This is also another way into which water can be polluted.

Effects of Water Pollution

1. Water pollution can lead to the death of plants and animals if the pollutants and poisonous or causes the rise of temperature to extreme levels.

2. Spread of disease like cholera, diarrhea, dysentery and typhoid.

3. Oil spills kills aquatic organisms because it prevents oxygen from penetrating into water, organisms die because of lacking oxygen.

4. Water pollution leads to the emission of soil smells that causes discomfort to the people round the water body. The soil smell is caused by decomposition of the organic matter introduced into the water body.

5. Decline of tourist activities due to the fact that tourist who depends on water bodies for swimming will find difficult due to the fact that water bodies has been polluted (i.e. presence of toxic chemicals)

6. The color of water changes. The water becomes under due to the presence of impurities.

7. Multiplication of sea weeds as a result of the increase in nutritious from the wastes in water.

8. The death of fish leads to the loss of valuable sources of protein to human being.

Water Pollution

Measures towards Water Pollution Control

1. Encourage the proper use of fishing methods rather than using chemicals, since chemicals end up killing different fish, animal and plant species.

2. The oil container and pipes should be kept properly and frequently inspected so as to avoid the problem of soil spiller

3. Population controlling the population number of people will reduce the amount of water produced.

4. Reduction in the uses of fertilizers and chemicals in agriculture organic agriculture should be encouraged in which manure is used

5. The government and the NGO’S should cooperate in educating people on how to use water, conserve it and where possible they should assist financial in trying to prevent the problem of water pollution.

6. Water should be kept in a clean containers or reservoirs and be covered flighty to avoid contamination

7. Breaking of rocks using dynamite should be discouraged and hence alternative ways should be applied.

8. Dumping of wastes on the land should be hand in hand with land filling method since random throwing of it leads to water pollution

9. There should be recycling of wastes rather than throwing them into the water bodies.

D) NOISE POLLUTION

This refers to the disorganized sound produced from different activities.

Noise Pollution

Causes of Noise Pollution
1. Motor vehicles
2. Construction activities
3. Bombing activities iv. Machines in factories

Effects of Air Pollution
1. Mental and physical illness
2. High blood Pressure problem
3. Death on organism

Effects of Environmental Pollution

1. Wastes dumped carelessly can endanger the health of man as well as other organisms

Empty cans, glass and plastic containers are potential breeding grounds for mosquitoes which spread malaria and other diseases. Rotten organic matter may harbour many disease germs and they also produce noxious smell when they rot. The rotten wastes also attract flies which transmit a number of enteric diseases like dysentery, cholera, and diarrhoea. 

Contaminated water is a source of waterborne diseases such as typhoid, diarrhoea, dysentery, cholera, bilharzia and many other diseases caused by bacteria, parasites and viruses. Contaminated water also spread intestinal parasites such as hook warm, round worms, and ascaris. Exposure to air pollutants can cause serious health problems. Long-term health effects of air pollution include chronic respiratory diseases, lung cancer, heart diseases, and even damage to the brain, nerves, liver or kidneys.

2. Land pollution causes chemical contamination and loss of ecosystem. 

This occurs when the chemicals in the waste matter poison the soil. The plants growing on the poisoned soil, animals that eat these plants and even humans are all affected by these chemical contaminants. This process is called biomagnification and is a serious threat to the ecology. It can lead to the loss of some types of plants and animal life as well as create long-term health problems such as cancer in humans and other deformities. Radiation from nuclear wastes causes healthy problems such as cancers and other deformities.

3. Deforestation causes imbalance in the rain cycle. 

A disturbed rain cycle affects a lot of factors such as reduction in the green cover. Plants help absorb excess carbon dioxide from the air and release oxygen to the atmosphere. This process helps to balance the atmosphere. Without vegetation cover, excessive accumulation of carbon dioxide in the atmosphere causes concerns like global warming, the greenhouse effect, irregular rainfall and floods, among other imbalances.

4. Terrestrial pollution is a big problem in urban areas 

This is where waste production outweighs waste disposal. In such areas you find poor and blocked sewage system, effluent from domestic toilets flowing on the streets and roads, and dirty water carelessly poured on the ground. This makes life in urban areas uncomfortable and a mere nuisance.

5. Chemicals discharged into water bodies have direct toxic effects on aquatic life. 

These chemicals include pesticides, oil spills, mercury, and industrial chemicals. They can kill fish for many kilometres downstream.Discharging the hot water from a power plant into a river could affect aquatic organisms greatly. Even a small increase in temperature can kill organisms from thermal shock. Also the extra heat may disrupt spawning or kill young fish.A high temperature warms the water and lowers the amount of oxygen that can dissolve in that water. This causes the aquatic organisms to increase their respiration rates. All this increases the aquatic organisms’ susceptibility to disease, parasites and the effects of toxic chemicals.Global warming also causes extra heat to the oceans, leading to similar effects explained above.

6. Noise pollution disturbs both man and other animals. 

It leads to problems such as noise-induced hearing loss, headaches and fatigue due to disturbed sleep patterns, hypertension and cardiovascular disease such as myocardial infarction and increases stress leading to psychological disturbance. The effect on animals that are sensitive to sounds beyond the capacity of human years is also noted. This is expressed in terms of fear, increased aggression and changes in normal physiological or bodily functions such as hunger, urination, defecation, pacing, etc.Noise pollution from various ship engines and sonar systems make it difficult for marine organisms like whales, dolphins, and porpoises to communicate, find food and avoid hazards. Excessive noise pollution may cause damage to marine animals’ sound-sensitive organs. This can cause internal bleeding and even death.

7. One of the effects of air pollution is global warming. 

Greenhouse gases in the atmosphere allow ultraviolet radiations to pass through them and reach the Earth. As the Earth’s surface gets heated up, some of the heat is radiated back to the atmosphere. A layer of the greenhouse gases in the atmosphere, acting as a blanket, prevents the heat from escaping to the upper atmosphere. This causes excess heat in the air around the Earth (atmosphere), a phenomenon called global warming.

8. Depletion of the ozone layer

Air pollution causes depletion of the ozone layer. The ozone plays an important role in absorbing dangerous ultraviolet radiation emitted by the sun. These radiations are dangerous as they cause diseases like cancer in organisms, including man.

9. Production of harmful gases

Human activities explained previously produce harmful gases such as oxides of nitrogen and sulphur which are released into the atmosphere. These gases are responsible for the formation of acid rain. Acid rain damages plants and corrodes many ancient buildings, monuments and sculptures made of marble. It greatly affects the aquatic life due to the acidification of lakes and streams.

10. Reducing Visibility

Air pollution by smoke causes smog which reduces visibility, making activities such as driving, surveying and flying difficult. However, this problem mostly affects heavily industrialized countries because of excessive production of gases from industries and automobiles.

LOSS OF BIODIVERSITY

Biodiversity or biological diversity is a term that describes the variety of living things on Earth. Biodiversity also refers to the number, or abundance of different species living within a particular region. It represents the wealth of biological resources available to us.

Loss of biodiversity or biodiversity loss is the ongoing reduction or extinction (entire loss) of species worldwide, and also the local reduction or loss of species in a certain habitat or ecological niche or biome. It also refers to the disappearance of different plants and animal species in a particular geographical unit or community.

Death of Animals

Causes of Loss of Biodiversity

The Earth’s biodiversity is in grave danger. The causes of loss of biodiversity can be either natural or human causes. These causes are summarized in the following main points:

a) Natural Causes

These occur without human intervention. They are mainly caused by natural forces such as Earthquakes, landslides, lightning, and volcanic eruptions. Some of the natural causes of loss of biodiversity include the following:
1. Floods which kill many organisms (plants and animals) where they occur.
2. Lightning in which organisms die due to natural electricity.
3. Wind storms, where strong winds uproot and break plants, and cause massive death of organisms.
4. Pests and diseases occurring at exceptionally high rates tend to kill large numbers of organisms.
5. Landslides and other types of mass wasting, vulcanicity, glaciation and Earthquakes tend to kill organisms in large numbers whenever they occur.

Other ecological factors that may also contribute to the extinction of plant and animal diversity are as follows:
1. Distribution range: The smaller the range of distribution, the greater the threat of extinction.
2. Degree of specialization: The more specialized an organism is, the more vulnerable it is to extinction.
3. Position of the organism in the food chain: The higher the organism in food chain, the more susceptible it becomes.
4. Reproductive rate: Large organisms tend to produce fewer offspring at wide time intervals, e.g. elephants. Elephants are at a greater threat of extinction compared to prolific animals with high reproductive rates like rats.

Death of Plants
b) Human Causes

The main cause of the loss of biodiversity can be attributed to the influence of human beings on the world’s ecosystem. In fact, human beings have deeply altered the environment, and have modified the territory, exploiting the species directly, for example by fishing and hunting, changing the biogeochemical cycles and transferring species from one area to another of the planet. Often, the terms threatened, endangered or rare are used to describe the status of many species. Human activities which lead to loss of biodiversity include the following:

1. Destruction of habitats
The natural habitat may be destroyed by man for his settlement, agriculture, mining, industries, highway construction, dam building, etc. As a consequence, the species must adapt to the changes in the environment, move elsewhere or may succumb to predation, starvation or disease and eventually die.

3. Introduction of exotic species
Species originating from a particular area, introduced into new natural environments can lead to different forms of imbalance in the ecological equilibrium. The introduction of new species increases competition amongst locals and often leads to extinction of native populations. In much of the world, this is happening on farms, too, where foreign breeds of cattle are being imported, pushing out natives.

This means that the world's livestock population is becoming increasingly narrow; and more vulnerable to disease, drought, and changes in climate. The ultimate result of the narrowing of livestock population is the loss of biodiversity and extinction of species.

4. Pollution
Human activities influence the natural environment producing negative (direct or indirect) effects that alter the flow of energy, the chemical and physical constitution of the environment and abundance of the species.

5. Overexploitation of resources
When the activities connected with capturing and harvesting (hunting, fishing, farming) a renewable natural resource in a particular area is excessively intense, the resource itself may become exhausted, as for example, is the case of sardines, herrings, cod, tuna and many other species that man captures without leaving enough time for the organisms to reproduce.

Wild animals are hunted for the commercial utilization of their products such as hides and skins, tusks, furs, meat, pharmaceuticals, cosmetics, perfumes and decoration purposes. In Africa, in recent years 95% of the black rhino population have been exterminated in Africa by poachers for their horn.

6. Climate change
As climate change alters temperature and weather patterns, it will also have an impact on plant and animal life. Both the number and range of species, which define biodiversity, are expected to decline greatly as temperatures continue to rise.

7. Habitat fragmentation
Habitat fragmentation may be defined as an unnatural detaching or separation of expansive tracts of habitats into spatially segregated fragments that are too limited to maintain their different species for an infinite future.

8. Control of pests and predators
Predator and pest control measures, generally kill predators that are a component of balanced ecosystem and may also indiscriminately kill non-target species.

Deforestation

Extent of loss of diversity
A great number of human activities are affecting the environment negatively leading to pollution and climate change. It has been observed that some species have already become extinct and a large number is threatened with extinction. This has lead to increased concern for environmental protection and conservation.

Effects of Loss of Biodiversity

The loss of biodiversity has many effects to humans. Some of these effects are explained below:

1. Reduced food security

Loss of biodiversity leads to the loss of the green economics. It occurs when the plants and other organisms of similar properties to plants are lost. This, in turn, leads to failure of organisms to make carbohydrates, proteins and lipids that are needed for the survival of all organisms on Earth.

Likewise, loss of biodiversity leads to extreme weather events, a situation which is hazardous to all organisms still existing on Earth. This leads to failure of agriculture that is essential in sustaining life.

2. Environmental degradation

Environmental degradation makes the biosphere to be hostile to organisms. Pollution of water, land and air make these environments uninhabitable or nearly uninhabitable to organisms. Vegetation loss through human activities leads to desertification and its consequent negative effects. This further leads to loss of land for agriculture and settlements.

3. Loss of habitats

Destruction of vegetation, artificially by man or naturally by other natural forces, leads to destruction of not only plants per se but also the habitats of many organisms living in there. Thus, organisms are deprived of their natural habitats and forced either to adapt to new conditions or become more exposed to predators.

4. Effect on human health

Human health ultimately depends upon ecosystem products and services (such as availability of fresh water, food and fuel sources) which are necessary for good human health and productive livelihoods. Biodiversity loss can have significant direct human health impacts if ecosystem services are no longer adequate to meet social needs. Indirectly, changes in ecosystem services affect livelihoods, income, local migration, and may even cause political conflict.

Significant medical and pharmacological discoveries are made through greater understanding of the Earth's biodiversity. Loss in biodiversity may limit discovery of potential treatments for many diseases and health problems.

5. Increased contact with disease

The loss of biodiversity has two significant impacts on human health and the spread of disease. First, it increases the number of disease-carrying animals in local populations. Research has shown that the species best adapted to survive critically in fragmented habitats are also the most prolific carriers of pathogens. As habitats are broken apart and reduced in size, these animals become more common, winning out over the species that do not typically transmit the disease.

Secondly, habitat fragmentation brings humans in closer and more frequent contact with these disease-carrying species.

6. Depreciation of aesthetic value

Loss of biodiversity leads to depreciation in aesthetic value of the environment. People are deprived of the happiness they get from the environment. The enjoyment they get by looking at beautiful vegetation, natural landscapes and wild animals is all lost.

7. More unpredictable weather

The loss of species, even those replaced by invasives, has been shown to cause more unpredictable weather.

Killing of Elephants

DESERTIFICATION

Desertification; is the process in which the fertile land is demanded and degraded to produce or initiate desert. Or, Desertification is a type of land degradation in which a relatively dry area of land becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. Or, to put it another way, desertification is the process by which previously biologically productive land is transformed into wasteland. It is the sum of all environmental processes which result in the formation of a desert.

Desertification

Causes of Desertification

Climatic variations and human activities can be regarded as the twobroad causes of desertification. The major causes of desertification include the following:

1. Overgrazing

In arid regions, grass and other vegetation is necessary to keep the soil in place. If the vegetation is overgrazed by livestock, there is very little or no vegetation that remains to prevent the soil from being carried away by wind, water or any erosion agent. If this process occurs long enough, it can lead to desertification.

2. Deforestation

Forests are being cut down at a much larger scale than ever before to be used as fuel, to provide products we use in our daily life, or to simply create more space for agriculture to sustain the growing human population. Once the trees and other vegetation in an area are gone, there is nothing left to hold the soil in place. The soil then turns to dust and can be blown and washed away. In this way, the soil is degraded and the precious soil nutrients are lost, leaving the soil infertile and useless.

4. Outdated and unsustainable agriculture techniques

Improper irrigation methods in arid areas, such as canal irrigation, lead to a build-up of salt in the soil and make it difficult for crops and other plants to grow, hence increasing desertification. Similarly harmful is the cultivation of already deteriorated soils. Besides, while preparing the soil for sowing, natural vegetation that holds the soil in place is removed, making the land more vulnerable to degradation.

Monoculture is one of unsustainable agriculture techniques that leads to soil erosion and ultimately desertification of the land. Monoculture makes the soil very much exhausted. The soil structure, organic matter and fertility are all curtailed. Consequently, soil erosion sets on, which culminates to desertification. In fact, any factor leading to soil erosion is also a causative factor for desertification.

5. Overpopulation

Our planet’s ecosystems sustain life only when balanced. Ecosystems can cope with incremental challenges and adapt but beyond a certain point they collapse. A rapid increase in human population demands higher amounts of natural resources and expands more and more over the landscape, leading to increased desertification.

6. Climate change

As humans continue to remove vegetation from landscapes, there is less vegetation remaining to add moisture to the soil that will evaporate into the air and form clouds that lead to rainfall. With significantly reduced rainfall, drought occurs and leads to a hotter and drier climate, and later causes desertification in the surrounding landscape.

7. Famine, poverty and political instability

While desertification certainly leads to these problems, they can also be a cause of desertification. This is because people on the brink of famine, extreme poverty or political instability in their country need to solve the crisis at the moment and do not think about sustainable cultivation strategies. Unfortunately, the outcome are poor land use practices such as keeping too many animals in a small pen and unsustainable short-term food production, which might destroy soils beyond repair, and put lives of people even more in danger.

8. Natural drought cycles

Natural drought cycles have been responsible for the advance of the desert. Drought leads to loss of soil moisture and hence death of different plant species.

Extent of Desertification

Worldwide, dry lands occupy approximately 40–41% of Earth’s land area and are home to more than 2 billion people. It has been estimated that some 10–20% of dry lands are already degraded and the total area affected by desertification is between 6 and 12 million square kilometres. About 1–6% of the inhabitants of dry lands live in desertificated areas and a billion people are under threat from further desertification.

In Tanzania, the symptoms of desert encroachment are found almost everywhere in the country, although they are much more pronounced in the semi-dry and dry central, western and northern regions of Dodoma, Singida, Tabora, Kigoma, Arusha, Mara, Shinyanga and Mwanza.

These regions experience unusually long periods of drought, extensive deforestation, over-grazing, overstocking, below average rainfall of 600 to 900 millimetres, acute water shortage, and poor harvests that give rise to acute forms of malnutrition, especially among children and the aged.

Tanzania's National Environmental Management Council (NEMC) has repeatedly warned that desertification would cause an extremely negative socio-economic impact and grave ecological consequences, if immediate measures are not taken to check land degradation. Losing an average of 400,000 hectares of land annually through deforestation, Tanzania has failed to protect and conserve its environment and achieve sustainable development.

The problem is made worse by the rising cost of kerosene and cooking gas which is used by many rural and poor people for cooking, heating and lighting. As many people cannot afford kerosene, they have resorted to cutting down trees for fuel (charcoal or firewood) which is relatively cheaper. The Sahel belt, a semi-desert region bordering the Sahara Desert, is expanding southwards.

As the rainfall is becoming less and unpredictable in many areas, the effects of climate change are becoming more glaring and desertification seems to be increasing.



Impacts (Effects) of Desertification

Desertification has many consequences to humans as well as the environment. Its impacts include the following:

1. Decline in agriculture and soil fertility

It leads to decline in agriculture. This is because of drought condition that causes water problems when there is poor precipitation plant growth is inhabited leading to poor food production. Also, as desertification occurs, the soil can be blown or washed away, and valuable soil nutrients are lost. Through the use of unsustainable irrigation techniques, salt can also build up in the soil, rendering the soil useless for growing crops or other plants.
As the soil dries out, it hardens and it becomes difficult for water to penetrate below the soil’s surface. And what is left is a lifeless pile of dust instead of a life-giving medium. Desertification reduces soil fertility, particularly base cation content, organic matter content, pore space, and water-retention capacity of the soil.

2. Loss of species or biodiversity

It leads to the loss of important species of trees and animals as well as organism like bacteria. Desertification reduces the ability of land to support plant life. Loose soil buries plants, or their roots become exposed and cannot fulfil their function. With plants dying, rainwater gets washed away instead of being drawn into the soil, which only scales up the problem as remaining plants do not have enough moisture to survive dry spells as they used to.

Likewise, the species that once lived in a fertile and productive land may not survive in a newly desertified region. With a changing ecosystem, species must adapt to their new climate or migrate to a more favourable climate. Unfortunately, some of them also become extinct for their inability to cope with a sudden change of their environment.

3. Soil erosion

The desert advance acceleration of soil erosion which leads to deforestation and loss of arable land. Erosion also affects different structure like building bridge, roads and railway line. The reduction in plant cover increases soil erosion due to increased runoff and direct exposure to wind. Also, This can result in the decrease of water storing capacity of soils. The process of desertification is worsened as the soil becomes increasingly arid, and there are no more plants to hold it in place and distribute nutrients. Soil erosion is the final step that closes the loop of continual soil deterioration that is impossible to revert.

4. Disasters

Desertification makes natural disasters worse. Events such as flooding, dust storms, and pollution, all become stronger in areas with heavily degraded soils. Without any plants stabilizing the soil and slowing down the runoff, rainwater easily accumulates and floods human settlements. Apart from causing damage, flood water also picks up unwanted pollutants while making its progress through urban areas, and that’s how pollution spreads over vast areas.

5. Famine, poverty, and starvation

Desertification reduces vegetative productivity, leading to long-term declines in crop and livestock yields, plant standing biomass, and plant biodiversity. These changes reduce the ability of the land to support people, often sparking an exodus of rural people to urban areas. Due to drought conditions and a loss of productive land, local people find themselves experiencing famine and poverty, as well as the starvation of themselves and their livestock.

6. Economic loss

Desertification forces the government to use its financial resources to rehabilitate and maintain the degraded land. This leads to economic loss as the money that could otherwise be spent on social services is directed towards rehabilitation of degraded land.

7. Migration of people

Migration of people from affected area to productive land area. People and other animals are compelled to move from areas with scarcity of water to areas that experience enough rainfall.

8. Pollution of water sources

Vegetation plays an important role in cleaning our water. Plants function like natural filters, storing pollutants such as heavy metals from water in their own bodies. Barren soils lack this green filter, and therefore, more of these harmful substances enter our groundwater reservoirs.

9. Decline in tourism

The desert also contribute at high rate the destruction of wild life animals and species which in turn leads to decline of tourist industries in the country .This happens when animal die or migrate away or when lakes and rivers dry up.

10. Scarcity of water makes travel long distance in search for water for domestic uses like cooking, drinking, washing.

The above list of causes and effects of desertification is just a brief fraction of the whole scope of such an extensive problem taking place on our lands every day. Majority of those who are affected the most by this problem are as usual the world’s poorest nations, where people struggle daily with the direct impacts of climate turning against them, and deserts claim more of their already scarce soils. Therefore, it is important to realize how valuable soil conservation is and try to help protect our natural resources.

Death of Animals

Measures to be Taken in order to Minimize the Rate of Desertification

1. Alternative source of energy should be used in the developing countries especially in natural areas where the majority live. Alternative energy includes solar energy, wind power, bio gas and hydroelectric power.

2. The local people should be educated on how to conserve vegetation. Some programs like afforestation and reforestation should be encouraged in order to mitigate them.

3. The government should advice some substantive policies whose objectives are to lay down principles to guide development and control of forests.

4. The government should encourage forest conservation by avoiding deforestation.

LAND DEGRADATION

Land degradation refers to the deterioration of the quality of land (soil) through the loss of fertility, soil pollution erosion and mass wasting.

LOSS OF SOIL FERTILITY

This refers to the decline in the soil ability to support plant growth due to the lack of plant nutrients necessary for growth.

Land Degradation and  Soil Infertility

Causes of Soil Infertility

1. Leaching process: This process contributes to the soil infertility due to the fact that nutrients which are necessary for plants growth and washed away.

2. Over cultivation: In a certain area caused by the rapid population growth. The crops grown on the some pieces of land for a long time lead to depletion of nutrients.

3. Monoculture: That involves cultivation of one type of crop without crop of inter cropping. Nutrients are used up without replacement and the soil structure can be destroyed rendering the soil unstable.

4. Soil erosion: Which accelerated by poor land management like deforestation feat cultivation on the slopes etc.

5. Mass wasting: That leads to the loss of the upper layer of soil and its nutrients

6. Severe loss of soil water through excessive evaporation especially in arid and semi-arid.

Land Degradation and  Soil Infertility

SOIL MANAGEMENT AND CONSERVATION

Soil management Refer to the skillful uses or wise utilization and control of quality of soil (land resources) Soil conservation Refers to the process of preserving soil for proper and sustainable use.

Measures of Soil Management and Conservation

1. Educating people so as to promote and encouraged land management skills among them this has to be undertaken by the government collaboration with NGO’S and some individual.

2. Training and encouraging farmers to uses proper farming methods like crop rotation counters roughing and inter cropping Planting of cover crops forestation and reforestation in order to check soil erosion.

3. Reducing or stopping the uses of industrial chemical which tend to accumulate in the soil and causes soil pollution.

4. Waste products should be recycled rather than dumping them in the soil.

5. Destocking animal members should be reduced or controlled so as to avoid overgrazing that leads to destruction grass.

6. Encouraging dry farming that involves mulching in order to reduce loss of water through evaporation

7. Land filling with bush wood should be used where the soil has been severely eroded producing gullies.

8. Population should be controlled so as to discourage excessive exploitation of resources which in nature leads to land degradation

9. Alternative energy resources should be exposed and used effectively to avoid the excessive exploitation of forest and oil which causes hazard to the environment.

10. Radioactive materials should be dumped very deeply in the soil to prevent the upper soil layer from being high affected.

11. Terracing and contraction of some stone lines should be undertaken so as to control the movement of water and forces it to get into the soil rather than flowing over the land.

ACIDIC RAIN

Acidic Rain results from solution of gases like carbon dioxide that react with water to form acids. Therefore acidic rain is rain containing more acids than the normal amount. Acidic rain It is formed in the air from Sulphur dioxide and nitrogen oxide which are emitted by thermal power stations, Industries, Motor vehicles, burning of coals and also industrialisation.

Acidic Rain

Effects of Acidic Rain

1. It led to the increase of acidity in water bodies hence killing of aquatic animals and plants

2. Reduction of the rate of soil fertility due to the increase amount of acidity into the soil.

3. Increase the rate of leaching process.

4. Destruction of different structure like buildings, bridges, railways as result of the corrosive action of acid on paint and rocks containing calcium.

5. Sulphur acid lead itching and irritation of eyes in human beings and animal

6. Erosion of limestone rock lead to the formation of features like sink holes dollies and garpikes

Acidic Rain

Measurements to Combat the Problem of Acidic Rainfall

1. Spraying the trees to wash off the acids and adding of time to the soil lakes and rivers to reduce acidity . The good example is Germany, UK and Scandinavia, countries where this process has been used advice.

2. Reduction of emission of Sulphur dioxide and nitrogen oxide by using non fossil fuel, coal which contains less Sulphur, removing Sulphur from coal.

3. Introducing new boilers in power station which can burn Sulphur dioxide into ash.

4. Trapping Sulphur dioxide from the waster gases and spraying it with water so that it can form sulphuric acid which can later be neutralized by adding line.

5. Using alternative sources of energy which do not pollute the air the country can turn the coal fired power station into gas fired power.

6. Recycle the waste to avoid unnecessary champion action that lead to the production of Sulphur gas

7. Strict policies should be formulated to restrict the case of energy that leads to emission of Sulphur dioxide.

FLOODS

Refers the period of high river discharge or over flow of water along the coast due to extremely high tides and storm waves


Flood

Causes of Floods

1. Flood occur due to the collapse of reservoirs like dam, emergence of spring, melting of ice and breaking of the water pipes

2. Also flood can occur due to the heavy rainfall that take place in a particular place and they affect so much the law land area especially where vegetation been cleared. They occur most frequently in the humidly region like equatorial areas.

Factors that can Accelerate Flooding in Law Land Areas

1. Shallowness of the soil due to the presence of the impermeable rock layer just near the surface.

2. Earth quakes that take place below the sea tends to lead to the formation of large waves – flooding

3. Damming of the river by human being by lava spread out during volcanic eruption.
4. Blocked up drainage system in town and cites can lead to the flooding

5. Shallowness and name lines of the river system can also lead to flooding

6. Cleaning of vegetation accelerate flooding because on a base surface water runs freely to the stream

7. It can also take place where the rives has many bends



Impacts of Flood

1. Death of people and animals for example the frequent flood in Bangladesh has claimed the death of many people leading to depopulation.

2. Destruction of farm land they can be destroyed by running water leaching to devastation of crops.

3. Outbreak and spread of disease especially water born disease which then affected the health of people and sometimes death.

4. Floods also lead to the demolition of houses rending people homeless.

5. Silting of dams and other water resources resulting in the problem of water conservation and inadequate water supply.

6. Flood can lead to soil and air pollution
7. Occurrence of the soil erosion and the occurrence of lands.

8. Destruction of infrastructure like railways, roads and bridges.
9. Floods bring problem of industrial location in a particular place,.

10. It leads to migration of people who move as refugees

11. Destruction of various economic sectors like farms and industrial structures this lead to occurrence of poverty in the country.

12. Destruction of transport system hinders the movement of goods and services from one place to another.


Migration of People

Response to the Occurrence of Flood

1. There should be proper management of the watershed catchment areas through planting trees people should be allowed to settle in the catchment areas

2. Construction of dams across the river channels helps in combating the problem of flood which affects the low land areas.

3. The stream of the rivers should be deeper widened and straightened so as to increase the speed of the river down the slope to the sea.

4. People should be frequent inspection and cleaning of the drainage by flooding.
5. There should be frequent inspection and cleaning of the drainage system.

6. Availability of rescue team which is skilled and actives in rescuing people affected by floods

7. International cooperation should be intensified so as to improve the techniques of combating this environmental problem.

DROUGHT

Is a state on an area facing prolonged condition of dry without precipitation or a long period of dry weather. Drought and desertification have something in common in terms of occurrence and affects.

Drought

Causes of Drought

a) Natural Cause

1. Wind system dynamics. Wind system that are dry since have blow across very narrow water mass stretch cause drought as they have not picked enough moisture for rain formation; Example Harmaton wind of West Africa has contributed to the occurrence of drought condition particularly in the Sahara region.

2. Shifting position of the overhead sun. As a shifting of over head sun takes place then rainfall regime shift. It shift in the northern hemisphere there occur dryness in the southern hemisphere

3. Location of some place: Some place is located in the wind side of the mountains and therefore experience dryness. Good example is Namib desert

4. Natural fires: There is the fire caused by natural hazard like lighting of and volcanic eruption.

5. Rain shadow effect produced by high mountain ranges

Death of Crops

b) Man Induced Cause

These are activities carried all by man
1. Lumbering that leads to deforestation due to excessive cutting of trees

2. Bad agriculture practices like overgrazing, over cultivation and shifting cultivation.
3. Establishment of new settlement areas due to the increase in population lead to cutting of trees.

4. Mining activities and construction of dams can also cause deforestation.
5. Industrial activities and crops have an impact on the occurrence of drought

6. Low level of technology and poverty there has led to occurrence of drought.
7. Casual burning of natural fire due to eruption of volcanoes.



Impact of Drought

1. Drought has led to poor supply of water for domestic uses, agricultural uses and industrial activities.

2. Disappearance of vegetation and animal species

3. Poor supply of energy and power to some people who depends on fire wood as the man source of energy

4. Drying of water bodies due to excessive evaporation
5. It has facilitated desertification process Migration of people from one area to another

6. Decline of industries especially food processing industries that depend on agricultural production

7. Women harassment due to the fact that women are forced to move long distance in search for fire wood.


Death of Animals

Measuring to Combat the Problems of Drought

1. Embarking an forestation programmers the trees moisture to the atmosphere and hence led to rain formation

2. The uses of proper farming method which do not deplete vegetation Control of population should be encouraged so as to avoid the excessive exploitation of vegetation

3. The water conservation centers should be established like dams so as to promote irrigation streams

4. Farmers should be given proper education on how to conserve water resources sustainability to avoid environmental degradation

5. Strict policies should be instituted so as to restrict excessive use of trees

6. There should be the alternative energy sources like solar energy, wind energy, and Geothermal.

GLOBAL CLIMATIC CHANGE

The world climate changes “Refers to all form of climatic inconsistently but because the climate is never static the terms is more properly described as a significant long term abnormal fluctuations in terms of precipitation wind system and all other aspects of the earth’s climate. For quite long period of time the world has been experiencing global climatic changes including extreme cooling or extreme warming of the atmosphere.

Or, Global climate change is the alteration in the characteristics and pattern of the world climates that is attributed to human activities which alter the composition of the global atmosphere. It should be noted that, to some extent, nature too can cause climate change, only that its rate is very slow compared to that associated with human activities.



Causes and Consequences of Global Climate Change

Energy from the sun drives the processes of heat and moisture transfer in the atmosphere. Any processes or activities that interfere with sun, and hence the solar energy, affects the climate of the Earth. Such interferences can be natural or man-caused. These factors, therefore, are considered to be the causes of global climate change.

a) NATURAL CAUSES

The natural causes of global climate change include the following:

1. Variation in solar radiation

The energy emitted by the sun only varies slightly. This change in solar radiation is related to the number of sunspots. Sunspots are darker areas on the sun’s surface. A sunspot develops where an intense magnetic field weakens the flow of gases that transport heat energy from the sun’s interior. Sunspots appear dark because their temperature is lower than the surrounding area.

Approximately every 11 years, the number of sunspots changes from a maximum number to a minimum number. The sun emits slightly more radiation during active periods of sunspots. While many sunspots may contribute to warmer global climate, fewer sunspots appear to be associated with a cooler global climate.

It is estimated that solar output could decrease at a rate of 1% per century. This alone could lead to a global drop in temperature of up to 1°C.

2. Volcanic eruptions

Volcanic eruptions discharge carbon dioxide, but they may also emit aerosols, such as volcanic ash or dust, and sulphur dioxide. Aerosols are liquids and solids that float around in the air. They may also include soot, dust, salt crystals, bacteria, and viruses. Aerosols float in the atmosphere for long periods of time and are transported by wind around the planet. The aerosols scatter incoming solar radiation, causing a slight cooling effect.

This was the case in 1816 when Indonesia’s Mount Tambora erupted violently. A similar situation occurred when Mount Pinatubo (in Philippines) erupted in 1991 causing a significant dip in global temperatures in the following year or two.

3. Variation in atmospheric carbon dioxide

The level of carbon dioxide concentration in the atmosphere dictates the global temperatures. The higher the concentration, the warmer is the temperatures. An increase in the population of organisms, including man and other animals, causes an increase in atmospheric carbon dioxide and hence global warming. If temperatures were to drop to freezing point, a large volume of carbon dioxide would be trapped in the frozen water releasing less quantity in the atmosphere. This would lead to cooler conditions.

4. Movement of crustal (tectonic) plates

As tectonic plates move over geological timescales, landmasses are carried along to different positions and latitudes. These changes affect global circulation patterns of air and ocean water and the climate of the continents. Studies show that, since the industrial revolution, the Northern Hemisphere has warmed more than the Southern Hemisphere. This is because the Northern Hemisphere has a larger percentage of Earth’s landmass compared to ocean than the Southern Hemisphere.



b) HUMAN CAUSES

Humans are increasingly influencing the climate and the Earth's temperature by Burning fossil fuels, cutting down rainforests and keeping livestock. This adds enormous amounts of greenhouse gases to those naturally occurring in the atmosphere, increasing the greenhouse effect and global warming.

The greenhouse effect causes the atmosphere to retain heat. When sunlight reaches the Earth’s surface, it can either be reflected back into space or absorbed by Earth. Once absorbed, the planet releases some of the energy back into the atmosphere as heat (also called infrared radiation). Greenhouse gases like water vapour (H2O), carbon dioxide (CO2), and methane (CH4) absorb energy, slowing or preventing the loss of heat to space. In this way, greenhouse gases act like a blanket, making the Earth warmer than it would otherwise be. This process is commonly known as the “greenhouse effect.”

Increase in atmospheric gases comes from human activities through emissions from burning coal, gas and oil in power plants and cars; cutting down and burning forests; tiny pollution particles (aerosols); black carbon pollution more commonly referred to as soot; and changes in land use. Forest and grassland fires and burning of litter, including plastics, also contribute to more gases in the atmosphere.

Deforestation reduces the population of plants which are the main consumers of carbon dioxide, hence leading to accumulation of excess of the gas in the atmosphere. Industrial and agricultural activities are also responsible for contributing gases such as methane, nitrous oxide, chlorine, fluorine and bromine to the atmosphere. Massive quantities of garbage also give off considerable quantities of these gases, especially methane.

Industrial chemicals called chlorofluorocarbons are used in aerosols, refrigeration, plastic industries and electronics. These are carelessly released into the atmosphere, thus causing damage to the protective ozone layer.

Production of Green House Gases

GLOBAL WARMING AND GREEN HOUSES PHENOMENA

Global warming: This is the unusual increase in temperature of the earth’s atmosphere which is caused by the green houses effect.

Greenhouse effect: Refers to the situation in which the atmosphere traps and retains heat energy from the sun in the lower level leading to the rise in temperature.  Greenhouse gases include water vapour (H2O), carbon dioxide (CO2), methane (CH4) and chlorofluorocarbon (CFCs).

Global Warming

Effects of Global Warming and Green House

1. The rise in temperature has led to the melting of ice in various parts of the world e.g. The cap at the peak of Mt Kilimanjaro has decreased in size due to the effect of global warming

2. The melting of ices has led to the increase of water in the sea and hence the sea level rises. As results of those phenomena some of coastal areas are flooded.

3. Global warming has led to the occurrence of strong storms in different parts of the world that kill people and destroy properties.

4. Some cold areas have become warm such that tropical crops are grown.

5. Disappearance of some animals and plant species due to the failures to adopt the abrupt in temperature.

6. Global warming has caused the occurrence of precipitation in other areas which is used to be dry due to the changes in hydrological cycles.

7. Decline of production due to drought and desertification process which then leads to poverty and death of people 8. Spread of disease like skin cancer, malaria and other.



Mitigating Measures against Global Warming and the Green Houses Effect

1. Discouraging the uses of burning of material that release harmful greenhouse gases such as CO2, CFC's

2. Alternative sources of energy, which are environmentally friendly, should be encouraged e.g. geothermal, power, solar energy, and wind energy.

3. Formation of an international policies and cooperation among different nations in the fight against air pollution.

4. Modification of the combustion system in the machines in order to attain efficient fuel burning and cut off massive release of greenhouse gases especially carbon dioxide.

5. Control of pollution in order to discourage excessive use of fossil and biomass energy.

6. Large scale rice cultivation should be avoided or improved to cut off the release of methane gas.

7. Recycling of wastes should be encouraged rather than burning or dumping on the surface.

8. Encouraging people to walk more than using cars can lead to the reduction of emission of greenhouse gases. Also mass-transit cars should be used more than many small cars.



Consequences of Global Climate (Global Warming) Change on Environment

Global climate change has already had observable effects on the environment. Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have shifted and trees are flowering sooner. Effects that scientists had predicted in the past would result from global climate change are now occurring: loss of sea ice, accelerated sea level rise and longer, more intense heat waves.

Humans and wild animals face new challenges for survival because of climate change. More frequent and intense drought, storms, heat waves, rising sea levels, melting glaciers and warming oceans can directly harm animals, destroy the places they live, and wreak havoc on people’s livelihoods and communities. 

The effects of climate change on the environment include the following:

1. Increased precipitation

Precipitation (rain and snowfall) has increased across the globe, on average. Global warming leads to a rise in temperature and hence increased evaporation. The ultimate outcome is more than average rainfall in some regions, causing flooding and making the wetlands wetter than before.

2. Increased atmospheric temperature

As noted above, the increase in temperature would make some regions hotter than before. This extreme temperature would make some regions turn semi-arid because of increased evaporation. Consequently, water resources could dry up at a faster rate. The Earth's average temperature has increased about 1°C during the 20th century.

Increase in Temperature
                        
3. Rise in sea level

Ice is melting worldwide, especially at the Earth’s poles. This includes mountain glaciers, ice sheets covering West Antarctica and Greenland, and Arctic sea ice. The melting ice and glaciers would cause an increase in sea level.
Likewise, the ice cap on Mount Kilimanjaro and glaciers on Mount Kenya are shrinking because they are melting more than before.

Rise in Sea Level

4. Change in world’s climate patterns

Climate change resulting from increasing temperatures will likely include changes in wind patterns, annual precipitation and seasonal temperatures variations. Climatic patterns in most parts of the world have already changed. Rains fall when least expected and at irregular intervals. This has greatly affected the timing of planting and harvesting activities. Sometimes the rains fall so heavily to cause floods, or too little leading to drought. Most of the arable land that once used to be productive is slowly turning arid. With time, farmers will run short of the land for cultivation, a fact which will result in famine.

5. Ocean acidification

As levels of atmospheric carbon dioxide increase, the oceans absorb some of it. This increases the acidity of seawater. Because acids dissolve calcium carbonate, seawater that's more acidic has a drastic effect on organisms with shells made of calcium carbonate, such as corals, mollusks, shellfish and plankton. The acid water is likely to dissolve the carbonaceous shells, thus endangering the lives of these aquatic creatures. Change in ocean acidity will also affect fish and other aquatic animals and plants.

Ocean Acidification

6. Disruption of natural ecosystems

Change in conditions of a natural ecosystem due to climate change is likely to make some species of organisms extinct while others might adapt to the new conditions or move to suitable environments. For example, some butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas. In general, many species have expanded their ranges poleward in latitude and upward in elevation.

There has been some evidence on changes in distribution of ecosystems, e.g. desert ecosystems have expanded, and tree lines in mountain systems have changed. Desertification could increase due to increased soil erosion. Grasslands might expand while forest areas would shrink. Changes in the composition of ecosystems have also been observed (e.g. increased climbing plants in tropical forest). Such changes may affect ecosystem functions and services.

However, changes in biodiversity and ecosystem services due to climate change are not all negative, with some species either thriving or adapting.

7. More frequent and intense heat waves

Dangerously hot weather is already occurring more frequently than it did 60 years ago, and scientists expect heat waves to become more frequent and severe as global warming intensifies. This increase in heat waves creates serious health risks, and can lead to heat exhaustion, heat stroke, and aggravate existing medical conditions.

8. Loss of habitats and biodiversity

Many species of plants and animals are already moving their range northward or to higher altitudes as a result of warming temperatures. Additionally, migratory birds and insects are now arriving in their summer feeding and nesting grounds several days or weeks earlier than they did in the 20th century. Warmer seasons will lead to an increase in pests and disease-causing pathogens that were once confined to tropical and subtropical areas, killing off plant and animal species that formerly were protected from disease. For example, spruce bark beetles have boomed in Alaska thanks to 20 years of warm summers. The insects have chewed up 4 million acres of spruce trees.

9. Famine and disease threat

Agricultural systems will likely be highly affected. Though growing seasons in some areas will expand, the combined impacts of drought, severe weather, lack of snowmelt, greater number and diversity of pests, lower groundwater tables and a loss of arable land could cause severe crop failures and livestock shortages worldwide. This loss of food security might, in turn, create havoc in international food markets and could spark famines, food riots, political instability and civil unrest worldwide.

The effect of global warming on human health is also expected to be serious. An increase in mosquito-borne diseases like malaria and dengue fever, as well as a rise in cases of chronic conditions like asthma, are already occurring, most likely as a direct result of global warming.

Famine

10. Increased ultraviolet radiation

Increased ultraviolet radiation from the sun above normal rates is caused by depletion of the ozone layer. This radiation is harmful to organisms. Humans, animals and plants are affected in the following ways:
a) Increased sunburn.
b) Snow blindness.
c) Increased eye diseases such as cataracts.
d) Increased incidences of skin cancer, including melanoma (a cancer that develops in melanocytes, the pigment cells present in the skin).
e) Impaired ability of the body’s immune system.
f) Rapid aging and skin wrinkling.
g) Lower crop and timber yields.
h) Lower fish population.


Increased ultraviolet radiation

Waste Mismanagement

Is the poor disposal of wastes on undersigned areas. Examples of wastes are solid (bottles, plastic materials, iron). Liquid (Sewage from latrines, oil). Gaseous

ENVIRONMENTAL CONSERVATION

Environmental Conservation refers to the protecting of environment from being destructed through practicing various ways of environment protection such as destocking, afforestation and planting of cover plants.

Ways of Conserving the Environment include:

1. Destocking, refers to the process of reducing number of animals on the environment because when the number of animals increase on the environment, they can feed on all the plants which help to prevent soil erosion or landslides.

2. Afforestation and Reforestation refer to the process of planting trees in bare land and re planting trees in the presence of other trees.

3. Control industrial gases and industrial sewage system, industrial location should be far apart from the water sources.

4. Practicing proper irrigation skills. When irrigation is practiced improperly especially on the land with slope the water can wear out the nutrients and cause poor production.

5. Control of industrial fertilizers instead of depending on industrial fertilizer we can use manure since manure has no effect on the soil while industrial fertilizers add acid on the soil

6. To control fishing activities, bad fishing method should be discouraged for example charging and punishing for those who practicing bad methods. Control construction of road and buildings to avoid construction of building on steep slopes because this can accelerate soil erosion.

Planting Trees

FAST RATE OF POPULATION AND URBAN GROWTH ON ENVIRONMENT

In the previous chapters on human population and settlements we learned in detail about the extent and causes of rapid population and urban growth. The following is a reminder of the causes of the fast rate of population and urban growth.

Causes of the Fast Rate of Population Growth

The rapid growth of the world’s population over the past one hundred years results from a difference between the rate of birth and the rate of death. The growth in human population around the world affects all people through its impact on the economy and environment. The current rate of population growth is now a significant burden to human well-being. Understanding the factors which affect population growth patterns can help us plan for the future. Causes of overpopulation include the following:

1. Decline in the death rate

The fall in death rates, that is, a decline in mortality rate is one of the fundamental causes of overpopulation. Owing to the advancements in medicine, man has found cures to the previously fatal diseases. The new inventions in medicine have brought in treatments for most of the dreadful diseases. This has resulted in an increase in the life expectancy of individuals. Mortality rate has declined leading to an increase in population.

Owing to modern medications and improved treatments to various illnesses, the overall death rate has gone down. The brighter side of it is that we have been able to fight many diseases and prevent deaths. On the other hand, the medical boon has brought with it, the curse of overpopulation.

2. Rise in the birth rate

Thanks to the new discoveries in nutritional science, we have been able to bring an increase in the fertility rates of human beings. Medicines of today can boost the reproductive rate in human beings. There are medicines and treatments, which can help in conception. Thus, science has led to an increase in birth rate. This is certainly a reason to be proud and happy but advances in medicine have also become a cause of overpopulation.

3. Migration

Immigration is a problem in some parts of the world. If the inhabitants of various countries migrate to a particular part of the world and settle over there, the area is bound to suffer from the ill effects of overpopulation. If the rates of emigration from a certain nation do not match the rates of immigration to that country, overpopulation makes its way. The country becomes overly populated.

4. Lack of education

Illiteracy is another important cause of overpopulation and lack of family planning is commonly seen among the illiterates. Those lacking education fail to understand the need to prevent excessive growth of population. They even don’t know the harmful effects of overpopulation.

They are unaware of the ways to control population. This is one of the major factors leading to overpopulation. Due to ignorance, they do not take family planning measures, thus contributing to a rise in population.

Population and Urban Growth

Causes of the Fast Rate of Urban Growth

Urban areas are growing faster in LEDCs than anywhere else in the world, but this growth brings problems and challenges, all of which require good management and solutions. Although the process of urbanisation happens in both MEDCs and LEDCs, the fastest-growing cities in the world are in LEDCs.

The reasons for the growth of urban areas include the following:
1. A lack of employment opportunities in the countryside is among the driving forces of urban growth. Overpopulation and poor crop yields are all push factors that make people leave the countryside and move to urban areas.
2. Better paid jobs in the cities, an expected higher standard of living, and more reliable food attract people to the city.
3. People who migrate to towns and cities tend to be young and so have higher birth rates in that age range.
4. Better medical conditions compared to the countryside mean more successful births and a better life expectancy.

Effects of Fast Rate of Population and Urban Growth on the Environment

One of the factors responsible for environment degradation is population growth or population density and urban growth. This is because the growing population demands more and more (non-renewable) resources for its own application. The environmental problems associated with the rapid population and urban growth includes the following:

1. Accumulation of waste

Due to overpopulation, the rate of generating waste is higher than it can be removed by the local council, city or municipal authorities. Difficulty in dealing with urban waste leads to environmental pollution. A lot of piles of waste are found scattered here and there in many urban centres among the LEDCs. Such a situation is a potential threat to public health because dirt is the major breeding ground of germs that cause various diseases such dysentery, typhoid, diarrhoea and cholera. The accumulated waste also produces a bad smell which pollutes the air.

2. Deforestation

Fast population growth leads to an increase in demand of land for settlement and agriculture. As a result, more land is cleared to establish agriculture as well as settlements. Further clearing of the vegetation can lead to desertification and climate change. That is why amount and frequency of rainfall in urban areas has shown a great fluctuation in the past few decades.

3. Soil and water pollution

To feed the ever-growing human population, farmers use diverse agrochemicals to produce more food to feed the population. Excessive use of agrochemicals pollutes the soil and destroys soil structure. Soil microorganisms are also killed. As a result, the soil fertility is curtailed a great deal.

As the farmers struggle to produce more food using a limited land resource, some tend to grow crops near water sources. This leads to pollution of water via the eroded soil and agrochemicals. Likewise, due to land scarcity, people live very close to water sources such as rivers, streams and lakes. The closer the settlements are to water sources, the more likely they can pollute the water.

4. Loss of biodiversity

Due to his destructive activities, man has extracted more and more minerals from the Earth. Animals have been hunted and plants have disappeared. There has been a loss of biodiversity which has led to ecological imbalance.

5. Climate change

The gases produced by industries and automobile exhausts accumulate in the air and cause greenhouse effect which contributes to global warming with its adverse effects to the environment and living organisms, including humans.


Deforestation

The Impact of Poverty on Environment

There is a strong relationship between poverty and the environment:

1. Poverty is one of the main causes of forest and woodland degradation in developing countries, especially in Africa, and it is both a consequence and a cause of this degradation. A degraded environment produces less, so people become more vulnerable, for example, to waterborne and other diseases.

2. Poverty leads to deforestation through inappropriate use of wood and other resources for cooking, heating, housing and crafts. This is because people cannot afford cooking gas and kerosene. Some cut down trees to sell firewood or charcoal in order to get income to buy some essentials such as food and clothing. When people lack adequate financial and other resources, they are left with no choice but to turn to unsustainable use of natural forests and woodlands to meet their basic needs. It becomes a vicious circle.

3. Insufficient access to education and information make it difficult for poor people to manage available natural resources in a sustainable and sound manner, thus creating loss of livelihood opportunities and of biological diversity.

4. Air pollution generated by inappropriate production techniques used by poor people out of lack of better knowledge or lack of capital to invest in environmental friendly technologies, is also responsible for global warming and climate change.

5. Poverty often confines poor people in rural areas to marginal lands, thus contributing to an acceleration of erosion, increased ecological vulnerability, landslides, etc. Lack of resources in poor neighbourhoods leads to inadequate waste collection and waste management with subsequent health problems.

6. In rural areas, poverty leads to practising poor farming methods like shifting cultivation, monoculture, overcultivation and overgrazing. Bush fires set by honey collectors are also common. All of these render the soil bare and prone to erosion.

7. Poor people cannot afford to pay for cleaning and other community services. They also live in poor and unplanned settlements. As a result, the most severe environmental health problems are found predominantly in low-income homes and neighbourhoods. These include poor access to water, bad sanitation, contaminated food, uncollected waste, smoky kitchens and a range of insect vectors.

8. Siltation of the urban drainage systemsIn urban areas the poor are engaged in urban agriculture, which has resulted in the destruction of green belts. Stream bank cultivation has contributed to siltation of the urban drainage systems.

9. Urban residents generally consume more renewable resources than rural people, placing heavy demands on the environment. Large concentrations of people also generate huge volumes of waste, resulting in pollution and health problems. Cholera and other water-borne diseases are spread through water often contaminated with untreated human waste and sewage.

10. Many poor women lack the resources necessary to engage in birth control. Therefore, it is common for poor women to continue having children well after they would have liked because of little or no access to resources and education. The more global population grows, the more weight is placed on the environment. Every human being consumes their share of resources from the environment, and with so many births originating from poor communities, the burdens placed on the environment grow heavier and heavier each day.

Bush Fire for Preparing Farms

ENVIRONMENTAL CONSERVATION

Environmental conservation is the protection, preservation, management, or restoration of natural environments and the ecological communities that inhabit them. It entails the protection and preservation of natural resources from destruction, wastage or loss. Thus, conservation of the environment involves the conservation of the natural resources. The natural resources include soil, minerals, water, air, animals and plants.

Various Ways of Conserving the Environment

There are numerous ways in which environmental protection and conservation can be achieved. The following are some of the measures that can be taken to conserve the environment:

1. Recycling and re-use

Emphasis is being put on recycling by buying reusable and biodegradable products as much as possible. Whether it is glass or paper, plastic or metal, all these materials can be re-used. Remember it takes a million years for glass to decompose. Plastic bags are not biodegradable either and they are used in huge quantities every year. Reusable containers and bags would be a healthy, environment-protective alternative. Therefore, re-use every reusable material rather than damping it onto the environment.

2. Afforestation and reforestation

Reforestation refers to establishment of a forest on land that had recent tree cover, whereas afforestation refers to establishment of a forest on a land that has been without a forest for much longer. Trees absorb excess carbon dioxide from the air, thus helping to curb greenhouse effect and global warming. Trees also help in attracting rainfall, controlling soil erosion, and modifying the climate.

3. Rehabilitation of derelict land

People engaged in quarrying and mining are encouraged to rehabilitate the land on which the activities have taken place. The simplest method of reclaiming a derelict land involves simply filling the undulating land with large amounts of heavy rock and/or cement until the desired level is attained. Draining of submerged wetlands is often meant to reclaim land for agricultural use. Deep cement mixing is used typically in situations where the material displaced by either dredging or draining may be contaminated and hence needs to be contained.

Various techniques are employed in land reclamation. The method chosen for reclaiming the land depends on the state of the land in question. The methods often employed include irrigation, afforestation and reforestation, drainage, landfill, flushing or acidification.

4. Reducing the use of agrochemicals

Farmers should be advised and encouraged to avoid dependency on agricultural chemicals (fertilizers, herbicides, pesticides, etc). All of these chemicals poison the soil, and affect animals and crops a great deal. Instead, farmers should use organic manures and chemicals to fertilize their farm fields and to control pests and diseases. Organic manures and pesticides do not pollute the land or affect crops and animals.

5. Setting up organizations and institutions

Many organizations have been set up for the purpose of conserving the environment. These organizations include international organizations, government ministries and agencies and non-government organizations. Examples of government ministries and agencies include the Ministry of Natural Resource and Tourism and the National Environment Management Council (NEMC) respectively. An example of an international agencies concerned with environmental conservation is the United Nations Environment Programme (UNEP).

6. Legislation

The laws that govern environmental conservation are being made and enacted. The laws aim at curbing environmental destruction by punishing or fining those individuals who destroy or litter our environment.

7. Education

People are being educated about the importance of conserving the environment for their benefits and future generations. Environment education is being continually offered in schools, colleges, universities and other organizations. Academic institutions now offer courses such as environmental studies, environmental management, and environmental engineering that teach the history and methods of environmental protection.

8. Research

Research is being carried out on the best ways to protect and conserve the natural resources. Some of the areas of research include the following:
- Alternative sources of energy;- methods of preventing and controlling pollution;
- Sustainable use of natural resources;
- Recycling and reuse of material; and
- Environmental impact assessment

9. International agreement

International organizations such as the United Nations (UN) and regional blocks such as the European Union (EU) have drafted agreements which provide guidelines on the conservation of the environment. Member nations commit themselves by signing and implementing these agreements. Most of the agreements are legally binding for countries that have formally ratified them. Such agreements include the Kyoto Protocol which was agreed upon in Kyoto, Japan on December 11, 1997.

In 2005, several countries of the world signed the Kyoto Accord whereby they agreed to reduce the amount of greenhouse gases they emit. More than 80 countries, including Tanzania, signed the accord. Most countries have now ratified the Kyoto Protocol. Fun enough, USA, the major world producer of greenhouses gases, has never signed the protocol!

10. Personal involvement

It is crucial that everyone gets involved in the conservation of the environment at individual level. Each citizen should feel obliged to take part in conserving the environment. We cannot let the task be done by the government, agencies and the international organizations alone. This is because we are all involved in environmental destruction, and the effect of this destruction affects all of us.

Good Agricultural Methods

The Ways in which you can Participate in Environmental Conservation

1. Plant more trees at home and farm fields, school and village forest. Do not cut down tress indiscrimately because doing so leaves the soil bare and vulnerable to soil erosion.
2. Always dump litter in areas designated for waste disposal and in litter bins. Do not just throw dirt anywhere and carelessly.
3. Do not start fires near forests. Farmers should not prepare their farm fields by burning the vegetation because the fire can spread and destroy trees and nearby forests. Fire also kills important soil micro-organisms, thus curtailing soil fertility and productivity.
4. Do not harm domestic and wild animals by any means. Be kind to animals and treat them humbly.
5. Convey environmental conservation education to all people. Let them know the importance of conserving and living in a clean environment.
6. Participate in environmental conservation programmes and tasks. These include World environment Day (June 5, every year) and clear-up exercises in the local area or town.

Environmental Conservation and Management at School Level

This part is practically based on organizing students in groups to practice various ways of conserving the environment such as planting trees or flowers, and cleaning environment around the school compound. The responsibility of protecting our dear planet Earth should start from the domestic to international level. Schools have a very unique role in environmental conservation. Environmental management education should be incorporated in national curriculum. Also students should be nurtured to preserve the environment from the primary school level. 

Students Planting Trees in a School





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