Environment

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The Nature of Traditional Societies

The Use & Ownership of Land

Division of Labour & Types of Tools

Social & Cultural Activities and Dependence on Local Environment

The Impact of Colonialism

Peasant Farming/Subsistence Farming

Subsistence farming refers to the practise of using land to grow food for consumption by the family. There is very little if any to sell. Subsistence farmers may barter for other products that they need. It is common in poor countries.

Subsistence farmers cannot afford to invest in capital to increase their yields to the point of having produce to sell. The farming methods they use are often very basic and labour intensive.

In Tanzania many families have small plots if land which is often of poor soil quality and they grow cassava. The tools they use are basic such as hoes, spades, and rakes. These are cheap to buy and easy to maintain.

Cash Cropping

This refers to the growing of crops that can be sold for money rather than used for food. Subsistence farmers have often turned to cash crops to generate income. Coffee growing in Costa Rica, cocoa in Ghana and vanilla in Indonesia are examples of crops grown for sale (often export).

Whilst it may provide a route out of poverty it is highly dependent on the global supply and demand for the crop. Many coffee growers have suffered falling prices as the global supply drastically increased when many farmers started to grow coffee. This leaves the growers with insufficient income to live off and if they have invested money (often borrowed) in machinery, irrigation, chemicals (fertilisers & pesticides ) they may end up unable to repay the loans and possibly loose their land.

Commercial Farming

Commercial farming spans a huge range of examples. Garden vegetables such as beans and peas are grown commercially in Kenya and flown to Europe straight after being picked and processed. This allows them to take advantage of low labour and land costs.

Pineapples and bananas are grown commercially in plantations on the East side of Costa Rica by companies such as Del Monte and Chiquita. The warm climate, fertile soils, plentiful rain and cheap labour costs attracted these companies to invest there.

Tanzania has commercial farming of sugar cane and sisal (used for making ropes and textiles).

Commercial farming in developing countries is typically large in scale but relatively labour intensive.

Farming has become increasingly commercialised in developed countries as they invest heavily in capital and increase the size of the farms to benefit from economies of scale. There tend to be high levels of inputs such as fertilisers, pesticides, herbicides, irrigation and machinery in commercial farming in developed countries.

Increasing use of technology and computers is common in commercial farming with satellites and GPS systems guiding tractors and combine harvesters, this increases the efficiency of spraying chemicals and harvesting. Computer models are being created which display the yield from different areas of fields and different fields, this is linked with soil samples and charts displaying the nutrient contents of different areas of fields. All this data allows farmers to deliver specifically tailored chemicals and amounts to different areas of the fields to maximise output and efficiency.

Development of Monoculture & Large-scale Projects

Plantations

Rural Development Schemes

Loans & Credit Schemes and Small-scale Rural Projects

Farmers’ Co-operatives

Resettlement Schemes

Integrated Rural Development

Mobilisation of rural population

Grass roots’ development

Appropriate farming methods

Population Growth & Changing Demand on Food Supplies

Population growth is increasing the demand for food in the world. There are more significant changes that impacting on the demand for food though. Population growth is highest in many LEDCS and NICs. China and India have the largest populations on the planet and their increasing levels of development are leading to rising income s for the populations. Whilst this is good news in most respects it is also leading to changes in their diets. With increased incomes they can afford to add meat more regularly to their diet. Producing meat requires vast amounts of grain, and provides the ability to feed far fewer people than if the grain had been consumed by humans. This change is decreasing the available grain supplies which will push up the price of staple foods that the poor rely on.

Biofuels are also having a significant impact on food supplies. Increasing amounts of wheat have been used to produce biofuels, this has significantly reduced the amount produced for food, this is pushing up the price of wheat for food consumption. Large areas of land that could be used for food production are being turned over to biofuels such as wheat, palm oil and sugar cane.

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Modernisation of agriculture to increase output

Pesticides: Chemicals have been developed that target specific insects that may affect crops. These are used intensively in plantations to prevent crops being destroyed/damaged.

Fertilisers: nitrates and phosphates are commonly used to replenish depleted nutrient in the soil. Intensive plantation farming quickly depletes the soil and fertilisers are used to increase crop growth rates an the yields from the crops.

Irrigation: a major aspect of the green revolutions success. Irrigation has vastly increased output of grain crops in India and Mexico. It is used throughout the world to increase yields and grow crops that otherwise would not thrive.

Land reform

Plant breeding

GM crop

Hydroponics

Animal breeding & production programmes

Transport, Preserving & Freezing

Cash Crops Vs Staple Foods for Local Populations

Flight From the Land

Land Degradation

Overgrazing: increased livestock numbers overgraze the land, leaving bare patches of soil which are then eroded by wind & rain. Trampling by livestock kills vegetation & compacts soils.

Deforestation: removal of trees for agriculture/timber reduces interception of rain & leaves soils exposed to erosion. Many of the nutrients are stored in trees.

Mono-cultures: plantations of single crops remove specific nutrients which are not replaced as the vegetation is taken away to be sold.

Irrigation: in arid areas high evaporation rates draw water upwards and this brings salts with it causing salinisation. Soil erosion: soil removed by the wind and/or water takes a very long time to be replaced naturally. Ploughing fields leaves the soil exposed to the elements and increases the risk of erosion.

Pesticide and nitrate pollution

Eutrophication: leaching of fertilisers into rivers can cause excess growth of algae; this can deplete the river of dissolved oxygen & block out sunlight causing the death/depletion of many other plants & fish in the river.

Sustainability of Modern Farming Systems

Plantations

These are often large in size and are mono-cultures. Bananas in the Caribbean, coconuts in East Africa, tea in India and China are examples. Modern plantations of palm oil are being established in many tropical countries (Indonesia & Costa Rica). These are damaging the ecosystem since they cannot support the diversity of wildlife that would have existed in the natural vegetation. They also deplete the soils of certain nutrients. In these sense they are unsustainable and often need the input of fertiliser and pesticides which cause further damage to the ecosystem and water supplies.

Organic farming

Increasing Population Leading to Deforestation

Most developing countries are experiencing rapid population increases. This is often leading to deforestation for a range of reasons. In rural areas housing is often built from timber, the lack of reliable power supplies and the cost of electricity lead to many families using wood or charcoal as a cooking and heating fuel.

As populations increase there is the demand for an increase in food supplies. Previously wooded land is often cleared to make way for pasture for livestock or land for arable farming.

Forced use of Marginal Land Leading to Desertification

Areas that are naturally arid have been under increasing pressure as population growth forces people into these areas.
This land is then used for grazing increasing numbers of cattle, goat and sheep. These strip the fragile vegetation and trample the ground which damages the plants and compacts the soil.
This leads to the soil being exposed, subjected to erosion (by wind and water) and subsequent degradation.
Once the soil is degraded vegetation growth is more limited, leaving the land more exposed.
This overuse of the land is turning arid land in desert which then forces people to overuse other areas of land and the process continues.
Sub-Saharan African countries have been experiencing increasing desertification.

Increasing demand for land for utilities (water & power)

Exploitation of Land for Mineral Extraction

Many LEDCs have significant mineral reserves that are in high demand by international industries. Mineral reserves are essentially non-living naturally forming substances and can include fossil fuels, metal ores. Mineral extraction usually involves removing large areas of the topsoil (and vegetation) and causes significant environmental damage.

Tanzania & Gold Extraction

Located 50km South of Lake Victoria in Tanzania, Geita is the countries largest producing gold mine, operated by South African group AngloGold Ashanti.
It is an open pit mine which means that to reach the gold reserves they have to remove the land above. This is done by blasting through the rocks and has resulted in entire mountains being removed and new ones built with the loose waste rock and soil.
The initial removal of vegetation was harmful to the savannah ecosystem present there & the new mountains being established are unstable.
As the mine goes deeper to reach new gold deposits they need to pump the water out of the mine pit. The planned depths mean that this will increase and is likely to reduce the groundwater level for the surrounding area which will have a negative effect of the hydrology of the region.
In addition to these problems there is a major concern over arsenic contamination of local water supplies and ultimately Lake Victoria. The gold processing uses large quantities of arsenic and this is empties into a tailings dam where it should be broken down by sunlight. However there are reports of this dam leaking and the arsenic entering local rivers and ground water supplies.

Similar projects exist in the Amazon basin as bauxite, gold and silver are extracted. Copper mines are damaging the environment in Zambia, diamond mines in Sierra Leone and South Africa are other examples.

Mass Tourism and Development

Tourism has been rapidly expanding in most areas of the world. Rising levels of disposable income in MEDCs and an emerging middle class in the NICs have led to many more people travelling.

The cost of air travel has also been falling in real terms over the last few decades as planes become much more efficient and airlines save costs through utilising technology (e-tickets, self service check in etc). This has brought financial benefits for tourist destinations.

Many LEDCs have been able to promote and exploit their natural landscapes and wildlife, from safaris in Tanzania and Kenya, Gorilla trekking in Rwanda, to rainforest trekking in Costa Rica and glacier tours in Argentina. Other countries have relied on historical and cultural attractions such as Mexico and Egypt with their pyramids, Laos with the Angkor Watt temples, Peru with the Inca ruins of Machu Pichu.

These countries have been able to attract large numbers of tourists and generate significant amounts of foreign earnings. The tourism industry employs a whole range of people and many of them are relatively unskilled - bus drivers, taxi drivers, waiters, bar staff, cleaners, tour guides and so on. Tourism can create a multiplier effect in the economy and be a good driver of growth. Tourist resorts have sprung up rapidly where there is demand, many of them being owned by MNC hotel chains. While they generate significant income they also bring a raft of problems such as loss of culture, profits being repatriated to the home country of the hotel, environmental degradation and overcrowding of the local places.

Economies that are heavily reliant on tourism face many potential difficulties. Any negative occurrence in the country can dissuade tourisms from coming (the recent troubles in Egypt have decimated its tourist trade). Economic slowdowns in other parts of the world can cause a significant drop in the number of tourist (the recent economic crisis has seen tourists from Europe plummet). Rises in the countries exchange rate can make it comparably more expensive than rival destinations and result in many people choosing not to come.

Evaluate conservation methods: National Parks, Ecotourism, National Forests, Heritage Sites, Areas of Special Scientific Interest, Protection of endangered species CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora):

Deforestation of Tropical Forests

Causes

Logging: legal & illegal for hardwood timbers, worth $ billions each year.
Cattle ranching: in Latin America - high rainfall & initially fertile grasses.
Palm oil & rubber: monoculture plantations with high export values.
Fossil fuels: oil & coal reserves exist under large areas of many rainforest regions.
HEP: large scale hydro-electric dams have been built and more are planned in tropical regions (high rainfall rates and large rivers) which destroys vast areas of rainforest.

Effects on Biodiversity

Tropical rainforests are the home to a vast array of plants, animals and insects. They hold a significant proportion of the worlds biodiversity which is increasingly under threat due to deforestation.

As the forest is removed it initially removes the homes of the animals and insects that lived there. It has wider reaching impacts though as the nutrient cycle is broken and the original rainforest is unable to re-establish itself. The lack of vegetation leads to soil erosion. Without the trees intercepting rainfall and the mass of vegetation transpiring, the humidity levels are likely to reduce which leads to lower rainfall and potential droughts. This is very damaging for the remaining sections of the rainforest. Gaps in the food chains start to appear.

Strategies to Reduce This

Possible Causes of Climate Change

Greenhouse Effect

Theory stating that:

Increased emissions of greenhouse gases (CO2, CFCs, methane, water vapour, ozone & nitrous oxides) from industry, power stations, cars (burning fossil fuels).
The greenhouse layer allows solar radiation (insolation) to pass through easily but traps longer wave radiation that is emitted by the earth.
These gases are making the greenhouse layer thicker. Trapping more of the long wave surface radiation in the atmosphere

Global Dimming

Theory stating that the increased pollution levels in the atmosphere are having a cooling effect on the climate due to increased atmospheric reflection. This is in part to the extra particles in the atmosphere but also due to the particles acting as condensation nuclei in clouds & increasing cloud reflectivity

Solar Radiation Variations

The sun has cycles of increased activity (solar maximum) & decreased activity (solar minimum) that may affect the amount of radiation reaching the Earth & therefore influence the energy balance.

Variations in the Earth’s orbit around the sun & its tilt on its axis are argued to lead to changing climate patterns over long periods of time (Milankovitch Cycles).

Current and Probable Future Impacts

Increased melting of polar & glacial ice - leading to reduced albedo rates & more surface absorption.
Rising sea levels due to polar ice melt & expansion of the seas as they warm.
Increased storms/hurricanes due to warmer sea temperatures. Possible disruption to ocean current systems as polar ice melts.
Thawing of areas of permafrost - peat bogs are predicted to release huge amounts of methane as they thaw.

Strategies to Limit Climate Change and its Impacts

There are a plethora of strategies in place and in planning that aim to reduce the rate and impact of climate change.

International agreements on carbon emission reductions (Kyoto Agreement)
Carbon trading schemes.
Increased taxes on fuels (especially aviation).
Incentives (subsidies and grants) to develop and implement renewable energy technologies.
Increases in efficiencies of products, cars, televisions, lightbulbs etc).

One of the main issues is that the worlds population in increasing rapidly and this is leading to increasing demands for energy - for which fossil fuels are the easiest and cheapest to use.

It is clear that for any of the strategies to be successful they will need international cooperation, and even then it will require countries to adopt several of the approaches.

Many countries are starting to establish strategies for dealing with the effects such as rising sea levels, increased drought or heavy rainfall.

London is looking to improve its Thames barrier which prevents storm surges coming up the river.

Tuvalu (a South Pacific Island) is already evacuating and rehousing some of its population in New-Zealand as high tides are inundating many areas of the low lying islands.

Acid Rain

Acid rain is the result of nitrogen oxides & sulphur dioxides are released as air pollution from transport, industry and power generation. These mix with moisture in the atmosphere and are brought back to earth in the rain as sulphuric acid & nitric acid.

The acid rain often falls a significant distance away from the source of the pollution, commonly in another country.

Acid rain has several damaging effects on ecosystems. Since it falls as rain, some is intercepted by trees and it can damage/burn their leaves/needles. Some of the acid rain infiltrates into the soil layer and is taken up by plants and trees roots which can subsequently cause the trees to suffer. The acid in the water can also increase the leaching of nutrients and minerals out of the soil leaving it degraded. Acid rain can also increase the acidity of rivers and lakes which if significant enough can kill fish and plant life in them.

There are various strategies aimed at reducing the amount of acid in rainwater. Perhaps the most significant is the drive towards reducing the burning of fossil fuels. This linked with increasing the efficiency of many domestic appliances and forms of transport is reducing the pollution being released into the atmosphere in many countries. Technologies have also been created to filter out the harmful gases in the chimneys of power stations and heavy industry.

Causes & Impacts of Urban Air Pollution

Urban air pollution is caused primarily by transport and industry. The burning of fossil fuels in transportation releases a plethora of dangerous gases. We have just seen the causes and impacts of acid rain in the environment. Acid rain also damages buildings in urban areas as it corrodes buildings. Of more concern though is the impact of air pollution on human health. Many cities with high air pollution rates are recording increases in illnesses such as asthma. The European Union has brought in regulations to control air pollution levels in cities, London has so far failed to consistently meet these regulations.

Strategies to reduce such impacts.

London Congestion Charge

This is a strategy that charges a fee for vehicles to enter the central London zone. It is aimed at reducing the amount of traffic entering central London and encouraging people to use public transport or cycle. The money generated by the scheme is used to cover the costs and the remainder invested in improing public transport. An important part of the scheme is reducing air pollution in London since it is required to meet certain standards as set by the European Union.

Water Pollution from Industrial Production and Sewage

Strategies to reduce its impact

Strategies to reduce waste sent to land fill sites

Recycling: many countries are striving to increase the level of recycling within their economies.