Fragile environments and climate change

Fragile

A term used to describe those natural environments that are sensitive to and easily abused by human activities

Adaption (to climate change)

Changing lifestyles and economic activity to suit a different climate, such as farming different crops or installing air conditioning

Agro-Forestry

Combining agriculture and forestry, as in the planning of windbreaks in areas suffering from wind erosion or growing trees for fuel

Clear Felling

The practice of cutting down all trees on a site

Deforestation

The felling and clearance of forested land by humans

Desertification

Thespread of desert-like conditions into semi arid areas

Drought

A long, continuous period of dry weather (below average rainfall)

Ecological footprint

The impact a person or community has on the environment, expressed as the amount of land required to sustain their use of natural resourses

Famine

A widespread shortage of food, in worse cases it can lead to starvation and even death

Fossil Fuel

Hydrocarbon fuels such as coal, oil and natural gas that cannot be “remade,” because it will take tens of millions of years for them to form again

Global Warming

A slow but s rise in the earths temperature, it may be caused or partly caused by the increase in atmospheric carbon dioxide and other greenhouse gasses, which increase the greenhouse effect

Greenhouse effect

The warning of the earths atmosphere due to the trapping of heat that would otherwise be radiated back into space, its vital to the survival of like on earth

Malnutrition

When people lack a balanced, sufficient diet, often not getting enough good or lacking key nutrients

Migration

When people move from one area to another. The UN defines this as moving for more than 1 year

Orbital Changes

Changes in the way the earth orbits the sun, on very long timescales which can change the earths climate

Overgrazing

Putting too many animals on grazing land so that the vegetation cover is gradually destroyed

Permaculture

A type of agriculture that is both high-yielding and sustainable because it is based on and takes advantage of natural ecological processes

Population pressure

When there’s too many people for the resources (water, farming) of an area to support

Selective Logging

The felling, at intervals, of mature trees in a forest of mixed age, or the extraction of the most valuable trees from a forest

Solar Logging

Changes in the energy emitted by the sun (seen as changing sunspots of the sun’s surface) which can alter earth’s climate

Soil Erosion

The removal of soil by wind and water by the movement of soil down slope

Sustainability

Actions that minimize the negative impacts on the environment e.g pollution and promoting human health

The free processes that are responsible for making environments more fragile

1. Soil erosion

2. Desertification

3. Deforestation

Top 5 countries with the highest ecological footprints

1. China - 5.1B Hectares

2. U.S.A - 2.6B Hectares

3. India - 1.5B Hectares

4. Russia - 848M Hectares

5. Brazil - 551M Hectares

Examples of Fragile environments

• Arid and semi arid environments

• Tropical rainforest

• Cold environments

• Coral reefs

How arid and semi-arid environments fragile

The lack of precipitation and moisture reduces the environment’s ability to recover if damaged

How tropical rainforests are fragile

Deforestation and wildfires lead to large areas being cleared. Infertile soils make it difficult for plants to re-establish

How cold environments are fragile

Low temperatures reduce the ability of the environment to recover as plants cannot regrow

How coral reefs are fragile

Pollution and damage by tourists kill the coral and it struggles to re-establish

Natural causes of desertification

• Soil erosion which leads to loss of nutrients.

• Rainfall patterns becoming less predictable, leading to drought

• Reduced vegetation leading to less nutrients in the soil

• Any rainfall happens in short, intense bursts

Human causes of Desertification

• Overgrazing leading to all the vegetation due to the numbers of animals or the land not having the chance to recover

• Overcultivation leading to nutrients being taken up by crops leaving none for future vegetation to grow

• Deforestation removing shade for soil and there is no roots to bind the soil together, increasing erosion whilst decreasing infiltration and interception

• Population Growth puts increased pressure on the land since people raise more animals and grow more crops

Soil Erosion

The washing/blowing away of top soil, reducing fertility of the remaining soil. Its a natural process which is worsened by humans

Wind Erosion

In drier parts, the wind can easily blow away the dry soil, eroding it

Sheet erosion

Usually occurs in parts of the world where there is moderate rainfall, when rain falls on the bare soil it begins to was away the top of the soil

Gully erosion

Takes place in areas with high rainfall occurs, such as during tropical storms, this high around of water can cut gillies in slopes, often in lands with little vegetation

Natural causes of desertification

• Soil erosion

• Rainfall Patterns

• Reduced Vegetation

Human causes of desertification

• Over-grazing

• Over-Cultivation

• Deforestation

• Population pressure

Sahel

A narrow belt of land in northern-central Africa, spanning across an arrange of countries bordering the southern edge of the Sahara desert. It’s a semi-arid climate, which is always hot, but still sometimes able to have enough rainfall for shrubs, and plants to grow.

Sahel region covers

• Senegal

• Mauritian

• Mali

• Burkina Faso

• Niger

• Nigeria

• Chad

• Eritrea

• Sudan

What happened to the sahel

Before the 1960’s the land was doing well, rainfall was enough, crops and plants could grow, however there was a big population increase which put pressure to strip the land of more resources to manage the population. The climate began to decline with people still putting pressure on the land. After the 1970s crop failure became normal along with droughts, leading up to the deaths of around 100,000 people

Natural causes of deforestation

• Tree diseases

• Forest fires

• Extreme weather

• Parasites

Human causes of deforestation

• Building of settlements

• Agriculture

• Road Building

• Logging

• Mining

• Hydro-power (Building damns and reserves)

Consequences of soil erosion

• Malnutrition rises

• Migration away from the land

• Famine and starvation

• International aid needed