Land resources: Land as a resource, land degradation, man induced land slides– soil erosion and desertification-Role of an individual in conservation of natural resources-Equitable use of resources for sustainable life style

 6

 Land resources: Land as a resource, land degradation, man induced land slides– soil erosion and desertification-Role of an individual in conservation of natural resources-Equitable use of resources   for sustainable life style

Land is viewed as fixed and finite. There are varieties of biophysical processes and ever more complex linkages to anthropogenic systems and economies that shape land use changes over time. Of special interest from an environment-development perspective are the processes of land degradation, deforestation and desertification observed in many low-income countries.

Land degradation is often closely connected to poverty, climate change and vulnerability, particularly in poorer countries. Slash and burn agriculture, excessive use of charcoal and other unsustainable land use practices are contributing to entrenched poverty in rural areas as well as emissions. Whereas the rich world tends to focus on fossil fuels and climate mitigation, land use change is the major source of emissions in most developing countries as well as a major driver of vulnerability to climate change. The number of people living on degraded agricultural land has been decreasing in the rich world in recent years but has been increasing significantly in poorer countries, especially in sub-Saharan Africa. It is estimated that up to 40% of the world's agricultural land is seriously degraded

Land degradation is a broad term that can be applied differently across a wide range of scenarios. There are four main ways of looking at land degradation and its impact on the environment around it:

A temporary or permanent decline in the productive capacity of the land. This can be seen through a loss of biomass, a loss of actual productivity or in potential productivity, or a loss or change in vegetative cover and soil nutrients.

Action in the land's capacity to provide resources for human livelihoods. This can be measured from a base line of past land use.

Loss of biodiversity: A loss of range of species or ecosystem complexity as a decline in the environmental quality.

Shifting ecological risk: increased vulnerability of the environment or people to destruction or crisis. This is measured through a base line in the form of pre-existing risk of crisis or destruction.

In addition to the usual types of land degradation that have been known for centuries (water, wind and mechanical erosion, physical, chemical and biological degradation), four other types have emerged in the last 50 years: pollution, often chemical, due to agricultural, industrial, mining or commercial activities; loss of arable land due to urban construction, road building, land conversion, agricultural expansion, etc.; artificial radioactivity, sometimes accidental; land-use constraints associated with armed conflicts.

Overall, more than 36 types of land degradation can be assessed. All are induced or aggravated by human activities, e.g. sheet erosion, silting, aridification, salinization, urbanization, etc.

Causes

1.     Land clearance, such as clearcutting and deforestation

2.     Agricultural depletion of soil nutrients through poor farming practices

3.     Livestock including overgrazing and overdrafting

4.     Inappropriate irrigation and overdrafting

5.     Urban sprawl and commercial development

6.     Vehicle off-roading

7.     Quarrying of stone, sand, ore and minerals

8.     Increase in field size due to economies of scale, reducing shelter for wildlife, as hedgerows and copses disappear

9.     Exposure of naked soil after harvesting by heavy equipment

10.  Monoculture, destabilizing the local ecosystem

11.  Dumping of non-biodegradable trash, such as plastics

12.  Invasive Species

13.  Soil degradation, e.g. Soil contamination

14.  Soil erosion

15.  Soil acidification

16.  Loss of soil carbon

Land degradation

Land degradation is caused by multiple forces, including extreme weather conditions particularly drought, and human activities that pollute or degrade the quality of soils and land utility negatively affecting food production, livelihoods, and the production and provision of other ecosystem goods and services.

These social and environmental processes are stressing the world's arable lands and pastures essential for the provision of food and water and quality air. Land degradation and desertification can affect human health through complex pathways. As land is degraded and in some places deserts expand, food production is reduced, water sources dry up and populations are pressured to move to more hospitable areas. The potential impacts of desertification on health include:

·         higher threats of malnutrition from reduced food and water supplies;

·         more water and food-borne diseases that result from poor hygiene and a lack of clean water;

·         respiratory diseases caused by atmospheric dust from wind erosion and other air pollutants;

·         the spread of infectious diseases as populations migrate.

 

Soil erosion and Desertification

Soil erosion is the process of removal of superficial layer of soil. Soil erosion removes soil components and litter.

Harmful effects of soil erosion

1. Soil fertility is lost
2. Loss of soil ability to hold water and sediment
3. Sediment runoff can pollute water courses and kill aquatic life

Types of soil erosion

1. Normal erosion: This is caused by the gradual removal of topsoil by natural processes. The rate of erosion is slow.
2. Accelerated erosion: This is caused by man made activities. In this case, the rate of erosion is much faster than the rate of formation of soil.

Causes of soil erosion

1. Water: Water affects soil erosion in the form of rain, run-off, rapid flow or wave action
2. Wind: Wind is an important climate agent that carries away the fine particles of soil thereby contributing to soil erosion.
3. Biotic agents: Overgrazing, mining and deforestation are the major biotic agents causing soil erosion. These processes disturb the top soil thereby exposing the soil to various physical forces inducing erosion
4. Landslides cause soil erosion

Construction of dams, buildings and roads removes the protective vegetal cover leading to soil erosion.

Human activities have increased by 10–40 times the rate at which erosion is occurring globally. Excessive (or accelerated) erosion causes both "on-site" and "off-site" problems. On-site impacts include decreases in agricultural productivity and (on natural landscapes) ecological collapse, both because of loss of the nutrient-rich upper soil layers. In some cases, the eventual end result is desertification. Off-site effects include sedimentation of water ways and eutrophication of water bodies, as well as sediment-related damage to roads and houses. Water and wind erosion are the two primary causes of land degradation; combined, they are responsible for about 84% of the global extent of degraded land, making excessive erosion one of the most significant environmental problems worldwide.

Intensive agriculture, deforestation, roads, anthropogenic climate change and urban sprawl are amongst the most significant human activities in regard to their effect on stimulating erosion.^[4] However, there are many prevention and remediation practices that can curtail or limit erosion of vulnerable soils.

Landslides

Landslides are the downward movement of a slope composed of earth materials such as rock, soil or artificial fills. Landslides are also called rock-slide, debris-slide, slump, earth-flow or soil-creep. 

During construction of roads and mining activities huge portions of mountainous fragile areas are cut down and thrown into adjacent areas and streams. These land masses weaken the already fragile mountain slopes leading to man-induced landslides.

Effects of landslides:

1.           Landslides increase the turbidity of nearby streams, thereby reducing their productivity

2.           Destruction of communicative links

3.           Loss of habitat and biodiversity

4.           Loss of infrastructure and economic loss

Causes of landslides

1.           Removal of vegetation - Deforestation in slopes creates soil erosion leading to landslides

2.           Underground mining activities cause subsidence of the ground

3.           Movement of heavy vehicles in areas with unstable slopes causes landslides.

4.           Addition of weight by construction on slopes causes landslides.

5.           Over exploitation of groundwater also leads to landslides.

Role of an individual in conservation of natural resources

a. Conservation of energy:

1. Switch off light, fan and other appliances when not in use.

2. Use solar heater for cooking.

3. Dry the cloth in the sun light instead of driers.

4. Use always pressure cookers

5. Grow trees near the house to get cool breeze instead of using AC and ai cooler.

6. Ride bicycle or just walk instead of using scooter for ashort distance.

 

b. Conservation of water:

1. Use minimum water for all domestic purposes.

2. check the water leaks in pipes and repair them properly.

3. Reuse the soapy water, after washing clothes for washing courtyard, carpets etc.

4. Use drip irrigation.

5. Rain water harvesting system should be installed in all the houses.

6. Sewage treatment plant may be installed in all industries and institution.

7. Continuous running of water taps should be avoided.

8. Watering of plants should be done in the evening.

 

 C. Conservation of soil:

1. Grow different type plants i.e trees, herbs and shrubs.

2. In the irrigation process, using strong flow of water should be avoided.

3. Soil erosion can be prevented by sprinkling irrigation.

d. Conservation of food resources:

1.Cook required amount of food.

2.Don’t waste the food, give it to some one before spoiling.

3.Don’t store large amount of food grains and protect them from damaging insects.

 e. Conservation of forest:

1. Use non timber product

2. Plant more trees

3. Grassing must be controlled

4. Minimise the use of paper and fuel

5.Avoid the construction of dam, road in the forest areas

 

Equitable use of resources for sustainable life style:

Sustainable development means Development of healthy environment without damaging natural resources. Unsustainable development means degradation of the environment due to over utilization of natural resources.

Life style in more developed countries: 22% of world population, 88% of it’s natural resources and 85% of total global income. Consumption is more and pollution is more.

Life style in less developed countries: 78% of world population, 12% of it’s natural resources and 15% of total global income. Consumption is less and pollution is less.

Causes of unsustainability: Main cause – difference between Most developed countries  and Less developed

Sustainable life style:

Renewable resource regimes that combine sustainable land management with integrated ecological responses accomplish something that non-renewable can never do – they replenish rather than diminish the resource base for future generations. At the same time, renewable does not equal sustainable: high dependence on traditional biomass and subsistence agriculture in developing countries contributes to land degradation that traps rural households in poverty. As with the fossil economy, the “natural economy” must also transition to a circular and renewable economy, including a sustainable bioeconomy that uses bio-based materials, maximizes re-use and recycling and maintains soil health.

 

Such an economy will require integrated landscape approaches, such as agroforestry, perennial polyculture and hybrid models of renewable energy and agriculture.

 

Case study

The goal of Land Degradation Neutrality (LDN), which aims for no net land degradation, has been in focus due to the recent 13th Conference of the Parties (COP13) to the UN Convention to Combat Desertification (UNCCD) in Ordos, China. During the conference, the Land Degradation Neutrality Fund (LDN Fund) was launched with an initial target of US$300 million, aiming to leverage public money to raise private capital for sustainable land management and landscape restoration activities in support of SDG 15, “Life on Land.” The science-policy basis for Land Degradation Neutrality and related land use issues were also supported through the recent launch of the first Global Land Outlook.

Overcutting of vegetation occurs when people cut forests, woodlands and shrub lands—to obtain timber, fuelwood and other products—at a pace exceeding the rate of natural regrowth. This is frequent in semi-arid environments, where fuelwood shortages are often severe.

Overgrazing is the grazing of natural pastures at stocking intensities above the livestock carrying capacity; the resulting decrease in the vegetation cover is a leading cause of wind and water erosion. It is a significant factor in Afghanistan. The growing population pressure, during 1980-1990, has led to decreases in the already small areas of agricultural land per person in six out of eight countries (14% for India and 21% for Pakistan).

Significant land degradation due to climate change from seawater inundation, particularly in river deltas and on low-lying islands, is a potential hazard that was identified in a 2007 IPCC report.

Threats to land integrity: Land degradation has accelerated during the 20th century due to increasing and combined pressures of agricultural and livestock production (over-cultivation, overgrazing, forest conversion), urbanization, deforestation, and extreme weather events such as droughts and coastal surges which salinate land. Desertification, is a form of land degradation, by which fertile land becomes desert.