Land Degradation

Frequently Asked Questions

Barclay's Park

What is Land Degradation?

Land degradation is a process in which the value of the biophysical environment is affected by one or more combination of human-induced processes acting upon the land.  It is viewed as any change or disturbance to the land perceived to be deleterious or undesirable.  Natural hazards are excluded as a cause, however human activities can indirectly affect phenomena such as floods and bushfires.

This is considered to be an important topic of the 21st century due to the implications land degradation has upon agronomic productivity, the environment, and its effects on food security.  It is estimated that up to 40% of the world’s agricultural land is seriously degraded.

How is it Measured?

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.

A decline in the lands “usefulness”: A loss or reduction in the lands 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.

A problem with measuring land degradation is that what one group of people call degradation, others might view as a benefit or opportunity. For example, heavy rainfall could make a scientific group be worried about high erosion of the soil while farmers could view it as a good opportunity to plant crops.

What are the Common Causes?

  • Land degradation is a global problem, largely related to agricultural use. The major causes include:
  • Land clearance, such as clearcutting and deforestation
  • Agricultural depletion of soil nutrients through poor farming practices
  • Livestock including overgrazing and overdrafting
  • Inappropriate Irrigation[6] and overdrafting
  • Urban sprawl and commercial development
  • Land pollution including industrial waste
  • Vehicle off-roading
  • Quarrying of stone, sand, ore and minerals

What are it’s Effects?

The main outcome of land degradation is a substantial reduction in the productivity of the land.[7] The major stresses on vulnerable land include:

  • Accelerated soil erosion by wind and water
  • Soil acidification and the formation of acid sulfate soil resulting in barren soil
  • Soil alkalinisation owing to irrigation with water containing sodium bicarbonate leading to poor soil structure and reduced crop yields
  • Soil salination in irrigated land requiring soil salinity control to reclaim the land [8]
  • Soil waterlogging in irrigated land which calls for some form of subsurface land drainage to remediate the negative effects [8]
  • Destruction of soil structure including loss of organic matter

Overcutting of vegetation occurs when people cut forests, woodlands and shrublands—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.

Agricultural activities that can cause land degradation include shifting cultivation without adequate fallow periods, absence of soil conservation measures, fertilizer use, and a host of possible problems arising from faulty planning or management of irrigation. They are a major factor in Sri Lanka and the dominant one in Bangladesh.

The role of population factors in land degradation processes obviously occurs in the context of the underlying causes. In the region, in fact, it is indeed one of the two along with land shortage, and land shortage itself ultimately is a consequence of continued population growth in the face of the finiteness of land resources. In the context of land shortage 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 22% for Pakistan).

Population pressure also operates through other mechanisms. Improper agricultural practices, for instance, occur only under constraints such as the saturation of good lands under population pressure which leads settlers to cultivate too shallow or too steep soils, plough fallow land before it has recovered its fertility, or attempt to obtain multiple crops by irrigating unsuitable soils.

High population density is not always related to land degradation. Rather, it is the practices of the human population that can cause a landscape to become degraded. Populations can be a benefit to the land and make it more productive than it is in its natural state.

Severe land degradation affects a significant portion of the Earth’s arable lands, decreasing the wealth and economic development of nations. As the land resource base becomes less productive, food security is compromised and competition for dwindling resources increases, the seeds of famine and potential conflict are sewn.

What is the UNCCD?

Following a Cabinet Decision of 03 April 1997, Barbados acceded to the Convention on August 12, 1997.  The Convention is the principle international instrument addressing the global problem of land degradation and drought. The National Committee was convened and has undertaken an important role as a project steering Committee. The multi-sectoral  committee includes in addition to the agencies of the Ministry of Environment and Drainage, representatives from Ministry of Agriculture, Tourism, Foreign Affairs,  Economic Affairs and the National Trust.