Land Degradation of the steppe, China

Steppe

  • a dry, grassy plain
  • occurs in temperate climates between the tropics and polar regions
  • mostly found in USA, Mongolia, Siberia, Tibet and China
  • long cold winters (-40℃) and short hot summers (38℃)
  • semi-arid with 20-25cm of rain /yr
  • prone to drought, strong winds and intense thunderstorms #

In the steppe area of China:

  • previously occupied by nomadic pastoralists who moved around the grassland with herds of domesticated animals (horses, cattle, sheep)
  • herds adapted to the natural environment
  • the size of the herd was key in order to keep the natural system in balance
  • growing steppe communities needed cereals and vegetables to supplement their meat and milk based diet
  • they had limited trading options so they organised themselves into farming units #
  • continued population growth in urban and rural areas of China meant the state offered incentives such as tax cuts to farmers in order to expand the agriculture sector and meet the food demands in urban areas
  • investment by the state into agricultural technology and trade in agricultural products led to more growth in food production
  • new crops like corn from North America could be grown in areas that previously couldn't support traditional Chinese crops so it brought marginal land into production
  • it was driven by state objective to ensure national food security and rural stability
  • it was intensified further by the use of fertilisers and chemicals and infrastructure investment #

Growth in cultivated crops gradually resulted in land degradation as the fragile steppe was overexploited by:

  • OVERGRAZING as more animals than the land can support and less mobility due to changes in land tenure
  • OVERCULTIVATION as grasslands removed, land degraded with chemicals and fertilisers, ploughing destroying soil structure and leading to erosion of the nutrient rich top soil

Despite the success of some land-management practices
the rate of land degradation > environmental restoration
This threatens China's overall long-term development and standard of living

Impacts of land degradation

Environmental

Economic

Socio-cultural

Desertification of 2500km² land annually (long term impact) is caused by:

  • erosion of 5 billion tonnes of top soil per year (by the physical processes of water and wind erosion)
  • chemical degradation of land due to the process of salinisation

Biological degradation from pollution and infestations impact on biodiversity long term

Loss of soil and nutrients through wind and water erosion due to exposure of soil due to cultivation and overgrazing

  • x20 increase in the frequency of strong winds in China in the 1990s
  • nutrients washed away = 54 million tonnes of fertiliser

Increased sedimentation of rivers

Addition of fertilisers and chemicals pollutes water sources and further degrades soils
2 million ha of pasture land degraded each year

Drilling of deep wells for irrigation reduces the water table, leads to soil degradation and salinisation

Overgrazing:

  • Leads to the compaction and hard setting of the soil by grazing animals which causes physcial degradation of the land, reduces infiltration and increases run-off which lowers the water table and leads to salinisation
  • Reduces vegetation cover and results in an environment that favours rodent and weed infestations

Reduced income from traditional economies
Direct economic loss valued at $6.5billion

Increased dependancy on food aid

Increased rural poverty

Expansion of agricultural land due to diminishing returns season by season

Loss of traditional skills

Forced migration due to food insecurity

Tension in receipt areas of migrants

Solutions to land degradation #

Overgrazing

Strategies for prevention:

  • Improved stock quality: vaccination programmes and introduction of better breeds, yields of meat, wool and milk can be increased without increasing the herd size
  • Better management: reducing herd sizes and grazing over wider areas would reduce soil damage

Problems and drawbacks:

  • Vaccination programmes improve survival rates, leading to a bigger herd
  • Population pressure often prevents these measures

Overcultivation

Strategies for prevention:

  • Use of fertilisers: can double yields of grain crops, reducing the need to bring more land into production
  • New or improved crops: new crops or new varieties of traditional crops with high yielding and drought resistant qualities could be introduced
  • Improved farming methods: use of crop rotation, irrigation and grain storage can all increase and reduce pressure on land

Problems and drawbacks:

  • Cost to farmers
  • Artificial fertilisers may damage the soil
  • Some crops need expensive fertiliser
  • Risk of crop failure
  • Some methods require expensive technology and special skills