Saturday, December 5, 2009

Island-scale adaptation to prevent and reverse desertification

The prevention of desertification in small islands is direly important because of its small land area. Thus measures to combat the turning of arable of productive land into arid and non-productive are a no-no especially for small islands. Each parcel of land is especially important and must be safeguarded.

An important premise upon which this notion is based is prevention. The ‘prevention is better than cure’ catch-phrase applies most significantly in this case. Combating desertification must be an ongoing effort bringing together all stakeholders but especially the inhabitants of deserted areas and policy makers. By working with science and through the populations of the area, much can be achieved to prevent this ecological disaster from occurring.

A key method to prevent desertification, not less in small islands, is the integrated management of land and water especially those which protect soils from erosion and salinization- which are practically the prime causes of desertification. Thus, land practices which prevent overgrazing (such as using grazing species which only consumes the top part of the grass and preventing livestock from grazing the same area repeatedly so as it has time to recover), overexploitation of plants and trampling of soils. A very important aspect of preventing desertification is a sustainable use of water use in agricultural irrigation.

Unsustainable irrigation practices can exacerbate water resources, depleting the aquifers of their water and thus turning the surrounding land into a biological desert because of a lack of water. This will be especially pronounced with the onset of climate change and its subsequent extreme weather conditions which will accentuate drought.

Some important solutions include transhumance of rangelands and well sites which involves the rotational use of these important resources, the rate of stock extracted be less than the carrying capacity of the ecosystem and diverse species composition.

The management of water is also of utmost importance and this can include traditional water-harvesting techniques, water storage and efficient water conservation measures. The latter can be especially applied during intensive rainfall episodes in preventing the water from being lost as surface run-off which also carries away the thin, fertile, moisture-holding topsoil.   

Protecting the vegetative cover is also instrumental since vegetation protects soil from wind and water erosion. A loss of vegetation can also lead to reduced rainfall.
Other measures can include:
  • Mixed farming practices combining livestock rearing and cropping so as to ensure a more efficient recycling of nutrients. For example, fodder can be sowed and thus prevent the pressure of livestock on the land.
  • Applying traditional technology to work with ecosystems since traditional knowledge was more in sync with natural processes.
  • Turning to alternative livelihoods that are not as demanding on the land such as dryland aquaculture and tourism. 

Can we rehabilitate a deserted and arid land?

The main challenge of rehabilitation is to restore ecosystem services that have been lost. Thus one seeks to repair damages sectors of the ex-native ecosystem so that it will then have multiple benefits. This involves the efforts of a multi-tier system from the government and policy makers to the inhabitants of this area. This interlinking is vital as the process is complex and involves, amongst others, seed banks, restocking of soil organic matter and organisms that promote higher plant establishment and growth and the reintroduction of selected species.
Other rehabilitation practices include: 
  • Terracing to counter soil erosion;
  • Control of invasive species which can be more hardy and extract more water;
  •   Nutrient replenishment;
  • Reforestation

 Policies that create incentives for rehabilitation include capacity building, capital investment and supportive institutions. It is very important, as discussed above, that the community is involved throughout the whole process. 

This blog is the result of a workshop held in Bahrija Oasis between the volunteers of the Youth in Action Project 'Go with the Flow'.

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