30 avril 2009 | EN
Dryland ecosystems are extremely vulnerable to land degradation and desertification
Sustainably developing drylands means balancing local knowledge, science and conflicting demands, says Elena María Abraham.
Dryland ecosystems, which cover one third of the world's land area, are extremely vulnerable to over-exploitation, inappropriate land use and, consequently, land degradation and desertification.
Developing countries are the most affected because poverty, political instability and territorial imbalance worsen the fragility and slow recovery of their drylands. Deforestation, overgrazing andinappropriate irrigation — widely practiced in drylands across the developing world — all also help to undermine land productivity.
Yet for many countries — from the dry Andes in South America to the desert regions of North Africa — developing their drylands is an essential part of boosting national production and improving quality of life for local communities.
To make such development sustainable, decision-makers, scientists and society must share a common vision. Discussing and agreeing on a model for dryland development is essential if we are to balance drylands' ecological complexity against local populations' needs and demands.
But which development model to choose? The extremes range from major investments in capital and infrastructure that transform the natural conditions of drylands and separate society from nature, for example Gulf megacities such as Dubai, to no modifications to the ecosystem at all, for example as supported by groups of radical ecologists opposed to any kind of intervention.
Midway between these two lies a vision of sustainable dryland development, aimed at social equity and 'territorial balance'. It proposes 'development in patches' — attempting to balance drylands' potential to meet people's demands against the need to maintain the territory's ecological integrity. This model concentrates development in the parts of dryland areas with the least restrictions and best conditions for settlement and production — such as corridors, wadis, oases or terraces — while restoring or preserving the rest of the territory. The Gobabeb research centre in the Namibian desert has successfully implemented such an approach.
Whatever model is chosen, decisions must be based on sound science and technology. And this science should be committed to reality and must draw on local knowledge from communities who have learnt to live in such extreme conditions.
Dryland development models need to incorporate deep knowledge of the individual dryland ecosystem, its capacity for resilience and the desertification processes affecting it. This means not only focusing on local processes, but also addressing problems that may have their roots in wider issues, ranging from climate change to upstream water use.For example, climate change predictions for the dry Andes suggest increased summer rainfall, more frequent mudflows and diminishing water supplies as glaciers shrink, all leading to profound changes in the environment and the economy.
Understanding desertification problems needs organised, multidisciplinary research across many fields of natural and social sciences. For developing countries, where national agencies may be partial, bureaucratic and uninterested in environmental issues, this often requires reliance on international cooperation. For example, the Land Degradation Assessment in Drylands project, started in 2006 by the UN Environment Programme and the UN Food and Agriculture Organization, brings together international organisations, universities, research centres and others together to create a global baseline for dryland monitoring.
But even these collaborations are vulnerable to the ups and downs of donor country policies and can suffer cutbacks during financial downturns — such as the current global crisis. For example, important projects in Argentina suffered when Argentine-German scientific cooperation on desertification was shut down after several years of collaborative work.
Withdrawing support in this way can undermine the credibility of the scientists involved in projects and disrupt the continuity of long-term assessment and monitoring. Local communities may feel themselves to be pawns in scientific experiments for knowledge's sake rather than for improving their income or quality of life.
And once problems are diagnosed, mitigating them means involving stakeholders beyond science. Scientists, local communities, decision-makers and the wider society all have a role to play in ensuring that dryland development models are sustainable.
Guided by scientific experts, decision-makers must promote the development model chosen and implement commonly agreed decisions without distorting the proposals. For many developing countries this may mean giving broader environmental policies bigger budgets and higher priority, and will almost certainly mean balancing multiple sector interests and saying 'no' to some stakeholders where pressures conflict.
Overall, society must give more priority to environmental issues, which are often dismissed in the pressure to meet basic needs such as food, security and health care. And society must also take up a more considerate position with those people and places most affected by desertification. Yet it must keep strong control over policies and actions taken, so that none depart from the road to sustainability.
We can travel this road only with the support of science and through the willing interaction of all these actors. Based on their shared vision, we can achieve a model for developing drylands that ensures continued production without desertification.
Elena María Abraham is deputy director of the Argentine Institute for Arid Lands Research.
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