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  1. Global Change and Natural Resources Management (BB-507) Desertification Lucio Pedroni 19 August, 2004

  2. Content of this session • Introduction • Causes of desertification • Consequences of desertification • The UN Convention to Combat Desertification • Combating Desertification in Latin America • Links with other global change problems • Conclusions

  3. Introduction • 36 millions km2 in the world are affected by desertification (CR x 670). • 35% of the world land area is at risk of desertification. • 21 millions ha are degraded annually (CR x 4). • About 130 million hectares can no longer be used for food production (CR x 24). • The processes of land degradation and desertification are not new… • Desertification undermines the land's productivity and contributes to poverty. • Desertification is primarily a problem of sustainable development. development.

  4. Arid lands of the world

  5. Regional variations in water scarcity

  6. Desertification is... • As indicated in Article 1 of the UNCCD, "desertification" means land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climatic variations and human activities. • While land degradation occurs everywhere, it is only defined as "desertification" when it occurs in dry-lands. • 70% of the 5,200 million hectares of dry-lands used for agriculture around the world are already degraded (Down to Earth, UNCCD Secretariat).

  7. Importance of various human activities in respect to soil degradation Activity Respective Importance (%) Over-grazing 35% Deforestation 30% other Agricultural practices 28% Fuel wood combustion 7% Industrial development 1% [Source: Daily, 1995].

  8. Soil degradation in non dry-lands is not called “desertification”, although it may have similar causes and effects…

  9. Causes of desertification... • Unsustainable land-use practices. • Natural climatic variability. • Changing capacity of local communities to adapt to dry conditions and climatic fluctuations. • Access to land. • International trade patterns. • Inappropriate technology and policy choices. • Demographic changes. • Conflicts, migrations, refugees camps.

  10. Unsustainable land-use practices…

  11. Climate variability

  12. Fragile and non-fragile lands

  13. Rural population on fragile and non-fragile lands

  14. Soil Degradation Severity

  15. Source: UNEP GRID-Arendal

  16. Consequences of Desertification • Reduced land's resilience to natural climate variability. • Soil becomes less productive. • Vegetation becomes stressed. • Food production decreases causing famine, poverty, spread of diseases… • Ex-situ impacts (flooding, water quality, sediments, dust storms). • Migration, conflicts, environmental refugees.

  17. The Convention to Combat Desertification Late '60s and early '70s: Drought in sub-Saharan Africa: Over 200,000 people and millions of animals die. September 1973: Inter-State Permanent Committee on Drought Control in the Sahel (CILSS) established by 9 Sahelian countries. August to September 1977:United Nations Conference on Desertification (UNCOD) held in Nairobi, Kenya: Desertification addressed as a worldwide problem for the first time and a Plan of Action to Combat Desertification (PACD) adopted. June 1992:United Nations Conference on Environment and Development (UNCED) held in Rio de Janeiro, Brazil:The Earth Summit and Agenda 21 call on the UN General Assembly to set up an inter-governmental committee to prepare for a legally binding instrument that addresses the problem of desertification.

  18. The Convention to Combat Desertification June 17, 1994: United Nations Convention to Combat Desertification (UNCCD) adopted in Paris, France:June 17 becomes the world day to combat desertification. December 1996: The UNCCD enters into force, 90 days after the 50th ratification is received. 1997- today:Secretariat established in Bonn. GEF becomes financial mechanism of UNCCD.

  19. Institutions of the CCD UNCCD Secretariat in Bonn Committee on Science and Technology (CST) Committee for the Review of the Implementation of the Convention (CRIC) Conference of the Parties UNCCD Global Mechanism Observer organizations GEF $ $ NAPs, RAPs, SRAPs

  20. Action Programs to Combat Desertification • March 2002: 57 National Action Plans (NAPs) prepared. • NAPs should be integrated into other development program frameworks. • Participatory, bottom-up approach is emphasized. • Sub-regional and regional programs to support national programs (SRAPs RAPs).

  21. Combating Desertification in Latin America and the Caribbean • 25% of Latin America is desert or dry-land (20,533,000 km², CR x 380). • Poverty is high (110 millions) and generates pressure on and degradation of these lands. • All LA countries have ratified the CCD. • Several countries have prepared NAPs. • UNEP in Mexico City coordinates a RAP. • Central America is preparing a SRAP (CATIE is participating with Dr. Alan González).

  22. Precipitación anual América Central Fuente: USGS, CIAT, ESRI, CINDI

  23. Fuente: CATIE

  24. Fuente: CIAT

  25. Financing Action to Combat Desertification • UNEP: an effective 20-year global effort would cost US$ 10-22 billion per year. • UNEP: desertification costs some US$ 42 billion in income per year. • Founding sources of NAPs: • Affected countries, • Bilateral and multilateral aid, • GEF,

  26. Links with other global change problems • The CCD can and should be implemented in synergy with other development efforts. • Synergy with conservation and sustainable use of biodiversity. • Synergy with water management problems. • Climate change can affect drought patterns. • Desertification can affect local climate. • Desertification increases poverty and political instability.

  27. Conclusions • Desertification is more than the expansion of deserts. • Addressing desertification is closely linked to addressing poverty and land use. • Desertification, climate change and water issues are closely linked: some forecasts that they will be a main source of conflicts in the 21 Century. • Conflict prevention requires to combat desertification.

  28. Thank you

  29. Causes of desertification... • Desertification is the degradation of drylands. • Loss of biological or economic productivity • Due to climate variability and unsustainable human activities (over-cultivation, overgrazing, deforestation, and poor irrigation practices). • 70% of the world's drylands (excluding hyper-arid deserts), or some 3,600 million hectares, are degraded. • Drylands respond quickly to climatic fluctuations. • By definition, drylands have limited freshwater supplies. • Precipitation can vary greatly during the year. • In addition to this seasonal variability, wide fluctuations occur over years and decades, frequently leading to drought. • Over the ages, dryland ecology has become attuned to this variability in moisture; plants and animals can respond to it rapidly. For example, satellite imagery has shown that the vegetation boundary south of the Sahara can move by up to 200 km when a wet year is followed by a dry one, and vice versa.

  30. ...Causes of desertification... • People must also adjust to these natural fluctuations. • The biological and economic resources of drylands, notably soil quality, freshwater supplies, vegetation, and crops, are easily damaged. • People have learned to protect these resources with age-old strategies such as shifting agriculture and nomadic herding. • However, in recent decades these strategies have become less practical due to changing economic and political circumstances, population growth, and a trend towards more settled communities. • When land managers cannot or do not respond flexibly to climate variations, desertification is the result.

  31. ...Causes of desertification... • The relatively low priority given to environmental protection often leads to poor land management decisions. • The overuse of land may result from specific economic conditions or from inappropriate land laws or customs. • In many cases, unregulated access to land resources may lead some individuals to maximise their own gains by overexploiting the land at the expense of the community as a whole. • Poor people, particularly poor women, often lack access to the best land, depending instead on the most fragile areas and resources. • Their poverty may give them little alternative but to extract what they can from the scarce resources available to them, even though this degrades the land.

  32. ...Causes of desertification... • International economic forces can encourage people to overexploit their land. • International trade patterns can lead to the short-term exploitation of local resources for export, leaving little profit at the community level for managing or restoring the land. • Similarly, the development of an economy based on cash crops, or the imposition of taxes, can distort local markets and promote overexploitation of the land. • Ignorance, errors, and natural and man-made disasters can also contribute to land degradation. • Mistakes in the choice of policies or technologies have led to land degradation in many countries, both developed and developing. • Disasters such as wars and national emergencies also destroy productive land by displacing its managers or causing heavy concentrations of migrants to overburden an area. • Natural disasters such as floods and droughts can have a similar effect.

  33. ...Causes of desertification... • What role do increasing populations and population densities play? • It is tempting to conclude that an expanding human population is the ultimate driving force behind desertification. More people in an area inevitably exert a greater pressure on that area's resources; • Sometimes this pressure is indirect, as when growing urban populations place demands on food production in uncrowded rural areas. • But the causes of desertification are complex, and the relationship between two variables such as population and desertification is not clear-cut. • For example, a decline in population can result in desertification since there may no longer be enough people to manage the land adequately. • Many hillside terraces in Yemen have fallen into disrepair with the exodus of labour to neighbouring oil-rich countries. Examples can also be cited of areas that support large concentrations of people without much degradation, such as around the city of Kano in Nigeria.

  34. Consequences of Desertification... • Desertification reduces the land's resilience to natural climate variability. • Soil, vegetation, freshwater supplies, and other dryland resources tend to be resilient. They can eventually recover from climatic disturbances, such as drought, and even from human-induced impacts, such as overgrazing. • When land is degraded, however, this resilience is greatly weakened. This has both physical and socio-economic consequences. • Soil becomes less productive. • Exposed and eroded topsoil can be blown away by the wind or washed away by rainstorms. • The soil's physical structure and bio-chemical composition can change for the worse. • Gullies and cracks may appear and vital nutrients can be removed by wind or water. • If the water table rises due to inadequate drainage and poor irrigation practices, the soil can become waterlogged, and salts may build up. • When soil is trampled and compacted by cattle, it can lose its ability to support plant growth and to hold moisture, resulting in increased evaporation and surface run-off.

  35. ...Consequences of Desertification... • Food production is undermined. • Desertification = major global environmental issue because of its implications on food production. • Food production should triple over the next 50 years. • If desertification is not stopped and reversed, food yields in many affected areas will decline. • Productivity is affected by many different factors (weather, disease and pests, farming methods, and external markets and other economic forces. • Desertification contributes to famine. • Famine typically occurs in areas that also suffer from poverty, civil unrest, or war. • Drought and land degradation often help to trigger a crisis.

  36. ...Consequences of Desertification... • Vegetation becomes damaged. • The loss of vegetation cover is both a consequence and a cause of land degradation. • Loose soil can sandblast plants, bury them, or leave their roots dangerously exposed. • When pastures are overgrazed by too many animals, or by inappropriate types, edible plant species may be lost, allowing inedible species to invade. • Some of the consequences are borne by people living outside the immediately affected area. • Degraded land may cause downstream flooding, reduced water quality, sedimentation in rivers and lakes, and siltation of reservoirs and navigation channels. • It can also cause dust storms and air pollution, resulting in damaged machinery, reduced visibility, unwanted sediment deposits, and mental stress. • Wind-blown dust can also worsen health problems, including eye infections, respiratory illnesses, and allergies. • Dramatic increases in the frequency of dust storms were recorded during the Dust Bowl years in the US, in the Virgin Lands scheme area in the former USSR in the 1950s, and in the African Sahel during the 1970s and 1980s.

  37. ...Consequences of Desertification • Desertification has enormous social costs. • Desertification  movements of people, conflicts. • Increased pressure on the environment around cities and camps where people settle (eg.: In Africa). • Difficult living conditions and the loss of cultural identity further undermine social stability. • Desertification is a huge drain on economic resources. • Little detailed data on economic losses resulting from desertification • Unpublished World Bank: depletion of natural resources in one Sahelian country was equivalent to 20% of its annual Gross Domestic Product (GDP). • The global annual income foregone in the areas immediately affected by desertification amounts to approximately US$ 42 billion each year. • Indirect economic and social costs suffered outside the affected areas, including the influx of "environmental refugees" and losses to national food production, may be much greater.

  38. Action Programmes to Combat Desertification... • The Convention to Combat Desertification is being implemented through national action programmes (NAP). • March 2002: 57 NAPs prepared and adopted. • Efforts to combat desertification should be fully integrated into other development programme frameworks. • Reversing land degradation and alleviating poverty go hand in hand. Both involve improving food security, educating and training people, strengthening the capacity of local communities, and mobilising non-governmental organisations. • Similarly, because desertification affects and is affected by environmental concerns such as loss of biological diversity and climate change, NAPs need to have a great potential to promote synergies with other programmes dealing with such issues. • However, improved data at the country level and stronger recognition of the NAPs have yet to manifest this potential fully through concrete initiatives. Parties have suggested the holding of national workshops involving the three conventions' focal points in order to facilitate further the implementation of joint work programmes.

  39. ...Action Programmes to Combat Desertification... • Programmes outline long-term strategies and are formulated with the active participation of local communities. • These are essential for providing ownership and continuity for long-term programming. • The participatory process enables governments to coordinate and administer their resources more effectively while addressing the underlying socio-economic causes of desertification. • These approaches pay particular attention to preventive measures and encourage a sense of commitment to sustainable practices by the very people who most depend upon the land. • The programmes should be sufficiently flexible to accommodate new initiatives and local adaptations as circumstances change. • In many instances, the strengthening of the capacities of key actors at the local level has proved successful in identifying and addressing challenges linked to decision making for natural resources management. • The lack of a strong civil society presence in other affected states, however, continues to be a drawback in ensuring people's participation in the mainstream policy formulation and implementation process.

  40. ...Action Programmes to Combat Desertification... • NAPs also specify the practical steps and measures to be taken as well as the commitments made by national governments to provide an "enabling environment". • Specific measures to improve the economic environment could include creating financial instruments suited to local needs or the introduction of drought-resistant crops. • Other measures could include promoting research activities, drought contingency plans, and improved early warning systems. • National governments, for their part, can make commitments to remove obstacles and provide support by enacting new laws or strengthening existing legislation and adopting policies that encourage sustainable development, such as the replacement of fuelwood by other energy sources. • Part of the national budget must be clearly earmarked for efforts to combat desertification and drought according to national conditions and capabilities, but the NAPs are also expected to mobilise substantial financial resources from external sources. • Lack of predictable programme resources and funding has slowed and impeded the implementation of NAPs. • As Parties are now moving from the phase of programme preparation to that of implementation, the establishment of a country-driven mechanism to mobilise international support to the NAP in affected country Parties is urgently called for.

  41. ...Action Programmes to Combat Desertification... • Subregional and regional action programmes (SRAPs and RAPs) can help to harmonise and strengthen national programmes. • These are designed through consultations among the affected countries of each region (such as Africa) and sub-region (such as West Africa). • In addition to boosting the efficiency of national programmes, SRAPs and RAPs can promote joint programmes for the sustainable management of shared rivers and other cross-boundary ecosystems. • The thematic programme networks which often constitute the main elements of RAPs generate spin-off effects on activities taking place at the national level, such as water management, agroforestry and monitoring, and forge each country's scientific and technical capacities. • They may help in disseminating the knowledge of appropriate technologies and good practices. As at March 2002, 7 subregional and 3 regional action programmes had been launched. .

  42. ...Action Programmes to Combat Desertification... • A comprehensive assessment conducted by the Parties in 2000 and 2001 emphasized the possibility of duplicating best practices and successes. • - Successful programme activities and outcomes identified were, inter alia, contribution to a more integrated approach linking national development frameworks and drylands conservation, the strengthening of relationships between governments and local communities, especially in larger countries, the decentralised involvement of stakeholders and natural resources end users in the development process for a variety of programmes beyond the Convention, aided by consultative mechanisms at the regional and local levels, the establishment of national information systems on desertification to enhance information flow between all parties involved, and private entrepreneurship, social mobilisation and the application of appropriate technologies such as drip irrigation, soil conditioning, hydroponic crop production and ecotourism projects.

  43. ...Action Programmes to Combat Desertification • The Parties identified the integration of sustainable development policies into economic policies as a challenge to be overcome. • They highlighted the urgent need for of inter-ministerial cooperation and for the mainstreaming of action programmes into development strategies in order to address the problem in a comprehensive manner and to avoid duplication. • Given that the NAPs cut across many development sectors such as agriculture, forestry and water management, the NAPs have, at times, encouraged inter-ministerial cooperation and focused attention on inappropriate land tenure or certain trade practices not conducive to sustainable land use. • Furthermore, Parties called for the insertion of Convention-related measures into bilateral and multilateral negotiations.

  44. Combating Desertification in Latin America and the Caribbean... • Although better known for their rain forests, Latin America and the Caribbean are actually about one-quarter desert and drylands (20,533,000 km²). • The deserts of Latin America's Pacific coast stretch from southern Ecuador along the entire Peruvian shoreline and well into northern Chile. • Further inland, lying at 3,000-4,500 meters in altitude, the high, dry plains (Altiplano) of the Andean mountains cover large areas of Peru, Bolivia, Chile, and Argentina. • To the east of the Andes, an extensive arid region extends from the Chaco's northern reaches in Paraguay to Patagonia in southern Argentina. • Northeast Brazil contains semi-arid zones dominated by tropical savannah. • Most of Mexico is arid and semi-arid, especially in the north. • The Caribbean states of the Dominican Republic, Cuba, Haiti and Jamaica, amongst others, also contain arid zones; erosion and water shortages are noticeably intensifying in many East Caribbean islands.

  45. ...Combating Desertification in Latin America and the Caribbean... • Poverty and pressure on land resources are causing land degradation in many of these dry areas. • With 465 million inhabitants, Latin America and the Caribbean contain some 110 million people living below the poverty line. • The Convention to Combat Desertification has strong political support. All countries in the region have already joined the Convention. • Non-governmental organisations (NGOs) have organised their efforts through the International network of NGOs, RIOD (Réseau Internationale d'Organisations Non Gouvernementales sur la Désertification). • This network has four subregional focal points and one regional focal point. While RIOD's contribution is important, more needs to be done to attract NGO participation at the national, subregional, and regional levels.

  46. ...Combating Desertification in Latin America and the Caribbean... • The Regional Annex for Latin America and the Caribbean strongly emphasizes the need for sustainable development. • Unsustainable practices include excessive irrigation and inappropriate agricultural practices, inappropriate use of soil, fertilisers and pesticides, overgrazing, and intensive exploitation of forests. • When combined with frequent droughts and forest fires, these practices almost inevitably lead to land degradation. • The resulting sharp drop in the biological productivity of ecosystems in turn reduces the economic productivity of agricultural livestock and forestry. • National Action Programmes (NAPs) have been formulated in several countries. • Many of the countries that have joined the Convention are preparing National Awareness Seminars to encourage widespread participation by communities, NGOs, and other stakeholders in the development and implementation of NAPs. • These plans will also benefit from the region's strong scientific resources. Much remains to be done, however, and institutional and technical capacity-building remains essential for further progress.