  |
 |
 |
 |
Soils Home
About Us
Soil Survey
Soil Use
Soil Education
Photo Gallery
Technical References
Partnerships
Contact Us
|
   |
|
|
2nd International Conference on Land Degradation
Khon Kaen, Thailand Conference Report
C. Anecksamphant, C. Charoenchamratcheep, Published by: Table of Contents
Opening AddressesOpening Address of H.E. Pongpol Adireksarn Mr. Chairman, Ladies and Gentlemen: First of all, I like to welcome you all, particularly the foreign guests, to Thailand and to the beautiful city of Khon Kean. I would also like to extend a special welcome to two of our distinguished guests. First Dr. Winfried Blum, Secretary General of the International Union of Soil Science. We will be working closely with Dr. Blum in the next few years to organize the 17th World Congress of Soil Science. Dr. Blum, we aim to make the Congress the best of its kind and we rely on you to help us in this major event of the next Century. Secondly, our old friend Dr. Hari Eswaran, Chairman of the Working Group on Land Degradation and Desertification. Dr. Hari is a very close friend of all Thai soil scientists. He has been helping us for more than two decades and he is almost a Thai himself. We like to thank you for bringing this Conference to Thailand and your continued support. I hope our guests will have some time to obtain a glimpse of this part of Thailand. Khon Kean is still a small city but vibrant and growing in importance. We have a University here and the Department of Land Development has a regional office. It is the hub of the major activities of the Northeast. Ladies and gentlemen, we have made tremendous progress in this century. Even for a small country like Thailand, our agriculture has made great progress, which has resulted in the export of several crops. Other sectors of society have also improved and the general quality of life for most Thais is much better today than a few decades ago. However, with this progress and affluence, we have also created problems. Our population is increasing and our ability to feed and clothe the people is constantly being challenged. There are factors such as global climate change and land degradation, which may have negative effects on the productivity gains in agriculture. We, perhaps like many other countries, have wishfully believed that these environmental problems are not of sufficient importance in Thailand to invest in research and development funds. We have hesitated to ratify the Desertification Treaty. However, studies by our Department of Land Development is showing that large areas in Thailand are subject to degradation and that about 75% of the land area is vulnerable to desertification. I am sure that you all know that land degradation is like a slow cancer invading the human body. In the past, we only addressed the cancer when we fell sick; usually this was too late. Similarly, land degradation also slowly reduces the productivity of the land. The farmers are aware of this but they correct it by applying more fertilizers and trying to improve the management. I am told that the advances in biotechnology that resulted in high-yielding cultivars are slowly being negated by land degradation. Land degradation is not only a productivity issue but also an environment issue. Water quality and quantity is increasingly becoming an important problem in Thailand and in other countries. Even if we have the land, without water, the human civilization will be hurt. So addressing land degradation and desertification is not only good for agriculture but also for the environment and consequently the general quality of life of the people. So, ladies and gentlemen, we need to support Ambassador Diallo and Dr. Hari in their work. But we also need help from the IUSS and CCD to address these problems in a rational way. We need methods to monitor desertification, we need early warning indicators that will signal problems before they happen, we need to rally our society as a whole and create the necessary awareness to meet the challenges, and we need to use the advances in information technology to address these and other problems. Based on the findings of this Conference and support from international organizations, my Ministry of Agriculture will launch a proactive program. Our Department of Land Development has a good record of assistance in conservation and land resource assessment. They will now have to move into the area of monitoring the land resources so that we will know the state of the Nation's land resources at any time in the future. I challenge the IUSS and CCD to provide us with the tools to implement this ambitious program which will have benefits in all countries of the world. The world of the next Century must be a better place for our children and us. By working together we can make this happen. With that thought, I hereby declare this Conference open. Address of Mr. Sompong Theerawong Your Excellency PONGPOL ADIREKSARN, Minister of Agriculture and Cooperatives, distinguished guests, ladies and gentlemen: In June 1996, the 1st International Conference on Land Degradation was organized in Adana, Turkey through the initiative of Dr. Hari Eswaran and the International Society of Soil Science. I attended this meeting out of curiosity and to learn more about the impacts of land degradation and desertification particularly on the rural poor. When Dr. Hari asked me if we would like to host the 2nd Conference, I agreed for two reasons:
In my career as a soil conservationist and later as Director General of the Department of Land Development, I was convinced that we were doing a good job with respect to addressing conservation and productivity issues. However, I was always unhappy that we were unable to predict degradation. In fact, we were trying to put a lock on the stable door after the cow was stolen. The staff at DLD have in general a good idea where degradation is taking place in Thailand but we have not measured it and we do not have an idea of the rate of degradation. We also do not have a clear understanding of the relationship between land degradation and land management. So all of us have talked about degradation in the past, implementing a program to assess, monitor, and address land degradation is a new challenge not only in Thailand but also in most countries of the world. One of the weaknesses of many countries such as ours is that we do not have a tradition of developing databases. In this modern age, he who has the best database is the king. We need databases that show not only spatial variability but also that show temporal variability. We still have to learn the power of information technology and to put this technology to work for us in combating desertification. In hosting this Conference, we are hoping to resolve some of these issues so that we can work towards solving these problems. I am sure that the papers, posters and discussions of the next few days will generate new ideas and bring us closer to the evasive question of sustainability. Thank you, ladies and gentlemen. Address of Mr. Sima Morakul Your Excellency PONGPOL ADIREKSARN, Minister of Agriculture and Cooperatives, distinguished guests, ladies and gentlemen: It is indeed a pleasure for the Department of Land Development to host this 2nd International Conference on Land Degradation. I am sort of a 'freshie' Director General as I only assumed this position a few months ago. However, I have been with DLD for more than twenty years working in the area of soil and water conservation. Our job is to preserve and protect the nation's land resources. Our job is also to help our farmers to improve their production and to ensure that our people receive a continuous supply of high quality food. This commitment of the Government of the Kingdom of Thailand is not new but dates back to our former Kings. In the last decade, particularly with the United Nation's Conference in 1992 at Rio on "Environment and Development" several old concerns were emphasized and new paradigms were declared. Sometimes, due to all the new declarations by the UN and other international organizations, we are lost or have difficulties in responding to these new initiatives. Unlike the western world, we cannot divert development funds overnight or even have the capacity to address the new initiatives. In this respect, we have been slow in responding to the global initiatives but this does not mean that we do not care or we do not consider the issues important. This Conference on Land Degradation is important to us in DLD, particularly when we are starting to address the questions of degradation, desertification, and impacts of climate change. As you will hear later during the Conference, Thailand has its own share of land resource stresses. Many of these are natural but accelerated by human activities on the land. Some have been specifically created through mismanagement. Recently, we made a preliminary assessment. About 30% of the Kingdom is steepland and though we would prefer to have these under forest, shifting cultivation continues particularly in the northern part of the country. Another 30% of Thai soils that are sandy or gravelly with laterite gravel and these have a very low water holding capacity. They also have a low nutrient status and so even with irrigation, the productivity is low. Close to 4,000 km2 of land is affected by salinity, an equal area with acid sulfate soils, and a large area suffers from seasonal moisture stress. We estimate that about 386 thousand km2 or 75% of land is vulnerable to desertification. Water erosion affects about 66%, physical deterioration about 24%, chemical degradation about 7% and biological degradation impacts about 4% of the land. Our conservation technology is able to contain some of these degradation processes but we still have much work to do to become truly sustainable. We have the capacity to combat desertification but we need your help in terms of concepts, techniques, and approaches. I hope that this Conference will provide us with some guidelines that others around the world and we can use. Thank you, ladies and gentlemen. Address of Dr. Hari Eswaran Your Excellency PONGPOL ADIREKSARN, Minister of Agriculture and Cooperatives, distinguished guests, ladies and gentlemen: In exactly 335 days the year will end and we will be at the beginning of a new Century. We will probably begin the new millennium with the usual stories of conflicts between countries, food shortages and surpluses, the rich getting richer and the poor poorer, and of course the Y2K. Internet gloomsites talk about Armageddon or end of the world (May 2000). Many serious people worry about the Y2K, which can cause all chip-based technology to crash. Is there a Y2K in nature that will cause desertification to be wiped out, environmental problems to disappear, and convert the world to one big garden of Eden. Probably not and that is why we are having this 2nd International Conference on Land Degradation. In the last decade I have become committed to addressing degradation. Once, when travelling with a bunch of soil scientists, specialists from many countries, at each field stop I asked the same question: is this land degraded? What are the processes? At what rate is degradation taking place? For each question, I received six different answers from the five persons. It dawned on me then that though we talk a lot of things about degradation, we really did not understand the processes, we did not know how to recognize it in the field, and we had no clue about the rate of degradation. This was the reason for establishing the Working Group on Land Degradation and Desertification and organizing these Conferences. There are indirect evidences of degradation and despite the absence of reliable databases we have some estimates, at least for global dimensions. These suggest that it is a global issue that affects the livelihood of many people particularly of the poor in developing countries. Our estimates for Africa suggest that about 500 million people in Africa will be impacted and for the world this number may approach 2 billion. It is surprising that many countries have yet to develop national strategic plans to address the issue of land degradation and desertification. Part of the reason is that in the absence of good data. There is not the realization of the negative impacts and the savings that could result if the problems are addressed in a timely manner. The few studies indicate that the productivity of some lands has declined by 50% due to soil erosion and desertification. Yield reduction in Africa due to past soil erosion may range from 2 to 40%, with a mean loss of 8% for the continent. In south Asia, annual loss in productivity is estimated at 36 million tons of cereal equivalent valued at $5,400 million by water erosion, and $1,800 million due to wind erosion. It is estimated that total annual cost of erosion from agriculture in the USA is about $44 billion per year, about $100 per acre of cropland and pasture. On a global scale the annual loss of 75 billion tons of soil costs the world about $400 billion per year, or more than $70 per person per year. There is another dimension that we must understand. There is only about 3% of the global land surface that can be considered as prime or Class I land and this is not to be found in the tropics. There is another 8% land that belongs to Class II and III. This 11% land must feed the 5.9 billion people today and the 9 billion expected in the year 2020. Our data shows that about 33% of the global land surface are subject to desertification. This is about 42 million km2 and affecting more than 2 billion people. We are hoping that this Conference will help to address some of these issues and bring us closer to addressing the challenges. We would like to progress specifically in the following areas:
Countries must develop strategies to combat desertification. Components of a national strategy to address land degradation and desertification include:
Mr. Chairman, we are privileged to be here in Thailand. We are sure to have an interesting and productive meeting and we hope we will live up to the expectations of persons and organizations that have supported this meeting financially or otherwise. Finally, I like to thank the Minister of Agriculture, The Director General of DLD and the President of the Soil and Water Conservation Society of Thailand for their interest and support. Recommendations of the 2nd International Conference on Land DegradationThe degradation of the land resource base is rapidly emerging as an agricultural and environmental concern of major proportions. Its importance transcends the deterioration of the land per se, particularly as it impacts several critical issues of our time: food security, diminishing quality and quantity of water resources, loss of biodiversity, and global climate change. The decline in the land resource base, in important areas of developing countries, will significantly increase the challenge to feed a growing population from a diminishing land area of declining quality, resulting in food insecurity, reduced agricultural income, and slower economic growth. The use of fragile ecosystems by resource poor farmers, the continuing conversion of forests to agriculture, the systematic loss of water storage capacity of soils and in reservoirs through siltation, the systematic loss of biodiversity require monitoring and attention. Further, problems associated with the increasing urbanization including the conversion of quality agricultural lands are issues to be dealt with in the debate on sustainable land management. It is imperative, therefore, that concerted action at the local, national and global level is taken in partnership with farmers and land users to maintain and enhance land quality. Investments in land quality are an essential component to meet a wide range of environmental, economic and welfare goals as we move into the 21st Century. RecommendationsIn this context, the participants of the 2nd International Conference on Land Degradation deliberating on the theme of "Meeting the Challenges of Land Degradation in the 21st Century" recommend that:
Report of the ConferenceIn response to a call for a concerted action on land degradation and desertification by the United Nations Conference on Environment and Development at Rio de Janeiro, Brazil, in 1992, the International Union of Soil Science (IUSS) established the Working Group on Land Degradation and Desertification (WGLDD). The charge of WGLDD is to help develop the 'science of land degradation' and rally the international scientific community to develop acceptable terms and definitions, concepts and methods, and frameworks and thresholds for countries and institutions to adopt common procedures in the assessment and monitoring of land degradation. The first International Conference was held in Adana, Turkey and attended by 250 participants from 25 countries, mainly from the Mediterranean region. In this second Conference, a similar number of persons from 30 countries assembled at Khon Kaen, Thailand. The Conference theme was "Meeting the challenges of land degradation in the 21st Century". With the establishment of the United Nations Convention to Combat Desertification (CCD), the Conference hoped to address some of the issues confronting CCD and provide suggestions, recommendations, and potential sources of expertise for CCD to respond to its mandate. Eight themes were developed and for each theme a specialist was invited to present a 'state-of-the-art' paper. Information is excerpted from these papers and discussions to compile this report. The Proceedings of the Conference, to be published later, provide the original texts. Dimensions of Land Degradation and DesertificationLand degradation, declines in land quality due to natural processes and anthropic activities, is a major global issue for the 20th century and will remain high on the international agenda even for the 21st century. The importance of land degradation among global issues is enhanced because of its impact on world's food security and environment quality. The latter comprises important concerns related to eutrophication of surface water, contamination of ground water, and emissions of trace gases (CO2, CH4, N2O, NOx) from terrestrial/aquatic ecosystems to the atmosphere. Land degradation can also be considered in terms of the loss of actual or potential productivity or utility as a result of natural or anthropic factors. Land degradation, is the decline in land quality or reduction in its productivity and environmental regulatory capacity. In the context of productivity, land degradation results from a mismatch between land quality and land use. Land degradation processes, mechanisms that set-in-motion the degradation trends, include physical, chemical and biological processes. Important among physical processes are decline in soil structure leading to crusting, compaction, erosion, desertification, anaerobiosis, environmental pollution, and unsustainable use of natural resources. Significant chemical processes include acidification and leaching, salinization, and decrease in cation retention capacity and fertility depletion. Biological processes include reduction in total and biomass carbon, and decline in land biodiversity. Soil structure is the important property that effects all three degradation processes. Factors effecting land degradation are biophysical environments that determine the kind of degradation processes, e.g. erosion, salinization etc. These include land quality as affected by its intrinsic properties, climate, terrain and landscape position, and climax vegetation and biodiversity especially the soil biodiversity. Causes of land degradation are the agents that determine the rate of degradation. These are biophysical (land use and land management, including deforestation and tillage methods), socioeconomic (e.g. land tenure, marketing, institutional support, income and human health), and political (e.g. incentives, political stability) forces that influence the effectiveness of processes and factors of land degradation. Land degradation is a biophysical process driven by socioeconomic and political causes. High population density is not necessarily related to land degradation. What the population does to itself and to the land that it depends on determine the extent of land degradation. People can be a major asset in reversing the degradation trend. However, subsistence agriculture, poverty and illiteracy are important causes of land and environmental degradation. People must be healthy and politically and economically motivated to care for the land. Lands, depending on their inherent characteristics and climatic conditions, range from highly resistant or stable to extremely sensitive and fragile. Fragility, extreme sensitivity to degradation processes, may refer to the whole land, a degradation process (e.g. erosion) or a property (e.g. soil structure). Stable or resistant lands do not necessarily resist change. They are in a stable steady state condition with the new environment. Fragile lands degrade to a new steady state under stress, and the altered state mat be unable to support plant growth and to perform environmental regulatory functions. Information on the economic impact of land degradation by different processes on a global scale is only available for some localities. In Canada, for example, on-farm effects of land degradation were estimated to range from $700 to $915 million in 1984. Economic impact of land degradation is extremely severe in densely populated South Asia, and sub-Saharan Africa. Soil compaction is a worldwide problem, especially with adoption of mechanized agriculture. Severe compaction has caused yield reductions of 25 to 50% in some regions of Europe and North America, and 40 to 90% in those of West Africa. In Ohio, reductions in crop yields are 25% in maize, 20% in soybeans, and 30% in oats over a 7 year period. On-farm losses due to land compaction in the United States alone have been estimated at $1.2 billion yr-1. Accelerated soil erosion is another principal land degradation process. Similar to compaction, few attempts have been made to assess the global economic impact of erosion. On plot and field scales, erosion can cause yield reductions of 30 to 90% in some root-restrictive shallow lands of West Africa. Yield reductions of 20 to 40% have been measured for row crops in Ohio and elsewhere in the Midwest USA. In the Andean region of Colombia, workers from the University of Hohenheim, Germany, have observed severe losses due to accelerated erosion on some lands. On a global scale, the productivity of some lands in Africa has declined by 50% due to soil erosion and desertification. Yield reduction in Africa due to past soil erosion may range from 2 to 40%, with a mean loss of 8.2% for the continent. If accelerated erosion continues unabated, yield reductions by the year 2020 may be 16.5%. Annual reduction in total production for 1989 due to accelerated erosion was 8.2 million mega grammes for cereals, 9.2 million mega grammes for roots and tubers, and 0.6 million mega grammes for pulses. There are also serious (20%) productivity losses due to erosion in Asia, especially in India, China, Iran, Israel, Jordan, Lebanon, Nepal and Pakistan. In south Asia, annual loss in productivity is estimated at 36 million tons of cereal with an equivalent valued of $5,400 million by water erosion, and $1,800 million due to wind erosion. It is estimated that total annual cost of erosion from agriculture in the USA is about $44 billion yr-1, about $100 acre-1 of cropland and pasture. On a global scale the annual loss of 75 billion tons of soil costs (at $3 ton-1 of soil for nutrients and $2 ton-1 of soil, for water) the world about $400 billion yr-1, or more than $70 per person yr-1. Nutrient depletion is another principal process of land degradation with severe economic impact at a global scale, especially in sub-Saharan Africa. Dutch workers have estimated nutrient balance for 38 countries in sub-Saharan Africa. Annual soil fertility depletion rates were estimated at 22 Kg N, 3 Kg P, and 15 Kg K ha-1. Soil erosion in Zimbabwe results in an annual loss of N and P alone totaled $1.5 billion. In south Asia, annual economic loss is estimated at $600 million for nutrient loss by erosion, and $1,200 million due to soil fertility depletion. Salt affected lands occupy an estimated 950 million ha of land in arid and semi-arid regions, nearly 33% of the potentially arable land area of the world. Productivity of irrigated lands is severely threatened by build up of salt in the root zone. In south Asia, annual economic loss is estimated at $500 million from waterlogging, and $1,500 million due to salinization. Potential and actual economic impact globally is not known. Soil acidity and resultant toxicity due to high concentrations of Al and Mn in the root zone, is a serious problem in sub-humid and humid regions. Once again, the economic impact on a global scale is not known. It is in the context of the global economic and environmental impacts of land degradation and numerous functions of value to humans that the land degradation, desertification, and resilience concepts are relevant. They are also important in developing technologies for reversing land degradation trends and mitigating the greenhouse effect through land and ecosystem restoration. Land resources are essentially non-renewable. Hence, it is necessary to adopt a positive approach to sustainable management of these finite resources. Despite the voluminous literature, land degradation remains a debatable issue. There are two distinct schools regarding the severity and impact of land degradation. One school believes that it is a serious global threat posing a major challenge to the human race with regards to its adverse impact on biomass productivity and the environment quality. Ecologists, soil scientists and agronomists primarily support this argument. The second school, comprising primarily economists, believes that if land degradation were a severe issue, why have the market forces not taken it care of? Supporters of the second school argue that land managers (e.g., farmers) have vested interest in their land and will not let it degrade to the point that it is detrimental to their profit margin. Research and Development IssuesLand degradation as occurring in various forms continues to pose a most serious challenge for the very survival, well-being and future of the whole humankind. Complicated by great uncertainty in climate change, unforeseen impact of human activities and inner interactions among the landscape system components, land degradation per se has become a phenomenon which combines various environmental controls. Consequently, rehabilitation of the degraded land must be comprehensive in nature, encompassing physical, biological and agricultural remedial measures whose implementation inevitably needs to be in line with what is now called the sustainable development principle. Yet, a lack of adequate quantitative as well as qualitative information about the causes, processes and patterns of land degradation, a deficiency of truly applicable rehabilitation techniques, programmes and strategies, and a perpetual ambiguity of the meaning of sustainability in relation to different spatial, temporal and human scales still defy efforts to solve the degradation malaise in many parts of the world. To meet the land degradation challenge in the twenty-first century, a series of changes must be made to the way how the land is viewed, what strategy should be adopted for rehabilitation efforts and what aims should be served by the rehabilitation endeavors. In particular, several key needs are of vital importance:
Environment, Biodiversity, and Food Security IssuesLand degradation has potentially severe implications for food security, rural livelihoods, and environmental attributes such as biological diversity. Not only does degradation diminish the quality of the remaining land resources but also it undermines the life-support functions of the soil for both human welfare and the health of the natural environment. The challenge of African agriculture is not only of enhancing production to meet the increased food demands of the expanding population, but also the judicious use of soils so that their productivity is sustained in the foreseeable future. Continent-wise 55 % of land area in Africa is unsuitable for agriculture and 11 % of land area has high quality soils which can effectively be managed to sustain more than double its current population. These soils are spread among many countries making it difficult to develop a continent-level strategy to equitably help all countries. Africa has more than 8 million km2 of land with rainfed crop potential, however, much of it has not been used for this purpose. This potential land reserve needs to be carefully evaluated so that rational policies can be developed for their exploitation. The studies of vulnerability to desertification clearly show:
The challenge of enhancing the productivity of well endowed lands and reducing the pressures on the fragile ecosystems is the solution to putting Africa on the path to sustainability development. With appropriate capital infusion and support services, the efficiency of resource-poor farmers of Africa can be raised and the seeds to another Green Revolution sown. The current population of Asia is about 3.2 billion and is expected to grow to 4.5 billion by the year 2025. Analysis clearly shows that most Asian countries will not be able to feed their projected populations without irreversibly degrading its land resources, even with high levels of management inputs. The overall prospects for food security in Asia are not encouraging. Only a few countries will be able to feed their growing populations without increasing land management input levels markedly. And most countries of the region lack the capital resources to make the financial investments required to increase land productivity. Nevertheless, the three largest and most populous countries of Asia, China, India and Indonesia, should be able to meet minimal food requirements, provided the level of management technology is increased. It appears unlikely, however, that countries like Afghanistan and Pakistan will be able to produce sufficient food now or in the future. Although the same is true for industrialized countries like Japan, Singapore and Taiwan, they can rely on non-agricultural industry, commerce and servicing functions to earn the money to import food. There are several adverse aspects precipitated by the current and future situation of local and global environmental consequence. First, farmers in the poorer countries will be forced to eke out a living by exploiting fragile land resources, which often results in irreversible degradation and permanent loss of biodiversity. Second, the relative scarcity of prime agricultural land in Asia and the resulting imperative to preserve these areas for food production and optimize the land use of the remaining areas precludes more land for agricultural expansion. This implies that soil scientists must expand their horizons and explore all functions of the soil and land resource in support of food security and quality of life. Third, although there is nothing inherently wrong with importing food from elsewhere, this leads to the appropriation of natural resources in other countries, which may not be a sustainable procedure. To confront the problem of food security in Asia, massive infusions of capital are needed to support, inter alia,
Asia will continue to be a tension zone for food security and depend on imports to feed its growing population, but there is hope that these requirements can be met from external sources. At a recent meeting on "Land Resources: At the Edge of the Malthusian Precipice," a group of experts concluded that "if all (of the world's) resources are harnessed to minimize soil degradation, sufficient food to feed the population in 2020 can be produced, and probably sufficient for a few billion more". Although continued population growth will inevitably have disagreeable consequences, it is thus unlikely that the Four Horsemen of the Apocalypse will pay a call in the foreseeable future. Should Malthusian scenarios emerge, they are less likely to be caused by global environmental collapse rather than by humankind's perennial inability to conduct its political affairs wisely. Although it is not possible to be specific about the climate changes that will take place on an intra-regional basis, it is likely that most regions of the world will be affected in some way or other and will require an ongoing level of new understanding and readjustment. It is well known that climate is a major factor in soil erosion. Some areas of the world, e.g. Southern Asia, are predicted to have increased temperatures combined with increased rainfall. Such areas may become more prone to water erosion depending on the existing land use at the time. In many other areas, global warming is likely to lead to higher evaporation rates and drier soils. Cultivation of such soils or other changes in ecosystem could make them more prone to erosion both by water and wind. The USLE and EPIC erosion models have been used in the USA to predict changes in erosion rates with different climate change scenarios. It is found that average rill and sheet erosion rates could increase by up to 22% depending on the climate change scenario. Given a 2°C rise in temperature, wind erosion could increase by 15-18 percent while water erosion decreased by 3-5%. In most areas of the world, there will be a significant risk of increased erosion under the present climate change predictions. Climate-related factors such as increased drought could lead to an increase in the vulnerability of some land to desertification and to escalation of the desertification process. Because arid and semi-arid land ecosystems have little ability to buffer the effects of climate variability relative to most other terrestrial ecosystems, they are particularly vulnerable to climate change and may be the first ecosystems to be affected by global environmental change. By coupling a vegetation model to the Hadley Centre Global climate model , it has been predicted that there will be a decline in tropical forests and grasslands from 2050 onwards and increasing development of deserts in Africa, India and parts of South America. In those areas affected by warmer, more droughty conditions, reversing the effects of desertification is not always possible and becomes more difficult in drier climates and where there are shallower soils. In those regions in which the climate is due to become warmer and more arid, e.g. northern and southern parts of Africa, northern part of South America, India and Southern Europe, salinization and alkalization are likely to increase because transpiration and capillary rise will be enhanced. Climate is the most critical factor in determining the sustainability of agricultural systems, with hot, dry areas the most difficult in which to achieve sustainability. Much attention is being directed towards maintaining the multi-functionality of soils but this will become more difficult in warmer, drier climates. Climate change will almost certainly change a region's soils with respect to their carrying capacity, their resilience, sensitivity and susceptibility to stress, and the potential reversibility of damage to them. It is important that the impact of climate change on soils is considered in parallel with impacts caused by unsustainable land management. The two often interact leading to a greater cumulative effect on soils than would be predicted from a summation of their effects. Land Management, Land Laws, and Policy IssuesEnvironmental legislation and policies concerning the use of agricultural land have existed since early this century. Land degradation continues to expand worldwide suggesting that the existing environmental laws and policies have not been effective to prevent land degradation. Recently, international forums and conventions have provided impetus for some nations to prepare new environmental law, environmental policies and strategies, including the preparation of law and policy specifically aimed at the control and management of land degradation. The main type of legislation and policy material aimed at the control of soil and land degradation is 'soil conservation law. Many such laws focus on land utilization rather than on land conservation. However, in many cases, the effectiveness of legislation was overshadowed by agricultural production price support schemes for domestic and export needs, land settlement and land development schemes, rather than for ecological objectives. It is becoming evident that a wide range of programs, policies, educational initiatives and national and local laws are necessary to successfully achieve ecologically sustainable land management. The principal global environmental treaties, conventions, and strategies to achieve ecologically sustainable development, combat desertification, manage forests, control the effects of climate change, and to manage biodiversity, are beginning to be used to re-assess and reinvigorate domestic and international environmental laws and policies. Results of recent environmental law and policy reform, particularly in developing countries, indicates that nations are committed to initiate and implement but lack guidance and information. There is an urgent need to assemble experts in this field and develop appropriate protocols and guidelines. Tools for Identification, Assessment, and MonitoringSatellite Remote Sensing (SRS) and Geographic Information Systems (GIS) are widely used tools in various fields including land cover assessment and land use change. These are also studies used in land degradation studies, such as erosion prediction and nutrient depletion. However, their uses at the national scale in Asian context to-date have not gained popularity due to several reasons. The use of remote sensing data provides timely and reasonably reliable information for large area monitoring supported by sufficient ground data. Otherwise, large scale monitoring needs a considerable amount of human resources and time if generated through field survey only. As socioeconomic information is important in the process of land degradation monitoring, one of the reasons for potential use of these technologies is the increasing realization of geo-referencing of such data. Besides, the tool also allows the delineation and geographical distribution of different types of land degradation, which is not successfully achieved at the national scale until now. Global Positioning System (GPS) is another emerging tool that is very useful in land resources studies. The unique feature of remote sensing, compared to other tools, such as GIS, thematic cartography, or statistics, is that it can be used to collect the data for baseline inventory or regular monitoring purposes which can be integrated with other tools for further analysis. The present remote sensing technologies can be broadly categorized into V/NIR and Microwave remote sensing. V/NIR sensing has received wider application acceptance compared to Microwave sensing. This is due to microwave remote sensing, being, weather independent, and lacking in adequate methodologies for specific application. There are number of currently operating and proposed satellite remote sensing systems, such as Landsat, MOSS, SPOT, NOAA, ERS, RASARSAT, JERS, MODIS, each of the sensors having different spectral and radiometric characteristics. Their potential uses depend upon the biophysical variables under study. The majority of remotely sensed data collected for earth resource applications is the result of satellite on-board sensors that record electromagnetic energy. Changes in the amount and properties of the electromagnetic radiation becomes, upon detection, a valuable source of data for interpreting important properties of the phenomena with which they interact. Since monitoring of land degradation is largely concerned with mapping the productivity status of land resources under a given socioeconomic setup, such areas can be easily identified, delineated and monitored with repetitive data collection using remote sensing techniques. Subsequently, it can be modeled using the data from other sources to understand the relationship between the degradation status and associated factors and actors. Such information is valuable to develop the strategies required by specific degraded areas. Satellite remote sensing, however is superior in many aspects such as cost effectiveness for large area monitoring, geo-referencing and near real-time monitoring of land degradation. The vegetation status of certain area reflects strong correlation with productivity status of the land, thus degradation status. As vegetation has a strong spectral response in NIR band, construction of vegetation indices is a usual practice to estimate the vegetation component of an area, thus assessing degradation status of the land on the basis of vegetation health. In the case of tropical wet-climates, one of the major shortcomings experienced in the use of V/NIR data is the problem of cloud cover affecting the data. Cloud free data are available only during the dry season, and such data contain little information on vegetation spectral responses. Among others are the temporal resolutions of most of the high-resolution sensors, which might not be efficient in reliably capturing critical greening of vegetation. There are also other considerations to be taken into account, such as the trade-off between spatial resolution and swath coverage, selection of appropriate analytical technique, timely data availability and delivery while using the remotely-sensed data for land degradation studies. The main purpose of land degradation monitoring is to formulate conservation strategies to protect land resources for long-term sustainability. Experiences in some parts of the world have shown that without understanding the basic processes and values of degradation and how the communities are the part of it? How do they respond? The monitoring process simply does not carry much value. In general, Remote sensing is a very useful and efficient tool to in performing important steps during land degradation studies, such as identification, assessment and monitoring. However success depends upon several factors including natural status of the area, selection of appropriate remote sensing data and analysis techniques. As in situ information collection is essential in the process of remote sensing application for calibration purposes, integration of other tools, like GIS and GPS, is essential to improve the accuracy of the result than by using the remote sensing alone. Soil erosion by water is the principal cause of land degradation, and it is a major constraint to agricultural development in many countries. Soil and water conservation measures have to be adopted not only to reduce on-site soil, water and nutrient losses, but also to diminish negative downstream effects, such as flooding and the silting up of reservoirs. It is however extremely difficult to evaluate such soil and water conservation measures economically, since neither their effects nor their beneficiaries can be easily detected. For the appraisal of soil and water conservation projects much attention needs therefore to be paid to the identification of target groups and other actors and to an assessment of all major on-site and downstream effects of the measures. This requires both socioeconomic research and hydrological and erosion research, and requires a thorough integration of physical and biological aspects with economic considerations. In the impact assessment use can be made of water and nutrient balances and yield response functions, which can be incorporated in spreadsheet modules and multiple spreadsheet models. In the economic evaluation of projects use can be made of both cost-benefit analysis (CBA) and multi-criteria analysis (MCA). The efficiency of the projects can be conveniently assessed with CBA, when the effects can be quantified and valued. Whereas MCA can be used to assess scores on non-monetary attributes of the various evaluation criteria, and can also show how conflicting objectives of different actors affect these scores. Mitigation Technologies and Implementation ProgramsReversing global land degradation is about better and simpler technologies, better national policies, and much more. But ultimately it is about rural people and their institutions. The greatest prospect for reversing land degradation in the next century is the evolution of real farmer-led community institutions that take charge and transform the way research and extension in land management are done. Broad-based evidence for this is emerging. Examples of locally-led processes in natural resource conservation suggest two successful streams:
Four examples of locally created groups that have had remarkable success in attacking land degradation problems in different parts of the world were presented. These include the mwethya self-help work groups in the Machakos District in Kenya that released a huge voluntary effort that constructed large areas of terraces to control soil erosion over the years. Farmers' clubs that are a vehicle for widespread diffusion of soil and water conservation practices in southern Zimbabwe; the explosive development of 4,500 farmer-led community Land Care groups in Australia and include about a third of the country's farmers is a national success story. A similar Land Care movement that evolved in the uplands of the southern Philippines focussing on the spread of natural vegetative strips, farm forestry, and other agroforestry practices is another example. These farmer-led institutions are independent self-governing entities that may receive training and material support from outside, but they determine their agenda and implement it through their own efforts. There are also important success stories emanating from the second stream of conservation institutions, that are locally-led but created and actively guided by the public sector. Examples include the Catchment Conservation Committees in Kenya, the Conservation Districts movement of over 3,000 self-governing districts in North America that have been supporting the spread of conservation practices among their members for decades; and the emergence of municipal natural resource management planning and implementation in the Philippines. The two streams of institutional approaches are not incompatible with each other. They may be integrated in the same area in mutually supportive ways, as seen in the confluence of Land Care and Conservation Districts in Western Australia. These experiences are from both the temperate and tropical worlds. They indicate that community institutions are a vast underutilized resource for planning and implementing resource conservation at the global level. Outside support is often critical for leadership training and modest material support. Local labor and resources combined with modest external assistance through cost-sharing, foster sustainable development. And linkages to external sources of information and support are fundamental for long term sustainability of these institutions. A community-based strategy needs mechanisms to facilitate these links. Networks of farmer-led community groups will be needed within each country. Likewise, more networking between countries will also be crucial. These networks will accelerate the realization of the power of farmer-fed community institutions to reverse land degradation on a global scale during the 21st century. Efforts to reverse natural resource degradation through international funded projects and many times due to an inability to develop the rapport with local communities, appear to have mixed results. Literally hundreds of thousands of projects have been implemented, although their impacts have been disappointing. There is no dearth of mitigating technologies that keep erosion in check and maintain soil fertility for sustainable agricultural production. Recently recognition has grown that farmers do not benefit as much from adopting soil conserving practices and technologies as previously assumed. Economic analyses have indicated that while society may gain from a reduction in negative externalities, farmers have to pay the price. Many projects and programs attempt to bridge the conflict between the private and society's interests by enforcing either strict land use and management regulations or by offering subsidies to those farmers willing to farm their land according to mutually agreed conservation principles. For project intervention purposes, the two contrasting approaches also have been combined to the "stick and carrot" approach, where the carrot acts as a direct incentive stimulating the adoption of specific recommendations. The use of direct incentives has limited potentials, often with only short-term and negligible impacts. What most of us perceive, as appropriate incentives are in fact inadequate measures for bringing about change. This change is what we should direct our attention at instead of focusing on making alternative technologies more profitable or palatable. The objective is to broaden the perspective of incentives. It specifically proposes the move away from using narrowly defined "carrots" designed to raise the attractiveness of mitigating technologies. The consensus is growing that certain sectoral and macro-economic policies (subsidies, guaranteed prices, and income assistance programs), that affect especially farm incomes, are instrumental in contributing to the problem of land degradation. Just as natural resource degradation is policy-induced, its reversal also needs to be triggered and supported by policies. Instead of searching for more appropriate incentives, it is far more effective to accept that land degradation is caused by market failures and to find the disincentives that prevent farm households from adapting their livelihood strategies according to the requirement of sustainable land use. With respect to limitations of direct incentives, the importance of differentiating between subsidies and compensation must be emphasized. Various studies indicate that the concept of "carrots" as incentives is much too limiting. Instead a whole jar of "mixed pickles" addresses the obstacles to resource conservation more effectively. Among those that should receive more consideration are sectoral and macro-economic variable incentives such as prices, and fiscal and monetary measures, as well as enabling incentives such as market development or the decentralization and devolution of natural resource management (cf. IFAD, 1998). As long as the framework conditions are not conducive to conservation, direct incentives will remain drops in the ocean and many incentives such as free input and food for work will continue to be misused as bribes for boosting the performance of projects. ConclusionWhereas land degradation remains a serious global threat, the science involved is still composed both myths and facts. The debate is perpetuated by several factors that have caused confusion, misunderstanding and misinterpretation of the available information. Important among these is:
Key aspects of a reform strategy to achieve a goal of sustainable land management, includes:
The Conference concluded that land degradation is not likely to be a serious threat to international food trade between now and 2020, due to the global capacity for substitution, and the dominance of temperate producers. But it could have significant effects on national agricultural supply (14-17% reduction by some estimates) in many countries, and on global, and particularly national prices (17-30%) increases by some estimates). The greatest impact of land degradation will be the dampened economic growth effects of lower farm incomes in the irrigated, high quality rainfed and densely-populated marginal lands, due to lost soil productivity. The major economic threat will be in those countries and sub-regions, which depend upon agriculture as the "engine of economic growth." The greatest threats to nutrition and food consumption by poor farmers in 2020 will be in the densely-populated marginal lands of sub-Saharan Africa, and to a lesser extent South and Southeast Asia. Total agricultural land loss predicted by 2020 does not pose a major threat to global wealth in soil assets, however for countries with a limited land base, conserving farmland quality is a strategic long-term food security issue. The greatest problems of soil degradation for food security in developing countries in 2020 will be found in the densely populated marginal lands, which require mobilization of long-term investment and appropriate technology development. Second in importance will be degradation of irrigated lands through salinization and waterlogging. In high quality rainfed lands, farmers are likely to respond actively to degradation with improved land management, assuming general support for agricultural development. Agricultural land quality and preservation in urban and peri-urban areas will be much more problematic. Land degradation in lightly populated marginal lands is unlikely to pose major economic (as distinct from environmental) costs beyond producers themselves. The current challenge we face is to:
Working Group On Land Degradation and Desertification of the International Union of Soil SciencesCore Committee
Members of the Recommendation Committee
Second International Conference on Land DegradationKhon Kaen, Thailand Organizers
Co-sponsors
Conference ProgramSunday, 24/1/991400-2000 Registration Monday, 25/1/990700 Registration (cont.) 0900 Opening Ceremony (MC: Wanarat Thothong) Opening of the Poster Session Opening Session - Keynote Address 1100 Land degradation and desertification: an overview Hari Eswaran and Rattan Lal 1200 Lunch Technical Session I: Tools for Identification, Assessment and Monitoring 1330 Tools for identification, assessment and monitoring of land degradation Apisit Eiumnoh 1400 A three-way methodology for assessing land resources, their problems and possible solutions at small scales Roel Oldeman and Godert W.J. van Lynden 1430 Assessment of land degradation in the Philippines: a case study in Isabela Province Perfecto P. Evangelista, Cleotilde M. Nicolas and Toshiaki Ohkura 1450 Landscape-scale changes in soil properties between 1967 and 1995 in Bangladesh Md. Mohsin Ali and Toshiyuki Wakatsuki Refreshments and poster viewing Session I. (cont.) Chairman: Fritz Penning de Vries Rapporteur: Anna Tengberg 1540 Sediment yield from upland areas in relation to surface microtopography M.J.M. Römkens, K. Helming and S.N. Prasad 1600 Spatial natural resource monitoring in the Mpumalanga Province of South Africa Konrad J. Wessels and Dirk J. Pretorius 1620 Soil degradation under different land use systems in a laterite landscape of Peninsular India G. Byju and Thomas Varghese 1640 Application of low-cost remotely sensed images for ecosystem monitoring Edward L. Webb, Ma. Arlene Evangelista and Julie A. Robinson 1700 A practical method for assessing the soil erosion and water pollution hazard associated with logging in New South Wales, Australia Neil A. Abraham, P.J. Fogarty and S.J. Beaman Adjourn 1800-2000 Welcome Reception Tuesday, 26/1/99Technical Session II: Impacts of Land Degradation Chairman: Rogelio N. Concepcion Rapporteur: Chapika Sangkapitux 0830 Future risks and consequences of soil degradation in developing countries Sara Scherr 0900 Socioeconomic consequences of land degradation in the South American Gran Chaco Paul Huszar 0930 The economic appraisal of soil and water conservation measures Jan de Graaff 0950 Economic implications of land degradation under a large size irrigation project in India B.V. Chinnappa Reddy, Honniah and Lalith Achoth Refreshments and poster viewing Session II. (cont.) Chairman: Ruben Puentes Rapporteur: Rannveig Ólafsdóttir 1030 Highlands in East Africa: unstable slopes, unstable environments? Lars-Ove Westerberg and Carl Christiansson 1100 Ecological problem and its trend diagnosis of land utilization in Guangdong Province Peng Zhiliang, Zu Lianfeng, Zhang Chao and Li Sui Huai 1120 Land degradation problems in Hungary Adam Kertesz 1140 Assessing the impact of land degradation on rice production in Northeast Thailand Masao Ohnishi, Takeshi Horie, Koki Homma, Satoshi Kondo, Hiroshi Takano, Tastuya Inamura, Chemnean Thongthai and Supapoj Nopporn 1200 Soil acidification under Stylosanthes seed production systems in Northeast Thailand and Northern Australia: a potential constraint to long-term sustainability Andrew N. Noble, Sawaeng Ruaysoongnern, Ian Willett and Brian Palmer Lunch Technical Session III: Land Management, Land Use Law and Policy Issues Chairman: David Sanders Rapporteur: Madusha Chandrasekera 1330 Policy and law for management of land degradation: a global view Ian Hannam 1400 Policies for sustainable land management Winfried E.H. Blum 1430 Agroecological management of degrading coastal dunes: a major land resource area in Southern Anatolia Oguz Dinc, Selim Kapur, Erhan Akca, Cengiz Yetis, Yilmaz Bal, Suat Senol and Ural Dinc 1450 Impacts of soil conservation: ASIALAND Management of Sloping Land Network Ty Phommasack and Adisak Sajjapongse Refreshments and poster viewing Session III. (cont.) Chairman: Ian Hannam Rapporteur: Worapong Waramit 1540 The status of land degradation in Vietnam Thai Phien, Nguyen Van Bo and Nguyen Tu Siem 1600 Degraded soils in Sri Lanka Ananda N. Jayakody 1620 Land degradation in Bangladesh Md. Mustafizur Rahman 1640 Land degradation and re-establishment strategies in Thailand Pisoot Vijarnsorn 1700 Laws and policies to counteract land degradation in the Philippines: agricultural perspectives Rogelio N. Concepcion and Gina P. Nilo 1720 Adjourn Wednesday Mid-conference tour 27/1/99 Tour I: Industry tour Tour II: Rural development tour Thursday, 28/1/99Technical Session IV: Mitigating Technologies and Implementation Programme Chairman: Lamond Graham Rapporteur: Tim Brasuell 0830 Replacing carrots with mixed pickles: the role of incentives in soil conservation Thomas Enters 0900 Land degradation in the Hindu Kush-Himalayas - ICIMOD's response Richard Allen 0930 Status of land degradation and attempts to control in ASOCON countries Frank J. Dent 0950 Soil management in tea lands by adopting "Sloping Agricultural Land Technology (SALT)" P.B. Ekanayake 1010 Sylvi-pasture system: an appropriate technology to rehabilitate degraded
grassland Djoko Santoso Status of land degradation and preventive measures
undertaken in Malaysia Jusop Shamshuddin Refreshments and poster viewing Technical Session V: Research and Development Issues Chairman: Antonio Ramalho Rapporteur: Boonna Anandana 1120 Land degradation, information needs and challenges to research Fritz Penning de Vries 1150 Futuristic approaches in soil resources and land degradation inventories and their application Mariappan Velayutham 1220 Lunch Session V (cont.) Chairman: Adisak Sajjapongse Rapporteur: Christl Bühmann 1330 Soil erosion and appropriate techniques for improving Map Bon soil with artificial removal of topsoil in LWCC Project Sakda Sukviboon, Dechar Sumrit, Sutham Paladsongkram and Mitsuo Fukuda 1350 Sustainable rehabilitation of degraded volcanic ash soils in the semi-arid highlands of Mexico U. Fechter-Escamilla and G. Werner 1410 Sediment production on roads and other land use surfaces in Northern Thailand: preliminary results of field rainfall simulation Alan D. Ziegler, Ross A. Sutherland and Thomas W. Giambelluca 1430 Refreshments and poster viewing Technical Session VI: Environment, Biodiversity and Food Security Issues Chairman: Nguyen Van Bo Rapporteur: Nitayaporn Tonmanee 1500 Land quality and food security in Asia Fred H. Beinroth, Hari Eswaran and Paul F. Reich 1530 Land degradation, food security and biodiversity: examining an old problem in a new way Anna Tengberg and Michael Stocking 1600 Meeting the international challenges of land degradation and biodiversity conservation Anders Jonas Rupp-Desrosiers 1620 Food production and environmental degradation E.M. Bridges and L.R. Oldeman 1640 Strategies for waste minimization in agriculture and natural resources - the prospect for the 21st Century Liu-Hsiung Chuang 1700 Prevention of land degradation under use of saline and brackish water for irrigation Jingsong Yang, Feng Xue, Deming Chen and Dongshun Li Adjourn 1830-2130 Conference Banquet Friday, 29/1/99Technical Session VII: Desertification and Climate Change Chairman: Hari Eswaran Rapporteur: Georg R. Hennemann 0830 The potential impact of climate change on land degradation and desertification Peter Bullock 0900 Desertification and global climate change - Little Ice Age desertification in Iceland Ulf Héllden and Rannveig Ólafsdóttir 0930 Land and civilization Anthony S.R. Juo and L.P. Wilding 0950 Land degradation indicators in the arid environment Shabbir A. Shahid and Samira A.S. Omar 1010 Interpretations of environmental change and diversity: a critical approach to indications of degradation Annika C. Dahlberg 1030 Refreshments and poster viewing Technical Session VIII: General Considerations on Land Degradation and Conservation Chairman: Hidenori Wada Rapporteur: Bubpha Topark-Ngarm 1100 Farmer-led community institutions: key to reversing land degradation in the 21st Century Dennis P. Garrity 1130 Land degradation and rehabilitation in the Twenty-First Century: meet the challenge, make the change Y.Q. Li 1150 Understanding land degradation and the problems of addressing it in Southern New South Wales, Australia Ian Packer 1210 Lunch Session VIII (cont.) Chairman: Frank J. Dent Rapporteur: Gitte Rubaek 1330 Farmer adoption of soil conservation practices in developing countries: economic and institutional considerations Sushil Pandey 1400 Farmers' attitudes towards soil conservation in mountainous regions of Thailand and Vietnam Andreas Neef and Chapika Sangkapitux 1420 Soil conservation between counselling, missionary and unmet need Wulf Raubold 1440 Plenary Session Chairman: Roel Oldeman Rapporteur: Ananda N. Jayakody 1540 Refreshments Closing Session (Announcer: Charoen Charoenchamratcheep) Report of the Secretary of the International Working Group of Land 1700 Degradation and Desertification of the IUSS Vote of thanks, Chairman of the International Working Group on Land Degradation and Desertification of the IUSS Closing address, President of the Soil and Water Conservation Society of Thailand Saturday, 30/1/990800 Departure for the post-conference excursion to Nakorn Ratchasima Province and the Eastern part of the country, to end in Bangkok in the evening of Tuesday, 02 February 1999 at around 1800-1900. Poster PresentationsSection 1. Identification, causes and impacts
Section 2. Management, prevention and amelioration
Organizing Committee
3rd International Conference On Land Degradation and Desertification Contact: |
|
|
|
Back to Top