SUSTAINABLE AGRICULTURAL AND RURAL DWELOPMENT OF THE LOESS PLATEAU：PLANNIG OR THE FUTURE

Executive summary

Background

Agriculture started on the Loess Plateau 7-8,000 years ago and hence can be considered one of the important birthplaces of Chinese and World agriculture. The climate is generally favourable to agriculture, though too dry in some areas. Most of the soils are very deep and suitable for good crop growth if well managed. These favourable natural resources permitted a productive agriculture that allowed the Zhu, Qin and Han Dynasties to flourish. Since then, however, there has been progressive environmental degradation. Deforestation from the Qin dynasty onwards degraded the land and exposed the fragile soil to water erosion. Increasing population pressure from 500 B.C. and particularly during the past 500 years of almost exponential population growth, led to extensive clearance and cultivation of highly erodible slopelands, and to some of the most serious soil erosion in the world. Collectively, these two detrimental changes have contributed to progressive loss of the soil organic matter vital for sustainable agriculture, to poverty amongst rural people on the Plateau, and to both frequent floods and seasonal breaks in the flow of the Yellow River and its tributaries, causing loss of life and economic disruption respectively in Provinces downstream of the Plateau.The environmental degradation of the Loess Plateau is therefore an issue for whole China and not just for Shaanxi and Shanxi.

This situation can be reversed or substantially improved. The environmental degradation and poverty can be overcome in two principal ways. Agricultural R&D in China and elsewhere in the world has provided the technological means to reverse much of the soil erosion and restore soil organic matter levels. Wise development of the huge energy resources of the Loess Plateau can provide the capital needed for the creation of dynamic local economies. It can generate rural and urban employment so that farmer families on the more marginal lands can progressively leave agriculture to gain a better living in the industrial or service sectors, and allow such land to revert to grassland, forest or scrubland in an environmentally sound way.

The Sustainable Agricultural Working Group (SAWG) has considered the issues surrounding the sustainable development of the Loess Plateau, and examined the opportunities for sound action. The most important activities were an extensive field visit to the Loess Plateau in mid May 1999, and an International Workshop on Land Use and Sustainable Development of the Loess Plateau, held in Beijing at the end of May 1999. The former gave SAWG the opportunity of examining directly both the problems and some of the possible solutions and discussing these with senior provincial and local officials, scientists and farmers. The latter widened the involvement of SETC, MOA and other state officials and additional international and Chinese scientists. This report concentrates on the main issues and opportunities identified by these two activities and on SAWG's recommendations arising from them.

Issues and Recommendations for a Long-term Sustainable Development

Ⅰ. Conservation based land and water management 

Issues:The soils of the Loess Plateau are inherently low in organic matter and lay content. This makes Loess soils relatively easy to cultivate, but very usceptible to the serious wind and water erosion. These weaknesses are made worse by the widespread use of intensive tillage practices. Therefore it is essential that these tillage pressures are lowered and soils be protected by vegetation cover or crop residue. Every effort should be made to enhance the soil organic matter levels of these soils to improve their stability, ecology and productivity. Such measures will also help to reduce water evaporation and compensate for the lack of rainfall.

Recommendations: Greater priority should be given to on going efforts to transfer Chinese and overseas R&D and experience on more sustainable tillage/cropping practices to Loess Plateau farmers, which do not leave loess soils without cover and vulnerable to erosion. A demonstration project should be mounted to train farmers in reduced tillage and stubble retention methods on their own land and then use these farmers and farms in a pilot farmer trains farmer programme for the promotion of the wider uptake of these methods.

Every effort should be made to stop the cultivation and grazing of steep slopes with special emphasis on those measures given in the following recommendations. These include the use of confined feeding systems for livestock, simple reseeding techniques, grass strips instead of machine made terraces, replanting of slope lands with grasses and shrubs to sequester carbon, and creating nonagricultural jobs for those currently farming fragile slope lands. It is suggested the use of various types of ground cover plants in apple orchards instead of the bare soil. The benefits of the cover crops include biological N fixation, reduced soil erosion, lower pest attacks, higher soil organic matter and better soil moisture holding capacity. The balanced fertiliser use for major users like wheat, with less N and more P and K is also important. The gains here are both global and national. Balanced fertiliser reduces nitrous oxide emissions, reduces farmer's costs and can lower soil erosion. Ⅱ. Integrated management of the Yellow River Basin 

Issues: Erosion control in the Loess Plateau is central to the State Ecocons truction Programme to reduce the major impact that soil sediments from this region have upon the flow and course of the downstream portions of the Yellow River. The enormous efforts being made in the middle and upper reaches of the Basin to control erosion through revegetation and engineering solutions are making good progress but are not sufficient to prevent continued choking of the main channels with eroded soil, and major flooding the lower reaches and provinces. The current rate of water extractions are causing the main lower channels of the Yellow River to run dry six years out of ten, compared with three years in ten around before 1990, and the situation is projected to get worse.

The current Committee of Water Conservancy of Yellow River does not have the necessary authority and resources to achieve equitable water sharing between provinces, realistic water pricing and cost sharing, and to implement a holistic natural resource management strategy. Consequently, for example, the upper and middle reaches provinces are extracting too much water for less efficient irrigation, and causing severe water shortages in the lower reaches. Moreover, the regional problem in Yellow River Basin is not only water conservancy, but water conservancy, agriculture, forestry and etc.

Recommendation: It is necessary to enforce the integrated management of Yellow River Basin, to reconstruct the Committee of Water Conservancy of Yellow River and change its name to Committee of Integrated Management of Yellow River. The Committee is entitled to bring State agencies together with all 11 provinces that are responsible for, and lie within, the Basin. It could be headed by a senior leader of the State Council to provide the necessary authority for implementation of its strategies. It could draw upon the experience of River Basin Management Authorities in other countries that have similar challenges in managing complex issues of water and land management across a range of jurisdictions. It should provide the coordination, sharing of costs and benefits and regulatory monitoring. Ⅲ. The role of livestock in optimising resource use 

Issues: Improvement of Loess Plateau farmer incomes is dependent on raising their productivity and diversifying their products. They could respond more to the growing local markets for livestock products. At the moment they do not make full use of the potential for raising livestock on underutilised cropresidues and forage resources. Ruminant animals can be an economic and ecologically sound way of using crop byproducts and forage as the livestock feed base.

Recommendations: The agricultural structure should be changed and expansion of plant sector should be constrained. More should be done to develop ruminant animal husbandry among farmers of the Loess Plateau, primarily using confined feeding systems to reduce the risk of negative impacts of grazing on steep slopes, Emphasis should be on local breeds of beef cattle, sheep and goats.

Advanced technologies can be very effective for restoring degraded land to provide both grazing land and forage, but they are generally too costly for widespread use. It is therefore recommended that R&D institutions and local officials do more to develop and disseminate "low technology" solutions to overcome soil erosion and the loss of vegetation. In particular, there are local forages, which are or could be as good as some of the imported plant germplasm favoured by scientists. There are also simple native plant reseeding techniques that could achieve vegetation restoration at very low cost.

Ⅳ. Improving the client and market focus of agricultural R&D and extension services

Issues: The State Government has conducted long-term research and demonstration projects on soil conservation and agricultural development on Loess Plateau since the 1950s. During the period from the sixth five year plan to the ninth five year plan the State Government successfully enhanced R&D and demonstration activities resulting in improved technologies, new models of agricultural development, and more trained researchers. However, the potentials of these competent scientists and wellequipped institutions have not been fully utilised. For example, the current State Eco-construction Programme has been conducting R&D in some areas of the Loess Plateau, but few academic institutions have been involved, which is a serious under utilisation of national scientific resources. Furthermore, it is difficult to ensure that the programmes are ecologically and economic sustainable. There seems to be a tendency to continue research programmes longer than necessary and at times some reluctance to undertake R&D on techniques which will require major changes in local farming practices. There are a number of appropriate technologies available in other countries that could make an important contribution to the restoration of the Loess Plateau. Some individual scientists have responded to these opportunities, but there appears to be no national or provincial strategy to exploit these opportunities.

Recommendations: Research institutions and scientists should be encouraged to support the State Ecoconstruction Programme and undertake innovative applied research on sustainable soil and crop management technologies. National and provincial authorities could take a more active role in promoting the adoption of appropriate technologies from other countries even though these may have low acceptance among farmers at the time, such as the reduced tillage technologies mentioned above.

Ⅴ. Market development, market competition and comparative advantage 

Issues: The move to a market economy in China and economic globalisation provides the Loess Plateau with good opportunities for development, but also presents the region with greater risks and uncertainties regarding agricultural diversification. The everincreasing market (price) fluctuations faced by farmer's demands that thorough market analysis is completed before promoting new industrial or product development. This analysis must determine whether there are viable longterm markets for new products. It is clear from the SAWG field survey in May 1999 that the local policymakers have not paid enough attentions to these issues. Loess Plateau farmers have successfully adopted fruit tree cultivation, but they are now finding it difficult to sell their apples profitably. The problem seems likely to get worse as production is still expanding on the Loess Plateau and elsewhere in China. It is critically important that there is a thorough analysis of the real market opportunities before making massive investments in new production capacity, and every effort is made to avoid farmers being discouraged in the future from adopting new innovations. Farmers have production experience but little formal education and limited skills in marketing, financial management and human resource management. These difficulties regarding the development of new crops are particularly important given that China currently does not have international comparative advantage for a number of bulk crops, and policy makers have not adequately addressed this fact. For example, the protection rate for wheat and corn (that is, the amount by which local prices exceed world market prices) has been up to 20-30% in recent years.

Recommendations: Further economic development should be based on the optimal utilisation of resources and comparative advantages. Policymakers should assess thoroughly the comparative advantage of local products in national and international markets before encouraging farmers to change their cropping systems. Greater emphasis should be given to (a) assessing the longterm comparative advantage of the Loess Plateau for fruit production; (b) providing more training to farm advisors on marketing aspects; (c) supporting farmers by a better information system about present and potential markets for different crops and their prices and helping them to improve their financial management skills; (d) fruit processing units should be established to widen market opportunities. A concerted effort should be made by the Chinese government to widen market opportunities. A concerted effort should be made by the Chinese government to improve the skills of extension and farm service personnel with emphasis on marketing and financial management.

Ⅵ. Getting the best return from investment. 

Issues: Machine made wide terraces have been very successful in controlling soil erosion and raising farm incomes such that the non-labour construction costs of c.700 RMB/mu can be paid back within about 3 years. However, the total costs are higher because of labour, road construction and other supporting activities, so other erosion control measures like grass strips can be more costeffective in the longterm and more sustainable because of their contribution to higher soil organic matter content and productivity. Moreover, (a) some of the terraces now being built may be too small in the longerterm for profitable intensive farming, and (b) the area of slopeland needing soil erosion control is much greater than that for which funding of machine made terraces can be found. It is unlikely that more than a small proportion of all the needy farmers and vulnerable slopes on the Loess Plateau can be protected from soil erosion by the creation of these machinemade wide terraces.

Recommendation: The choice between alternative soil conservation techniques should be based on a more comprehensive analysis of shortterm economic costs and longerterm productivity benefits. Alternative ways of terracing should be devised, which integrate where possible other objectives, such as infrastructure, energy and rural development. For example, through the construction of small to large scale man made plains.

Ⅶ. Improving land property right and rural credit services 

Issues: Unclear or insecure land property rights and inadequate credit services on the Loess Plateau and elsewhere in China have become important constraints to farmer's investment in land improvements and the rapid development of the rural areas. Secure property rights are a vital catalyst for sound natural resource management and economic development. Farmers have to own the land or be confident that they will have user rights long enough to receive the full benefits of any investments they make in it. Different land property systems exert different impacts on productivity and resource degradation. The redistribution of farmland can have beneficial impacts on resource utilisation, farmer income parity, soil quality and institutional system developments (for example, the land rent market). A survey on the Loess Plateau has highlighted inadequacies in current rural credit services with many farmers in Shanxi Province, for example, being unable to obtain loans. Interestingly, 50% of the farmers wished to get loans for non-agricultural industries.

Recommendations: Land property rights on the Loess Plateau should be clarified to encourage farmers to increase investment on land, and to improve the rational use and conservation of natural resources.Rural credit services should be improved, possibly modelled on the current small scale loan project which has been very effective in raising rural household economic development in less favoured areas.

Ⅷ. The Role of the Loess Plateau in national and global development

Issues: National food security policy and its implementation via provincial and local government responsibility for grain supplies with restrictions on internal grain trading may have a number of adverse affects. Farmer's incomes and local development opportunities could be reduced. They may result in unnecessary grain production, and prevent comparative advantage determining where grain supplies can be developed most efficiently and achieving the most appropriate mix of products and production options. They could adversely affect sustainable agricultural development by forcing more agricultural production increasingly onto more marginal lands. The Loess Plateau has vast energy resources which are progressively being developed but the main economic and employment benefits are gained by other regions of China in the form of cheap energy and the raw materials for petrochemical industries which in turn support a wide range of manufacturing companies. Thus the Loess Plateau, for example, receives much of the environmental damage from coal mining, but none of the employment benefits of the downstream industries that could provide higher incomes than from the farming of the marginal slope lands.

This energy generation makes a significant contribution to China's carbon dioxide emissions. The Loess Plateau through many of the above recommendations, for example, the promotion of reduced tillage, grass strips, and cheaper vegetation restoration techniques greatly contribute to China's international obligations. Such actions could sequester large amounts of carbon dioxide as soil carbon. Thus, the Loess Plateau could sequester over 4 million tons of carbon annually from arable land, and possibly double this amount from restored slope lands re-planted with grasses and shrubs.

Recommendations: Planning of the Loess Plateau development should be more closely integrated with national planning so that (a) national and regional grain policies do not have adverse effects on environmental sustainability; (b) people of the region receive a more equitable share of the benefits of the energy resources they provide to China, and (c) so that it can make a major contribution to meeting China's international obligations for climate change mitigation.

1. Introduction 

The exploitation of the Loess Plateau's natural resources has played a very important role in the evolution of Chinese civilization, and in social and economic development. As one of the cradles of Chinese culture ancient civilizations flourished on the Loess Plateau more than 2,000 years ago. Thus it has been an important national center of political and economic development for a long time. More recently, it has become an important production base for China's energy and chemical industries. However, there have been growing concerns about the Plateau's unique environmental landscape and a series of ecological problems caused by serious soil erosion. The Loess Plateau ecosystem is very fragile, and has been under increasing stress since 500 B.C. The expansion of the cultivated area because of population pressure has caused serious damage to the ecosystem. Consequently, the Loess Plateau has become one of the most serious soil erosion areas in the world. The process of ecological degradation and land resource destruction has hampered the development of the regional economy. It has suffered from a vicious circle of "the more people have to cultivate, the more poor; and the more poor, the more cultivation takes place", which has seriously restricted poverty alleviation and welfare improvement. Moreover, the soil erosion by water and wind has caused sedimentation of the riverbed in the lower reaches of the Yellow River and its tributaries. The levees along the rivers have had to be raised, but this puts the lower reaches at greater flood risk, and adversely affects lives, properties and economic development on the Huanghuaihai Plain. Government at all levels has therefore given more attention to the eco-construction of the Loess Plateau. Conditions have been particularly favourable since 1970, but progress has been slow, and much remains to be done. At the end of the twentieth century and the dawn of the next one, China's economic capacity for change has increased steadily and the state macroeconomy is undergoing important strategic structural alternations. Now is an appropriate time to reconsider the development issues of the Loess Plateau, and to overcome the ecological degradation problems and other constraints to long-term development.The Loess Plateau is therefore the key target region of the CCICED Sustainable Agriculture Working Group (SAWG) in 1999. The SAWG members visited more than ten municipals (counties) in Shanxi Province and Inner Mongolia Autonomous Region of the Loess Plateau during May 15-23,1999. They conducted field surveys, listened to reports, and discussed problems and opportunities with local officials, scientific researchers, and farmers. On the 25-26 May, 1999, the SAWG organised in Beijing the International Workshop of Land Use and Sustainable Development of the Loess Plateau in Northwest China. Invited experts and officials from government agencies, research institutions and international organisations, together with the SAWG member gave presentations to the workshop. SAWG then held a two day meeting to discuss the recommendations for this annual report, and review the latest development on the demonstration projects in Inner Mongolia Autonomous Region proposed in 1998. It decided to select the Mid-Yangtze and red soil areas of South China as the target regions for the field survey in 2000, where the focus would be the environmental problems of intensive crop production. This report was written on the basis of field survey and the workshop. 2 Natural and eco-social environment 

2.1 Natural Environments 

2.1.1 Geographical coexistence of the Loess Plateau and the Yellow River Basin

The Yellow River is China's second largest river and well known for its high silt concentration. The Loess Plateau is located on the upper and middle reaches of the Yellow River. Its serious soil erosion is the main reason for the river's high silt concentration.

The Yellow River originates on the northeastern Qinhai Tibet Plateau, and runs through the nine provinces of Qinhai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi, Henan and Shandong, and finally flows into the Buohai Sea.

The Loess Plateau is bounded in the south by the Qinling Mountain, in the east by the Taihang Mountain, in the north by the Yinshan Mountain, and in the west by the Riyue and Helan Mountains. It covers an area of 580,000km2, of which 430,000km2 suffer from eroision. The average annual stream runoff of the Yellow River is 58 billion m3 with a sediment load of 1.6 billion tons per year. The runoff from the upper reaches accounts for 54% of the discharge, but only 9% of the sediment. Whereas the stream runoff from the middle reaches accounts for 44% of the discharge and 90% of the sediment, which comes mainly from soil erosion on the Loess Plateau.

The natural climate of the Loess Plateau is characterised by the transition from temperate monsoon in the east to arid and semiarid area in the north. In economic terms it is characterised by the transition from the developed east of China to the developing west area.

2.1.2 Geology and geomorphology 

The geo-tectonic system of the Loess Plateau can be divided into two parts along Liupanshan Mountain. In the west, uplift movements are faster than in the east. This leads to a high frequency of earthquakes and gravity erosion such as land slides.

The Loess Plateau was formed during the Quaternary Period by loess deposition. The thickness of the loess profile is about 100-200 meters with maximum of 336 meters. The geomorphology of the Loess Plateau is characterised by four main physical features: loess high plain, loess ridge hills, loess mound hills and various kinds of gullies and valleys. There are also middle and lower rock mountains and hills with altitude of 1000-2000 meters and relative height difference of 100-300 meters. Most of the area has a gully density of 3-5 km/km2，with a maximum of 10 km/km2. The gully area accounts for 30-50% of the total area in hilly region, rising to 60% along the Yellow River. Slopes tend to be very steep, so land with a more than 15 degree slope accounts for 60% of the area. There is a transitional geomorphology of wind erosion and water erosion along the Great Wall.

The active neotectonic movement, the erosion prone landform of gullies and valleys and the steep slope land are the main geological and geomorphologic factors influencing the soil erosion.

2.1.3 Climate and weather 

The prevailing weather pattern for the Loess Plateau is a north monsoon in winter and a south monsoon in the summer. The highest winds usually occur in the spring, with maximum velocities reaching 23 m/s, and often leading to sand storms.

(1) Temperature

The Loess Plateau belongs to the continental monsoon region with annual temperature of 3.6-1 degrees, decreasing from the south to the north and the east to the west. Seasonal differences are large, ranging from 22 degrees in July to 0 and minus 14 in January. The annual solar radiation is high, that is, about 50x108-63x108 J./m2. The frostfree period is 80-100 days in the north, 150-180 days in the middle and 200-240 days in the south.

(2) Precipitation

Annual precipitation on the Loess Plateau ranges from 200 to 700 mm, decreasing from south to north or from the southeast to northwest. It is characterised by low and very variable annual precipitation, large interand intra seasonal differences and concentrated rainstorm leading to serious soil erosion, floods and droughts. Fifty percent of the annual precipitation is concentrated in July and August. The maximum recorded daily precipitation is more than 250 mm. This kind of rainfall often causes severe soil loss. One rainstorm may account for more than 70% of the total annual erosion and 90% of the total erosion amount in the flood season.

2.1.4 Vegetation and soil 

Originally the Loess Plateau is characterised by wide flat landform, few gullies and luxurious vegetation. However, most of the natural vegetation has been destroyed. The forest cover is now only 6.5%. According to investigations on the residual preserved vegetation, there are more than 500 species of grass, 250 species of trees and 3000 other plant species remaining but generally at very low frequencies.

The Loess Plateau can be divided from south to north on the basis of its vegetation into the temperate forest, temperate foreststeppe, temperate steppe, temperate desertsteppe and temperate steppedesert zones. This zonal distribution has been lost by human destruction.

The natural soil profile has also been lost. A few complete soil profiles remain as relics on the flat high plain or on the low part of hilly region. The surface soil on the Loess Plateau is mostly the agricultural soil remaining after the parent layer has been eroded.

2.2 Human Environments 

The Loess Plateau has a long history of agriculture and husbandry. In the year of 608, the population of the Loess Plateau accounted for 25.4‰ of the nation's population (Table 1).[JZ] Table 1 Population of the Loess Plateau in history 

Century(A.D) Population on LoessPlateau(104 persons) Population of wholeCounty(104 persons) Percentage of the LoessPlateau in wholeCountry(%)

2 11285 59595 196

609 11952 46019 254

1102 6503 45324 143

1457-1571 15157 62595 242

1820 29956 353400 84

1840 41002 421267 97

1928 31329 441850 71

1949 36395 541670 87

1982 78113 1004021 78

1985 81392 1058510 77 

With the rapid development of agriculture and husbandry, and increasingly intensive destruction of vegetation, the frequency and magnitude of drought and flood disasters increased in the Yellow River catchment, especially after the fourteenth century (Table 2).

Since the beginning of the nineteenth century, the population on the Loess Plateau has accounted for 7-9% of the nation's population, but with a growth rate higher than the national average rate. In Qinhai, Ningxia and Inner Mongolia, the population growth rate was also higher, but with low literacy rates -25% of the population are illiterate or semi-illiterate, rising to more than 80% for women.

Most of the badly eroded areas of the Loess Plateau are poverty regions. With the vicious conjunction of backward farming practices, and serious soil erosion, the lack of food is the major problem for these regions. In 1985, average grain yields were about 2000 kg production per hectare, 1000 kg lower than the national average. In the most seriously eroded areas, the slope farmland produced less than 500 kg per hectare, and annual per capita incomes were less than 400 RMB yuan.

Table 2 Land use patterns and disasters in the Yellow River basin 

Years Land usepatterns change of vegetation

Floods & droughts dykes broken

number Frequency(/100a) number frequency(/100a)

B.C.1978 husbandry rich forest and grass - - 8 0.4

229-148 transition fromhusb. to agri. destruction of forest 29 13 13 5.5

148-609 husbandry recover ofvegetation 9 1 8 1.2

609-1220 transition frombush. to argi. Destruction offorest and grass 45 5.9 509 6.71

1271-1368 172

1368-1644 great develop.of agriculture Serious destructionof forest and grass 116 21.4 934

1644-1911

1912-1936 103 439.2 

Since the late 1980's central government has made these regions the focus of actions to overcome poverty and improve environmental controls. Transportation systems and mining were developed quickly, and food availability and people's lives have been improved. However, because of the fragile environment and weak economic base, the task of soil and water conservation is still demanding, and drought and flood disasters still threaten the security of the lower reaches of the Yellow River and the sustainable agriculture development.

2.3 Soil Erosion and Its Control 

2.3.1 Regional distribution of soil erosion and its control 

On the basis of bioclimate characteristics and the primary erosion agents, the Loess Plateau can divide from south to north into the forest or forest steppe water erosion region, the steppe water wind erosion region and desert steppe wind erosion region. The water erosion region accounts for 46%, the water wind erosion region for 29% and wind erosion region for 25% respectively. The area with the erosion rate of more than 10,000 tons/km2. a accounts for 8% in the water wind erosion region, and 4% in the water erosion region (Table 3).

Table 3 Area of different soil erosion types of the Loess Plateau

Soil erosion agent and rate of loss(each year) Area(104km2) Percentage of the total area(%)

Wind Erosion 1565 25

Waterwind Erosion 1782 29

＞5，000t/km2·a 1057 17

＞10，000t/km2·a 484 8

Water Erosion 2893 46

＞5，000t/km2·a 1056 17

＞10，000t/km2·a 275 4

Total Area 6240 

The most serious soil erosion occurs in the windwater erosion region, i.e. the three province boundary region of Shaanxi, Shanxi and Inner Mongolia. This region has an annual precipitation of 400 mm with high frequency of rainstorm, wind and sand storm. Soil erosion takes place throughout the year; wind erosion in winter and spring, water erosion in summer and autumn. This region is also the major source of the coarse sand (＞005 mm) in the lower reaches of the Yellow River. Most of the rivers in this region have the sediment load of 15,000—25,000 t/km2·a. The maximum sediment load of 66,400 t/km2·a. and the highest silt concentration of 1,700 kg/m3 occur in this region.

The threeprovince boundary region has been a poverty area because of the poor communications, backward farming practices, slow progress with soil and water conservation and the fragile environment. Since the late 1980's, the development of coal mining (with geological storage of 270 billion tons) has stimulated socioeconomic progress with the expansion of the energy generation industry, transport infrastructure, and city construction. These developments, on the one hand, have speeded up progress on soil and water conservation works, but on the other hand, have caused new environment problems. The development of the mining industry can improve the environment. For example, in the town of Daluta the development of the ShenmoDongsheng mine has led to a 50% decrease in farm land and labour inputs but agriculture production increased three times by increasing inputs of technology and capital investment and income per capita have risen by 4—10 times.

2.3.2 Soil erosion on slops farmland and sustainable agriculture development 

The soil erosion from the large areas of steeply sloping farmland is the main factor shaping the landscape of the Loess Plateau. It is the major constraint to sustainable agriculture development and the primary source of sediment in the Yellow River.

Rapid population growth has led directly destruction of vegetation and accelerated soil erosion. From 1953 to 1984, the population of the Loess Plateau had increased from 32.8 million to 71.6 million. In the Fuxian and Ganquan counties of Yan'an, which have protected areas of natural secondary forest, population increased by up to 44‰ and 65‰ respectively. In the past 30 years, the forest line has receded by 2.4 km per year due to reclamation of the forestland. The slope farmland has extended from gentle slope to steep slope of more than 25 degree, and from hill slope to gully slope. In the Xinzihe watershed (1486.1 km2), sloped farmland accounts for 90% of the total farmland, and the areas with slopes greater than 25 degree account for 50%. In the loess hilly region, soil erosion on slope farmland accounts for 60% of total erosion amount.

The slope farmland of the Loess Plateau suffers from sheet or rill erosion, as well as shallow gully erosion. The latter mainly occurred on the slope farmland with more than is degree, especially on the slope farmland with more than 25 degree. The density of shallow gully may be up to 641 km/km2. Erosion rates on the slope farmland with shallow gully erosion have increased two or three times. The shallow gully erosion is the original type of modern gully erosion. Thus control of shallow gully erosion on the slope farmland with should be given greater attention.

Fifty percent of food production on the Loess Plateau depends on the slope farmland. However, the slope farmland has poor fertility, and is susceptible to drought and flood and consequently suffers from low and unstable grain production. In the loess hilly region, one person cultivates 0.33—1.3 hm2 slope farmland.

The major measures currently in use to control soil erosion on the slope farmland are wide terraces. With food requirement of 200—300 kg/person. a and that one person has 0.13—0.2 hm2 high production farmland (refer to terrace and dam land), to restore the steep slope farmland into forest or grassland. However the progress of building terrace, depending on human labours, was very slow. One person can only build 0.006 hm2 a year. Other measures such as contour planting, ridge planting, intercropping and mulching are only in the experimental or demonstrative stage, and have not been extended to a wider area.

Central government has recently enlarged efforts on soil and water conservation. Also, with the supported of the World Bank and FAO the building of terraces using machines has developed greatly. The rate of building terraces increased by three or five times. The area of terraced land increased by 0.03 hm2/person a year. Grain production on these terraces can be raised by 2—4 times compared with the slope farmland.

China's reforms of the past decade have brought many opportunities to lower poverty and erosion. Soil and water conservation has taken a great step forward. For example, through the development of better connections to the market economy. But many remain to be done to raise awareness of the importance of soil and water conservation on the Loess Plateau, and the difficulties and long duration of its control. The soil erosion situation on large areas of slope farmland has not changed appreciably and the ecoenvironment is still fragile, with limited abilities to prevent or mitigate drought, storm and flood disasters. Thus there is still a long way to go to realise the sustainable agriculture development. R&D is needed to provide satisfactory erosion control methods for the large areas of slopeland which cannot benefit from machine made terracing. Better scientific techniques are needed for the design and planning of terraces to gain the maximum economic benefits from them; for the cheaper construction of terraces; for the maturation of techniques for increasing production of new built terrace; tillage techniques for soil and water conservation on large slope farmland; development models for agro-forestry and agro-husbandry comprehensive system on slopeland.

2.3.3 Vegetation and soil erosion 

The regional distribution of vegetation types shows that 70% of the Loess Plateau would not be eroded or only weakly eroded if human activities had not destroyed the natural vegetation. The data from large experimental plots in Ziwuling shows that once the forestland was reclaimed, soil losses tended to rise from human induce accelerated erosion with the erosion rates increasing by 7,000—8,000 times from tens of tons to 10,000 tons km2·a Even in plots with felled trees but no land clearance, soil erosion was very weak (Table 4)due to the protection of roots and litters. It shows that once the loose loess soil is covered with vegetation, even with grass or leaves, it is possible to reduce appreciably the erosivity of rainfall and water flow.

The river sediment load is 5,000 to 10,000 t/km2 when the forest cover is less than 40%; and less than 500 t/km2 when the forest cover is more than 80% (Table 5). The flood disasters and high river sediments are usually caused by soil an water loss in the mainstreams and tributaries of the Yellow River. It follows that the vegetation cover rate plays a key regulation role regarding disaster events. Thus vegetation reconstruction should be the primary measure for the environmental construction.

Table 4 Comparison of erosion intensity on different

topographic locations and utilisation 

Location Utilisation Period Plotarea(m2) Slopedegree Runoff (m3/km2·a) Erosion(t/km2·a) Times

Plotnumber Slope land

Forestland 1989—1991 9658 32 21526 129 22 5

Reclaimed farmland 1990—1991 11443 34 3233516

970370 22 7

Reclaimed bareland 1990—1991 9952 32 2747950 10324

50 22 6

Gullyslope Land

Forest 1989—1991 2535 3742 148150 1441 28 1

Reclaimed farmland 1990—1991 4065 3841 3910959 1

317935 24 8

Reclaimed bareland 1990—1991 2438 3742 4112398 2

177412 24 2

Slopeland plus gully slopeland

Forest 1989—1991 16648 3238 29601 099 20 4

Felling residual land 1990—1991 22621 3438 4791

048 17 9

Reclaimed bareland 1990—1991 14097 3238 242594 1

528694 24 3 

Table 5 Average values (1960—1984) of vegetation co

ver in watersheds and sediment load

Observing stations Area(km2) Vegetat

oncover(°) Volume of runoff(mm) Sediment load(t/km2·a)

Hongde 4640 0 1289 739767

HongdeQinyang 1577 0 2346 681248

Zichang 913 0 43.35 10585.17

Riule 528 2.1 29.27 7076.44

Ganguyi 5891 13.0 37.17 7844.59

Liujiaxia 7325 18.3 33.19 9976.51

JiaokouheZhangcunyi 12456 39.4 30.56 5869.52

Zhuangtu 25154 43.5 36.77 3320.69

Jiaokouhe 17180 55.5 28.56 2855.99

Banqiao 807 66.0 25.60 2035.89

JiaokouheLiujiahe 9855 82.5 25.12 147.50

Linzheng 1121 94.4 21.18 463.90

Zhangcunyi 4715 97.0 22.23 126.25

LongmenTuguai 197662 41.40 5450.40

ZhuangtuZhangjiashan

HeLongHuaZhuang 667946 61.88 2079.12

Vegetation reconstruction depends on the conversion of steep slope farmland to the forest or grassland. And this conversion depends on the basic farmland construction (terrace fields and dammed land) and on improving grain yields, where good farmland produces 1500—2000 kg/hm2 of grain, and one person has 0.13—0.2hm2 of this land, this conversion can be widely carried out, and vegetation reconstruction can be sustained. In the past four decades vegetation reconstruction by planting trees and grass has been implemented on the Loess Plateau. Around 70% of the total erosion areas is thought to have been replanted, but only 20—30% of the area has benefited fully from it because vegetation reconstruction lacked appropriate scientific technology. Problems also remain regarding strategic planning and investment policy for vegetation reconstruction.

2.3.4 The impact of soil and water conservation on the Yellow

River management and disaster reduction. 

In 1989 government agencies using remote sensing data formerly reported that soil erosion area of the nation was 3,670,000 km2, of which 465,000 km2 lie in the Loess Plateau (water erosion area of 347,000 km2 and wind erosion area of 118,000 km2). By the end of 1989 the total area on the Loess Plateau with erosion controls was 133,700 km2, of which terrace land was 20,900 km2; dam land, 2,800 km2; vegetation construction, 93,000 km2. In addition, there were 600 reservoirs capable of storing millions of cubic meters. These soil and water conservation measures reduced annual sediment in the Yellow River by 0.3 billion tons in 1980's and 1970's, with 90% of this improvement coming from dams and reservoirs, and less 5% from vegetation reconstruction. Is is not clear why vegetation reconstruction area accounted for 70% of the total control area but only 5% of the reduction in sediment. This issue needs further research. The annual sediment load of the Yellow River is commonly given as 1.6 billion tons, but it has been less since 1970s (Table 6). One reason is that dams and reservoirs play a great role in the reduction of sediment. The other reason is that natural precipitation and rainfall intensity tended to be lower. Given that the erosion landscape and eco-environment are not basically unchanged it would appear that the existing controlling measures are not enough to prevent disastrous rainstorms and floods. For example, during the 1970s was successfully expanded and played an important role in reduction of sediment. However, in 1977 an extreme rainstorm between Hekouzheng and Longmen brought 2.44 billion tons of sediment into the Yellow River, and 1 billion tons sediment was deposited in the lower reaches of the Yellow River. This caused Yan'an City to be flooded, and in the Gusanchu River catchment 80% of the reservoirs were destroyed or ruined.

Table 6 The average sediment load of the Yellow River since 1920 

Year series Sediment load(billion tons)

Runoff(108m3) Concentration of sediment(kg/m3)

1920—1929 12 3518 353

1930—1939 18 4425 398

1940—1949 17 4838 354

1950—1959 18 4321 391

1960—1969 17 4330 395

1970—1979 14 3605 375

1970—1984 12 3481 332 

Since 1950 the Yellow River has run safely because great dikes have been constructed along the main stream of the River in it's lower reaches. These dikes have been raised and consolidated three times during this period. A lot of dams and reservoirs have been also constructed. As shown in Table 6, the extreme drought in 1920's resulted in average annual sediment loads of 1.2 billion tons, but in the next four decades, the annual sediment load was continually up to 1.7 billion tons. Extreme rainstorms and floods or extreme floods occur once in about 30—40 years, thus as we step into the 21st century, we must pay attention to the rising risk of such kind of extreme events.

3 Experiences and problems of sustainable development 

The Sustainable Agriculture Working Group conducted a field survey in Northern Shanxi and Inner Mongolia Autonomous Region. Extensive contact and discussions took place with local officials, researchers and farmers. The SAWG's understanding of the whole situation, past experience and present issues of Loess Plateau development benefited greatly from these contacts. The SAWG's assessment is as follows.

3.1 Essentials of Sustainable Development 

The Loess Plateau, especially Northern Shanxi province, is one of the areas in which environment and development are in serious conflict, so greater effort to achieve sustainable development in this area are essential. There are four particular reasons for giving priority to the Plateau.

First, the Loess Plateau is the most serious soil erosion region in China and possibly in the world. The ecosystem of the Loess Plateau is very fragile. Improper exploitation has caused ecological degradation and a series of social, environmental and economic problems such as sedimentation of the riverbed of the Yellow River, the decrease of agricultural productivity and so on. The amount and area of sand and soil erosion in Shanxi province accounts for a large percentage of that on the Loess Plateau, so Shanxi province is the key region for eco-construction on the Plateau and for water and soil conservation in the middle reaches of Yellow River.

Second, the Northern Shanxi region is a key poverty alleviation region in China. Now that some areas are short of water resource, the soil erosion is very serious, infrastructural development is slow, and it will be very difficult to alleviate the poverty of a million people before the year 2000. Furthermore, this region is tending to relapse into a vicious circle of the more people have to cultivate, the more poor, and the more poor, the more cultivation in a situation where too much unsuitable land is already being cultivated.Third, the Northern Shanxi region is rich in energy resources and is the potential production base for very large energy and heavy chemical industries. It is rich in both coal and natural gas, which has strategic implications for national modernisation. On one hand, energy and heavy chemical industry development will probably cause environmental problems, but on the other hand, it will strengthen the financial capacity for ecoconstruction.Finally,the Northern Shanxi region has substantial potential for ecologically appropriate agricultural development in the next century. If integrated development is implemented for natural resources, production facilities, technical innovation and management capability, together with sustainable agricultural development, the Loess Plateau will play an important role in the regional food balance in the next century. This has been testified in Yan'an area.In conclusion, the basic way to solve conflict between environment and development and achieve sustainable development is to integrate more effectively water and soil conservation, agricultural development, energy production base and poverty alleviation.

3.2 Experiences of Land Development and Management

There has been no radical improvement in soil erosion control on a large scale after several decades of efforts to improve land management. Positive effects for regional development and management have been achieved, however, and experiences have been accumulated at the local level, which provide a sound foundation for improving extension and land management at a larger scale: In Yan'an and Yulin, for example, new development guidelines and great changes in water and soil conservation, and ecoconstruction have raised per capita income, agricultural production, and food selfsufficiency. They all show the potential for establishing a positive circle of sustainable development in the future.

3.2.1 Historical experiences 

Before the 1980s the main method of ecological management on the Loess Plateau was the planting of trees and grasses. The objective was simply ecological protection purpose and did not include farmers' food security and welfare. It therefore received little farmer support and progress was very slow.Since 1980s, however, small basin management had been recognised as an efficient approach to soil and water conservation. It was formulated from the experiences in the hilly and gully area of the Loess Plateau. The measures include terracing farmlands, restoring the forest from farmlands with steep slopes of more than 25℃, building embankments for silting the valley plain and storing the water, and so on. Small basin management has three advantages. First, it changes the landscape and controls ecological degradation. Second, it aims to increase agricultural productivity and improve the local farmers' welfare. Third, it reduces the amount of soil loss. Since the integrated small basin management approach combines eco-construction with direct measures to raise farmers' welfare the results have been better. Today, more than one thousand small basins have been selected for improvement. However, it is still difficult to extend these experiences to a larger scale because of the limitations of the small basin management approach when placed in a wider sustainable development context.In 1990s, with the boosting of national power and more attention being given to improving socioeconomic progress in the west of China, the Loess Plateau Region is facing a new opportunity for development. The active national financial policies have led to more funds being invested in the eco-construction of the Loess Plateau. Various ministries and departments have set up a lot of key counties and demonstration regions for water and soil conservation, ecological agriculture and eco-construction in Loess Plateau. International organisations such as World Bank and research institutions have also set up demonstration projects for research and poverty alleviation in order to speed up the regional development. Consequently, the abovementioned measures are fostering integrated management and largescale control of soil erosion is entering a new stage.

3.2.2 Experiences in Yan'an and Yulin regions 

In Yan'an and Yulin areas the relationship between eco-construction and social and economic development has progressed step by step following a thorough examination of the historical experiences and lessons. The objective is to combine farmers' creativity and hard work with science and technology, and not only slowdown the procession of soil erosion and increase the agricultural productivity, and to set a model for regional leading industries to harness ecology for development. The primary lesson from the experience in the Yan'an and Yulin areas is the need to change policy guideline so they combine the exploitation and development of natural resources with sound ecoenvironment measures, productivity improvement, poverty alleviation to find new ways of controlling soil erosion. The three most fundamental changes are:

(1) Laying particular stress on the benefits from integrated approaches to economic, social and ecological concerns. In the past stress had been on ecological benefits and without farmers interests. The integration of economic and eco-lolgical benefits has now mobilised farmer's activity on abandoned hills and barren slopes, which had been considered as a "burden", but are now seen as a source of "wealth" for poverty alleviation.

(2) Switching from an emphasis on management to one combining management with development. In Yan'an, the primary tasks are: vigorously constructing basic croplands and developing different kinds of economic woods and fruits;bringing together water and soil conservation, exploitation of water and land resource, and poverty alleviation and income growth; fell together building of element establishments and integrated exploitation of agriculture, so that the process of economy development has been enhanced.

(3) Moving from a focus on single management tasks to the comprehensive management of small basins. With the former it was difficult to bring together the benefits of water and soil conservation with the economic benefits. With the latter, however, it has been possible to integrate engineering, biological and cultivation methods. Small basins had taken on a new look, and gained benefits from the integration and the scaling up possibilities.

The policy guideline changes have led to some notable achievements and experiences including the following.

The preparation of comprehensive plans and improved standards for developing hills, water, farmlands, woods, and roads. The major task along the Great Wall are to: control the wind erosion; restore the vegetation; promote livestock production; carry out integrated agricultural development of the loess hilly and gully regions; construct wide terraces; adopt cultivation of the large ridges; build underground storage cisterns for irrigation and drinking water for human and animal; and expand fruit, tobacco, potato and sheep, etc. In the plateau and gully areas of the Northern Wei River region, there has been successful development of high quality fruits and woods, especially the apple production, and crop cultivation such as wheat using plastic film, to create a different development pattern and with new primary industries.

(1) Reconstruction of basic croplands at the rate of 2.5 mu per capital to guarantee food selfsufficiency and better living conditions for farmers. With basic croplands, it is guaranteed that farmlands on steep slopes greater than 25° are replanted with trees and grasses. These measures have provided more than 500kg grain for each farmer in Yan'an area, and alleviated soil erosion.

(2) Raising funds and extending mechanical land management. Adopting land management by man and machine is an efficient way for raising management standards and speed up cultivation. Mechanical management now accounts for more than 50 per cent in the Yan'an area and is increasing step by step. The cost of mechanical management of one mu highgrade basic cropland (mainly for wide terrace) is about 700 RMB and the investment is returned in 2—3 years.

(3) Remodelling the land management methods access of the "fourwasteland" Unused hills, unused grasslands,unused waters,unused bottom lands.

They have been sell publicly, which encouraged farmers to manage them activily. Since the end of 1998, two thirds of the 323 thousands ha "fourwasteland" have been sold publicly in Yan'an and some framers had become rich through management and development.

3.3 Some Problems in Sustainable Development 

Although certain achievements had been gained many problems still exist for the longterm sustainable development of the Loess Plateau. Some can be overcome by existing scientific and technological methods, policies and management tools, but others need further research and experimentation.

3.3.1 Natural resources as the main factor restricting sustainable development

(1).The shortage of water resources is the "bottleneck" to increased agriculture productivity. Abundant water resources and their efficient use are essential for the sustainable development of agriculture. Northern Shaanxi Province is a typical semiarid area; its precipitation is about 500 mm and is on low side. Furthermore, the precipitation is not evenly distributed among in seasons, it centralised 60 to 70 percent in July, August and September and caused serious soil erosion. The groundwater resources are scarce except in the sandwindy area along the Great Wall. It is very difficult to exploit groundwater resources because they are generally too deep to pump.

(2) Another constraint to agriculture production is the fragile ecosystem and the barren soil in this area. The ecosystems in Loess Plateau are inherently very fragile. The traditional agricultural practices make soils more barren and the agricultural productivity to fall lower and lower. 

(3) The complicated landscapes increases the reclamation cost and limits competitive advantage. The natural landscapes of the Loess Plateau is varied and complicated. The main types include mountains, hills, gully and plateau. The landscape makes the basic cost of infrastructure, management and reclamation higher than in other regions, and hence restricts its development scale and utilisation efficiency. Under the market economy there is a lack of competitive advantage for large scale farm production. Thus, the basic objective of agriculture development is to meet regional food self sufficiency targets.

3.3.2 Some social and economic factors affecting the sustainable development

(1) The market is underdeveloped.

The underdeveloped market poses two main problems. On the one hand, there is not a fully open agricultural market. On the other hand, the wholesalers and farmers are not familiar with open market mechanisms and the planned economy still plays an important role. In addition, market price is either incorrect or unavailable, and brand consciousness is not well developed some new and important dominant production systems are at risk from market failure. For example, apple production is facing keen market competition, and unless it is possible to foster strong consumer demand or create a top brand, regional development of the apple industry is bound to be held back.

(2) The long-term development is short of potentials.

Ecological agriculture and small basin management with water and soil conservation has played an important role of the Loess Plateau development, but has had limited impact average incomes. During the SAWG field investigation it was noted that some officials often did not give enough consideration to income aspects. Serious thought must be given to improving current income levels, and to wider options for industrialisation and urbanisation. If processing and marketing chains for agricultural products are weak, it is difficult to increase farm output once basic needs have been met. The development of animal husbandry is relatively backward. In particular the role of goats should be reevaluated in the context of stallfeeding and cutandcarry feed stems so that goats do not exert great pressure on the grasslands and slopes.

(3) The human resources development is dropping behind

As in other disadvantaged areas, the backwardness of Northern Shaanxi Province is not only in it's economy, but also in social development, particularly as it is reflected in disparities of human capital. The basic problem is poor education, which limits the ability to absorb, spread and use knowledge. The deficiency in human resources is another important reason for regional poverty.

(4) The environmental problems caused by dry land agriculture

The use of plastic film has been popularised to reduce water shortages and it has brought a great benefits. However pollution caused by film remnants is a growing problem and can not be ignored.

Intensive cultivation of the soil is the main technique used in China's traditional agriculture. But research and experience in western countries indicates that reduced tillage methods and the retention of crop residues on the soil surface can improve soil conservation, raise soil productivity and increase water use efficiency.

3.3.3 The institutional problems in sustainable development 

(1) The issues of the integrated management of river basin

The Loess Plateau lies in the middle reaches of the Yellow River and is faced with complicated and diversified problems relating to water resources utilisation, eco-construction, soil conservation, energy development, deficient supporting and so on. Without a strong authority to coordinate management, the above problems will not be solved. Different public departments with different policies are in conflict with each other. Each department emphasises its own interests, which makes it difficult to reach agreements on the dispersal of funds, the sharing of benefits, and on priority setting.

(2) The weak connection between energy development the local economy

The energy development of Northern Shaanxi Province and surrounding areas is undertaken mainly by large stateenterprises whose operations have no or only weak relations to the local economy, which consequently does not develop quickly. The Jing Bian natural gas purification enterprise visited by SAWG, which is part of the ChinaPetrol Group Co. is a case in point. Only thirtypercent of the equipment and labours comes from the area, and most of the output is exported from the area so the local economic relationships are very limited except if high income employees spur on local markets and encourage some thirdindustries development.

None the less, the income of the energy industry does effect the local economy. For instance, eightythree percent Ansai's income in 1997 came from oil industry. So the modernisation of Northern Shaanxi Province could face great difficulties if a smooth and wellbalanced relationship cannot be established between energy development and the local economy.

(3) The mechanism of research, development and extension

R&D is an important driving forces for economic development. Worldwide experience shows that investment in agriculture research can give high financial returns. But technical invention itself does not necessarily translate into practical application; it must be supported by further investment for local adaptation and application. In recent decades Chinese academics have tended to emphasise basic research and give little consideration to the needs and demands of consumers or users. There was a lack mechanism to accumulate practical techniques and to encourage researchers to develop retional knowledge. With the move to a market economy it is now necessary to change policies and regulations so as to establish a good relationship between basic research and practical applications, foster a science technology market service, and reinforce management to make a greater contribution to the local economy.

4 Basic strategies for sustainable developemt 

The Loess Plateau area is very important to China for eco-environment protection and energy development as well as to the local economy. Its sustainable development must be based on strategies to overcome soil erosion and poverty. Therefore, its agriculture development and that of related industries must satisfy these basic strategies but must also consider the longer-term modernisation objective, which requires the integration of ecoconstruction, agriculture production, energy development, infrastructure and rural construction in order to make better foundation of sustainable development. This proposition is supported by the following four arguments:

(1) Combining the Loess Plateau development and management, expansion of national economy and land integration.e are now in the process of changing development strategies to meet the needs of the 21st century. The centres of food production are gradually moving from south to north. Given increasing population pressure, the Northwest of China will be the last potential area for agricultural development in the next century. The Loess Plateau area may become an important food production centre, especially for wheat, through sound soil management and additional measures to overcome the physical difficulties of present landforms.

The demand for coal and high quality oil and gas is rising because the stage of heavy chemical industrialisation is not finished. This highlights the importance of infrastructure for energy extraction and heavy chemical industrialisation of the Loess Plateau area.

Integrating step by step the development and management of the whole Loess Plateau with that of Northern Shaanxi Province the centre and bring it into China's tenth five year plan.

Investment should be increased in the area, especially for infrastructure and land resources management. With gradual rise of state powers for regional development and rapid increases in poverty alleviation investment, it is possible to speed up the management process. The guiding principles should be "to provide timely help", not seek to "make the good perfect". The key areas should be those with heavy soil erosion and widespread poverty. It is suggested that Loess Plateau management funds should be established by state and provincial governments together with local heavy industrial enterprises as a means of environmental compensation. At the same time, there should be accelerated development of multi source investment schemes, encouragement of foreign and private investment and the creation of efficient loan services.

(3) Using comprehensive measures and exploring new development models for the Loess Plateau. Sole models are inadequate given the coexistence of various problems and the regional differences in natural, social and economic conditions. So comprehensive measures and new development models are necessary. Large scale terraced farmland construction can now assure basic food security, but such practices require high investment, whereas economic development level is still relatively low, and some landscapes are unfavourable for development, so sustainability will still be a difficult issue. We should therefore find alternative ways of terracing, and combine infrastructural and rural improvements, eco-construction and energy development together. For example, we could use heavy machinery and modern techniques to build artificial small plains in heavily eroded areas; and relocate residential and industrial developments to these small plains. These developments might combine soil erosion control and dam construction to find a new agriculture model of reduced tillage and eco-reconstruction.

A good site for a pilot project on the creation of manmade plains would be the Wuding River area where soil erosion is serious, and conditions are right for a step by step scaling up process.

(4) Reinforcing the development of human resources

Human resource development is an essential requirement for sustainable development and the important means of lessening the existing welfare gap between Loess Plateau and East China. There are four important aspects: First, maintenance of the basic family planning policy to create better conditions for economic development. Second, it is necessary to pay more attention to the education and training of local farmers and officials in order to enhance their practical skills and meet the needs of the market economy. Third, more employment should be created, for example, in the management of terraces and construction of basic facilities, in the development of town enterprises and the private economy. It is also necessary to accelerate the flow of human resources among different regions. Lastly, we should insist in "helping the poor to each family", by providing basic public service, life insurance and special opportunities for the poor.

5 Conclusions and recommendations 

5.1 Basic Conclusions 

The climate is generally favourable to agriculture. Most of the soils are very deep and suitable for good crop growth if well managed. These favourable natural resources permitted a productive agriculture that allowed the Zhu, Qin and Han Dynasties to flourish. Since then, however, there has been progressive environmental degradation. Deforestation from the Qin dynasty onwards degraded the land and exposed the fragile soil to water erosion. 

The land degradation resulted from the combination of natural processes and adverse human activities. Increasing population pressure led to extensive clearance and cultivation of highly erodible slopelands, and to some of the most serious soil erosion in the world. Collectively, these two detrimental changes have contributed to progressive loss of the soil organic matter vital for sustainable agriculture, to poverty amongst rural people on the Plateau, and to both frequent floods and seasonal breaks in the flow of the Yellow River and its tributaries, causing loss of life and economic disruption respectively in Provinces downstream of the Plateau. The environmental degradation of the Loess Plateau is therefore an issue for whole China and not just for Shaanxi and Shanxi. 

This situation can be reversed or substantially improved. The environmental degradation and poverty can be overcome in two principal ways. Agricultural R&D in China and elsewhere in the world has provided the technological means to reverse much of the soil erosion and restore soil organic matter levels. Wise development of the huge energy resources of the Loess Plateau can provide the capital needed for the creation of dynamic local economies. It can generate rural and urban employment so that farmer families on the more marginal lands can progressively leave agriculture to gain a better living in the industrial or service sectors, and allow such land to revert to grassland, forest or scrub land in an environmentally sound way. 

Sustainable agriculture on the Loess Plateau will not only conserve the soil and water, but also provide the longterm economic benefits. Therefore, it is necessary to reconsider agricultural and rural planning, and to combine agricultural development with ecoconstruction and urbanization so as to control soil erosion, to provide more employment, to restore forests and grasslands, to reverse the ecological degradation and to alleviate the poverty in Loess Plateau. 

5.2 Basic Recommendations 

5.2.1 Conservation based land and water management

Greater priority should be given to ongoing efforts to transfer Chinese and overseas R&D and experience on more sustainable tillage/cropping practices to Loess Plateau farmers. These practices protect the soil and reduce vulnerability to erosion and drought. A demonstration project should be mounted to train farmers in reduced tillage and stubble retention methods on their own land and then use these farmers and farms in a pilot farmer trains farmer programme for the promotion of the wider uptake of these methods.

Every effort should be made to stop the cultivation and grazing of steep slopes with special emphasis on the measures given in the following recommendations. These include the use of confined feeding systems for livestock, simple reseeding techniques, grass strips instead of machine made terraces, replanting of slope lands with grasses and shrubs to sequester carbon, and creating non agricultural jobs for those currently farming fragile slopelands. It is suggested that various types of ground cover plants should be used widely in apple orchards instead of the bare soil. The benefits of the cover crops include biological N fixation, reduced soil erosion, lower pest attacks, higher soil organic matter and better soil moisture holding capacity. Balanced fertiliser use for major crops like wheat is also important with less N and more P and K. The gains here are both global and national. Balanced fertiliser reduces nitrous oxide emissions as well as farmer's costs and can lower soil erosion.

5.2.2 Integrated management of the Yellow River Basin 

It is necessary to strengthen the integrated management of Yellow River Basin, possibly by reconstructing the Committee of Water Conservancy of Yellow River and it's functions and changing its name to Committee of Integrated Management of Yellow River. The Committee is entitled to bring State agencies together with all 11 provinces that are responsible for, and lie within, the Basin. It could be headed by a senior leader of the State Council to provide the necessary authority for implementation of its strategies. It could draw upon the experience of River Basin Management Authorities in other countries that have similar challenges in managing complex issues of water and land management across a range of jurisdictions. It should provide the coordination, sharing of costs and benefits and regulatory monitoring.

5.2.3 The role of livestock in optimising resource use 

The agricultural structure should be changed and expansion of plant sector should be constrained. More should be done to develop ruminant animal husbandry among farmers of the Loess Plateau, primarily using confined feeding systems to reduce the risk of negative impacts of grazing on steep slopes. Emphasis should be on local breeds of beef cattle, sheep and goats.

Advanced technologies can be very effective for restoring degraded land to provide both grazing land and forage, but they are generally too costly for widespread use. It is therefore recommended that R&D institutions and local officials do more to develop and disseminate "low technology" solutions to overcome soil erosion and the loss of vegetation. In particular, there are local forages, which are or could be as good as some of the imported plant germplasm favoured by scientists. There are also simple native plant reseeding techniques that could achieve vegetation restoration at very low cost.

5.2.4 Improving the client and market focus of agricultural R&D and extension services 

Research institutions and scientists should be encouraged to support the State Ecoconstruction Programme and undertake innovative applied research on sustainable soil and crop management technologies. During the past 40 years research institutions and government agencies have jointly established some integrated management experiments and demonstrations at different scale in various eco-regions of the Loess Plateau. These activities provide some rich scientific and practice experiences that can be extended to similar regions. National and provincial authorities could take a more active role in promoting the adoption of appropriate technologies from other countries even though these may have low acceptance among farmers at the time, such as the reduced tillage technologies mentioned above.

5.2.5 Market development, market competition and comparative advantage 

Further economic development should be based on the optimal utilisation of resources and comparative advantages. Policymakers should assess thoroughly the comparative advantage of local products in national and international markets before encouraging farmers to change their cropping systems. Greater emphasis should be given to: (a) assessing the longterm comparative advantage of the Loess plateau for fruit production; (b) providing more training to farm advisors on marketing aspects; (c) supporting farmers by a better information system about present and potential markets for different crops and their prices and helping them to improve their financial management skills; (d) fruit processing units should be established to widen market opportunities. A concerted effort should be made by the Chinese government to improve the skills of extension and farm service personnel with emphasis on marketing and financial management. 

5.2.6 Getting the best return from investment 

The choice between alternative soil conservation techniques should be based on a more comprehensive analysis of shortterm economic costs and longer-term productivity benefits. Alternative ways of terracing should be devised, which integrate where possible other objectives, such as infrastructures, energy and rural development. For example, through the construction of small to largescale man made plains.

5.2.7 Improving land property right and rural credit services 

Land property rights on the Loess Plateau should be clarified to encourage farmers to increase investment on land, and to improve the rational use and conservation of natural resources.

Rural credit services should be improved, possibly modelled on the current smallscale loan project which has been very effective in raising rural household economic development in less favoured areas.

5.2.8 The Role of the Loess Plateau in national and global development 

Planning of Loess Plateau development should be more closely integrated with national planning so that (a) national and regional grain policies do not have adverse effects on environmental sustainability; (b) people of the region receive a more equitable share of the benefits of the energy resources they provide to China, and (c) so that it can make a major contribution to meeting China's international obligations for climate change mitigation.