Involved personnel

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The Loess Plateau region is well known for its deep loess deposits and serious soil erosion. The average soil loss is 3720 tons/km²/year. According long-term data, the Yellow river sediment load is 1.6 billion tons/year, about 90% of which comes from the Loess Plateau region. The Loess Plateau soil erosion area is 430,000 km², accounting for 81.1 % of total area. Every year about 0.01 to 2 cm topsoil is washed away. One of the reasons for the high erosion rates is the semi-arid climate of the region.

DESIRE can contribute to give a sound scientific data basis for regional resources management, to define suitable indicators and methods of qualitative and quantitative evaluation of land degradation, and to promote a scientific plan for combating soil erosion.

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Added value of DESIRE for stakeholders
Stakeholders think that the DESIRE approach is effective in identifying the causes and effects of land degradation, and can help to make a reasonable strategy of sustainable land management. The evaluation of measures of local and external stakeholders gives a clear understanding of importance and benefit of different technologies.

Study site stakeholder workshops
Land users and government officials.

Limitations of spontaneous implementation of soil and water conservation practices
Since the 1950s, soil and water conservation has been carried out in this region and some progress has been made. The vegetation cover increased and many silt-collection dams have been built. Yet this achievement can not cover the fact that soil erosion is still very serious and land degradation is still a big problem in this region. The main reason for this is that many constraining factors for soil and water conservation still exist. These factors include lack of financial and technical support, and insufficient involvement of local land users in the decision-making process and the low economic return of soil and water conservation practices.

Stakeholder groups

Government/project staff    

• The Office for Soil and Water Conservation in the Yanhe River Basin, and its branches in Ansai and Baota County
• Environment Monitoring Center for Soil and Water Conservation of Yellow River Basin
• Institute of Sand-Control of Shaanxi

Public administration

• agriculture
• forestry    
• land    
• water    
• livestock    
• environment

Research Centres and Universities

• Institute of soil and water conservation, CAS
• Northwest A&F University

Schools        

• Some primary and middle school for environment protection education

Land users

• Local farmers

Sustainability goals

Soil erosion and water shortage are the main limiting factors on the Loess Plateau even after long time of implementation of integrated measures. The sustainable development of agriculture systems and the rural economy without more ecological cost in the Loess Plateau is the main objective of research and projects including of DESIRE.

Source: expert estimate by study site coordinator

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»Stakeholders & their sustainability goals - overview

In the Yan River Basin study site, the same stakeholder workshop and questionnaires that were used to identify existing and potential response strategies (»Identifying strategies: Stakeholder workshop 1) also discussed and identified these driving forces; pressures; impacts; and the policy and regulation environment. This information was then used to inform the choice of »Field experiments, the scenarios used in »Simulated biophysical impact of remediation strategies and their financial viability, and context for the study site-specific »Policy brief recommendations.

Select map type

Land use: type Land use: trends Land use: intensity trend Degradation: type Degradation: extent Degradation: degree Degradation: rate Land conservation: groups Land conservation: extent Land conservation: measures Land conservation: effectiveness Land conservation: effectiveness trends

Comments

Map version: 4Oct11

The main desertification process in the Yan River Basin study site is tillage practice, which results in significant downslope movement of soil and also increases water erosion. For this process, the Desertification Risk Assessment Tool needed data to calculate 190 indicators in 19 map units. Using data from the WOCAT QM database, the required indicators were estimated and imported to the Assessment Tool.   The procedure was applied to all the map units in the study site and the DRI values calculated are shown in Table 1. Table 1: Desertification risk calculation per map unit

The DRI values were mapped for each of the 19 polygons (Map 1)

Map 1: Desertification risk index (DRI)	Map 2: Degree of land degradation (as assessed using the WOCAT mapping method)

The DRI map was compared with the WOCAT QM of the same area (Map 2). It can be seen that the rate of degradation and the measures' effectiveness seen in the WOCAT map correspond closely to the DRI values, with the highest rate of degradation and the lowest measures effectiveness matching up to the highest values of DRI.

Introduction
On the Loess plateau area in the Yan River Basin in China, severe soil erosion is common. This results in deep gully and badland formation on the steeper slopes. To rehabilitate gullies, check dams have been constructed. These limit runoff and sediment delivery downstream and increase water availability for maize. The slopes can be stabilized with terrace constructions. Because of annual rainfall fluctuates between 400 and 1100 mm (average 560 mm), water can be a limiting factor in this region. Soil water conditions are monitored and compared to crops on the slopes, as well as runoff and erosion under different land uses. The erosion is especially important downstream while the conservation measures are tought to be important on site (because of soil moisture increase).

Desertification indices
The main desertification process is water erosion and secondary is water stress, because of erosive soils (loess) and occasional heavy rainfall. Erosion risk is classified as moderate (2.72) in spite of the very steep slope and bare soil and absence of conservation measures. Water stress is classified as low (1.67) probably because of the absence of a direct link between amount of rainfall and water stress in the desertification risk assessment tool.

Applying a terraced situation results in a slight lowering of the water erosion risk which is starnge because apart from choosing terraces as conservation the slope is set to < 2%. The water stress is correctly lowered to “no risk” (1.32).

Bare area on steep slopes with loess soils

Conclusion
The water erosion react counter intuitively to a lowering of the slope from >35% to < 2% with hardly and change, while the water stress is correctly reduced considerably.

First Workshop

A report on the results of the workshop "Land degradation and desertification - existing and potential prevention and conservation strategies" held in Ansai county, Shanxi province, China, 15 to 23 March 2008

Authors and moderators: Wen Zhongming, Wang Fei, Jiao Juying, Jiao Feng

Second Workshop

A report on the results of the workshop "Land degradation and desertification - existing and potential prevention and conservation strategies" held in Ansai county, Yan'an City, Shaanxi province, China, 9 to 11 December 2008

Authors and moderators: Wang Fei, Li Jinpeng, Zhang Jinxin, Wang Qunxing, Song Xiaoyan

A second workshop was held later the same year. This time the local and external stakeholders were not separated, thereby allowing mutual learning by both groups. This was a perceived shortcoming of the first workshop.

Background

The main land use types in the area are cropland, orchards, woodland, wild grassland, vegetable growing and fallow land. Much of the sloping area was converted into forest land or grass land due to the "Conversion of Sloping Farmland into Grass and Forest Program". Orchard areas are close to the villages and provided fruits mainly for self-consumption. Forests are generally found on the steeper and moderately steep parts of the landscape. The main types of land degradation include soil erosion, decrease of fertility and fragmentation of land due to erosion.

Since the 1950s, soil and water conservation has been carried out in this region and some progress has been made. The vegetation cover increased and many silt-collection dams have been built. Yet this achievement can not cover the fact that soil erosion is still very serious and land degradation is still a big problem in this region. The main reason for this is that many constraining factors for soil and water conservation still exist. These factors include lack of financial and technical support, and no involvement of local land users in the decision-making process.

Main causes and effects of land degradation identified in the workshop

Draft outline of strategy for sustainable land management in this region

1) Convert steep slope farmland to forest and grass: this is fundamental to control soil and water loss and improve the quality of land.
2) Construct terraces in gentle slopes: terraces can increase the land productivity, thus reduce the requirement of total land area for food production. Meanwhile terraces can change the hydrological process of slope land and reduce the runoff.
3) Plant cash trees in gentle and south facing slopes
4) Strengthen the construction of irrigation works and improve their management in order to ensure stable yields despite drought.
5) Implement scientific farming practices, including the application of optimum amounts of fertilizer and the use of crop rotation methods.
6) Transform mono-crop systems into a mixed system of crops and grass.

More details ... download the full reports and see results and general conclusions from other study sites
	WP3.1 Stakeholder Workshop 1: China (1st report) 473.42 kB
	WP3.1 Stakeholder Workshop 1: China (2nd report) 580.91 kB
»Identifying strategies: Stakeholder Workshop 1 methodology and summary results from all study sites