1.2 参与该技术评估和文件编制的资源人员和机构的联系方式

有助于对技术进行记录/评估的机构名称（如相关）

Northwest A&F University (NWAFU) - 中国

1.3 关于使用通过WOCAT记录的数据的条件

（现场）数据是什么时候汇编的？:

20/12/2008

编制者和关键资源人员接受有关使用通过WOCAT记录数据的条件。:

是

1.5 请参阅有关SLM方法的问卷

2.1 技术简介

技术定义:

Check dam for land is a structural SLM practice that is constructed in the valley of a watershed in order to slow down the runoff and increase sedimentation. After this, the land quality of the controlling area will increase because soil and water conditions in this place are imporved.

2.2 技术的详细说明

说明:

The check dam is a small dam designed to reduce flow velocity, control soil erosion, and allow to settle on the bed of the valley. The whole system includes main body of dam, spillway, overflow and supporting measures. The check dam for land is a small dam mainly for land after it is filled up by the sediment from upstream area, from several years to 20 years in common, it could be flat land in the valley, not mainly for water collection (different from reservior).

Purpose of the Technology: Check dams in the Loess Plateau are very common. There are many advantages. The check dam could not only reduce the erosion of the gullies, furthermore it retain the sediment in the flow and this decreases the sediment of the Yellow River. The check dam is good quality land for the soils because of the sedimentation of organic matter and other nutrients from topsoil . In this region soils are deep and very fertile because most soil is from the top soil upstream. The soil moisture of check dam is also much better than in any other places in the watershed because the flood should go away from its surface and the water inflitration is great in raining seasons.

Establishment / maintenance activities and inputs: The establishment needs enough money because it has to be safe enough, and the maintenance cost is not so high. The catchment with great soil erosion is better when we considered the formation time of land.

Natural / human environment: The controlling area of check dam for land varies greatly from 30 square km or more. Since the "Grain for Green" Project of China in 1999, the soil erosion on the slope decreased. The time from reservoir to land need more time because there is less and less sediment from upstream and the sedimentation changed slowly.

2.3 技术照片

2.5 已应用该技术的、本评估所涵盖的国家/地区/地点

2.6 实施日期

如果不知道确切的年份，请说明大概的日期:

• 10-50年前

2.7 技术介绍

详细说明该技术是如何引入的:

• 在实验/研究期间

注释（项目类型等）:

It is an old methodology in the Loess Plateau. Since 2003, the check dam had been determined as "Highlight Project " of the Ministry of Water Resources in order to expand in the whole area of the Yellow River Basin.

3.1 该技术的主要目的

• 减少、预防、恢复土地退化

3.2 应用该技术的当前土地利用类型

注释:

Major land use problems (compiler’s opinion): Normally, the bed of valley is V-shaped and is covered by grass and trees. For the seasonal torrent or flash, it is very difficult to plant crops. The gully also cuts down by runoff and extends because of erosion's gravity .

Major land use problems (land users’ perception): It can not be used as agricultural purpose, especially to get more food.

Future (final) land use (after implementation of SLM Technology): Cropland: Ca: Annual cropping

Livestock is grazing on crop residues

如果由于技术的实施而导致土地用途发生变化，则在技术实施前说明土地利的用途。:

Mixed: Ms: Silvo-pastoralism

3.3 有关土地利用的更多信息

该技术所应用土地的供水:

• 雨养

具体说明:

Longest growing period in days: 300Longest growing period from month to month: March to NovemberSecond longest growing period in days: 200Second longest growing period from month to month: April to October

3.4 该技术所属的SLM组

• 横坡措施
• 地表水管理（泉、河、湖、海）

3.5 技术传播

注释:

Total area covered by the SLM Technology is 19.4 m2.

The total area with different measures is almost 2000 km2 . Yanhe River is a first class branch of Yellow River, China. The average channel slope is 3.26‰, and the area of whole basin is 7,687 km2. It is situated in the semi-arid North Temperate Zone with an average annual precipitation varying from 500 to 550 mm, and an average annual air temperature ranging from 8.5 to 11.4℃. It is in hilly gully area of the Loess Plateau covered by loess. The landform is broken seriously. The gully density (the length of channel in one km2) is amount to 2.1 to 4.6 km•km-2. The soil loss is severe all along.
The Ganguyi Hydrology Station (109°48′E, 36°42′N) located in the Ganguyi Town, Baota Country, Yan’an City, Shaanxi Province. The area up Ganguyi Hydrology Station is 5,891 km2, including of Jingbian County(256km2), Zhidan County(708km2), Ansai County(2,699km2) and Baota County(2,228km2). The average annual runoff is 0.22 billion m3, and the runoff modulus accounting for 4,776.36 m3•km-2•yr-1. The average annual sediment flow is 4.776 million tons, and the sediment flow modulus accounting for 8,100 t•km-2•yr-1. The coarse sediment (sediment particle diameter not less than 0.05 mm) flow modulus is 2,430 t•km-2•yr-1 on the Ganguyi Hydrology Station.

3.6 包含该技术的可持续土地管理措施

注释:

Main measures: structural measures

3.7 该技术强调的主要土地退化类型

注释:

Main type of degradation addressed: Wg: gully erosion / gullying

Secondary types of degradation addressed: Wo: offsite degradation effects

Secondary causes of degradation: Heavy / extreme rainfall (intensity/amounts) (It is the reason of erosion that influence the valley.)

3.8 防止、减少或恢复土地退化

具体数量名该技术与土地退化有关的目标:

• 防止土地退化
• 减少土地退化

注释:

Main goals: prevention of land degradation

Secondary goals: mitigation / reduction of land degradation

4.1 该技术的技术图纸

4.2 技术规范/技术图纸说明

The check dam land.

Location: Mazhuang Watershed. Baota County, Yan'an City, Shaanxi China

Date: 2008-10-20

Technical knowledge required for field staff / advisors: high (The design and construction need professional knowledge.)

Technical knowledge required for land users: low (it is easy to use, like alluvial land or wide terrace.)

Main technical functions: control of concentrated runoff: retain / trap

Spillway
Vertical interval between structures (m): 3
Spacing between structures (m): 6
Height of bunds/banks/others (m): 4
Width of bunds/banks/others (m): 6
Length of bunds/banks/others (m): 100

Dam/ pan/ pond
Vertical interval between structures (m): 10
Spacing between structures (m): 100
Depth of ditches/pits/dams (m): 10
Width of ditches/pits/dams (m): 50-100
Length of ditches/pits/dams (m): 300-1000

Construction material (earth): The earth-bank dam is built in Yanhe River Basin.

Construction material (stone): to build the spillways

Slope (which determines the spacing indicated above): 2-5%

If the original slope has changed as a result of the Technology, the slope today is: 2%

Lateral gradient along the structure: 2%

Specification of dams/ pans/ ponds: Capacity 180000m3

Catchment area: 58.3km2m2

Slope of dam wall inside: 30%;
Slope of dam wall outside: 60%

Dimensions of spillways: 3m

Vegetation is used for stabilisation of structures.

4.3 有关投入和成本计算的一般信息

具体说明成本计算所用货币:

• 美元

注明美元与当地货币的汇率(如相关):1美元=:

-2.17

4.4 技术建立活动

	活动	措施类型	时间
1.	Field survey and location selection	结构性的	Before design
2.	Design	结构性的	before construction
3.	Build the dam wall	结构性的
4.	Check and accept	结构性的	After the construction

4.5 技术建立所需要的费用和投入

	对投入进行具体说明	单位	数量	单位成本	每项投入的总成本	土地使用者承担的成本%
劳动力	Building the wall/ field survey and planning	Person/day	180.0	8.8	1584.0	90.0
劳动力	Building the wall/ field survey	Machine/hrs	75.0	43.8	3285.0
施工材料	Stone	m^3	40.0	26.35	1054.0
技术建立所需总成本					5923.0

注释:

Duration of establishment phase: 1 month(s)

4.6 维护/经常性活动

	活动	措施类型	时间/频率
1.	check the dam wall	结构性的	annually

4.7 维护/经常性活动所需要的费用和投入（每年）

	对投入进行具体说明	单位	数量	单位成本	每项投入的总成本	土地使用者承担的成本%
劳动力	check annualy the dam wall	Person/day	15.0	8.8	132.0
技术维护所需总成本					132.0

注释:

Machinery/ tools: crawler type bulldozer, giant jet, tractor, traditional tools, ruler,

The grass on both sides of check wall is natural grass.

4.8 影响成本的最重要因素

描述影响成本的最决定性因素:

The wide of dam wall affects the cost greatly, the wider, more expensive.The labour cost and the distance of rock quarry are also important.

5.1 气候

5.2 地形

说明该技术是否专门应用于:

• 凹陷情况

关于地形的注释和进一步规范:

Altitudinal zone: All check dam and check dam liand here is in such altitudinal zonation.

Slopes on average: Based on 1:100 thousand scale landform map

5.3 土壤

如有可能，附上完整的土壤描述或具体说明可用的信息，例如土壤类型、土壤酸碱度、阳离子交换能力、氮、盐度等。:

Soil depth on average: The depth of Loess varies from nearly 30 m to more than 100 m in Yanhe River Basin. The depth of soil is less than this but it could be nearly 10 meters in commom.

Soil texture: There are more than 50% soil particle which are fine sand with size between 0.05 and 0.1 mm

Soil fertility very low: Lack of N, P and SOM

Topsoil organic matter: <0.5%

Soil drainage / infiltration good: The inflitration in Loess is very fast, but it prones to sealing when flashing

Soil water storage capacity low: Evaporation and drainage are easy

5.4 水资源可用性和质量

关于水质和水量的注释和进一步规范:

Availability of surface water also poor/ none and: Nearly all the branches of Yanhe are seasonal rivers

Availability of surface water medium: It is very stable in this region

Water quality (untreated): Good quality for there are few pollution sources

5.5 生物多样性

关于生物多样性的注释和进一步规范:

It is very stable in this region

5.6 应用该技术的土地使用者的特征

说明土地使用者的其他有关特征:

Land users applying the Technology are mainly Leaders / privileged

Difference in the involvement of women and men: No clear difference

Population density: 50-100 persons/km2

Annual population growth: < 0.5%

(The Check dam for land are build together in some villages for all the people funded by national sub).

Level of mechanization also manual work: The harvesting and other management are by hand

Level of mechanization animal traction: Tillage with animal power mostly

Level of mechanization mechanized/motorized: Tillage with machine in large area check-dam land.

Market orientation of production system mixed: Some production for themselves, but most of production is exchanged on the market.

5.7 应用该技术的土地使用者拥有或租用的平均土地面积

5.8 土地所有权、土地使用权和水使用权

土地所有权:

• 州
• 社区/村庄

土地使用权:

• 个人

用水权:

• 自由进入（无组织）

注释:

Like other rural areas in China

5.9 进入服务和基础设施的通道

6.1 该技术的现场影响

社会经济效应

生产

社会文化影响

生态影响

水循环/径流

土壤

其它生态影响

6.2 该技术的场外影响已经显现

6.3 技术对渐变气候以及与气候相关的极端情况/灾害的暴露和敏感性（土地使用者认为的极端情况/灾害）

渐变气候

渐变气候

	季节	气候变化/极端天气的类型	该技术是如何应对的？
年温度		增加	好

气候有关的极端情况（灾害）

气象灾害

	该技术是如何应对的？
局地暴雨	好
局地风暴	好

气候灾害

	该技术是如何应对的？
干旱	好

水文灾害

	该技术是如何应对的？
比较和缓的（河道）洪水	好

其他气候相关的后果

其他气候相关的后果

	该技术是如何应对的？
缩短生长期	未知

注释:

The better condition of soil and water of check dam land improves the capacity of land tp cope with the changing climate.

6.4 成本效益分析

技术收益与技术建立成本相比如何（从土地使用者的角度看）？

技术收益与技术维护成本/经常性成本相比如何（从土地使用者的角度看）？

注释:

In the first stage, there is no economic output but the check dam is going to fill up with sediments. Afterwards the check dam forms land and with it benefit which would keep up a long time.

6.5 技术采用

• 10-50%

如若可行，进行量化（住户数量和/或覆盖面积）:

675 households in an area of 19.4 km^2 (11 percent of the area)

在所有采用这项技术的人当中，有多少人是自发地采用该技术，即未获得任何物质奖励/付款？:

• 0-10%

注释:

100% of land user families have adopted the Technology with external material support

675 land user families have adopted the Technology with external material support

Comments on acceptance with external material support: All the lands (cropland on the slope or check dam land and forest et al, ) are shared evenly by people. Of course, the work like to build check dam should be finished by all the families.

Comments on spontaneous adoption: No single farmer or family can finish this work because the land right and great investment.

There is a strong trend towards spontaneous adoption of the Technology

Comments on adoption trend: More and more local farmers want to get more check dam land for its long-term benefits.

6.7 该技术的优点/长处/机会

土地使用者眼中的长处/优势/机会
The yield of check dam land is much higher than that on the slope land. How can they be sustained / enhanced? Ask the local people to do more work without payment because they would get more benefits from this land as such.
The yield is stable because the soil moisture is good even in dry year How can they be sustained / enhanced? Use the land efficient and mainten it.

编制者或其他关键资源人员认为的长处/优势/机会
It could reduce the soil erosion originated from the gully. How can they be sustained / enhanced? The local people know this benefit that make them try to find chance to build check dam.
The dam can retain the flow and sediment and reduces the sediment delivery of the downstream. How can they be sustained / enhanced? Ask the people or government of the lower reaches to combat soil erosion through the building of check dams.
The check dam land is fertile and productive How can they be sustained / enhanced? When we make the plan or design the construction, we should better take this into account.
Land is fertile and productive How can they be sustained / enhanced? Improve the awareness of local people to use this technology.
The ceck dam can be used as rural road. How can they be sustained / enhanced? When we make the plan or design the construction, we should better take this into account.

6.8 技术的弱点/缺点/风险及其克服方法

土地使用者认为的弱点/缺点/风险	如何克服它们？
It is too expensive to build the check dam.	Ask the government or other organization and person to invest in check dams.The local people can work together without payment.

编制者或其他关键资源人员认为的弱点/缺点/风险	如何克服它们？
The land in a check dam with less and less soil erosion on the slope, needs longer time to form	It is difficult to overcome this because the control of erosion on slope has higher priority. We can find how to use the water or the temporary wetland.
The input of check dam is quite high.	Ask the government or other organization and person to invest in check dams. The local people can work together without payment.

7.2 参考可用出版物

标题、作者、年份、ISBN:

Soil and water conservation records of Shaanxi Province. 2000. Shaanxi People's Press, Xi'an City, China

可以从哪里获得?成本如何?

Library of ISWC, CAS