技术

Stone wall check dam [埃塞俄比亚]

Yedengay Keter (Amharic)

technologies_1526 - 埃塞俄比亚

完整性: 80%

1. 一般信息

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

关键资源人

SLM专业人员:

Bach Simon

Centre for Development and Environment (CDE), University of Bern

瑞士

SLM专业人员:

Ayele Habtamu

Haramaya University

埃塞俄比亚

有助于对技术进行记录/评估的机构名称(如相关)
Haramaya University (HU) - 埃塞俄比亚

1.3 关于使用通过WOCAT记录的数据的条件

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。:

2. SLM技术的说明

2.1 技术简介

技术定义:

Stone wall check dams are built across a gully to collect alluvial soil and hinder further gully erosion.

2.2 技术的详细说明

说明:

During the 1980s stone walls and terraces were introduced in Ethiopia in order to combat soil erosion. The technology of stone walls or terraces is used to stabilize hills or to refill gullies also in Bati, Ethiopia. Stone walls can form a very strong check dam to rehabilitate gullies even several meters deep.

Purpose of the Technology: Although stone walls can be used for different purposes, this case study is focusing on stone walls used to combat gully erosion. Farmers in the Bati region often use stone walls to rehabilitate gullies if the material is easily accessible, otherwise they may search for alternatives.

Establishment / maintenance activities and inputs: Following procedure is undertaken to build a stone wall check dam: After breaking the stones in the source-area they are transported to the target-area either by hand, by camels or by donkeys, depending on the distance. After digging a foundation for the wall of approximately 30 cm depth, the gap between two rows of big stones 1 m apart is filled up with smaller stones and gravel. These actions are repeated until the desired height and width of the wall are reached

Natural / human environment: The case study site, Bati, lays in an semiarid climatic zone on 1600 m a.s.l. Rainfalls are erratic and the rain sum per year is between 500-1000 mm. The landscape is very hilly with rather steep slopes. As almost in all Ethiopia, the area has a high population density and growth. The agricultural sector is very dominant and lead by a lot of small scale farming with a lot of livestock and small plots of cropland.

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

国家:

埃塞俄比亚

区域/州/省:

Ethiopia / Amhara Region

有关地点的进一步说明:

Bati

注释:

Total area covered by the SLM Technology is 0.6 km2.

Size of the case study watershed.

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:
  • 通过项目/外部干预
注释(项目类型等):

Soil and water conservation measures, including stone wall check dams, were mainly introduced to land users during the 1980s by the government. Sometimes the technology is not adequately performed though. In recent years the local Agricultural Office is teaching farmers how to correctly build soil and water conservation measures not only on a technology basis but to take care of an integrated watershed management.

3. SLM技术的分类

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

农田

农田

  • 一年一作
年作 - 具体指明作物:
  • 谷类 - 高粱
  • corn
具体说明:

Longest growing period in days: 90 Longest growing period from month to month: June until September

牧场

牧场

  • Mixed farming
动物类型:
  • 骆驼
  • 牛 - 奶制品
  • 山羊
  • 家禽
  • 绵羊
  • (Goat/sheep are main meat source (in household or on market))
注释:

Livestock density (if relevant):
> 100 LU /km2

Major land use problems (compiler’s opinion): Deforestation, overgrazing, cultivation of erosion-sensitive areas or steep slopes.

Major land use problems (land users’ perception): Too much soil loss and land degradation, no vegetation cover and poor soil moisture.

Grazingland comments: Livestock is not fenced in. Children herd the animals and watch out that they do not browse through crop fields. In off-farming season crop residues are collected from the field and stored next to the field. Animals are allowed to eat the still remaining residues on the field. After that, the animals are fed by the collected crop residues.

Livestock is grazing on crop residues

3.4 供水

该技术所应用土地的供水:
  • 混合雨水灌溉
注释:

Water supply: Also rainfed

3.5 该技术所属的SLM组

  • 横坡措施

3.6 包含该技术的可持续土地管理措施

结构措施

结构措施

  • S1:阶地
  • S5:大坝、集水斗、水池
  • S6:墙、障碍物、栅栏、围墙
注释:

Main measures: structural measures

3.7 该技术强调的主要土地退化类型

土壤水蚀

土壤水蚀

  • Wt:表土流失/地表侵蚀
  • Wg:冲沟侵蚀/沟蚀
注释:

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

Secondary types of degradation addressed: Wt: loss of topsoil / surface erosion

Main causes of degradation: deforestation / removal of natural vegetation (incl. forest fires) (Deforestation for the past 30 years.), over-exploitation of vegetation for domestic use (Wood collection for cooking and construction.), overgrazing (50% of the watershed area are cultivated - big grazing pressure on remaining land), other human induced causes (specify) (Cultivation of very steep slopes.), change of seasonal rainfall (Erratic rainfall.), Heavy / extreme rainfall (intensity/amounts) (If there is rain, it is intensive.), population pressure (High population pressure.), poverty / wealth (Poor facilities.)

Secondary causes of degradation: soil management (Poor soil management practices and lack of awareness.), crop management (annual, perennial, tree/shrub) (Annual cropping.), droughts (The research area is considered rather dry.), land tenure (If the land is rented, it is poorly managed.), inputs and infrastructure: (roads, markets, distribution of water points, other, …) (Poor access to fertilizer. Bad infrastructures.), education, access to knowledge and support services (Lack of awareness for soil degradation.), Low productivity of the land (As a consequence seeking for new/larger areas to increase production.)

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:
  • 减少土地退化
  • 修复/恢复严重退化的土地
注释:

Secondary goals: mitigation / reduction of land degradation

4. 技术规范、实施活动、投入和成本

4.1 该技术的技术图纸

技术规范(与技术图纸相关):

Stone wall check dams as they can be found in the region of Bati. The approximately 1 m wide gap between two rows of larger stones is filled up with small stones or gravel. This is done for every new level of the wall until the wall reaches its final height. The first row of stones is placed in the top 30 cm of the ground and on each side the dam is entering the hill to some extent. After a wall has silted up, the height is increased by other rows of stones until desired dimension is reached. Walls up to 5 m can be found in the case study site.

Location: South-West of Bati. Bati Woreda, Amhara Region, Ethiopia

Date: 26.04.2011

Technical knowledge required for field staff / advisors: moderate (To teach the farmers how to perform an integrated watershed management.)

Technical knowledge required for land users: high (To build a robust check dam there is a lot of knowledge needed.)

Main technical functions: control of concentrated runoff: retain / trap, control of concentrated runoff: impede / retard, reduction of slope angle, reduction of slope length, increase / maintain water stored in soil, sediment retention / trapping, sediment harvesting

Secondary technical functions: water harvesting / increase water supply, improvement of water quality, buffering / filtering water

Retention/infiltration ditch/pit, sediment/sand trap
Depth of ditches/pits/dams (m): 6
Width of ditches/pits/dams (m): 10
Length of ditches/pits/dams (m): 1

If the original slope has changed as a result of the Technology, the slope today is: 0%

作者:

Simon Bach, CDE, Bern, Switzerland

4.2 有关投入和成本计算的一般信息

其它/国家货币(具体说明):

Ethiopian Birr

如相关,注明美元与当地货币的汇率(例如1美元=79.9巴西雷亚尔):1美元=:

16.82

注明雇用劳工的每日平均工资成本:

1.00

4.3 技术建立活动

活动 时间(季度)
1. Preparation of the stones (500 person days needed). During dry season.
2. Transportation of the stones (depending on the distance). During dry season.
3. Digging a foundation of 30 cm depth (165 person days needed). During dry season.
4. Building of the stone wall (500 person days needed). During dry season.

4.4 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 Labour ha 1.0 1165.0 1165.0 50.0
设备 Tools ha 1.0 5.0 5.0 100.0
技术建立所需总成本 1170.0
技术建立总成本,美元 69.56

4.5 维护/经常性活动

活动 时间/频率
1. Prepare the stones (250 person days needed). During dry season if needed.
2. If dam is silted up, increasing the height by 0.5 m (250 person days needed) Every year in dry season.

4.6 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 Labour ha 1.0 500.0 500.0 50.0
设备 Tools ha 1.0 5.0 5.0 100.0
技术维护所需总成本 505.0
技术维护总成本,美元 30.02
注释:

Machinery/ tools: Shovel, digging hoe, iron rod.

Total costs of a hectare were calculated for a wall of 100 m length and 1 m of height every 20 m (500 m total wall) in the year 2011. Tool prices were estimated and labor costs were calculated with a daily wage of 1$.

4.7 影响成本的最重要因素

描述影响成本的最决定性因素:

Rough topology in the area, questionable availability of construction materials if they are not found nearby.

5. 自然和人文环境

5.1 气候

年降雨量
  • < 250毫米
  • 251-500毫米
  • 501-750毫米
  • 751-1,000毫米
  • 1,001-1,500毫米
  • 1,501-2,000毫米
  • 2,001-3,000毫米
  • 3,001-4,000毫米
  • > 4,000毫米
有关降雨的规范/注释:

Erratic rainfall (rainseason from June until September)

农业气候带
  • 半干旱

Thermal climate class: tropics (LGP shorter than 90 days.)

5.2 地形

平均坡度:
  • 水平(0-2%)
  • 缓降(3-5%)
  • 平缓(6-10%)
  • 滚坡(11-15%)
  • 崎岖(16-30%)
  • 陡峭(31-60%)
  • 非常陡峭(>60%)
地形:
  • 高原/平原
  • 山脊
  • 山坡
  • 山地斜坡
  • 麓坡
  • 谷底
垂直分布带:
  • 0-100 m a.s.l.
  • 101-500 m a.s.l.
  • 501-1,000 m a.s.l.
  • 1,001-1,500 m a.s.l.
  • 1,501-2,000 m a.s.l.
  • 2,001-2,500 m a.s.l.
  • 2,501-3,000 m a.s.l.
  • 3,001-4,000 m a.s.l.
  • > 4,000 m a.s.l.
关于地形的注释和进一步规范:

Altitudinal zone: 1501-2000 m a.s.l. (The study site is located at 1600m a.s.l.)
Landforms: Hill slopes (ranked 1) and valley floors (ranked 2)
Slopes on average: Hilly (ranked 1), rolling (ranked 2) and steep (ranked 3)

5.3 土壤

平均土层深度:
  • 非常浅(0-20厘米)
  • 浅(21-50厘米)
  • 中等深度(51-80厘米)
  • 深(81-120厘米)
  • 非常深(> 120厘米)
土壤质地(表土):
  • 粗粒/轻(砂质)
  • 中粒(壤土、粉土)
表土有机质:
  • 低(<1%)
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: Very shallow (ranked 1) and shallow (ranked 2)
Soil textur: Coarse/light (ranked 1) and medium (ranked 2)
Soil fertility is low
Soil drainage/infiltration is poor
Soil water storage capacity is medium

5.4 水资源可用性和质量

地下水位表:

5-50米

地表水的可用性:

匮乏/没有

水质(未处理):

不良饮用水(需要处理)

关于水质和水量的注释和进一步规范:

Ground water table: Unknown
Availability of surface water is poor/none (Only during rainy season)
Water quality (untreated): Poor drinking water (treatment required, mostly groundwater)

5.5 生物多样性

物种多样性:
关于生物多样性的注释和进一步规范:

Relative to other parts of Ethiopia.

5.6 应用该技术的土地使用者的特征

生产系统的市场定位:
  • 生计(自给)
非农收入:
  • 低于全部收入的10%
相对财富水平:
  • 丰富
个人或集体:
  • 个人/家庭
机械化水平:
  • 手工作业
  • 畜力牵引
性别:
  • 男人
说明土地使用者的其他有关特征:

Land users applying the Technology are mainly common / average land users
Population density: 100-200 persons/km2
Annual population growth: 6%
1% of the land users are rich (Adopt the most of SWC technologies).
19% of the land users are average wealthy.
89% of the land users are poor.
Off-farm income specification: Off-farm income has low importance.
Level of mechanization: Animal traction (Plowing by oxen, ranked 1) and manual labour (ranked 2)
Market orientation cropland: Subsistence
Market orientation grazing land: Goat/sheep are main meat source (in household or on market).

5.7 应用该技术的土地使用者使用的平均土地面积

  • < 0.5 公顷
  • 0.5-1 公顷
  • 1-2 公顷
  • 2-5公顷
  • 5-15公顷
  • 15-50公顷
  • 50-100公顷
  • 100-500公顷
  • 500-1,000公顷
  • 1,000-10,000公顷
  • > 10,000公顷
这被认为是小规模、中规模还是大规模的(参照当地实际情况)?:
  • 小规模的

5.8 土地所有权、土地使用权和水使用权

土地所有权:
  • 个人,有命名
用水权:
  • 自由进入(无组织)

5.9 进入服务和基础设施的通道

健康:
  • 贫瘠
  • 适度的
教育:
  • 贫瘠
  • 适度的
技术援助:
  • 贫瘠
  • 适度的
就业(例如非农):
  • 贫瘠
  • 适度的
市场:
  • 贫瘠
  • 适度的
能源:
  • 贫瘠
  • 适度的
道路和交通:
  • 贫瘠
  • 适度的
饮用水和卫生设施:
  • 贫瘠
  • 适度的
金融服务:
  • 贫瘠
  • 适度的

6. 影响和结论性说明

6.1 该技术的现场影响

社会经济效应

生产

作物生产

降低
增加

畜牧生产

降低
增加

生产故障风险

增加
降低
注释/具体说明:

Conservation of soil water

生产区域

降低
增加
注释/具体说明:

Gullies are transformed to fields. Structure needs space but also gains space

土地管理

妨碍
简化
注释/具体说明:

Structure as a new obstacle

水资源可用性和质量

饮用水的可用性

降低
增加
收入和成本

农业投入费用

增加
降低
注释/具体说明:

alluvial soil is relatively fertile

农业收入

降低
增加
注释/具体说明:

new fields lead to higher productivity

收入来源的多样性

降低
增加

经济差异

增加
降低
注释/具体说明:

additional income due to new fields

工作量

增加
降低
注释/具体说明:

Gully is now flat land and traversable but needs establishment and maintenance work

社会文化影响

食品安全/自给自足

减少
改良
注释/具体说明:

Additional space for new fields

社区机构

削弱
加强

国家机构

削弱
加强

SLM/土地退化知识

减少
改良
注释/具体说明:

best practices may spread further on

冲突缓解

恶化
改良
注释/具体说明:

upstream and downstream dialog

Improved livelihoods and human well-being

decreased
increased
注释/具体说明:

Accumulation of soil leads to new space for fields and additional food security or even income (if crop surplus is sold).

生态影响

水循环/径流

水量

降低
增加
注释/具体说明:

increased soil moisture

水的回收/收集

减少
改良
注释/具体说明:

dam blocks water flow

地表径流

增加
降低
注释/具体说明:

increased infiltration, reduced flow velocity

地下水位/含水层

下降
补水
注释/具体说明:

increased infiltration

土壤

土壤水分

降低
增加
注释/具体说明:

Dam blocks water flow but can lead to the fact that additional groundwater may be logged

土壤流失

增加
降低
注释/具体说明:

alluvial accumulation behind the structure

养分循环/补给

降低
增加
生物多样性:植被、动物

生物量/地上C

降低
增加

植物多样性

降低
增加

动物多样性

降低
增加

有益物种

降低
增加

栖息地多样性

降低
增加

害虫/疾病控制

降低
增加
注释/具体说明:

new habitat for rodents etc.

减少气候和灾害风险

洪水影响

增加
降低
注释/具体说明:

flood controll by stone check dams

碳和温室气体的排放

增加
降低

6.2 该技术的场外影响已经显现

水资源可用性

降低
增加
注释/具体说明:

possibility of spring development

旱季稳定可靠的水流

减少
增加
注释/具体说明:

if a spring can develop

下游洪水

增加
减少
注释/具体说明:

increased infiltration/reduced flooding but also less downstream river flow

下游淤积

增加
降低
注释/具体说明:

trapping of the sediments by the structure

地下水/河流污染

增加
减少
注释/具体说明:

trapping of the sediments by the structure. No off site sediment yields available anymore.

缓冲/过滤能力

减少
改良
注释/具体说明:

increased infiltration

风力搬运沉积物

增加
减少

对邻近农田的破坏

增加
减少
注释/具体说明:

due to gully rehabilitation

对公共/私人基础设施的破坏

增加
减少
注释/具体说明:

due to gully rehabilitation

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 增加或减少 该技术是如何应对的?
年温度 增加

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
局地风暴
气候灾害
该技术是如何应对的?
干旱
水文灾害
该技术是如何应对的?
比较和缓的(河道)洪水

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

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)?
短期回报:

非常消极

长期回报:

积极

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)?
短期回报:

轻度消极

长期回报:

积极

注释:

Big labour input for establishment. Also maintenance needs some work every year. But also high benefit by additional farming land gained due to the check dams.

6.5 技术采用

注释:

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

Comments on acceptance with external material support: In the past 6 years the local Agricultural Office has supported farmers to treat their watersheds with SWC technologies based on a food for work programme. Today farmers build the structures on their own but seek support.

There is a moderate trend towards spontaneous adoption of the Technology

Comments on adoption trend: Most of the farmers build SWC technologies (includin stone check dams in gullies) because of the food for work programme

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 stone check dams are conserving soil and moisture.

How can they be sustained / enhanced? Maintain the dams.
Due to alluvial soil there is additional farming land and therefore increased productivity.

How can they be sustained / enhanced? Take care of the walls as well of the surrounding area and the whole watershed.
编制者或其他关键资源人员认为的长处/优势/机会
Stone check dams are a quite durable structure.

How can they be sustained / enhanced? Stability could be enhanced by additional technologies e.g. similar as gabbions or planting of trees/shrubs in front of the wall to reduce collapsing possibility.
The structure collects alluvial soil which can be plowed and used as new farming fields.

How can they be sustained / enhanced? Structure maintenance is important. If the dam fails, the field is washed out as well.
The technology is widely used around the world (perhaps with local adaptations) and is therefore well documented.

How can they be sustained / enhanced? Keep on with documentation and monitoring of limitations and potentials of stone check dams around the world.

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?
The Land users could not tell any disadvantages of the technology. Could be an indicator that there is enough spare time to build and maintain structures during off-farming season.
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?
Large labour input at establishment and during maintenance period. Possibly by machinery but it is very expensive.
During time of establishment/maintenance there is no time for farming activites. These activities can therefore be seen as hidden costs. Perhaps a "professional" team that takes care of check dams and is payed for it.

7. 参考和链接

7.1 信息的方法/来源

7.2 参考可用出版物

标题、作者、年份、ISBN:

Bach S. (2012) Potentials and limitations of Jatropha curcas as a multipurpose crop for sustainable energy supply and soil and water conservation - a case study in Bati, Ethiopia, using the WOCAT approach. Unpublished master’s thesis, Centre for Development and Environment, University of Bern.

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