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/评估的项目名称（如相关）

Book project: Guidelines to Rangeland Management in Sub-Saharan Africa (Rangeland Management)

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。:

是

1.4 所述技术的可持续性声明

这里所描述的技术在土地退化方面是否存在问题，导致无法被认为是一种可持续的土地管理技术？:

否

2.1 技术简介

技术定义:

These are constructions stretching across the sand filled dry riverbed, down towards the impermeable floor of the riverbed. They are totally submerged into the ground. For example by fully covering after construction by sand. This are done along dry rivers with huge sand deposits, which has high yield potential and where water can be easily extracted. The aim is to raise groundwater tables and increase the storage capacity for water withdrawals.

2.2 技术的详细说明

说明:

The technology is applied in northern rangeland of Isiolo County which is managed under communal management systems. The aim of technology to reduce pasture and water availability imbalances. The dimensions of sub-surface dam include: a length of water spread (103m),width of the dam (15m), width of water spread (18m), effective dam height (2m), volume of retained sand (103 x 0.5(15 +18) x0.5 x2.0 = 5098.50m3) and the volume of water that can be abstracted from the sand bed (25/100x 5098.50m3 = 1274.6.36m3).
The technology functions as underground water storage infrastructure and the typical activities include, excavation of top porous soil, excavation of sample pits within the excavated area, checking filtration rates of soil, compaction of soil on which dam liners are laid, smoothing the sharp liners along which the dam liners are laid, making grooves to anchor the dam liner, laying the dam liner, anchoring the dam liner with a mixture of cement, water proof and sand with water (motor) and finally drying of the motor and filling back of sand.
The development of Sub-Surface Dams (SSDs) was done through Cash for Work program where local labours comprising of 40-50 persons are engaged in excavation, compactions and developing the liners. Farm tools like jembe, panga, spades and human labour are required to develop the SSD. The technology improves water supply/availability, thereby extending the period of livestock grazing in areas where typically water is depleted before the pasture hence improves water access for livestock in ways that support wider management and utilization of the rangeland and as such strength the resilience of pastoralists to droughts. This effectively gives pastoral groups, an extra grazing time (typically 2 extra months), a period usually not too long to encourage land degradation through over-grazing but long enough to enable pastoralist utilize the remaining pasture in wet season grazing areas. In so doing, the technology enable balanced use of vast communal lands without livestock retreating to dry season grazing areas.
In the process of the landscape level participatory planning with the communities: i) they identified different challenges, including need for decommissioning certain water points that they consider are contributing to over grazing and also attracting other communities, hence drive frequent conflicts, secondly, ii) they mapped areas in the rangeland where there is mismatch between water and pasture availability, most of these areas are in wet season grazing areas. So the next discussion was on what strategic water infrastructures that will enable herders to graze for 2 -3 extra months to enable them utilize the grass before they migrate to the traditional dry season grazing areas. So by design, the technology should only yield water that can allow settling for those extra months, not longer to the detriment of the rangeland
The technology was instrumental in fostering both balanced utilization of land and strengthening sustainable use of the vast rangeland by ensuring that herders utilize available pastures in the wet seasons grazing areas before moving to dry seasons grazing areas. The water stored through the technology stays longer, in this case study, the water lasted for 5 months after the end of the rainy season .
The area receives bimodal rainfall, long rain in March-May and short rain in November-December. With changing seasons/climate, the dry seasons can last up to 1 year in case of rainfall failure. Typically, dry seasons are 6-7 months (May- November).
Normally, the water is depleted within 2 months after the rainy period. The technology is also cheap and easy to understand and construct (especially in areas with clay as the underlying impermeable material) with a possibility of the communities to be taught how to identify suitable site and the entire process of construction. However, in areas without clay soil, the excavation of clay and transportation can be labour intensive and expensive.

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

2.7 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

3.1 该技术的主要目的

• 改良生产
• 减少、预防、恢复土地退化
• 适应气候变化/极端天气及其影响
• 减缓气候变化及其影响
• 创造有益的经济影响
• 创造有益的社会影响

3.2 应用该技术的当前土地利用类型

注释:

Communal grazing area that is shared by 2 and more pastoral groups

3.4 供水

该技术所应用土地的供水:

• 雨养

3.5 该技术所属的SLM组

• 畜牧业和牧场管理

3.6 包含该技术的可持续土地管理措施

3.7 该技术强调的主要土地退化类型

注释:

Mismatch of pasture and water resources - there are areas where pastures are plenty but surface rain water is depleted earlier than pasture.

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:

The SSD technology increase water availability is period immediately after the rain, hence ensuring better pasture utilization and more sustainable use of land.

4.1 该技术的技术图纸

4.2 有关投入和成本计算的一般信息

具体说明成本和投入是如何计算的:

• 每个技术单元

具体说明成本计算所用货币:

• 美元

4.3 技术建立活动

	活动	时间（季度）
1.	Removing sand over dyke and man-days for excavating and transporting soil to dam site	21 days for 45 casual labourers
2.	Building and compaction soil in dam wall	3 days for 45 casual labourers
3.	Supplying water for compaction	0.5 day for 45 casual labourers
4.	Back-filling sand on dam	1 day for 45 casual labourers
5.	Supplying water for compacting clay in dam wall	2 days for 45 casual labourers
6.	Compacting soil and placing liners	12 days for 45 casual labourers

注释:

The construction of SSD was done through “Cash for work” which is participatory process that involves community mobilization, identification of beneficiaries and formation of “Cash for work” committees, registrations and verification of beneficiaries and implementation/supervision of the work.

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	tools - jembe, spade etc.	pieces	80.0	5.33	426.4
劳动力	Removing sand over dyke and Man-days for excavating and transporting soil to dam site	per day	945.0	4.0	3780.0
劳动力	Building and compaction soil in dam wall	per day	135.0	4.0	540.0
设备	Supplying water for compaction	per day	22.5	4.0	90.0
设备	Back-filling sand on dam	per day	45.0	4.0	180.0
设备	Supplying water for compacting soil in dam wall	per day	90.0	4.0	360.0
设备	Compacting soil and placing liners	per day	540.0	4.0	2160.0
技术建立所需总成本					7536.4

注释:

As stated, the cash for work approach means that people get paid 4 USD per day for working on SSD until completion. There are phases where people participated in preliminary phases in meetings and consultation without payments but the actual work was done on cash for work basis.

4.5 维护/经常性活动

	活动	时间/频率
1.	Training of communities to manage and maintain the structures	yearly

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 for site protection and maintenance of hygiene	per site	10.0	100.0	1000.0
技术维护所需总成本					1000.0

注释:

Water User Associations on the sites are trained on the management of the structures on behalf of the community e.g. on the protection of structure and hygiene maintenance.

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:

Distance of the sub-surface dam from villages, extent of destruction by floods and human activities

5.1 气候

5.2 地形

说明该技术是否专门应用于:

• 凹陷情况

5.3 土壤

5.4 水资源可用性和质量

水的盐度有问题吗？:

否

该区域正在发生洪水吗？:

否

5.5 生物多样性

5.6 应用该技术的土地使用者的特征

5.7 应用该技术的土地使用者使用的平均土地面积

5.8 土地所有权、土地使用权和水使用权

土地所有权:

• 社区/村庄

土地使用权:

• 社区（有组织）

用水权:

• 社区（有组织）

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

水资源可用性和质量

生态影响

减少气候和灾害风险

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）

气候有关的极端情况（灾害）

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

注释:

The technology copes very well with floods as the construction is embedded in the sand and thus very well protected.

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:

The technology has limited running and maintenance costs once its done fairly well.

6.5 技术采用

• 1-10%

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

• 0-10%

6.6 适应

最近是否对该技术进行了修改以适应不断变化的条件？:

否

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 technology created opportunity to graze in wet season grazing areas for an averge extra 2 months period after rainy seasons. The technology has provided additional water that gave herders extra days to graze in wet season areas and utilize the pasture that would have been unutilized due to water constrains. In so doing, the land users utilized the pasture without retreating to traditional dry season grazing areas.
The extra grazing months has reduced overall livestock mortality during droughts and also improved resilience of pastoral community.
The distance travelled and effort required to access water was reduced. Community members reported reduced distances covered and time spent in search of water for livestock. In some instances the distance reduced from 12-15 Km to 3 Km. Community members also mentioned reduction in conflict incidences over water resources in some areas due to adequate supply of water as a result of construction of water infrastructure.
The balanced utilization of the grazing area through SSD water provision, enables herd to graze in wet season grazing for slightly longer period and utilize pasture optimally, this however, does not mean that during that garzing period, there will be overgrazing. The volume of water available restricts the number of animals sustained by the grazing area.

编制者或其他关键资源人员认为的长处/优势/机会
The technology has created an opportunity to optimally use the grazing area and overall reduced land degradation. The technology Improves access to water for livestock in ways which promote more sustainable management of rangeland resources and as such strengthening the resilience of local communities.
The validation process prior to construction of the SSD is draws critical lessons of identifying and agreeing on where to construct the SSD in a way that fit within broader sustainable rangeland management in a manner that ensured sustainable and efficient utilization of pasture and browse resources in targeted areas. The increase in water supply allowed livestock to graze additional 2-3 months in target areas before shifting to dry grazing areas where previously they migrated before exhausting the pasture and browse resources due to water scarcity. The dry season grazing area is towards Merti, in Kom and Sabarwawa where there are deep boreholes, under, lock and key and only opened during dry seasons. In typical year, the dry season period is about 7 months. But when one rain season fail it goes to about 11 months.

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？
When the construction season for SSD is not well planned, there is likelihood/risks of the dams being washed away by flash floods.	Better planning and timing of the development of SDD, just slightly before the onset of rainfall.

7.1 信息的方法/来源

7.3 链接到网络上的相关信息

标题/说明:

Promoting resilience by influencing water infrastructure development in community managed rangelands of Kenya

URL:

https://portals.iucn.org/library/sites/library/files/documents/2014-088.pdf

标题/说明:

Balancing water infrastructure in community-managed rangelands in the arid and semi-arid lands of Kenya

URL:

https://portals.iucn.org/library/sites/library/files/documents/2014-089.pdf