技术

Check dams from stem cuttings [尼加拉瓜]

Diques de postes prendedizos (Spanish)

technologies_1719 - 尼加拉瓜

完整性: 73%

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:
SLM专业人员:

Rodriguez Roger

PASOLAC

尼加拉瓜

SLM专业人员:

Mongalo Reinerio

Sociación Tierra y Vida (AT&V)

尼加拉瓜

有助于对技术进行记录/评估的项目名称(如相关)
Book project: where the land is greener - Case Studies and Analysis of Soil and Water Conservation Initiatives Worldwide (where the land is greener)

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。:

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?:

2. SLM技术的说明

2.1 技术简介

技术定义:

Gully rehabilitation by check dams made of stem cuttings from trees. These living barriers retard concentrated runoff and fill up the gullies gradually with sediment.

2.2 技术的详细说明

说明:

Stem cuttings from specific tree species have the ability to strike roots and continue growing after being planted into the earth. In this case study local species have been used to create check dams in gullies: these include jinocuebo (Simaroubaceaes bombacaceaes, and also jobo, tiguilote, pochote from the same family). Other suitable species are jocote (Spondias purpurea) and madero negro (Gliricidia sepium). As an option the pinapple-like piñuela (Bromelia pinguin) can be planted in association with the stem cuttings to further reinforce the system. Tree stems are cut into pieces 5-15 cm thick and 1.5-2.5 m long, depending on the depth of the gully. The cuttings are planted to half of their length, and formed into semi-circular barriers (see diagram). The dams retard runoff and thus retain eroded sediment. Spacing between dams depends on the gradient of the gully bed. For example on a 15% slope it is recommended to build a dam every 4 meters (see spacing under establishment activities). Between dams, the gully gradually fills up with eroded soil, the speed of the runoff is further reduced and agricultural land that has been divided by the gully is reconnected. Large and deep gullies may change over time into a sequence of narrow fertile terraces where crops can be grown.

However, the check dams should be seen as part of an integrated catchment management and protection plan, and thus be supported by other SWC measures on the lateral slopes, such as retention ditches and/or live barriers laid out along the contour. Erosion and runoff control on the sides of each gully is an essential part of the rehabilitation process. These check dams of rooted poles are more robust and durable than stone dams in soils of sandy/ loamy texture. On moderate and steep slopes a combination of stem cutting and stone dams is recommended.

After two to three years the barriers should be pruned - yielding wood and fodder. Dead poles should be replaced and the dam widened if necessary.

In this case study the dams are constructed in a semi-arid region with erratic rainfall where gullies are common on agricultural land, be it cropland or grazing land. The land users are mainly peasant farmers, growing crops for subsistence on smallholdings, and living in very poor conditions. This system of gully rehabilitation is promoted by an NGO entitled ‘Asociación Tierra y Vida’ through farmerto-farmer (campesino a campesino) extension.

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:

尼加拉瓜

区域/州/省:

Santa Teresa, Paso de la Solera

有关地点的进一步说明:

Carazo, Nicaragua

注释:

Total area covered by the SLM Technology is 5 km2.

2.6 实施日期

如果不知道确切的年份,请说明大概的日期:
  • 不到10年前(最近)

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. 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
  • 降低灾害风险

3.2 应用该技术的当前土地利用类型

农田

农田

  • 一年一作
具体说明:

Longest growing period in days: 100, Longest growing period from month to month: May to August; Second longest growing period in days: 90, Second longest growing period from month to month: September to November

牧场

牧场

注释:

Major land use problems (compiler’s opinion): There is a range of factors that limit agricultural production in the area: soil degradation, extensive gully formation on crop land, low soil fertility, lack of inputs for crop production, erratic precipitation. Also, lack of interest/knowledge and lack of resources hinder the implementation of SWC measures.

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

  • 横坡措施

3.6 包含该技术的可持续土地管理措施

植物措施

植物措施

  • V5:其它
结构措施

结构措施

  • S4:平沟、坑
  • S5:大坝、集水斗、水池
注释:

Specification of other vegetative measures: stem cuttings; live barriers along contour (supp.)
Specification of other structural measures: check dams; retention ditches

3.7 该技术强调的主要土地退化类型

土壤水蚀

土壤水蚀

  • Wg:冲沟侵蚀/沟蚀

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:
  • 修复/恢复严重退化的土地

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):

Stem cuttings planted in gullies to form living check dams: recently planted (left) and cuttings that have begun to take root and sprout, resulting in the gully becoming filled with trapped sediment (right).

Technical knowledge required for field staff / advisors: low
Technical knowledge required for land users: moderate
Main technical functions: control of concentrated runoff: retain / trap, levelling of land
Secondary technical functions: reduction of slope angle, reduction of slope length

Construction material (wood): jinocuebo (Simaroubaceaes bombacaceaes, and also jobo, tiguilote, pochote from the same family), j
Slope (which determines the spacing indicated above): 15%

作者:

Mats Gurtner

4.3 技术建立活动

活动 时间(季度)
1. Calculate and mark spacing between structures. efore rainy season (April/May)
2. Cut poles out of selected local trees (diameter: 5–15 cm,length: 1.5–2.5 m depending on gully depth). before rainy season (April/May)
3. Dig small semi-circular ditches at the gully bottom (the depth of theditch is half the length of the cuttings). before rainy season (April/May)
4. Plant the cuttings vertically into the ditch; put the thicker cuttingsin the middle of the gully where runoff velocity is higher. efore rainy season (April/May)
5. Fill ditch with excavated earth to fix the cuttings. before rainy season (April/May)
6. Water to encourage rooting. before rainy season (April/May)

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 1.0 100.0 100.0 100.0
设备 tools ha 1.0 20.0 20.0
设备 wheelbarrow ha 1.0 10.0 10.0 100.0
施工材料 wood ha 1.0 60.0 60.0 100.0
技术建立所需总成本 190.0
技术建立总成本,美元 190.0
注释:

Duration of establishment phase: 2 month(s)

4.5 维护/经常性活动

活动 时间/频率
1. Biotrampas: pruning the trees every three years.
2. Cut-off drains: clearing of sediment, cutting bushes and grasses.
3. Stone check dams: pruning trees and bushes every three years. After fullsedimentation, the dam may be increased in height.
4. Wooden check dams: pruning trees and bushes every three years.

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 30.0 30.0 100.0
施工材料 wood ha 1.0 5.0 5.0 100.0
技术维护所需总成本 35.0
技术维护总成本,美元 35.0
注释:

Costs are calculated for a 100 m long, 2 m wide and 1 m deep gully with check dams every 4 m, on the basis of one gully per hectare.

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:

The wood (for poles) belongs to the land users themselves, thus the ‘cost’ does not involve purchase.

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
农业气候带
  • 半干旱

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.

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):
  • 中粒(壤土、粉土)
  • 细粒/重质(粘土)
表土有机质:
  • 低(<1%)

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)
  • 混合(生计/商业)
非农收入:
  • 收入的10-50%
个人或集体:
  • 个人/家庭
说明土地使用者的其他有关特征:

Off-farm income specification: temporary or permanent migration, particularly young people

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,未命名
  • 个人,有命名
土地使用权:
  • 租赁
  • 个人

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
注释/具体说明:

where gullies planted

饲料生产

降低
增加
注释/具体说明:

eg madero negro=Gliricidium sepium

木材生产

降低
增加
注释/具体说明:

medium term

收入和成本

农业收入

降低
增加

工作量

增加
降低
注释/具体说明:

during establishment phase

社会文化影响

社区机构

削弱
加强

冲突缓解

恶化
改良

improves relationships between land users

decreased
increased

生态影响

土壤

土壤水分

降低
增加

土壤流失

增加
降低

养分循环/补给

降低
增加

6.2 该技术的场外影响已经显现

下游洪水

增加
减少

下游淤积

增加
降低

地下水/河流污染

增加
减少

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:

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:

中性/平衡

长期回报:

非常积极

6.5 技术采用

  • > 50%
注释:

66% of land user families have adopted the Technology with external material support
30% of all farmers approached by the project (about 400 out of 1,200 land users) have built these check dams. Seeds, tools and credits were provided as incentives; the reasons for implementation included both the attraction of the incentives and perceived ecological benefits in terms of rehabilitation of degraded areas.

34% of land user families have adopted the Technology without any external material support

There is a strong trend towards spontaneous adoption of the Technology

6.7 该技术的优点/长处/机会

编制者或其他关键资源人员认为的长处/优势/机会
Facilitated land management: area is no longer divided by gullies
Retards runoff speed: decreases erosion
Accumulation of fertile earth above the check dams, possibility of growing crops on ‘terraces’ between the structures
Increased soil moisture

6.8 技术的弱点/缺点/风险及其克服方法

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 check dams used alone as SWC measure may not be adequate to withstand concentrated runoff It is important to combine this technology with other SWC practices (e.g. retention ditches on slopes at both sides of gully, live fences, etc).
Only likely to be applied where land use rights are guaranteed.
Labour intensive.

7. 参考和链接

7.1 信息的方法/来源

  • 实地考察、实地调查
  • 与土地使用者的访谈
(现场)数据是什么时候汇编的?:

01/02/2004

7.2 参考可用出版物

标题、作者、年份、ISBN:

Gurdiel G . La construcción de diques. Tierra Fresca, Simas-Enlace, Managua. 1993.

标题、作者、年份、ISBN:

Guía Técnica de Conservación de Suelos y Agua. PASOLAC, Managua. 2000.

标题、作者、年份、ISBN:

LUPE . Manual Práctico de Manejo de Suelos en Laderas. Secretaría de Recursos Naturales, Tegucigalpa, Honduras. 1994.

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