技术

Unexpected flood risk control in village [尼泊尔]

Bhelbadi Niyantran

technologies_1590 - 尼泊尔

完整性: 71%

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:

Koirala Pratiksha

尼泊尔

Gautam Bibhu

尼泊尔

Mulmi Anjuli

尼泊尔

有助于对技术进行记录/评估的机构名称(如相关)
Kathmandu University (KU) - 尼泊尔

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:

It is a technology used to control and reduce the effects of downstream flood by physical interventions like construction of spillway, ditch and stone dam on the wall of ditch.

2.2 技术的详细说明

说明:

Hilly areas are prone to flash flood that occur with little warning. During rainy season, level of water rises in the stream due to which land mass field of around area was degraded. This technology is used to control the land mass and water flowing from upper region to the lower region of the hill. The natural stream was modified to deep and more sloppy. And surrounding walls were made by piling up stones dams and tighten them by metal wires. These dams decrease the slope gradient and reduce the velocity of water flow and promote the deposition of eroded materials.

Purpose of the Technology: There was no problem of landslide and downstream flood before. But after the road construction, soil became loose resulting in the occurrence of downstream flood. It caused massive destruction of agricultural fields and disturbed settlement areas. Also, stone and gravel during landslide and stream flood used to be deposited and block the flow of the water. So land user invented by this technology to control and reduce the effects of downstream flood.

Establishment / maintenance activities and inputs: Land users and other villagers took the initiative to carry out the technology. Stones were abundantly found in the stream that were utilized to make the dams on lining the stream. Dozer was used to deepen the stream and increase the slope of stream. Stones were piled up and tied by iron wires on the bank of stream by local farmers themselves with their own investment.

Natural / human environment: The area where this technology has been used is a hilly area. Soil fertility in that area is low or medium which differs according to the place. Due to landslide and downstream flood, sand and gravel get deposited in the cropland, so its fertility is very low. No crops can be grown in there. This technology helps to control further degradation of land but could't help to restore natural quality of land.
This area is semi arid area. Due to the proper supply of water the area is prevented from drying. People living in that area are mainly farmers and depend on agriculture for livelihood. Also the area is developing more after the road construction. People are now being more aware about health, education and development.

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:

尼泊尔

区域/州/省:

Nepal

有关地点的进一步说明:

Kavre

具体说明该技术的分布:
  • 适用于特定场所/集中在较小区域
注释:

The area occupied by SLM technology is approximately 28 km2. It includes area occupied by conversation measures and the additional area protected by them.

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:
  • 通过土地使用者的创新
注释(项目类型等):

The problem of downstream flood was caused before two years after the construction of road. so technology was also developed before 2 years.

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

水道、水体、湿地

水道、水体、湿地

  • Waterway, ditch
注释:

Major land use problems (compiler’s opinion): Cropland destruction

Major land use problems (land users’ perception): Cropland destruction, vegetation destruction, decreased soil fertility.

Constraints of waterway/ditch (Ditch for the flow of water): Big stone which block the water ways.

Number of growing seasons per year: 3
Longest growing period in days: 150; Longest growing period from month to month: june-november; Second longest growing period in days: 90; Second longest growing period from month to month: march-june

3.5 该技术所属的SLM组

  • 地表水管理(泉、河、湖、海)

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

  • S3:分级沟渠、渠道、水道
  • S6:墙、障碍物、栅栏、围墙

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
  • Wo:场外劣化效应
注释:

Main causes of degradation: urbanisation and infrastructure development (Construction of road i.e infrastructure development), floods (Downstream flood during rainy season.), inputs and infrastructure: (roads, markets, distribution of water points, other, …) (Road construction)

Secondary causes of degradation: Heavy / extreme rainfall (intensity/amounts) (Heavy rainfall during rainy season cause downstream flooding.)

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
注释:

Secondary goals: mitigation / reduction of land degradation, rehabilitation / reclamation of denuded land

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):

This technical drawing shows the constructed dam and gully which allow proper flow of downstream flood.

Location: Chyamrangbes. Kavre

Technical knowledge required for land users: high

Technical knowledge required for labour: high (Through their experience to construct in a useful way.)

Main technical functions: control of concentrated runoff: drain / divert, reduction of slope angle

Secondary technical functions: control of dispersed runoff: retain / trap, improvement of surface structure (crusting, sealing)

Diversion ditch/ drainage
Vertical interval between structures (m): n'a
Spacing between structures (m): n'a
Depth of ditches/pits/dams (m): 2.13
Width of ditches/pits/dams (m): 3.2
Length of ditches/pits/dams (m): 1000
Height of bunds/banks/others (m): 1.6
Width of bunds/banks/others (m): 0.8
Length of bunds/banks/others (m): 1000

Construction material (earth): Soil excavate from the ditches is used to build bank.

Construction material (stone): the cut off ditch is lined with stones, embankment with stones.

Construction material (other): iron wire was used to bind the stone together.

Slope (which determines the spacing indicated above): 12%

作者:

Bibhu Gautam, KUGH,Kavre

4.2 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

4.3 技术建立活动

活动 时间(季度)
1. Land user increased the width and slope of existing ditch for easy flow of water. dry seasonm
2. Land user embanked the bank with stones on either side. dry season
3. Stones are bind together by wires in some places. 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 Increase the width and slope of ditch ha 1.0 941.17 941.17 100.0
技术建立所需总成本 941.17
技术建立总成本,美元 941.17
注释:

Duration of establishment phase: 2 month(s)

4.6 维护/经常性活动所需要的费用和投入(每年)

注释:

Machinery/ tools: dozer, Dozer

The above mentioned cost is not given per unit/hectar. It is the total cost used for that technology.

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 most determinate factor affecting the cost is land structure. Land contains loamy soil which made it difficult for construction of ditch.

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:

monsoon rain, dry winter

农业气候带
  • 半干旱

Thermal climate class: subtropics

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.
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:

Slopes on average: The average slope is about 15%.

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)
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 texture: Sandy and graveled land

Soil fertility is medium - low and varies according to soil texture

Soil drainage / infiltration is poor

Soil water storage capacity is low, soil is sandy and contains gravel. So it cannot store water

5.4 水资源可用性和质量

地下水位表:

表面上

地表水的可用性:

过量

水质(未处理):

不可用

关于水质和水量的注释和进一步规范:

Ground water table: Infiltration is very low. Water only flow on surface.

Availability of surface water: During rainy season excess water flow through the steam.

Water quality (untreated): Some portion water is used in agriculture

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:

Soil is very infertile. So it is poor in biodiversity.

5.6 应用该技术的土地使用者的特征

非农收入:
  • 低于全部收入的10%
相对财富水平:
  • 平均水平
  • 丰富
个人或集体:
  • 团体/社区
性别:
  • 女人
  • 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

Difference in the involvement of women and men: More male because women cannot do such type of heavy labor work.

Population density: 50-100 persons/km2

Annual population growth: 2% - 3%

(living standard is more than average).
(average life standard).

Off-farm income specification: Their land is protected from further degradation

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
土地使用权:
  • 社区(有组织)
注释:

The land where SLM technology is applied belongs to individual, but it land use right belongs to community.

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

生产故障风险

增加
降低
SLM之前的数量:

n/a

SLM之后的数量:

n/a

注释/具体说明:

protected the cropland from flood

社会文化影响

SLM/土地退化知识

减少
改良
SLM之前的数量:

n/a

SLM之后的数量:

n/a

注释/具体说明:

active participating people on land conservation.

生态影响

水循环/径流

地表径流

增加
降低
注释/具体说明:

water travel in fixed path

多余水的排放

减少
改良
注释/具体说明:

improved water way for passage of excess water

土壤

土壤流失

增加
降低
注释/具体说明:

soil loss due to flooding is reduced

6.2 该技术的场外影响已经显现

下游洪水

增加
减少
注释/具体说明:

the main benefits of this technology

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 不好
局地风暴 未知
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 不好
注释:

Dame can be made more tolerant again flash flood by using wire to tighten the stone walls or making the concrete wall.

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:

轻度消极

注释:

This technology is not a investment purpose. People used their own money to construct it.

6.5 技术采用

  • 单例/实验
如若可行,进行量化(住户数量和/或覆盖面积):

14 households in an area of 10 - 100 sq km (50 - 100 persons per sq km)

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%
注释:

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

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

Comments on acceptance with external material support: Iron wire was provided by Bagmati watershed.

There is a strong trend towards spontaneous adoption of the Technology

Comments on adoption trend: People have well accepted this technology.

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
Risk of downstream flood and landslide is reduced.

How can they be sustained / enhanced? If they had been more donation from government or any other projects, they would construct concrete or more flood resistance dams. As some parts are still unconstructed they would complete them with some more external support.
Agriculture land get protected so they can plant the crop without being at risk.
编制者或其他关键资源人员认为的长处/优势/机会
Proper water drainage system and water can get collected in the river following the fix path.

How can they be sustained / enhanced? Fodder plant could be grown on the stream banks which is now left and unused. This could be used to feed the animals and would also help to control flood and landslide.
It reduced the risk of further land degradation by downstream flood.

How can they be sustained / enhanced? Dams can be made more strong by making concrete walls

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?
N/A
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?
N/A N/A

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