Recently stabilised dike with old rice bags and Pandanus, next to an irrigation channel and an eroding sand road. (Stefan Graf)

Stabilisation of irrigation channels in sandy soils with old rice bags and Pandanus plants (柬埔寨)

បច្ចេកទេសដាក់បាវខ្សាច់ និងដាំដើមរំចេកតាមភ្លឺស្រែជាទំនប់ទប់ការហូរច្រោះ (Khmer)

描述

In sandy areas, old rice bags are filled with sand and piled up as dikes bordering irrigation channels, and Pandanus plants are used to stabilize them on the long term.

The paddy fields are surrounded by dikes and fed by local temporary streams and irrigation channels, as well as by rain. In sandy soils the dikes around the irrigation channels and fields cannot hold the water due to erosion. Old rice bags are filled with sand and piled up to form stable dikes on the short term, and Pandanus suckers are planted every 0.5 – 1 m to ensure a stability on the long term due to the root system.

The purpose of the dikes, stabilized for short and long term, is to ensure the flow of water to the paddy fields by reducing the riverbank erosion. It also helps to keep the water in the paddy fields. The Pandanus can be used to make mats and baskets, although this use diminishes due to the low cost of plastic. After a few years, the Pandanus on the dike is tall and spiky enough to fence off cattle and protect the rice from grazing.

To stabilize 50 m of dike, around 100 old rice bags are filled with sand and piled up on a height of 2 bags. Pandanus suckers are planted on the water side, between the bags, and sand is used to cover the plants and bags. Poles and sticks are used to stabilize the bags and plants until the root system is established. This is done in the beginning of the rainy season to ensure the growth of the sucker. In the first year, after each rain the eroded sand has to be added back to the dike. After the establishment phase, from the second year on, the Pandanus have to be cut back as they grow quickly and can grow tall.

The analysed area is flat (slope < 2%), with a tropical climate (dry season from November to May and wet season from June to October), and the soils are mostly sandy or loamy. The soil has a low fertility, contains little organic matter, and acidifies. The area has been deforested a long time ago, and the groundwater table is rather high (1-2 m during the dry season, on the surface during wet season).
Due to climate change, farmers notice more erratic rainfall, temperature rises and more recurrent droughts. Rice is the predominant crop grown in the area, since it serves as staple food (mix subsistence and commercial activities). Cattle are usually grazing on the fields after the harvest, without much control. Thus the cattle grazes too often and too much on the same spot, leading to degradation.
The increasing migration rate (the young generation leaves the villages to work in the cities, garment industry or abroad) results in a decrease of available labour force in the area which has detrimental effects on the agricultural activities. Furthermore, the civil war in the 1970s (Khmer Rouge) led to the loss of agricultural knowledge. Several NGOs are trying to re-establish the knowledge.

地点

地点: Chrey Bak/Rolea Pha’ear, Kampong Chhnang, 柬埔寨

分析的技术场所数量:

选定地点的地理参考
  • 104.5907, 12.11291

技术传播: 均匀地分布在一个区域 (approx. 1-10 平方千米)

在永久保护区?:

实施日期: 50多年前(传统)

介绍类型
Pandanus suckers growing between rice bags (Stefan Graf)

技术分类

主要目的
  • 改良生产
  • 减少、预防、恢复土地退化
  • 保护生态系统
  • 结合其他技术保护流域/下游区域
  • 保持/提高生物多样性
  • 降低灾害风险
  • 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
土地利用

  • 农田
    • 一年一作: 谷类 - 水稻(湿地)
    每年的生长季节数: 1
  • 水道、水体、湿地 -

供水
  • 雨养
  • 混合雨水灌溉
  • 充分灌溉

土地退化相关的目的
  • 防止土地退化
  • 减少土地退化
  • 修复/恢复严重退化的土地
  • 适应土地退化
  • 不适用
解决的退化问题
  • 土壤水蚀 - Wr:河岸侵蚀
  • 水质恶化 - Ha:干旱化
SLM组
  • 灌溉管理(包括供水、排水)
  • 引水和排水
  • 地表水管理(泉、河、湖、海)
SLM措施
  • 植物措施 - V1:乔木和灌木覆盖层
  • 结构措施 - S3:分级沟渠、渠道、水道

技术图纸

技术规范
Next to a road, (left) there is an irrigation channel in sandy soil. To prevent the little dam next to the rice field (right) from eroding, old rice bags are filled with sand and piled up. Between the rice bags, Pandanus suckers are planted. Sometimes they are also used to stabilise roadsides (not shown in this picture).
Kampong Chhnang
Date: 2014

Technical knowledge required for field staff / advisors: low
Technical knowledge required for land users: low
Main technical functions: stabilisation of soil (eg by tree roots against land slides), water harvesting / increase water supply, sediment retention / trapping, sediment harvesting

Vegetative measure: On dikes, allong irrigation channels
Vegetative material: T : trees / shrubs
Vertical interval within rows / strips / blocks (m): 0.5 - 1 m
Vegetative measure: Vegetative material: T : trees / shrubs
Trees/ shrubs species: Pandanus grown from suckers

Bund/ bank: graded
Height of bunds/banks/others (m): 0.3
Width of bunds/banks/others (m): 0.75

Construction material (other): Sand and sandbags
Vegetation is used for stabilisation of structures.
Author: Stefan Graf, Switzerland

技术建立与维护:活动、投入和费用

投入和成本的计算
  • 计算的成本为:
  • 成本计算使用的货币:Riels
  • 汇率(换算为美元):1 美元 = 4000.0 Riels
  • 雇用劳工的每日平均工资成本:5.00
影响成本的最重要因素
The labour is the most costly part in this technology. Through the use of old rice bags filled with sand the costs are already reduced.
技术建立活动
  1. Fill the old rice bags with sand, pile them up, stabilize with sticks and add more sand after each rain, till the root system of the Pandanus plants have established (1 year) (时间/频率: Beginning of wet season (Jun/Jul))
  2. Plant the Pandanus suckers between the bags (时间/频率: beginning of wet season (June/July))
技术建立的投入和成本
对投入进行具体说明 单位 数量 单位成本 (Riels) 每项投入的总成本 (Riels) 土地使用者承担的成本%
肥料和杀菌剂
Construction of biodigester 1.0 400.0 400.0 50.0
技术建立所需总成本 400.0
技术建立总成本,美元 0.1
技术维护活动
  1. Maintain the dikes (时间/频率: every rainy season)
  2. Cut back the Pandanus plants (时间/频率: Once a year, before planting rice)
技术维护的投入和成本
对投入进行具体说明 单位 数量 单位成本 (Riels) 每项投入的总成本 (Riels) 土地使用者承担的成本%
劳动力
labour 1.0 121.5 121.5 100.0
技术维护所需总成本 121.5
技术维护总成本,美元 0.03

自然环境

年平均降雨量
  • < 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
  • 潮湿的
  • 半湿润
  • 半干旱
  • 干旱
关于气候的规范
1486.45 mm 2013 in Kampong Chhnang
Thermal climate class: tropics. 27° to 35°C
斜坡
  • 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
海拔
  • 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.
......应用的技术
  • 凸形情况
  • 凹陷情况
  • 不相关
土壤深度
  • 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)
  • 细粒/重质(粘土)
土壤质地(地表以下>20厘米)
  • 粗粒/轻(砂质)
  • 中粒(壤土、粉土)
  • 细粒/重质(粘土)
表土有机质含量
  • 高(>3%)
  • 中(1-3%)
  • 低(<1%)
地下水位
  • 表面上
  • < 5米
  • 5-50米
  • > 50米
地表水的可用性
  • 过量
  • 中等
  • 匮乏/没有
水质(未处理)
  • 良好饮用水
  • 不良饮用水(需要处理)
  • 仅供农业使用(灌溉)
  • 不可用
水质请参考:
盐度是个问题吗?

洪水发生
物种多样性
  • 中等
栖息地多样性
  • 中等

应用该技术的土地使用者的特征

市场定位
  • 生计(自给)
  • 混合(生计/商业)
  • 商业/市场
非农收入
  • 低于全部收入的10%
  • 收入的10-50%
  • > 收入的50%
相对财富水平
  • 非常贫瘠
  • 贫瘠
  • 平均水平
  • 丰富
  • 非常丰富
机械化水平
  • 手工作业
  • 畜力牵引
  • 机械化/电动
定栖或游牧
  • 定栖的
  • 半游牧的
  • 游牧的
个人或集体
  • 个人/家庭
  • 团体/社区
  • 合作社
  • 员工(公司、政府)
性别
  • 女人
  • 男人
年龄
  • 儿童
  • 青年人
  • 中年人
  • 老年人
每户使用面积
  • < 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
规模
  • 小规模的
  • 中等规模的
  • 大规模的
土地所有权
  • 公司
  • 社区/村庄
  • 团体
  • 个人,未命名
  • 个人,有命名
土地使用权
  • 自由进入(无组织)
  • 社区(有组织)
  • 租赁
  • 个人
用水权
  • 自由进入(无组织)
  • 社区(有组织)
  • 租赁
  • 个人
进入服务和基础设施的通道
健康

贫瘠
教育

贫瘠
技术援助

贫瘠
就业(例如非农)

贫瘠
市场

贫瘠
能源

贫瘠
道路和交通

贫瘠
饮用水和卫生设施

贫瘠
金融服务

贫瘠

影响

社会经济影响
作物生产
降低
增加


Dried residues are put in the garden (cucumber, pumpkin, watermelon) which increases nutrient availability.

饲料生产
降低
增加

生产故障风险
增加
降低

生产区域(耕种/使用中的新土地)
降低
增加

能源生产(例如水力发电、生物发电)
降低
增加


Before the installation of the biogas system, the land user bought firewood.

农业投入费用
增加
降低


He saves 50 $ on chemical fertilizer per year.

农业收入
降低
增加

收入来源的多样性
降低
增加

工作量
增加
降低

社会文化影响
食品安全/自给自足
减少
改良

健康状况
恶化
改良


No smoke from open fire.

contribution to human well-being
decreased
increased


On the long term livelihood is improved, because he saves over 60 $ per year in firewood and battery charging for light, as well as 50 $ for chemical fertilizer.

生态影响
水量
降低
增加

水质
降低
增加


Pollution of groundwater due to washing out of nutrients.

土壤水分
降低
增加

土壤流失
增加
降低

土壤有机物/地下C
降低
增加


Most of the carbon is transformed into methane, not available as organic matter.

害虫/疾病控制
降低
增加

Reduced weed seeds
decreased
increased


Compost usually not completely decomposed, as well as raw manure, contain lots of weed seeds.

场外影响
地下水/河流污染
增加
减少


Sludge is left to dry outside, nutrients washed out into groundwater. Not measurable.

成本效益分析

与技术建立成本相比的效益
短期回报
非常消极
非常积极

长期回报
非常消极
非常积极

与技术维护成本相比的效益
短期回报
非常消极
非常积极

长期回报
非常消极
非常积极

Difficult question for farmers.

气候变化

渐变气候
年温度 增加

非常不好
非常好
气候有关的极端情况(灾害)
局地暴雨

非常不好
非常好
答案:未知
局地风暴

非常不好
非常好
干旱

非常不好
非常好
比较和缓的(河道)洪水

非常不好
非常好
答案:未知
其他气候相关的后果
缩短生长期

非常不好
非常好

采用和适应

采用该技术的地区内土地使用者的百分比
  • 单例/实验
  • 1-10%
  • 11-50%
  • > 50%
在所有采用这种技术的人当中,有多少人在没有获得物质奖励的情况下采用了这种技术?
  • 0-10%
  • 11-50%
  • 51-90%
  • 91-100%
最近是否对该技术进行了修改以适应不断变化的条件?
什么样的变化条件?
  • 气候变化/极端气候
  • 不断变化的市场
  • 劳动力可用性(例如,由于迁移)

结论和吸取的教训

长处: 土地使用者的观点
  • The Pandanus leaves are used for baskets and mats.
  • The water is stored in the rice fields. Without stabilisation, the berms would not hold any water at all in sandy conditions.
  • Cattle is fenced off the rice fields through tall and thick (old) Pandanus plants growing on the dikes.
  • The irrigation channels are not eroded, water keeps flowing
长处: 编制者或其他关键资源人员的观点
弱点/缺点/风险: 土地使用者的观点如何克服
  • The Pandanus grow too quickly and too tall, and require workload which is not available. Select slow growing species or individuals.
  • Rodents use the Pandanus as niches. Protect natural predators (snakes), or hunt/trap the rodents.
弱点/缺点/风险: 编制者或其他关键资源人员的观点如何克服
  • the plastic from the rice bags disintegrates with time and causes river pollution. Use organic material (e.g. rice bags) to stabilize the dike for the first year.

参考文献

编制者
  • Stefan Graf
Editors
审查者
  • Deborah Niggli
  • Alexandra Gavilano
  • Rima Mekdaschi Studer
实施日期: Nov. 6, 2014
上次更新: Feb. 7, 2024
资源人
WOCAT数据库中的完整描述
链接的SLM数据
文件编制者
机构 项目
主要参考文献
  • NBP National Biodigester Program: www.nbp.org.kh
  • Lam et al. 2009. Domestic Biogas Compact Course. University of Oldenburg.: http://www.nbp.org.kh/publication/study_report/2_domestic_biogas%20.pdf
  • Gurung. 2009. Review of Literature on Effects of Slurry Use on Crop production. The Biogas Support Program:
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