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

1.3 关于使用通过WOCAT记录的数据的条件

（现场）数据是什么时候汇编的？:

05/08/2014

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:

Small-scale biogas systems fed with cow manure and water are implemented in order to supply the household with energy for cooking and lighting, as well as to produce fertilizer.

2.2 技术的详细说明

说明:

In this case-study, a small-scale biogas system was introduced in order to generate both energy for home consumption and fertilizer. Small-scale biogas systems are implemented in different parts of the world, however the layout thereof varies considerably.
The model used in this case-study consists of different components (cf. technical drawing). First, there is an inlet where the land user puts cow manure mixed with water. On the bottom of the inlet, there is a board which closes the access to the bio-digester situated beneath the inlet. The board can be opened manually by pulling a string. Once the board is open, the fluid components go through a pipe which leads to the bio-digester. In the bio-digester, bacteria transform the organic matter into biogas (mainly methane and CO2) and slurry. At the other end of the digester, there is another pipe (outlet). The outlet is lower than the inlet, and due to the difference in pressure, the slurry is pushed out of the digester. The slurry is dried and applied to the fields two to three times a year with the help of an ox cart. It has similar effects on the plant growth as chemical fertilizer as it does not build up the soil organic matter as much as compost. The biogas, however, is pushed to the pipe situated on top of the digester and can be utilized for domestic uses. The gas is used for cooking and lighting.

The use of biogas allows reducing the expenses on charging batteries for the lighting, as well as reducing the firewood use (usually from deforestation) for cooking. The slurry reduces the expenses on chemical fertilizer in the fields and has the advantage of killing the weed and rice seeds present in the manure and crop residues.

For building the biogas system, there is governmental and NGO support. These two actors finance half of the construction costs. The other half is paid by the land user. Building a biogas system is quite costly, with about 400 $, and not all of the land users in the area can afford paying 50% of its price. However, the costs borne by the land user are paid off within a few years due to reduced expenses on firewood, chemical fertilizer, and charging batteries. The construction itself was undertaken by local companies.
The costs are paid off within a few years due to the reduced expenses on firewood, chemical fertilizer and battery charging.

The analysed area is flat (slope < 2%), tropic (dry and wet season), and the soils are mostly sandy or loamy. The soils contain little organic matter (low soil fertility, acidification, small amount of cattle, area has been deforested a long time ago) and the groundwater table is rather high (1-3 m during the dry season, on the surface during wet season).
Due to climate change, the rainfalls are more erratic, temperatures rise and droughts are more recurrent. Rice is the predominant crop grown in the area, since it serves as staple food (mix subsistence and commercial activities). Rice is often grown in monocultures and harvested once a year. Once the rice is harvested (dry season), the cattle are released to the paddy fields. The cattle is often replaced by hand tractors, which effects the production of manure but allows a higher amount of crop residues on the fields.
As an addition to rice, most land users grow vegetable and fruits in small home gardens (subsistence) and complement their income by producing handicrafts or through off farm income / remittances from family members working in other places. 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 which different NGOs try to re-establish.

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

2.6 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

注释（项目类型等）:

LWS (a Dutch NGO) in joint efforts with specialists from the National Biodigester Program NBP. Implementation in 2012

3.1 该技术的主要目的

• 改良生产
• 创造有益的经济影响

3.2 应用该技术的当前土地利用类型

注释:

Major land use problems (compiler’s opinion): Lack of organic matter, lack of water retention in soil, irregularity of rainfall, low soil fertility (sandy soil), monocultures, bare soil during dry season, ploughing.
Major land use problems (land users’ perception): Low soil fertility, lack of water.
Livestock is grazing on crop residues
Constraints of settlement / urban
Constraints of infrastructure network (roads, railways, pipe lines, power lines)

3.3 有关土地利用的更多信息

每年的生长季节数:

• 1

具体说明:

Longest growing period in days: 210, Longest growing period from month to month: June-December

3.4 该技术所属的SLM组

• 节能技术

3.5 技术传播

具体说明该技术的分布:

• 均匀地分布在一个区域

如果该技术均匀地分布在一个区域上，请注明覆盖的大致区域。:

• 0.1-1 平方千米

注释:

There are only 4 households in this village which apply the technology (lack of money and/or cattle). However, similar Technologies are introduced in other provinces – yet it is difficult to estimate the area covered. Estimation for this village.

3.6 包含该技术的可持续土地管理措施

注释:

Main measures: management measures
Secondary measures: structural measures

3.7 该技术强调的主要土地退化类型

注释:

Main causes of degradation: soil management (Ploughing, soil is left bare for several weeks), crop management (annual, perennial, tree/shrub) (Rice monoculture (rice as staple crop)), change of seasonal rainfall (More erratic beginning of wet season), droughts (On dry soil, rice cannot be planted and if already planted, rice cannot grow), labour availability (High migration rates from the villages to garment industry, cities or abroad, influence agricultural activities (e.g. broadcasting instead of transplanting of rice seedlings)), education, access to knowledge and support services (Khmer Rouge regime in the 1970s, a lot of knowledge got lost)
Secondary causes of degradation: over-exploitation of vegetation for domestic use (Rice straw is removed for different domestic uses (cattle, mushroom cultivation, etc.)), overgrazing (Cattle eats rice straw left after harvest, less organic matter on the field, grazing is not managed), change in temperature (More hot days), Heavy / extreme rainfall (intensity/amounts), land tenure (Some incidents of land grabbing, land use rights not clear, corruption), poverty / wealth

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

4.1 该技术的技术图纸

4.2 技术规范/技术图纸说明

Biodigester. Inlet: top left; gas outlet: top centre; digestion chambre: centre; and outlet: right. For the comlete building instructions contact the NBP.
Technical knowledge required for field staff / advisors: high (The most challenging part is the construction of the construction of the Biodigester.)
Technical knowledge required for land users: low
Main technical functions: increase in nutrient availability (supply, recycling,…)
Secondary technical functions: increase in organic matter

Structural measure: Biodigester. Round shape. Tiles and concrete.
Width of ditches/pits/dams (m): 4 m^3
Structural measure: Connecting pipes made of plastic
Construction material (concrete): Tiles are covered in concrete.
Construction material (other): The most challenging part is the construction of the Biodigester.
Other type of management: Change of energy supply system for home consumption.

4.3 有关投入和成本计算的一般信息

其它/国家货币（具体说明）:

Riel

注明美元与当地货币的汇率(如相关):1美元=:

4000.0

4.4 技术建立活动

	活动	措施类型	时间
1.	Construction of the biodigester by external experts. The land user did not help with the construction, he only paid 200 US$. The other 200 US$ were paid by the National Biodigester Program.	结构性的	Dry season, when water table is low.

4.5 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%
施工材料	Construction of biodigester		1.0	400.0	400.0	50.0
技术建立所需总成本					400.0

4.6 维护/经常性活动

	活动	措施类型	时间/频率
1.	Add manure and water to the inlet	管理	once per day all year round
2.	Collect residuals from biodigester, spread it out and let it dry, and finally put it on the field.	管理	3 times/year

4.7 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		1.0	121.5	121.5	100.0
技术维护所需总成本					121.5

注释:

Machinery/ tools: Cart to bring residues from the biodigester onto the fields.

The costs were calculated for 1 biodigester with a capacity of 4 m3.

4.8 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 costly part of this Technology is the construction of the biodigester. Once the system is installed, the costs borne by the land user are low. Also, the land user can save money since he doesn’t need to buy firewood any more.

5.1 气候

5.2 地形

5.3 土壤

5.4 水资源可用性和质量

关于水质和水量的注释和进一步规范:

Ground water tabel and availability of surface water data during dry seasons. People use water for drinking after filtering or boiling.

5.5 生物多样性

关于生物多样性的注释和进一步规范:

Only degraded forests are in the area.

5.6 应用该技术的土地使用者的特征

说明土地使用者的其他有关特征:

Land users applying the Technology are mainly Leaders / privileged
Population density: 10-50 persons/km2
Annual population growth: 0.5% - 1%
Off-farm income specification: Handicraft, remittances and factory work.

5.7 应用该技术的土地使用者拥有或租用的平均土地面积

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
• 个人，未命名

土地使用权:

• 社区（有组织）
• 个人

用水权:

• 自由进入（无组织）

注释:

Land ownership is very complex. Most of the land belongs officially to the government, yet many land users hold a paper confirming they applied for a land title – but de iure, this paper is worthless.

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

收入和成本

社会文化影响

生态影响

水循环/径流

土壤

其它生态影响

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）

渐变气候

渐变气候

	季节	气候变化/极端天气的类型	该技术是如何应对的？
年温度		增加	好

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	好
局地风暴	好

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	不好

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	好

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）？

6.5 技术采用

• 大于 50%

如若可行，进行量化（住户数量和/或覆盖面积）:

100% or 4 land user families

注释:

100% of land user families have adopted the Technology with external material support
4 land user families have adopted the Technology with external material support
The farmers can ask the National Biodigester Program for subsidies, but need to pay half of it on their own. As the farmers often lack money and need at least 3 - 4 heads of cattle to produce enough manure while they switch more and more to hand tractors, not many farmers are building new biogas digesters.

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
Fertilizer production (sludge).
Saves money and time on the cooking fuel (previously wood) and electricity (charging batteries) for the light.
No weed seeds in the sludge compared to compost and raw manure if used as fertilizer.

编制者或其他关键资源人员认为的长处/优势/机会
Less deforestation for firewood.

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 residue does not improve the soil as much as compost.	Make compost in addition to biogas to enhance the soil organic matter.
The building costs are prohibitive	Increase subsidies from state or NGOs.
At least 3-4 heads of cattle or 4-5 pigs have to be kept to produce enough manure.	Diversify production with different animals.
Work has to be done each day to produce biogas.

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？
Overgrazing could become a problem as more cattle needs to be kept.	Add slurry as a liquid fertilizer
Part of nitrogen is volatilized during the drying of the sludge.

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:

NBP National Biodigester Program

可以从哪里获得?成本如何?

www.nbp.org.kh

标题、作者、年份、ISBN:

Lam et al. 2009. Domestic Biogas Compact Course. University of Oldenburg.

可以从哪里获得?成本如何?

http://www.nbp.org.kh/publication/study_report/2_domestic_biogas%20.pdf

标题、作者、年份、ISBN:

Gurung. 2009. Review of Literature on Effects of Slurry Use on Crop production. The Biogas Support Program