1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of project which facilitated the documentation/ evaluation of the Technology (if relevant)

Scaling-up SLM practices by smallholder farmers (IFAD)

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

Royal University of Agriculture (RUA) - Cambodia

1.3 Conditions regarding the use of data documented through WOCAT

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

1.4 Declaration on sustainability of the described Technology

Is the Technology described here problematic with regard to land degradation, so that it cannot be declared a sustainable land management technology?

No

2.1 Short description of the Technology

Definition of the Technology:

Biodigester slurry sourced from cow manure is used as an important natural fertilizer for the cultivation of crops. It is a form of organic fertilizer that is thoroughly decomposed, does not have an awful smell, or contain living weed seeds, fungi and other viruses. It can also be used immediately after the slurry flows out of the biodigester tank. Such fertilizer helps to improve the soil quality in the long-term due to the rich organic matter that it contains which slowly decomposes to plant nutrients.

2.2 Detailed description of the Technology

Description:

There are many kinds of biodigesters and the one used in this technology is a 5000 liter plastic cylinder. It was installed by placing part of the tank into the ground and setting up an inlet-outlet pipe as well as a gas pipe system. The whole installation process takes around a day to complete. In order to produce gas initially the biodigester needs about 120 buckets (around 2000 kg) of fresh cow manure and 120 buckets (1200 liters) of water, which then needs to be kept for one week so that it can produce gas and slurry as fertilizer. After that the farmer has to add one bucket (around 20 kg) of fresh cow manure and one bucket (20 liters) of water every day in order to maintain the continuous production of gas and slurry. As a result, the farmer’s family has gas from the biodigester which provides sufficient energy for cooking. In this way they are able to save time which is otherwise spent collecting fuel-wood and it reduces their firewood consumption by around 2190 kg per year. The fresh cow manure for the biodigester should be free from rubbish and not contain small gravel because this blocks the inlet /outlet of the biodigester tank.

In addition, to be able to use the gas for cooking and lighting, the farmer also has the opportunity of using the slurry from the biodigester as fertilizer for all kinds of crops, including bitter gourds, eggplants, mangos, yard long beans, rice, bamboo shoots and other supplementary crops. The slurry from the biodigester can be applied as fertilizer either in a liquid, a semi-dry or a dry form. The slurry can be applied to the crops directly or compost can be made by mixing it with other degradable materials such as woody herb, rice straw and other green leaves. This practice will increase the quantity of the fertilizer because the slurry from bioidigester helps to accelerate the decomposition process and it also produces a higher quality compost.

The slurry from biodigester improves soil aggregates and fertility for a longer period than chemical fertilizers. The slurry contains a lot of nutrients specially nitrogen, phosphorus and potassium that are necessary for plants, and it does not have an awful smell, or contain weed seeds and parasites. The nutrients are in a chemical form which can easily be absorbed by plants, and it contains vitamin B12 which stimulates the growth of earth worms. The use of slurry enables the growth of various microorganisms and besides earth worms, other useful animals such as frogs and soil-insects, thereby maintaining a natural balance of the environment. The fertilizer enhances the growth of crops, builds resistance to disease, and does not affect the soil and human health. For poorer quality soil, the slurry or compost improves both the physical and biological conditions of the soil. It improves the nutrient content including macronutrients and micronutrients, and also helps to keep soil aggregates and moisture.

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

2.6 Date of implementation

Indicate year of implementation:

2016

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through projects/ external interventions

Comments (type of project, etc.):

National Biodigester Programme

3.1 Main purpose(s) of the Technology

• improve production
• reduce, prevent, restore land degradation
• conserve ecosystem
• preserve/ improve biodiversity
• mitigate climate change and its impacts
• create beneficial economic impact

3.2 Current land use type(s) where the Technology is applied

Land use mixed within the same land unit:

Yes

Specify mixed land use (crops/ grazing/ trees):

• Agroforestry

Comments:

Main crops (cash and food crops): Rice, sugar cane, banana, eggplant, bitter gourd, yard long bean, mango and other vegetable.
Raising of 19 cows to supply manure for the biodigester and also around 100 chicken

3.3 Has land use changed due to the implementation of the Technology?

Has land use changed due to the implementation of the Technology?

• Yes (Please fill out the questions below with regard to the land use before implementation of the Technology)

Comments:

This land was previously degraded forest land.

3.4 Water supply

Water supply for the land on which the Technology is applied:

• mixed rainfed-irrigated

Comments:

For irrigating the crops the farmer uses groundwater from the well .

3.5 SLM group to which the Technology belongs

• integrated crop-livestock management
• energy efficiency technologies

3.6 SLM measures comprising the Technology

3.7 Main types of land degradation addressed by the Technology

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• prevent land degradation
• reduce land degradation

4.1 Technical drawing of the Technology

4.2 General information regarding the calculation of inputs and costs

Specify how costs and inputs were calculated:

• per Technology unit

other/ national currency (specify):

Riel

If relevant, indicate exchange rate from USD to local currency (e.g. 1 USD = 79.9 Brazilian Real): 1 USD =:

4000.0

4.3 Establishment activities

	Activity	Timing (season)
1.	Dig soil	May
2.	Put biodigester	May
3.	Prepare pipe system	May
4.	Install	May
5.	Add cow manure	May

4.4 Costs and inputs needed for establishment

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% of costs borne by land users
Equipment	Biodigester	set	1.0	4000000.0	4000000.0	20.0
Total costs for establishment of the Technology					4000000.0
Total costs for establishment of the Technology in USD					1000.0

If you are unable to break down the costs in the table above, give an estimation of the total costs of establishing the Technology:

4000000.0

If land user bore less than 100% of costs, indicate who covered the remaining costs:

Support from National Biodigester Programme (NBP)

Comments:

80% of the total cost was subsidised by the NBP.

4.5 Maintenance/ recurrent activities

	Activity	Timing/ frequency
1.	Clean drainage pipes	every day
2.	Putting cow manure	every day

4.6 Costs and inputs needed for maintenance/ recurrent activities (per year)

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% of costs borne by land users
Labour	Cleaning by themself	Hour	30.42	3124.0	95032.08	100.0
Fertilizers and biocides	Cow manure	Kg	20.0	1200.0	24000.0	100.0
Fertilizers and biocides	Water	Liter	20.0	200.0	4000.0	100.0
Total costs for maintenance of the Technology					123032.08
Total costs for maintenance of the Technology in USD					30.76

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The cost of the plastic tank and the enough cows to producing sufficient slurry for the manure production.

5.1 Climate

5.2 Topography

Indicate if the Technology is specifically applied in:

• not relevant

5.3 Soils

If available, attach full soil description or specify the available information, e.g. soil type, soil PH/ acidity, Cation Exchange Capacity, nitrogen, salinity etc.

pH: 5.5

5.4 Water availability and quality

Is water salinity a problem?

No

Is flooding of the area occurring?

No

Comments and further specifications on water quality and quantity:

Groundwater from well is used for irrigation and ensures supply for the whole year.

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

5.7 Average area of land used by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• individual, titled

Land use rights:

• individual

Water use rights:

• individual

5.9 Access to services and infrastructure

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Water cycle/ runoff

Soil

Biodiversity: vegetation, animals

6.2 Off-site impacts the Technology has shown

6.3 Exposure and sensitivity of the Technology to gradual climate change and climate-related extremes/ disasters (as perceived by land users)

Gradual climate change

Gradual climate change

	Season	increase or decrease	How does the Technology cope with it?
annual temperature		increase	moderately
seasonal temperature	wet/ rainy season	increase	moderately
annual rainfall		increase	moderately
seasonal rainfall	wet/ rainy season	increase	moderately

Climate-related extremes (disasters)

Climatological disasters

	How does the Technology cope with it?
drought	well

Biological disasters

	How does the Technology cope with it?
epidemic diseases	moderately
insect/ worm infestation	moderately

Comments:

When watjer is hotter soils keep moisture better and does not dry very fast.

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

Comments:

No money was needed to repair the biodigester system untill now.

6.5 Adoption of the Technology

• 1-10%

If available, quantify (no. of households and/ or area covered):

Six households have been supported to get the biodigester by the NBP.

Of all those who have adopted the Technology, how many did so spontaneously, i.e. without receiving any material incentives/ payments?

• 0-10%

Comments:

Many farmers want to install the biodigester, but has difficulty with the expenses.

6.6 Adaptation

Has the Technology been modified recently to adapt to changing conditions?

No

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the land user’s view
Manufacture fertilizer by himself
Can be applied directly to the crop which not results in its putrefy, unlike fresh cow manure which can lead to the putrescence of crops and the growth of a lot of grass.
Saving of 2190 kg of firewood per year.

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Helps to improve the soil quality.
Reduces negative environmental effects.
Reduces daily costs.

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

Weaknesses/ disadvantages/ risks in the land user’s view	How can they be overcome?
A biodigester is expensive	National biodigester programme to support

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
A biodigester is expensive	Need a supporting fund from relevant institutions.
Need of enough cow manure	Promote livestock raising, especially cows.

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

National Biodigester Programme (2013): Farmers Handbook on Management and Use of waste biodigester. Public on January 10th (in khmer)

Available from where? Costs?

Ministry of Agriculture, Forestry and Fisheries

7.3 Links to relevant online information

Title/ description:

National Biodigester Program.(2015). National Biodigester Program in CAMBODIA.Ministry of Agriculture, Forestry and Fisheries (in Khmer).retrieve 15/01/2018 from

URL:

www.nbp.org.kh

Title/ description:

Savbory.O.(2014). Mistry announce farmer to use biodigester for get profit.Radio Free Asia (in Khmer). retrieved on 15/01/2018 from

URL:

www.rfa.org/khmer/news/environment/bio-mass-oven-03062014034222.html

Title/ description:

Mansvelt,.R.&Sras,.P.&Pino,.M.(2012).Biodigester User Survey 2012.National Biodigester Programme.retrieved 15/01/2018 from

URL:

https://www.google.com/search?q=Biogas+user+survey+-+Cambodia+2009-2010+&ie=utf-8&oe=utf-8&client=firefox-b-ab

Title/ description:

Mansvelt.R.(2011).Biodigester User Survey 2009-2010. National Biodigester Programme.retrieved 15/01/2018 from

URL:

https://www.google.com/search?q=Biogas+user+survey+-+Cambodia+2009-2010+&ie=utf-8&oe=utf-8&client=firefox-b-ab