Technologies

Cashew living fences [Cambodia]

ដំណំាចន្នីដំាជារបងរស់ (Khmer)

technologies_1643 - Cambodia

Completeness: 80%

1. معلومات عامة

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

Key resource person(s)

SLM specialist:
SLM specialist:

Khun Lean Hak

SOFDEC/LAREC, www.sofdec.org

Cambodia

SLM specialist:

Sreytouch Bin

SOFDEC

Cambodia

SLM specialist:

Pith Khonhel

LAREC

Cambodia

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)
Society for Community Development in Cambodia (SOFDEC) - Cambodia
Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)
Local Agricultural Research and Extension Centre (LAREC) - 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:

نعم

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?

لا

2. Description of the SLM Technology

2.1 Short description of the Technology

Definition of the Technology:

Living fences of cashew, reinforced with bamboo and/or barbed wire, are used to keep the cattle off the garden or the rice seedbed.

2.2 Detailed description of the Technology

Description:

Cashews (Anacardium occidentale) are fast growing, waterlogging tolerant tropical trees that can be used as living fences. The cashews act as fence posts, and are reinforced with bamboo poles and/or barbed wire. The living fences are used to either fence cattle into fields or fence them off, usually around the house. The fenced areas can be planted during the dry season. Without fences, the cattle are free roaming and use to destroy the crops.

Besides fencing the cattle, the purposes of cashew living fences are the production of nuts and fruits, fuel, and soil enhancer. The nuts are sold, but there is no market for the fruits, thus they are fed to cattle or let to rot. The wood is used to cook or to produce charcoal; the ash is added to the compost. The leaves are gathered as well and added to the compost.

Although cashews can stand waterlogged conditions, they prefer a well-drained soil. Thus a small berm is built up on the emplacement of the fence, and sown with cashew seeds spaced from 0.5 to 3 m. Cashews grow faster when directly sown than when transplanted. The spacing varies according to the farmers’ purpose. If a higher production of nuts is intended, the spacing is wider; if the fence is more important, the plants are grown closer. Cattle do not eat the leaves and branches, thus do not need protection from grazing. One year after sowing the cashews, the trees are tall enough to act as fence posts and support bamboo pole as well as barbed wire. The bamboo is either gathered from the wild or grown in the fields and home gardens. The bamboo is fixed to the living posts with natural fibers/vines or old clothes, and has to be replaced every two to three years to withstand cattle.

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 rainfalls, 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.

2.3 Photos of the Technology

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

بلد:

Cambodia

Region/ State/ Province:

Kampong Chhnang

Further specification of location:

Krang Liav, Rolea Pha-er

Specify the spread of the Technology:
  • evenly spread over an area
If precise area is not known, indicate approximate area covered:
  • < 0.1 km2 (10 ha)
Comments:

Around 15 farmers in this village use cashew living fences.

2.6 Date of implementation

If precise year is not known, indicate approximate date:
  • 10-50 years ago

2.7 Introduction of the Technology

Specify how the Technology was introduced:
  • through land users' innovation

3. Classification of the SLM Technology

3.1 Main purpose(s) of the Technology

  • conserve ecosystem

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

Land use mixed within the same land unit:

نعم

Specify mixed land use (crops/ grazing/ trees):
  • Silvo-pastoralism

الأراضي الزراعية

الأراضي الزراعية

  • Tree and shrub cropping
Tree and shrub cropping - Specify crops:
  • cashew
أراضي الرعي

أراضي الرعي

Comments:

Major land use problems (compiler’s opinion): Overgrazing, low soil fertility, sandy soils, monocultures, soil left bare after ploughing, wind and dust storms.
Major land use problems (land users’ perception): Low soil fertility, water scarcity, droughts.

Number of growing seasons per year: 1
Longest growing period in days: 210, Longest growing period from month to month: June to December
Livestock density: 25-50 LU /km2

3.4 Water supply

Water supply for the land on which the Technology is applied:
  • mixed rainfed-irrigated

3.5 SLM group to which the Technology belongs

  • integrated crop-livestock management

3.6 SLM measures comprising the Technology

vegetative measures

vegetative measures

  • V1: Tree and shrub cover
Comments:

Type of vegetative measures: aligned: -along boundary

3.7 Main types of land degradation addressed by the Technology

soil erosion by wind

soil erosion by wind

  • Et: loss of topsoil
chemical soil deterioration

chemical soil deterioration

  • Cn: fertility decline and reduced organic matter content (not caused by erosion)
biological degradation

biological degradation

  • Bc: reduction of vegetation cover
  • Bl: loss of soil life
Comments:

Main causes of degradation: soil management (Plowing of soil, then left bare), crop management (annual, perennial, tree/shrub) (Mainly annuals (rice) planted in monocultures.), overgrazing (Uncontrolled grazing.), labour availability (Little labour availability, mainly due to work in garment industry)

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:
  • reduce land degradation
  • restore/ rehabilitate severely degraded land

4. Technical specifications, implementation activities, inputs, and costs

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

On a dike cashews (Anacardium occidentale) were planted a few years back. After they grew up, the fence was done with barbed wire and bamboo poles.
Kampong Chhnang
Date: 2014

Technical knowledge required for field staff / advisors: low
Technical knowledge required for land users: low
Main technical functions: increase of biomass (quantity), spatial arrangement and diversification of land use
Secondary technical functions: increase in organic matter, increase in nutrient availability (supply, recycling,…), improvement of water quality, buffering / filtering water, reduction in wind speed

Aligned: -along boundary
Vegetative material: T : trees / shrubs, F : fruit trees / shrubs
Vertical interval within rows / strips / blocks (m): 0.5-3m
Fruit trees / shrubs species: Cashew, seeded.

Author:

Stefan Graf, Switzerland

4.2 General information regarding the calculation of inputs and costs

Indicate average wage cost of hired labour per day:

5.00

4.3 Establishment activities

Activity Timing (season)
1. Building small bound to sow the cashews. Dry season, before sowing
2. Sowing cashews on the bounds Beginning of rainy season
3. Gathering bamboo in the forest, building the fence

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
Labour labour 1,0 17,5 17,5 100,0
Equipment tools 1,0 12,0 12,0 100,0
Equipment barbed wire 1,0 21,0 21,0 100,0
Plant material seeds 1,0 1,0 1,0 100,0
Total costs for establishment of the Technology 51,5
Total costs for establishment of the Technology in USD 51,5
Comments:

Duration of establishment phase: 12 month(s)

4.5 Maintenance/ recurrent activities

Activity Timing/ frequency
1. Gathering bamboo in the forest, building the fence Every 2-3 years

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 labour 1,0 3,0 3,0 100,0
Total costs for maintenance of the Technology 3,0
Total costs for maintenance of the Technology in USD 3,0
Comments:

Machinery/ tools: Hoe, hatchet.
The costs were calculated for 100 m of living fence, with 2 stripes of barbed wires. The barbed wire is not necessary if enough labour and bamboo is available but makes it easier to keep the cattle fenced and requires less maintenance than bamboo poles.

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The costs are most determined by the availability of bamboo. If it is not grown in the garden, it has to be gathered in the forest that is related to time consuming transportation. Or barbed wire has to be purchased.
Note: The time used to gather the leaves for the compost or to cut the branches to make charcoal/ash as soil amendment was not included in the recurrent activities as these activities are neither related to the main purpose of living fences nor done by all the farmers applying this technology.

5. Natural and human environment

5.1 Climate

Annual rainfall
  • < 250 mm
  • 251-500 mm
  • 501-750 mm
  • 751-1,000 mm
  • 1,001-1,500 mm
  • 1,501-2,000 mm
  • 2,001-3,000 mm
  • 3,001-4,000 mm
  • > 4,000 mm
Specifications/ comments on rainfall:

1486.45 mm 2013 in Kampong Chhnang

Agro-climatic zone
  • sub-humid

Thermal climate class: tropics. 27-35°C

5.2 Topography

Slopes on average:
  • flat (0-2%)
  • gentle (3-5%)
  • moderate (6-10%)
  • rolling (11-15%)
  • hilly (16-30%)
  • steep (31-60%)
  • very steep (>60%)
Landforms:
  • plateau/plains
  • ridges
  • mountain slopes
  • hill slopes
  • footslopes
  • valley floors
Altitudinal zone:
  • 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 Soils

Soil depth on average:
  • very shallow (0-20 cm)
  • shallow (21-50 cm)
  • moderately deep (51-80 cm)
  • deep (81-120 cm)
  • very deep (> 120 cm)
Soil texture (topsoil):
  • coarse/ light (sandy)
  • medium (loamy, silty)
Topsoil organic matter:
  • medium (1-3%)
  • low (<1%)

5.4 Water availability and quality

Ground water table:

on surface

Availability of surface water:

good

Water quality (untreated):

poor drinking water (treatment required)

Comments and further specifications on water quality and quantity:

During wet seasons

5.5 Biodiversity

Species diversity:
  • medium
Habitat diversity:
  • medium

5.6 Characteristics of land users applying the Technology

Market orientation of production system:
  • mixed (subsistence/ commercial)
Off-farm income:
  • 10-50% of all income
Relative level of wealth:
  • average
Individuals or groups:
  • individual/ household
Level of mechanization:
  • manual work
  • animal traction
Gender:
  • women
  • men
Indicate other relevant characteristics of the land users:

Land users applying the Technology are mainly common / average land users
Population density: 10-50 persons/km2
Annual population growth: 0.5% - 1%
Off-farm income specification: handicraft, remittances and factory work

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

  • < 0.5 ha
  • 0.5-1 ha
  • 1-2 ha
  • 2-5 ha
  • 5-15 ha
  • 15-50 ha
  • 50-100 ha
  • 100-500 ha
  • 500-1,000 ha
  • 1,000-10,000 ha
  • > 10,000 ha
Is this considered small-, medium- or large-scale (referring to local context)?
  • medium-scale

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

Land ownership:
  • communal/ village
  • individual, not titled
Land use rights:
  • communal (organized)
  • individual
Water use rights:
  • open access (unorganized)
Comments:

Land users have a title that is not recognized by the state.

5.9 Access to services and infrastructure

health:
  • poor
  • moderate
  • good
education:
  • poor
  • moderate
  • good
technical assistance:
  • poor
  • moderate
  • good
employment (e.g. off-farm):
  • poor
  • moderate
  • good
markets:
  • poor
  • moderate
  • good
energy:
  • poor
  • moderate
  • good
roads and transport:
  • poor
  • moderate
  • good
drinking water and sanitation:
  • poor
  • moderate
  • good
financial services:
  • poor
  • moderate
  • good

6. Impacts and concluding statements

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

crop production

decreased
increased
Comments/ specify:

Due to shading and root competition.

wood production

decreased
increased
Comments/ specify:

Used as fuel and charcoal.

energy generation

decreased
increased
Comments/ specify:

Firewood production.

Water availability and quality

demand for irrigation water

increased
decreased
Comments/ specify:

Quality, trough bioremediation of groundwater. Difficult to quantify.

Income and costs

diversity of income sources

decreased
increased
Comments/ specify:

If spaced, production of cashew nuts and apples.

Socio-cultural impacts

food security/ self-sufficiency

reduced
improved
Comments/ specify:

Improved self-sufficiency on firewood.

contribution to human well-being

decreased
increased
Comments/ specify:

Every additional income source/diversification increases the human well-being.

Ecological impacts

Water cycle/ runoff

evaporation

increased
decreased
Comments/ specify:

But increased evapotranspiration.

Soil

nutrient cycling/ recharge

decreased
increased
Comments/ specify:

Nutrients are picked up from the groundwater, and put back into the cycle.

soil organic matter/ below ground C

decreased
increased
Comments/ specify:

Leaves used for compost.

Biodiversity: vegetation, animals

biomass/ above ground C

decreased
increased

beneficial species

decreased
increased
Comments/ specify:

Wormcasts could be seen under the trees. Difficult to quantify.

habitat diversity

decreased
increased
Comments/ specify:

Tree layer.

Climate and disaster risk reduction

wind velocity

increased
decreased

6.2 Off-site impacts the Technology has shown

groundwater/ river pollution

increased
reduced
Comments/ specify:

Bioremediation difficult to quantify.

wind transported sediments

increased
reduced
Comments/ specify:

Slowing down of wind speed.

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 well

Climate-related extremes (disasters)

Meteorological disasters
How does the Technology cope with it?
local rainstorm well
local windstorm well
Climatological disasters
How does the Technology cope with it?
drought well
Hydrological disasters
How does the Technology cope with it?
general (river) flood well

Other climate-related consequences

Other climate-related consequences
How does the Technology cope with it?
reduced growing period well

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?
Short-term returns:

neutral/ balanced

Long-term returns:

slightly positive

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?
Short-term returns:

slightly positive

Long-term returns:

slightly positive

6.5 Adoption of the Technology

Comments:

100% of land user families have adopted the Technology without any external material support
15 land user families have adopted the Technology without any external material support. These 15 families all live in this specific village. However, the technology is applied elsewhere as well.
A few years ago, one farmer could sell the cashew apples. Now there is an overproduction on the market.

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the land user’s view
Cattle are fenced in or off. The cattle do not enter the home gardens of the neighbours and cannot escape on the rice fields.
Branches can be used as firewood or to make charcoal, and the leaves can be used as compost
Production of fruits and nuts.
Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Reduced wind speed.
Bioremediation of groundwater.
Increased soil cover.

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?
Shading of crops nearby. Cut back the cashews since they are pollarding trees. However, this will drastically reduce the fruit production.
Root competition with other trees. Plant next to shallow rooted crops.
No more market for cashew apples as there is an overproduction. Process as wine or dry. Can also be fed to cattle.

7. References and links

7.1 Methods/ sources of information

  • field visits, field surveys
  • interviews with land users
When were the data compiled (in the field)?

06/08/2014

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