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)

Book project: where the land is greener - Case Studies and Analysis of Soil and Water Conservation Initiatives Worldwide (where the land is greener)

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

District Soil Conservation Office (DSCO) - Nepal

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

ICIMOD International Centre for Integrated Mountain Development (ICIMOD) - Nepal

1.3 Conditions regarding the use of data documented through WOCAT

When were the data compiled (in the field)?

01/11/2003

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

Ja

2.1 Short description of the Technology

Definition of the Technology:

Level bench terraces with risers protected by fodder grasses, used for the irrigated production of rice, potatoes and wheat

2.2 Detailed description of the Technology

Description:

The level bench terrace is a traditional technology that makes irrigated crop production possible on steep, erosion prone slopes. The majority of such terraces in Nepal were constructed by hand many generations ago, but some new land - mostly already under rainfed cultivation on forward sloping terraces - is still being converted into irrigated terraces. The initial costs for the construction of the terraces are extremely high – and annual maintenance costs are considerable also. The climate is humid subtropical, slopes are steep (30%-60%) and soils generally have a sandy loam texture. Terraces are cropped by farmers who mostly have less than 0.5 ha of land each.
Two to three annual crops are grown per year starting with paddy rice during the monsoon, followed by potatoes and/or wheat.
While terrace beds are usually 2–6 m in width, to save labour they are made as wide as they can be without increasing the danger of slips/land slides. Surveying was traditionally done by eye, but now a water-tube level may be used. Risers are 0.8-1.5 m high with a small lip (20-25 cm). The slope of the riser varies from 80 to 160%, depending on the initial gradient of the hill. Stones are incorporated in the risers if available, and grass species such as bermuda grass (Cynodon dactylon) and napier (Pennisetum purpureum) may be planted for stabilisation and as cattle fodder. The risers are compacted (with hoes) to improve ponding conditions for the paddy rice. Twice per year the risers are scraped with a special tool: (1) at the time of land preparation for paddy rice the lower part of riser is sliced, but the upper part is left protected with grasses against the monsoon rains; (2) at the time of wheat planting the whole riser (including the lip) is scraped and spread as green manure on the terrace.
Terraces are flooded with water for paddy rice cultivation: a smaller amount of water is diverted into the fields for other crops. Excess water is drained to the lower terrace by openings in the lip, which are filled with rice straw in order to filter out sediments. The depth of water for rice - when flooded completely - is normally between 10 and 15 cm. Fertility is maintained by addition of farmyard manure, spreading the scraped soil from the riser, and also through sediment carried in the irrigation water. Nowadays, mineral fertilizers are also applied.

2.3 Photos of the Technology

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

3.1 Main purpose(s) of the Technology

• improve production

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

Comments:

Major land use problems (compiler’s opinion): - steep slopes, not suitable for agriculture in their original state (better for forestry, agroforestry, horticulture, and fruit
trees)
- small and scattered plots of land
- land users find chemical fertilizers and water expensive
- there is water scarcity from September to May and too much rain in the monsoon period (June to August) with the danger of erosion and collapse of the terraces

3.3 Further information about land use

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

• rainfed

Number of growing seasons per year:

• 2

Specify:

Longest growing period in days: 150 Longest growing period from month to month: Jun - Oct Second longest growing period in days: 120 Second longest growing period from month to month: Nov - Feb

3.4 SLM group to which the Technology belongs

• cross-slope measure

3.5 Spread of the Technology

Specify the spread of the Technology:

• evenly spread over an area

If the Technology is evenly spread over an area, indicate approximate area covered:

• 0.1-1 km2

Comments:

Total area covered by the SLM Technology is 1 sq km2.

3.6 SLM measures comprising the Technology

Comments:

Main measures: agronomic measures, vegetative measures, structural measures

Type of agronomic measures: manure / compost / residues, mineral (inorganic) fertilizers

3.7 Main types of land degradation addressed by the Technology

Comments:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion, Wg: gully erosion / gullying, Wm: mass movements / landslides

3.8 Prevention, reduction, or restoration of land degradation

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

• prevent land degradation

4.1 Technical drawing of the Technology

4.2 Technical specifications/ explanations of technical drawing

Layout of irrigated terraces. Openings in the lips drain excess water, grass cover stabilises lips and risers (right). After harvesting of rice, the grass is scraped off the lower part of the risers (left) and spread on the terrace beds

Technical knowledge required for field staff / advisors: high

Technical knowledge required for land users: high

Main technical functions: reduction of slope angle, reduction of slope length, increase / maintain water stored in soil, control of dispersed and concentrated runoff, increase in soil fertility

Secondary technical functions: improvement of ground cover, water harvesting / increase water supply, water spreading

Manure / compost / residues
Material/ species: green/farmyard manure

Vegetative measure: fodder grass at risers

Terrace
Material: earth

4.3 General information regarding the calculation of inputs and costs

Specify how costs and inputs were calculated:

• per Technology area

Specify currency used for cost calculations:

• US Dollars

4.4 Establishment activities

	Activity	Type of measure	Timing
1.	Planting grasses including bermuda grass (Cynodon dactylon).	Vegetative	during monsoon
2.	Construct bunds (risers) with soil from upper and lower sides	Structural	before monsoon
3.	Level terrace beds (soil moved from upper to lower part of terraces).	Structural	before monsoon
4.	Make lips on edges of terraces	Structural	before monsoon
5.	Compact risers	Structural	before monsoon
6.	Construct irrigation canal	Structural	before monsoon
7.	Make openings in lips for drainage of excess water	Structural	before monsoon
8.	Test-irrigate terrace for accurate levelling	Structural	during monsoon
9.	Plant grasses including Bermuda grass (Cynodon dactylon)	Structural	during monsoon
10.	After 2–3 years: some narrow terraces may be merged to form single, wider terraces	Structural	during monsoon

4.6 Maintenance/ recurrent activities

	Activity	Type of measure	Timing/ frequency
1.	Flood the paddy fields ..	Agronomic	(June/July) / Repeated 3–4 times during
2.	Slice/scrape grass and soil on lower part of risers and spread on terraces	Agronomic	(when flooded, June/July) /
3.	Plant rice and apply mineral fertilizer	Agronomic	(June/July). /
4.	Harvest rice	Agronomic	(October) /
5.	Apply manure (cattle manure), after rice harvest	Agronomic	(October). /
6.	Slice/scrape grass and soil from whole of risers and spread on terraces; repairsmall collapses/slumps in risers	Agronomic	(October/November) /
7.	Pprepare land	Agronomic	(November) /
8.	Apply mineral fertilizer	Agronomic	(November/December). /
9.	Irrigate	Agronomic	Nov. / repeated several times during cultivation
10.	Harvest of potato/wheat	Agronomic	(January-March). /
11.	Planting of rice	Vegetative	June,July /
12.	planting of potatoes, wheat	Vegetative	November /
13.	Repair of small collapses/slumps in risers.	Structural	(Oct./Nov.)/

4.7 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	ha	1.0	350.0	350.0	100.0
Equipment	Tools	ha	1.0	5.0	5.0	100.0
Fertilizers and biocides	Fertilizer	ha	1.0	185.0	185.0	100.0
Fertilizers and biocides	Compost/manure	ha	1.0	300.0	300.0	100.0
Total costs for maintenance of the Technology					840.0

Comments:

Machinery/ tools: hoe, spade, baskets, (doko), special tool for scraping

Current establishment costs are very difficult to determine since the majority of the traditional terraces were
established a long time ago. Costs depend closely on the present state of the land (forward sloping terraces or uncultivated) and the need for irrigation canals. Farmers say that construction now could cost up to US$ 10,000 per ha if carried out by hand at full labour cost. The cost given for maintening the terraces (approx. US$ 840 per ha) includes all associated annual crop production costs. In this case study, 100% of the construction costs were borne by land users.

5.1 Climate

5.2 Topography

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.

Soil fertility is medium

Soil drainage / infiltration is good because of the geology and soil texture (loam)

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Off-farm income specification: hired labour (on other farmers’ fields) or as porters

Market orientation of production system: Subsistence (rice/wheat) and commercial (potatoes)

5.7 Average area of land owned or leased by land users applying the Technology

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

Land ownership:

• individual, not titled

Land use rights:

• leased
• individual

Comments:

Land use rights: leased (90% of farmers), individual (10%)

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Other socio-economic impacts

Socio-cultural impacts

Ecological impacts

Water cycle/ runoff

Soil

Climate and disaster risk reduction

Other ecological impacts

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	Type of climatic change/ extreme	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	not well
local windstorm	not well

Climatological disasters

	How does the Technology cope with it?
drought	not well

Hydrological disasters

	How does the Technology cope with it?
general (river) flood	not well

Other climate-related consequences

Other climate-related consequences

	How does the Technology cope with it?
reduced growing period	not well

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)?

6.5 Adoption of the Technology

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

• 90-100%

Comments:

100% of land user families have adopted the Technology without any external material support

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Income and production increased How can they be sustained / enhanced? Proper management of the terraces (including all maintenance activities)
Easier to cultivate flat terraces/less labour required (after establishment of terraces)
Work sharing: traditional terraces are part of a long tradition of work sharing within the community with no external labourneeded How can they be sustained / enhanced? Prevent loss of well established traditions and norms
Technology is easy to understand/apply. Increased opportunities for irrigation facilities: farmers without level terraces are not allowed (by the irrigation committee at village level) or do not claim irrigation water
The irrigation element of this technology fosters social bonds within the community How can they be sustained / enhanced? Prevent loss of well established norms and traditions.

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

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
Decreased grass production (grazing area reduced)	Promote planting of high value grass species on risers (such as bermuda grass).
The farmers believe that the terraces are too narrow (for efficient use of tractors); they would like to have wider terraces	Investigate possibilities of constructing wider paddy rice terraces on steep slopes, which, according to present experience, is not possible.
High labour costs for establishment.

7.2 References to available publications

Title, author, year, ISBN:

There is considerable literature on the construction and maintenance of irrigated terraces in general, but no references thatspecifically describe the traditional paddy rice terraces in Nepal