Technologies

Terrace [China]

Terrace

technologies_1367 - China

Completeness: 65%

1. General information

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

Key resource person(s)

SLM specialist:
Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)
Department of Resources and Environmental Science, Beijing Normal University (Department of Resources and Environmental Science, Beijing Normal University) - China

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:

Ja

2. Description of the SLM Technology

2.1 Short description of the Technology

Definition of the Technology:

A terrace is a kind of measure to change the slope, which has a raised bank of earth or stone with vertical or sloping sides and a approximately flat top.

2.2 Detailed description of the Technology

Description:

A terrace has a raised bank of earth or stone with vertical or sloping sides and a approximately flat top. It can reduce slope angle and length, retain runoff, increase infiltration and reduce the soil loss. Crops can grow well because water increases in soils. Meanwhile, ground cover is improved. Terrace can be constructed by manual labor or machine. Firstly, determining the width of the field according to the slope angle and soil texture. Secondly, putting the topsoil aside. Thirdly, leveling up the slope and constructing banks. At last, putting the topsoil to the top of the flat surface.

2.3 Photos of the Technology

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

Country:

China

Region/ State/ Province:

Shaanxi, Shanxi, Inner Mongolia, Henan, Gansu

Specify the spread of the Technology:
  • evenly spread over an area
If the Technology is evenly spread over an area, specify area covered (in km2):

26666.7

If precise area is not known, indicate approximate area covered:
  • > 10,000 km2
Comments:

Total area covered by the SLM Technology is 26666.7 km2.

Terrace is one of the most outstanding achievements in SWC in China. It can prevent soil and water loss so that slope land can be sustainable development. There are about 26.7 million ha of terrace in China, of which more than 13.3

2.6 Date of implementation

If precise year is not known, indicate approximate date:
  • more than 50 years ago (traditional)

2.7 Introduction of the Technology

Specify how the Technology was introduced:
  • as part of a traditional system (> 50 years)
Comments (type of project, etc.):

Summary from farmers' long term experience in SWC, later being innovated.

3. Classification of the SLM Technology

3.1 Main purpose(s) of the Technology

  • reduce, prevent, restore land degradation

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

Cropland

Cropland

  • Annual cropping
  • Tree and shrub cropping
Annual cropping - Specify crops:
  • cereals - maize
  • legumes and pulses - peas
Number of growing seasons per year:
  • 1
Specify:

Longest growing period in days: 160Longest growing period from month to month: May-Sep

Comments:

Major land use problems (compiler’s opinion): Soil and water lose seriously, soil degrades, soil fertility decreases and crop yield declines.

Major land use problems (land users’ perception): crop yield declines, weak ability of resisting drought

3.4 Water supply

Water supply for the land on which the Technology is applied:
  • rainfed
Comments:

Water supply also mixed rainfed - irrigated

3.5 SLM group to which the Technology belongs

  • cross-slope measure

3.6 SLM measures comprising the Technology

structural measures

structural measures

  • S1: Terraces

3.7 Main types of land degradation addressed by the Technology

soil erosion by water

soil erosion by water

  • Wt: loss of topsoil/ surface erosion
Comments:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion

3.8 Prevention, reduction, or restoration of land degradation

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

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

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

Drawings of a terrace building in the Loess Plateau

Location: the Loess Plateau. Shaanxi, Shanxi, Henan, Gansu, Inner Mongolia

Date: 2002

Technical knowledge required for field staff / advisors: high

Technical knowledge required for land users: low

Main technical functions: reduction of slope angle, reduction of slope length

Construction material (earth): Construct ridge of terrace

Construction material (stone): Construct ridge of terrace

Slope (which determines the spacing indicated above): 25%

If the original slope has changed as a result of the Technology, the slope today is: 10%

Lateral gradient along the structure: 80%

For water harvesting: the ratio between the area where the harvested water is applied and the total area from which water is collected is: 1:6

Author:

BAI Zhanguo, Beijing China

4.2 General information regarding the calculation of inputs and costs

Specify currency used for cost calculations:
  • USD
Indicate average wage cost of hired labour per day:

3.00

4.3 Establishment activities

Activity Timing (season)
1. survey After harvesting crop
2. constructing terrace: determine the excavation line which should make the excavation and the filling equal and the least workload After harvesting crop, before raining season
3. constructing terrace: pilling mellow soil up to the middle of a bench After harvesting crop, before raining season
4. constructing terrace: moving the immature soil of lower part to fill the upper part or moving the soil from inside to fill up outside After harvesting crop, before raining season
5. constructing terrace: building the ridge After harvesting crop, before raining season
6. constructing terrace: spreading the mellow soil on the surface After harvesting crop, before raining season

4.4 Costs and inputs needed for establishment

Comments:

Duration of establishment phase: 12 month(s)

4.5 Maintenance/ recurrent activities

Activity Timing/ frequency
1. periodically inspecting After a storm/About 1 year
2. repairing where terrace is collapsed Whenever finding it is destroyed/timely
3. level up the field after harvesting crops/timely

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

Comments:

Terrace section, building by bulldozer.

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The factors are topography, soil texture, means of construction. The section of terrace is the most important factor.

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
Specify average annual rainfall (if known), in mm:

449.00

Agro-climatic zone
  • semi-arid

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.
Comments and further specifications on topography:

Slopes on average also rolling

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):
  • medium (loamy, silty)
Topsoil organic matter:
  • low (<1%)
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: low

Soil drainage / infiltration: good

Soil water storage capacity: low

5.6 Characteristics of land users applying the Technology

Off-farm income:
  • 10-50% of all income
Relative level of wealth:
  • average
  • rich
Level of mechanization:
  • animal traction
  • mechanized/ motorized
Indicate other relevant characteristics of the land users:

Population density: 100-200 persons/km2

Annual population growth: < 0.5%


Relative level of wealth: all selected

Relative level of wealth: very rich, rich, average, poor, very poor

5% of the land users are very rich and own 10% of the land.
10% of the land users are rich and own 10% of the land.
70% of the land users are average wealthy and own 60% of the land.
10% of the land users are poor and own 10% of the land.
5% of the land users are poor and own 10% of the land.

Off-farm income specification: estimate

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

Land ownership:
  • state
  • communal/ village

6. Impacts and concluding statements

6.1 On-site impacts the Technology has shown

Ecological impacts

Water cycle/ runoff

surface runoff

increased
decreased
Quantity before SLM:

10

Quantity after SLM:

4

Soil

soil loss

increased
decreased
Quantity before SLM:

180

Quantity after SLM:

58

6.4 Cost-benefit analysis

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

very negative

Long-term returns:

very positive

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

negative

Long-term returns:

very positive

6.5 Adoption of the Technology

Comments:

80% of land user families have adopted the Technology with external material support

Comments on acceptance with external material support: estimates

20% of land user families have adopted the Technology without any external material support

Comments on spontaneous adoption: estimates

There is a little trend towards spontaneous adoption of the Technology

Comments on adoption trend: If they have enough money, they would like to do, because they have known the benefits from terraces.

7. References and links

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

(inner resources) Suide Water and Soil Conservation examination station of Yellow River Water Resources Committee.. 1981.

Available from where? Costs?

orpus of Test Research of Water and Soil Conservation (the second volume), p130~185.

Title, author, year, ISBN:

(inner resources) Water and Soil Conservation Department of Yellow River Water Resources Committee of Ministry of Water Resources and Electric Power.. 1987.

Available from where? Costs?

Corpus of economic benefits of water and soil measures, p77~102 ,510~514

Title, author, year, ISBN:

Dongyinglin,Changpiguang ,Wangzhihua. Discussion on the several questions on increasing production of the terrace with two banks.. 1990.

Available from where? Costs?

Soil and Water Conservation Science and Technology in Shanxi, No.1, p36~37

Title, author, year, ISBN:

Jiangdingsheng. Discussion on section design of the terrace on the Loess Plateau.. 1987.

Available from where? Costs?

ACTA CONSERVATIONIS SOLI ET AQUAE SINICA, Vol.1, No.2,p28~35.

Title, author, year, ISBN:

Liangqichun, Changfushuang , Liming. A study on drawing up budgetary estimate quota of terraced field.. 2001.

Available from where? Costs?

Bulletin of Soil and Water Conservation, Vol.21,No.5, p41~44.

Title, author, year, ISBN:

Liumingquan, Zhangaiqin, Liyouhua. Pattern engineering of reconstruction the slope cropland.. 1992.

Available from where? Costs?

Soil and Water Conservation Science and Technology in Shanxi, No.3, p18~21.

Title, author, year, ISBN:

Lixuelian,Qiaojiping. Synthetic technology of fertilizing and improving production on the new terrace.. 1998.

Available from where? Costs?

Soil and Water Conservation Science and Technology in Shanxi, No.3, p13~14.

Title, author, year, ISBN:

Ministry of Water Resources of China. Terraces in China.. 1989.

Available from where? Costs?

The press of Jilin science & technology.

Title, author, year, ISBN:

Wangxilong,Caiqiangguo,Wangzhongke. The consolidating function and economic benefit analysis of the terrace hedgerows in the hilly loess region of northwest Hebei Province.. 2000.

Available from where? Costs?

Journal of Natural Resources,Vol.15, No.1, p74~79.

Title, author, year, ISBN:

Xuyuanxu.The surveying report of the terrace benefits in yanbian autonomous prefecture. 1995.

Available from where? Costs?

Water and Soil Conservation,No.4, p50~52.

Title, author, year, ISBN:

Zhujianqiang,Lijing. Experimental study on soil compact characteristics and its shearing strength in changing slope field into terrace on south shaanxi province.. 2000.

Available from where? Costs?

ransaction of the CSAE,Vol.16, No.2, p36~40.

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