UNCCD

Bench Terracing [Bhutan]

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Reporting Entity: Bhutan

Clarify if the technology described in the template, or a part of it, is covered by property rights: Não

Completeness: 80%

General Information

General Information

Title of best practice:

Bench Terracing

Country:

Bhutan

Reporting Entity:

Bhutan

Property Rights

Clarify if the technology described in the template, or a part of it, is covered by property rights:

Não

Specifications

Section 1. Context of the best practice: frame conditions (natural and human environment)

Short description of the best practice

Bench terracing is a technology employed in soil conservation activities. It consist of a series of level or nearly level strips running across a slope following the contour lines at certain vertical intervals. The gentler the slope, greater is the width of the terrace, and the reverse is true for steeper slopes. Bench terracing is not recommended at slopes > 30°. At this angle, the riser heights become too high. The levels of strips (i.e. the terraces) are supported by steep banks or risers made of earth or rocks. Grass slips are planted on the riser slopes to ensure faster slope stabilization. Establishment of terraces reduce both the amount and the velocity of water moving over the soil surface. In the process, this reduces soil erosion and retains soil nutrients on-site. |

Location

3) Chhukha District: Phuntsholing, Bongo and Logchina Gewogs.|

Brief description of the natural environment within the specified location.

1) Radhi: altitude ranges from 1040 m above sea level (asl) to 2900 m asl, Lumang: 1100 m to 3000 m asl, Thrimshing: 1000 m to 3200 m asl.
2) Nangkhor: 280 m to 4600 m asl, Bardo: 200 m to 3300 m asl, Goshing: 200 m to 2400 m asl.
3) Phuntsholing: 180 m to 2400 m asl, Bongo: 200 m to 3900 m asl, Logchina: 500 m to 2500 m asl.
Because the landform in Bhutan is characterised by steep to very steep slopes incised by deep valleys, the slopes vary considerably in the reported areas.
Radhi: Deep yellowish-reddish brown (rbr) sandy clay loam (SCL), Lumang: Mod deep-deep dark grayish brown (dgbr) to brown sandy loam (SL) to silty clay loam (ZiCL), Thrimshing: Mod deep-deep dgbr to brown ZiCL.
Nangkhor: Shallow-mod deep dgbr SL, Bardo: Shallow-deep v.dgbr to yellowish brown (ybr) SL to ZiL, Goshing: Mod deep-deep gdbr to ybr ZiL to ZiCL.
P/ling: Mod shallow-deep gbr ZiL to ZiCL, Bongo: Shallow-deep v.dgbr to ybr ZiLto ZiCL, Logchina: Shallow-mod deep dgbr to ybr SL to SCL.
1) Radhi: Sub-tropical - warm temperate climatic conditions (CC), Lumang: Sub-tropical – cool temperate, Thrimshing: Humid tropical – cold temperate.
2) Nangkhor: Sub-tropical to - cool temperate, Bardo: Wet tropical – cold temperate, Goshing: Wet tropical – warm temperate.
3) Phuntsholing: Sub-tropical with very high rainfall averaging about 4,500 mm annually, Bongo: Wet tropical – sub alpine, Logchina: Wet tropical – warm temperate climatic conditions.

Prevailing socio-economic conditions of those living in the location and/or nearby

The main livelihood source of the rural communities of these areas is crop agriculture with supplementary livelihood from livestock production. Besides, farmers also earn cash income from off-farm activities such as construction industry. Unlike in other reported areas, farmers in Logchina practice apiculture out of which they generate good income.|
Land in the reported areas are privately owned by the farmers and it ranges from parcel size of minimum less than 1 acre (small fraction of the population) to maximum of 10 acres. The average land holding is about 2.5 acres.
Amongst the reported gewogs, Bardo and Goshing Gewogs of Zhemgang Dzongkhag and Bongo and Logchina Gewogs of Chhukha Dzongkhag, are comparatively remote with poor accessibility to road networks. Generally, other areas do have good access to road and other public facilities. Furthermore, most of the farmers are self sufficient too.|

On the basis of which criteria and/or indicator(s) (not related to The Strategy) the proposed practice and corresponding technology has been considered as 'best'?

The proposed practice has been considered 'best' because of its efficiency and effectiveness in controlling soil erosion where the agricultural practice is on steep lands; which is the case in Bhutan. On the other hand, the investment is considerably high in the beginning, but this is compensated by by an increased return from the agriculture productions in the later stages. |

Section 2. Problems addressed (direct and indirect causes) and objectives of the best practice

Main problems addressed by the best practice

1) Soil erosion on moderately steep slope up to 30°,
2) Loss of soil nutrients due to soil erosion,
3) Ease workability by construction of either flat, or partially flat terraces,
4) Moisture stress problems which is achieved through retention of runoff water and increment of on-site water infiltration.|

Outline specific land degradation problems addressed by the best practice

Since the agricultural farming is mainly practised on the steep slopes across Bhutan, the heavy rainfall and loose soil structures make the Country's agricultural landscape highly vulnerable to soil erosion and other forms of land degradation. This is more severe on drylands as irrigated paddy land is always terraced. Hence, bench terracing on the dryland is, without denial, an ideal sustainable land management technology in addressing the issue of land degradation and in the process promote sustainable farming needs in Bhutan's mountainous terrain. |

Specify the objectives of the best practice

Control soil erosion, maintain soil fertility, promote intensive cultivation and increase the ease of workability- which all combines towards contributing to increased and sustainable crop production.|

Section 3. Activities

Brief description of main activities, by objective

Capacity Building: This is required to train farmers on how to establish, design and construct bench-terraces. During the training, extension agents and farmers are educated about the functions provided by this physical SLM structures and the forage values of the grass species planted on riser slopes.|
Education and Awareness Raising: Demonstration plots have also been established to raise awareness and at the same time educate stakeholders such as extension agents and farmers; both local and regional.
Promotion of SLM Adoption: Farmers don't accept the introduction of new technology in their fields willingly. In order to get fairly easy access and placement of technology, provision of incentives such as supply of tools and free planting materials have become necessary. However, this has to be prioritized for those trained farmers who belong to poor households. |

Short description and technical specifications of the technology

The technology- bench terracing is not recommended beyond 30° slope. Slopes of the proposed sites are determined prior to the commencement of terracing. The vertical intervals of the terraces are marked based on the slope gradient. Once marking of vertical interval is done, contour lines are run across the slope using A-frame that serves as a very important terracing tool. Once the contour lines are laid across the slope, cut and fill areas of the terraces are clearly demarcated. From the cut area, topsoil is completely removed and piled it in one of the corners. Then, terrace levelling is done using the subsoil. This is followed by re-spreading the topsoil that was saved in the earlier phase over the surface of the terraces. Performing this is very crucial to put back the organic rich topsoil so that the farmers can cultivate right after the terracing works are over without much loss of soil fertility. After this, mulching is done to prevent soil erosion by reducing the impacts of rain water. Additionally, plantations of fodder grass slips are done along the terrace riser slopes to stabilise it. This is crucial since there are chances that the terrace riser may collapse, if left neglected.|

Section 4. Institutions/actors involved (collaboration, participation, role of stakeholders)

Name and address of the institution developing the technology

National Soil Services Centre, Department of Agriculture (Ministry of Agriculture and Forests)|Post Box No. 907, Semtokha, Thimphu, Bhutan.

Was the technology developed in partnership?

Não

Specify the framework within which the technology was promoted

  • National initiative – government-led
  • Programme/project-based initiative

Was the participation of local stakeholders, including CSOs, fostered in the development of the technology?

Sim

List local stakeholders involved:

Local stakeholders include the local communities, the Gewog Renewable Natural Resource (RNR) extension agents and RNR staff from Dzongkhags (including Agriculture, Livestock and Forestry sectors) and local government.|

For the stakeholders listed above, specify their role in the design, introduction, use and maintenance of the technology, if any.

1) Local communities: They are the target beneficiaries. Their main roles include participation in the training, adopt and promulgate the best practices and provide feedback for further improvement of the technology,
2) The Gewog RNR extension agents: They perform vital functions such as providing hands on training, providing technical backstopping and also monitoring the implementation of the best practices by the farmers,
3) Dzongkhag RNR sectors: They prepare Sustainable Land Management (SLM) plans, mobilize resources and provide technical back stopping to the field staff. They act as a bridge between the Central Government Institutions and the field extension agents,
4) Members of the local government: They facilitate introduction of technology in their locality.|

Was the population living in the location and/or nearby involved in the development of the technology?

Sim

By means of what?
  • Consultation
  • Participatory approaches

Analysis

Section 5. Contribution to impact

Describe on-site impacts (the major two impacts by category)

The fodder grass slips that are planted on the riser slopes of the terraces provides additional forage resources. This encourage stall feeding of cattle. Hence this practice curtails free-grazing in the open spaces and in the woodlands. Therefore, this reduces land degradation due to overgrazing.|
Terracing activities are labour intensive. However, once terracing is achieved and is in place, it is one of the best sustainable land management technologies to combat physical land degradation, especially with the landform characterized by steep slopes incised by deep valleys.|
When there is reduced soil erosion on the upper catchments (up-slope), there is less sediment load going into the streams and rivers. This reduces siltation of hydro-power dams and water reservoirs and hence, there is less impact on the water ecology.|
The fodder grass planted on the terrace riser slopes provides supplement forage to the livestock animals, particularly cattle, hence increasing the livestock productivity. As a result, farmers can derive supplementary income from this.|
Bench terracing improves livelihoods of the stakeholders (farmers) since they can go for intensive agriculture production.
Terracing reduces soil erosion and in the process maintains soil fertility, thereby, enabling intensive agriculture production. Furthermore, creation of uniform land surface increases the workability by great degrees.|

Describe the major two off-site (i.e. not occurring in the location but in the surrounding areas) impacts

Having terraces placed on steep lands reduces the sediment load going into the water bodies (streams and river systems). This reduces siltation of hydro-power dams and water reservoirs. Therefore, this minimises the siltation effect on water bio-diversity.|

Impact on biodiversity and climate change

Explain the reasons:

The technology has positive impacts on biodiversity conservation through its contribution in maintaining land in terms of its productivity and physical size on which the biodiversity flourish. On the other hand, having better soil conservation measures in place will reduce the vulnerabilities of agriculture landscapes to climate related disasters such as land degradation, flash floods, and drought. Since, Bhutan is characterized by rugged terrain, fragile geological set-up and more frequent erratic climatic conditions; it is more vulnerable to destructive phenomena such as flash floods, landslides and droughts. The proposed practice will enable the farming communities to cope better with the climate change impacts (adaption) and enhance food security through prevention and mitigation of land degradation, intensive crop cultivation and conservation of soil moisture during the prevalence of dry spells which might be caused by the erratic climatic events.

Has a cost-benefit analysis been carried out?

Has a cost-benefit analysis been carried out?

Não

Section 6. Adoption and replicability

Was the technology disseminated/introduced to other locations?

Was the technology disseminated/introduced to other locations?

Sim

Where?

The fragile agricultural slopes across Bhutan received little attention in terms of sustainable land management (SLM) inputs vis-à-vis introduction of technologies. Starting late 1970’s and early 1980’s, stone bunding and wetland terracing were very few land management technologies promoted by the government by providing financial incentives. This was as far as it went till late 1990’s and early part of year 2000. Though it was one of the biggest revenue generating sector, it failed to get enough attention [strictly- in SLM domain], partly because the government was placing the social sectors such as education and health in the fore-front of development. However, gradual changes occurred since the year 2004 when the Ministry of Agriculture and Forests (MoAF; alias Ministry of Agriculture) placed physical land degradation issues on a visible platform of the nation.  Since, 2004, the MOAF has been making relentless efforts in addressing land degradation issues especially in the agricultural fields and in the vicinity of it. This was kick-started with the field assessment on severity of land degradation under Trashigang Dzongkhag, in 2004, which was carried out by the National Soil Services Centre. Then, vigorous bio-engineering training was conducted for RNR extension staff from the selected sites and nearby Dzongkhags. After achieving this, the first national level land management campaign (LMC) was conducted in Trashigang Dzongkhag in July 2005. The activities were implemented in 8 Gewogs (blocks). With participants from MoAF, Dzongkhags, Local Governments, RNR extension agents and local communities, SLM technologies were placed in the affected areas. The activities included establishments of hedgerows, bench terracing, plantations, gully protection techniques such as check-dams, etc. Over 25 ha of land were brought under SLM during the year. The RNR sectors under MoAF continued to work jointly in addressing land degradation issues. Additionally, other organizations, RNR Research Centres have taken very active roles in working towards addressing land degradation. To promote the horizontal spread of SLM activities in the degradation prone areas, the LMC activity was replicated each year, covering an average of 40 acres. By the end of 2011, over 270 acres of land were brought under SLM practices. The area excludes the ones from the reported best practices which covers over 11,390 acres.|

Were incentives to facilitate the take up of the technology provided?

Were incentives to facilitate the take up of the technology provided?

Sim

Specify which type of incentives:
  • Financial incentives (for example, preferential rates, State aid, subsidies, cash grants, loan guarantees, etc)
  • Fiscal incentives (for example, exemption from or reduction of taxes, duties, fees, etc)

Can you identify the three main conditions that led to the success of the presented best practice/technology?

Labour sharing mechanism developed within the community to address labour shortage problem and cost saving in implementing this resource intensive technology.
Bench terracing is done in a very participatory manner. This involves both local farmers and field extension agents in design and construction of terraces. On the other hand, this is partly due to the presence of highly motivated field extension agents and their positive interactions with the local farmers.|
Existence of strong cohesion between and amongst the farmers and their high level of interest towards addressing land degradation issues.

Replicability

In your opinion, the best practice/technology you have proposed can be replicated, although with some level of adaptation, elsewhere?

Sim

At which level?
  • Local
  • Sub-national
  • National
  • Subregional
  • Regional
  • International

Section 7. Lessons learned

Related to human resources

The implementation of this technology requires labour. Fortunately, this has been addressed by adopting labour sharing groups from within the community/communities. This calls for collective approach rather than a single household effort. However, with increasing rural-urban migration, the practice needs to be made more labour-efficient, for instance by employing terracing machinery (for instance, spider machine) on subsidized rates. |

Related to technical aspects

The technology is very simple and easily understood by the farmers. Therefore, basic training programmes are sufficient to build requisite knowledge and skills of the farmers. This, in turn, has helped in lowering the training  and extension costs. However, with a desire to bring more areas under terracing, stakeholders become tempted and overlook the maximum permissible slope i.e. 30°), least realising that terraces with high riser heights can collapse later on, thus making it unsustainable.|

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