Contour trenches and contour strips
Type: Technologies
Creation: 2025-05-29 16:10 Updated: 2025-10-08 16:06
Compilers: Joren Verbist
Reviewers: William Critchley, Rima Mekdaschi Studer
Country/ region/ locations where the Technology has been applied and which are covered by this assessment
- Country: Uzbekistan
- Region/ State/ Province: Qashqadaryo Province in southern Uzbekistan
- Further specification of location (e.g. municipality, town, etc.), if relevant: 8°43'14.26"N, 66°41'51.87"E
- Map: View Map
Description of the SLM Technology
Short description of the Technology
Contour trenches for the cultivation of almond trees, and contour strips for cereals are types of rainwater harvesting structures. They are designed to capture runoff, reduce erosion, and enhance soil moisture—thereby improving land productivity and supporting climate-resilient agriculture in lowland dry areas.
Detailed description of the Technology
Qashqadaryo Province in southern Uzbekistan experiences a hot, dry summer and a mild winter. Combined with unsustainable land management practices, climatic stresses have exacerbated land degradation and made local livelihoods increasingly vulnerable.
As part of the Food Systems, Land Use and Restoration (FOLUR) project, the International Center for Agricultural Research in the Dry Areas (ICARDA) designed and tested rainwater harvesting (RWH) structures to combat land degradation and enhance rural livelihoods. These RWH structures support vegetation growth, reduce surface runoff, prevent erosion, and restore soil health—thereby reversing degradation and improving agricultural productivity.
Based on slope gradients and hydrological characteristics, two RWH techniques were selected: modified contour trenches for the slightly sloping upper areas, and modified contour strips for the flatter zones.
In the upper portion of the site, which spans 1.54 hectares, modified contour trenches were implemented for perennial tree crops. Design calculations suggested a spacing of 8 metres between trenches, and 7 metres between almond trees along each trench.
Implementation began with the marking of contour lines using a laser level: two labourers worked for two days. Then a tractor fitted with a three-mouldboard plough dug the trenches. While the tractor generally performed well, work had to be completed manually at sharp bends and gully crossings. Eight labourers then spent two days shaping and stabilizing the trenches. In total, approximately 1,300 metres of trench lines were created.
Costs were relatively modest. The tractor, hired from a farmer, cost $150 per day. Manual labour amounted to 24 person-days at $10 per day. 100 almond trees were planted, and 85 tamarix trees were added as a protective windbreak.
In the lower, flatter part of the site—about 1.68 hectares—standard contour strips were unsuitable due to the very low slope, which would not generate enough runoff. Instead, a modified version was implemented. Low ridges along contour at a vertical interval of 30 cm, allowed rainwater to pool and infiltrate. The same tractor was used with a single mouldboard plough to form nine contour ridges, shaped by two passes.
Afterwards, ten local women labourers finalized the ridges manually. The total length of the contour strips reached 500 metres, and the ratio of catchment to cultivated area varied from 5:1 in the upper sections to 1:1 in the lower zones, based on expected runoff.
The cost of this phase included one day of tractor use and 15 person-days of labour, totalling approximately $300. This site is intended for rainfed cultivation, and will follow a crop rotation system including barley, legumes and fallow periods. Over time, farmers are encouraged to adopt no-till practices to improve soil health.
Following implementation, light rainfall provided a test of the structures. Both the contour trenches and strips performed as intended, with no damage observed.
The interventions demonstrate how a tailored combination of RWH structures and cropping systems can rehabilitate degraded land. Local involvement helped to build community ownership. The result is a more productive and climate-resilient landscape that offers long-term benefits for soil conservation and rural livelihoods.
Acknowledgement: This SLM was introduced by ICARDA in the framework of Food Systems, Land Use and Restoration Impact Program (FOLUR) in Uzbekistan (GCP/UZB/010/GFF), implemented by FAO with funding from the Global Environment Facility (GEF)
Photos of the Technology
- 🗓 2026-04-03
- 📷 ICARDA
- 🗓 2026-04-03
- 📷 ICARDA
- 🗓 2026-04-03
- 📷 ICARDA