 |
Soil and Water Management Techniques for Plant Resources Conservation in the Northern Burkina Faso
|
| Overview | Agriculture in the Sahelian zone like the northern part of Burkina Faso is essentially rainfed. Because of frequent droughts and land degradation, it is more and more difficult for crops to have enough water during their growing period. Farmers of this region have developed several soil and water management techniques like stony lines associated or not with the Zai system. This consists of digging holes during the dry season, putting a small quantity of manure into them and waiting for the raining season to sow seeds. Other techniques have been developed in this region over the past 20 years by many development projects, NGOs with the assistance of research institutions. |
| Scale | Field, farm, landscape, region |
| Location | The site is located at 2.7 ºW, 14.0 º N in the Yatenga province near the town of Ouahigouya |
| Elevation | 300 to 350 meters |
| Climate | Tropical savanna cooler uplands stippled. Annual rainfall range from 400 to 700 mm. Raining season goes from June to September. Annual mean Potential Evapotranspiration (PET) can reach 2000mm. Minimum temperature 13º-15º C. maximum temperature 40º-45º C. |
| Agricultural Region | Shifting cultivation |
| Population Density | 60 persons / square kilometer |
| Principle Crops | Sorghum (Sorghum bicolor) and Millet ( Pennisetum glaucum) |
| Domestic Animals | Cows, Oxen, Sheep, Goats, Chicken, Donkeys, Horses, Camels, Pigs, and Guinea fowl |
| Soils | Alfisols : Ustalfs , warm subhumid to semi-arid; dry >90 days |
| Natural Vegetation | Grass and other herbaceous plants. Broadleaf deciduous, shrubform, minimum height 3 feet, growth singly or in groups or patches |
| Ecoregion | Tropical/Subtropical steppe province. Dry steppe, desert shrub, semi-desert savanna |
| Basic Principles addressed | Use Renewable Resources, Conserve Resources, Minimize Toxics, Manage Ecological Relationships, Adjust to Local Environments, Diversify, Empower People, Manage Whole Systems, Maximize Long-Term Benefits, Value Health |
| Page Author and Date | Leopold Some, senior researcher in soil and water management and agroclimatology Institut de l`Environnement et de Recherches Agricoles (INERA), 2001 |
|
In past decades, development projects, NGOs and the national extension service have developed several techniques for conservation of land and rainwater on the field scale in order to mitigate the effects of drought. Among these techniques are stony lines, half-moon, mulch and boulis (a sort of well dug at the base of a thalweg or any water way, for watering animals or vegetables during the dry season). Stony lines are generally combined with a Zai system. They are stabilized with a plantation of Andropogon gayanus or with a tree plantation. The system is very efficient to restore fertility to barren soils called zipelle in Moore (the language of Mossi ethnic group living in this region). This agroecological system has an impact on plant resources in situ conservation. Surveys will be made in 2001 in this region to estimate the extent of the impact. Nine villages have been selected for conventional surveys and two of them with a participatory approach (Rural Appraisal Technique). In each village a random sample of 30 farmers (15 males and 15 females) will be chosen to answer a list of questions previously prepared. This research is an activity of a project financed by the International Plants Genetics Research Institute (IPGRI). Surveys aimed 1) to determine local people's understanding of the degradation of their environment (rainfall, vegetation, and land); and 2) to determine if the techniques will restore biodiversity. |
|
Peoples of this region determined to overcome land degradation and apply techniques that contribute mitigating the effects of drought. They realized that their environment has changed over the last fifty years in terms of reduced rainfall, diminishing vegetation, and disappearance of some species. Erosion has completely removed the topsoil in some areas. Crops like yam, cotton, and cassava formerly grown have completely disappeared nowadays. But on the fields where land and water management have been applied for about 20 years, formerly disappeared tree species grow again. Without soil and water saving techniques, crops yield range from 0 to 300 Kg/ha according to annual rainfall. Thanks to those techniques, however, the yield can reach 1,200 Kg/ha when annual rainfall is above average. Farmers are not obliged to sell their animals to purchase grains to feed their families. |
|
Use Renewable Resources Soil and water conservation techniques are very appropriate for natural resources management in the Sahelian area: underground water stock is renewed, natural vegetation is conserved (shrubs and trees do not die), and land is conserved because erosion is reduced. Minimize Toxics Applying the soil and water techniques includes adding organic mater (compost or manure) to the soil every year. In this way all risk of toxicity is avoided. Conserve Resources Runoff and erosion are reduced and rainwater can infiltrate. Farmers are no longer obliged to give up some of the crop species they used to grow and natural vegetation is conserved and/or reconstituted. Manage Ecological Relationships The techniques use only local materials: stones and organic matter. In the restored zipelle, abundant grass can grow and be grazed by cattle or when it is cultivated, crop residues are also used to feed animals. Adjust to Local Environments The Zai system is based on indigenous knowledge and the other techniques developed fit very well to the local environment. Diversify The techniques enable farmers to diversify their cropping system: crops formerly abandoned such as rice can be grown again. Many farmers grow vegetables during the dry season, thanks to water collected and stored in dams and boulis. Empower People Before the development of soils and water saving techniques, people of Yatenga province were obliged to emigrate to the southwest of Burkina Faso or to COTE D' IVOIRE to escape from drought. Nowadays some of the former migrants have returned to their native village. Manage Whole Systems Stony lines are realized both down-stream in the cultivated land and up-stream in non-cultivated lands. Maximize Long-Term Benefits The techniques enable farmers to practice sustainable agriculture. Value Health Thanks to the techniques, starvation or famine can be eradicated in this area. Medicinal plants can also be restored. |
|
|
