Shallow wells, the untapped resource with a potential to improve agriculture and food security in southern Mali

Abstract

Background: Excessive rainwater during the rainy season and lack of water in the dry season have been challenging the agricultural productivity and food security for rural communities in southern Mali. Various soil and water conservation practices were implemented in the past to improve crop yields and income, and reverse the effect of land degradation. However, none of these efforts looked into the potential use of shallow wells at a spatial scale to improve the agricultural productivity and hence the food security in the region. Results:In total 484 shallow wells were geo-referenced, mapped and studied in two districts, Bougouni and Koutiala, in southern Mali to understand the dynamics of groundwater recharge and relationship with rainfall in different seasons. The study found out that shallow wells were mainly utilized for household and livestock water consumption and not for agricultural water use. Well construction history followed the trend of the severe drought that hit the Sahel in the years of the 1970s and 1980s. Majority of wells (87 % in Bougouni and 84 % in Koutiala) were constructed after the drought period with significant variation of construction in the two districts (p value 0.032). Well depths ranged from 1 to 150 m, with the majority of wells (64 %) within the depth range of 6.5-14.5 m (p value 0.043). During the dry season water was available in the majority of wells (73 %) at a depth range from 5.5 to 15.5 m (p value 0.996). In the rainy season on average 84 % of wells in Bougouni and 94 % of wells in Koutiala experience water level rise within the range of 0.5-10.5 m (p value 0.423/Bougouni and 0.991/Koutiala). In few of the studied villages shallow wells were found to be fast recharging, thus enabling farmers to buffer the negative effects of drought conditions. Conclusion:Shallow wells are important sources of water in rural Mali. The wells have adequate recharging capacity during the rainy season and insignificant water level variation during the dry season. Though accessing water from shallow wells was labour-intensive and mostly done by women and the youth, water is available within an average depth ranging from 5.5 to 15.5 m from most studied wells. The issue of water scarcity in different seasons was thus attributed to accessibility due to the lack of appropriate water lifting mechanisms. Groundwater was an untapped resource in Mali, and we suggest groundwater management needs to be given consideration along with other management practices in the changing climate condition to improve the agricultural productivity and food security.

Solar-based irrigation systems as a game changer to improve agricultural practices in sub-Sahara Africa: A case study from Mali

“…Environmental factors (land use and land cover, distance to urban/ rural areas) and economic factors (distance to the road, slope, distance to river, population density) were sourced from the Malian national GIS database available at the Institute of Rulale Economy (IER). Groundwater level data was sourced from previously georeferenced databases of Birhanu and Tabo (2016) and the spatial records of IWMI (2019). The collected spatial data at different scales were brought together using GIS software and re-scaled to make the output at a district level.…”

“…The vegetable gardens, though limited in scope, allow diversification of food in the household, leading to an increased household income. Traditional irrigation is practiced using shallow wells that have depths ranging from 6.5 to 14.5 meters (Birhanu and Tabo, 2016). A recently conducted survey on water availability and access in rural Mali revealed that while 39% of rural Malians always lack water, periodic water shortages are experienced by the majority of communities (61%) (Sanogo et al, 2021) sometimes or the other.…”

“…For example, the Feed the Future Innovation Lab for Small-Scale Irrigation (ILSSI), the CGIAR Research Program on Water, Land and Ecosystems (WLE), and the Africa Research In Sustainable Intensification for the Next Generation (Africa RISING) benefitted farmers for domestic water supply and smallscale irrigation practices (IITA and ILRI, 2018;Gadeberg, 2020). In their study of georeferencing 484 shallow wells in southern Mali, Birhanu and Tabo (2016) highlighted that the issue of water scarcity in most rural Mali was attributed to accessibility due to the lack of appropriate water-lifting mechanisms. Other studies (DNH, 2016) also confirmed that extraction and use of groundwater resources for irrigation have been very low in most places of rural Mali.…”

Soil Erosion Control and Moisture Conservation Using Contour Ridge Tillage in Bougouni and Koutiala, Southern Mali

“…Average bulk density is 1.5 g•cm 3 at 0 -20 cm soil horizon. These soils are inherently fragile with weak water retention capacity and poor in plant nutrients [12]. Soil pH varied from moderately acid (pH 2 O = 6.5) to acid (pH 2 O = 5.5), Organic Carbon (5 -6 g•kg −1 ), Nitrogen (<0.5 g•kg −1 ), available P (<0.07 g•kg −1 ), exchangeable K (<72 mg•kg −1 ), Cation Exchange Capacity (CEC) (4 -6 cmol•kg −1 ) and a base saturation ratio 75%.…”

“…[11] concluded that 44% of farmer's agricultural incomes losses are due to soil depletion which is a major factor influencing food security in the area and finally the economy of the country since it affects the main rainfed staple crop. According to [12], the major staple crops grown in southern Mali are millet (Pennisetum glaucum (L.) R. Br.…”