Impacts of Market Gardening Practices on Environmental Resources: The Case of Irrigable Lands in Bonkoukou (Imanan Rural Municipality, SW Niger Republic)

Abstract

Due to increasingly extreme climatic conditions in the Sahel, irrigated crops are emerging as imperative innovations for agricultural transformation and resilience. This study is designed to assess the impact of market gardening on soil, water and plant cover in the western Niger Republic. Semi-structured survey data were collected from 78 site operators in the Imanan rural municipality (Filingué, Tillabéry). In addition to the survey, a photographic collection illustrated certain observable facts in the field. The survey shows that the wooden enclosures (70.65% of respondents) around the fields are renewed every year. The impacts are then substantial: deforestation of plateaus, clearing of valleys for new extensions, loss of wildlife habitat, changes in the water flow regime resulting from a geomorphological change in the commune. Itou, the preparation of the planks consumes a lot of water. Thus, the new sinking of water points and the load pressure increase the drawdowns of wells and boreholes in the sites (75.46% of respondents). The frequent spills of waste oil on the sites, as well as the numerous potato storage pits, are among the factors and vectors most likely to contaminate the soils and aquifers of the study area. Market gardening destabilizes the soils and induces regressive erosion as well as area runoff of rainwater on all sites and on the slopes. On the other hand, slash-and-burn practices, drying of branches intended for fences, as well as rain-fed cowpea crops, promote improved physical properties and soil fertilization. To reduce the risks of disintegration and especially of silting up of sites, the study suggests a policy of live hedges and wire fences so that common spaces can be imposed on operators.