Rainfall variability in the Tillabéri region is the result of significant vulnerability, which has been observed for decades. The aim of this study is to highlight the adverse socioeconomic and environmental effects of these rainfall deficits. The methodological approach used in this study included assessing farmers’ perceptions of climate change indicators through field investigations, analysing variations in temperature, relative humidity and rainfall indices in the area to better characterise the climate. The results show a low level of education among the farmers surveyed and a good perception of the effects of climate change. Rainfed and irrigated agriculture are the main economic activities in the region (99.3%), with livestock rearing and market gardening as secondary activities for 31.3% and 18.7% of respondents respectively. Access to inputs (50.8%) and agricultural credit (10.3%) are major assets for producers in the area, in addition to their experience of new agricultural technologies (62%). The most significant inter-annual peaks in rainfall indices were observed on the following dates: 09/25/1988, 03/01/199, 05/18/2004, 08/05/2009 and 01/10/2020. However, inter-annual variations are also observed (09/25/1988 and 01/10/2020). The indicators of environmental change as perceived by farmers are bare soil (77.3%), gravelly soil (9.7%), erosion gullies (7%), silting up of fields (8.7%) and proliferation of Striga sp. (7%). The reduction in herbaceous plants (30.7%) and the drying out and mortality of woody plants (20.3%) are visible signs of land degradation on natural vegetation. The main causes of these changes are reduced rainfall (82%), the action of strong winds (37.3%), water erosion (34%) and intensive deforestation (24.3%). To these must be added harmful agricultural practices such as the absence or reduction of fallow periods, bush fires, low inputs of organic and mineral fertilisers, low use of CES/DRS techniques, etc. The natural vegetation cover (woody and herbaceous) that used to protect the soil has declined sharply, leaving it vulnerable to erosion.

Leptadenia hastata is a wild edible plant that is highly prized for its culinary and economic value. It is also a medicinal plant very exploited by the Nigerien population. These multiple uses due to harsh climatic conditions put enormous pressure on the species’ stands, which limits its natural regeneration. The present study, conducted in the laboratory of life and earth sciences of the «Ecole Normale Supérieure» of Abdou Moumouni University of Niamey, aims to evaluate the effect of three pretreatments on the germination of two batches of Leptadenia hastata seeds in the laboratory: seeds kept at room temperature in the laboratory for two months (recent seeds) and seeds kept at room temperature in the laboratory for sixteen months (old seeds). In order to assess the latency time, duration, speed and germination rate according to age, the two batches of seeds were subjected to three different pretreatments: seeds soaked in tap water for 12 hours; seeds soaked in tap water for 6 hours; and seeds that did not undergo any pretreatment and were considered as controls. The best latency time and the shortest germination speed are obtained with the recent seeds soaked for 12 hours. But these seeds recorded the lowest germination rate 88.66%. The best germination rate is obtained with the older seeds soaked during 12h (100%), followed by the control old seeds and recent seeds soaked during 6h (98.66% each). The shortest germination time (9 days) was obtained with recent seeds soaked for 6h.