Morocco

Climate change significantly challenges the sustainability of forest ecosystems, with broad socio-ecological impacts insufficiently assessed. This study examines one such critical system, the Globally Important Agricultural Heritage Systems (GIAHS), focusing on preserving the Argan tree in the Ait Souab-Ait Mansour region of southern Morocco. The region, including the Massa and Tamanart river basins, is crucial for Argan tree conservation, yet there is limited information on how climate change will affect the tree. This study aims to analyze climate variability trends and potential impacts on Argan tree distribution using observed (1983–2022) and projected rainfall and temperature data up to 2080. The MaxEnt model projected Argan tree distribution for 2041–2060 and 2061–2080 under four scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5). Findings reveal significant climatic disparities, with warming of 0.4 C between 1983 and 2022 and future temperatures reaching up to 4 C between 2041 and 2080. Rainfall shows considerable variability, with a decrease of approximately 2.5 mm per decade during the rainy season. Projections indicate a decline in annual precipitation, impacting seasonality and increasing the frequency of extreme events during the argan fruit production season. Suitable areas for Argan trees are expected to decline, particularly in the Tamanart and Massa River basins. The study highlights a 47–65% reduction in highly adapted zones in the med term (2041–2060), and 49–81% in the long term (2061–2080), emphasizing the need for proactive adaptation measures in effort to conserve and increase Argan tree’s survival and productivity.

The concept of integrated water resource management requires an in-depth analysis of water inflows into a river basin. Population growth and the uncertainties associated with climate change are causing increased water stress and droughts, which are impacting agriculture. Hence the need for studies on the impact of climate change on demand-supply interactions in river basins. In this study, a generic decision support system, ModSim, was used; for the first time in the region; to examine the agricultural water usage and demands over Souss basin in Morocco. ModSim was calibrated over the period from 1990 to 2019 using recorded data about physical processes and hydraulic infrastructures features and management. The simulations succeeded in replicating different deficit episodes at the various irrigated perimeters. During the simulated period from 2012 to 2019, it was observed that the water supplies for the different dams in the basin experienced a decline ranging from 38% to 89%. As a result, the average total unmet demand for surface water from reservoirs in irrigated areas reached 201 mm3 between 1990 and 2019 and the monthly average demand increases by 55% in the dry season, compared to the demands in the rest of the year. The significant amount of unmet demand across all sites suggests that demands are satisfied by the withdrawal of water from groundwater resources. The adopted approach has proven to be a useful decision support tool to understand water resources planning challenges. Water managers require such reliable tools to represent the basinapos;s water trade-offs. Thus, additional investigation to improve the representation of groundwater/surface water interaction approaches is required to enhance the evaluation of the consequences of different uses, especially in arid and semi-arid regions with significant water stress such as Souss. A conceptual framework as well as a detailed discussion have been produced in order to guide efficient water management and governance.