Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), Ben Guerir 43150, Morocco.
Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), Ben Guerir 43150, Morocco; Department of Geology, Faculty of Sciences-Semlalia, Cadi Ayyad University, Marrakech 40001, Morocco.
Sci Total Environ. 2022 Aug 15;834:155328. doi: 10.1016/j.scitotenv.2022.155328. Epub 2022 Apr 19.
Mediterranean piedmonts are an important hydro-agricultural systems. They constitute the junction between the mountains, where the streamflow is generated, and the surrounding plains, where the water is used. In Morocco, these traditional systems extend largely along the High Atlas Mountains. Yet, changing conditions in the Mediterranean basin as well as recurrent droughts in recent decades remain poorly understood in terms of hydrological and agricultural impacts, particularly in traditional hydro-agro-systems. The combined effects of climate variability and ineffective management of water resource dynamics may lead to increased water scarcity in these regions. The present work aims to assess the effects of climate variability and associated agricultural changes on water resources in a traditional irrigated piedmont of the Moroccan High Atlas. To that end, a trend analysis, together with change points detection, was carried out on annual and monthly precipitation, and streamflow from 1965 to 2018. Then, the standardized precipitation index (SPI) was employed to identify meteorological droughts. Also, groundwater, and spring discharge data were analyzed and discussed from 1973 to 2021. SPI outcomes revealed three major droughts, in 1981-1988, 1999-2008, and 2013-2018. Although the precipitation data showed no significant trend, except for Tahannaout station, the average annual precipitation over the piedmont area decreased by 28%. Similarly, streamflow decreased significantly by almost 40% for all stations, as did the Abainou spring's discharge. Consistent with that, groundwater level has declined dramatically over the past decades in the downstream piedmont. These decreases in water cycle components were tightly aligned with droughts. Yet, irrigation diversions were maintained in both dry and wet periods. Paradoxically, this decrease in water resources was associated with an agricultural transition from seasonal crops (cereals) to perennial crops (olive trees). This conversion is likely to amplify the water shortage, leading to groundwater resources overexploitation to satisfy the growing agricultural demand.
地中海山麓地区是重要的水-农业系统。它们位于山区和周围平原的交界处，山区是水流的发源地，平原则是水流的利用地。在摩洛哥，这些传统系统主要沿着高阿特拉斯山脉延伸。然而，地中海盆地的变化条件以及近几十年来的频繁干旱，在水文和农业影响方面仍未得到充分理解，尤其是在传统的水-农业-系统中。气候变异性和水资源动态管理不善的综合影响可能导致这些地区的水资源更加短缺。本研究旨在评估气候变异性和相关农业变化对摩洛哥高阿特拉斯传统灌溉山麓地区水资源的影响。为此，对 1965 年至 2018 年的年际和月际降水和流量进行了趋势分析和突变点检测。然后，利用标准化降水指数（SPI）来识别气象干旱。此外，还分析和讨论了 1973 年至 2021 年的地下水和泉水流量数据。SPI 结果显示，该地区发生了三次主要干旱，分别发生在 1981-1988 年、1999-2008 年和 2013-2018 年。尽管降水数据除 Tahannaout 站外，没有显示出明显的趋势，但山前地区的年平均降水量减少了 28%。同样，所有站点的流量都显著减少了近 40%，Abainou 泉的流量也减少了。与此一致的是，过去几十年来，下游山前地区的地下水位急剧下降。这些水循环组成部分的减少与干旱密切相关。然而，无论是在干旱还是湿润时期，灌溉引水都得到了维持。矛盾的是，这种水资源的减少与从季节性作物（谷物）到多年生作物（橄榄树）的农业转型有关。这种转变可能会加剧水资源短缺，导致地下水资源过度开采，以满足不断增长的农业需求。
