Impact of Limestone Deposit Operation on the Yield of Surrounding Agricultural Land: Case of the Western Rif, Morocco

Abstract

The exploitation of the limestone deposit is carried out in the open air. Its exploitation process has obvious effects on its environment, and in particular on agricultural production in neighboring lands, by suspending fine particles of matter in the air, which can potentially settle in the soil and the water. The latter being essential resources in the agricultural production process. The analysis of the quality of these resources located near the exploited zone as well as in a control zone (reference zone), both located at the level of the mountain of Haouz, of the western Rif, made it possible to assess the ’impact of the exploitation of the limestone deposit on the physico-chemical characteristics of soils and surface water. Soil and water samples were taken in these areas. The results of these analyzes made it possible to assess the level of soil fertility at each identified sampling point, as well as the characterization of surface water intended for irrigation. The results revealed that this exploitation leads to a significant modification of the soil profile of the neighboring agricultural lands, making them less fertile. This exploitation also causes a hardening of the surface layer of the soil, favoring the phenomenon of encrustation of the soil. The only positive point is that surface water is endowed with essential nutrients such as magnesium and phosphorus originating from the dust emitted during the extraction of limestone. An excessive presence of suspended matter could be accompanied by an increase in pH and thus promote the phenomenon of encrustation of soils when they are irrigated. This reveals that the exploitation of the deposits has generally negative physical and chemical impacts on the soil and consequently on agricultural production.