Natural and synthetic zeolites for water management in agriculture: A review

Anthropogenic pressure and climate changes are causing dramatic depletion of the availability and quality of water resources. This has a significant effect on agricultural activities which uses more than two-thirds of the renewable water resources and must respond to the increasing demand for food. In this context, retaining water in agricultural soils without influencing crop yield allows for better management of this precious resource. With this aim, many literature data have documented the application of different additives to soil and among these, zeolites have always played a leading role due to their specific properties. This article summarizes studies concerning both natural and synthetic zeolite utilization in agriculture water management. The use of these materials is investigated in detail by referring to the numerous studies published worldwide over the last decades. Many investigations have been conducted on the effect of zeolites addition in conditioning physical properties in soil, and many others concern the action of these minerals in water management for plants. However, to our knowledge, no review article has been published yet that summarizes the literature on both these aspects and shows the contradictions that characterize many research results. It is precisely the analysis of these contradictions that provides guidance for the development of future lines of research. These should be based on large-scale experiments testing the effectiveness of zeolite addition in the soil-plant binary system for water management, mainly considering grain size and mineralogical composition of soils as well as percentage and size of zeolites. Zeolite framework plays a subordinate role as does the type of culture.