Effects of solarisation on soil thermal-physical properties under different soil treatments: a review

Solarisation technology allows for improving soil quality as well as crop productivity. The influence of the properties and method of use of plastic materials used to cover soils, such as the number and thickness of layers, and colour of the material, significantly alters soil thermal-physical properties. These effects can be managed and modified to increase solarisation efficiency by achieving a decrease in vapour movement between the soil surface and the atmosphere. Also, soil solarisation establishes microclimates that increase the effectiveness of fertilisers, thus modifying the soil thermal-physical properties. However, there is a lack of complete and general overview of this widely used technology. This paper presents a comprehensive review of soil solarisation technology and describes the impacts it has on soil thermal-physical properties when combined with different soil treatments. It is well-known that the efficiency of solarisation technology increases with temperature. However, we describe that the heat transfer effectivity depends on several different soil thermal-physical properties such as the soil thermal flux, conductivity, diffusivity, soil volumetric heat capacity, and soil temperature. Other soil physical properties such as soil texture, soil bulk density, soil porosity, and soil volumetric moisture content have contributions to make. Moreover, there are several external factors which significantly modify the effectiveness of heat transfer under different solarisation conditions, particularly the weather conditions, the type of tillage management, properties of plastics used and moisture content. We conclude that more research needs to be done: (i) to quantify the degree to which soil thermal-physical properties affect soil solarisation technology, and (ii) to assess the impact of soil technology on crop productivity and quality.