Examining temperature and soil moisture contents of mulches in the urban landscaping of an arid region

Abstract

High temperatures, low average rainfall, drought, and high evapotranspiration are limiting factors in arid lands. Therefore, when constructing landscapes (green spaces) in these regions, strategies should be developed to mitigate these climatic influences. One practical strategy is utilizing different types of mulches on the surface of the soil. This study was conducted as a randomized complete block design experiment with four replications during 2014 and 2015 to examine the performance of organic and inorganic mulches as non-living mulches and ground cover plants as living mulches. Ground cover plants were Carpobrotus sp., Potentilla reptans, Vinca minor, Frankenia sp. and a mixed turfgrass. Non-living mulches were turfgrass clippings, wood chips, sawdust, gravel, rubble and scoria (volcanic rock). Bare soil was used as the control treatment. The results demonstrated the application of mulches could modify soil temperature at 5 and 15 cm depths in different seasons of the year. The living mulches especially Carpobrotus sp. and turfgrass reduced the temperature more than the non-living mulches. The soil covered with sawdust and wood chips preserved soil moisture content over the soil covered with other types of mulches. It would appear the selected mulches could decrease the irrigation intervals through increased water holding capacity of the soil. The outcomes of this research could assist landscape managers operating in extreme climate conditions of arid and semi-arid regions to advance the management of soil moisture and temperatures with the objective to improve sustainability.

Keywords

• mulch
• soil temperature
• organic
• ground cover
• green space