Effect of soil crust on evaporation and dew deposition in Mu Us sandy land, China

Abstract

The development of soil crust on sandy land may affect the surface hydrological process. This paper investigates the process of evaporation and dew deposition influenced by different soil surface types which were dominated by sand, primitive biotic crust, and advanced biotic crust, respectively, in the south fringe of Mu Us sandy land in Northwest China from July to September of 2006. The experimental results indicate that the advanced biotic crust could increase evaporation and dew deposition compared to the primitive biotic crust and bare sand although the differences between them were not significant. The average evaporation from advanced biotic crust, primitive biotic crust and sand was 6.8, 6.6, and 6.5 mm/d, respectively, and water content is around 16.2 % in the condition of initially identical soil. The average dew amount on advanced biotic crust was 0.116 mm/d with extreme 0.05 and 0.24 mm/d. The average values on primitive biotic crust and sand were 0.105 and 0.101 mm/d, respectively, with extreme 0.04 and 0.21 mm/d for both treatments. Also, the dew deposition on advanced biotic crust seemed stable and might rest for a longer time than that on primitive biotic crust and sand. The results suggest that the advanced biotic crust possibly facilitates evaporation and dew deposition. Therefore, the development of biotic crust may potentially enhance the hydrological circulation in the upper sand layer in sandy land.

Measurements and ecological implications of non‐rainfall water in desert ecosystems—A review

“…As shown above, with greater distance from ground, fruticose lichens, which protrude up to several centimeters above ground, are much more likely to condense vapour. Similar pattern, with NRW exhibiting low amounts on sand and high amounts on moss-dominated crust (with intermediate values at the cyanobacterial crust) was also obtained by other scholars (Colica et al, 2014;Jia et al, 2014;Li et al, 2013;Liu et al, 2006;Ouyang et al, 2017;Pan et al, 2010;Sun et al, 2008;Uclés et al, 2016;Wang et al, 2014;Xu et al, 2013;Zhang et al, 2009Zhang et al, , 2010. Similar pattern, with NRW exhibiting low amounts on sand and high amounts on moss-dominated crust (with intermediate values at the cyanobacterial crust) was also obtained by other scholars (Colica et al, 2014;Jia et al, 2014;Li et al, 2013;Liu et al, 2006;Ouyang et al, 2017;Pan et al, 2010;Sun et al, 2008;Uclés et al, 2016;Wang et al, 2014;Xu et al, 2013;Zhang et al, 2009Zhang et al, , 2010.…”

“…A lower impact of the soil heat flux also explained the higher amounts and longer duration (by 50-70%) of NRW on mossdominated crusts in comparison to the cyanobacterial crusts (Kidron et al, 2002a). Similar pattern, with NRW exhibiting low amounts on sand and high amounts on moss-dominated crust (with intermediate values at the cyanobacterial crust) was also obtained by other scholars (Colica et al, 2014;Jia et al, 2014;Li et al, 2013;Liu et al, 2006;Ouyang et al, 2017;Pan et al, 2010;Sun et al, 2008;Uclés et al, 2016;Wang et al, 2014;Xu et al, 2013;Zhang et al, 2009Zhang et al, , 2010.…”

Dew formation characteristics at annual and daily scale in xerophyte shrub plantations at Southeast margin of Tengger desert, Northern China

“…So, as an important alternative water source to rainfall in arid areas, the ecological significance of dew cannot be neglected, which serves as an important source of moisture for plants, biological soil crusts (BSCs), insects, and small animals, especially in desert environments, where water resources are limited (Jacobs, Heusinkveld, & Berkowicz, ). Water vapour exchange at the earth's surface has been receiving increasing attention, and recent research has also identified its importance to local water balance in arid and semiarid environments during certain periods of the year (Jacobs et al, ; Moro, Were, Villagarcía, Cantón, & Domingo, ; Sun et al, ). As an important water source, dew plays a role in physiological activities of the plant.…”

“…As an important water source, dew plays a role in physiological activities of the plant. Dew can facilitate seed germination (Gutterman & Shem-Tov, 1997), improve photosynthesis (Rao et al, 2009), mediate water status in plants under water stress (Munné-Bosch & Alegre, 1999), and provide moisture directly to leaves and BSCs (Stone, 1957;Sun et al, 2008). Furthermore, dew plays a role as a source of moisture in the stabilization of sand dunes (Subramanian & Kesava-Rao, 1983) and revegetation restoration (Zhuang & Zhao, 2014).…”

Sources of monsoon precipitation and dew assessed in a semiarid area via stable isotopes

“…Dew originates from atmospheric humidity and the condensation of water vapor on a surface by means of (passive) radiative cooling (Monteith, ; HMSO, ; Beysens, ; Youhua, Zhou, & Song, ., Sun, Xiaoyan, Heye, Yang, & Tang, ). Usually, dew has been considered a minor component of the water balance; however, much research has indicated that dew played an important role in the local water balance in arid and semiarid environments during certain periods of the year (Jacobs, Heusinkveld, & Berkowicz, ; Moro, Were, & Villagarcía, ; Sun et al, ). Dew generation and frequency were often greater than those of precipitation (Jacobs, Heusinkveld, & Berkowicz, ) and affected the energy balance between the soil, plants, and the atmosphere (Agam & Berliner, ).…”