In arid and semiarid areas,water uptake (non-rainfall water) serves as an important water source for plants,biological soil crusts,insects and small animals.In this study,a measurement program was undertaken to investigate water uptake and its changes during formation of man-made algal crusts in the Qubqi Desert.In the study region,water uptake from the atmosphere accounted for 25.07%-39.83% of the total water uptake,and was mainly taken up by a water vapor adsorption mechanism;the proportion of water uptake from the soil substrate was much higher (60.17%-74.93%).The formation of crusts promoted water uptake,but the increased uptake did not occur immediately after inoculation or crusts formation.The water taken up from the atmosphere increased significantly from day 15 after inoculation,and the soil water content was markedly enhanced from day 20 after inoculation.It is considered that the growth of algal filaments and their secretions were the main factors increasing the amount of water uptake and water content in the crusts,and these variables increased even during dry periods when some algae are likely to have died.
LAN ShuBin1,2,HU ChunXiang1*,RAO BenQiang1,2,WU Li1,2,ZHANG DeLu1,2 & LIU YongDing1 1State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China
