Infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems of Inner Mongolia, China  

作　　者：ZHANG Si-yi LI Xiao-yan PENG Hai-ying ZHANG Zhi-hua 

机构地区：[1]State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China [2]College of Resources Science and Technology, Beijing Normal University, Beijing 100875, China

出　　处：《地球环境学报》2012年第6期1117-1125,共9页Journal of Earth Environment

基　　金：National Natural Science Foundation of China （41025001, 41130640 ）;We would like to thank the anonymous reviewers for their valuable and constructive comments. The authors also wish to thank the Shuai Guan-yuan and Sun Xiu-min for assistance in the field work.

摘　　要：Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation.Water is the most critical factor for controlling the vegetation pattern in arid and semiarid regions. Using a dye-tracing experiment, we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems. The dye coverage, uniform infiltration depth, maximum infiltration depth, total stained area and heterogeneous infiltration stained area were measured by two indices, the maximum infiltration depth index （MIDI） and heterogeneous infiltration index （ HII）, which were calculated by processing dye-stained photos. The MIDI and HII of soil under shrubs were 1.41 ± 0.14 and 0.29 ±0. 068, respectively, and larger than those of grass soil, 1.26 ± 0.14 and 0.20 ± 0. 076. Using the MIDI, HII, field soil moisture and rainfall data, the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated. The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches. These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation.

关 键 词：Infiltration pattern dye-tracing SHRUB grass patches typical steppe ecosystems 

分 类 号：S152[农业科学—土壤学]