1. College of Resources and Environment, Qingdao Agricultural University, Qingdao, P. R. China
2. Qingdao Engineering Research Center for Rural Environment, College of Resources and Environment, Qingdao Agricultural University, Qingdao, P. R. China
3. College of Landscape Architecture & Forestry, Qingdao Agricultural University, Qingdao, P. R. China
4. Department of Soil Science and Soil Water Conservation, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan