http://reply.papertrans.cn/2/145/14426/14426-31.png
Submitted on: 22 October 2000.
Revised on: 23 January 2001.
Accepted on: 09 March 2001.
___________________International Soil and Water Conservation Research
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Submitted on: 07 November 2015.
Revised on: 16 January 2016.
Accepted on: 27 February 2016.
___________________International Soil and Water Conservation Research
Submitted on: 26 June 1998.
Revised on: 05 October 1998.
Accepted on: 11 November 1998.
___________________International Soil and Water Conservation Research
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