http://reply.papertrans.cn/2/101/10032/10032-31.png
http://reply.papertrans.cn/2/101/10032/10032-32.png
http://reply.papertrans.cn/2/101/10032/10032-33.png
Submitted on: 15 February 2009.
Revised on: 17 April 2009.
Accepted on: 04 May 2009.
___________________Forests Trees and Livelihoods---TAYLOR & FRANCIS LTD
http://reply.papertrans.cn/2/101/10032/10032-35.png
Submitted on: 14 January 1998.
Revised on: 23 March 1998.
Accepted on: 19 May 1998.
___________________Forests Trees and Livelihoods---TAYLOR & FRANCIS LTD