9DEBELL S D,CLENDENEN G W, HARRINGTON C A. Tree growth and stand development in short rotation Populus plantings:7-year results for two clones at three spacings[J]. Biomass and Bioenergy,1996,11:253- 269.
10CHRISTIAN A,ERIC D L.. Bioenergy and land-use competi tion in Northeast Brazil[J]. Energy for Sustainable Develop- ment,2000,4(3) :64-66.