@article{杨学明_710, author = {[杨学明, 张晓平, 方华军, 梁爱珍]}, title = {20年来部分黑土耕层有机质和全氮含量的变化}, publisher = {地理科学}, year = {2004}, journal = {地理科学}, volume = {24}, number = {6}, eid = {710}, pages = {710-714}, keywords = {黑土;有机质;全氮;历史变化}, doi = http://geoscien.neigae.ac.cn/CN/10.13249/j.cnki.sgs.2004.06.710 }