中国煤炭铁路运输生命周期温室气体排放研究
张优, 程明今, 刘雪薇

Life cycle greenhouse gas emissions from China’s coal railway transport
ZHANG You, CHENG Mingjin, LIU Xuewei
图2 铁路运输温室气体排放的系统边界
Figure 2 System boundary of the greenhouse gas emissions from railway transportation