共 7 条
[3]
Optimizing the external energy input into farmland ecosystems: A case studyfrom Ningxia, China. Ma Z Y,Edwards-Jones G. Agricultural Systems . 1997
[6]
Energy Equivalents of Network Inputs to Food Product:on Process. Leach G,Slesser M. . 1973
[7]
Analysis of energy use of energy in agriculture-Approaches and problems. Jones NI R. Agricultural Systems . 1989