conservationaladj.保存的；守恒的；；油封的conservationn.保存；保护；守恒；节约conservation of energy metabolism无创conservation of historic district历史街区保护conservation of mechanical energy机械能守恒conservation forest gene resource森林基因资源保护conservation- conscious society节约型社会conservation of historic building城市历史建筑保护Conservation of historic heritage历史遗产保护Conservation and re-utilization保护和再利用conservation - oriented society节约型社会conservation of natural resources自然资源保护,自然资源守恒