preservation
n
保存；保管
The old building is in good preservation.
这栋旧建筑保存得很好.
保持；维持
the preservation of world peace
维持世界和平
conservation
n.
The act or process of conserving.
保护的行为或过程
Preservation from loss,damage,or neglect:
保存保存以避免丢失、损坏或疏忽：
Valuable manuscripts were saved from deterioration under the program of library conservation.
在图书保存计划的实施中,许多珍贵的手稿从破坏中被抢救出来
The controlled use and systematic protection of natural resources,such as forests,soil,and water systems.
保护自然资源对森林、土壤及水利系统等自然资源的有节制的使用及系统的保护
The maintenance of a physical quantity,such as energy or mass,during a physical or chemical change.
守恒在物理或化学变化过程中能量或质量等物理数量的维持原状
其实这两个词意思及其相近 互换几乎没什么问题 上面的例子可以帮助你了解其中细微差异