conservation
noun [ U ] uk/ˌkɒn.səˈveɪ.ʃən/ us/ˌkɑːn.sɚˈveɪ.ʃən/
B2 （对动植物、自然地区、历史建筑等的）保护
the protection of plants and animals, natural areas, and interesting and important structures and buildings, especially from the damaging effects of human activity
wildlife conservation 野生生物保护
a conservation area 保护区
C1 （对自然资源等的）保护，保存，节约
carefully using valuable natural substances that exist in limited amounts in order to make certain that they will be available for as long a time as possible
the conservation of coal/gas/oil reserves 煤炭／天然气／石油储量的保护
Energy conservation reduces your fuel bills and helps the environment. 节省能源能减少你的燃油费，而且还有利于环境。