名詞 conservation:

1. an occurrence of improvement by virtue of preventing loss or injury or other change
   同義詞：preservation
2. the preservation and careful management of the environment and of natural resources
3. (physics) the maintenance of a certain quantities unchanged during chemical reactions or physical transformations

1. If I may refer back to the problem we discussed, I think we shall stress on the conservation of our natural resource.
   請?jiān)试S我重提我們剛才討論過的問題，我想我們應(yīng)該強(qiáng)調(diào)保存我們的自然資源。
2. Who discovered the conservation of energy?
   誰發(fā)現(xiàn)了能量守恒？
3. Most people have come to accept the need for conservation of natural resources.
   現(xiàn)在大多數(shù)人已認(rèn)識到保護(hù)自然資源的必要。

con.ser.va.tion

n.（名詞）
The act or process of conserving.
保護(hù)：保護(hù)的行為或過程

Preservation from loss, damage, or neglect:
保存：保存以避免丟失、損壞或疏忽：
例句：
Valuable manuscripts were saved from deterioration under the program of library conservation.
在圖書保存計(jì)劃的實(shí)施中，許多珍貴的手稿從破壞中被搶救出來

The controlled use and systematic protection of natural resources, such as forests, soil, and water systems.
保護(hù)自然資源：對森林、土壤及水利系統(tǒng)等自然資源的有節(jié)制的使用及系統(tǒng)的保護(hù)
The maintenance of a physical quantity, such as energy or mass, during a physical or chemical change.
守恒：在物理或化學(xué)變化過程中能量或質(zhì)量等物理數(shù)量的維持原狀

【引伸】
con.serva.tional
adj.（形容詞）