自然环境保育（Preservation of the natural environment） (a)处理有机废弃物：食物残肴与人体排泄物可制成肥料，做为种植作物之有效 用途。
双语例句
1
Environmentalists are people who advocate thepreservationofthenaturalenvironment.
环境主义者是倡导保护自然环境的人。
2
Chapter two analyzes the city, s natural and social environment, s historical changes and the city, s structure, s transformation, and points out the present problems in the preservationof the city.