conservation of mass

careful result of research [done/conducted] by Dodi Supriadi ( 1998) concluded that value of intangible prima facie protected forest [of] him as penyedia of water have economic value six times bigger than wood value, even totalize benefit value of intangible forest ( recreation plus, environmental quality and wildlife) will be bigger progressively again.

In this time many researcher have [done/conducted] various research to connect treatments of forest to behavior of hidrologi. Matter which have been accepted in general [is] that usage of vegetasi [cover/conclusion] of forest will be able to improve;repair current fluctuation ( Seyhan, 1990). Facing various fact above hence attention of people start to look into forest as a(n) system prop of life and [do] not only as wood producer. Forest with its wide [of] spreading, with structure and [his/its] immeasurable composition can provide very big benefit to human life for example protection service to floods, erosion, sedimentation and slide farm.