One of the most important subjects in relation of water resources quality in the many of river is the chemical composition of waters and conservation of water quality in the watershed. Geological formations in any region of the earth are the main surface and foundation that water flows on the bed and strata of formation, which in fact they affect their characteristics on water quality as positi...

VANCI-AY'J.IL 1989. Modelling selection harvesting in tropical rain forests. Long term yield estimates for natural forests require a harvesting model to enable future yields to be estimated reliably. The model should predict the felled stems, the proportion of these which are merchantable, and any damage to the residual stand. Regression analyses was used to develop a model of current logging p...

• Background • Acid Rain & Cars • Acid Rain & Forests • Acid Rain & Health • Acid Rain & Water • Acid Rain in Europe • Acid Rain in US • Acid Rain Study The ecological effects of acid rain are most clearly seen in the aquatic, or water, environments, such as streams, lakes, and marshes. Acid rain flows to streams, lakes, and marshes after falling on forests, fields, buildings, and roads. Acid r...

low cereal and legumes yields and their rwp index are mainly due to poor distribution of rainfall and poor agronomic management practices. rainfed barley yield and rain water productivity (rwp, defined as rainfed grain yield divided by the total crop season annual rainfall water) in the dry farming are considerable by topography and latitude. yield data, rainfall, altitude and latitude of 182 p...