A natural region (landscape unit) is a basic geographic unit. Usually, it is a region which is distinguished by its common natural features of geography, geology, and climate.[1]
From the ecological point of view, the naturally occurring flora and fauna of the region are likely to be influenced by its geographical and geological factors, such as soil and water availability, in a significant manner. Thus most natural regions are homogeneous ecosystems. Human impact can be an important factor in the shaping and destiny of a particular natural region.[2]