In contrast to the natural environment is th. Built environments are where humans have fundamentally transformed landscapes such as urban settings and agricultural  , the natural environment is greatly changed into a simplified human environment. Even acts which seem less extreme, such as building a mud or a  in the he modified environment becomes an artificial one. Though many animals build things to provide a better environment for themselves, they are not human, hence , and the works of  are thought of as natural.

People cannot find absolutely natural environments on Earth, and naturalness usually varies in a continuum, from 100% natural in one extreme to 0% natural in the other. The massive environmental changes of humanity in the  have fundamentally effected all natural environments: including from   and pollution fromand  in the  and  More precisely, we can consider the different aspects or components of an environment, and see that their degree of naturalness is not uniform.If, for instance, in an agricultural field, the  and the  of its soil are similar to those of an undisturbed forest soil, but the structure is quite different.Humans impact the water in different ways such as modifying rivers (through and ),   These impact lake levels, groundwater conditions, water pollution, thermal pollution Humans modify rivers by using direct channel manipulation.We build dams and reservoirs and manipulate the direction of the rivers and water path. Dams can usefully create reservoirs and hydroelectric power. However, reservoirs and dams may negatively impact the environment and wildlife. Dams stop fish migration and the movement of organisms downstream. Urbanization affects the environment because of deforestation and changing lake levels, groundwater conditions, etc. Deforestation and urbanization go hand in hand. Deforestation may cause flooding, declining stream flow, and changes in riverside vegetation. The changing vegetation occurs because when trees cannot get adequate water they start to deteriorate, leading to a decreased food supply for the wildlife in an area.

A significantly profound challenge is to identify the natural environmental dynamics in contrast to environmental changes not within natural variances. A common solution is to adapt a static view neglecting natural variances to exist. Methodologically, this view could be defended when looking at processes which change slowly and short time series, while the problem arrives when fast processes turns essential in the object of the study.