Human activities have gradually damaged the land-water ecosystem, and natural processes, in turn, produce grievous losses to human society. Numerous environmental laws have been enacted to safeguard people and their investments from pollution and other forms of air, water, and land degradation. There have also been massive environmental changes in the twentieth century. These have been produced by a combination of urbanization, population growth, production of new machines rapidly increasing fuel consumption. An important objective of environmental research work and study should be directed to determine which types of plant construction and resource extraction methods minimize damages to the land-water ecosystem. This objective must be linked to attempts to understand and find solutions to the environmental problems that exist, whether rfatural or the result of human activities.

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