Chemical weathering is the process of weathering or break down of rocks, soil, etc. by chemical reactions. These reactions include hydrolysis, carbonation, hydration, dissolution, etc. Human actions modify these chemical weathering processes. An example is hydrolysis of feldspar by rainwater, which results in formation of clay and subsequent weakening of granite rocks. Human intervention, in terms of concrete pavement and paved channels, ensures that rainwater does not seep into the ground anymore, but is collected and transported to a new location. It can also be harvested by rainwater collection systems and reused. The rainwater will no longer enter the subsurface and lack of rainwater means no hydrolysis of feldspar and hence no chemical weathering of it. More plants, trees or artificial capture of atmospheric carbon dioxide will reduce the availability of CO2 for carbonation, thereby further altering the chemical weathering process.
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