Plants are capable of both, physical and chemical weathering of rocks. Plants grow on rocks and their roots, while growing, enters the cracks within the rock and extend them. Over time, large enough cracks develop and weathering takes place. Plants, such as moss, are capable of releasing weak organic acids, that will dissolve minerals from the rocks and cause chemical weathering. Apart from moss, organisms such as fungus and lichen are also capable of similar chemical weathering action. This acid causes breaks down the minerals and provides the nutrient for plants and organisms. In some cases, roots of decaying plants may also release chemicals that will accelerate the weathering process. Plants also condition the soil (which is formed from broken rocks) and ensure that the soil would be able to support their growth.
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