Importance of diversity in the functioning and structure of riverine communities

The natural diversity of biological communities provides many alternative pathways by which nutrients and energy may move through ecosystems. Many different species are capable of performing similar functional roles in nature. When disturbed or polluted, natural systems often become restored first through the activities of species that had not previously been common. Human activities often result in reduction or loss of diversity within ecosystems, particularly through the loss of rare species. Maintenance of diversity is vital because it provides protection against both natural and human‐caused catastrophies.