Impacts of Dams on Biodiversity

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Conclusion It can be easily acknowledged that all the benefits related to constructing dams favor human welfare over environmental degradation. Dams either have temporary or permanent effects on the environment, whether this effect is upstream or downstream of the dam. However the increase in human population has lead to significant over-damming. Only after scientists and governments fully understand the effect of damming on biodiversity can they minimize if not end its deleterious consequences. In hope of ending all scenarios having heavy collision on our futures to achieve a state of harmony with nature. Pros Contribute domestic water benefits Produce electric energy Introduction Dams are physical barriers that generally regulate water flow or collect water streams and retain them as water bodies. The main purposes of installing a dam is to generate electricity without releasing atmospheric pollutants or greenhouse gases, to protect against floods and to collect water (for drinking and irrigation). The damming of rivers has dramatic consequences. Whether dams are beneficial or detrimental to biodiversity and surrounding human populations has been debated since the 1960s. Impacts of Dams on Biodiversity Hussein J. Kanbar Objective Ranking the effects on biodiversity that are due to dam construction. Knowing whether dams are built for the benefit of humans or the environment. Defining the circumstances under which these mega-structures should be built. 0 40 60 80 100 20 10 6 4 2 8 -1 2 80 86 115 135 145 168 173 175 248 Eggs Density (eggs/m3) Larvae Density (larvae/m3) Downstream Upstream Reservoir 0 40 60 80 100 20 10 6 4 2 8 -1 2 28 62 86 115 145 173 180 187 248 Distance from the dam ( Km) Eggs Density (eggs/m3) Larvae Density (larvae/m3) Downstream Upstream Reservoir Spatial variation in the density (+/- standard deviation) of planktonic fish eggs and larvae in the Middle Tocantins River, before (October 1999 – September 2001 “left”) and after (October 2002– September 2004 “right”) the formation of Lajeado Reservoir. $116 million dollar lost for biodiversity’s sake And Litany Dam Water quality downstream is enhanced because pollutants are precipitated in the reservoir. Nevertheless, water flowing several Kilometers downstream showed similar quality to that of upstream. During seasonal changes, turnovers happen, so the quality of the water returned just like it was before constructing the dam! The water quality was estimated by diatoms inhabiting these waters. What about other communities? Rescue agriculture during drought periods Provide drinking water