Give the disadvantages of constructing big dams across the river. How does construction of dams across the river get linked with production of greenhouse gases?
Disadvantages of constructing of big dams across the river are:
(a) A vast variety of flora and fauna (plants and animals), large areas of agricultural lands and human settlements get submerged in the water of reservoir formed by the dam.
(b) The construction of dams disturbs the ecological balance in downstream area of ricer by decreasing the fertility of soil in the downstream area. This leads in decrease in crop yields.
(c) The fish in downstream area don’t get sufficient nutrients and fish production also decreases.
(d) Production of greenhouse gasses: The vegetation which is submerged under water at the dam rots under anaerobic condition and produces large amount of methane, which is a greenhouse gas.