It is important to make small check dams across the flooded gullies because they:
(i) hold water for irrigation
(ii) hold water and prevent soil erosion
(iii) recharge groundwater
(iv) hold water permanently
Small check dams hold water and prevent soil erosion, they help in recharging groundwater. So they are build across flooded gullies.
The pH of water sample collected from a river was found to be acidic in the range of 3.5 — 4.5, on the banks of the river were several factories that were discharging effluents into the river. The effluents of which one of the following factories is the most likely cause for lowering the pH of river water?
Among the statements given below select the ones that correctly describe the concept of sustainable development:
(i) planned growth with minimum damage to the environment.
(ii) growth irrespective of the extent of damage caused to the environment.
(iii) stopping all development work to conserve the environment.
(iv) growth that is acceptable to all the stakeholders.