Soil Erosion and Conservation Questions and Answers

Answer: B

The primary objective is to manage land and water resources holistically to improve productivity and livelihoods.

A watershed is the area that drains to a common point. Watershed development treats it as one unit, from ridge to valley: soil and water conservation works, water harvesting, afforestation, pasture and improved cropping are planned together so that rain is conserved, erosion is checked and the people living there gain stable incomes.

The other options run against the idea. The programmes do not aim to convert land to urban or industrial use, and they promote diversified land use, including crops, trees and livestock, rather than a single-crop monoculture.

Answer: B

Bench terracing suits areas having high rainfall, steep slopes.

Bench terraces convert a steep hillside into a series of level or nearly level steps separated by risers. They cut the slope length, slow runoff and let rain soak in, which makes cultivation possible on slopes of roughly 16 to 33 percent in high-rainfall hill regions such as the north-east, where shifting cultivation would otherwise cause severe erosion.

Flat lands and sandy plains do not need terracing, because they have little slope for water to gather speed. Waterlogged areas need drainage, not structures that hold water back.

Answer: D

A mini watershed is 1-100 ha in size.

The size classification used in Indian soil and water conservation texts runs from the largest to the smallest unit:

So the other three options are the ranges of the macro, sub- and milli watersheds. The mini watershed, the smallest unit, is the scale at which farm-level treatments are usually planned.