What are the primary benefits of lining irrigation channels________________?
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Answer: B. decreases the waterlogging area
Explanation
Impervious canal linings prevent massive seepage losses from infiltrating surrounding agricultural subsoils. Eliminating continuous seepage stops groundwater tables from rising toward the surface root zone. Lowering regional water table elevations successfully decreases the total land area affected by waterlogging. Waterlogging occurs when excessive irrigation seepage raises shallow water tables into crop root zones. Lining materials include concrete, asphalt, plastic membranes, and compacted clay blanket installations. Unlined canals typically lose substantial percentages of diverted water through porous earthen perimeters.
Irrigation modernization projects prioritize canal lining to conserve water and prevent soil salinization. Decreasing waterlogged areas restores agricultural productivity across low lying command region lands. Water conservation from canal lining increases available supplies for tail end farming communities. Option A increases the waterlogging area contradicts the fundamental purpose of canal lining technologies. Option C does not change ignores the proven hydrological impact of sealing conveyance channel seepage. Option D is incorrect because option B correctly identifies the reduction in waterlogged land.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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