Solution Buddy

Answer the following question in brief:

(1) State the main benefits of catchment/watershed treatment.

Ans.
Catchment treatment helps in achieving the objectives of soil conservation (i.e. prevention) of soil erosion) and protected irrigation for plant growth.


(2) Where are bunds built and how are they built?

Ans.

i) It is built on the steep slopes of hills as well as plain fields.

ii) Field is prepared on the slopes of hills by digging some parts and filling half part like steps.Where the soil dept is sufficient and water is available, the slopes are converted to bunds.


3) Explain the significance of contour trench.

Ans.

i) Rain water runoff in the hilly regions and mountain tops is reduced.

ii) Normally per thousand running metres length and 0.30m depth, 180 cubic metre and 0.45 m depth, 270 cubic metre water is stored.

iii) Soil erosion is reduced.

iv) Fallow land on the hill slopes is brought under cultivation.


(4) What should be done to prevent check dams from collapsing?

Ans.
In order of effectively slow water velocity to reduce erosion and to protect the channel between dams in a larger system, spacing must be designed properly. Check dams should be spaced such that the toe of the upstream check dam is equal to the elevation of the downstream check dam's crest.


(5) Write in brief about the procedure of constructing earthen stream dam.

Ans.

The procedure of constructing earthen stream dam is:

i) Check dam is constructed at the right place in the stream and excess water is released at a controlled speed.

ii) Dams are constructed with catchment area between 10 to 40 hectares and 42 to 500 hectares.


(6) Explain the care to be taken while deepening the streams.

Ans.

i) Streams are not to be deepened if they are filled with sand storage or alluvial soil.

ii) Stream deepening is suitable in "Bajada" part of the topography. It helps introducing excess rainwater runoff.

iii) It helps in controlling soil erosion.


(7) Write two precautions to be taken for catchment / watershed treatment.

Ans.

i) To get ensured benefits of catchment treatment the type of soil, sloped of land , thickness of soil layers , other geographical conditions are to be studied systematically .

ii) Don't pour toxic household chemicals down the drain , take them to hazardous waste centres.

iii) Use hardy plants that require little watering, fertilizers or pesticides in your yard .