Soil and water conservation techniques

1. Hydrology and Watershed Management
(SAF-3108)
Topic- Soil and Water Conservation;
Water Harvesting Techniques
SUBMITTED BY:
Ameed Shafi (BSF-2020-602)
Amreen Mushtaq(BSF-2020-593)
Danish Najar(BSF-2020-605)
Khan Amrun(BSF-2020-587)
Musaib Alum (BSF-2020-595)
Rahat(BSF-2020-589)

2. Soil and water conservation?
There are always strong links between measures for soil
conservation and measures for water conservation.many
measures are directed primarily to one or the other but most
contain an element of both. Reduction of surface run off by
structures or by changes in land management will also help to
reduce erosion similarly reducing erosion will increase infiltration
and thus help in water conservation.

3. Purpose of Soil And Water
Conservation Measures
•To control runoff and thus prevent loss of soil by soil
erosion;
•To reduce soil compaction;
•To maintain or to improve soil fertility;
•To conserve or drain water;
•To harvest water.

4. Classification of Soil and Water
Conservation Measures
 physical measures (also termed mechanical or
technical measures);
 biological measures (also termed vegetative
measures);
agronomic measures (sometimes called best
management practices)

5. Physical Soil and Water
Conservation Measures
Physical measures are structures built for soil and water
conservation. Some principles should be considered. They should
aim to
increase the time of concentration of runoff, thereby allowing
more of it to infiltrate into the soil;
divide a long slope into several short ones and thereby reducing
amount and velocity of surface runoff;
reduce the velocity of the surface runoff;
protect against damage due to excessive runoff
In most systems any physical measure can be built like check
dams or contour ditches.

6. Structures built for soil and water conservation
Stone/Earth terraces Stone/Earth Bund Check Dam
Dams Retention Reserver Planting
pits

7. Biological measures
Biological measures for soil and water conservation work by their
protective impact on the vegetation cover. A dense vegetation cover
prevents splash erosion;
reduces the velocity of surface runoff;
facilitates accumulation of soil particles;
increases surface roughness which reduces runoff and increases
infiltration;
the roots and organic matter stabilise the soil aggregates and increase
infiltration
These effects entail a low soil erosion rate compared with an uncovered
soil which shows in general a high soil erosion rate.
Other positive impacts have been observed, such as improved soil
moisture condition (or protection against erosion by wind).

8. Reforestation
In highly degraded areas reforestation is an important measure
for regeneration of the soil and water balances. Trees fulfil many
functions such as protection from erosion or conserving soil
moisture. Two decisions have to be made initially when
reforestation is to be done:
should the area be completely closed for cultivation and pasture
for a specific period? If so, the border must be marked clearly.
which works better: direct seeding or planting of nursery-grown
seedlings?
The answer depends on many factors such as climate, biotic
factors, soil, etc.

9. Agronomic Soil and Water
Conservation Measures
Agronomic conservation measures function by
reducing the impact of raindrops through interception and thus
reducing soil erosion and
increasing infiltration rates and thereby reducing surface runoff
and soil erosion
Some possible agronomic measures are
Strip croppping
Mixed cropping
Intercropping
Fallowing
Contour ploughing
Mulching
Agroforestry

10. Water Harvesting
The collection and sorting of water on the
surface of the soil for subsequent use is known
as water harvesting.

11. Methods of water harvesting
Runoff inducements- It is a method to induce,collect,store and
conserve local surface run off for agriculture in arid and semi arid
regions.It is done by constructing structures such as contour
bunds etc.
Land alteration- it is often the simplest and least expensive
method of water harvesting when It involves nothing more than
building walls or ditches to collect run off from existing or man
made catchments such as rock outcrops or roads.
Chemical treatments-In many insidences harvested water is not
suitable for drinking purpose or etc without prior treatment.in such
cases various procedures and methods are used for disinfection
and treatment of harvested water such as chlorination, heat
treatment,implimantion of filter systems.

12. .
Runoff farming- It is basically a use of water harvesting to grow
a crop.In this technique instead of runoff being left to cause
erosion it is harvested and utilized in farming.
Water spreading- In this technique the flood water is spread on
the terraces where some amount of it is absorbed by the soil
which is used later on by the crops grown in the area.
Micro-catchments- Microcatchments are mainly used for
growing trees or bushes. This technique is appropriate for small-
scale tree planting in any area which has a moisture deficit.
Besides harvesting water for the trees, it simultaneously
conserves soil.
Dug wells-A dug well recharge augments the groundwater to
ensure long term sustainability. Dug wells are one of the major
sources of drinking water in rural India.

13. .
Tanks-Rainwater tanks are devices for collecting and
maintaining harvested rain.
Farm ponds-The farm ponds are constructed at the lower side
of the fields. The runoff from the contributing fields is chanalized
into the pond. In light soil, the dugout ponds are lined to improve
the storage efficiency by containing the seepage.
Percolation tanks-Percolation tank is an artificially created
surface water body, submerging in its reservoir a highly
permeable land so that surface runoff is made to percolate and
recharge the ground water storage.
Inter row water harvesting- In this system a portion of the main
field is cultivated & remaining area is used for harvesting excess
of water (runoff). Usually the uncultivated area is managed or
treated in such a way that runoff would be induced. In many
situations surface modification may be required to get runoff

14. .
Broad bed furrows-In a broadbed-and-furrow
system, runoff water is diverted into field furrows (30
cm wide and 30 cm deep). The field furrows are
blocked at the lower end. When one furrow is full, the
water backs up into the head furrow and flows into
the next field furrow.

15. THANK YOU
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