2. Page no 1 Water logging?
Page no 4 When and why it
cause
Page no 5 Water logging and
salinity
Page no 6 Water logging in
Pakistan
3. Page no 7 Affected areas of
Pakistan
Page no 12 Impact on
agriculture
Page no 14 Impact on land
Page no 18 Control on water
logging
4. WATER LOGGING
Water logging is presents the situation
whereby the underground water comes
on the surface of land and in certain
cases it gathers on the ground level of
lands it may assume the shape of
streams
5. When and why it cause?
Waterlogging may be a natural condition of
the soil, but can worsen with deterioration in
soil structure
It occurs when rainfall exceeds the ability of
some soils to drain surplus water away
It is often perceived that waterlogging is a
surface water problem that surface drains
will overcome. However, in many situations
waterlogging is due to the soil profile (soil
below the ground surface) being saturated
and some type of subsurface drainage may
be necessary to overcome this problem
Unfortunately, some soils and areas, due to
their location, cannot be economically or
feasibly drained by any means
Susceptibility maps indicate that
waterlogging is high to very high over more
than 50% of the Corangamite region and is:
o usually a seasonal problem
o caused by a relatively impermeable
layer through which water moves only
very slowly
6. o due to soil compaction, sodic soils, high
rainfall
Water logging and salinity
As a result, the lands become
uncultivated. In same case underground
water does not reached the upper
surface it remains slightly low on land so
different salts accumulated near the
roots of plants this situation is called
salinity. So water is not sufficient water
available for plant growth (irrigation).
These salts are not absorbed in land.
These salt is gather in the form of layers
on land, they leads decrease in the
productivity of land and finely it become
uncultivated
7. Water logging in Pakistan
38% of Pakistan irrigated land was
damaged by water logged
14% saline
Only 45% are cultivated at present
time
Accumulation on Indus basin
8. Affected areas of Pakistan
Water logging mainly affect
agricultural sector it is estimated
that 50% land was affected by water
logging in Pakistan
While 30 lace of acres became
uncultivated
In case of Punjab 70,000 acres of land
affected by water logging every year
10. Impact of water logging on
agriculture
Effect of water logging on framer
Waterlogging is currently a significant land
degradation threat across much of south-
west Victoria
Vast areas including the Heytesbury Soldier
Settlement and the Victorian Volcanic Plains
represent landscapes significantly affected
by waterlogging
Is a significant problem for dairy farmers
during winter and early spring where soils
can remain waterlogged for considerable
periods
Causes poorer pastures, both in growth and
quality
Water logging and Stalinization are major
impediment to the sustainability of irrigated
11. lands and livelihoods of the farmers, especially
the smallholders, in the affected areas of the
Indus Basin. These problems are the result of a
multitude of factors, including seepage from
unlined earthen canals system, inadequate
provision of surface and subsurface drainage,
poor water management practices, insufficient
water supplies and use of poor quality
groundwater for irrigation. About 6.3 million ha
are affected by different levels and types of
salinity, out of which nearly half are under
irrigated agriculture. Since the early 1960s,
several efforts have been made to improve the
management of salt-affected and waterlogged
12. soils. These include lowering groundwater
levels through deep tu
bewells, leaching of salts by excess irrigation,
application of chemical amendments (e.g.
gypsum, acids, organic matter), and the use of
biological and physical methods. However, in
spite of huge investments, the results have in
general been disappointing and the problems of
13. water logging and salinity persist. Water
logging force farmer to sell him land.
Effect on plants
Waterlogging occurs when there is too much
water in the plant’s root zone, which results in
the roots not being able to access enough
oxygen for respiration. Waterlogging, when it
occurs, is a major constraint to production.
Plant growth is affected, and under certain
conditions will even lead to premature plant
death
Seeding rates
Increase sowing rates in areas susceptible to
waterlogging to give some insurance against
uneven germination, and to reduce the
dependence of cereal crops on tillering to
produce grain. Waterlogging depresses tillering.
High sowing rates will also increase the
competitiveness of the crop against weeds,
which take advantage of stressed crops
14. . Waterlogged seedlings can die before
emergence or show symptoms similar to
nitrogen deficiency.
Lower leaves turn purple-red to yellow, then
die.
Prolonged waterlogging causes root death and
eventually death of the whole plant. Plants are
more susceptible to root disease.
Waterlogging of adult plants causes yellowing
of lower leaves.
Salinity magnifies waterlogging effects, with
more marked stunting and oldest leaf marginal
necrosis and death
Signs of waterlogging include:
yellowing of crops and pastures;
the presence of weeds such as toad rush,
copula, dock and Yorkshire n fog grass;
dark, wet, slimy, usually with algae on the
topsoil
grey or greenish colored subsoil (permanent
waterlogging creating reducing conditions);
15. The presence of orange mottles in soil
profiles (although some mottles may
have been caused by waterlogging in previous
climates).
Effect of water logging on land
Areas affected by water logging
Germination and early growth can be much
worse on saline areas after waterlogging
events
Water accumulating or poorly drained areas
such as valleys, at the change of slope or
below rocks Duplex soils, particularly sandy
duplexes with less than 30 cm sand over
clay
Low nitrogen status crops
In very warm conditions when oxygen is
more rapidly depleted in the soil
Deeper sown crops
16. Figure 1 Hole in the ground filling with water
observe where soils are boggy and crops are
yellow;
mark out the areas that are affected, either
with posts laid on the ground or on an
accurate map;
17. at harvest time observe where the crops are
poor and check this against earlier
observations;
survey seepage interceptor drains, placing
them immediately above affected sites or
consider raised beds;
install drains when the soils are moist (for
example, after summer or autumn rains);
Effects of water logging
18. Cause of water looging
Control of water logging
Biological control
Water logging is contrl by planting trees bushes
plants on water table and control water logging
Drainage
19. Proper drainage system also help to control water
logging and choice of crop,seedling ,fertilization and
weed control aslo control the water logging
Best way to control water logging
Remove excess water (drainage options)
o Surface drainage – start with the
perimeter
o Subsurface drainage
o Raised beds (cropping areas) - to
reduce soil compaction and improve soil
structure
Minimize compaction (non-drainage
options)
o Controlled traffic flat beds (cropping
areas) - to reduce soil compaction and
improve soil structure
o Stock management - graze and spell
(rotation) based on understanding of
plant and soil needs
o Land class fencing
o
20. Improve water storage in profile
Removal of excess water through drainage
options
Surface and sub-surface drainage is
commonly used to rehabilitate waterlogged
land and improve soil structure
Currently, over 80% of dairy land has some
form of surface drainage and up to 20% has
sub-surface drainage (MacEwan 1998)
- Surface drains
- Subsurface drains
Surface drainage - Is very useful in
removing excess water from land in a
controlled manner and as quickly as
possible, to an artificial drainage system or
a natural watercourse. This should be done
with no damage to the environment.
Types of surface drainage include:
21. Ditches or open
drains:
o These vary in size and length and can
be formed by spinner cuts or excavators
o Must be very wary of constructing open
drains in dispersive soil as they are
highly prone to erosion
Grassed Waterways:
22. o These are usually shallow, varying in
width from narrow to meters wide, but
are constructed such that they are often
grazed as part of the paddock
o They are sometimes used to bring drain
outflows down slopes to prevent erosion
without considerable expense
Humps and hollows (bedding):
o Hump and hollowing is the practice of
forming (usually while renovating
pastures) the ground surface into
parallel convex (humps) surfaces
separated by hollows. The humped
shape sheds excess moisture relatively
quickly while the hollows act as shallow
surface drains
o Humps and hollows are useful in areas
or on soil types that are not suitable for
tile or mole drainage
o
