Problematic SoilProblematic Soil

ContentsContentsDefinitionTypes (chemically)

AcidicSalineSodicAlkaline Causes Solution

Types (Physically)Fluffy paddy soilSandy soilHard pan soilWater logging and seeping References

problematic soilproblematic soil

The soil that causes additional problems

from the engineering point of view as a

result of the circumstances of its

composition or a change in environmental

conditions.

The soil having PH less than 7 is called acidic soil Extremely acidic soil has PH between 4-4.75 Causes of Acidic Soil? There are three basic things (PNK) that cause

acidic soil. The first, and most common, is simply that the organic matter and minerals that break down in a soil over time are acidic in nature, and make the soil acidic. This is common in pine forests and peat bogs.

Acid rain also becomes a cause of acid soil

Acid SoilAcid SoilSolutionAdding pulverized limestone or dolomite limestone (which has magnesium in addition to the calcium carbonate that makes up regular lime) is one of the fastest ways to increase your soil's pH. You'll generally want to look for something called "garden lime" or the above-mentioned "dolomite limestone" for your garden.

Acidic soilAcidic soil

Acidic Soil

The soil with excess salt (NaCl) is called saline soil

Salt Sources These salts originate from the natural weathering

of minerals or from fossil salt deposits left from ancient sea beds.

Saline soil problems It is caused by the accumulation of soluble salts in

the root zone. These excess salts reduce plant growth by altering water uptake and causing imbalances

Saline SoilSaline Soil Solution

There are two ways to manage saline soils:First, salts can be moved below the root zone by

applying more water than the plant needs. This method is called the leaching requirement method.

Second, salts can be moved away from the root zone to locations in the soil, other than below the root zone, where they are not harmful. 

Sodic soil

Soils with high levels of exchangeable sodium (Na) and low levels of total salts are called Sodic soilsCauses: Sodic soils may impact plant growth by: 1.) Specific toxicity to sodium sensitive plants2.) Nutrient deficiencies or imbalances 3.) High pH

Sodic SoilSodic Soil

SolutionThere are usually three options for

correcting soil-related problems: change the plant species to a more

tolerant specieschange the variety to a more tolerant

varietychange the soil.

Sodic SoilSodic Soil

Alkali soil

Alkali, or alkaline, soils are clay soils with high pH, a poor soil structure and a low infiltration capacity. Often they have a hard calcareous layer at 0.5 to 1 meter depth.Causes:The causes of soil alkalinity are natural or they can be man-made natural cause is the presence of soil minerals producing sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3) upon weathering no other source of man made sodium salts addition to the agriculture fields

AlkaliAlkali soilsoil

Solution: Alkaline soils with solid CaCO3 can be

reclaimed with grass cultures, organic compost, waste hair and feathers, organic garbage, etc. ensuring the incorporation of much acidifying material (inorganic or organic material) into the soil, and enhancing dissolved Ca in the field water by releasing CO2 gas. Deep plowing and incorporating the calcareous subsoil into the top soil also helps

They are characterised by low bulk density of the topsoil resulting in the sinking of farm animals and labourers as well as poor anchorage to paddy seedlings.

Such soils can be reclaimed by, passing of 400 kg stone roller.

Fluffy Paddy SoilFluffy Paddy Soil

The size of the particles are the largest. It is granular and consists of rock and mineral particles that are very small. The texture is coarse.. Sandy soil is composed of 60-70% sand, 20-25% silt and 10-15% clay.

Hard pan occurs in red soil areas below 15 cm depth due to the movement of clay and iron hydroxides and settling at shallow depth, preventing the root proliferation.

These soils can be reclaimed by Chiselling the soils with chisel plough at 0.5 m

interval first in one direction and then in the direction perpendicular to the previous one, once in three years.

Hard Pan SoilHard Pan Soil

The soils are weakly aggregated soil structure are easily The soils are weakly aggregated soil structure are easily

broken by the impact of rain drops resulting in the formation of broken by the impact of rain drops resulting in the formation of

clay crust at the soil surface. clay crust at the soil surface.

The clay pan prevent the emerging seedlings and arrest the The clay pan prevent the emerging seedlings and arrest the

free exchange of gasses between the soil and atmospherefree exchange of gasses between the soil and atmosphere

Surface crusted soilSurface crusted soil

soft clay soilsoft clay soilsoft clay soil Defined as saturated clay soils that

have low values of shear strength and coefficient of textures also have high values for compression and secondary compression and creep behavior.

collapsible soilcollapsible soil

A soil which is possible to bear high stress value low settlement. In case that soil exposed to high amount of moisture they quickly collapse and a high settlement occur.

Swelling soilSwelling soil

Swelling soil Is the soil that gives a significant increase in size when absorbed water as it gives high shrinkage ratio at the exit of the water. The swelling ratio depends on increasing dry density and increase the percentage of clay

DISPERSIVE SOILSDISPERSIVE SOILSDispersion can occur in any given soil with a high

percentage of exchangeable sodium percentage (ESP), causing internal erosion and eventually piping through embankment dams.

Water logging refers to the saturation of soil with water. Soil may be regarded as water logged when the water table of the groundwater is too high to conveniently permit an anticipated activity, like agriculture.

Water LoggingWater Logging

Causes Of Water LoggingCauses Of Water Logging

(3)-Impervious Obstruction.

(4)-Inadequate Drainage.

(5)-Impervious Soil (6)-Flat country

Slope

Water LoggingWater Logging

Prevention Of Water LoggingPrevention Of Water Logging

There are many following steps to control the water logging:Canal ClosuresLowering Full Supply LevelLining Of Canals and water coursesProvision Of Intercepting DrainsProvision Of Surface DrainsPumpingPlantationCrop Rotation

Seepage of waterSeepage of water

PumpingPumping