Soil geography notes.pdf

15,134 views 30 slides Jun 21, 2022
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About This Presentation

Notes for soil geography M A Ranchi university


Slide Content

Unit 1:
Soil geography
• Rocks are the pages of history of the Earth. As we study the evolution and
development of rocks we come to know the history of the Earth. Every
soil type is the product of physical, chemical and biological weathering of
various rocks.
• Soils are the medium by which human being can produce the food and
sustain his life. Human beings are using the soils from the invention of
agriculture systems. There are many evidences to prove the use of soils
by human being.
• Study of soils include in Soil sciences. The study of Soil Geography is the
part of Geography. There are two main branches of Geography. These are
Physical Geography and Human Geography.
• Physical Geography studies the Physical features and phenomena of the
earth, while Human Geography studies the various aspects of human life.
Thus, the interdisciplinary nature of Geography arose various sub
branches of Geography. Soil Geography is the branch of Physical
Geography.
• Physical Geography is the main branch of Geography which deals with the
study of land features, climate, oceans, plants, animals and rocks. Soils
are the product of rocks. Soil Geography is the science which deals with
the study of characteristics and types of soils. Advance techniques and
research have vital role in the development of Soil Geography.
• There are two types of Soil Geography:
• 1. General Soil Geography: It studies the factors that influence the
formation of soil and the general laws of geographic distribution of soils.
• 2. Regional Soil Geography: It studies the regionalization and description
of soils in individual region.
• Soil Geography compiles the comparative geographic method to study
the distribution of soils with relation to factors affecting on soil
formation.
Definition
• Soil Geography is an interdisciplinary science. The nature and scope of
this branch is vital. So it is very complex to define the Soil Geography.

• Study of characteristics of soil and their distribution with geographic
perspective is called Soil Geography.
• A branch of soil sciences that studies pattern of distribution of soil on the
surface of the earth.
• V. V. Dokuchaev- It is the branch of Soil science, which deals with physical
and biological properties of soil
Nature (Story read)
• As it is a branch of Physical Geography and as it is a science, the nature of
soil geography is dynamic.
• Soil Geography was descprtive subject in the period of 18th century.
• In the late 19th century it gets its position and separate identity as a
branch of knowledge. Various crops, distribution of crops, types of crops,
yield and quality of production enhances the study of soil geography. A
change in environment and agriculture brings the changes in the study of
soil geography.
• Descprtive nature of Soil Geography changed and become analytical and
scientific. According to V. V. Dokuchaev, in soil geography, location of
soils, their characteristics, nature and patterns are checked and studied.
Soil geography studies problems of soil, their scope, need and seriousness
of their quality.
• Modern geography is become so powerful and scientific. Researcher of
soil geographer also studies crop yielding decision, area for specific crop,
its economics, etc. Soil Geography relate with many branches.
Geomorphology, Climatology, Bio-Geography, ZooGeography, Chemistry,
Agriculture and Economics are related to Soil Geography. In the research
of Soil Geography researcher need to study of Statistics and Computer
science.
• Soil Geography In the explanation of nature of Soil Geography V. V.
Dokuchaev explained that it is the study of soil in various regions. It also
studies formation, characteristics and changes in the soils. Changes in
physical, chemical and biological characteristics of soils are occurred due
to which causes are also studied in this branch. So the nature of this
branch is completely dynamic.
Scope (Story read)

• Scope of the Soil Geography is vast. In the period of development of Soil
Geography its scope is only limited to distribution, type and
characteristics of soils. But, after 19th century scope of soil geography has
been increased. Productions of crops become a crucial issue nowadays.
Farmers are facing the problem of decreasing yields, various crop
diseases, soil degradation and soil salinity.
• In earlier days there was a limited scope to soil Geography. But in the
modern period of science and technology scope of soil Geography has
been widen. Biologists, environmentalists and geographers are widely
collecting the information of soil. Research has been carried out in the
field of soil science. Every nation is engaged in agriculture, so it is the
requirement of every nation to get information and knowledge of soil. By
using statistical techniques measurement of agricultural efficiency, cost
benefit ratio means input-output ratio, nutrition, malnutrition,
starvation, hunger, health, food security these problems can be solved.
Population of various countries, availability of food to sustain that
population is comparatively studied by geographers.
• In the 20th century, arable land, conservation of land becomes essential.
Irrigation, use of fertilizers, use of technology, changing pattern of crops,
pollution affects on agriculture. Due to regional imbalance it is very
important to increase the agricultural production. Organic farming,
sustainable farming and use of biotechnology increased the facets of soil
geography. Soil Geography has challenges of soil pollution, soil
degradation, soil contamination and soil conservation. Soil fertility, soil
salinity (saltation), water logging, residues in crops and fruits, nutrient
losses, diseases on crops erosion and soil loss are some of the burning
issues. Soil is eroded by natural and artificial causes. Floods, stormy
winds, cyclones are the natural causes while deforestation, over use of
water, use of pesticides, insecticides and fertilizers are artificial causes.
Soil is the only medium by which human being can meet the need of food
for increasing population. So it is an integral part of the study for human
being.
• Various institutes engaged in the study of soil and related problems.
World Soil Information (WIS) and his partners involved in various
externally funded and co-funded projects. The aim of this institute is to
collect, analyse, dissemination of quality assessed soil information.

• The Indian Institute of Soil Science at Bhopal in Madhya Pradesh is an
ideal institute in India. The awareness and information of soil increasing
day by day. Farmers, scientists, biologists and environmentalists are now
engaged the spreading of knowledge of soil. It is become an essential to
become a soil friendly nowadays. So the world soil information society
has decided to celebrate the World Soil Day on 5th December per year.
But more than this it is important to become aware of problems related
to soil. New surveys and techniques will bring detailed information of
worldwide soil. So it is important to find out precise formula of universal
soil loss and it is only possible when government and research institute
will take initiatives for the establishment of soil testing labs and
infrastructure.
Significance of soil geography (Just add study off)
1. Medium for plant growth.
• Soil is where most plants grow. Soil provides anchorage for the plants as
well as protection of roots from damage.
• It is where or a medium through which water, air and nutrients are made
available to plants.
• The well-aerated soil facilitates the absorption of water and nutrients
from the soil by plants.
2. Soil support animal life.
• As soil support plant life it also support animal life because plants are the
source of foods to animals and this is most for herbivores.
• Also some animals eat soil as food in form of salt licks for example
pregnant women who lack some minerals in their bodies.
3. Soil provide habitat for living organisms
• In the soil there are some animals living there example burrowing animals
like rodents, earthworms and termites
4. Provide sites for agricultural activities
• The fertile soil promotes agriculture activities, both animal husbandry
and crop cultivation.
• This is because soil supports the growth of pasture for animals.

5. Provide settlement

• Soil influences distribution of settlement for example the areas with good
fertile soil are densely populated compared to the areas with poor soil.
6. Soil provide building materials
• Soil is used in making bricks, tiles and white wash. All these materials are
used in building houses, bridges etc.
• Also soil is used directly in road construction
7. Source of minerals
• There are some minerals found in soil that can be extracted for
commercial purposes.
• Also it is used to manufacture fertilisers as it contain minerals for example
the fertilisers that contain phosphate e.g. In Minjingu (Manyara) region.
8. It provides raw materials for pottery and ceramics
• Soil is used in making pots and these help to provide income to those who
engage in this activity.
Its relation with pedology
SOIL SCIENCE:- It is the study of soil as a natural resource on earth surface. It
not only studies the physical, chemical and biological properties of soil, but also
their utility, management and impact on living organisms. It, therefore, is
further divided into two branches, namely- Pedology and Edaphology.
1. PEDOLOGY
. Study of soil in its natural setting.
a. Studies chemical and physical properties of soil.
b. Deals with- soil genesis, chemistry, morphology, soil classification
and soil mapping.
c. Example- Advising a farmer on what type of crop would grow best
on his soil would require the pedological study of that soil.
2. EDAPHOLOGY (extra)
. Study of soil in reference to soil-dependent uses.
a. Studies the influence of soil on organisms (especially plants).
b. Deals with- ecological relationship of soil with agricultural practices
and plants, conservation of soils, composition of soil (mineral
matter, organic matter, soil water, porosity and soil air etc), volume
and depth of soil; processes affecting soil, such as- leaching etc.

c. Example- Edaphologist advises a farmer on what kind of measures
he should adapt to overcome the changes in soil due to climate
change or drought.
3. SOIL GEOGRAPHY
. Study of distribution of soil types on earth surface.
a. Since soil is a product of physical environment that varies in time
and space, soil also varies with time and space.
b. Deals with- factors that influence soil formation, types of soil
structures, soil zones, geographic distribution of soils.
c. Example- Soil maps showing different kinds of soils in India, such as-
alluvial soil, regur soil, red soil, sandy soil etc
Soil Forming factors
Soil forms layers or horizons, roughly parallel to the earth’s surface, in
response to five soil forming factors. The whole soil, from the surface to its
lowest depths, develops naturally as a result of these five factors. The five
factors are: 1) parent material, 2) relief or topography, 3) organisms
(including humans), 4) climate, and 5) time. If a single parent material is
exposed to different climates then a different soil individual will form. If any
one of the five factors is changed but the remaining four factors remain the
same, a new soil will form. This process is called “soil genesis”.
1. Parent Material
• Few soils weather directly from the underlying rocks. These residual soils
have the same general chemistry as the original rocks.
• More commonly, soils form in materials that have moved in from
elsewhere. Materials may have moved many miles or only a few feet.
• Windblown loess is common in the Midwest. It buries glacial till in many
areas. Glacial till is material ground up and moved by a glacier.
• The material in which soils form is called “parent material.”
• In the lower part of the soils, these materials may be relatively
unchanged from when they were deposited by moving water, ice, or wind
2. Organisms
• Plants, animals, microorganisms, and humans affect soil formation.
Animals and microorganisms mix soils and form burrows and pores.

• Plant roots open channels in the soils. Different types of roots have
different effects on soils. Grass roots are fibrous near the soil surface and
easily decompose, adding organic matter.
• Taproots open pathways through deeper layers. Microorganisms affect
chemical exchanges between roots and soil.
• Humans can mix the soil so extensively that the soil material is again
considered parent material.
3. Climate
• Soils vary, depending on the climate. Temperature and moisture
amounts cause different patterns of weathering and leaching.
• Wind redistributes sand and other particles, especially in arid regions.
• The amount, intensity, timing, and kind of precipitation influence soil
formation.
• Seasonal and daily changes in temperature affect moisture
effectiveness, biological activity, rates of chemical reactions, and kinds
of vegetation.
4. Topography
• Slope and aspect affect the moisture and temperature of soil.
• Steep slopes facing the sun are warmer. Steep soils may be eroded and
lose their topsoil as they form.
• Thus, they may be thinner than the more nearly level soils that receive
deposits from areas upslope. Deeper, darker colored soils may be
expected on the bottom land.
5. Time (Spatio temporal dimension (data collected in a particular time))
• Time is also a component for the other factors to interact with the soil.
Over time, soils exhibit features that reflect the other forming factors.
• Soil formation processes are continuous. Recently deposited material,
such as the deposition from a flood, exhibits no features from soil
development activities.
• The previous soil surface and underlying horizons become buried. The
time clock resets for these soils. Terraces above the active floodplain,
while similar to the floodplain, are older land surfaces and exhibit
more development features.
Process of soil formation
Intro- Soil is formed by the process of weathering during which rocks break
down to form soil particles. This breaking down of rock occurs over a period of

millions of years. Weathering can be physical, chemical, and biological. The
bedrock breaks down into pieces due to the effects of heat, cold, water, wind,
and rain. Microbes, insects, and rodents also help in this process. The roots of
trees also help in the process of weathering.
Process (explain in own words)
(i) Addition of mineral and organic matter to the soil.
(ii) Losses of mineral and organic matter from soil.
(iii) Translocation of mineral and organic matter from one point of soil profile
and deposited at another horizon.
(iv) Transformation of mineral and organic matter in the soil and formation of
definite layers.
Soil development (explain in own words)
Soil develops through a process involving weathering, fracturing and
comminution of rock into mineral soil particles. These processes evolve at
varying speeds, depending on the intensity of the factors that are brought to
bear.
Five stages of development of tropical soil as follows: (Mohar and Van Baren
(1959) way)
(i) Initial stage – Unweathered parent material.
(ii) Juvenile stage – Weathering just started, but much of the original material is
still unweathered.
(iii) Verile stage – Easily weatherable minerals have been decomposed for the
greater part, the clay content has increased and a certain mellowness is
discernible. The content of soil components less susceptible to weathering is
still appreciable.
(iv) Senile stage – Decomposition arrives at a final stage and only the most
resistant minerals have survived.
(v) Final stage – Soil development has been completed and the parent material
is fully weathered.
Physical process

• The main soil physical processes influencing soil formation are movement
of water plus dissolved substances (solutes) and suspended particles,
temperature gradients and fluctuations, and shrinkage and swelling.
• (Other answer) This is the disintegration of rocks into smaller particles
with no alteration in their molecular structure. Air and water are agents
of physical weathering. Windblown on rocks, heavy downpour of rain,
water waves from the sea can facilitate a gradual fragmentation of rock
particles to sediments which eventually become soil.
Biotic and abiotic process
• Biotic factors includes biological i.e. living factors like plants, animals.
When plants grow their roots penetrate deep inside the ground and
result in breaking of soil particles and formation of soil.
• Abiotic factors means physical factors such as temperature, wind and
water. When water flow with high speed it results in breaking of rocks.
Wind also result in weathering when blow with high speed. The
difference in the temperature of the day and night time results in
expansion and contraction of the rocks leading to weathering and
formation of soil.
• (Other answer) In this process biological organisms facilitate rock
fragmentation. Tree roots and mosses grow or penetrate through rocks
and create pore spaces which gradually pull rocks apart. Animals burrow
through rocks and create disintegration. Micro organisms like lichen (a
symbiotic relationship between fungi and algae) release chemicals which
break down rock minerals.
Chemical process
In chemical weathering chemical reactions within rocks create changes in their
mineral composition. Examples of chemical reactions leading to weathering are
hydrolysis, carbonation, oxidation and hydration.
• Hydrolysis: hydrolysis occurs as rain water seeps through rocks and the
hydrogen ion (H+) in water reacts with metallic ions in rocks resulting in
dissolution of rock minerals.
• Carbonation: During carbonation carbon dioxide from the air and from
living organisms dissolve in water to form carbonic acid. This acidifies
water in rocks leading to further chemical reaction with rock minerals.

• Oxidation: in oxidation oxygen from the air reacts with iron in rocks to
form iron oxides. This reaction creates a rusty brown colouration on
rocks.
Soil Profile
• (First option)A soil profile is a vertical section of soil like the diagram above. It
allows you to examine the structure of soil. A soil profile is divided into layers
called horizons. The main soil horizons are A, B, C and D.
• Most important for plant growth, the A and B horizons are the top two layers of the
soil. The A horizon is where there is most soil life and is sometimes called
topsoil. Depending on the soil, the A horizon can be further divided into A1, A2 or
Ao (organic). The B horizon is where clays and materials washed down from the A
horizon accumulate. This is sometimes called subsoil.
• The C Horizon consists of weathering rock.
• The D horizon is bedrock. This is rock which has weathered to produce the soil you
see above it (unless the soil has been deposited from elsewhere eg floodplains contain
soil that has been carried downstream in water and then deposited as the flood
recedes).

Second option The soil is the topmost layer of the earth’s crust mainly
composed of organic minerals and rock particles that support life. A soil profile
is a vertical cross-section of the soil, made of layers running parallel to the
surface. These layers are known as soil horizons.

The soil is arranged in layers or horizons during its formation. These layers or
horizons are known as the soil profile. It is the vertical section of the soil that is
exposed by a soil pit. The layers of soil can easily be identified by the soil colour
and size of soil particles. The different layers of soil are:
• Topsoil
• Subsoil
• Parent rock
Each layer of soil has distinct characteristics.
Soil profile helps in determining the role of the soil as well. It helps one to
differentiate the given sample of soil from other soil samples based on factors like
its colour, texture, structure, and thickness, as well as its chemical composition.
1. The O-Horizon
• The O horizon is the upper layer of the topsoil which is mainly composed
of organic materials such as dried leaves, grasses, dead leaves, small
rocks, twigs, surface organisms, fallen trees, and other decomposed
organic matter. This horizon of soil is often black brown or dark brown in
colour and this is mainly because of the presence of organic content.
2. The A-Horizon or Topsoil
• This layer is rich in organic material and is known as the humus layer. This
layer consists of both organic matter and other decomposed materials.
The topsoil is soft and porous to hold enough air and water.

• In this layer, the seed germination takes place and new roots are
produced which grows into a new plant. This layer consists of
microorganisms such as earthworms, fungi, bacteria, etc.
3. The E-Horizon
• This layer is composed of nutrients leached from the O and A horizons.
This layer is more common in forested areas and has lower clay content.
4. The B-Horizon or Subsoil
• It is the subsurface horizon, present just below the topsoil and above the
bedrock. It is comparatively harder and more compact than topsoil. It
contains less humus, soluble minerals, and organic matter. It is a site of
deposition of certain minerals and metal salts such as iron oxide.
• This layer holds more water than the topsoil and is lighter brown due to
the presence of clay soil. The soil of horizon-A and horizon-B is often
mixed while ploughing the fields.
5. The C-Horizon or Saprolite
• This layer is devoid of any organic matter and is made up of broken
bedrock. This layer is also known as saprolite. The geological material
present in this zone is cemented.
6. The R-Horizon
• It is a compacted and cemented layer. Different types of rocks such as
granite, basalt and limestone are found here.

Unit 2:
Soil Organisms
• Soil organism, any organism inhabiting the soil during part or all of its life.
Soil organisms, which range in size from microscopic cells that digest
decaying organic material to small mammals that live primarily on other
soil organisms, play an important role in maintaining fertility, structure,
drainage, and aeration of soil.
• They also break down plant and animal tissues, releasing stored nutrients
and converting them into forms usable by plants.
• Some soil organisms are pests. Among the soil organisms that are pests of
crops are nematodes, slugs and snails, symphylids, beetle larvae, fly
larvae, caterpillars, and root aphids.
• Some soil organisms cause rots, some release substances that inhibit
plant growth, and others are hosts for organisms that cause animal
diseases.
Macro Animals
• Macrofauna, in soil science, animals that are one centimetre or more long
but smaller than an earthworm. Potworms, myriapods, centipedes,
millipedes, slugs, snails, fly larvae, beetles, beetle larvae, and spiders are
typical members of the macrofauna.
• Many of these animals burrow in the soil, aiding soil drainage and
aeration; in addition, some organic material passes into the soil through
the burrows.
• Most macrofauna consume decaying plant material and organic debris,
but centipedes, some insects, and spiders prey on other soil animals.
1. Earthworms
• Earthworms pass organic matter through their bodies, grinding it
with the help of tiny stones in their gizzard.
• The material passes out of the worm's body in the form of worm
castings, which are the richest and finest quality of all humus
material.
• Fresh castings are markedly higher in bacteria, organic material, and
available nitrogen, calcium, magnesium, phosphorus, and potassium
than soil itself.
2. Sowbugs

• Sow bugs and pillbugs (Isopods) are small, fat-bodied, flat decomposers
that closely resemble each other.
• The way to tell them apart is by the fact that only pillbugs are able to roll
up into a ball.
• Like other crustaceans, sowbugs breath through gills and require a moist
environment. They feed on rotting woody materials and highly durable
leaf tissues.
3. Mites
• Fermentation mites, also called mold mites, are transparentbodied
creatures that feed primarily on yeasts in fermenting masses or organic
debris.
• Literally thousands of these mites can develop into a seething mass over
a fermenting surface.
• Because of this, they often become pest species in fermenting industries
such as wineries and cheese factories. They are not pests in the compost
pile.
4. Centipides
• Centipedes are found frequently in soil micro-communities. They prey on
almost any type of soil organism that is within their size range or slightly
larger.
• Centipedes have a flattened body, and their legs are much longer than
those of a millipede (thousand-legged). They are also much larger and
faster moving.
5. Rodents
• Relatively small gnawing mammals (such as a mouse, squirrel, or beaver)
that have in both jaws a single pair of incisors with a chisel-shaped edge.
6. Insects
• Insects (from Latin insectum) are pancrustacean hexapod invertebrates of
the class Insecta. They are the largest group within the arthropod phylum.
• Insects have a chitinous exoskeleton, a three-part body (head, thorax and
abdomen), three pairs of jointed legs, compound eyes and one pair of
antennae.
Micro Animals and Plants
Relation: Herbivory is an interaction in which a plant or portions of the plant
are consumed by an animal. At the microscopic scale, herbivory includes the

bacteria and fungi that cause disease as they feed on plant tissue. Microbes
that break down dead plant tissue are also specialized herbivores.
1. Nematodes
• Nematode parasites of animals occur in almost all organs of the body,
but the most common sites are in the alimentary, circulatory, and
respiratory systems.
• Some of these worms are known by such common names as hookworm,
lungworm, pinworm, threadworm, whipworm, and eelworm.
2. Protozoa
• Protozoa are microscopic unicellular eukaryotes that have a relatively
complex internal structure and carry out complex metabolic activities.
• Some protozoa have structures for propulsion or other types of
movement.
3. Rotifers
• Rotifers are microscopic aquatic animals of the phylum Rotifera.
• Rotifers can be found in many freshwater environments and in moist soil,
where they inhabit the thin films of water that are formed around soil
particles.
4. Fungi
• Fungus, plural fungi, any of about 144,000 known species of organisms of
the kingdom Fungi, which includes the yeasts, rusts, smuts, mildews,
molds, and mushrooms.
• There are also many funguslike organisms, including slime molds and oomycetes
(water molds), that do not belong to kingdom Fungi but are often called fungi.
5. Bacteria
• Bacteria are small single-celled organisms. Bacteria are found almost everywhere
on Earth and are vital to the planet's ecosystems.
• Some species can live under extreme conditions of temperature and pressure.
• The human body is full of bacteria, and in fact is estimated to contain more
bacterial cells than human cells.
7. Algae
• Algae are defined as a group of predominantly aquatic, photosynthetic, and nucleus-
bearing organisms that lack the true roots, stems, leaves, and specialized
multicellular reproductive structures of plants.
8. Actinomyces
• Actinomyces is a genus of the Actinomycetia class of bacteria. They all are Gram-
positive.
• Actinomyces species are facultatively anaerobic (except A. meyeri and A. israelii are
obligate anaerobes), and they grow best under anaerobic conditions.

Unit 3:
Physical properties of soil:
1. Morphology
• Soil morphology is the study of the formation and description of soil types within
various soil horizons.C.F. Marbut championed reliance on soil morphology instead of
on theories of pedogenesis for soil classification because theories of soil genesis are
both ephemeral and dynamic.
• Observable attributes typically analyzed in the field include the composition, form,
soil structure and organization of the soil. Color of the base soil and features such as
mottling, distribution of roots and pores, consistency of the soil and evidence of
mineral presence also contribute to the classification.
• The observations are typically performed on a soil profile in order to analyze the
various soil horizons.
• Soil horizons are different layers of a soil profile that are characterized by different
properties obtained from various soil forming processes.
• Horizon - layer that is dominated by organic material, usually from plant or animal
litter. This horizon is subject to rapid change, and thus not usually used in the
description of a soil.
• A Horizon - Layer formed just below the O horizon, usually referred to as the topsoil.
This layer is a mineral horizon that has been darkened by organic matter [3]
• E Horizon - Mineral horizon that is characterized by the loss of oxides, iron, and clay
through the process of leaching, also known as eluviation. Usually has a high
concentration of sand and silt particles as the clay is leached out. [1]
• B Horizon - Mineral horizon that is defined by the materials that have accumulated
from the above horizons. The minerals and oxides that were lost to eluviation in the
above E horizon illuviate into this layer.[1]
• C Horizon - Layer that is most representative of the soil’s parent material. Made up
of semi-weathered material that is between soil and rock. This is the layer that holds
the most biological activity
• R Layer - Unconsolidated bedrock
2. Texture
• Soil texture (such as loam, sandy loam or clay) refers to the proportion of sand,
silt and clay sized particles that make up the mineral fraction of the soil. Soil
texture is determined with one of the following methods.
• Mechanical sieving, if particle size > 0.05 mm
• Sedimentation if size < 0.05 mm. Sedimentation measures the settling rate of
particles in liquid medium and relates this rate to the particle mass by use of the
Stoke's Law.
• Forces acting on soil particle are gravitation, buoyancy and drag forces, all of
which depend on particle size. Larger particles settle first. The particle mass is
determined by density and particle size.

• Soils must be dispersed prior to measurement. Two methods are commonly
used. Hydrometer method Pipette method. \
3. Soil structure
• Soil structure describes the arrangement and organization of soil particles in the soil,
and the tendency of individual soil particles to bind together in aggregates.
Aggregation affects water and air transport, which affects the movement of solutes
and pollutants and affects biologic activity, including plant growth.
• The development of soil structure is influenced by
• the amount and type of clay, as well as the exchangeable ions on the clay;
• the amount and type of organic matter, which provides food for soil fungi and
bacteria and their secretion of cementing agents (polysaccharides);
• the presence of cementing agents such as iron and aluminum oxides; and
• vegetation, which produces organic matter and binds soil particles together through
rooting.
4. Soil density
• Soil density is related to the mineral and organic composition of a soil and to soil
structure.
• The standard measure of soil density is bulk density, defined as the proportion of
the weight of a soil relative to its volume.
• It is expressed as a unit of weight per volume, and is commonly measured in
units of grams per cubic centimeter (g/cm3).
5. Soil Porosity (water and air)
• Pore space is that part of the bulk volume of soil that is not occupied by either
mineral or organic matter but is open space occupied by either gases or water.
• As discussed above, soil porosity is inversely related to bulk density. In a productive,
medium-textured soil the total pore space is typically about 50% of the soil volume.
Ranges for soil porosity are shown in the adjacent table.
• Although porosity does not vary widely across soil textures, values for porosity
minus field capacity vary widely, with greater values for coarse-textured soils (e.g.
sands).
6. Soil temperature
• Soil temperature is affected by climate, water content of a soil, soil color, soil cover
(e.g. presence or absence of mulch), depth in the soil profile, and air and water flow
within a soil. Minnesota soils are generally slow to warm in spring due to climate,
but the following conditions affect temperature.
• Dark colored soils warm more quickly and attain higher temperatures than light
colored soils
• Organic matter imparts a darker color to soil, leading to increased warming, but also
retains water, which can slow warming
• Soils with high porosity and well connected pores will warm faster and cool quicker
• Soils on south facing slopes are subject to greater thermal inputs compared to north
facing soils

• Soil temperatures fluctuate less with depth in the soil profile
• Soil temperatures fluctuate daily
7. Soil color
• Soil color is largely determined by the organic matter content, drainage conditions,
degree of oxidation, and in some cases, presence of specific minerals. Soil color is
not a widely used factor in stormwater applications.
8. Aggregate stability
• aggregate stability refers to the ability of soil aggregates to resist disintegration
when disruptive forces associated with tillage and water or wind erosion are
applied.
• Stable soil aggregates, in the presence of water, are important for water and air
transport, root growth, habitat for soil biota, minimizing soil erodibility, protecting
soil organic matter, and nutrient cycling.
Chemical properties of soil
• Soil chemical properties are important in planning fertigation. pH has a great effect
on the availability of residual nutrients in soil as well as on those added via
fertigation. The balance between cation and anion uptake by the plant affects the
pH in the rhizosphere.
1. Soil colloid
• They are included in day. formation of soil. These are tiny particles with unusual
chemical properties.
• Collid may be organic or mineral together two types make clay hummus complex.
• Clay minerals are in state continuous chemical change which is fundamental to soil
formation, so they are great importance.
2. Bases
• Clay minerals are overall negatively charged They are neutralized by the attraction
to their surface positively charged ions(cations) of calcium, magnesium, potassium
and sodium .These are called bases.
• They are only held loosely in an exchangeable position by clay minerals and maybe
given up in the process of base exchange to plant which require them for growth.
• The Metallic cations such as potassium, sodium tend to replace by hydrogen ion.
• Over the period of time this makes soil more acidic,unless bases are replenished in
some way.
• Soft calcareous rocks are often naturally fertile because rate of weathering of
calcium in parent material is sufficient to replace the loss of leaching of
exchangeable calcium Lime helps to preserve structural stability of soil.
3. Soil acidity
• It is property related to the proportion of exchangeable hydrogen in the soil in
relation to other elements.

• The degree of acidity is measured on the logithmic pH scale which range from 0
(extremely acidity) to 14 (extreme alkalinity).
• A pH value of about 6.5 is normally regarded as most favourable for growth of
cereal crops.
• The most important effect of pH in the soil is on ion solubility, which in turn affects
microbial and plant growth. A pH range of 6.0 to 6.8 is ideal for most crops because
it coincides with optimum solubility of the most important plant nutrients.
4. Soil color
• The colour of soil is determined with the aid of a Munsell color chart.
• Range from white to black - depend on amount of humus.
• Cool humid area - high humus- black or Brown colour soil.
• Desert - little humus-light Brown or Grey.
• In well aerated soils, oxidized or ferric (Fe+3) iron compounds are responsible for
the brown, yellow, and red colors you see in the soil. So reddish colour is due to
presence of ferric compound in well drained soil.
• When Iron is reduced to the ferrous (Fe+2) form, it becomes mobile, and can be
removed from certain areas of the soil. When the iron is removed, a gray color
remains, or the reduced iron color persists in shades of green or blue.Grey or bluish
colour- reduce iron compound Fe(OH)2 -indicating poor draining soil.
Soil reaction
• Many chemical properties of soils centre round the soil reaction. As regards their
nature, some soils are neutral, some are acidic and some basic. The acidity, alkalinity
and neutrality of soils are described in terms of hydrogen ion concentrations or pH
values. In order to understand soil reaction, the knowledge of pH is very necessary.
Soil erosion
• Soil erosion is the denudation of the upper layer of soil. It is a form of soil
degradation.
• This natural process is caused by the dynamic activity of erosive agents, that is,
water, ice (glaciers), snow, air (wind), plants, and animals (including humans).
• In accordance with these agents, erosion is sometimes divided into water erosion,
glacial erosion, snow erosion, wind (aeolean) erosion, zoogenic erosion and
anthropogenic erosion such as tillage erosion.
• Soil erosion may be a slow process that continues relatively unnoticed, or it may
occur at an alarming rate causing a serious loss of topsoil.
• The loss of soil from farmland may be reflected in reduced crop production
potential, lower surface water quality and damaged drainage networks.
• Soil erosion could also cause sinkholes.

1. Physical processes
• Rainfall and surface runoff
• Rivers and streams
• Floods
• Wind erosion
• Mass movement
• Tillage erosion

2. Factors affecting soil erosion
• Climate
• Soil structure and composition
• Vegetative cover
• Topography

3. Human activities that aid soil erosion
• Agricultural practices
• Deforestation
• Roads and human impact
• Climate change

4. Global environmental effects
• Land degradation
• Sedimentation of aquatic ecosystems
• Airborne dust pollution
Prevent and conserve
• The most effective known method for erosion prevention is to increase vegetative
cover on the land, which helps prevent both wind and water erosion.
• Terracing is an extremely effective means of erosion control, which has been
practiced for thousands of years by people all over the world.
• Windbreaks (also called shelterbelts) are rows of trees and shrubs that are planted
along the edges of agricultural fields, to shield the fields against winds. In addition to
significantly reducing wind erosion, windbreaks provide many other benefits such as
improved microclimates for crops (which are sheltered from the dehydrating and
otherwise damaging effects of wind), habitat for beneficial bird species, carbon
sequestration,and aesthetic improvements to the agricultural landscape.
• Traditional planting methods, such as mixed-cropping (instead of monocropping)
and crop rotation have also been shown to significantly reduce erosion rates.

• Crop residues play a role in the mitigation of erosion, because they reduce the
impact of raindrops breaking up the soil particles. There is a higher potential for
erosion when producing potatoes than when growing cereals, or oilseed crops.
• Forages have a fibrous root system, which helps combat erosion by anchoring the
plants to the top layer of the soil, and covering the entirety of the field, as it is a
non-row crop.
• In tropical coastal systems, properties of mangroves have been examined as a
potential means to reduce soil erosion. Their complex root structures are known to
help reduce wave damage from storms and flood impacts while binding and building
soils. These roots can slow down water flow, leading to the deposition of sediments
and reduced erosion rates. However, in order to maintain sediment balance,
adequate mangrove forest width needs to be present.
Soil degradation
• Soil degradation describes what happens when the quality of soil declines and
diminishes its capacity to support animals and plants. Soil can lose certain physical,
chemical or biological qualities that underpin the web of life within it.
• Soil erosion is a part of soil degradation. It's when the topsoil and nutrients are lost
either naturally, such as via wind erosion, or due to human actions, such as poor
land management.
How degradation takes place
• Soil is not an inert medium but a living ecosystem that is essential to life. It takes
hundreds and thousands of years to form an inch of topsoil, and many more
centuries before it is fertile.
• While soil degradation is a natural process, it can also be caused by human activity.
In the last few decades, soil degradation has been sped up by intensive farming
practices like deforestation, overgrazing, intensive cultivation, forest fires and
construction work.
• Silvia says, 'Several practices associated with intensive agriculture, especially tilling,
disrupt soil structure. They accelerate surface runoff and soil erosion, loss of organic
matter and fertility and disruption in cycles of water, organic carbon and plant
nutrients. These practices also have a major negative impact on soil biodiversity.
• It also reduces the amount of carbon the soil can store by 50-75%.
• Soil compaction occurs when there is a combination of wet soil and a heavy weight,
for example unwieldy machinery in farming. Networks of tunnels and pores created
by various organisms collapse beneath the pressure and air is squeezed out,
threatening underground habitats and the availability of nutrients. Tilling soil also
has similar results.
• Salination - salty water - is a result of excessive irrigation or extraction of
groundwater in coastal areas. This can make some bacterial species inactive and can
kill many other microorganisms.

• Without underground life, land would become barren. In a worst-case scenario, it
can lead to desertification, where the soil is damaged beyond repair and nothing
grows except a handful of plants that can handle very harsh conditions.
• increasing urbanisation also has a negative impact. This results in the death of
millions of microorganisms and can lead to water runoff in other areas where it may
cause flooding and erosion.
• Soil degradation can have disastrous effects around the world such as landslides and
floods, an increase in pollution, desertification and a decline in global food
production. One of the biggest threats to our future food security is land
degradation and the associated loss in soil productivity.
Solution
• These include simple acts such as leaving vegetation on soil to allow nutrients to
return into the earth.
• Communities, farmers and corporations can be educated about sustainable
practices to promote respect and responsibility for nature and reduce their carbon
footprint.
• Education can also encourage individuals to grow their own produce, which can
foster a curiosity and appreciation for nature, as well as motivate to protect the
planet. It also alleviates some of the pressure experienced by farms to support an
ever-growing population.
• Other changes may be harder to establish, such as avoiding monocultures (growing
one single crop in a large area), because that would require lots of farmers to
overhaul the way they work.
• However, monocultures can be extremely damaging to the soil - growing the one
type of plant in one area of soil means the same nutrients are continuously being
absorbed, which eventually leads to depletion.
• Farmers often end up using chemical products to fight pests and diseases, and
fertilisers to try and encourage crops to continue growing.
• Practicing crop rotation allows different plants to grow in an area of soil every year.
This allows the soil to replenish itself of nutrients that are lacking after the growth of
one type of plant.
• Agroforestry involves growing crops around trees and other plants such as hedges.
Trees create their own microclimate, which is favourable for crops. They also act as
a form of protection against wind and water damage and encourage biodiversity,
which keeps ecosystems strong and healthy.
• Permaculture is a form of sustainable farming that respects nature and its design. It
incorporates practices such as creating an integrative space where beneficial
relationships between different organisms can flourish, and avoiding unnatural
substances and waste.

Soil conservation
1 Contour ploughing: Contour ploughing orients furrows following the contour
lines of the farmed area. Furrows move left and right to maintain a constant
altitude, which reduces runoff. Contour ploughing was practiced by the
ancient Phoenicians for slopes between two and ten percent.
[4]
Contour ploughing
can increase crop yields from 10 to 50 percent, partially as a result of greater soil
retention.
2 Terrace farming: Terracing is the practice of creating nearly level areas in a hillside
area. The terraces form a series of steps each at a higher level than the previous.
Terraces are protected from erosion by other soil barriers. Terraced farming is
more common on small farms.
3 Keyline design: Keyline design is the enhancement of contour farming, where the
total watershed properties are taken into account in forming the contour lines.
4 Perimeter runoff control: Tree, shrubs and ground-cover are effective perimeter
treatment for soil erosion prevention, by impeding surface flows. A special form of
this perimeter or inter-row treatment is the use of a "grass way" that
both channels and dissipates runoff through surface friction, impeding surface
runoff and encouraging infiltration of the slowed surface water.
5 Windbreaks: Windbreaks are sufficiently dense rows of trees at
the windward exposure of an agricultural field subject to wind erosion.
Evergreen species provide year-round protection; however, as long as foliage is
present in the seasons of bare soil surfaces, the effect of deciduous trees may be
adequate.
6 Cover crops/crop rotation: Cover crops such as legumes plant, white turnips,
radishes and other species are rotated with cash crops to blanket the soil year-
round and act as green manure that replenishes nitrogen and other critical
nutrients. Cover crops also help suppress weeds
7 Soil-conservation farming
8 Salinity management
9 Soil organisms
10 Mineralization: To allow plants full realization of their phytonutrient potential,
active mineralization of the soil is sometimes undertaken. This can involve adding
crushed rock or chemical soil supplements. In either case the purpose is to combat
mineral depletion. A broad range of minerals can be used, including common
substances such as phosphorus and more exotic substances such as zinc and
selenium. Extensive research examines the phase transitions of minerals in soil with
aqueous contact.

Unit 4:
Evaluation of land and soil
• Land evaluation is mainly the analysis of data about land containing soils, climate,
vegetation, an so forth, in terms of realistic alternatives for improving the use of the
land. Two types or trends qualitative and quantitative
• The evaluation of the soils intrinsic potential should be related to inherent soil
properties and site conditions (i.e., texture, mineralogy, soil depth, climate) since all
that can be affected by soil management is only relevant for reaching this potential
and, thus, cannot be part of its definition.
Parametric system of land and soil
• Parametric systems find their origin in field trials and fertility tests, especially
where a good correlation could be found between crop yield and one or more
key land factors. Parametric systems like all numerical correlations are a simple
quantified expression of soil productivity.
• Their reliability depends, however, heavily on the choice of the factor
determinants, their weighting, and the validity of the assumed interactions
between the factors.
• Storex index- The Storie index was originally devised for the agricultural rating of
citrus soils in California, in particular for taxation purposes. The first edition of
the index appeared in the 1930s, but it has frequently been revised, even up till
1978. Adaptations of the system have also been used in many other parts of the
world.
• The Riquier, Bramao and Cornet System: In 1970 Riquier and collaborators
developed a parametric system of soil appraisal in terms of actual and potential
productivity. This approach involves the calculation of a productivity index on the
basis of nine factors, each of which is given a numeric value from 1 to 100. The
resultant index obtained by a multiplication of those factors is positioned in one
of the 5 productivity classes. The factors involved refer to moisture status (H ),
drainage (D ), effective depth (P ), texture and structure (T ), base saturation ( N
), soluble salt concentration (S ), organic matter content (O), mineral exchange
capacity and type of clay (A ) and mineral reserve (M ).
Non parametric system of land and soil (youtube)
Land capability classfification
a. Definition. Land capability classification is a system of grouping soils primarily on the
basis of their capability to produce common cultivated crops and pasture plants without
deteriorating over a long period of time.
b. Classes. Land capability classification is subdivided into capability class and capability
subclass nationally. Some states also use a capability unit.

c. Significance. Land capability classification has value as a grouping of soils. National
Resource Inventory information, Farmland Protection Policy Act, and many field office
technical guides have been assembled according to these classes. The system has been
adopted in many textbooks and has wide public acceptance. Some state legislation has
used the system for various applications. Users should reference Agriculture Handbook
No. 210 (Exhibit 622-2 ) for a listing of assumptions and broad wording used to define the
capability class and capability subclass.
d. Application. All map unit components, including miscellaneous areas, are assigned a
capability class and subclass. Agriculture Handbook No. 210 (Exhibit 622-2 ) provides
general guidance, and individual state guides provide assignments of the class and
subclass applicable to the state. Land capability units can be used to differentiate
subclasses at the discretion of the state. Capability class and subclass are assigned to map
unit components in the national soil information system.
e. Categories:
1. Capability Class:
Definition. Capability class is the broadest category in the land capability classification
system. Class codes I (1), II (2), III (3), IV (4), V (5), VI (6), VII (7), and VIII (8) are used to
represent both irrigated and nonirrigated land capability classes.
1 Classes and definitions:
• Class I (1) soils have slight limitations that restrict their use.
• Class II (2) soils have moderate limitations that reduce the choice of plants or
require moderate conservation practices.
• Class III (3) soils have severe limitations that reduce the choice of plants or require
special conservation practices, or both.
• Class IV (4) soils have very severe limitations that restrict the choice of plants or
require very careful management, or both.
• Class V (5) soils have little or no hazard of erosion but have other limitations,
impractical to remove, that limit their use mainly to pasture, range, forestland, or
wildlife food and cover.
• Class VI (6) soils have severe limitations that make them generally unsuited to
cultivation and that limit their use mainly to pasture, range, forestland, or wildlife
food and cover.
• Class VII (7) soils have very severe limitations that make them unsuited to cultivation
and that restrict their use mainly to grazing, forestland, or wildlife.
• Class VIII (8) soils and miscellaneous areas have limitations that preclude their use
for commercial plant production and limit their use to recreation, wildlife, or water
supply or for esthetic purposes.

Soil Reclamation
Soil Reclamation is the process of reclaiming the soil’s quality like lost fertility, minerals,
nutrients and moisture to make it fit for intensive use again. The reclamation of soil, its
nutrients and fertility are done with an objective to increase further land use and enhance
agricultural activities like cropping and irrigation.
This process in combination with Land reclamation is being employed widely for the
creation of national parks and wildlife sanctuaries for enhancing wilderness and forest life
by a combined process called Pedogenesis.
Pedogenesis, also known as soil development, soil evolution, soil formation, and soil
genesis, is the process of soil formation as regulated by the effects of place, environment,
and history.
Methods of Soil Reclamation
Soil Reclamation is carried out for the development of layers, termed soil horizons,
distinguished by differences in color, structure, texture, and chemistry. These features
occur in patterns of soil type distribution, forming in response to differences in soil
forming factors.
There are numerous Biological, Chemical and Biogeochemical processes are employed to
execute Soil Reclamation through Pedogenesis. Methods used for soil reclamation
depend on the quality of the soil and objective of soil reclamation. Different types of soils
include:
• Arid land
• Wetlands
• Swampy lands
• Salt-affected soil
• Mining area soil
The most popular methods used for soil reclamation are:
• Phytoremediation
• In this method, higher plants are used for the degradation and removal of different
contaminants (both organic and inorganic) from the soil. Among these methods, the
most frequently used are:
Phytostabilization
• This process is based on the ability of roots to immobilize pollutants. The process
takes place on the surface of roots as an adsorption effect. Contaminants are
absorbed into roots and precipitated in the roots’ area.
Phytoextraction/Photodegradation

In this method, contaminants are picked up by the roots of plants and transported to their
overground parts, and then removed together with the crops.
• Bioremediation
• This method is based on microorganisms’ activity, which is commonly used for the
reclamation of soils polluted by organic compounds. However, recently there have
also been many investigations into applying microorganisms for detoxication and
cleaning soil polluted by inorganic substances.
• Electroremediation
• This method is based on the phenomenon of pollutant migration in an electric field.
Migrating particles have to have a permanent electric charge or have to be
polarized, so the technique is used to remove heavy metals or polar compounds.
Electrodes are inserted into the ground on opposite sites of the contaminated area.
• Contaminants under the influence of an electromagnetic field migrate through the
soil within the cathode or anode area, where they are removed in a few possible
ways: chemical precipitation, adhesion to the electrodes’ surfaces, removing and
processing the contamination beyond the remediated site.
• Biofiltration
• Biological filters and bioreactors are based on the biological activity of
microorganisms. During the first stage of the process, the contaminated soil is mixed
with water and as a suspension is moved into a reaction chamber where a selected
group of microorganisms removes the contaminants as a result of sorption and/or
transformation.
• Surface Insulation
• This is a physical method based on covering the contaminated soil to prevent toxic
migration to the environment as a result of rainwater or wind erosion. The layers
are comprised of a combined material such as synthetic fiber, clay, and concrete.
• Hydraulic method (Soil washing)
• This method is used for removing inorganic contamination, such as heavy metals,
radionuclides, toxic anions and others. In some cases, it can be applied to organic
contamination. This method uses a wide spectrum of leaching solutions from water
to strong inorganic acids.
• Air Sparging
• This is a subsurface contaminant remediation technique that involves the injection
of pressurized air into the contaminated groundwater causing hydrocarbons to
change state from dissolved to vapor state. The air is then sent to the vacuum
extraction systems to remove the contaminants.
• Composting

• Contaminated soil is explored and stored in a pile or a thin layer distributed over a
larger area, for the degradation of contaminants.
• This process enables some organic contaminants (oil origin compounds, non-
halogen compounds and some of the halogen compounds and pesticides) to be
removed from the soil, by way of biological degradation. The process is carried out
by aerobic organisms, which mineralize organic compounds to simple compounds
such as CO2, H2O, and others.
Soil management
• Soil management is the application of operations, practices, and treatments to
protect soil and enhance its performance (such as soil fertility or soil mechanics). It
includes soil conservation, soil amendment, and optimal soil health. In agriculture,
some amount of soil management is needed both in nonorganic and organic types
to prevent agricultural land from becoming poorly productive over decades. Organic
farming in particular emphasizes optimal soil management, because it uses soil
health as the exclusive or nearly exclusive source of its fertilization and pest control.
• Soil management is an important tool for addressing climate change by increasing
soil carbon and as well as addressing other major environmental issues associated
with modern industrial agriculture practices. Project Drawdown highlights three
major soil management practices as actionable steps for climate change mitigation:
improved nutrient management, conservation agriculture (including No-till
agriculture), and use of regenerative agriculture.
Environmental impact
• According to the EPA, agricultural soil management practices can lead to production
and emission of nitrous oxide (N2O), a major greenhouse gas and air pollutant.
Activities that can contribute to N2O emissions include fertilizer usage, irrigation
and tillage. The management of soils accounts for over half of the emissions from
the Agriculture sector. Cattle livestock account for one third of emissions, through
methane emissions. Manure management and rice cultivation also produce
emissions.[4] Using biochar may decrease N2O emissions from soils by an average of
54%.[5] the usage of artificial fertilizer in the agricultural field it leads to nutrition
imbalance in the soil.
• Soils can sequester carbon dioxide (CO2) from the atmosphere, primarily by storing
carbon as soil organic carbon (SOC) through the process of photosynthesis. CO2 can
also be stored as inorganic carbon but this is less common. Converting natural land
to agricultural land releases carbon back into the atmosphere. The amount of
carbon a soil can sequester depends on the climate and current and historical land-
use and management.[6] Cropland has the potential to sequester 0.5–1.2 Pg C/year
and grazing and pasture land could sequester 0.3–0.7 Pg C/year.[7] Agricultural
practices that sequester carbon can help mitigate climate change.[8] Intensive
farming deteriorates the functionality of soils.

• Methods that significantly enhance carbon sequestration in soil include no-till
farming, residue mulching, cover cropping, and crop rotation, all of which are more
widely used in organic farming than in conventional farming.[9][10] Because only 5%
of US farmland currently uses no-till and residue mulching, there is a large potential
for carbon sequestration.
Practices
Specific soil management practices that affect soil health include:[17]

• Controlling traffic on the soil surface helps to reduce soil compaction, which can
reduce aeration and water infiltration.
• Planting cover crops that keep the soil anchored and covered in off-seasons so that
the soil is not eroded by wind and rain.
• Crop rotations[18] for row crops alternate high-residue crops with lower-residue
crops to increase the amount of plant material left on the surface of the soil during
the year to protect the soil from erosion.
• Nutrient management can help to improve the fertility of the soil and the amount of
organic matter content, which improves soil structure and function.
• Tilling the soil, or tillage, is the breaking of soil, such as with a plough or harrow, to
prepare the soil for new seeds. Tillage systems vary in intensity and disturbance.
Conventional tillage is the most intense tillage system and disturbs the deepest level
of soils. At least 30% of plant residue remains on the soil surface in conservation
tillage.[19][20] Reduced-tillage or no-till operations limit the amount of soil
disturbance while cultivating a new crop, and help to maintain plant residues on the
surface of the soil for erosion protection and water retention.
• Adding organic matter to the soil surface can increase carbon in the soil and the
abundance and diversity of microbial organisms in the soil.[21][22]
• Using fertilizers increases nutrients such as nitrogen, phosphorus, sulfur, and
potassium in the soil. The use of fertilizers influences soil pH and often acidifies
soils, with the exception of potassium fertilizer.[23] Fertilizers can be organic or
synthetic.
Sources of soil or land degradation
1. Overgrazing, Deforestation and Careless Forest Management
2. Urban Growth, Industrialization and Mining
3. Natural and Social Sources of land Degradation
4. Land Shortage, Land Fragmentation and Poor Economy
5. Population Increase
Agricultural Activities Leading to Land Degradation in India
1. Low and Imbalanced Fertilization
2. Excessive Tillage and Use of Heavy Machinery

3. Crop Residue Burning and Inadequate Organic Matter Inputs
4. Poor Irrigation and Water Management
5. Poor Crop Rotations
6. Pesticide Overuse and Soil Pollution
Strategies to Mitigate Land Degradation
1. Soil Erosion Control
2. Water Harvesting, Terracing and Other Engineering Structures
3. Landslide and Minespoil Rehabilitation and River Bank Erosion Control
4. Intercropping and Contour Farming
5. Subsoiling
6. Watershed Approach
7. Integrated Nutrient Management and Organic Manuring
8. Reclamation of Acid and Salt Affected Soils and Drainage (Desalinization)
9. Remediation of As Contamination
10. Water Management and Pollution Control
11. Irrigation Management for Improving Input Use Efficiency
12. Reforestation, Grassland and Horticulture Development
13. Agroforestry
14. Conservation Agriculture
15. Intensive Cropping, Diversified Cropping and Integrated Farming Systems
16. Disaster (Tsunami) Management
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