PRESENTED BYDr. Radhey Shyam

Assist. Professor-cum-Jr. Scientist (Agronomy)Bhola Paswan Shastri Agricultural College, Purnea

soil conditioners/Amendments

Introduction

• A soil conditioner, also called a soil amendment, is a material added to soil to improve plant growth and health.

• The type of conditioner added depends on the current soil composition, climate and the type of plant.

• A conditioner or a combination of conditioners corrects the soil's deficiencies.

• Fertilizers, such as peat, manure, anaerobic digestate or compost, add depleted plant nutrients.

• Gypsum releases nutrients and improves soil structure.

Characteristics of soil conditioners

• Soil conditioners are natural and earthy.

• Absorb water rapidly.

• Compost is “Synthetic manure made from decomposing

materials, fertilizer and soil.

• Leaves and manures are also natural products.

Function of soil conditioners

• They help to improve the amount of minerals in the soil.

• Soil that is rich in minerals will produce much healthier vegetation.

• Leaves work by attracting earthworms which create a healthy soil .

• Soil improved by

• Physical

• Chemical

• Biological

Importance of soil conditioners

• Soil conditioner is a product which is added to soil to improve the soil

quality.

• Soil conditioners can be used to rebuild soils which have been damaged

by improper management, to make poor soils more usable, and to

maintain soils in peak condition.

• A wide variety of products can be used to manage soil quality, with most

being readily available from nurseries and garden supply stores.

• People can also generate their own soil conditioner with materials from

home.

Importance of soil conditioners

• Many soil conditioners are designed to improve soil structure in some

way.

• Soils tend to become compacted over time, which is bad for plants,

and soil conditioners can add more loft and texture to keep the soil

loose.

• They also add nutrients , enriching the soil and allowing plants to

grow bigger and stronger.

• Soil conditioners improve the water retention in dry, coarse soils

which are not holding water well, and they can be added to adjust the

PH of the soil to meet the needs of specific plants or to make highly

acidic or alkaline soils more usable.

Soil physical conditions and soil conditioners

• Soil physical condition is one factor that can limit

crop production.

• Poor soil physical condition can restrict water

intake into the soil and subsequent movement,

plant root development, and aeration of the soil.

• These goals can be accomplished in part through

the use of good management techniques.

• Producers and researchers alike are interested in

improving the physical condition of the soil and,

thus, enhance crop production.

Vital role of soil conditioners

• Improved soil structure and aeration

• Increased water-holding capacity.

• Increased availability of water to plants

• Reduced compaction and hardpan conditions.

• Improved tile drainage effectiveness

• Alkali soil reclamation

• Release of “locked” nutrients

• Better chemical incorporation

• Better root development

• Higher yields and quality

Role of soil conditioners/Amendments under INM

• Soil conditioners may be used to improve water retention in dry,

coarse soils which are not holding water well, and they can be added

to adjust the pH of the soil to meet the needs of specific plants or to

make highly acidic or alkaline soils more usable.

Examples of soil conditioners

• Peat

• Compost

• Coir

• Manure

• Straw

• Vermiculite etc.,

Types and use of soil conditioners/amendments

Types

Organic soil conditioners Inorganic(Synthetic) soil conditioners

Types and use of soil conditioners/amendments

Organic

Green Manure

Compost

Peat

Crop Resides

Coconut shell mulch

Types of Organic soil conditioners

Organic Soil Conditioners Organic Soil Conditioners

• Soil organic matter serves as a reservoir for nutrients;

• Improves soil structure ,

• Drainage,

• Aeration,

• Cation exchange capacity,

• Buffering capacity, and water-holding capacity; and provides a source of

food for microorganisms.

• Generally soils having higher in organic matter have improved soil physical

conditions.

• The effectiveness of organic soil conditioners can be partly evaluated by

examining several properties of soil organic matter.

Organic Soil Conditioners

• Soil organic matter is defined as the organic fraction of the soil and

includes plant and animal residues at various stages of

decomposition, cells and tissues of organisms, and compounds

synthesized by the soil organism population.

• Soil organic matter contains a wide array of compounds ranging

from fats, carbohydrates, and proteins to high molecular weight

humic and fulvic acids.

Green manure Green manure

• GM is a crop that is grown mainly to add nutrients and organic matter to the

soil, this kind of crop is used in rotation with other crops, which is ploughed

under to serve the same purposes as animal manure.

• The roots of some green manure grow deep into the soil and bring up nutrients

that are not present in shallow rooted crops.

• Leguminous crops are especially favored as green manures because they add

nitrogen to the soil.

The green manure crop should possess the following desirable

characteristics :

• have profuse leaves and rapid growth early in its life cycle.

• have abundance and succulent tops

• be capable of making a good stand on poor and exhausted soils.

• have a deep root system.

• be legume with good nodular growth habit

Green manuring

• Supply Organic Matter

• Green manure supplies organic matter to the soil.

• The organic residues from green manure also help to provide the stability of soil structure needed for optimum plant growth.

• Humus formed from green manure increases the absorptive capacity of soil, promotes aeration, drainage and granulation, which help the plant growth.

• Green manuring improves the structure of the soil. Organic matter stimulates the activity of soil micro-organisms.

• The ability to bind contaminants is exhibited when using organic soil mulches in construction of filter germs.

Addition of Nitrogen:

•The green manuring crop supplies additional nitrogen to organic

matter, if it is a legume crop, which has the ability to fix nitrogen from

the air with the help of its root nodule bacteria (e.g. Rhizobium).

•The legume crop adds nitrogen for the succeeding crop.

•So all the legumes crop leave the soil in better physical condition and

richer in nitrogen content.

•They return the plant nutrients of deeper layers to the upper top soil

Nutrient and Soil Conservation

•Green manuring crops act as cover crop.

• They protect the soil from erosion and nutrient loss by taking up soluble

nutrients which might otherwise have been lost in drainage water or due to

erosion.

• Green manuring crops make available phosphorous and other nutrients

fort he succeeding crops.

• Green manure has a marked residual effect also.

• Increases the biochemical activity.

• The organic matter added to soil by way of green manure acts as food for

micro-organisms.

• The organic matter stimulates the activity of micro-organisms and they

stimulate the biochemical changes accordingly.

Green manuring increases crop yield:

• Green manure increases the organic matter and nitrogen content

(in case of leguminous green manuring crop) of the soil.

• It is proved that if green manuring is done properly, it always

results in increased yields of the succeeding crops.

Compost

• Composting is comes naturally to plant materials.

• They return to the earth to supply nutrients for the next cycle of

seeds.

• kitchen scraps can be recycled and yard waste composting them.

• Instead of throwing out produce scraps, egg shells and coffee

grounds, can be compost of along with the leaves raked up and

the dead plants cleared out of the garden.

Importance of composting

• Improve the soil quality to reap their benefits and vitality by releasing

the rich nutrients in the compost into the soil

• Prevent greenhouse gas emissions by encouraging the aerobic

breakdown of organic material and reduces the amount of garden

and kitchen waste going to Landfill.

• Recycle valuable nutrients and reduce the use of artificial fertilizers

Importance of composting

• Adding raw material to compost

• Vegetable and food scraps

• Fallen leaves (in layers)

• Tea leaves and tea bags Sawdust

• Coffee grounds , Egg shells, Weeds, Wood ash

• Compost and organic soil mulches instead of more conventional

methods sediment control are numerous.

• Probably the two greatest benefits of using compost as a soil mulch in

sediment control

• immediate effectiveness

• its ability to bind and degrade specific contaminants.

Compost Compost

• Compost is made by forming

alternate layers of organic matter

and soil, commercially made

fertilizer can also be added to the

compost.

Carbon

Nitrogen

Oxygen

Water

Components needed during CompostingComponents needed during Composting

Components needed during CompostingComponents needed during Composting

• Decomposition can take place even without these ingredients, but the

process can be slow and unpleasant.

• Vegetables, if decomposed in plastic bag, will develop a foul smell

Home compost

• Composting is the controlled decomposition of organic material

such as leaves, twigs, grass clippings, and vegetable food

waste.

• Compost is the soil amendment product that results from proper

composting.

• composting helps to keep the high volume of organic material

out of landfills and turns it into a useful product

Compost

Application

• General application rates for compost or other organic soil amendments are

based on the salt content of the materials and soil and on the depth to which

it is cultivated into the soil.

• Ideally, cultivate the soil amendment into the top six to eight inches of the

soil.

• On compacted/clayey soils, anything less can lead to a shallow rooting

system with reduced plant growth, lower vigor, and lower stress tolerance.

• Compost, which includes manure or biosolids as a component, has a

potential for high salts

• Excessive salt levels are common in many commercially available products

sold in Colorado.

• Compost needs to be thoroughly mixed into the upper six to eight inches of the soil

profile.

• Do not leave compost in chunks, as this will interfere with root growth and soil

water movement.

• As the soil organic content builds in a garden soil, the application rate should be

reduced to prevent ground water contamination issues.

• A soil test is suggested every four to six years to establish a base line on soil

organic matter content If using a green manure cover crop, till the cover crop in

before it reaches four inches in height.

• In the vegetable garden do not plow in woody materials such as bark or

woodchips.

• They may interfere with seedbed preparation and may result in soil nitrogen

depletion.

Benefits of composting

• Compost that are stable in nature, possessing significant amounts

of humic acids, have the ability to bind nutrients and heavy metals,

as moisture passes through the product layer.

• Organisms found within compost have the ability to degrade organic

contaminants such as hydrocarbons found in petroleum based

materials.

• Green manure:

• The practice of ploughing or turning into soil under-composed green

plant tissue for the purpose of improving physical condition as well

as fertility of the soil is referred to as green manuring and the

manure obtained is known as green manure.

Peat

Consists of plant remains; it

improves soil structure

Crop Residues

•Crop residues contain substantial

quantities of plant nutrients.

Recycling of plant nutrients

•Soil moisture temperature regimes,

enhancement of soil structure,

erosion control

Crop Residues

• Leaves make dark, rich

compost that add nutrients to

your soil and help keep your

plants strong and disease

free.

• Fall cleanup is a great time to

start a compost pile and put

those leaves to work.

Approximate C: N ratios of organic material and soil microbes.Approximate C: N ratios of organic material and soil microbes.

SI.NO Crop Residues C:N Ratio1 Alfalfa (young) 13:12 Bluegrass 30:13 Maize Straw

40:1

4 Straw (small grain)

80:1

5 Sewage Sludge

10-12:1

6 Cattle Manure

30:1

7 Peat Moss

58:1

8 Sawdust Hardwood

295: 1

9 Hardwood 295: 110 Pine 729:1Soil Microbes11 Bacteria 5:112 Actinomycetes 6:113 Fungi 10:1

Source: Tnau agritech portal

Coconut shell mulch

• The mulching made from the

grinding up of coconut shells.

• its is extremely long lasting since

it comes from a tropical plant and

decomposes very slowly;

Coconut shell mulch Coconut shell mulch

• It has a very strong but pleasant odor which is suppose to keep

bugs and animals (dogs and cats) away from the plants it is

mulching.

Other Organic Fertilizers

• Include bird and bat droppings, blood meal, bone meal, and

fish meal.

Coconut shell mulch Coconut shell mulch

• All these substances contain nitrogen and other

essential elements

• Bone meal is an excellent source of the element

phosphorus.

• But blood meal, bone meal, and fish meal is seldom

used on farms as fertilizers, because it is too

expensive.

Types of Inorganic soil conditionersTypes of Inorganic soil conditioners

Inorganic

Synthetic Binding Agents

Mineral Conditioners

Gypsum

Types of Inorganic soil conditioners

Synthetic Binding Agents

• New polymers applied at much lower rates have been

promoted as soil conditioners.

• These polymers include

Natural polysaccharides,

Anionic

Cationic polymers,

polyacrylamides.

Synthetic Binding AgentsSynthetic Binding Agents

• The compounds are very high

• molecular weight,

• long-chain polymeric,

• organic compounds,

• which bind particles together and form stable

aggregates

Mineral Conditioners

• Gypsum has long been recognized for its benefits on

high sodium-containing soils.

• Gypsum is a mineral with the chemical composition

CaSO4 * 2H2O.

• It occurs in nature as soft crystalline rock and varies in

purity.

Mineral ConditionersMineral Conditioners

• Gypsum has been shown to displace exchangeable sodium from the

cation exchange sites of soils high in sodium

• With irrigation or dryland, gypsum can be used to reclaim saline

areas or slick spots, soften and crumble alkali hard pans, supply

calcium on low exchange capacity soils, and improve infiltration for

some puddled soils.

Mineral ConditionersMineral Conditioners

• Gypsum is not recommended on soils containing native gypsum

or areas irrigated with water containing abundant amounts of

calcium and magnesium

• The amount of gypsum to apply depends on the purity of the

gypsum and the quantity of sodium present in the soil.

• Actual rates should be based on a salt-alkali soil test.

Gypsum Gypsum

• Lowers bulk compactness of soil

• Prevents water run-off and eroding

• Betters Soil Composition

• It affords root growth and air and water movement.

• Converts Salty Soils

Gypsum Gypsum

• An economical method to resolve salty soils.

• Ties Organic Matter to Clay

• The importance of organic matter is magnified when it is

dispensed with gypsum.

• Soil crusting is impossible and then helps seed emersion.

Gypsum Gypsum

• No crust formation allows more and faster seed emergence

and a couple days earlier to harvest and market.

• Betters low dissolved matter Irrigation Water

• Develops water use efficiency

Gypsum Gypsum

• Gypsum helps the efficiency use of water for the crops. In

periods of drought, this is exceedingly important.

• Helps moist soils to be tilled easier

• Less energy is required for the tillage

Quantity of gypsum applied in mineral soil conditioners Quantity of gypsum applied in mineral soil conditioners

• 10 tons/acre.

• Gypsum applied at less than 500 pounds per acre

• Limestone, crushed rock, and other products high in calcium and/or

magnesium which improve the physical condition of some soils, when

applied at several tons per acre.

Let Us Sum Up

• Soil conditioners to improve agricultural land and increase productivity.

• Types of soil conditioners and their role , importance , function and usage are described.

•Farmers can adopt this technology to improve the crop production.