Soil conditioners as a source of plant nutrients has been found beneficial in improving Physical, Chemical and Biological conditions of soil, thereby increased productivity of crops.
If the soil had very low pH, P and extractable Si then it is necessary to use soil conditioners for improving soil pH and some elements such as P and Si. Farmers can adopt this technology to improve the crop production.
A soil conditioner is a product which is added to soil to improve the soil’s physical qualities, especially its ability to provide nutrition for plants. In general usage the term soil conditioner is often thought of as a subset of the category 'Soil Amendments' which more often is understood to include a wide range of fertilizers and non-organic materials.
Soil conditioners can be used to improve poor soils, or to rebuild soils, which have been damaged by improper management. All amendment are also called soil conditioners because they also improve the physical conditions of soil likewise conditioners.
Fly-ash, having both the soil amending and nutrient - enriching properties, is helpful in improving crop growth and yield in low fertility soils. It has been shown that FA based soil conditioner not only improves the crop productivity and soil fertility but also mobilizes macro- and micro nutrients in the soil.
Soil conditioners can make poor soils more usable, and can be used to maintain soils in peak condition. Soil physical condition is one factor that can limits the crop production. Poor soil physical condition can restricted the water intakes in to the soil and subsequent movement, plant root development and aeration of the soil
With the diversity of soil conditioner in the market today, it is important to understand the nature, use and practical benefits’ of these products.
Importance and function 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.
- 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.
- Improvement in physical, chemical and Biological conditions of soil.
- Significantly increased slope of soil moisture curve at its inflection point.
Types of Soil conditioners:
Soil conditioners are varying with their origin and composition. Soil conditioners can be synthetic or natural occurring organic and inorganic materials.
A wide variety of materials have been described as soil conditioners due to their ability to improve soil quality. Some examples include: biochar, bone, peat, coffee grounds, compost, coir, manure, straw, vermiculite, sulfur, lime, blood meal, compost tea, hydro absorbent polymers and sphagnum moss.
Organic soil conditioners:
Green manure, Crop residues, Peat, Crop residues, Coconut shell mulch, humus, sewage and sludge, vermicompost, Cattel manure, hamates etc. soil organic matter serves as a reservoir for nutrients.
They improve soil structure, Drainage, Aeration, Cation exchange capacity, Buffering capacity, and water-holding capacity and provides a source of food for microorganisms.
Animal manure: Partially decomposed plant material plus a wide variety of organism. It contains soluble salt which can be detrimental to soil physical properties and crop growth when added in high amount, especially to arid soil.
Sewage sludge: Effectiveness of the material varies with the amount of material added and C: N ratio. Sewage sludge may contain potentially harmful level of heavy metals and other toxic material and should be analysed for these material before using.
Humate: It reduces soil erosion by increasing the cohesive forces of the very fine soil particles. They improve soil structure and physical properties of soil by raising EC and buffering qualities, promoting the chelation of many elements and making these available to plant.
Humate as product derived from oxidized lignite, coal like substances associated with lignite out crop. (Stevenson.2002).Humate marketed for agriculture purposes may be soluble or insoluble and may be fortified with commercial fertilizer.
Humate contain between 30 and 60 percent humic acid. humate contain very little fulvic acid and biologically imp. Material such as protein and polysaccharides.
Humentos: It is a K-humate extracted from brown coal. Potassium humate is the salt of humic acid. Potassium humate is dark coloured, water soluble but alkali insoluble.
It is liquid product that is easy to apply on the soil e.g.as a fertilizer additive or as foliar treatment. It has been successfully applied in agriculture, horticulture; landscaping and cultivation.
The treatment of potassium humate is stimulatory for nutrients uptake of Glycine max Phaseolus mungo and Triticum aestivum.
Compost (commercial or "home-grown"): It is made from decayed organic materials such as straw, corn cobs, food wastes, cocoa bean hulls, poultry litter, grass clippings, leaves, and manure. Composts improve soil structure and slowly release nutrients to plant roots.
They return to the earth to supply nutrients for the next cycle of seeds.Compost 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.
Mushroom compost: It is used or “spent” compost from mushroom farming. It is some combination of manures, wheat straw, corn cobs, feather meal, peanut meal, peat moss, lime, etc. Mushrooms grown in this media use only a small portion of the many nutrients.
Nutrient analysis: 2.75-1.5-1.5. Can have high soluble salt levels and should be fully incorporated and watered prior to planting.
Peat moss: It is partially composted moss mined from prehistoric non-renewable bogs. Light and porous, it absorbs 10-20 times its weight in water. Its high surface tension causes it to repel water when it’s dry, so do not use as mulch or top-dressing.
Contains little nutrient value, but has a high nutrient-holding capacity. Acidic (as low as 3.0 pH); good for working into azalea and blueberry beds.
LeafGro: It is composted leaves and yard debris. Approximate analysis 1-.5 -1, with a pH range of 6.8-7.2. Holds 225% of its weight in water and does not repel water when dry as peat moss does. Use as a soil amendment, mulch, potting mix component, or top-dressing when seeding turf. Good peat moss substitute.
Green manure: It 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.
Stimulates the activity of soil micro-organisms. The ability to bind contaminants is exhibited when using organic soil mulches. Green manuring crops act as cover crop.
Crop Residues: Leaves make dark, rich compost that add nutrients to soil and help keep our plants strong and disease free. Fall cleanup is a great time to start a compost pile and put those leaves to work.
Other organic fertilizers: Include FYM, Vermicomposting, bird and bat droppings, blood meal, bone meal, and fish meal cattle manure. 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.
Inorganic soil conditioners:
Synthetic Binding Agents: New polymers applied at much lower rates have been promoted as soil conditioners e.g. Natural polysaccharides, Anionic Cationic polymers, polyacrylamides, Ammonium alkyl ether sulphate.
Characteristic of Synthetic Binding Agents: The compounds are very high molecular weight, long-chain polymeric, organic compounds, which bind soil particles and form stable aggregates.
Gelforming polymers: Gelforming polymers or insoluble water absorbing polymers was first introduced for agricultural use in the early 1980’s. Great water absorbing properties.Amount of cross linker influenced a mechanical properties of hydrogels.Reduce waterstress of plants Hydro gels are also claimed to reduce fertilizer leaching.
Polyacrylamide: Polymeric soil conditioners were known since the 1950s. These polymers were developed to improve the physical properties of soil in view of: Reduce ssurface sealing, Increase seedling emergence, Reduce runoff and erosion, Reduce fertilizer and pesticides losses. It is a synthetic binding agent which can be use in investigating physical quality of coarse - textured soil is often poor due to high % of macrospores.
Other minerals conditioners: Limestone, crushed rock and other high in calcium or magnesium will improve the physical condition of some soils when applied at several tons per acr.
Other inorganic compound , which contain small amount of a wide variety of essential and non-essential elements , applied at low rate have been promoted as soil conditioners. Most of these product at the rates recommended will not supply enough Ca and Mg to change the cation compositions of soil component.
“MK” as a soil conditioner is a by-product from concrete manufacturing. The components of MK are Ca compound and hydro-silicate compound about 60-70% other compound such as Si, Al and anhydrous silica.
It’s EC – 2.1 ds/m, CEC – 25 cmol/kg and pH – 10.2.MK application had been found effective on silicon uptake in rice crop, increase shoot dry matter and grain yield as compare to control.
fly-ash having both the soil amending and nutrient-enriching properties is helpful in improving crop growth and yield in low fertility soils. Particle size from 0.01 to 100 µm, low bulk density, high surface area and light texture.
It has been shown that FA based soil conditioner not only improves the crop productivity and soil fertility but also mobilizes macro and micronutrients in the soil . Fly ash was securely collected from the hopper of thermal power plant and was magnetized to produce novel soil conditioner Biosil.
The change in EC indicates positive impact of Biosil application to the soil under one cycle of cropping.
ALKYL ETHER SULPHATE:
These compounds are known as “Soil wetting Agent”. Another category of soil conditioners includes microorganisms and activators (Bama et al., 2004).
Rakesh Giri Goswami1* and Ashish Kumar Singh1
1Ph.D. Scholar Department of Soil Science and Agricultural Chemistry
Indira Gandhi Agricultural University, Raipur -492012 (C.G), INDIA