Types of conservation tillage are; mulch tillage, no-till farming, minimum tillage, ridge-till farming, and strip tillage.
This article discusses the types of conservation tillage and their characteristics, as follows;
1). Mulch Tillage (as one of the Types of Conservation Tillage)
Mulch tillage or mulch-till is a type of conservation tillage whereby the soil is tilled mildly and plant biomass residue is left to cover the top layer of soil.
Tillage occurs in this method. However, in accordance with the principles of sustainable farming, efforts are made to ensure that this tillage does not disrupt soil equilibrium in terms of structure and composition.
In mulch tillage, tools like chisel plow, disks and blades are used to perform shallow tillage of the soil. The aim here is to create crevices where crops can be sown.
The soil is not stirred or inverted (known as ‘non-inversion’ tillage).
Plant biomass that is used as mulch may be derived from any of various routine processes like weed control, crop management and harvest. The residue from these processes is not discarded or used for waste-to-energy purposes, but is rather spread over the soil and allowed to accumulate over time.
To control weeds in this type of conservation tillage, herbicides are often used .
Mulch tillage is useful for mitigating soil erosion and improving soil organic content, structural resilience and fertility.
The implementation of this method is beneficial across a broad range of conditions. However, it is particularly suitable for soils in regions where natural hazards like flooding, and other issues including erosion, slope instability, and desertification are a threat to agricultural productivity.
2). No-Till Farming
No-till farming (also called ‘no tillage’ or ‘zero-till’) is a type of conservation tillage that involves efforts to reduce soil disturbance to the barest minimum at all stages of crop production including planting and harvest .
In no-till farming, seed planting is done in shallow seedbed, crevices or furrows that are created in soil using row chisels, agricultural drills, disk openers, row cleaners or coulters.
After seed planting, crop residue may be used to cover and seal that shallow seedbeds.
No-till farming is most effective when combined with mulching and other sustainable practices. It is also very suitable for sensitive agricultural soils, in regions where environmental problems like climate change and drought-risk, affect the soil.
The concept of no-till may be misunderstood because of its name. Tillage of the soil is not completely omitted since this is necessary for seed planting. Rather, soil tillage and all other forms of disturbance are reduced as much as possible, such that only a shallow portion of the topsoil is rifted for planting.
Like mulch tillage, the soil is not inverted or stirred in no-till farming. This enables the basic advantages of conservation tillage such as carbon capture and sequestration, and erosion-mitigation, to be achieved.
3). Minimum Tillage (as one of the Types of Conservation Tillage)
Minimum tillage (also called ‘reduced tillage’ or ‘minimum-till’) is a type of conservation tillage that is characterized by less soil disturbance or furrowing than conventional tillage practices .
As the name implies, minimum tillage is a slight deviation from conventional tillage system, as it does not aim to completely eradicate soil disturbance, but to minimize it .
The approach to minimum tillage may vary significantly from one region to another. This is because of the need to make adjustments based on existing conditions.
For example, in cases where crop residue is not abundant, minimum tillage may exclude residue accumulation or mulching. This could be replaced with fertilizer application, composting, and plastic mulching, among others.
Herbicides are also commonly used to control weeds in this method.
4). Ridge Till Farming
Ridge till (also ‘ridge-till’ or ‘ridge tillage’), is a type of conservation tillage whereby permanent ridges are used for planting, with minimal soil disturbance during both planting and harvest periods.
Any of various equipment can be used in this method, including; row cleaners, coulters and disk openers.
The goal here is to reduce the mechanical alteration of the soil and prevent digging or stirring, by using shallow seed beds in the ridges, for planting.
Ridge till is good for cash crops including grains like corn, and legumes like soybeans.
5). Strip Tillage (as one of the Types of Conservation Tillage)
Strip tillage (also known as ‘zonal tillage’) is a type of conservation tillage that separates agricultural land into narrow, tilled strips that alternate with no-till zones .
The strip till method is one of the most multifaceted types of conservation tillage, as it shares attributes with other types like no-till and minimum tillage systems.
Regions between the tilled strips are left undisturbed, in order to optimize soil characteristics in such regions.
Strip till is an efficient method of soil management and crop cultivation in regions with hard, adhesive soils. It is also good for regions with excessively-wet soils that have high moisture content.
Fertilizer application and crop residue may both be used in this type of conservation tillage.
Types of conservation tillage are;
1. Mulch Tillage
2. No-Till Farming
3. Minimum Tillage
4. Ridge Till Farming
5. Strip Tillage
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