Conservation Tillage - Concept, Scope and Advantages

 

       Conservation Tillage

  Lakhan Patidar

           Soil erosion in India is widespread and a serious threat to survival, well-being and Agriculture. It has been estimated that an area of over 80 million hectares or about one-fourth of our total area is exposed to wind and water erosion out of which 40 million hectares of land has undergone serious erosion. Ironically the extent of soil erosion is increasing in spite of our efforts to check soil erosion. Experts have estimated that about 40,000 hectares of our land is permanently lost to cultivation and much larger area is rendered less productive every year due to wind and water erosion.

        Conservation tillage which advocates the maintenance of crop residue cover of 30% on the soil surface is soundly based sustainable agriculture. This system reduces the losses of soil and water a compared to conventional tillage system. Crop residues left over the soil surface reduces soil erosion and conserve soil moisture. Presence of crop residue increased weed suppression and did not result in an increase in herbicide application. The benefits of conservation tillage are reduces machinery wear, Improves soil tilth, Increases organic matter, soil biological diversity and traps soil moisture to improve water availability and water use efficiency.

Tillage is defined as the physical, chemical or biological soil manipulation to optimize condition for germination, seeding and root establishment for batter crop growth. It aims to create a soil environment favorable for the plant growth. Appropriate tillage practices are those that avoid the degradation of soil properties and maintain crop yields as ecosystem stability. Conservation tillage provides the best opportunity for halting degradation and improving for restoring and sol productivity.

In old concept of tillage maximum manipulation of soil creates some major problems like:

·       Soil compaction

·       Change in soil structure

·       More cost of cultivation

·       More soil erosion

 

These drawbacks of conventional tillage can be mitigated by the use of Conservation Tillage Practices. Some of the major advantages of conservation tillage are as follows:

Environmental Benefits:

·       Reduces soil erosion from both water and wind (90% erosion reduction can be expected when using a no-till instead of intensive tillage system).

·       Increases organic matter (each tillage trip oxidizes some organic matter; research shows continuous no-till can increase organic matter in the top 2 inches of soil about 0.1% each year).

·       Improves water quality (when combined with irrigation water management, crop nutrient management, integrated pest management, conservation crop rotation, in integrated system, conservation tillage plays an important role in improving both runoff to streams, rivers, and lakes as well as water that finds its way into aquifers).

·       Improves wildlife habitat (the crop’s residue provides food and shelter. In addition, if combined with other needed habitat, such as grassy cover and woody areas, wildlife may increase significantly).

·       Altering tillage practices changes weed seed depth in the soil, which plays a role in weed species shifts and affects the efficacy of control practices. Ineffective weed control is a major deterrent to the adoption of conservation tillage system, especially no-tillage.

·       Other benefits include reduced soil compaction, utilization of marginal land, some harvesting advantages, and conservation compliance.

Economical Benefits:

·       Yields are good, if not better, than reduced or intensive tillage system when managed properly.

·       Optimizes soil moisture (improved infiltration and increased organic matter are especially important on droughty soils and may help the crop through a persistent dry period. Tillage reduces available moisture).

·       It saves time and efforts of farmers.

·       Reduces fuel consumption (no-till can reduce fuel use by 3.5 gallons/acre compared to intensive tillage).

·       Reduces overall production costs.

·       Reduces machinery wear (less machinery means fewer pieces need to be replaced).

 

In the modern time of Agriculture, where farming is being dependent on Agro-chemicals and fertilizers, we greatly need to adopt such practices which can mitigate the harmful effect of chemicals and fertilizers and maintain good soil health for our next generations.

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Broad Bed and Furrow System (BBF) for Soybean in Madhya Pradesh

Broad Bed and Furrow System (BBF)

for Soybean in Madhya Pradesh

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Lakhan Patidar

Generate a good income from farming in Rainfed areas is not very easy. Fluctuations in timing of onset of monsoon, erratic rain distribution during the crop season, sudden occurrence of high intensity rain storms and absence of in-situ water harvesting systems are major constraints in crop production in these areas. Although the amount and timings of precipitation received by crop cannot be altered but proper management of its utilization can improve crop yields.

In irrigated farming, planting on flat lands and flood irrigation are commonly used practices. Main problems associated with such practices include higher input use (such as irrigation water, fertilizer, manpower etc.), declining water table because of over exploitation of ground water resources for irrigation, greater downward movement of water fertilizer and pesticide below root zone. Higher pest incidence and poor control of weeds and diseases. Thus in irrigated farming also, although intensive agriculture has brought substantial enhancement in production of food grains but it has threatened the environment safety and promoted' the degradation and inefficient use of basic resources such as land, water and fertilizer and also increased input cost which ultimately reduce the net income of farmers. Hence there is a need to manage both rain and irrigation water efficiently by adopting appropriate soil management technology.

Broad Bed and Furrow System (BBF)

The Broad Bed and Furrow system has been mainly developed at the International Crops Research Institute for the Semi-arid Tropics (ICRISAT) in India.

It is a modern version of the very old concept of encouraging controlled surface drainage by forming the soil surface into beds. The recommended ICRISAT system consists of broad beds about 100 cm wide separated by sunken furrows about 50 cm wide. The preferred slope along the furrow is between 0.4 and 0.8 percent on vertisols. Two, three, or four rows of crop can be grown on the broad bed, and the bed width and crop geometry can be varied to suit the cultivation and planting equipment.

In India the system has been used mainly on deep vertisols (heavy black clay soils sometimes called cotton soils), wide beds are used on a gentle grade and they are formed by ox-drawn wheeled tool carriers. 

Fig: Making of Broad Bed and Furrow.

The BBF system of sowing has the following objectives:

•     To encourage moisture storage in the soil profile. Deep vertisols may have soil moisture storage up to 250 mm, which is sufficient to support plants through mid-season or late-season spells of drought. The possibility is also increased of double cropping by means of inter-cropping or sequential cropping. The large water storage capacity of the soil supports growth more easily during the subsequent dry but cooler post-rainy season.
•    To dispose safely of surplus surface run-off without causing erosion from furrows.
•   To provide a better drained and more easily cultivated soil in the beds. There is only a narrow range of moisture conditions during which the soil can be efficiently tilled or planted, and timeliness is a key factor. Only about 20 percent of the deep vertisols in India are cropped during the rains, mainly because of poor workability when wet. If a crop can be established during the early rains, the profile is usually near saturation only for short periods during the latter half of the season, water is more efficiently utilized, and there is less need for run-off collection and storage.

IV.          The possibility of the re-use of run-off stored in small tanks. Small amounts of life-saving irrigation applications can be very effective in dry spells during the rains, particularly on soils with lower storage capacity than the deep vertisols.

Some other advantages of BBF planting method:

• Increase in water use efficiency
• Increase in crop productivity (5-10%)
• Less moisture stress during non- rainy days
• Time saving (25-30%) in irrigation
• Requires 20-25% lower seed rate
• Water saving up to 25-30%
• Better weed management
• Reduces crop lodging

The BBF system is particularly suitable for the vertisols. The technique works best on deep black soils in areas with dependable rainfall averaging 750 mm or more. It has not been as productive in areas of less dependable rainfall, or on alfisols or shallower black soils - although in the latter cases more productivity is achieved than with traditional farming methods. Other methods, with more emphasis on storage and irrigation within a package which includes BBF, are more likely to be viable for the alfisols.

An important component of the system is an ox-drawn wheeled tool bar, which can be used with ridgers to form the raised bed and also later for carrying precision seeders or planters. The tool carrier is thus used for the initial forming of the beds, the subsequent annual reshaping, and for all tillage, planting, and inter-row cultivation.

Fig: Structure of a sample Broad Bed and Furrow seed drill.

A raised land configuration ‘Broad Bed Furrow’ (BBF) system helps the soil to preserve the water level for a longer period. Holding moisture intact, the bed stimulates crop’s growth. This system would not only help in water conservation for better crop yield but also help adapt to the ever changing climate. The crops will respond better to fickle rain duration's and survive longer.