After having destroyed soil fertility from excessive and continuous application of chemical fertilisers, agricultural scientists are now telling you to kill the remaining 'life' in your soils by drenching the crop fields with chemical herbicides. Funds from the Rashtriya Krishi Vikas Yojna are being used to promote 'zero tillage' across the country, a flawed technology that is being pushed at the behest of the pesticide companies.
This suggestion comes at a time when remote sensing data collected by NASA satellites have confirmed that the growth rate of foodgrain production in India has been stagnant in the last decade.
The other day, a news report " 'Zero tillage' method to save labour and water" (Hindustan Times, June 26, 2010) caught my eyes. This is how it began: "Now, Indian farmers can grow paddy within days of harvesting their wheat crops -- and that too without ploughing the field." The Lucknow dated news report quoted scientists at the CSA University of Agriculture and Technology in Kanpur. Following successful field trials in three blocks of Kanpur Dehat in Uttar Pradesh, the new technique has gone 'live' in three districts of central Uttar Pradesh -- Kanpur, Kanpur Dehat and Kannauj.
'Zero tillage' is now being followed in over 100,000 hectares across the country. Although scientists are trying to create an hype by saying that 'zero tillage' increase yield, in reality it provides no significant improvement in yields. In several cases, the yields have come down. Also, it provides no reduction in the cost of cultivation. With new equipments and more herbicides, the cost remains in the same bracket.
Now, before I move ahead, it is important to examine the first para of the news report. It effectively means that 'zero tillage' enables farmers to undertake sowing of paddy within days of harvesting wheat. But I wonder, why do farmers need to sow paddy within days of harvesting wheat? There is a gap of about one and a half month to two months in the harvest of wheat and the transplanting of paddy in the northern belt of the country. Wheat is harvested in the last week of March or in the first week of April, and the transplanting of paddy takes place after the onset of monsoon rains in the month of July.
Aren't scientists therefore deceiving farmers (and of course the policy makers so that they can allocate funds) in order to justify the need for this new technology?
Now read this: "Zero tillage means there is no activity on field, the moisture level present in soil is maintained. seeds of new crops germinate with the help of the ambient moisture in the soil," says Dr V P N Singh, research director of the Rashtriya Krishi Vikas Yojna at CSA University. The catch lies here: "We have selected a new weedicide known as sulpho-sulphura. It will be sprinkled on the land along with other weedicides to remove weeds completely." Which are the other weedicides? Roundup Ready of Monsanto, Isoproturon etc.
Zero tillage is also being promoted in the name of conservation agriculture [I draw your attention to my article: New language, Old crisis http://www.indiatogether.org/2009/mar/dsh-sustag.htm]
I had written that conservation agriculture is about no tillage. It is based on minimal soil disturbance, organic residue retention and crop rotations. It is believed that the shift to zero tillage or minimal tillage will not disturb the soil, and therefore help in conserving natural resources. I've always thought earthworms were nature's tillers, so it's not clear to me exactly what zero tillage would amount to, since the earthworms would go on tilling anyway, unmindful of new agricultural terminology. Bhaskar Save tells us that earthworms turn around 6 tonnes of soil in its short lifespan. Zero tillage sounds unfamiliar in the Indian context!
Zero tillage has brought about its own industry. And that is what primarily interests agricultural scientists. Among the new conservation technologies required are: Laser land levellers, which have thus far been imported, but some of whose parts are now being fabricated locally; Zero till planters, including the second generation 'Happy Seeders' and 'Turbo Seeders;' Rotatory Disc Drills used for intensive soil working; and of course a range of herbicides.
All this equipment has been suitably modified and redesigned. Among the planter prototypes, you now have the multifunctional-multicrop-ferti-seed-zero till/raised bed planters. Don't bother trying to understand its multifunctional operations; there are already 150 fabricators and entrepreneurs breathing down our necks pitching the device. Which makes me wonder why agriculture scientists never think beyond costly equipment and endless chemicals. Why do they have to rely on imported concepts of sustainability, and the technology options linked to those ideas? Why can't they look inwards, search for the wonderful low-external-input technologies that local farmers have perfected over the years?
The answer is that they are actually not working for farmers anymore. Farmers just happen to be incidental, coming in handy to promote the machines, chemicals and the hybrid/GM seeds. If only they had listened to farmers, spent more time understanding and then improving sustainable farming systems, the face of Indian agriculture would have been ever-smiling. Farmers have all the answers, and they in fact it is they who need to show us the way towards sustainable agriculture, wherein the natural resource base remains protected and preserved.
To those who think 'Zero tillage' helps in carbon sequestration, here is my response http://devinder-sharma.blogspot.com/2010/03/does-zero-tillage-help-in-carbon.html
Showing posts with label zero-tillage. Show all posts
Showing posts with label zero-tillage. Show all posts
Does 'zero-tillage' help in carbon sequestration?
Some 25 years back or may be still more, I remember the first time I reported about 'zero tillage' (at that time I worked with the Indian Express). The news report I wrote was based on a study conducted by Punjab Agricultural University, Ludhiana, on 'zero-tillage' in maize. The PAU study ofcourse was all ga-ga over the virtues of no-tillage.
I wasn't convinced then, nor am I now. Although the World Bank supported Conservation Agriculture talks profusely about the merits of 'no-tillage', and the subject has assumed importance in the ongoing debate on climate change, I would rather ignore the suggestion than to add onto the existing agrarian crisis. But then, knowing that Indian scientists only replicate what American universities experiment with, I am sure they will try to push 'zero-tillage' to the unsuspecting farmers in the days to come.
However, I always wonder how can scientists talk of 'zero-tillage' in Indian agriculture when nature had bestowed us with the best tiller we know -- the lowly earthworm. Each earthworm in its lifespan upturns some 6 tonnes of soil, and therefore is called nature's tiller. If this wasn't useful, I am sure earthworms would have disappeared from the tropical soils much before chemical fertilisers decimated its numbers.
The Soil Association (in UK) had recently come out with a report, entitled: 'Soil Carbon and Organic Farming', which made the following two points:
Ploughing: A concern that the common use of deep cultivation in organic farming could be a weakness are answered by a number of trials in Europe that show that the depth of cultivation has no effect on the overall soil carbon levels of organic farming. Ploughing is used to incorporate organic matter into the soil; with sufficient inputs, increases in ploughing depth can even increase topsoil depth.
'Min-till’ and ‘no-till’: Reduced soil cultivation is the main non-organic farming solution commonly put forward for raising soil carbon levels, but its benefits have greatly been exaggerated. According to government scientific advice, the soil carbon benefits are minimal in the UK. Reduced tillage is effective in maintaining soil carbon storage in semi-arid regions where carbon is being lost by erosion and by the use of fallow periods, but otherwise there is no clear scientific evidence that it increases carbon levels over the whole soil profile, and certainly not to the extent of organic farming. Moreover, the carbon is then in a relatively unstable form, and any soil carbon gains may be offset by higher soil N20 emissions.
The report says very conclusively that there is no scientific evidence of enhanced carbon levels from 'zero-tillage' or 'no-tillage.' And yet, ICAR scientists (and also from ICRISAT and other international agricultural research centres) are swarming into the villages to draw farmers into practicing 'zero-tillage', and like what they did to establish the gains of Green Revolution technologies, they are hyping the results to show how effective 'no-tillage' is as a Conservation Agriculture technology.
What they are ofcourse not telling is how does (and how much) the promotion of 'no-tillage' helps in the sale of herbicides and some related farm equipments.
Meanwhile, Doug Gurian-Sherman and his colleagues in the Union of Concerned Scientists, Washington DC, have come out a two-page fact sheet on Agricultural Practices and Carbon Sequestration (published Oct 1, 2009). They have clearly established that a number of biological and soil-based integrated systems have a greater potential to sequester carbon. I am reproducing below some relevant sections from the fact sheet:
One of agriculture’s major opportunities to help mitigate the effects of climate-warming gases lies in management of soil to increase organic content, thereby removing carbon from the atmosphere. Many scientists are conducting studiesto determine which agricultural practices will in fact sequester carbon. Recent studies, summarized below, demonstrate that a number of biological, soil-based practices employed in integrated systems have great potential to sequester carbon. In contrast, recent studies suggest that no-till, a form of conservation tillage, has environmental benefits such asreducing soil erosion, but may not sequester more carbon than conventional tillage (plowing).
Integrated soil-based practices The most promising systems for carbon sequestration in soil combine crop rotation and low or no inputs of pesticides,herbicides, and industrial fertilizers. Long-term studies done by the Rodale Institute and others suggest that such systems build (not simply conserve) significant quantities of soil organic carbon through a variety of mechanisms such as enhanced abundance of mycorrhizal fungi. Several studies, including some done over long periods of time, have compared carbon accumulation in organic (plowed) and conventional (plowed) systems and demonstrate that organic systems sequester more carbon than conventional chemical-intensive systems.
In a head-to-head comparison between conventional no-till and organic plowed systems, organic plowed systems sequestered more carbon even though the sampling was restricted to shallow soil, where no-till tends to show carbon accumulation.
Although more studies are needed, there are good reasons to believe that organic systems would do atleast as well as conventional systems deeper in the soil. Current organic systems typically employ plowing to control weeds, and conventional plowed systems generally sequester more carbon at greater soil depths than no-till. Systems that use crop rotations and green and animal manure have shown higher biodiversity by foregoing chemical pesticides, supplying more diverse habitats, and reducing nitrogen pollution. Systems that integrate livestock and crops, employ perennial pastures, and adopt many of the practices used in organic production (e.g., long crop rotations, leguminous crops and cover crops, manure produced by livestock as fertilizer) also have shown potential for improved greenhouse gas balance, reduced pollution, and higher profitability.
Further research on these promising approaches will help optimize their benefits and determine their applicability across geographic regions. In summary, available data suggest that organic and near-organic farming systems achieve greater carbon sequestration and other benefits compared with conventional systems. Further work, supported by adequate research funding, is needed to realize the promise of these biologically sophisticated production systems.
Summary of the science The current scientific literature does not support favoring no-till over plowing for carbon sequestration. The emerging consensus from numerous studies and reviews is that under a variety of environmental conditions no-till sequesters nomore carbon than plowing. The apparent advantage for no-till in previous studies of carbon sequestration was an artifact of sampling carbon only near the soil surface.
I wasn't convinced then, nor am I now. Although the World Bank supported Conservation Agriculture talks profusely about the merits of 'no-tillage', and the subject has assumed importance in the ongoing debate on climate change, I would rather ignore the suggestion than to add onto the existing agrarian crisis. But then, knowing that Indian scientists only replicate what American universities experiment with, I am sure they will try to push 'zero-tillage' to the unsuspecting farmers in the days to come.
However, I always wonder how can scientists talk of 'zero-tillage' in Indian agriculture when nature had bestowed us with the best tiller we know -- the lowly earthworm. Each earthworm in its lifespan upturns some 6 tonnes of soil, and therefore is called nature's tiller. If this wasn't useful, I am sure earthworms would have disappeared from the tropical soils much before chemical fertilisers decimated its numbers.
The Soil Association (in UK) had recently come out with a report, entitled: 'Soil Carbon and Organic Farming', which made the following two points:
Ploughing: A concern that the common use of deep cultivation in organic farming could be a weakness are answered by a number of trials in Europe that show that the depth of cultivation has no effect on the overall soil carbon levels of organic farming. Ploughing is used to incorporate organic matter into the soil; with sufficient inputs, increases in ploughing depth can even increase topsoil depth.
'Min-till’ and ‘no-till’: Reduced soil cultivation is the main non-organic farming solution commonly put forward for raising soil carbon levels, but its benefits have greatly been exaggerated. According to government scientific advice, the soil carbon benefits are minimal in the UK. Reduced tillage is effective in maintaining soil carbon storage in semi-arid regions where carbon is being lost by erosion and by the use of fallow periods, but otherwise there is no clear scientific evidence that it increases carbon levels over the whole soil profile, and certainly not to the extent of organic farming. Moreover, the carbon is then in a relatively unstable form, and any soil carbon gains may be offset by higher soil N20 emissions.
The report says very conclusively that there is no scientific evidence of enhanced carbon levels from 'zero-tillage' or 'no-tillage.' And yet, ICAR scientists (and also from ICRISAT and other international agricultural research centres) are swarming into the villages to draw farmers into practicing 'zero-tillage', and like what they did to establish the gains of Green Revolution technologies, they are hyping the results to show how effective 'no-tillage' is as a Conservation Agriculture technology.
What they are ofcourse not telling is how does (and how much) the promotion of 'no-tillage' helps in the sale of herbicides and some related farm equipments.
Meanwhile, Doug Gurian-Sherman and his colleagues in the Union of Concerned Scientists, Washington DC, have come out a two-page fact sheet on Agricultural Practices and Carbon Sequestration (published Oct 1, 2009). They have clearly established that a number of biological and soil-based integrated systems have a greater potential to sequester carbon. I am reproducing below some relevant sections from the fact sheet:
One of agriculture’s major opportunities to help mitigate the effects of climate-warming gases lies in management of soil to increase organic content, thereby removing carbon from the atmosphere. Many scientists are conducting studiesto determine which agricultural practices will in fact sequester carbon. Recent studies, summarized below, demonstrate that a number of biological, soil-based practices employed in integrated systems have great potential to sequester carbon. In contrast, recent studies suggest that no-till, a form of conservation tillage, has environmental benefits such asreducing soil erosion, but may not sequester more carbon than conventional tillage (plowing).
Integrated soil-based practices The most promising systems for carbon sequestration in soil combine crop rotation and low or no inputs of pesticides,herbicides, and industrial fertilizers. Long-term studies done by the Rodale Institute and others suggest that such systems build (not simply conserve) significant quantities of soil organic carbon through a variety of mechanisms such as enhanced abundance of mycorrhizal fungi. Several studies, including some done over long periods of time, have compared carbon accumulation in organic (plowed) and conventional (plowed) systems and demonstrate that organic systems sequester more carbon than conventional chemical-intensive systems.
In a head-to-head comparison between conventional no-till and organic plowed systems, organic plowed systems sequestered more carbon even though the sampling was restricted to shallow soil, where no-till tends to show carbon accumulation.
Although more studies are needed, there are good reasons to believe that organic systems would do atleast as well as conventional systems deeper in the soil. Current organic systems typically employ plowing to control weeds, and conventional plowed systems generally sequester more carbon at greater soil depths than no-till. Systems that use crop rotations and green and animal manure have shown higher biodiversity by foregoing chemical pesticides, supplying more diverse habitats, and reducing nitrogen pollution. Systems that integrate livestock and crops, employ perennial pastures, and adopt many of the practices used in organic production (e.g., long crop rotations, leguminous crops and cover crops, manure produced by livestock as fertilizer) also have shown potential for improved greenhouse gas balance, reduced pollution, and higher profitability.
Further research on these promising approaches will help optimize their benefits and determine their applicability across geographic regions. In summary, available data suggest that organic and near-organic farming systems achieve greater carbon sequestration and other benefits compared with conventional systems. Further work, supported by adequate research funding, is needed to realize the promise of these biologically sophisticated production systems.
Summary of the science The current scientific literature does not support favoring no-till over plowing for carbon sequestration. The emerging consensus from numerous studies and reviews is that under a variety of environmental conditions no-till sequesters nomore carbon than plowing. The apparent advantage for no-till in previous studies of carbon sequestration was an artifact of sampling carbon only near the soil surface.
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