In green revolution this NPK theory caused major loss in soil fertility and ultimately the agriculture productivity/unit fertiliser use has gone down in most of the green revolution areas. I am taking example of India where the production enhanced due to vertical and horizontal spread in irrigation facility and yes, NPK fertilisers caused sudden jump in production in the initial 15-20(because of inherent fertility of land- no micro nutrient deficiency ) years, at the cost of soil health and water productivity .However, it has been experienced during last two decades (1990s onward) that there is minimal increase in productivity despite increase in graph of fertiliser use. On the other side in drylands (60% part of agriculture) where fertilisers use is minimum and more use of organic inputs, the productivity in the good rainfall years surpasses the conventional system, and the yield of conventional system (clearly visible in cotton) in the poor rainfall years is much below than organic system. There may be some other reasons for emphasising the NPK use rather than the agro-ecological need. Also application of NPK fertilisers there is possibility of risk addition in the agriculture production in the changing climate scenario.
May be optimum use of water integrate with organic manure application is the key of sustainable agriculture in long term.
I think irrigation facility and prudent water use is more important to sustainable agriculture especially under arid ecosystems.
Obviously water is more important input than fertilizer. But, as you have explained, clearly integration of water use with fertilizer application would give higher use efficiency for all the inputs.
In my opinion, water is more important. New fertilizers and techniques for use reduced environmental damage. Just take a look in "fertigation".
Both of these are indispensable for sustainable agriculture.However availability of water and or irrigation facilty is of prime reason.Only then comes role of fertilizer. Simply one thing is very clear that without water their is no significance of fertilizer. This is the reason why fertilizer use efficiencies are always higher under irrigated conditions rather than arid or dry agricultural systems.However converse is not true.One can go for at least some yield without fertilizer but without water no growth is sustainable. Hence my opinion is that water is at number 1 and fertilizer is at number 2.However optimal combination of both of these factors has potential to give synergistic effect in most of the agrarian systems.
Thanks to all the researchers who replied and expressed that water is more important BUT my question is more related to the use of Chemical fertilisers Vs organic manure, still seeing the reality of fertilisers most of the subsidy is being given to fertilisers and least concern to the organic manure or recycling of organic resources that may help in real sustainability.
Dr. Sharma, definitely organic fertilizers are important components but to use it efficiently you need water to recycle it. So without available water you can not do anything. That,s why water is most important component for sustainable agriculture.
Man-made NPK in place of OM (organic matter) is highly correlated to a reduction in water holding capacity in soil. It is far better to conserve than to find alternate sources. If organic matter is increased, irrigation can be reduced, since the water will hold onto the soil better, and healthier soil will increase the health of plants through symbiotic relationships with mycorrhizal relationships. In addition, reducing synthetic fertilizers will also protect water quality and reduce possible run-off issues. This is a highly complex issue, and one that needs a multi-faceted approach.
Dear,
Water is more important so as the fertilizers. the effect on plants is synchronize. Water is the medium for transporting nutrients to plant roots. So plants can not survive without water and production up to desired limit is only possible with proper nutrient availability.
Irrigation and fertility management are important components for sustainable agricultural productivity. Water is essential for plant temperature regulation, medium for soil nutrients transportation and important to enhance growth.
in my opinion, water (irrigation) and nutrients are both important for successful crop production and sustainable agriculture. i think we need to focus on the quality of irrigation water as well as focus on the nutrients such as NPK but also micro nutrients. Most of the studies are devoted to NPK, but micro nutrients and other essentials are either ignored or less focused. We also need to develop crop specific nutrient management technologies, and make awareness about soil testing before cultivation for intended crops to be grwon.
May be I failed to convey the real query that synthetic fertilisers are being promoted as panacea for high production ,however this has been disproved if we think for long term sustainability. In this process the role of organic manure has been almost neglected. The results are degrading soil health and water holding capacity and decreasing productivity . And the reality is if we combine both prudent water management and organic manure then it will be ecologically and economically viable approach. Fertilisers may have least role in long term sustainability. now question may be clear for long term sustainability i.e. which combination is better 1. water with synthetic fertilisers 2. water with organic manure . I would request please send your comments on this line.
Definitely water with organic manure is long term sustainable approach. Organic manure with available water emphasizes on development of integrated, environmentally-safe and ecologically-sustainable agricultural production system in which maximum reliance is placed on locally available or farm produced renewable resources and the management of self regulating system which promotes and enhances agro-ecosystem health including biodiversity, biological cycles and soil biological activity.
I absolutely agree with observation of Dr.Arun Sharma . But one question still remains unanswered - what would be production potential of sustainable organic agriculture in comparison to chemical agriculture.We were doing organic agriculture in India till early 1960s but facing acute food shortage then . Regards.
Dr, Tewari, organic agriculture in presence of sufficient water is the backbone to improve soil quality. If soil quality is improved, we shall simultaneously achieve the other goals like food quality/safety, environmental quality and human/animal health as well. With the use of chemical fertilizer along with desirable water soil quality has been degraded as well as water and atmospheric resources. It is anticipated that the likely climate change and associated extreme climate events may degrade the land and soil resources in the years to come by way of influencing 1. soil temperature, 2, altered pattern of evaporation, 3. changes in soil moisture regime, 4. increased risk of soil erosion and salinisation, 5. changes in physical properties, 6. alterations to mineralisation and elemental recycling, 7. changes in soil organic matter status and emissions, 8. changes in activities and species diversity of soil fauna and 9. biomass productivity.
When we talk about sustainable production system, it must be on long term basis. To be the system a sustainable one our efforts must to reorient the inputs delivery in balanced way to match the crop need. Hence integrated approach in supplementing and complementing the inorganic and organic inputs along with provisioning crop per drop basis water concept is the need of hour to sustain the sustainability of crop production.
Dr. Tarfafdar , you are right , but still my point is not answered. Do we so much capable to leave the chemical agriculture and turn whole agriculture organic by way of advancement of science of organic farming .I am finding Dr. Binoy's observation more applicable in present context.Do we really know what would be country's agricultural production if we bring all cultivated land under organic agriculture . I understand your concerns regarding soil degradation , water quality deterioration , impact of climate change but I don't think that rapid replacement of chemical agriculture by 100% organic agriculture is possible because at the moment we are producing enough to feed our population , what would be scenario of country as a whole if we go for cent percent organic agriculture. Do any body have substantial understanding in this front ? Can we be able to maintain food grain production of 270 million tonnes , which we are producing at the moment by organic agriculture alone . Regards
Still in INDIA and other parts of world 60% area is dry land where chemical fertilisers did not show miracle due to lack of assured water. In these ares efficient use of rainwater combined with organic inputs can only be the solution for food security. On the other side millions of ha land in the irrigated areas loosing its productivity due to use of chemical fertilisers. Another wast area is under saline- alkali soils where use of chemical fertilisers only aggravated this problem . Now option remains only gradual increase of organic inputs use. Fortunately this organic inputs are available but either not properly used or misused as fuel/burned in the fields.
Good management practices of irrigation and fertilization is the best way for sustainable agriculture based on the conditions of the environment, soil situation, avialability of water and fertilizers. The integration between managment practices nd utilizing of resources should be considered.
Irrigation water and fertilizers are two principle factors in getting good crop production. In ample availabilty of irrigation water, nutrients in the form of NPK plays important role in plants nutirent acquisition however if soil have less orgnanic matter contents, nutirents retention is being affected and most of nutrients washed away (leaching and volatilization). So in my view, for sustainable agriculture, we should add organic manures to improve water hodling capacity of soil which in return also improves soil health and sustains its fertility. Application of green manure crops and organic matter are the key factors in achieving sustainable crop production along with the use of NPK.
There is no doubt that fertilizer is one of the essential key input for production and productivity of crops. Fertilizer alone contributes towards 50% of additional food production. Since there is no scope for extending the cultivable area, more productivity per unit area is the only option and fertilizer is the main cart puller. Further as the cost of fertilizer has increased many folds in recent times, alternate sources of nutrients should be included in the fertilizer schedule along with commercial fertilizers. The best management practices like balanced fertilization: integrated nutrient management involving fertilizers, locally available organics and biofertilizers: site specific nutrient management: customized fertilizers: and new modified or novel fertilizer product, for example nano-fertilizers, should be used in order to maximize nutrient use efficiency for sustainable crop production. There should be sufficient organic fertiliser in the system so that soil health and nutrient recycling can be maintained.
Here the query is what should be the future input organic or chemical. Giving the option of NANO particle is taking the discussion in another direction that is not the aim of this question. NANO is a part of synthetic inputs and its properties, effects on soil and environment are yet to be fully studied and TILL THEN it may not be promoted and it may be discussed with fertilisers.
Dr. Sharma, bio-synthesized nano-nutrients are not a synthetic input. It is helping/insisting plants to work their maximum potential to release enzymes to mobilize the nutrients from th as well as it also proved helping in enhancing. nutrient use efficiency in multiple folds. Therefore, you now cant ignore them.
Dr.Tarafdar though I admire organic agriculture but I have only one doubt - it's production potential.Bio synthesized nano nutrients are okay but what about their toxicity ? Do we know are that they absolutely non- toxic ?
Dr. Tiwari, if you use recommended doses as foliage mode then bio-synthesized nano-nutrients are proved to be non-toxic to soil microorganisms and animals. Logically also they are non-toxic as with time, it was found that they are becoming mega particle and absorbing by plant cells as nutrients.
NOW here the reply comes that dose and over dose . Can we have any control on dose of chemical fertilisers and pesticides that farmers apply and he keeps on increasing the dose of chemicals because of lost of soil fertility for or resistant in pest and same is true with your NANO. There is no control of chemical use by the farmers and it is linked with credit facility. While with organic inputs the dose decreases year by year as the soil and microbs starts producing and accumulating organic matter and also no credit facility available , so farmer never apply overdose- a self controlled system.
The stereotype apprehension shown by many of the researchers that who will feed the world ---the reply is same who will feed the world when whole land lost productivity with the use of fertilisers,pest become resistant, pollinators and defenders vanished and farmers become prone to debt and diseases.
I have been working for organic farming for more than a decade and found that there is no yield loss once the system developed , rather cost of production goes down and farmers become self reliance and get better price.
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