Climate resilient agricultural system – the way ahead

Dr Chinmoy Kumar Sarma

(drcksarma@gmail.com)

One of the critical challenges for a country's food security is climate change and its impact in the form of extreme weather events. The impact of climate change on agriculture is going to be one of the major deciding factors that will influence the food security of mankind in future. Noted agricultural scientist MS Swaminathan once added that climate change has a different meaning for different parts of the globe. Canada may benefit as the rise in temperature will allow them to grow more crops, but it would have the opposite effect here in India. It has been predicted that people, particularly those in developing countries, will face changes in rainfall patterns that will contribute to severe water shortages or flooding, a rising temperature that will cause shifts in crop growing seasons. Developing countries like India are more in danger because of the agrarian-based economy, excessive pressure on natural resources and poor coping mechanisms. An economic survey in 2017-18 cautioned that "climate change might be reducing annual agriculture income in the range of 15 per cent to 18 per cent and up to 20 per cent to 25 per cent for unirrigated areas". This creates food shortages, nutrient deficiencies in humans due to inadequate intake of healthy food makes humans vulnerable to health issues. Sustaining agricultural productivity is critical in the context of climate change for ensuring food and nutritional security for all.

Assam is extremely vulnerable to climate change as the state has a high reliance on agriculture that is likely to only increase because of its growing population. It is being realized gradually that there is a strong need to build resilient agricultural systems that have a high capacity to adapt to stress and changes and can absorb disturbances. Flood is not a new phenomenon in Assam and is characterized by its extremely large magnitude, high frequency and extensive devastation. Every year nearly 5 lakh hectares area is inundated by flood in the state. Rice is the most important crop of Assam and flood is the major production constraint affecting Kharif rice during June– September and crop loss may go up to 100% depending upon the duration of submergence. Crop planning through a selection of suitable crops and varieties as well as by adopting proper management practices is most urgently required in flood-affected areas of the state. Delayed sowing/transplanting of traditional course grain late Sali rice varieties with higher seedling age after the recession of floodwater are some coping strategies adopted by farmers under adverse situations up to the 1st week of September. Assam Agricultural University has developed submergence tolerant, staggered planting and short duration high yielding rice varieties for aberrant weather conditions. Submergence tolerant rice varieties like 'Ranjit sub 1', 'Bahadur sub 1' may be alternatives in chronically as well as occasionally flood-affected areas while staggered planting rice varieties like 'Gitesh' perform better where transplanting of seedling in time is difficult due to flood or drought. Some very short duration rice varieties (100 days) can also be tried during the post-flood situation with young seedlings up to 1st week of September after the recession of floodwater if the rice crop is damaged by a flood during August. Direct seeding of sprouted seeds of short duration varieties in puddle soil is another option up to the 1st week of September if seedling raising is not possible. In chronically flood-affected areas, rice seedling raising in upland areas at the community level is needed to address the seedling need at the village level during the post-flood situation. Similarly, early maturing and drought-tolerant cultivars can be options for drought-like situations. Seed shortage of suitable crop varieties is an important limitation faced by farmers to implement contingency crop plans to tackle aberrant rainfall situations. In vulnerable areas, farmers tend to dispose-off the entire product as grain and therefore depend on external sources for seed supply in the next season. So, the varietal shift needs to be carefully promoted by encouraging village level seed production to combat seed shortage.

Building resilience in the soil is vital for crop production under changing climate and soil health is the key property that determines resilience. Building up of soil organic carbon, controlling soil losses due to erosion and improving water holding capacity of soil enhance resilience in soil. Incorporation of crop residue into the soil instead of burning, the addition of organic matter through farmyard manure, composting, vermicomposting, green manuring etc., are important for improving organic carbon content in the soil. Balanced use of fertilizer, selection of the right type of fertilizer and improved methods of fertilizer application based on crop requirement as well as soil and weather condition are very much crucial for getting a good response from the applied nutrients. In Assam, Krishi Vigyan Kendras of Assam Agricultural University has initiated a programme to issue soil health cards every year to the farmers and the process is ongoing.

Various technologies based on a precision estimation of crop water needs and irrigation scheduling, adoption of scientific water conservation methods, altering the fertilizer and irrigation schedules, cultivating less water requiring varieties, adjusting the planting dates and adopting zero-tillage which may help farmers to reach satisfactory crop yields, even in deficit rainfall and warmer years. Water-smart technologies like rainwater harvesting and recycling, micro-irrigation, greenhouse, laser land levelling, reuse wastewater, deficit irrigation and drainage management can support farmers to decrease the effect of variations of climate.

Crop diversification is an important option for livelihood security and resilience to climate variability. Emphasis should be given to crop diversification and intensive crop production during the flood-free period, especially during the rabi season. Similarly, the practice of sole cropping or mono-cropping is predominant in the state but is risky and often results in low yields or sometimes even in crop failure due to erratic monsoon rainfall and uneven distribution. In such areas, intercropping or mixed cropping is a feasible option to minimize risk in crop production, ensure reasonable returns at least from the intercrop and also improve soil fertility with a legume intercrop.

The livestock sector will demand a supply of quality feed and water, improved shelter for reducing heat or cold stress, preventive vaccination etc. Betterment of feeding systems as an adaptation measure can indirectly improve the efficiency of livestock production. Use of community lands for fodder production during droughts/floods, improved fodder/feed storage method, feed supplements, micronutrient use to enhance adaptation to heat stress, designing suitable housing etc., are some important interventions that need to be adopted by the farmers. In the livestock, sector, maintenance of fodder bank and its scientific preservation to supply fodder during critical periods need to be planned depending upon the situation.

Similarly, in the fishery sector, the major problems generally faced by the farmers during a flood is escaping of cultured fish and entry of predatory fish which can be restricted by placement of nylon net along the periphery of fish ponds and by renovating or by raising the height of dykes of ponds to the desired level. The top, inner and outer dykes of ponds as well as adjoining areas can be best utilized for horticulture crops to maximize farm income. Pond water can be used for irrigation and silt, which is high-quality manure, can be used for crops, vegetables and fruit-bearing plants. Similarly, residues of vegetables cultivated can be recycled into fishponds. Deterioration of water quality, change in turbidity of pond water and deposition of sand and silt are some major problems in the fishery sector often associated with the flood which need to be addressed with scientific knowledge. Another problem often seen in the farmers' field is the non-availability of a quality fish seed round the year and if a flood washes away fish ponds, farmers become unable to restock their ponds. Maintenance of a fish seed bank for restocking after a flood is an important intervention that enhances the resilience of the system.

The government of India has undertaken various schemes to ensure synergy and effective utilization of existing resources. Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) was launched in 2015 to address the issues of water resources and provide a permanent solution that envisages Per Drop More Crop, by promoting micro/drip irrigation for the conservation of maximum water. Paramparagat Krishi Vikas Yojana mission was executed to extensively leverage the adaptation of climate-smart practices and technologies in conjunction with the Indian Council of Agricultural Research and state governments of India. Pradhan Mantri Fasal Bima Yojana is an insurance scheme to provide insurance coverage and financial support to the farmers in the event of failure of any of the notified crops as a result of natural calamities, pests & diseases. Indian Council of Agricultural Research through its network research Institutes, state agriculture universities and all line departments are implementing agriculture contingency plans in about 650 districts of India towards climate change preparedness for the last seven years.