S.K. Chaudhari’s research while affiliated with Resource Management and other places

Considering the importance of identifying hotspots of climate change risk and vulnerability for adaptation planning, this paper conducted a district level climate change risk and vulnerability assessment for India as per the framework suggested by the IPCC’s Fifth Assessment Report. Climate change risk was assessed in terms of an aggregated index of exposure, vulnerability and hazard that were constructed by aggregating relevant indicators. Climate change projections obtained using CMIP-5 climate models for the scenario RCP 4.5 for the period 2020–49 were used to represent hazard. The study categorized 193 districts into ‘very high’ or ‘high’ vulnerability many of which are in the states of Arunachal Pradesh, Chhattisgarh, Jharkhand, Karnataka, Madhya Pradesh, Maharashtra, Odisha, Rajasthan, etc. One hundred and nine districts categorized as ‘very high’ risk are in the states of Bihar, Kerala, Odisha, Rajasthan, Uttar Pradesh, Uttarakhand, etc. and those categorized as ‘high’ risk districts are in Chhattisgarh, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan, Uttar Pradesh, etc. Adaptation planning and implementation may prioritize these districts with relatively higher risk and vulnerability and identify adaptation strategies based on the drivers of risk and vulnerability identified.

Rice fallow refers to rainfed rice-growing regions where vast stretches of land remain uncultivated by the farmers during post-rainy (winter) season. This practice is primarily due to several challenges, including insufficient irrigation infrastructure and resources, cultivation of long-duration rice varieties that are harvested late (MTU 7029, BPT 5204, traditional local varieties etc.), issues related to both insufficient and excessive soil moisture at crop establishment and socio-economic issues like poor resources availability, lack of awareness on the improved practices and stray cattle . (Fig. 1). Rapid depletion etc of soil moisture from early monsoon withdrawal and disturbances from free grazing of livestock and blue bulls further contribute to the decision to leave land fallow during winter. In India, nearly 11.7 m ha of rice fallow land follows a mono-cropping, predominantly found in the eastern part of the country (83%) covering Bihar, Chhattisgarh, Odisha, Assam, eastern Uttar Pradesh, Jharkhand and West Bengal. With the increasing demand for food due to enormous population growth, it is essential to intensify crop production in these areas. However, cultivating a second crop during winter in these areas at present has numerous challenges (biotic/abioticstresses) (NAAS, 2013). Addressing these issues is a critical task for all the stakeholders (scientists/ policymakers) to fully explore the unexplored rice fallow lands in eastern India.In rainfed, rice-based mono-cropping systems, small and marginal farmers often find themselves trapped in a cycle of poverty due to limited resources. Introducing a second crop after rice harvesting in eastern India's rice fallow lands offers a promising way to boost agricultural productivity. Selection of the appropriate rabi (winter) crops depends heavily on their ability to withstand stresses (biotic/abiotic). The issue of rice fallow has recently gained significant attention among the policymakers and researchers, leading to increased the public investment. However, ad-hoc investment in fallow intensification often fails to deliver sustainable and satisfactory outcomes due to the complex and multi-dimensional nature of the challenges involved, including biotic, abiotic, policy, and socio-economic factors. The present publication based on the works carried out over a decade will provide a crucial insight for different stakeholders (policymakers/planners), helping to shape the policies, develop programmes, create effective implementation strategies, and pinpoint areas with investment potential.

Agricultural productivity in semi-arid regions is constrained by soil and groundwater salinity. This study quantified the desalinization potential of cut-soiler-constructed preferential shallow sub-surface drainage (PSSD) and its impact on crop performance in saline agroecologies. The study was conducted at the Indian Council of Agricultural Research (ICAR)-Central Soil Salinity Research Institute, Karnal, India, from 2019-2021. The rice residue-filled PSSD was simulated manually (60 cm depth) in a split-split plot experiment with saline and normal soil under saline water irrigation (4, 8, and 12 dS m ⁻¹ ). Cut-soiler PSSD were constructed in the middle of the lysimeter using rice residue (equivalent to 6 Mg ha ⁻¹ ) as the filling material with an outlet to quantify salt and water outflow. Pearl millet [ Pennisetum glaucum L. (R. Br)], variety HHB-197, and mustard ( Brassica juncea L.), variety CS-58, were grown in the rainy ( Kharif ) and winter ( Rabi ) seasons, respectively. The soil salinity profile decreased by 23.3%-58.5% with cut-soiler PSSD in different soils. The decrease in salinity was associated with increased plant height, dry matter accumulation (DMA), net assimilation rate (NAR), crop growth rate (CGR), relative growth rate (RGR), leaf area (LA), and leaf area Index (LAI) in both crops. The pearl millet and mustard yield increases in the two soil types were 11.6%-43.3% and 26%-36%, respectively using saline water up to 12 dS m ⁻¹ . This study concludes that cut-soiler PSSD can effectively mitigate salinity stress and utilize saline water at the farm scale in salt-affected semi-arid agro-eco-regions.

Cotton (Gossypium hirsutum L.)—wheat (Triticum aestivum (L.) emend Fiori & Paol) cropping system with conservation agriculture (CA) practices is being recommended for diversification of the rice (Oryza sativa L.)—wheat (RW) system in South Asia including Indo-Gangetic Plains (IGP). But, long-term studies are limited on the impacts of CA-based management including nitrogen (N) fertilization for cotton–wheat (hereafter mentioned as CW) system to assess crop yield sustainability and soil health. Therefore, in this study of seven years (2013–14 to 2019–20), conventional tillage (CT) was compared with zero-till (ZT) permanent narrow (PNB), broad (PBB), and flat (PFB) beds with and without residue (R) and 100%N (in all treatments/plots) and 75%N (imposed only on residue-added plots after 3 years) in the alluvial soils of IGP. Mean cotton yield in ZT permanent broad (PBB100N + R) and flat (PFB100N + R) bed with residue and 100%N were higher by 52 and 53%, respectively, than with CT. The same permanent broad bed with residue but 75%N (PBB75N + R) increased 49% mean cotton yield than CT. Similarly, PBB100N + R, PFB100N + R, and PBB75N + R yielded more wheat by 16, 17, and 15%, respectively (P < 0.05) than CT. Again, PBB100N + R, PBB75N + R and PFB100N + R had significantly higher sustainable yield indices of cotton (30–33%), wheat (16–18%), and CW system (28–31%) than CT. PBB100N + R had 27.5% higher total organic carbon stock and 56% higher system water productivity and conserved highest 173.2 mm water annually compared to CT (P < 0.05). Notably, PBB75N + R could save 472.5 kg N ha−1 from application in 7 years and reduce GWP by 6.2% in CW system compared to CT (P < 0.05). A 25% N saving under PBB75N + R without compromising crop productivity and reduction in global warming potential (GWP) may be a strategy for sustainability of the CW rotation. Thus, the CW rotation with CA-based PBB100N + R and PBB75N + R may be adopted in the IGP of India with higher crop and water productivity, profitability, carbon stock and lower GWP.

Introduction Conservation agriculture (CA) is emerging as an eco-friendly and sustainable approach to food production in South Asia. CA, characterized by reduced tillage, soil surface cover through retaining crop residue or raising cover crops, and crop diversification, enhances crop production and soil fertility. Fungal communities in the soil play a crucial role in nutrient recycling, crop growth, and agro-ecosystem stability, particularly in agricultural crop fields. Methods This study investigates the impact of seven combinations of tillage and crop residue management practices of agricultural production systems, including various tillage and crop residue management practices, on soil fungal diversity. Using the Illumina MiSeq platform, fungal diversity associated with soil was analysed. Results and discussion The results show that the partial CA-based (pCA) production systems had the highest number of unique operational taxonomic units (OTUs) (948 OTUs) while the conventional production system had the lowest number (665 OTUs). The major fungal phyla identified in the topsoil (0–15 cm) were Ascomycota, Basidiomycota, and Mortierellomycota, with their abundance varying across different tillage-cum-crop establishment (TCE) methods. Phylum Ascomycota was dominant in CA-based management treatments (94.9±0.62), followed by the partial CA (pCA)-based treatments (91.0 ± 0.37). Therefore, CA-based production systems play a crucial role in shaping soil fungal diversity, highlighting their significance for sustainable agricultural production.

Climate change and variability are increasingly affecting agriculture and livelihoods in developing countries, with India being particularly vulnerable. Drought is one of the major climatic constraints impacting large parts of the world. We examined the effects of drought on crop productivity, evaluated the effectiveness of technologies in mitigating these impacts and quantified the resilience gained due to technology adoption. Resilience score and resilience gain are the two indicators used to quantify resilience. The study utilized data gathered from two villages situated in Karnataka, southern India, which have implemented the National Innovations in Climate Resilient Agriculture (NICRA) program, along with data from one control village. Drought has significantly impacted the yields, and the extent of reduction ranged from 23 to 62% compared to the normal year. Adoption of climate-resilient technologies, including improved varieties, water management and livestock practices proved beneficial in increasing yield and income during drought years. The resilience score of various technologies ranged from 71 to 122%, indicating that the technologies had realized an increase in yields in the drought year in comparison to the normal year. The extent of resilience gain ranged from 7 to 68%, indicating that the adoption of technologies contributed to the yield advantage over the farmers’ practice during drought. Water harvesting and critical irrigation have the highest resilience scores and gains, and in situ moisture conservation practices such as trench cum bunding (TCB) have comparable resilience scores and gains. The diversification of enterprises at the farm has a higher resilience score and gain. There is a need to identify climate-resilient technologies that can achieve higher resilience, as the solutions are context-specific. Further, promising technologies need to be scaled by adopting multiple approaches and by creating an enabling environment so as to increase resilience in agricultural systems.

Financial Viability and Cost Estimation of SSD in water logged saline soil of India