Index for refining soil health assessment through multivariate approach under diverse agro-climatic zones in the Indo-Gangetic basin of Bihar.

A fundamental necessity in advancing sustainable crop production lies in the establishment of a reliable technique for assessing soil health. Soil health assessment is a challenge considering multiple interactions among dynamic indicators within various management strategies and agroecological contexts. Hence a study was conducted to determine the soil health variables, quantify the soil health index (SHI), and validate them with the productivity of rice (Oryza sativa L.)-wheat (Triticum aestivum L.) system for the Indo Gangetic basin of Bihar, India, under four contrasting agro-climatic zones (ACZ-I, II, IIIA & IIIB). For this study, 100 soil samples (0-15 cm) from each ACZ with a total of 400 soil samples were obtained for analyzing 20 soil health variables (soil physical, chemical, and biological properties). To identify SHI and important soil health variables, principal component analysis (PCA) was employed. Apart from specific variables, soil pH, soil organic carbon (SOC), available Zn and available water capacity (AWC) were identified as common indicators for the four ACZs. Results revealed that under the rice-wheat cropping system, ACZ-IIIB soils had a higher SHI (0.19-0.70) than other ACZs. SHI of ACZ-IIIB was significantly influenced by SOC (19.32 %), available P (10.52 %), clay (10.43 %), pH (10.80 %), and soil respiration (9.8 %). The strong relationship between SHI and system productivity of the rice-wheat (R2 = 0.79) system indicates that the selected soil health variables are representative of good soil health. It is concluded that ACZ-specific SHIs are a promising strategy for evaluating and monitoring soil health to achieve the United Nations' Sustainable Development Goal of 'zero hunger' by 2030.

Are livelihoods of slum dwellers sustainable and secure in developing economies? Evidences from Lucknow, Uttar Pradesh in India.

Objectives: We adopted the Sustainable Livelihood Security (SLS) approach to assess the living conditions of slum dwellers in Lucknow, Uttar Pradesh, India. Keeping the urban poor at the centre, we attempted to bring out the multidimensional nature of poverty and explored various aspects of the livelihood of slum dwellers. Methods: We surveyed 900 households from both notified and non-notified slums of Lucknow city to construct the SLS index, keeping the social, economic, infrastructural, health, and micro-environmental aspects of slum dwellers in the background. We collected data based on the household approach of the UN and the neighbourhood approach of the Government of India and aggregated the weighted index values under various sub-components to construct a composite index. Results: The results suggested that the index values were low for both types of slum dwellers in Lucknow city specifically in the economic, infrastructural, and micro-environmental aspects. The results also showed that 'non-notified slum dwellers' were much more deficient in all the dimensions compared to their 'notified' counterparts. The livelihood condition of the marginalized households (backward castes and minorities) was especially precarious and vulnerable. Conclusion: The findings reveal the existence of a high level of informality of livelihood of the urban poor in terms of housing, employment, health, and other basic amenities, and demonstrate that their livelihood condition is characterized by a low assets base, and poor strategies to overcome exigencies and risks. Recommendations: This paper recommends enactment of an urban employment guarantee act, conducting of sabhas (meetings) at the ward level on a regular basis to promote awareness, and notification of non-notified slums to notified slums on regular basis for the overall development of slum dwellers.

Conventional and Zero Tillage with Residue Management in Rice-Wheat System in the Indo-Gangetic Plains: Impact on Thermal Sensitivity of Soil Organic Carbon Respiration and Enzyme Activity.

The impact of global warming on soil carbon (C) mineralization from bulk and aggregated soil in conservation agriculture (CA) is noteworthy to predict the future of C cycle. Therefore, sensitivity of soil C mineralization to temperature was studied from 18 years of a CA experiment under rice-wheat cropping system in the Indo-Gangetic Plains (IGP). The experiment comprised of three tillage systems: zero tillage (ZT), conventional tillage (CT), and strip tillage (ST), each with three levels of residue management: residue removal (NR), residue burning (RB), and residue retention (R). Cumulative carbon mineralization (Ct) in the 0-5 cm soil depth was significantly higher in CT with added residues (CT-R) and ZT with added residues (ZT-R) compared with the CT without residues (CT-NR). It resulted in higher CO2 evolution in CT-R and ZT-R. The plots, having crop residue in both CT and ZT system, had higher (p < 0.05) Van't-Hoff factor (Q10) and activation energy (Ea) than the residue burning. Notably, micro-aggregates had significantly higher Ea than bulk soil (~14%) and macro-aggregates (~40%). Aggregate-associated C content was higher in ZT compared with CT (p < 0.05). Conventional tillage with residue burning had a reduced glomalin content and ß-D-glucosidase activity than that of ZT-R. The ZT-R improved the aggregate-associated C that could sustain the soil biological diversity in the long-run possibly due to higher physical, chemical, and matrix-mediated protection of SOC. Thus, it is advisable to maintain the crop residues on the soil surface in ZT condition (~CA) to cut back on valuable C from soils under IGP and similar agro-ecologies.

Application of Sewage Sludge in a Rice (Oryza sativa L.)-Wheat (Triticum aestivum L.) System Influences the Growth, Yield, Quality and Heavy Metals Accumulation of Rice and Wheat in the Northern Gangetic Alluvial Plain.

For a sustainable and profitable agriculture production system, balanced and integrated use of nutrients is a key strategy. In addition, partial replacement of chemical fertilizers with organics ones reduces both environmental concerns and economic costs and provides greater soil health benefits. With this hypothesis, an experiment was conducted to assess the yield and economic benefits of a rice-wheat cropping system (RWCS) as influenced by the joint application of sewage sludge (SSL) and fertilizer. The treatments comprised: without fertilizer or SSL; 100% recommended dose of fertilizers (RDF); 100% RDF + 20 Mg ha-1 SSL; 100% RDF + 30 Mg ha-1 SSL; 50% RDF + 20 Mg ha-1 SSL; 60% RDF + 20 Mg ha-1 SSL; 70% RDF + 20 Mg ha-1 SSL; 50% RDF + 30 Mg ha-1 SSL; 60% RDF + 30 Mg ha-1 SSL and 70% RDF + 30 Mg ha-1 SSL. The experiment was laid out in a randomized block design with three replications. The result of our study indicate that the highest percent increase in mean plant height i.e., ~14.85 and ~13.90, and grain yield i.e., ~8.10 and ~18.90 for rice and wheat, respectively, were recorded under 100% RDF + 30 Mg SSL ha-1 treatment compared to 100% RDF, while 70% RDF + 20 Mg ha-1 SSL produced a statistically equivalent grain yield of 100% RDF in RWCS. The application of 20 and 30 Mg SSL ha-1 along with recommended or reduced fertilizer dose, significantly increased the heavy metal content in plant and soil systems above that of 100% RDF, but this enhancement was found within permissible limits. Moreover, the reduced use of SSL i.e., 20 Mg SSL ha-1, resulted in lower heavy metal content in grain and soil than did the 30 Mg ha-1 SSL treatment, but significantly higher than in the absolute control or 100% RDF treatment. In summary, the use of 20 Mg ha-1 SSL along with 70% RDF provided a safer, profitable and sustainable option in a rice-wheat cropping system in the middle Ganegatic alluvial plain.

The potential of arbuscular mycorrhizal fungi in C cycling: a review.

Arbuscular mycorrhizal fungi (AMF) contribute predominantly to soil organic matter by creating a sink demand for plant C and distributing to below-ground hyphal biomass. The extra-radical hyphae along with glomalin-related soil protein significantly influence the soil carbon dynamics through their larger extent and turnover period need to discuss. The role of AMF is largely overlooked in terrestrial C cycling and climate change models despite their greater involvement in net primary productivity augmentation and further accumulation of this additional photosynthetic fixed C in the soil. However, this buffering mechanism against elevated CO2 condition to sequester extra C by AMF can be described only after considering their potential interaction with other microbes and associated mineral nutrients such as nitrogen cycling. In this article, we try to review the potential of AMF in C sequestration paving the way towards a better understanding of possible AMF mechanism by which C balance between biosphere and atmosphere can be moved forward in more positive direction.

Arbuscular mycorrhizal fungi mediated salt tolerance by regulating antioxidant enzyme system, photosynthetic pathways and ionic equilibrium in pea (Pisum sativum L.).

Arbuscular mycorrhizal (AM) fungi play an important role in improving the plant tolerance to salt stress. In the present study, we investigated the influence of AM fungi inoculation on various physiological, biochemical and nutritional aspects of pea grown under salt stress. The AM fungi inoculation successfully reduced the negative effects of salinity by improving the antioxidant enzyme system, a greater accumulation of compatible organic solutes, a higher content of photosynthetic pigment and a balanced uptake of nutrients, which resulted in higher growth and yield. Seed yield was found to be significantly higher by ~ 24, 40 and 54% in T2 (Rhizoglomus intraradices), T3 (Funneliformis mosseae and R. intraradices) and T4 (Rhizoglomus fasciculatum and Gigaspora sp.), respectively, as compared to nonmycorrhizal plants. Overall, a mixed application of R fasciculatum and Gigaspora sp. was superior to other mycorrhizal treatments, which can be attributed to specific compatibility relationships or functional complementarity that exists between symbionts.