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A limiting factor in land application of sewage sludge is the resultant heavy metal accumulation in soils followed by biomagnification in the food chain, posing a potential hazard to animal and human health. In view of this fact, pot experiments were conducted to evaluate the effect of digested sludge application to soil on phytotoxicity of heavy metals such as Cd, Cr, Ni, and Pb to radish (Raphanus sativus L.) plants. Increasing sludge levels resulted in increased levels of DTPA-extractable heavy metals in the soil. Cadmium was the dominant metal extracted by DTPA followed by Ni, Pb, and Cr. The extractability of metals by DTPA tended to decrease from the first to the second crop. Dry matter yield of radish increased significantly as a function of increasing sludge treatments. Soil application of sludge raised the concentration of one or more heavy metals in plants. Shoots contained higher concentrations of Cd, Cr, and Ni than the roots of radish plants. Shoot concentrations of Cd, Cr, Ni, and Pb were within the tolerance levels of this crop at all rates of sludge application. Shoot as well as root concentration of Cd was above 0.5 mg kg −1 , considered toxic for human and animal consumption. The levels of DTPA-extractable Cd and Ni were less correlated while those of Cr and Pb were more correlated with their respective shoot and root contents. The results emphasize that accumulation of potentially toxic heavy metals in soil and their build-up in vegetable crops should not be ignored when sludge is applied as an amendment to land.

Climate change imprints on soil are projected primarily through the changes in soil moisture and surge in soil temperature and CO2 levels in response to climate change and is anticipated to have varying impacts on soil characteristics and processes that are instrumental in the restoration of soil fertility as well as productivity. Climate change encompasses a major concern of sharing its impact on the stability and functionality of soil microbiome and is characterized by one or more chief stability metrics encircling resistance, resilience, and functional redundancy. Nevertheless, the explorations over the past years have unveiled the potential of microbial interventions in the regeneration of soils or assurance of perked-up resilience to crops. The strategies involved therein encompass harnessing the native capability of soil microbes for carbon sequestration, phyto-stimulation, bio fertilization, rhizo-mediation, biocontrol of plant pathogens, enzyme-mediated breakdown, antibiosis, prompting of anti-oxidative defense mechanism, exudation of volatile organic compounds (VOCs) and induced systemic resistance (ISR) response in the host plant. However, the short storage and shelf-life of microbe-based formulations stay a significant constraint and rigorous efforts are necessary to appraise their additive impact on crop growth under changing climate scenarios.

show that during the whole period, average PM 1 concentrations ranged from 15.10 to 108.9 µg/m 3 , PM 2.5 (28.70-577.50 µg/m 3 ), PM 4 (44.50-780.87 µg/m 3 ), PM 10 (57.13-1225.53 µg/m 3 ), total suspended particulates (77.77-1410.27 µg/m 3 ) and CO 2 (332.4-655.0 ppm). The average concentrations of these parameters showed that the maximum PM 1 concentration was found at Dalgate (53.77 µg/m 3 ) and PM 2.5 had its maximum average concentration at Jehangir Chowk (140.13 µg/m 3 ). Other parameters like PM 4 , PM 10 , TSP and CO 2 had a maximum average values at Jehangir Chowk (240.23 µg/m 3 , 633.40 µg/m 3 , 853.50 µg/m 3 and 533.20 ppm, respectively). The pollution load was observed to be maximum during winter season followed by autumn, summer and spring. The lowest concentration of all pollutants except CO 2 was observed in April 2020 and this might be due to COVID-19 lockdown observed in the country during the same period.

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