Qualitative assessment of compost engendered from municipal solid waste and green waste by indexing method.

The present study aims at quantification of the quality of three varieties of composts made from municipal solid waste, green waste and combined waste by critically evaluating their physicochemical attributes, effect on soil fertility and metal pollution risk. Each waste type was treated with effective micro-organisms to compare the compost quality using Quality Control Indices. The effect of microbial consortia on the wastes was prominent resulting in decreased pH levels and increased electrical conductivity. C/N ratio ranged between 14-24 for waste composts without microbial treatment, and 8-11 for microbial treated wastes. The fertility parameter was observed to be more in microbial treated waste composts. Also, heavy metals concentration in waste compost without effective microbial treatment was higher than the types given EM. Based on the fertility and clean indices, the treated and untreated municipal solid waste and combined waste compost belonged to class RU-1 and class D, respectively. Moreover, compost prepared from treated and untreated green waste belonged to classes B and C respectively. In general, the prepared CW and GW composts have medium to high fertilizing potential and are fit for domestic as well as commercial use. However, MSW compost is not fit for agricultural purposes as it didn't improve soil fertility to a greater extent but can be used as a soil conditioner in limited quantity as it can cause metal toxicity. For this reason, proper segregation of inputs at the start of a composting process is necessary to improve its quality before being put to agricultural use as any unbalanced or unchecked content of mixed waste will affect the overall compost quality.Implications: Significance of the work: The research dealt with different combinations of segregated wastes to analyze the best fit solid waste compost. Experiments were conducted on the actual landfill site area to simulate the conditions for the process. The manuscript provides evidence and other facts advocating the use of composting for waste management and ultimately reducing pollution caused by landfilling. It ought to cause a multiplier effect if the same is to be followed in other parts of the world, and thus working our way toward getting the Smart city project to fruition. The results of the study exhibit the differences in physiochemical nature of various types of composts. A treatment of microbial consortium with restrictions enabled a conducive atmosphere in the colonies to thrive faster and initiate the process of decomposition. We observed that treated samples converted faster into compost as compared to non-treated samples. We also observed the effect of treatment on fertility parameters of prepared compost samples. In general, it was found that the organic carbon and C/N ratio declined while the total nitrogen and total potassium was observed to increase with very little to no change in phosphorous content, with the inoculation of beneficial micro-organisms throughout the composting course. A reduction in the heavy metal levels was observed in samples treated with active micro-organisms. The compost classification into A, B, C, and D classes represents the quality of compost and further use in agricultural land on commercial levels. The quality index values were determined highest for green waste compost (GWC). The municipal solid waste compost (MSWC) exhibited lowest index values. Therefore, based on the quality index values, the utilization of GWC will aid in reutilizing the green waste and in boosting soil fertility and reduce the waste quantity generation rates. It's also necessary to make compost making widespread among the farmers for a sustainable environment. The GWC has been considered as a sustainable option of waste management, being economically and ecologically viable.

Management zone delineation and spatial distribution of micronutrients in cold-arid region of India.

The plant health is governed by many factors: soil playing a central role which exhibits huge variability in its characteristics. Micronutrients even though needed in small quantities by plants play an indispensable role in affecting the crop growth and development. The assessment of spatial variability of different soil parameters is incumbent for tackling the loss of crop productivity on account of non-receipt of desirable inputs. The present investigation centered on the spatial distribution of soil parameters and micronutrients was conducted to delineate management zones (MZs) in cold arid region (Kargil) of India for proficient micronutrient management. Overall 454 georeferenced representative soil samples at the depths of 0-15 cm were garnered. The soil samples were processed and analyzed for different soil parameters encompassing pH, EC (electrical conductivity), SOC (soil organic carbon), and available micro-nutrient (iron, manganese, zinc, copper and nickel) concentrations. The distinct variation in the soil properties including micronutrients was identified with coefficient of variation ranging as low as 5.62% to moderate (21.16 to 42.49%) and as high as 159.63%. Semivariogram analysis and ordinary kriging of soil variables under study revealed diverse spatial distribution exhibiting medium to high spatial dependence in the region. PCA (principal component analysis) and K-means clustering were expended for the delineation of MZs. Four principal components (PCs) having eigen values > 1 and accounting for 70% of the total variation were subjected to further analysis. The five potential MZs were demarcated on the basis of K-means cluster performance index, and heterogeneity in parameters was discerned. The results of study corroborate that the spatial variability analysis of different soil parameters for delineation/identification of MZs might be effectually employed for site-specific micronutrient management.

Agricultural soils a trigger to nitrous oxide: a persuasive greenhouse gas and its management.

Agricultural soils form the backbone of the country's economic development. The increased population has not only reduced this treasure but also has affected the global climate at an alarming rate. Among the GHGs, emission of N2O due to agricultural activities is nowadays a global concern. Agricultural industries have increased N2O and CH4 by 17% in the atmosphere since 1990, with an average emanation rate of around 60 MT CO2 equivalents per year. Crop production accounts for approximately 50% of N2O emissions stemming from the farming community and discharges of fertilizer-induced N2O, for the time being estimated by IPCC at 1.24% of the N used ranging from 0.76% (rice) to 2.77% (maize). The concentration of atmospheric N2O has increased (60 ppb) after the industrial revolution, at the pace of 0.73 ppb year-1. Besides, soil structure, temperature, moisture, denitrifying microbial population, pH, C:N ratio, and relief are the factors which significantly enhance the N2O levels into the atmosphere. N2O as a GHG has more potential towards global warming than CO2 and has a very long residence period (115 years) in the atmosphere. N2O emission is nowadays a core issue which needs to be mitigated so as to decline the levels of its production in agricultural soils. However, priority should be given to the organic farming, management of soil chemistry, and phytoremediation to reduce the addition of N2O into the ambient air. Furthermore, deployment of N2O reductase in agricultural soils increases the efficiency of converting N2O to inert N2 which is a valuable strategy to reduce N2O production.