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Diurnal Variations in the Air Pollutants Concentration over Haryana, India, and Understanding their Emission Sources
2022
Mor, Sahil | Bhukal, Santosh | Bishnoi, Narsi Ram | Ravindra, Khaiwal
India's Indo-Gangetic Plain (IGP) region has become the global hotspot of air pollution, and stubble burning in northern India has increased the concern due to its impact on air quality and health. The current study focuses on studying the diurnal variation of air pollutants for the first time covering Haryana, India, and identifying the sources responsible for air pollutants emissions during the different seasons of the year. Based on ecology and cropping pattern, the study area was divided in three zones. In all seasons, the diurnal peak concentrations of particulate matter (PM₂.₅ and PM₁₀) were found highest in Zone 2 as compared to Zone 1 and Zone 3, which can be due to the high polluting districts located in Zone 2 including Hisar where thermal power plants, stainless steel producing industry and pulp and paper industry are located along with district Faridabad which is known as the industrial capital of Haryana. The lowest average hourly concentration of PM₁₀ and PM₂.₅ was found in late afternoon hours in winter, pre-monsoon and post-monsoon season in all three zones due to a decrease in traffic volumes which lead to low emission rates along with increase in the mixing height which cause favorable dispersion conditions. The lowest hourly mean concentration of CO, NOₓ and NH₃ in all zones was found during the afternoon hours in all seasons. The study also focuses on understanding the day and time patterns and the maxima and minima of pollutants concentrations in different zones of Haryana.
Afficher plus [+] Moins [-]Earthworms to improve glyphosate degradation in biobeds
2020
Lescano, Maia R. | Masin, Carolina E. | Rodríguez, Alba R. | Godoy, José L. | Zalazar, Cristina S.
In this work, earthworm effect on the efficiency of biobeds for glyphosate degradation was studied. Three biomixtures with and without the addition of earthworms (Eisenia fetida species) were evaluated. The initial concentration of glyphosate was 1000 mg/kg biomixture. Glyphosate and biological parameters were measured as a function of time. Earthworm survival, biomass, and reproduction were evaluated as well. All biomixtures that contain earthworms reached 90% of glyphosate degradation at 90 days in comparison with the biomixtures without earthworms that reached 80% approximately at the same time. Also, within the biomixtures that contained earthworms, glyphosate degradation rate was significantly higher in the one made up with soil and wheat stubble (Ws-E) showing excellent capacity for aminomethylphosphonic acid (AMPA) degradation, the main metabolite of glyphosate degradation. In addition, a study performed after the vermiremediation process showed that E. fetida can tolerate high glyphosate concentration without modifications in its life traits. It can be concluded that the use of E. fetida within the biobeds is an excellent combination to improve glyphosate and AMPA removal.
Afficher plus [+] Moins [-]Climate neutral in agricultural production system: a regional case from China
2021
Chen, Ru | Zhang, Ruoyan | Han, Hongyun
The concept of climate neutral has been introduced in the agricultural production system to re-examine the connotation of agricultural carbon footprint (CF). According to the integrated accounting framework of the agricultural CF we built, then selected a case from China, and carried out the climate economic effect quantitative analysis of the agricultural production system. The results indicated that CO₂ emissions accounted the largest percentage of total carbon emissions by 52.05%, which was driven strongly by the application of agricultural fertilizers and consumption of diesel oil and CH₄ emissions (ME) from cattle fed intestinal fermentation, and the driving force behind carbon sequestration was derived from the woody cash crops of carbon sequestration by vegetation and the input of residual carbon from straw returning to field and root stubble in the soil carbon pool. The carbon sink finally realized in the agricultural production system and the agricultural CF index reflected the surplus of 1.801 Mt C in the study area. In addition, we used the indicators of carbon density, carbon intensity, and carbon efficiency to judge the trade-offs of cost-benefit between the agroecosystem and economic system, so as to put forward some potential mitigation strategies for the study area. The mitigative effect of agricultural production system on climate neutral need to be further estimated in a more rigorous manner while controlling for more uncertainties in the future.
Afficher plus [+] Moins [-]Azolla pinnata, Aspergillus terreus, and Eisenia fetida for fasterrecycling of nutrients from wheat straw
2019
Arora, Manveen | Arawindara Kaura,
A vast amount of surplus wheat straw/stubble (a carbon-rich bioresource) is wasted every year by burning. Harmful gases and residue matter released due to burning cause harmful effects on the environment and human health. Therefore, there is a strong need to recycle this bioresource in a sustainable manner. In the present study, wheat straw (W) was spiked with cattle dung (C), Azolla pinnata (A), and Aspergillus terreus (F) to make eight different treatments (1 kg each), viz. W (1 kg), WC (666 g + 334 g), WA (980 g + 20 g), WF (980 g + 20 ml), WCF (666 g + 314 g + 20 ml), WCA (666 g + 314 g + 20 g), WFA (960 g+ 20 ml + 20 g), and WCFA(666 g + 294 g + 20 ml + 20 g), and subjected to vermicomposting (Vcom) and aerobic composting (Acom). A comparison was made for the time required for degradation and nutrient profile of the products. The fastest recycling of wheat straw/stubble (120 days) was observed in WCA and WCFA, but the nutrient quality of WCA was better (N 18.67, P 3.88, K 38.84 g/kg). In the Acom group, longer time was required for degradation of various mixtures, but in this group also, WCA was degraded first of all (138 days) and yielded a product with the best nutrient quality (N 14.77, P 2.56, K 28.80 g/kg). Maximum growth of E. fetida and maximum number of hatchlings were observed in WCA while the highest cocoon production was observed in WCFA. It was observed that azolla enhanced conversion of wheat straw into a nutrient-rich product for agronomic use. Thus its use will reduce the amount of cattle dung in the mixture and the bulk to be handled by the farmers for ecosafe disposal of surplus straw/stubble. Therefore, this technology can be adopted as an alternative to burning.
Afficher plus [+] Moins [-]Ambient air quality changes after stubble burning in rice–wheat system in an agricultural state of India
2019
Grover, Dipti | Chaudhry, Smita
Ground-based ambient air monitoring was conducted to assess the contribution of crop residue burning of wheat (Triticum aestivum) and rice (Oriza sativa) at different locations in three districts (Kaithal, Kurukshetra, and Karnal) of the agricultural state of Haryana in India for two successive years (2016 and 2017). The Air Quality Index (AQI) and concentration of primary pollutants (SOₓ, NOₓ, and PM₂.₅) were determined in rice and wheat crop season, for burning and non-burning periods. During crop residue burning periods, concentrations of SOₓ, NOₓ, and PM₂.₅ were exceeded the NAAQS values by 78%, 71%, and 53%, respectively. A significant increase in SOₓ (4.5 times), NOₓ (3.8 times), and PM₂.₅ concentration (3.5 times) was observed in stubble burning periods as compared to pre-burning (p < 0.05). A positive and significant correlation among the three pollutant concentrations was observed (p < 0.01). The AQI of KA site in Karnal district fell in severely polluted category during 2016 for rice as well as wheat residue burning period, and of KK site in Kaithal during wheat residue burning in year 2017. Results of present study indicate a remarkable increase in pollutant concentration (SOₓ, NOₓ, and PM₂.₅) during the crop residue burning periods. To the best of our knowledge, the outcomes of present study in this region have not been reported in earlier reports. Hence, there is an urgent need to curb air pollution by adopting sustainable harvesting technologies and management of residues.
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