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471.
V.?Krishna?PrasadEmail author Ben?Stinner Deb?Stinner John?Cardina Richard?Moore Prabhat?K.?Gupta Harao?Tsuruta Kiyoto?Tanabe K.?V.?S.?Badarinath Casey?Hoy 《Regional Environmental Change》2003,3(4):154-161
We studied trends in food production and nitrous oxide emissions from India's agricultural sector between 1961 and 2000. Data
from Food and Agricultural Statistics (FAO) have been gathered covering production, consumption, fertilizer use and livestock
details. IPCC 1996 revised guidelines were followed in studying the variations in N2O-N emissions. Results suggest that total N2O-N emissions (direct, animal waste and indirect sources) increased ~6.1 times from ~0.048 to ~0.294 Tg N2O-N, over 40 years. Source-wise breakdown of emissions from 1961–2000 indicated that during 1961 most of the N2O-N inputs were from crop residues (61%) and biological nitrogen fixation (25%), while during 2000 the main sources were synthetic
fertilizer (~48%) and crop residues (19%). Direct emissions increased from ~0.031 to ~0.183 Tg. It is estimated that ~3.1%
of global N2O-N emissions comes from India. Trends in food production, primarily cereals (rice, wheat and coarse grains) and pulses, and
fertilizer consumption from 1961–2000 suggest that food production (cereals and pulses) increased only 3.7 times, while nitrogenous
fertilizer consumption increased ~43 times over this period, leading to extensive release of nitrogen to the atmosphere. From
this study, we infer that the challenge for Indian agriculture lies not only in increasing production but also in achieving
production stability while minimizing the impact to the environment, through various management and mitigation options. 相似文献
472.
Dinesh Bhatt Shreedhar Maskey Mukand S. Babel Stefan Uhlenbrook Krishna C. Prasad 《Regional Environmental Change》2014,14(4):1291-1301
Understanding crop responses to climate is essential to cope with anticipated changes in temperature and precipitation. We investigated the climate–crop yield relationship and the impact of historical climate on yields of rice, maize and wheat in the Koshi basin of Nepal. The results show significant impact of growing season temperature and precipitation on crop production in the region. Rice, maize and wheat cultivated at altitudes below 1,100, 1,350 and 1,700 m amsl (above mean sea level), respectively, suffer from stress due to higher temperatures particularly during flowering and yield formation stages. Responses of crop yields to a unitary increment in growing season mean temperature vary from ?6 to 16 %, ?4 to 11 % and ?12 to 3 % for rice, maize and wheat, respectively, depending on the location and elevation in the basin. In most parts of the basin, we observe warming trends in growing season mean temperatures of rice, maize and wheat over the last few decades with clear evidence of negative impacts on yields. However, at some high-elevation areas, positive impacts of warming are also observed on rice and maize yields. If the observed trends in temperature continue in future, the impact is likely to be mostly negative on crop production in the basin. However, crop production may gain from the warming at relatively higher altitudes provided other conditions, e.g., water availability, soil fertility, are favorable. 相似文献
473.
474.
Mandal Reema Das Anirban Sudheer A. K. Kumar Sanjeev Verma Sangeeta Gaddam Mahesh Deshpande R. D. 《Environmental geochemistry and health》2021,43(10):4043-4059
Environmental Geochemistry and Health - Fluoride contamination in groundwaters of a rural region in semi-arid Western India has been studied using combination of geochemical-and-isotopic... 相似文献
475.
Ensilage of pineapple processing waste for methane generation 总被引:3,自引:0,他引:3
Pineapple peel wastes, which are seasonal, comprise of peels and rags. Their disposal poses a serious environmental pollution problem. Since pineapple peel is rich in cellulose, hemicellulose and other carbohydrates it was found to be a potential substrate for methane generation by anaerobic digestion. Ensilaging of pineapple peel resulted in the conversion of 55% carbohydrates into volatile fatty acids. The ensilage of pineapple processing wastes reduced the biological oxygen demand by 91%. Biogas digester fed with ensilaged pineapple peel resulted in the biogas yield of 0.67 m3/kg volatile solids (VS) added with methane content of 65% whereas fresh and dried pineapple peels gave biogas yields of 0.55% and 0.41 m3/kg VS added and methane content of 51% and 41% respectively. 相似文献
476.
Biomass fuels are used by the majority of resource poor households in low-income countries. Though biomass fuels, such as
dung-briquette and firewood are apparently cheaper than the modern fuels indoor pollution from burning biomass fuels incurs
high health costs. But, the health costs of these conventional fuels, mostly being indirect, are poorly understood. To address
this gap, this study develops probit regression models using survey data generated through interviews from households using
either dung-briquette or biogas as the primary source of fuel for cooking. The study investigates factors affecting the use
of dung-briquette, assesses its impact on human health, and estimates the associated household health costs. Analysis suggests
significant effects of dung-briquette on asthma and eye diseases. Despite of the perception of it being a cheap fuel, the
annual health cost per household due to burning dung-briquette (US16.94) is 61.3 (US 16.94) is 61.3% higher than the annual cost of biogas
(US 10.38), an alternative cleaner fuel for rural households. For reducing the use of dung-briquette and its indirect health
costs, the study recommends three interventions: (1) educate women and aboriginal people, in particular, and make them aware
of the benefits of switching to biogas; (2) facilitate tree planting in communal as well as private lands; and (3) create
rural employment and income generation opportunities. 相似文献
477.
Krishnasamy Lakshmi Krishna Kadirvelu Subpiramaniyam Sivakumar 《Environmental science and pollution research international》2022,29(36):54282-54291
Environmental Science and Pollution Research - Polyacrylonitrile (PAN)-based-modified zinc oxide (ZnO) nanofibers were synthesized by using electrospinning and hydrothermal techniques. The... 相似文献
478.
Krishnani Kishore Kumar Boddu Veera Mallu Chadha Narinder Kumar Chakraborty Puja Kumar Jitendra Krishna Gopal Pathak Himanshu 《Environmental science and pollution research international》2022,29(54):81130-81165
Environmental Science and Pollution Research - Global agriculture is facing tremendous challenges due to climate change. The most predominant amongst these challenges are abiotic and biotic... 相似文献
479.
This study addresses the effect of political transition and subsequent timber bans on forest loss in Myanmar, in the context of identified drivers. Cook’s Distance (CD) was applied to remotely sensed time-series forest loss dataset to measure the effect of the events. Forest loss derived fragmentation metrics were linked to drivers at a landscape scale. Results show that at the national level, the political transition in 2011 had maximum effect (CD 0.935) on forest loss while the timber bans decreased forest loss by 612.04 km2 and 213.15 km2 in 2015 and 2017 (CD 0.146 and 0.035), respectively. The effect of the events varied for different States/Regions. The dominant drivers of change shifted from plantations in 2011 to infrastructure development in 2015. This study demonstrates the effects of policy on forest loss at various scales and can inform decision-makers for forest conservation, planning and development of mitigation measures. 相似文献
480.
Wet scrubber analysis of volatile organic compound removal in the rendering industry 总被引:1,自引:0,他引:1
The promulgation of odor control rules, increasing public concerns, and U.S. Environmental Protection Agency (EPA) air regulations in nonattainment zones necessitates the remediation of a wide range of volatile organic compounds (VOCs) generated by the rendering industry. Currently, wet scrubbers with oxidizing chemicals are used to treat VOCs; however, little information is available on scrubber efficiency for many of the VOCs generated within the rendering process. Portable gas chromatography/mass spectrometry (GC/MS) units were used to rapidly identify key VOCs on-site in process streams at two poultry byproduct rendering plants. On-site analysis was found to be important, given the significant reduction in peak areas if samples were held for 24 hr before analysis. Major compounds consistently identified in the emissions from the plant included dimethyl disulfide, methanethiol, octane, hexanal, 2-methylbutanal, and 3-methylbutanal. The two branched aldehydes, 2-methylbutanal and 3-methylbutanal, were by far the most consistent, appearing in every sample and typically the largest fraction of the VOC mixture. A chlorinated hydrocarbon, methanesulfonyl chloride, was identified in the outlet of a high-intensity wet scrubber, and several VOCs and chlorinated compounds were identified in the scrubbing solution, but not on a consistent basis. Total VOC concentrations in noncondensable gas streams ranged from 4 to 91 ppmv. At the two plants, the odor-causing compound methanethiol ranged from 25 to 33% and 9.6% of the total VOCs (v/v). In one plant, wet scrubber analysis using chlorine dioxide (ClO2) as the oxidizing agent indicated that close to 100% of the methanethiol was removed from the gas phase, but removal efficiencies ranged from 20 to 80% for the aldehydes and hydrocarbons and from 23 to 64% for total VOCs. In the second plant, conversion efficiencies were much lower in a packed-bed wet scrubber, with a measurable removal of only dimethyl sulfide (20-100%). 相似文献