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Enteric methane emission accounts for about 17 per cent of national Green House Gas (GHG) emissions and 60 percent of the GHG emissions from agriculture sector in India. As the losses of methane represent inefficiencies and losses...
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Enteric methane emission accounts for about 17 per cent of national Green House Gas (GHG) emissions and 60 percent of the GHG emissions from agriculture sector in India. As the losses of methane represent inefficiencies and losses of energy in our current production system, it therefore stands to reason that estimates of enteric methane emission have long-run implications for environmental sustainability of dairy farming. The available literature is lacking in geographic region specific methane emission factor which varies based on quantity and quality of feed. Therefore, present study estimated the enteric methane emission from diary animals in semi-arid eastern plain zone of Rajasthan using both primary as well as secondary data. The emission factor for each category of dairy animals was generated using the Tire-II approach proposed by Inter-governmental Panel on Climate Change based on primary data collected from 120 households of Jaipur district of the state selected purposively representing best case in the zone. The results of study showed that the methane factors for lactating local cow, crossbred cow and buffalo were 144.19g, 203.78g and 198.41g/head/day respectively, while dry local cow, crossbred cow and buffalo emitted 124.85g, 190.29gand 173.74g/head/day, respectively. The estimated methane emissions from enteric fermentation of dairy animals in the zone was 10308.37 thousand tones and more than 2/3rd of which was contributed by buffaloes. The methane emission in relation to milk production was worked out 75.72 g/kg of milk and reported highest in case of crossbred cattle (147.56g/kg milk). Study suggests for incorporating energy efficient diets such as concentrates and by-products of sugar industry, maintaining the livestock population in relation to carrying capacity, improving the productivity on animals, etc. for reducing the methane emission in the zone.
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For evaluating the applicability of the soil gradient method as a substitute for CO2-, CH4-, and N2O-flux measurements in steppe, we carried out chamber measurements and determined soil gas concentration at an ungrazed (UG99) and ...
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For evaluating the applicability of the soil gradient method as a substitute for CO2-, CH4-, and N2O-flux measurements in steppe, we carried out chamber measurements and determined soil gas concentration at an ungrazed (UG99) and a grazed (WG) site in Inner Mongolia, China. The agreement of the concentration-based flux estimates with measured chamber-based fluxes varied largely depending on the respective GHG in the sequence CO2 > CH4 >> N2O. A calibration of the gas-transport parameter used to calculate fluxes based on soil gas concentrations improved the results considerably for CO2 and CH4. After calibration, the average deviation from the chamber-based annual cumulative flux for both sites was 11.5%, 10.5%, and 59% for CO2, CH4, and N2O. The gradient method did not constitute an adequate stand-alone substitute for greenhouse-gas flux estimation since a calibration using chamber-based measurements was necessary and vigorous production processes were confined to the uppermost, almost water-saturated soil layer.
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摘要 :
For evaluating the applicability of the soil gradient method as a substitute for CO2-, CH4-, and N2O-flux measurements in steppe, we carried out chamber measurements and determined soil gas concentration at an ungrazed (UG99) and ...
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For evaluating the applicability of the soil gradient method as a substitute for CO2-, CH4-, and N2O-flux measurements in steppe, we carried out chamber measurements and determined soil gas concentration at an ungrazed (UG99) and a grazed (WG) site in Inner Mongolia, China. The agreement of the concentration-based flux estimates with measured chamber-based fluxes varied largely depending on the respective GHG in the sequence CO2 > CH4 >> N2O. A calibration of the gas-transport parameter used to calculate fluxes based on soil gas concentrations improved the results considerably for CO2 and CH4. After calibration, the average deviation from the chamber-based annual cumulative flux for both sites was 11.5%, 10.5%, and 59% for CO2, CH4, and N2O. The gradient method did not constitute an adequate stand-alone substitute for greenhouse-gas flux estimation since a calibration using chamber-based measurements was necessary and vigorous production processes were confined to the uppermost, almost water-saturated soil layer.
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The increasing concentration of greenhouse gas (GHG) emissions due to increased fossil fuel consumption for manufacturing activities to support population growth is worrisome. Carbon dioxide (CO2) and methane (CH4) remain the two ...
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The increasing concentration of greenhouse gas (GHG) emissions due to increased fossil fuel consumption for manufacturing activities to support population growth is worrisome. Carbon dioxide (CO2) and methane (CH4) remain the two GHGs that contribute to the impact of global warming, and inventorying their concentrations is important for monitoring their changes, which can be used to infer their emissions over time. Hence, this article highlights sniffer4D, an unmanned aerial vehicle (UAV)-based air pollutant mapping system that visualise and analyse three-dimensional (3D) air pollution data in real time, for mapping GHGs concentrations within industrial areas. Consequently, GHGs concentrations for two industrial and adjacent residential areas in Johor, Peninsular Malaysia were mapped. The GHGs concentrations were validated using a ground-based portable gas detector. The results revealed that CO2 has the highest concentration mean of 625.235 mg/m3, followed by CH4 with a mean of 249.239 mg/m3. The mapped UAV GHG concentration also reported good agreement with the in situ observations with an RMSE of 7 and 6 mg/m3 for CO2 and CH4 concentration, respectively. Ozone and nitrogen dioxide mixture (O3 + NO2) with a mean concentration of 249 μg/m3 and an RMSE of 9 μg/m3 are the remaining significant concentrations reported. This approach shall assist in fast-tracking the United Nations climate change mitigation agenda.
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Recycling nutrients helps to reduce the environmental impact of agriculture and contributes to alleviating the
effects of global climate change. A recent trend in sugarcane cultivation is the application of concentrated vinasse
...
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Recycling nutrients helps to reduce the environmental impact of agriculture and contributes to alleviating the
effects of global climate change. A recent trend in sugarcane cultivation is the application of concentrated vinasse
(CV) combined with fertilizers into an organo-mineral formulation to improve logistics, reduce costs and foster
the circular economy. However, the implications of the application of such organo-mineral formulation in
sugarcane fields are unclear. In this study, we evaluated the effects of the organo-mineral formulation containing
granular urea (UR), and a nitrification inhibitor (NI) on crop yields, NH_3 volatilization, and N_2O emissions. Field
experiments were conducted during two fertilization seasons, dry and wet, and the treatments were: control; UR;
UR + NI; CV; CV + UR; and CV + UR + NI. CV was applied at 7 m~3 ha~(-1). The treatments (except control and CV)
were balanced to receive the same amount of N and K. Compared with UR, the organo-mineral formulation of CV
+ UR decreased NH_3 volatilization losses from 7% to 4% in the dry season and from 3.5% to 0.5% in the wet
season. Conversely, compared with UR, N_2O emissions increased significantly (p ≤ 0.05) in CV + UR in the wet
season from 1% to 2% of applied N. In the dry season, no differences were observed. The addition of NI was
effective in mitigating N_2O emissions in both seasons. Emission reductions ranged from 43 to 48% in the dry
season and from 71 to 84%, in the wet season. Fertilization with UR or the organo-mineral formulation influenced
sugarcane yield only in the dry season, with the highest yield in CV + UR. NI did not affect crop yield. In
general, emission intensities (kg CO_2eq Mg~(-1) of stalk) were highest in CV + UR. We conclude that the organomineral
formulation reduced NH_3 losses and increased N_2O emissions compared with regular solid fertilizer
and that NI was effective for mitigating N_2O emissions.
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Land degradation and global warming are currently highly active research topics. Land degradation can both change land cover and surface climate and significantly influence atmospheric circulation. Researches have verified that ca...
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Land degradation and global warming are currently highly active research topics. Land degradation can both change land cover and surface climate and significantly influence atmospheric circulation. Researches have verified that carbon dioxide (CO_2) and methane (CH_4) are major greenhouse gases (CHG) in the atmosphere and are directly affected by human activity. However, to date, there is no research on the spatial distribution of GHG concentrations and also no research on how land degradations affect GHG concentrations in arid and semi-arid regions. In this study, we used GHG data from the ENVlronment SATellite (ENVISAT) and the Greenhouse gases Observing Satellite (GOSAT), the Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) data from the MODerate resolution Imaging Spectroradiometer (MODIS) and precipitation data from ground stations to analyze the way land degradation affects GHG concentrations in northern China and Mongolia, which exhibit the most serious land degradation process in East Asia. Our research revealed that the CO_2 and CH_4 concentrations (XCO_2 and XCH_4) increased from 2003 to 2009 and then decreased into 2011. We used geostatistics to predict and simulate the spatial distribution of XCO_2 and XCH_4 and found that the distribution of XCO2 displays a seasonal trend and is primarily affected by plant photosynthesis, soil respiration and precipitation. As the distribution of XCH_4 is mainly affected by the sources' distribution, microbial processes, LST and submarine hydrate, the CH_4 concentration presents no obvious seasonal changes and the high XCH4 values are primarily found in northeast and southeast China. Land degradation increases the concentration of GHG: the correlation coefficient between NDVI and XCO_2 is R~2 = 0.76 (P < 0.01) and the value between NDVI and XCH_4 is R~2 = 0.75 (P < 0.01).
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Cooling towers are indispensable components for heat rejection in concentrated solar power (CSP) plants. However, the overall performance of CSP plants relies heavily on the choice of cooling tower technology. This paper aims at a...
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Cooling towers are indispensable components for heat rejection in concentrated solar power (CSP) plants. However, the overall performance of CSP plants relies heavily on the choice of cooling tower technology. This paper aims at assessing the impact of cooling tower technology on CSP plant from performance, economic, and environmental perspectives. To achieve this goal, seven CSP projects worldwide with distinct features were selected, and multiple simulations on System Advisor Model software were performed to evaluate the annual energy production, capacity factor, and levelized cost of electricity (LCOE). Moreover, the impact assessment was performed in terms of key metrics, such as discounted payback period (DPP), savings-to-investment ratio (SIR), greenhouse gases (GHG) emissions, water-saving, and total costs savings (TCS) including energy, carbon and water costs savings. The results showed that the wet cooling technology achieved the highest performance findings followed by hybrid and dry cooling technologies. The environmental analysis revealed that the wet cooling technology could avoid roughly 7.02% and 2.93% of GHG emissions compared to dry and hybrid cooling ones, respectively; however, it was found that dry and hybrid cooling technologies could be more profitable in arid regions with water scarcity, since they could save on average 93.30% and 69.83% of water, respectively, compared to the wet technology. Furthermore, the economic results showed that wet and hybrid cooling towers exhibit the best costeffectiveness over dry cooling one as the LCOE was found to be $0.231/0.244 per kWh, and the DPP ranged between 13.41 and 23.46/14.95 and 34.75 years by integrating wet/hybrid technologies in CSP plants. Overall, wet and hybrid cooling technologies yield better TCS and SIR outcomes over dry cooling one. However, with respect to energy conservation, water savings, and GHG emissions savings, hybrid cooling tower could be considered as an optimal technology. This paper is expected to be a guideline for selecting the most cost-effective and eco-friendly cooling technology for future CSP plants, based on key criteria.
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The incorporation of post-harvest crop straw and application of industrial and agricultural wastes to paddy soils increase rice crop yields and soil fertility. However, the impacts of combined applications of straw and waste produ...
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The incorporation of post-harvest crop straw and application of industrial and agricultural wastes to paddy soils increase rice crop yields and soil fertility. However, the impacts of combined applications of straw and waste products on greenhouse gas (GHG) emissions and global warming potential (GWP) of paddy soils are unclear. Therefore, we conducted a field experiment in subtropical rice in China to test the effects of applications of straw, straw + biochar, straw + shell slag, straw + gypsum slag, straw + silicon, and straw+steel slag on rice yields, GWP, and greenhouse gas emission intensity (GHGI). The results showed that, compared to the control, cumulative emissions of carbon dioxide (CO_2) from paddy soils were 15.2,16.9, and 36.6 % lower following application of straw + steel slag, straw -(-silicon, and straw + gypsum, respectively, and cumulative emissions of methane (CH_4) were 5.0 and 62.1 % lower following application of straw+steel slag and straw + gypsum, respectively. Meanwhile, relative to the addition of straw alone, application of straw+steel slag and straw + gypsum reduced GHG emissions largely due to reductions in CO_2 emissions, further declining the GWP of CO_2 and GHGI. In addition, temperature sensitivity (Q_(10)) of CO_2 emissions was highest following application of straw + silicon and lowest following application of straw+gypsum. There were no treatment effects on mean dissolved porewater concentrations of CO_2, CH_4, or nitrous oxide (N_2O) and soil emissions of CO_2 were negatively correlated with mean dissolved concentrations of CO_2, CH_4, and N_2O. Rice yields were reduced following application of straw + gypsum and unaffected by the other treatments. Thus, relative to the addition of straw alone or control, we suggest the combined application of straw + steel slag may improve the sustain-ability of paddy rice production, because it reduces GWP, while maintaining yields.
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Aquatic ecosystems are globally significant sources of greenhouse gases (GHG) to the atmosphere, offsetting the terrestrial sinks. A one-year field study was carried out in a shallow eutrophic Lake Wuliangsuhai, Inner Mongolia (dr...
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Aquatic ecosystems are globally significant sources of greenhouse gases (GHG) to the atmosphere, offsetting the terrestrial sinks. A one-year field study was carried out in a shallow eutrophic Lake Wuliangsuhai, Inner Mongolia (draining waters from one of the largest irrigation areas in China), to estimate diffusive GHG fluxes and their relative importance in global warming potential (GWP). Our results showed high spatiotemporal variation in dissolved CO2, CH4 and N2O concentrations, while they did not differ significantly between the bottom and surface layers of the shallow waterbody. In general, GHG concentrations and diffusive fluxes were higher in the north part of the lake than in the south. GHG concentrations in the water under the ice were significantly higher than those during the open-water period. Spatial variability of GHG concentrations varied with the bathymetry of the lake. The location of study sites relative to the main inflow and abundance of submerged macrophytes were the main controlling factors of GHG concentrations, as indicated by the consistency of GHG concentrations at the sampling sites, particularly for N2O. The total diffusive GHG emission from Lake Wuliangsuhai was 76.9 ± 5.4 Gg CO2 equivalents yr?1, with CO2, CH4 and N2O contributing 16 %, 83 %, and 1 %, respectively. Overall, the results suggest that shallow lakes in mid-latitude arid areas with cold winters can be potentially important GHG sources. However, those lakes are insufficiently represented in the scientific literature, and therefore they deserve more research attention.
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