中国主要农作物种植农药施用温室气体排放估算

Ratoon rice can improve rice yield by increasing the multiple cropping index in China. However, the greenhouse gas (CH4 and N2O) emission characteristics from ratoon rice fields and the cultivation methods to reduce CH4 and N2O emissions are rarely reported. This study first conducted the analysis of genotype differences in greenhouse gas emission fluxes using five strong ratoon ability rice varieties in 2020. Second, water management methods, including alternating the wet–dry irrigation (AWD) pattern and conventional flooding irrigation (CF) during the main season, were carried out in 2021. CH4 and N2O emission flux, agronomic traits, and rice yield during both main and ratoon seasons were investigated. The results showed that the CH4 emission flux during the main and ratoon seasons was 157.05–470.73 kg·ha–1 and 31.03–84.38 kg·ha–1, respectively, and the total N2O emission flux was 0.13–0.94 kg·ha–1 in the ratoon rice system over the two seasons (RRSTS). Compared with the main season, the CH4 emission flux during the ratoon season was significantly reduced, thus decreasing the greenhouse gas global warming potential (GWP) and greenhouse gas emission intensity (GHGI) in the ratoon rice system. Cliangyouhuazhan (CLYHZ) showed a high yield, and the lowest GWP and GHGI values among the five rice varieties in RRSTS. Compared with CF, the AWD pattern reduced the CH4 emission flux during the main and ratoon seasons by 67.4–95.3 kg·ha–1 and 1.7–5.1 kg·ha–1, respectively, but increased the N2O emission flux by 0.1–0.6 kg·ha–1 during the RRSTS. Further, compared with CF, the AWD pattern had a declined GWP by 14.3–19.4% and GHGI by 30.3–34.3% during the RRSTS, which was attributed to the significant reduction in GWP and GHGI during the main season. The AWD pattern significantly increased rice yield by 21.9–22.9% during the RRSTS, especially for YX203. Correlation analysis showed that CH4, GWP, and GHGI exhibited significant negative correlations with spikelet number per m2 and the harvest index during the main and ratoon seasons. Collectively, selecting the high-yield, low-emission variety CLYHZ could significantly reduce greenhouse gas emissions from ratoon rice while maintaining a high yield. The AWD pattern could reduce total CH4 emission during the main season, reducing the GWP and GHGI while increasing the ratoon rice system yield. It could be concluded that a variety of CLYHZ and AWD patterns are worthy of promotion and application to decrease greenhouse gas emissions in the ratoon rice area in the upper reaches of Yangtze River, China.

Change in carbon footprint of canola production in the Canadian Prairies from 1986 to 2006

Life cycle assessment of sludge anaerobic digestion combined with land application treatment route: Greenhouse gas emission and reduction potential

Carbon footprint of renewable diesel from palm oil, jatropha oil and rapeseed oil

Intensive cultivation and post-harvest vegetable oil production stages are major sources of greenhouse gas (GHG) emissions. Variation between production systems and reporting disparity have resulted in discordance in previous emissions estimates. The aim of this study was to assess global systems-wide variation in GHG emissions resulting from palm, soybean, rapeseed and sunflower oil production. Such an analysis is critical to understand the implications of meeting increasing edible oil demand. To achieve this, we performed a unified re-analysis of life cycle input data from diverse palm, soybean, rapeseed, and sunflower oil production systems, from a saturating search of published literature. The resulting dataset reflects almost 6000 producers in 38 countries, and is representative of over 71% of global vegetable oil production. Across all oil crop systems, median GHG emissions were 3.81 kg CO2e per kg refined oil. Crop specific median emissions ranged from 2.49 kg CO2e for rapeseed oil to 4.25 kg CO2e for soybean oil per kg refined oil. Determination of the carbon cost of agricultural land occupation revealed that carbon storage potential in native compared to agricultural land cover drives variation in production GHG emissions, and indicates that expansion of production in low carbon storage potential land, whilst reforesting areas of high carbon storage potential, could reduce net GHG emissions whilst boosting productivity. Nevertheless, there remains considerable scope to improve sustainability within current production systems, including through increasing yields whilst limiting application of inputs with high carbon footprints, and in the case of palm oil through more widespread adoption of methane capture technologies in processing stages.

In this paper the benefits of rapeseed oil (RO) replacing petroleum diesel in transportation are evaluated, demonstrating that RO use displaces greenhouse gas (GHG) emissions and saves fossil energy. A systemic description of the RO chain in France has been implemented and GHG emissions and energy used throughout the life cycle have been calculated using alternative co-product credit procedures, namely a replacement method, three allocation approaches (mass, energy, economic) and ignoring co-product credits. The results show that the cultivation stage is particularly important, being responsible for 68% of the primary energy requirements and 87% of the GHG emissions of the RO “well-to-tank” system, mainly due to the use of fertilizers and related N2O emissions. Considerable reductions in fossil fuel depletion and GHG emissions can be achieved by replacing petroleum diesel with rapeseed oil (0.9 MJ and 62 g CO2eq per MJ of fossil diesel replaced), but optimum use of co-products is needed.

Rapeseed (Brassica napus L.) production experienced a considerable increase during the past decades, and there is growing concern about how to realize the dual objectives of meeting the increasing demand for rapeseed and reducing the associated greenhouse gas (GHG) emissions. Most reported studies on crop‐sourced GHG emissions to date were aimed at optimizing crop management to reduce emission, but often without a detailed spatio‐temporal assessment of GHG emissions for layout management practices. Herein, we used a newly developed modelling approach that integrates the NUtrient Flows in food chains, Environment, and Resource use (NUFER) model with a dynamic reactive nitrogen (Nr) loss module for rapeseed and Life Cycle Assessment (LCA) approach to assess the GHG emissions from rapeseed production in China, where produces 18% of the world's rapeseed. Results showed that the GHG emissions from rapeseed production in China increased by 1.90% yearly from 2004 to 2018, largely due to increased inputs of agricultural materials, especially diesel. Further, carbon footprints of rapeseed production were found vary greatly between production regions, due to diverse climatic conditions, field management practices and the level of mechanization. Scenario analysis showed that adoption of both optimized nutrient and layout management practice is required to mitigate the current resource and environmental burdens, and to achieve edible oil security. Thus, our study provides new insights for policymakers on the formulation of management practices to reduce crop‐sourced GHG emissions, going along with an increase of food demand in the future.

Biochar potentially mitigates greenhouse gas emissions from cultivation of oilseed rape for biodiesel

Agriculture plays a role in greenhouse gas (GHG) emissions, especially by cultivating biofuel crops like rapeseed (Brassica napus).This study assesses the GHG emissions associated with rapeseed farming in Romania, focusing on 2022-2024.Data were collected from rapeseed cultivation at Mihai Viteazu, Cluj, under various fertilization and irrigation conditions.The study reveals that GHG emissions range from 89 to 231 kg CO2 eq/l biodiesel, with irrigation reducing emissions by approximately 1.3 times compared to non-irrigated conditions.Notably, nitrogen fertilization significantly increases nitrous oxide (NOx) emissions, which account for 80% of total GHG emissions, particularly under higher nitrogen application rates.The results highlight the need for optimized nitrogen management to balance yield increases with environmental impacts, as excessive nitrogen use intensifies NOx emissions due to enhanced nitrification and denitrification processes.The study also finds that irrigation mitigates GHG and NOx emissions, emphasizing its role in sustainable rapeseed farming.This research underscores the importance of precision nitrogen management and irrigation in reducing the carbon footprint of rapeseed biodiesel production while enhancing crop productivity in Romania.

SummaryThis article evaluates the implications of uncertainty in the life cycle (LC) energy efficiency and greenhouse gas (GHG) emissions of rapeseed oil (RO) as an energy carrier displacing fossil diesel (FD). Uncertainties addressed include parameter uncertainty as well as scenario uncertainty concerning how RO coproduct credits are accounted for (uncertainty due to modeling choices). We have carried out an extensive data collection to build an LC inventory accounting for parameter uncertainty. Different approaches for carbon stock changes associated with converting set‐aside land to rapeseed cultivation have been considered, which result in different values: from −0.25 t C/ha.yr (carbon uptake by the soil in tonnes per hectare year) to 0.60 t C/ha.yr (carbon emission). Energy renewability efficiency and GHG emissions of RO are presented, which show the influence of parameter versus scenario uncertainty. Primary energy savings and avoided GHG emissions when RO displaces FD have also been calculated: Avoided GHG emissions show considerably higher uncertainty than energy savings, mainly due to land use (nitrous oxide emissions from soil) and land use conversion (carbon stock changes). Results demonstrate the relevance of applying uncertainty approaches; emphasize the need to reduce uncertainty in the environmental life cycle modeling, particularly GHG emissions calculation; and show the importance of integrating uncertainty into the interpretation of results.

Greenhouse gases (GHG) emissions analysis of manufacturing of the hydraulic press slider within forging machine in China

The potential challenge for the effective GHG emissions mitigation of urban energy consumption: A case study of Macau

PDF HTML阅读 XML下载 导出引用 引用提醒 中国氮磷钾肥制造温室气体排放系数的估算 DOI: 10.5846/stxb201402210304 作者: 作者单位: 中国科学院生态环境研究中心,中国科学院生态环境研究中心,中国科学院生态环境研究中心 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金青年基金项目(71003092);科技部973专题项目(2010CB833504-2);中国科学院战略性先导科技专项子课题(XDA05050602, XDA05060102) Estimation of greenhouse gases emission factors for China's nitrogen, phosphate, and potash fertilizers Author: Affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences,,Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:通过收集、整合国内相关数据,推算了符合中国目前情况的各种氮肥、磷肥和钾肥的制造过程中的温室气体排放系数(从原料到工厂大门)。结果显示,我国平均水平的氮肥制造碳排放系数为:合成氨(液氨)1.672 t CE/t N,尿素2.041 t CE/t N,碳铵1.928 t CE/t N,硝酸铵4.202 t CE/t N,氯化铵2.220 t CE/t N,氮肥综合系数为2.116 t CE/t N。我国一般水平的磷肥制造碳排放系数为:重钙0.467 t CE/t P2O5,磷酸二铵1.109 t CE/t P2O5,磷酸一铵0.740 t CE/t P2O5,普钙0.195 t CE/t P2O5,钙镁磷肥2.105 t CE/t P2O5,磷肥综合系数为0.636 t CE/t P2O5。我国先进水平的钾肥制造碳排放系数为:氯化钾0.168 t CE/t K2O,硫酸钾0.409 t CE/t K2O(其中罗钾法硫酸钾0.443 t CE/t K2O、曼海姆法硫酸钾0.375 t CE/t K2O),钾肥综合系数为0.180 t CE/t K2O。我国大部分氮磷钾肥的温室气体排放系数普遍为欧美平均水平的2倍左右,因此利用国外系数来估算我国的农业温室气体排放量将严重低估化肥施用的影响。 Abstract:As fossil fuel based chemical products, synthetic fertilizers are highly energy-intensive and therefore highly carbon-intensive products as well. Fertilizers are one of the most important modern agricultural materials for enhancing crop yields. The manufacture of fertilizers is also a considerable indirect greenhouse gases (GHGs) emission source related to agricultural activities. To feed its huge population, China has raised its average fertilizer application level from 86.7 kg/hm2 in 1980 to 346.1 kg/hm2 in 2010 (total N, P2O5 and K2O). China has been the largest fertilizer producer and consumer worldwide for ten years, and its fertilizer consumption has exceeded 4.76 ×107 t, almost one third of the world's total, since 2005. Thus, it is essential to evaluate the GHGs emission related to the production and consumption of synthetic fertilizers in China. However, most current Life-Cycle Analysis (LCA) studies on China's agricultural GHGs emission use foreign fertilizer emission factors (GHGs per unit of fertilizer product) because the actual domestic factors were not available, which might result in significant miscalculations and uncertainties. To solve this problem, we collected data specific to China's fertilizer manufacture and consumption, and then estimated GHGs emission factors for several types of nitrogen, phosphate, potash and compound fertilizer currently in use in China. These fertilizers were: ammonia, urea, ammonium bicarbonate(AB), ammonium nitrate(AN), ammonia chloride(AC), general nitrogen fertilizer (General-N), triple superphosphate (TSP), monoammonium phosphate (DAP), monoammonium phosphate (MAP), superphosphate (SSP), fused calcium magnesium phosphate (FCMP), general phosphate fertilizer (General-P), potassium chloride (PC), general potassium sulphate (PS), Lop-Lake-method potassium sulphate (PS-LopLake), (PS-Mannheim) and general potash fertilizer (General-K). Our emission factors accounted for CO2, CH4 and N2O released not only during manufacturing, but also from feedstock production and transportation outside factories (i.e. "from cradle to factory gate"). Due to the availability of different data, emission factors for N/P/K fertilizers were calculated using different methods, and thus represent different technological scenarios (N fertilizers: China's current average technical level. P fertilizers: China's current ordinary technological level, slightly behind the "average level", representing the nation's target for energy-saving. K fertilizers: China's current advanced technological level, representing the best potash factories with highest energy efficiency in China). China's average-level nitrogen fertilizer manufacturing GHGs emission factors were: ammonia 1.672 t CE/t N, urea 2.041 t CE/t N, AB 1.928 t CE/t N, AN 4.202 t CE/t N, AC 2.220 t CE/t N and General-N 2.116 t CE/t N. China's ordinary-level phosphate fertilizer manufacturing GHGs emission factors were: TSP 0.467 t CE/t P2O5, DAP 1.109 t CE/t P2O5, MAP 0.740 t CE/t P2O5, SSP 0.195 t CE/t P2O5, FCMP 2.105 t CE/t P2O5 and General-P 0.636 t CE/t P2O5. China's advanced-level potash fertilizer manufacturing GHGs emission factors were: PC 0.168 t CE/t K2O, PS 0.409 t CE/t K2O, PS-LopLake 0.443 t CE/t K2O, PS-Mannheim 0.375 t CE/t K2O and General-K 0.180 t CE/t K2O. As a result of the more complete LCA chain investigated in this study, different natural resource availability and distribution traits, energy structure, and technological levels, most fertilizers' GHGs emission factors in China were about 2-fold of those in western countries. Thus, the models using western factors to calculate China's agricultural GHGs emissions will significantly underestimate the impact of fertilizer application. 参考文献 相似文献 引证文献

Greenhouse gas emissions and mitigation strategies in China's municipal solid waste sector under the impact of the COVID-19 pandemic

Wastewater treatment plants (WWTPs) have been recognized as important sources for anthropogenic greenhouse gas (GHG) emission. The objective of the study was to thoroughly investigate a typical industrial WWTP in southern Taiwan in winter and summer which possesses the emission factors close to those reported values, with the analyses of emission factors, mass fluxes, fugacity, lab-scale in situ experiments, and impact assessment. The activated sludge was the important source in winter and summer, and nitrous oxide (N2O) was the main contributor (e.g., 57 to 91% of total GHG emission in a unit of kg carbon dioxide-equivalent/kg chemical oxygen demand). Albeit important for the GHGs in the atmosphere, the fractional contribution of the GHG emission to the carbon or nitrogen removal in wastewater treatment was negligible (e.g., less than 1.5%). In comparison with the sludge concentration or retention time, adjusting the aeration rate was more effective to diminish the GHG emission in the activated sludge without significantly affecting the treated water quality. When the aeration rate in the activated sludge simulation was reduced by 75%, the mass flux of N2O could be diminished by up to 53% (from 9.6 to 4.5mg/m2-day). The total emission in the WWTP (including carbon dioxide, methane, and N2O) would decrease by 46% (from 0.67 to 0.36kg CO2-equiv/kg COD). However, the more important benefit of changing the aeration rate was lowering the energy consumption in operation of the WWTP, as the fractional contribution of pumping to the total emission from the WWTP ranged from 46 to 93% within the range of the aeration rate tested. Under the circumstance in which reducing the burden of climate change is a global campaign, the findings provide insight regarding the GHG emission from treatment of industrial wastewater and the associated impact on the treatment performance and possible mitigation strategies by operational modifications.