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91.
The energy sector in Poland is the source of 81% of greenhouse gas (GHG) emissions. Poland, among other European Union countries, occupies a leading position with regard to coal consumption. Polish energy sector actively participates in efforts to reduce GHG emissions to the atmosphere, through a gradual decrease of the share of coal in the fuel mix and development of renewable energy sources. All evidence which completes the knowledge about issues related to GHG emissions is a valuable source of information. The article presents the results of modeling of GHG emissions which are generated by the energy sector in Poland. For a better understanding of the quantitative relationship between total consumption of primary energy and greenhouse gas emission, multiple stepwise regression model was applied. The modeling results of CO2 emissions demonstrate a high relationship (0.97) with the hard coal consumption variable. Adjustment coefficient of the model to actual data is high and equal to 95%. The backward step regression model, in the case of CH4 emission, indicated the presence of hard coal (0.66), peat and fuel wood (0.34), solid waste fuels, as well as other sources (− 0.64) as the most important variables. The adjusted coefficient is suitable and equals R2 = 0.90. For N2O emission modeling the obtained coefficient of determination is low and equal to 43%. A significant variable influencing the amount of N2O emission is the peat and wood fuel consumption. 相似文献
92.
Biological soil disinfestation is an effective method to control soil-borne disease by flooding and incorporating with organic amendments, but field conditions and resources sometimes limited its practical application. A laboratory experiment was conducted to develop practice guidelines on controlling Fusarium wilt, a widespread banana disease caused by Fusarium oxysporum f. sp. cubense (FOC). FOC infested soil incorporated with rice or maize straw at rates of 1.5 tons/ha and 3.0 tons/ha was incubated under flooded or water-saturated (100% water holding capacity) conditions at 30°C for 30 days. Results showed that FOC populations in the soils incorporated with either rice or maize straw rapidly reduced more than 90% in the first 15 days and then fluctuated till the end of incubation, while flooding alone without organic amendment reduced FOC populations slightly. The rapid and dramatic decrease of redox potential (down to − 350 mV) in straw-amended treatments implied that both anaerobic condition and strongly reductive soil condition would contribute to pathogen inactivation. Water-saturation combined with straw amendments had the comparable effects on reduction of FOC, indicating that flooding was not indispensable for inactivating FOC. There was no significant difference in the reduction of FOC observed in the straw amendments at between 1.5 and 3 tons/ha. Therefore, incorporating soil with straw (rice or maize straw) at a rate of 3.0 tons/ha under 100% water holding capacity or 1.5 tons/ha under flooding, would effectively alleviate banana Fusarium wilt caused by FOC after 15-day treating under 30°C. 相似文献
93.
Alicja Kolasa-Wiecek 《环境科学学报(英文版)》2015,27(4):47-54
The energy sector in Poland is the source of 81% of greenhouse gas (GHG) emissions. Poland, among other European Union countries, occupies a leading position with regard to coal consumption. Polish energy sector actively participates in efforts to reduce GHG emissions to the atmosphere, through a gradual decrease of the share of coal in the fuel mix and development of renewable energy sources. All evidence which completes the knowledge about issues related to GHG emissions is a valuable source of information. The article presents the results of modeling of GHG emissions which are generated by the energy sector in Poland. For a better understanding of the quantitative relationship between total consumption of primary energy and greenhouse gas emission, multiple stepwise regression model was applied. The modeling results of CO2 emissions demonstrate a high relationship (0.97) with the hard coal consumption variable. Adjustment coefficient of the model to actual data is high and equal to 95%. The backward step regression model, in the case of CH4 emission, indicated the presence of hard coal (0.66), peat and fuel wood (0.34), solid waste fuels, as well as other sources (-0.64) as the most important variables. The adjusted coefficient is suitable and equals R2 = 0.90. For N2O emission modeling the obtained coefficient of determination is low and equal to 43%. A significant variable influencing the amount of N2O emission is the peat and wood fuel consumption. 相似文献
94.
To assess the responses of the soil microbial community to chronic ozone (O3), wheat seedlings (Triticum aestivum Linn.) were planted in the field and exposed to elevated O3 (eO3) concentration. Three treatments were employed: (1) Control treatment (CK), AOT40 = 0; (2) O3-1, AOT40 = 1.59 ppm•h; (3) O3-2, AOT40 = 9.17 ppm•h. Soil samples were collected for the assessment of microbial biomass C, community-level physiological profiles (CLPPs), and phospholipid fatty acids (PLFAs). EO3 concentration significantly reduced soil microbial carbon and changed microbial CLPPs in rhizosphere soil, but not in non-rhizosphere soil. The results of the PLFAs showed that eO3 concentrations had significant effects on soil community structure in both rhizosphere and non-rhizosphere soils. The relative abundances of fungal and actinomycetous indicator PLFAs decreased in both rhizosphere and non-rhizosphere soils, while those of bacterial PLFAs increased. Thus the results proved that eO3 concentration significantly changed the soil microbial community function and composition, which would influence the soil nutrient supply and carbon dynamics under O3 exposure. 相似文献
95.
温室气体和空气污染物的协同治理是一种双赢的策略。自协同效应的概念提出以来,大量研究对温室气体和大气污染之间的协同减排技术、措施、潜力等方面进行了评估。本研究回顾了协同治理理论的发展历程、典型案例以及重要的政策实践,在此基础上讨论了当前研究与实践的特点,并对未来研究提出了建议。典型案例涉及能源、交通、工业和居民部门,政策实践讨论了温室气体和空气污染协同治理政策的主要类型及其实施情况。从损失评估、协同机理、高精度排放清单及模拟等角度对未来促进协同治理的研究提出了方向建议。 相似文献
96.
环境生态风险评估(ERA)流程已经被纳入全球环境政策中,既用于规范新化学物质的授权和营销(前瞻性环境生态风险评估),也用于评估潜在的污染场地(回顾性环境生态风险评估)。将土壤生态毒理学应用于风险评估,能阐明有毒物质对土壤生态系统中生命有机体的危害程度与范围。笔者主要介绍了应用评估因子法和物种敏感度分布法对基于效应数据进行的外推与估算,并综述了欧美等主要国家和地区的土壤生态风险评估框架、相关法律法规及其实施情况等,为中国开展土壤污染物生态毒理效应和风险评估等相关研究提供参考。 相似文献
97.
98.
Fabio Granados-Chinchilla María de Jesús Arias-Andrés María Laura Fernández Montes de Oca 《Journal of environmental science and health. Part. B》2020,55(2):127-134
AbstractMonensin (MON) is a coccidiostat used as a growth promoter that can reach the environment through fertilization with manure from farm animals. To verify whether field-relevant concentrations of this drug negatively influence the structure and activity of tropical soil bacteria, plate counts, CO2 efflux measurements, phospholipid fatty acids (PLFA) and community-level physiological profiling (CLPP) profiles were obtained for soil microcosms exposed to 1 or 10?mg kg?1 of MON across 11?days. Although 53% (1?mg kg?1) to 40% (10?mg kg?1) of the MON concentrations added to the microcosms dissipated within 5?days, a subtle concentration-dependent decrease in the number of culturable bacteria (<1 log CFU g?1), reduced (?20 to ?30%) or exacerbated (+25%) soil CO2 effluxes, a marked shift of non-bacterial fatty acids, and altered respiration of amines (1.22-fold decrease) and polymers (1.70-fold increase) were noted in some of the treatments. These results suggest that MON quickly killed some microorganisms and that the surviving populations were selected and metabolically stimulated. Consequently, MON should be monitored in agronomic and environmental systems as part of One Health efforts. 相似文献
99.
通过湿法消解土壤样品,利用石墨炉原子吸收分光光度法(GAAS)和火焰原子吸收分光光度法(FAAS)测定不同土壤样品中铅的含量,以验证2种方法的有效性并加以对比。实验结果表明:2种方法均满足土壤中铅含量的测定要求,测定的标准土样含量均在标准值的不确定度范围内,GAAS方法测定结果更接近保证值。二者的相对标准偏差(RSD)值均低于1.5%,FAAS方法的精密度更高,且具有快速简单等优势。 相似文献
100.
石油烃污染场地已经成为国内外重点关注的工业污染场地类型之一。国内基于人体健康风险的污染场地管理模式及分层次评估方法已经展现雏形,为风险管理者提供了基于人体健康的土壤石油烃风险筛选值和管制值,也为污染场地的防治与修复工作提供了决策支持。在前人研究的基础上,梳理了国内土壤环境质量标准体系的建立与发展历程,分析了石油烃类污染物检测方法的现状与未来发展趋势,并着重对比与分析了各标准制订的石油烃及其指示化合物的风险评估筛选值。目前面临的关键问题:①完善石油烃监测指标体系及分析方法是精准获得风险评估结果的前提。现有石油烃馏分指标划分较为宽泛,有必要参考国外先进标准体系,逐渐完善石油烃馏分指标划分及其配套的定量分析方法。②新颁布的国家建设用地土壤污染风险管控标准在前期场地调查中具有一定的普遍适用性,但是考虑到地域建筑物参数、人群暴露参数等的差异性,在后期场地调查中还需要因地制宜地制定适合污染场地的具体修复目标值,并针对关键性参数作定量化解析。 相似文献