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91.
施用高效氮肥对农田N2O的减排效果及经济效益分析   总被引:5,自引:0,他引:5       下载免费PDF全文
收集高效氮肥N2O排放资料,利用整合分析法分析高效氮肥对N2O的减排效果.稳定性氮肥排放的N2O是普通肥料的0.66倍,减排效果显著;包膜缓释氮肥N2O排放量为普通氮肥的0.95倍,无显著减排效果.若将全国范围的普通氮肥替换为稳定性氮肥、且用N量不变时,稳定性氮肥在中国农田的N2O减排潜力均值为1.03×108 kgN/a,碳排放交易收入为16.86亿元/a;根据现有市场上稳定性氮肥的价格,每亩地每季补贴4.9元,碳排放交易收入和稳定性氮肥成本增加量相抵.由于稳定性氮肥能有效提高N利用率,保证农作物吸N总量不变时减少用N量,稳定性肥料N利用率提高8个百分点时,N2O减排经济效益(即碳排放交易收入-稳定性氮肥成本增加量)为94亿元/a.  相似文献   
92.
Lu, Haorong, S. Samuel Li, and Jinsong Guo, 2012. Modeling Monthly Fluctuations in Submersion Area of a Dammed River Reservoir: A Case Study. Journal of the American Water Resources Association (JAWRA) 1‐13. DOI: 10.1111/jawr.12003 Abstract: Fluctuations in water submersion of the Three Gorges Reservoir in China have not been explored in spite of their important implications for shoreline erosion and other undesirable consequences. This article aims to quantify the monthly fluctuations in response to changing hydraulic parameters and regional climatic factors. Flow velocity and water levels distributed along the 609‐km long dammed river reservoir are calculated with a one‐dimensional hydrodynamics model. Evaporation of water from the surface of the reservoir is determined using mass transfer‐based methods. Calculated flow velocities and water levels compare well with field data. We show that the water surface slope decreases with rising water level at the dam, and decreases to almost zero during the winter months of water storage when the downstream water level reaches the normal pool level. The submersion area varies between 830 and 1,070 km2 over the year or over 20% of the reservoir zone will experience the annual cycle of dry land and partial or complete submersion. These fluctuations are of relevance to shoreline management and to the prevention and restoration of shoreline erosion. Evaporation is estimated to fluctuate between 1,240 and 26,110 tons of water per month per kilometer length of reservoir channel; this can possibly affect the hydrological budget of the reservoir region. The simple methodologies discussed in this article can easily be applied to other dammed river reservoirs for submersion estimates.  相似文献   
93.
朱媛媛  刘冰  桂海林  李健军  汪巍 《环境科学》2022,43(8):3966-3976
基于生态环境监测和气象观测数据,分析了2016~2020年京津冀13个城市臭氧(O3)浓度特征,讨论了O3污染高发月份日最高温度(Tmax)、日均地面气压(p)、日均地面相对湿度(RH)和日均地面风速(v)等气象要素对O3-8h浓度和O3-8h超标情况的影响规律,并采用AQI级别预报准确率、O3浓度范围预报准确率和O3级别预报准确率等方法,评估了基于神经网络的O3统计预报效果.结果表明,2016~2020年期间京津冀13城市ρ(O3-8h-90per)分别为157.4、177.2、177.3、190.6和175.6μg·m-3,区域臭氧浓度5a上升了11.6%,2016~2019年期间总体呈波动上升趋势,2020年环比下降;2020年与2016年相比,除北京、张家口和承德略有下降外,其他10个城市ρ(O3-8h-90per)上升了6~45.5μg·m-3.O3-8h月均值呈现"两头低,中间高"现象,ρ(O3-8h)在4~9月的月均值超过了100 μg·m-3,在6月最高,为158.10 μg·m-3.城市O3-8h超标率范围为8.6%~19.2%,97.8%的O3-8h超标情况发生在4~9月.区域尺度上O3-8h浓度与日最高温度相关性最强,当Tmax在25~28℃区间时,所有城市开始出现O3-8h超标.O3-8h浓度与日均地面气压呈负相关关系;当RH在60%以下时,大部分城市O3-8h浓度随相对湿度上升缓慢增长;当RH在61%~70%以上时,大部分城市O3-8h浓度随日均相对湿度上升而下降.O3-8h超标时的地面主导风向主要为偏南风,大部城市O3-8h浓度高值易集中出现在2~3m·s-1及以下低风速区间.OPAQ统计模式提前1~9 d预报相关系数范围为0.72~0.86,AQI级别预报平均准确率为67%~86%,O3-8h浓度范围预报平均准确率为63%~84%.在O3-8h超标情况多发的4~9月,模式对O3轻度污染和O3-8h超标情况提前3 d预报准确率分别为69%和66%,可为O3-8h超标管控提供参考依据.  相似文献   
94.
Environmental Agencies require Decision Support Systems, in order to plan Air Quality Policies considering the cost of emission reduction measures and the human health effects (with related social costs). The use of Decision Support Systems is also useful to spread information to general public, explaining the effectiveness of proposed air quality plans. In this paper, a multi-objective approach to control PM10 concentration at a regional level is presented. The problem considers both the internal costs (due to the implementation of emission reduction measures) and the external costs (due to population exposure to high PM10 concentrations). To model PM10 concentrations, a single surrogate model is used for the entire domain, allowing the implementation of a very efficient optimization procedure. The surrogate model is derived through a set of 10 simulations, performed using a Chemistry Transport Model fed with different emission reduction scenarios. The methodology is applied to Northern Italy, a region affected by very high PM10 concentrations that exceed the limit values specified by the EU legislation.  相似文献   
95.
Using Japanese facility-level data from an OECD survey, we estimate the effects of implementation of ISO14001 and publication of environmental reports on the facilities’ environmental performance. While most previous studies focused on an index of emissions toxicity, this study examines three areas of impacts, none of which have been explored in the literature: natural resource use, solid waste generation, and wastewater effluent. The study is also unique in that the effectiveness of ISO14001 is considered in relation to environmental regulations. Our findings are summarized as follows. First, both ISO14001 and report publication help reduce all three impacts; the former appears more effective in all areas except wastewater. Second, environmental regulations do not weaken the effect of ISO14001. Third, assistance programs offered by local governments—a voluntary approach—promote facilities’ adoption of ISO14001. These findings suggest that governments can use command-and-control and voluntary approaches concurrently.  相似文献   
96.
Science, politics and environmental policy have for several years been encountering social and institutional as well as scientific challenges, national and international. The normative basis of all sciences is pressurised from three sides: by awareness of the public, who claims more transparency and sensibility from the scientific institutions regarding factual or possible impacts of science-based industrial progress; by the industries, which try to speed up and intensify the industrialisation of knowledge; and by the public policies, which want to see the sciences engaged in ways to mitigate unintended consequences of economic, ecological and social developments. At the same time, environmental policy is undergoing a tremendous sea change both in conceptual and practical matters. Since the Brundtland Report in 1987 and accelerated after UNCED 1992, environmental policy has been struggling to become a groundbreaking new paradigm for the capacity of resolving social and political issues as well. Any successful attempt to alter traditional institutional and mental structures in policy-making toward sustainability presupposes a renewed association of co-operation, deliberation and decision making. Results from theory of democracy, studies in science and technology, and evaluation studies in environmental policy and politics can be utilised for this context.  相似文献   
97.
This study analyses the general-equilibrium impacts of an international climate change response policy on the economy of Western Australia (WA), one of the most mining-based and energy-intensive states of Australia. It finds that emissions would fall by up to 11% from the base level in WA. However, such environmental benefits emanate at some costs to the state economy; in terms of foregone gross state product, the costs are up to 3% of the base level. Indeed, the actual costs and benefits depend on the precise design of the climate change response policy as well as on the other policies within which it operates. For example, when emission quota permits are sold to industries and no tradeable carbon credits (i.e. credits for the carbon sequestrated in Kyoto forests) are granted, emissions decline by about 8% and GSP falls by about 3% of the base levels. If carbon credits are tradeable, however, the environmental benefits could be increased and the GSP cost could be reduced substantially. Also, the reduced economic activity caused by emission abatement results in a modest fall in net government revenue, despite the additional revenue from permit sales in some cases. Accordingly, government’s fiscal package surrounding the emission permits would influence the emission abatement impacts on the economy. With regard to the effects on the structure of the state economy, the oil and gas industry suffers only a slight contraction but the energy-supplying sector as a whole contracts substantially. It is therefore not surprising that the impacts on the WA economy of curbing emissions by energy and transport industries alone are quite significant when compared to those resulted from all industries’ compliance with the abatement scheme. It needs to be noted that the model projections analysed in the paper are based on simplifying assumptions and tentative scenarios, and hence should be viewed with caution and not be understood as unconditional forecasts.  相似文献   
98.
Sound is considered as a pollutant when it exceeds undesirable limits for the recipient. One of the significant environmental problems associated with industries is noise pollution generated by machinery. The main objectives of this study were to measure noise levels generated by machinery that the workers were exposed to at five industrial facilities in the State of Kuwait. Also, to assess if these levels were within acceptable standards, for Kuwait lacks environmental standards for such a pollutant. To achieve the objectives of the study two food manufacturing companies, a cement-brick making plant, a furniture factory and a car washing facility were selected for the purpose of the research.The study showed that workers operating machinery at the five facilities were exposed to high noise levels without any kind of ear protection. Noise levels recorded during the study were very high and exceeded the British Noise at Work Regulations of 1989. In Kuwait there are no regulations to abate noise in the working environment and workers are not required to wear ear protective muffs. The results of the study indicate that, the concerned environmental and health organisations in Kuwait should be compelled to establish noise level standards and controls to safeguard the health of workers and the public at large.  相似文献   
99.
马仕君  周传斌  杨光  赵志岚  刘懿颉 《环境科学》2019,40(12):5593-5603
填埋场中的生活垃圾成分复杂,即使在封场后其存量垃圾仍将持续产生温室气体、恶臭、地下水污染等环境问题,是城市生态环境修复的重点领域之一.生活垃圾填埋场物质存量、组成成分和理化特征是掌握其潜在环境影响的关键.但是目前关于填埋场物质存量及其环境影响的研究还不多见.本研究以我国城市化程度最高、人口最为密集的粤港澳大湾区城市群为例,基于国内外报道的科技信息和统计数据,对11个城市的生活垃圾产生量、处理量、组成成分、填埋场存量及关键元素碳存量进行分析.结果表明:①粤港澳大湾区2017年生活垃圾产生量为26. 4 Tg,平均每年增长0. 8 Tg,其中卫生填埋处置占58. 9%;②总生活垃圾填埋处置量为230. 1 Tg,其中食物、塑料和纸类垃圾的累计填埋处置量最多,分别为109. 6、38. 9和29. 6 Tg;③2001~2017年,大湾区城市生活垃圾填埋场总碳输入量为50. 0 Tg,通过填埋气排放的碳为7. 1 Tg,通过渗滤液排放的碳为1. 5 Tg,累积碳存量为41. 4 Tg.本研究可为研究城市生活垃圾填埋场的环境影响提供基础数据,为大湾区城市生态环境修复提供科学依据.  相似文献   
100.
Only recently, studies of forest succession have started to include the effects of browsing by wild or domestic ungulates. We aim to contribute to this topic by analysing the influence of goat grazing on the long-term coexistence of Scots pine (Pinus sylvestris L.) and pubescent oak (Quercus pubescens Willd.) in the low-elevation forests of an inner-Alpine dry valley. The forest gap model ForClim was first adapted to these site conditions by examining the site-dependent sensitivity of the model with regard to the species-specific parameterisation of the drought tolerance as well as the light demand of establishing and adult trees. In a second step, the behaviour of the model was investigated with respect to different grazing intensities and species-specific browsing susceptibilities. The last step was the application of a grazing scenario based on forest history, with 150 years of heavy browsing (by goats) at the beginning of the simulated forest succession, followed by less intensive grazing pressure.  相似文献   
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