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941.
根据收集的青岛市九大类排放源的活动水平数据,本研究采用排放因子法结合调研实测等工作建立了青岛市VOCs源排放清单,结果表明,工业企业VOCs排放占总排放的比例达到43.17%。其中,工艺过程源类中排放占比较高的行业依次为橡胶和塑料制品业、非金属矿物制品业、原油加工及石油制品制造业、化学原料和化学制品制造业、黑色金属冶炼和压延加工业等;溶剂使用源类中排放占比较高的行业为金属制品业、皮革皮毛羽毛制品和制鞋业、印刷业、铁路船舶航空等设备制造业、汽车制造业等。通过对重点行业重点企业进行入场调研采样分析,本研究发现不同行业中VOCs组成特征有差异,多数行业VOCs物种排放以卤代烃、芳香烃、烷烃等为主,纺织印染业、制鞋业等部分行业以含氧有机物排放为主。通过调研和实测对部分行业的VOCs排放因子水平做了本地化深入研究,调研统计青岛市约49%的企业安装了VOCs治理设施;在企业所安装的VOCs治理设施中吸附法占比最大,占比为26%。  相似文献   
942.
外源稀土在土壤中各形态的动态变化   总被引:9,自引:3,他引:6  
在小麦整个生长期内定期测定外源稀土进入土壤后各形态稀土随时间的变化,结果为:外源稀土进入土壤后可交换态稀土含量随时间的延长显著降低,减少的可交换态稀土一部分被小麦吸收,一部分被土壤所吸附,其中在分蘖期减少得最快;根系的分泌活动明显影响土壤中稀土元素的存在形态,铁锰氧化物结合态稀土含量在拔节期前逐渐增加,拔节期后略有下降;碳酸盐结合态稀土含量随时间的延长而降低,但下降幅度较小;有机物结合态与残渣态稀土含量随时间的延长没有发现明显的变化.  相似文献   
943.
The impact of large-scale urban development on land resources has long been debated by urban planners and designers. This study investigated the extent to which different urban characteristics are associated with land-cover change. The Yangtze River Delta region in China, forming one of the largest sprawling urban landscapes among the regions around the world, was chosen for the study area. Spatial analysis and multiple regression methods were applied to empirically investigate the pattern of resource sites lost to urban development in the area between the 1950s and 2017. The results showed that contrary to the widespread notion that large-sized cities are predominantly responsible for a region’s environmental degradation, city size was not a significant factor in determining the rate of resource loss. Large-sized cities gained their populations with far lesser impacts on land than small-sized cities and towns if normalized to the same number of populations. One explanation for the diminishing effect of city size on land-cover change relates to the degree of spatial dispersion of urban development and local differences in social valuation of diversified lands by cities.  相似文献   
944.
We exploit recent advances in climate science to develop a physically consistent, yet surprisingly simple, model of climate policy. It seems that key economic models have greatly overestimated the delay between carbon emissions and warming, and ignored the saturation of carbon sinks that takes place when the atmospheric concentration of carbon dioxide rises. This has important implications for climate policy. If carbon emissions are abated, damages are avoided almost immediately. Therefore it is optimal to reduce emissions significantly in the near term and bring about a slow transition to optimal peak warming, even if optimal steady-state/peak warming is high. The optimal carbon price should start relatively high and grow relatively fast.  相似文献   
945.
This paper examines the effects of extreme temperatures on mortality rates, using random year-to-year variation in temperature based on county-level panel data from China. The analysis finds a robust, U-shaped relationship between temperature and mortality rates, indicating that extremely cold or hot temperatures lead to excess deaths. The heat-related (cold-related) effect is 3.5 times (3.2 times) as large as previous findings that used U.S. data, and it is especially large for the elderly population, mainly due to excess deaths caused by cardiovascular diseases. Applying these results to climate change predictions from Hadley Centre Global Environmental Model shows that by 2061–2080 the annual mortality rate is likely to increase by 14.2% if global greenhouse gas emissions continue to rise throughout the 21st century, the estimated health cost of which is around 0.98 trillion Chinese Yuan per year. The paper also explores households’ adaptation behaviors to extreme temperatures. It finds that although urban households adaptively increase energy consumption when they are exposed to cold temperatures and purchase more air conditioners on hot and cold days, rural households are unresponsive to temperature fluctuations. This finding implies that rural people may be more resource constrained and suffer more when extreme temperatures occur.  相似文献   
946.
We analyze the effect of CEO education on environmental decision-making. Using a unique sample of Danish firms from 1996 to 2012, we find that CEO education significantly improves firms' energy efficiency. We seek to derive causality using health shocks: the hospitalization of highly educated CEOs induces a drop in energy efficiency, whereas the hospitalization of less educated CEOs does not have any significant effect. Exploring the mechanisms at play, we show that our results are largely driven by advanced education in business degrees. Moreover, we show that CEO education is associated with greater environmental awareness: highly educated CEOs exhibit greater concerns for climate change, as measured by a survey of social preferences, and drive more environmentally efficient cars. Taken together, our findings suggest that education shapes managerial styles giving rise to greater sustainability in corporate actions.  相似文献   
947.
根据国际上对于荒漠化概念的新说明以及由联合国环境规划署所资助的《中国荒漠化 (土地退化 )防治研究》课题报告中确定的荒漠化定义 ,荒漠化概念的内涵包括 :1)以土地退化为本质 ;2 )与人类活动相关联 ;3)以荒漠化景观为标志 ;4 )以脆弱生态环境为背景。因此我国的荒漠化类型除了风蚀作用形成的沙质荒漠化外 ,还有水蚀作用形成的土质荒漠化和石质荒漠化 ;荒漠化防治的重点区域除北方干旱、半干旱和半湿润地区以外 ,也包括南方湿润地区的红壤丘陵区和石质山区。其中属于水蚀荒漠化和土质荒漠化的红色荒漠化就是指我国南方红壤丘陵区在人类不合理经济活动和脆弱生态环境相互作用背景下 ,以流水侵蚀为主导作用而形成、以地表出现劣地为标志的严重土地退化。鉴于我国南方红色荒漠化现象在我国现实存在中的客观性、在全球变化中的特殊性以及在理论概念上的模糊性 ,有必要对其进行深入研究  相似文献   
948.
The High Plains aquifer (HPA) is the primary water source for agricultural irrigation in the US Great Plains. The water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds recharge, which has been a serious concern to the water resources management in the region. We evaluated temporal trends and variations in agricultural water use and hydroclimatic variables including precipitation, air temperature, reference evapotranspiration, runoff, groundwater level, and terrestrial water storage across the HPA region for different periods from 1985 to 2020 at the grid, county, or region scale. The results showed that water withdrawals decreased from 21.3 km3/year in 1985 to 18.2 km3/year in 2015, while irrigated croplands increased from 71,928 km2 in 1985 to 78,464 km2 in 2015 in the entire HPA. The hydroclimatic time-series showed wetting trends in most of the northern HPA, but drying and warming trends in the southern region from 1985 to 2020. The groundwater level time-series indicated flat trends in the north, but significant declining in the central and southern HPA. Trends in irrigation water withdrawals and irrigation area across the HPA were controlled by the advancement of irrigation systems and technologies and the management of sustainable water use, but also were affected by dynamical changes in the hydroclimatic conditions.  相似文献   
949.
Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
950.
We study the effect of potentially severe climate change on optimal climate change policy, accounting for learning and uncertainty in the climate system. In particular, we test how fat upper tailed uncertainty over the temperature change from a doubling of greenhouse gases (the climate sensitivity), affects economic growth and emissions policy. In addition, we examine whether and how fast uncertainties could be diminished through Bayesian learning. Our results indicate that while overall learning is slow, the mass of the fat tail diminishes quickly, since observations near the mean provide evidence against fat tails. We denote as “tail learning” the case where the planner rejects high values of the climate sensitivity with high confidence, even though significant uncertainty remains. Fat tailed uncertainty without learning reduces current emissions by 38% relative to certainty, indicating significant climate insurance, or paying to limit emissions today to reduce the risk of very high temperature changes, is optimal. However, learning reduces climate insurance by about 50%. The optimal abatement policy is strongly influenced by the current state of knowledge, even though greenhouse gas (GHG) emissions are difficult to reverse. Once the mass of the fat tail diminishes, the remaining uncertainty is largely irrelevant for optimal emissions policy.  相似文献   
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