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321.
There is a widely acknowledged need for a single composite index that provides a comprehensive picture of the societal impact of disasters. A composite index combines and logically organizes important information policy‐makers need to allocate resources for the recovery from natural disasters; it can also inform hazard mitigation strategies. This paper develops a Disaster Impact Index (DII) to gauge the societal impact of disasters on the basis of the changes in individuals’ capabilities. The DII can be interpreted as the disaster impact per capita. Capabilities are dimensions of individual well‐being and refer to the genuine opportunities individuals have to achieve valuable states and activities (such as being adequately nourished or being mobile). After discussing the steps required to construct the DII, this article computes and compares the DIIs for two earthquakes of similar magnitude in two societies at different levels of development and of two disasters (earthquake and wind storm) in the same society.  相似文献   
322.
用“土壤养分状况系统研究法”对粤东8 片龙眼园土壤进行大、中、微量营养元素含量测定、土壤吸附试验及盆栽诊断试验。结果表明,全部供试土壤均缺 N 和 P,88 % 土壤缺 K 和 Mg ,75 % 土壤缺 Ca 和 S,63 % 土壤缺 Cu ,50 % 土壤缺 B。在缺素土壤中若不配施这些元素,指示作物( 高粱) 的干物产量分别下降 N 60 .3 % , P65 .3 % , K 29 .5 % , Ca 46 .2 % , Mg 33 .5 % , Cu 19 .3 % , S17 .9 % , B15 .5 % 。综合各营养元素的施肥效应及缺乏的普遍性显示,粤东龙眼立地土壤养分限制因子排序为: N > P> Mg > K > Ca > Cu > S> B;碱性紫色土则富 Ca 。  相似文献   
323.
In the habitat of desert ants, Cataglyphis fortis, a constant wind is usually blowing during the daytime. When visiting a familiar food source, the ants steer some distance downwind of the feeder, rather than attempting a direct approach that might miss small food sources, in particular. In the downwind area, the ants pick up the odor plume emanating from the food and follow it upwind to the prey. This strategy saves considerable walking distance and time. The additional path necessitated by the downwind strategy is only about 0.75 to 2 m, depending on nest–feeder distance, while missing the food on the upwind side results in much longer search trajectories. During the initial three to five visits to a feeding site, downwind distance and length of the approach path are shortened notably, and the approach trajectory is straightened. Desert ants further exhibit considerable short-term flexibility in their approach. Experienced individuals are evidently able to decide upon leaving the nest which direction to choose toward the feeder, depending on current wind direction (that fluctuates slightly during the day). Notable changes in wind direction occur primarily overnight. For larger nest–feeder distances, the animals adjust their approach en route to the altered wind direction during their first foraging trip in the morning.  相似文献   
324.
我国大气污染形势严峻,科学合理地评估大气污染的经济损失不仅有益于政策效益分析,同时是“绿色国民经济”核算的一项基础性工作。基于我国2013年2月到2018年7月的区县月度房屋交易数据和7种大气污染指标(AQI、SO2、NO2、CO、O3、PM10、PM2.5)的浓度数据,运用特征价格模型实证量化大气污染物减少的边际支付意愿(MWTP)和总经济损失。首先通过改变理性预期的时间段验证理性预期假设的成立,在此基础上采用理性预期方法解决遗漏变量所导致的内生性问题。研究结果显示:①NO2、CO、PM2.5和PM10每上升1μg/m3,房价分别降低约2.04%、0.028%、0.34%和0.39%;而SO2与O3对房价的影响并不显著。②近年来大气污染的经济损失有所降低,政府的治理效果显著,但仍不容小觑。2013年AQI、PM10和PM2.5未达标导致的经济损失分别约为35600亿元、19300亿元和24100亿元,约占当年GDP的6.06%、3.29%和4.11%;2018年分别降低至19200亿元、5300亿元和6700亿元,占当年GDP的2.14%、0.60%和0.74%。尽管PM10和PM2.5浓度也在逐年下降,但仍未达到《环境空气质量标准》所要求的二级限值。最终评估结果显示,PM10和PM2.5二者导致的经济损失的加总数值,与AQI得到的数值相差无异。进一步证实了我国当前大气污染导致的社会经济福利损失主要是来自PM10和PM2.5的超标,因此治理“雾霾”是改善当前空气质量的关键。  相似文献   
325.
选取川南页岩气区块为研究对象,运用过程生命周期评估和投入产出生命周期方法核算页岩气开采生命周期的直接和间接用水量,并与美国Marcellus页岩气区块用水量进行比较。川南区块总直接用水量为22 928 m^3/井,高于Marcellus区块的总直接用水量15 320 m^3/井。从生命周期阶段来看,川南页岩气开采钻井和压裂阶段的直接用水均远大于Marcellus区块。结合水环境管理指标,自然资源禀赋条件主要决定了直接用水量的差异。川南区块总间接用水量为25 098 m^3/井,超过总直接用水量,约为Marcellus区块总间接用水量的3倍。除井场准备阶段外,其余阶段的间接用水量均大于Marcellus区块,间接用水量的差异与钻井和压裂过程的添加剂、能源使用量和全行业用水效率有关。减少川南区块页岩气开发用水量的主要途径包括提高钻井液和压裂液回用率、改善钻井和压裂添加剂使用效率、提高柴油和电力等能源利用效率和全行业用水效率。  相似文献   
326.
对亚甲蓝分光光度法进行改进,用固体试剂快速测定水中的阴离子表面活性剂。在最大吸收波长652nm处,阴离子表面活性剂质量浓度为0~2.0m g/L时遵守比尔定律,表观摩尔吸光系数为1.56×104L/(m o.lcm),检出限为0.03m g/L。该方法用于自来水、河水和工业废水中阴离子表面活性剂的测定,取得了满意结果。环境水样的平均回收率为88.3%~108.0%,相对标准偏差不超过4.67%。  相似文献   
327.
Private forest owners are the main forest ownership group within Europe, and important conservation values have been found on their land. Yet, small plot sizes, societal heterogeneity, and structural changes impede developing and implementing effective conservation programs in private forests. We present a systematic literature review focusing on small-scale private forest owners and their perspectives on nature conservation by synthesizing research approaches, social-ecological drivers, and policy recommendations. Conservation perspectives were positively related to female gender, higher levels of education, formalized forest management, an active relation to the forest, and ecological values of the property. In contrast, high age, rural orientation, economic forest management factors, large parcel size, and economic and sentimental property values negatively influenced conservation perspectives. Applying a natural resource conflict management framework, we synthesized recommendations covering three dimensions: substance, procedure, relationship. Considering perspectives of small-scale private forest owners in current forestry decision-making has great potential to strengthen sustainable forest management that integrates nature conservation and resource use.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01615-w.  相似文献   
328.
全国及重点区域臭氧污染现状   总被引:2,自引:0,他引:2  
分析2013—2016年中国开展臭氧(O_3)监测的338个城市(港、澳、台不在统计范围)O_3污染现状和时空变化特征,结果表明:中国城市O_3污染日益突出,2015年54个城市O_3超标,75.9%的O_3超标城市位于京津冀及周边、长三角、珠三角区域,O_3区域污染特征显著。74个城市O_3浓度整体呈上升趋势并向高值区集中,京津冀区域O_3污染最为严重。O_3污染季节变化特征明显,O_3污染主要集中于5—10月,京津冀、长三角和珠三角区域O_3最高超标天数分别出现在6、5、10月。建议加强O_3成因分析,建立O_3污染控制策略,有效应对O_3污染,实现科学减排。  相似文献   
329.
We introduce climate impact response functions as a means for summarizing and visualizing the responses of climate-sensitive sectors to changes in fundamental drivers of global climate change. In an inverse application, they allow the translation of thresholds for climate change impacts (‘impact guard-rails’) into constraints for climate and atmospheric composition parameters (‘climate windows’). It thus becomes feasible to specify long-term objectives for climate protection with respect to the impacts of climate change instead of crude proxy variables, like the change in global mean temperature. We apply the method to assess impacts on terrestrial ecosystems, using the threat to protected areas as the central impact indicator. Future climate states are characterized by geographically and seasonally explicit climate change patterns for temperature, precipitation and cloud cover, and by their atmospheric CO2 concentration. The patterns are based on the results of coupled general circulation models. We study the sensitivity of the impact indicators and the corresponding climate windows to the spatial coverage of the analysis and to different climate change projections. This enables us to identify the most sensitive biomes and regions, and to determine those factors which significantly influence the results of the impact assessment. Based on the analysis, we conclude that climate impact response functions are a valuable means for the representation of climate change impacts across a wide range of plausible futures. They are particularly useful in integrated assessment models of climate change based on optimizing or inverse approaches where the on-line simulation of climate impacts by sophisticated impact models is infeasible due to their high computational demand. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
330.
The simultaneous accounting of effects of natural and anthropogenic changes within a common framework calls for the development of new comprehensive tools capable of integrating biological processes that span a huge range of scales, from viruses to fishes, in addition to their interactions with physical–chemical environmental properties, i.e. End-to-End models.  相似文献   
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