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991.
对乌鲁木齐市燃煤点派数量、耗煤量、污染物的排放量以及在各功能区的分布分别进行了统计分析,对污染物的排放量在不同高度空间的分布也进行了统计分析,从而得出了确切的结论并提出了相应的建议。 相似文献
992.
陕西关中渭北地区村镇建筑防火现状调查与分析 总被引:1,自引:0,他引:1
根据相关统计,农村地区建筑面临与城市地区同样的火灾风险。为了农村地区人民生命财产安全,预防火灾,从村镇规划及布局、消防设施及人员消防意识、户舍基本情况调查入手,对陕西关中渭北地区村镇建筑防火现状进行调查与分析。根据调查结果,发现该地区村镇建筑防火条件薄弱,与相关规范差距很大,人员消防意识淡薄,缺乏相关立法规范村镇消防责任制,相关防火规范不完善,应该引起各方对农村防火的高度重视。 相似文献
993.
Md. Mahfuzar Rahman 《中国人口.资源与环境(英文版)》2013,11(4):79-84
Abstract Bangladesh is on target for achieving the Millennium Development Goal 4 relating to infant and under-five mortality because of very rapid reduction in mortality in recent years. But this rate of reduction may be difficult to sustain and may hamper the achievement of Millennium Development Goal 4. Therefore, the main objective of this paper is to discuss and compare the different covariates of infant and under-five mortality in the context of overall country, urban and rural levels of Bangladesh using discriminant analysis. For this, the data are taken from Bangladesh Demographic and Health Survey, 2004. In discriminant analysis, the stepwise procedure has been picked up and only the significant variables are ranked according to the rank of Wilk’s Lambda values. The canonical discriminant function coefficients (unstandardized and standardized) for the predictor variables have also been calculated. Both the results show that breastfeeding is the most important variable in discriminating the two groups of mothers, i.e., mothers experiencing to infant mortality or not and mothers experiencing to under-five mortality or not. The related results of discriminant function also indicate that the discriminant function is statistically significant and discriminates well. Therefore, improvements in the health system are essential for promoting the breastfeeding practices (both inclusive and exclusive), which may be the effective strategies to reach families and communities with targeted messages and information. 相似文献
994.
Jasmin Jaquet Pascal Weitzel Thorsten Junge Burkhard Schmidt 《Journal of environmental science and health. Part. B》2013,48(4):245-254
The metabolic fate of 14C-phenyl-labeled herbicide clodinafop-propargyl (CfP) was studied for 28 days in lab assays using a soil from Germany (Ap horizon, silt loam, and cambisol). Mineralization amounted to 12.40% of applied 14C after 28 days showing a distinct lag phase until day 7 of incubation. Portions of radioactivity extractable by means of 0.01 M CaCl2 solution (bioavailable fraction) decreased rapidly and were 4.41% after 28 days. Even immediately after application, only 57.31% were extracted with the aqueous solvent. Subsequent extraction using accelerated solvent extraction (ASE; acetonitrile/water 4:1, v/v) released 39.91% of applied 14C with day 0 and 26.16% with day 28 of incubation from the samples. Non-extractable portions of radioactivity thus, increased with time amounting to 11.99% (day 0) and 65.00% (day 28). A remarkable increase was observed between 14 and 28 days correlating with the distinct increase of mineralization. No correlation was found throughout incubation with general microbial activity as determined by DMSO reduction. Analysis of the CaCl2 and ASE extracts by radio-TLC, radio-HPLC and GC/MS revealed that CfP was rapidly cleaved to free acid clodinafop (Cf), which was further (bio-) transformed; DT50 values (based on radio-TLC detection of the parent compound) were far below 1 day (CfP) and about 7 days (Cf). TLC analysis pointed to 2-(4-hydroxyphenoxy)-propionic acid as further metabolite. Due to fractionation of non-extractable residues, most of the 14C was associated with fulvic and humic acids, portions in humin fractions and non-humics were moderate and low, respectively. Using a special strategy, which included pre-incubation of the soil with CfP and then mineralization of 14C-CfP as criterion, a microorganism was isolated from the soil examined. The microorganism grew using CfP as sole carbon source with concomitant evolution of 14CO2. The bacterium was characterized by growth on commonly used carbon sources and by 16S rDNA sequence analysis. The sequence exhibited high similarity with that of Rhodococcus wratislaviensis (99.56%; DSM 44107, NCIMB 13082). 相似文献
995.
Abstract: Extinctions can leave species without mutualist partners and thus potentially reduce their fitness. In cases where non‐native species function as mutualists, mutualism disruption associated with species’ extinction may be mitigated. To assess the effectiveness of mutualist species with different origins, we conducted a meta‐analysis in which we compared the effectiveness of pollination and seed‐dispersal functions of native and non‐native vertebrates. We used data from 40 studies in which a total of 34 non‐native vertebrate mutualists in 20 geographic locations were examined. For each plant species, opportunistic non‐native vertebrate pollinators were generally less effective mutualists than native pollinators. When native mutualists had been extirpated, however, plant seed set and seedling performance appeared elevated in the presence of non‐native mutualists, although non‐native mutualists had a negative overall effect on seed germination. These results suggest native mutualists may not be easily replaced. In some systems researchers propose taxon substitution or the deliberate introduction of non‐native vertebrate mutualists to reestablish mutualist functions such as pollination and seed dispersal and to rescue native species from extinction. Our results also suggest that in places where all native mutualists are extinct, careful taxon substitution may benefit native plants at some life stages. 相似文献
996.
There is an international divide between net emissions importers and net emissions exporters, with industrialised nations mainly falling into the former and emerging economies the latter. Integrating emissions transfers into climate policy, so as not to disadvantage export-intensive countries, has been suggested to increase participation in international emissions reduction commitments. Consumption-based scenarios are presented for the UK identifying the geographic and sectorial source of emissions to meet future consumer demands given the current international climate policy landscape. The analysis is applied to the UK yet the discussion is applicable to international climate policy; assigning national responsibility for global emissions reductions; and extending the mitigation potential for net importing countries. Two trajectories for UK consumption emissions are calculated in which (1) international reduction targets are consistent with those pledged today equating to four degrees of temperature rise and (2) international reduction targets achieve a two degree future. By 2050 it is estimated that UK consumption emissions are 40–260% greater than UK territorial emissions depending on the strength of global reduction measures, and assuming the UK meets its 80% reduction in 1990 emissions by 2050 target. Cumulative emissions are presented alongside emissions trajectories, recognising that temperature rise is directly related to every tonne of carbon emitted. Whilst this paper argues that the current UK emissions targets underestimate the UK's contribution to global mitigation for two degrees, it shows how expanding the focus of policy towards consumption introduces new opportunities for reduction strategies at scale. The paper advocates the implementation of consumption-based emissions accounting which reveals underexploited policy interventions and increases the potential to break down barriers that exist between industrialised and emerging economies in international climate policy. 相似文献
997.
Rail transit is generally acknowledged as an alternative transport mode in contributing towards sustainable mobility. In addition to minimising negative externalities, rail transit has sustainable land-use opportunities to integrate transport- and spatial planning. The objective of this paper is to determine the impact of integrative light rail scenarios and their ability to curtail private vehicle driven urban sprawl in the Flemish rhombus.The paper proposes three light rail scenarios: an infrastructural scenario; tramification scenario; and spatial rail scenario, each covering a specific landscape structure to reorganise the dispersed spatial environment in Flanders in the long-term. We used the participatory multi-actor multi-criteria analysis (MAMCA) which incorporates the objectives of all involved stakeholders to assess the impact of the scenarios.The infrastructural alternative scenario gained most support among the involved stakeholders, on the grounds of improved multimodality, enhanced user amenities, reduced implementation costs, moderated greenhouse gas emissions and mitigated infrastructural barrier effects.Despite the merits of the infrastructural scenario in terms of stakeholder objectives, few possibilities are included to elaborate upon sustainable land-use development. In response to the low performance of this assessment criterion, catalyst measures are discussed to support the implementation. 相似文献
998.
根据昆明政府颁布的《昆明市松华坝水源保护区生产生活补助办法(试行)》要求,在系统探讨了松华坝水源保护区实施补助的重要性和必要性的基础上,分析了办法实行可能产生的效果,并针对性地提出实施建议。 相似文献
999.
Mapping, modeling, and valuing urban ecosystem services are important for integrating the ecosystem services concept in urban planning and decision-making. However, decision-support tools able to consider multiple ecosystem services in the urban setting using complex and heterogeneous data are still in early development. Here, we use New York City (NYC) as a case study to evaluate and analyze how the value of multiple ecosystem services of urban green infrastructure shifts with shifting governance priorities. We first examined the spatial distribution of five ecosystem services – storm water absorption, carbon storage, air pollution removal, local climate regulation, and recreation – to create the first multiple ecosystem services evaluation of all green infrastructure in NYC. Then, combining an urban ecosystem services landscape approach with spatial multicriteria analysis weighting scenarios, we examine the distribution of these ecosystem services in the city. We contrast the current NYC policy preference – which is focused on heavy investment in stormwater absorption – with a valuation approach that also accounts for other ecosystem services. We find substantial differences in the spatial distribution of priority areas for green infrastructure for the valuation scenarios. Among the scenarios we examined for NYC, we find that a scenario in which only stormwater absorption is prioritized leads to the most unevenly distributed ES values. By contrast, we find least variation in ES values where stormwater absorption, local climate regulation, carbon storage, air pollution removal, and recreational potential are all weighted equally.We suggest that green infrastructure planning strategies should include all landscape components that contribute to the production of ecosystem services and consider how planning priority alternatives generate different ecosystem services values. 相似文献
1000.
针对各地公路碳排放的空间差异与关联特征,制定合理的低碳策略,实现各地协同碳减排,是行业可持续发展的热点问题。以江西省为研究对象,采用空间自相关、社会网络分析和引力模型等分析11地市公路行业碳排放的空间差异与关联,识别社会网络的结构特征及其演变趋势,明确不同地市在网络中的地位和作用,结果显示:(1)公路货运是公路行业碳排放的最主要来源;(2)江西省公路行业碳排放整体上呈现空间随机分布,不存在全局的空间聚集性,且局部空间聚集特征不断变化;(3)公路行业碳排放网络逐渐从南昌、新余双中心结构演变为南昌为主的单中心结构,网络的协同作用整体呈减弱趋势,核心地市对外围地市的影响力和带动作用不足。 相似文献