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471.
环境影响评价制度和社会稳定风险评估制度作为预防和控制环境影响、创新社会风险管理的重要制度,实施以来发挥了重要作用,但也出现了工作边界和内容范围交叉的问题。尤其是近年来,环境污染焦虑引发社会风险事件的建设项目不断增多,导致两者的"天然联系"愈发紧密,工作存在模糊地带的问题愈发凸显,致使建设项目行政审批繁复、执行力差。在梳理环评、稳评的发展历程和存在问题的基础上,深入分析了环评和稳评的法律地位、适用范围、评价目标、评价内容、实施主体和程序上的异同,剖析了两者在制度设计和内容衔接方面的关系,并从理清工作边界职责、环境社会风险评估结果共享、强化稳评公众参与等方面提出了环评和稳评政策衔接的建议,为政府有效实施建设项目环境、社会监管提供决策参考。 相似文献
472.
工伤事故灾害空间分布特征及其与经济增长的关联性 总被引:1,自引:0,他引:1
以经济区域为基本单元,在对工伤事故灾害和经济增长空间分布特征描述的基础上,采用面板回归工具分析两者的空间关联性。研究结果证明:工伤事故灾害与经济增长规模之间存在梯度空间差异规律,经济增长对工伤事故灾害有重要影响,并且不同经济增长对工伤事故灾害的影响存在较大差异性,工业化、经济一体化程度和人力资本素质的区域不均衡是造成工伤事故灾害空间分布差异的重要变量。 相似文献
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Goal, Scope and Background Marine cage aquaculture produces a large amount of waste that is released directly into the environment. To effectively manage
the mariculture environment, it is important to determine the carrying capacity of an aquaculture area. In many Asian countries
trash fish is dominantly used in marine cage aquaculture, which contains more water than pellet feed. The traditional nutrient
loading analysis is for pellet feed not for trash fish feed. So, a more critical analysis is necessary in trash fish feed
culturing areas.
Methods Corresponding to FCR (feed conversion rate), dry feed conversion rate (DFCR) was used to analyze the nutrient loadings from
marine cage aquaculture where trash fish is used. Based on the hydrodynamic model and the mass transport model in Xiangshan
Harbor, the relationship between the water quality and the waste discharged from cage aquaculture has been determined. The
environmental carrying capacity of the aquaculture sea area was calculated by applying the models noted above.
Results Nitrogen and phosphorus are the water quality parameters considered in this study. The simulated results show that the maximum
nitrogen and phosphorus concentrations were 0.216 mg/L and 0.039 mg/L, respectively. In most of the sea area, the nutrient
concentrations were higher than the water quality standard. The calculated environmental carrying capacity of nitrogen and
phosphorus in Xiangshan Harbor were 1,107.37 t/yr and 134.35 t/yr, respectively. The waste generated from cage culturing in
2000 has already exceeded the environmental carrying capacity.
Discussion Unconsumed feed has been identified as the most important origin of all pollutants in cage culturing systems. It suggests
the importance of increasing the feed utilization and improving the feed composition on the basis of nutrient requirement.
For the sustainable development of the aquaculture industry, it is an effective management measure to keep the stocking density
and pollution loadings below the environmental carrying capacity.
Conclusions The DFCR-based nutrient loadings analysis indicates, in trash fish feed culturing areas, that it is more critical and has
been proved to be a valuable loading calculation method. The modeling approach for Xiangshan Harbor presented in this paper
is a cost-effective method for assessing the environmental impact and determining the capacity. Carrying capacity information
can give scientific suggestions for the sustainable management of aquaculture environments.
Recommendations and Perspectives It has been proved that numerical models were convenient tools to predict the environmental carrying capacity. The development
of models coupled with dynamic and aquaculture ecology is a requirement of further research. Such models can also be useful
in monitoring the ecological impacts caused by mariculture activities.
ESS-Submission Editor: Hailong Wang (hailong.wang@ensisjv.com) 相似文献
475.
Future habitat loss and extinctions driven by land‐use change in biodiversity hotspots under four scenarios of climate‐change mitigation
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Brian Barker Thomas M. Brooks Louise P. Chini Qiongyu Huang Rachel M. Moore Jacob Noel George C. Hurtt 《Conservation biology》2015,29(4):1122-1131
Numerous species have been pushed into extinction as an increasing portion of Earth's land surface has been appropriated for human enterprise. In the future, global biodiversity will be affected by both climate change and land‐use change, the latter of which is currently the primary driver of species extinctions. How societies address climate change will critically affect biodiversity because climate‐change mitigation policies will reduce direct climate‐change impacts; however, these policies will influence land‐use decisions, which could have negative impacts on habitat for a substantial number of species. We assessed the potential impact future climate policy could have on the loss of habitable area in biodiversity hotspots due to associated land‐use changes. We estimated past extinctions from historical land‐use changes (1500–2005) based on the global gridded land‐use data used for the Intergovernmental Panel on Climate Change Fifth Assessment Report and habitat extent and species data for each hotspot. We then estimated potential extinctions due to future land‐use changes under alternative climate‐change scenarios (2005–2100). Future land‐use changes are projected to reduce natural vegetative cover by 26‐58% in the hotspots. As a consequence, the number of additional species extinctions, relative to those already incurred between 1500 and 2005, due to land‐use change by 2100 across all hotspots ranged from about 220 to 21000 (0.2% to 16%), depending on the climate‐change mitigation scenario and biological factors such as the slope of the species–area relationship and the contribution of wood harvest to extinctions. These estimates of potential future extinctions were driven by land‐use change only and likely would have been higher if the direct effects of climate change had been considered. Future extinctions could potentially be reduced by incorporating habitat preservation into scenario development to reduce projected future land‐use changes in hotspots or by lessening the impact of future land‐use activities on biodiversity within hotspots. 相似文献
476.
陕西省城市化与生态环境系统耦合关系 总被引:1,自引:0,他引:1
采用层次分析法(AHP)和系统科学的理论构建了城市化与生态环境系统的评价指标体系和耦合模型,并将这个耦合系统的演化周期分为低级共生、协调发展等4个阶段,根据耦合度为45°时,耦合效果最佳的理论又可将协调发展阶段分为相对协调、最佳协调、低度协调3个状态.1990-2008年陕西省的城市化综合指数呈现直线上升的趋势,生态环... 相似文献
477.
保护生态系统、提高居民福祉是实现联合国2030可持续发展目标的核心内容。在分析秦巴山区生态系统服务与居民福祉时空演化特征的基础上,采用弹性系数揭示了二者的时空耦合关系。研究发现:(1)1990—2018年秦巴山区水源涵养总量、土壤保持总量均呈波动下降趋势,碳储量总量则呈缓慢增长趋势,且各生态系统服务呈不同的空间分异特征。(2)1990—2018年居民福祉呈上升趋势,增幅高达220%,并呈“南高北低”的分布格局。(3)县域尺度上,三种生态系统服务与居民福祉明显不协调发展。其中,水源涵养、固碳服务与居民福祉的耦合关系均以“福祉增—服务减”为主,占比分别为88.75%、62.5%;而土壤保持服务与居民福祉的耦合关系则以“双增”为主,占比为57.5%。此外,各项生态系统服务与居民福祉反向变化区多分布于汉江河谷盆地和秦岭山脉中段。研究结果可为促进贫困山区生态系统服务与居民福祉协调发展提供决策依据。 相似文献
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479.
Although transformational leadership has been investigated in connection with change at higher levels of organizations, less is known about its “in‐the‐trenches” impact. We examined relations among transformational leadership, explicit change reactions (i.e., relationship quality), change frequency, and change consequences (i.e., task performance and organizational citizenship behavior (OCB)) during continuous incremental organizational change at lower hierarchical levels. In a sample of 251 employees and their 78 managers, analyses revealed that the quality of relationships between leaders and employees mediated the influence of transformational leadership on employee task performance and OCB. We also found that change frequency moderated the positive association of relationship quality with task performance and OCB, such that associations were stronger when change frequency was high. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
480.