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101.
Chemical and colloidal analyses of natural seep water collected from the exploratory studies facility inside Yucca Mountain,Nevada, USA 总被引:1,自引:0,他引:1
Cizdziel JV Guo C Steinberg SM Yu Z Johannesson KH 《Environmental geochemistry and health》2008,30(1):31-44
Yucca Mountain is being considered as a geological repository for the USA’s spent nuclear fuel and high-level nuclear waste.
Numerous groundwater seeps appeared during March 2005 within the exploratory studies facility (ESF), a tunnel excavated in
the mountain. Because of the relevance to radionuclide transport and unsaturated zone-modeling studies, we analyzed the seep
samples for major anions and cations, rare earth elements, and colloids. Major ion species and elemental concentrations in
seep samples reflect interaction of the water with the volcanic rock and secondary calcites. Elemental fractograms from flow-injection
field-flow fractionation ICP–MS scans detected Br, Ca, Cl, Cu, Fe, I, Mg, Si, Sr, W, and U at void fractions, suggesting they
may be present in the form of dissolved anions. Colloids approximately 10 nm in hydrodynamic diameter, possibly calcite, were
also present in the seepage samples. Geochemical calculations indicate, however, these may be an artifact (not present in
the groundwater) which arose because of loss of CO2 during sample collection and storage. 相似文献
102.
The systematic conservation planning literature invariably assumes that the biodiversity features being preserved in sites do not change through time. We develop a conservation planning framework for ecosystems where disturbance events and succession drive vegetation dynamics. The framework incorporates three key attributes of disturbance theory: heterogeneity in disturbance rates, spatial correlation between disturbance events and different impacts of disturbance. In our conservation problem we wish to maximise the chance that we represent a certain number of successional types given a cap on the number of sites we can conserve. Correlation between disturbance events dramatically complicates the problem of choosing the optimal suite of sites. However, in our problem we discover that spatial correlation in disturbances affects the optimal reserve network very little. The reason is twofold: (i) through our probabilistic framework we focus on the long-term effectiveness of reserve networks and (ii) in the dynamics considered in our model the state of a site is not only affected by the most recent (correlated) disturbance event but also by the site's long-term stochastic history which blurs the impact of spatial correlation. If successional states are the conservation target rather than individual species then, conserving a site can only contribute to meeting one target. However, given that correlation of disturbance events may be ignored, we show that if the number of candidate reserves is sufficiently large the statistical dependence of different conservation targets may be ignored, too. We conclude that the computational complexity of reserve selection methods for dynamic ecosystems can be much simpler than they first appear. 相似文献
103.
东洞庭湖保护区1989~1998年水禽栖息地动态研究 总被引:7,自引:0,他引:7
栖息地的改变是全球生物多样性存在的最大威胁。利用卫星遥感技术和地理信息系统的空间分析功能,从景观尺度上研究了东洞庭湖自然保护区1989~1998年越冬水禽栖息地的动态变化特征,结果表明:1989~1998年水体、泥滩地、草滩地和水田等水禽适宜栖息地的面积在减小,破碎化程度有所增加,而芦苇滩地、旱地、林地、建成区这几类水禽分布较少栖息地类型的面积和破碎化程度的变化正好相反;近10年来水禽栖息地的变化比较明显,其中草滩地演变为芦苇滩地及水田改为旱作农田的变化最为突出,变化的面积分别占整个保护区面积的10.66%和6.13%。这些变化趋势意味着研究区近10年来水禽的适宜栖息地在退化。针对变化的原因,论文还对该区域生物多样性的保护与栖息地管理提出了可行的建议。 相似文献
104.
将华莺山建设成为川东生态屏障 总被引:2,自引:0,他引:2
生态环境保护是环保工作的重要内容,是实地西部大开发的主要工程之一。本文就控制环境污染、保护生物多样性、提高植被覆盖率论述了环境保护与生态环境建设的关系,并依据华蓥山系存在的生态环境问题,阐明了加强环境保护与川东生态屏障建设的基本对策。 相似文献
105.
通过对完达山地区进行长期调查发展,该地区共有药用植物资源80科224种,并以植物分类学进行了统计,提出了合理开发利用药用植物的建议,为研究和合理利用完达山地区药用植物资源提供了基础材料。 相似文献
106.
山东崂山生物多样性及保护对策 总被引:1,自引:0,他引:1
根据多年来对青岛崂山生物资源的调查和文献资料,研究了崂山生物多样性的特点,分析了其在山东生物多样性保护中的地位,提出了崂山生物多样性保护对策和建议.研究表明:崂山生物多样性具有物种丰富度高、密度大,特有种、重点保护物种多,植物成分复杂,生态系统类型多样,古树名木众多,遗传多样性丰富的特点,崂山是山东乃至全国生物多样性保护的“关键区“之一. 相似文献
107.
Nature Articulations in Norwegian Advertising Discourse: A Depoliticized Discourse of Climate Change
This article deals with how nature is articulated in public discourse and more specifically how humans’ relationship to nature is constructed via such articulations. Based on critical cultural analyses of ads presented in a Norwegian context, the article claims articulations of nature serve to a depoliticization of nature, which silence social differences and reduce environmental politics to individual moral action. Several rhetorical patterns of particular relevance to the articulation of nature are discussed, pointing out how disparate, sometimes conflicting, understandings of nature are rhetorically configured and aligned in ways that benefit a global market economy. There is a discursive distancing of nature and everyday life, even as nature remains valorized and very much central to national identity. This constrains citizens’ political engagement and undermines understandings of how to govern nature. 相似文献
108.
Both the ‘cascade model’ of ecosystem service provision and the Driver-Pressure-State-Impact-Response framework individually contribute to the understanding of human–nature interactions in social–ecological systems (SES). Yet, as several points of criticism show, they are limited analytical tools when it comes to reproducing complex cause–effect relationships in such systems. However, in this paper, we point out that by merging the two models, they can mutually enhance their comprehensiveness and overcome their individual conceptual deficits. Therefore we closed a cycle of ecosystem service provision and societal feedback by rethinking and reassembling the core elements of both models. That way, we established a causal sequence apt to describe the causes of change to SES, their effects and their consequences. Finally, to illustrate its functioning we exemplified and discussed our approach based on a case study conducted in the Alpujarra de la Sierra in southern Spain.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0651-y) contains supplementary material, which is available to authorized users. 相似文献109.
Anna Maria J?nsson Olle Anderbrant Jennie Holmér Jacob Johansson Guy Schurgers Glenn P. Svensson Henrik G. Smith 《Ambio》2015,44(3):249-255
In recent years, climate impact assessments of relevance to the agricultural and forestry sectors have received considerable attention. Current ecosystem models commonly capture the effect of a warmer climate on biomass production, but they rarely sufficiently capture potential losses caused by pests, pathogens and extreme weather events. In addition, alternative management regimes may not be integrated in the models. A way to improve the quality of climate impact assessments is to increase the science–stakeholder collaboration, and in a two-way dialog link empirical experience and impact modelling with policy and strategies for sustainable management. In this paper we give a brief overview of different ecosystem modelling methods, discuss how to include ecological and management aspects, and highlight the importance of science–stakeholder communication. By this, we hope to stimulate a discussion among the science–stakeholder communities on how to quantify the potential for climate change adaptation by improving the realism in the models. 相似文献
110.
Evolutionary psychology has been proposed as an analytic framework for the behavioral effects of landscapes displayed in advertising. In this study, an evolutionary and environmental psychology approach is used to analyze affective reactions to advertising depicting specific natural environments or urban scenes, both prominent ingredients of contemporary advertising imagery. The experimental field study exposed 750 participants at random to one advert of a set of 13 experimental green energy advertisements, each displaying a different biome. Six basic emotional responses (pleasure, arousal, happiness, freedom, safety, and interest) as well as attitude toward the ad and brand attitude were assessed subsequently. Anova and structural equation analysis were used for data analysis. Results of the study confirm the leading opinion on generalized more positive behavioral effects toward visual stimuli representing nature scenes with biospheric contents as opposed to pictures of urban environments or desert settings. In line with earlier empirical research, further findings do not support the hypothesis on an innate preference for savanna landscapes in adults but confirm preferences for images of lush green landscapes with water and familiar biomes. Overall results give significant support to the application of environmental and evolutionary psychology to advertising. 相似文献