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211.
Box cores and surficial sediments collected from the shelf, slope and Okinawa Trough of the East China Sea were analyzed for loss on ignition, and concentration and speciation of Al, Fe, Mn, Pb, Cd, Cu and Zn. in general, concentrations of these metals are higher in the inner shelf and lower in the midshelf, but the highest LOI, Cd and Mn levels are found in the Okinawa Trough. Spatial distributions of these metals in surficial sediments indicate that the Yangtze River is the major source for materials deposited in the inner shelf. the results of a six-stage sequential leaching experiment indicate that the fluvial input includes natural (e.g., Al and Fe) and anthropogenic (e.g., Pb) materials. the depletion concentration of these metals in the midshelf sediments reflects the dominance (~ 70%) of coarse, relict sand, while the enrichments in the inner shelf and the Okinawa Trough sediments are due to the fine grained, organic-rich sediments. the speciation of Mn in the sediments of the Okinawa Trough indicates that its distribution is diagentically or hydrothermally controlled. 相似文献
212.
Pot and hydroponic trials as well as tests on samples collected in a mining area and in two different urban sites of Tuscany were carried out on Arum italicum Mill (Italian arum) plants. Zinc and cadmium contents were determined by differential pulse anodic stripping voltammetry (DPASV) in different organs of about 180 samples. After 65 days treatment, zinc and cadmium median contents in leaves of plants grown hydroponically in solutions containing both metals at different concentrations fell within the range of 281-2022 and 8.3-45.1 μg g-1 (dry weight), respectively. Some Italian arum plants were also cultivated in pots in the presence or absence of malate or citrate in order to evaluate the role of these ligands in zinc and cadmium accumulation. Citrate enhanced cadmium uptake compared to malate. 相似文献
213.
Joanna Becker 《国际发展与全球生态学杂志》2013,20(1):23-32
SUMMARY This paper describes the evolution of an evaluation method developed initially to assess progress towards sustainable development for various land use activities in Costa Rica. Since that time, the method has been expanded to apply to all types of business activities in any location, and refined so that a numerical score can be provided for each attribute. These scores can then be presented graphically in four categories. The method has since been tested on a variety of businesses and is being refined for electronic submission and display of the results. The benefits of this approach, as well as its shortcomings and some of the problems resolved, are presented. 相似文献
214.
Sarah E. Fredericks 《国际发展与全球生态学杂志》2013,20(6):490-499
At least since the Brundtland Report, technical assessments of what can be sustained and values about what is desirable to sustain, for whom, and for how long have been intertwined. This intersection is particularly evident in the assumption that justice among people living today and between present and future generations is a key part of sustainability. In official international policy documents and academic studies of sustainability, this justice may include the equitable distribution of environmental benefits and burdens, distributive justice, or the ability of people to meaningfully contribute to decisions that affect their lives, participatory justice. Yet, the process of developing indicators and indexes to track movement toward or away from sustainability has been dominated by technical, economic, and environmental assessments. This raises questions about whether or not indexes align with and thus will monitor and encourage progress toward sustainability in a technically possible and desirable way. To begin to answer this question, this paper identifies definitions of justice used in sustainability discourse and evaluates the degree to which sustainability indicators and indexes align with these concepts. The 2010 Environmental Performance Index, Eurostat's Sustainable Development Indicators, and a group of local indicators and indexes are examined. It is found that the indicators embody various aspects of justice, though they are still significantly limited by the available data, especially as they generally cannot monitor inequities between subpopulations and have a limited capacity to monitor progress toward participatory justice. 相似文献
215.
Anne M. Winther 《国际发展与全球生态学杂志》2013,20(4):338-351
ABSTRACTAlthough sustainable development was defined in the Brundtland Report almost 30 years ago, the current usage of the concepts of sustainability and sustainable development remain highly equivocal. In the context of rural communities, multiple interpretations and weak definitions lead to confusion in understanding what comprises a sustainable rural community. Building on existing definitions (e.g. Baker’s, 2006, ‘Ladder of Sustainable Development’), models (principally, The Egan Review’s, 2004, ‘Components of Sustainable Communities’) and findings of this study, a sustainable community is defined and a holistic model of a sustainable place-based rural community is presented. This model, the sustainable community design (SCD) is used as the basis for analysing community sustainability, which is measured using mixed methods and scorecard assessment. Sensitivity of the method is demonstrated with inter- and intra-community variations in sustainability across three diverse Scottish rural communities. Intra-community variations illustrate heterogeneity in community sustainability, explain ambiguity in characterisations of an individual community’s sustainability, and highlight the importance of an interdisciplinary and holistic approach to community development. The SCD framework is presented as a useful tool for meso-level sustainability assessment and to facilitate the sustainable development of rural communities. 相似文献
216.
将定量指标与定性指标融为一体,从城市经济、文化教育、基础设施、生态环境和社会保障5个方面,构建生态宜居城市指标体系,并整合层次分析法(AHP)和风玫瑰图法,进行生态宜居化程度综合评价与分析。以天津市为例进行研究,结果显示本文所建立的指标体系能够客观地反映城市的生态宜居建设情况,并能根据评价结果分析出城市的发展潜力与存在... 相似文献
217.
矿井通风系统优化方案的评价涉及到许多模糊的、不确定因素.从安全、技术、经济角度出发,选取15个技术指标,建立了评价指标体系.将层次分析法(AHP)与模糊模式识别(FPR)理论相结合,采用层次分析法确定指标权重,多级模糊模式识别法构造最优相对隶属度矩阵以判断样本级别,在此基础上建立了AHP-FPR评价模型.通过对平煤八矿通风系统优化改造方案的评价实例证明,该模型实用性较强,可为管理者提供决策依据. 相似文献
218.
Males often use elaborate courtship displays to attract females for mating. Much attention, in this regard, has been focused
on trying to understand the causes and consequences of signal variation among males. Far less, by contrast, is known about
within-individual variation in signal expression and, in particular, the extent to which males may be able to strategically
adjust their signalling output to try to maximise their reproductive returns. Here, we experimentally investigated male courtship
effort in a fish, the Australian desert goby, Chlamydogobius eremius. When offered a simultaneous choice between a large and a small female, male gobies spent significantly more time associating
with, and courting, the former, probably because larger females are also more fecund. Male signalling patterns were also investigated
under a sequential choice scenario, with females presented one at a time. When first offered a female, male courtship was
not affected by female size. However, males adjusted their courtship effort towards a second female depending on the size
of the female encountered previously. In particular, males that were first offered a large female significantly reduced their
courtship effort when presented with a subsequent, smaller, female. Our findings suggest that males may be able to respond
adaptively to differences in female quality, and strategically adjust their signalling effort accordingly. 相似文献
219.
A Realistic Assessment of the Indicator Potential of Butterflies and Other Charismatic Taxonomic Groups 总被引:1,自引:0,他引:1
Abstract: Charismatic groups of animals and plants often are proposed as sentinels of environmental status and trends. Nevertheless, many claims that a certain taxonomic group can provide more-general information on environmental quality are not evaluated critically. To address several of the many definitions of indicator species, we used butterflies to explore in some detail the attributes that affect implementation of indicators generically. There probably are few individual species, or sets of species, that can serve as scientifically valid, cost-effective measures of the status or trend of an environmental phenomenon that is difficult to measure directly. Nevertheless, there are species with distributions, abundances, or demographic characteristics that are responsive to known environmental changes. In this context, single or multiple species can serve as indicators when targets are defined explicitly, ecological relationships between the target and the putative indicators are well understood, and data are sufficient to differentiate between deterministic and stochastic responses. Although these situations exist, they are less common than might be apparent from an extensive and often confounded literature on indicators. Instead, the public appeal of charismatic groups may be driving much of their acclaim as indicators. The same taxon may not be appropriate for marketing a general conservation mission and for drawing strong inference about specific environmental changes. To provide insights into the progress of conservation efforts, it is essential to identify scientific and practical criteria for selection and application of indicators and then to examine whether a given taxonomic group meets those criteria . 相似文献
220.
The present study aims to determine the phytotoxic effects of lead (Pb) on corn (Zea mays), wheat (Triticum aestivum), cucumber (Cucumis sativus), cabbage (Brassica oleracea) and lettuce (Lactuca sativa) and to identify the sensitive crop species and appropriate bioassays for potential use in phytotoxicity assessment of Pb-contaminated soil. In a laboratory experiment, Pb(NO3)2 was added to the background soil to obtain eight Pb treatments. The results indicate that the seed germination rate of lettuce decreases by 14.44%, 30.00% and 40.00% at 2000, 3000 and 4000 mg Pb kg?1 soil, respectively. However, the germination of corn, wheat, cucumber and cabbage is not significantly influenced by the Pb-contaminated soil treated with all the tested concentrations. Furthermore, the root elongation is more sensitive to Pb than is seed germination. The minimum concentrations of adverse effect of maize, wheat, cucumber, cabbage and lettuce are 2000, 3000, 1300, 800 and 300 mg Pb kg?1 soil, respectively. Moreover, dicotyledon species are more sensitive than monocotyledon species. In the genotoxicity study, the mitotic index (MI) fluctuates with an increasing Pb concentration. The micronuclei (MN) frequencies of cucumber, cabbage and lettuce exhibit a dose-dependent effect at concentrations ranging from 1300 to 4000 mg Pb kg?1 soil. It can be concluded that lettuce is a good candidate for indicating the toxicity of Pb in soil. Root elongation and the micronucleus frequency of dicotyledon are appropriate bioassays for potential use in phytotoxicity assessment of Pb-contaminated soil. 相似文献