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991.
The halophytic shrub Halimione portulacoides is known to be capable of growth in soils containing extremely high concentrations of Zn. This study evaluated in detail the tolerance and accumulation potential of H. portulacoides under moderate and high external Zn levels. A greenhouse experiment was conducted in order to investigate the effects of a range of Zn concentrations (0-130 mmol L−1) on growth and photosynthetic performance by measuring relative growth rate, total leaf area, specific leaf area, gas exchange, chlorophyll fluorescence parameters and photosynthetic pigment concentrations. We also determined the total zinc, nitrogen, phosphorus, calcium, magnesium, sodium, potassium, iron and copper concentrations in the plant tissues. H. portulacoides demonstrated hypertolerance to Zn stress, since it survived with leaf concentrations of up to 2300 mg Zn kg−1 dry mass, when treated with 130 mmol Zn L−1. Zinc concentrations greater than 70 mmol L−1 in the nutrient solution negatively affected plant growth, in all probability due to the recorded decline in net photosynthesis rate. Our results indicate that the Zn-induced decline in the photosynthetic function of H. portulacoides may be attributed to the adverse effect of the high concentration of the metal on photosynthetic electron transport. Growth parameters were virtually unaffected by leaf tissue concentrations as high as 1500 mg Zn kg−1 dry mass, demonstrating the strong capability of H. portulacoides to protect itself against toxic Zn concentrations. The results of our study indicate that this salt-marsh shrub may represent a valuable tool in the restoration of Zn-polluted areas. 相似文献
992.
Federal land managers are faced with the task of balancing multiple uses and goals when making decisions about land use and
the activities that occur on public lands. Though climate change is now well recognized by federal agencies and their local
land and resource managers, it is not yet clear how issues related to climate change will be incorporated into on-the-ground
decision making within the framework of multiple use objectives. We conducted a case study of a federal land management agency
field office, the San Juan Public Lands Center in Durango, CO, U.S.A., to understand from their perspective how decisions
are currently made, and how climate change and carbon management are being factored into decision making. We evaluated three
major management sectors in which climate change or carbon management may intersect other use goals: forests, biofuels, and
grazing. While land managers are aware of climate change and eager to understand more about how it might affect land resources,
the incorporation of climate change considerations into everyday decision making is currently quite limited. Climate change
is therefore on the radar screen, but remains a lower priority than other issues. To assist the office in making decisions
that are based on sound scientific information, further research is needed into how management activities influence carbon
storage and resilience of the landscape under climate change. 相似文献
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994.
Evaluating Infiltration Requirements for New Development Using Extreme Storm Transposition: A Case Study from Dane County,WI 下载免费PDF全文
Nicholas G. Hayden Kenneth W. Potter David S. Liebl 《Journal of the American Water Resources Association》2016,52(5):1170-1178
Changes in land use and extreme rainfall trends can lead to increased flood vulnerability in many parts of the world, especially for urbanized watersheds. This study investigates the performance of existing stormwater management strategies for the Upper Yahara watershed in Dane County, WI to determine whether they are adequate to protect urban and suburban development from an extreme rainfall. Using extreme storm transposition, we model the performance of the stormwater infiltration practices required for new development under current county ordinances. We find during extreme rainfall the volume of post‐development runoff from impervious surfaces from a typical site would increase by over 55% over pre‐development conditions. We recommend the ordinance be strengthened to reduce vulnerability to flooding from future urban expansion and the likely increase in the magnitude and frequency of extreme storms. 相似文献
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S. Alvandi W. Li M. Schönemann C. Herrmann 《International Journal of Sustainable Engineering》2016,9(6):354-362
Value stream mapping (VSM) is a well-accepted tool within lean manufacturing concept which is often used for analysing and designing the flow of materials and information required to manufacture a product. However, the analysis is static and single product oriented, which fails to cope with either the variation of production plan or a multi-product environment. In addition, the environmental impact of a manufacturing system is highly associated with the dynamic consumption of energy and resources. Despite the recent integration of VSM with simulation or environmental studies (in the domain of energy efficiency), still neglected is the dynamic assessment of all the resources involved in a multi-product production environment. This paper presents a methodology for modelling multi-product manufacturing systems with dynamic material, energy and information flows with the aim to generate economic and environmental value stream maps (E2VSM). The proposed methodology is validated with an industrial case. 相似文献
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In the midst of rapidly proliferating engagement efforts around climate adaptation, attention to the design and evaluation of decision support processes and products is warranted. We report on the development and evaluation of a process framework called the Vulnerability, Consequences, and Adaptation Planning Scenarios (VCAPS) process. VCAPS is a systematic approach to integrate local knowledge with scientific understanding by providing opportunities for facilitated, deliberative learning-based activities with local decision makers about climate change vulnerability and adaptation. We introduce the conceptual basis of the process in analytic-deliberation, hazard management, and vulnerability. Our evaluations from eight coastal communities where the approach was applied point to four assets of VCAPS: it promotes synthesis of local and scientific knowledge; it stimulates systems thinking and learning; it facilitates governance by producing action plans with transparent justifications; and it accommodates participant time constraints and preferences. 相似文献
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