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111.
112.
The tropical rainforest of Malaysia holds one of the richest flora in the world. The favourable climate has produced flora of amazing richness and variety. Terrestrial vegetation of tropical rainforests is an important feature of the environment. Plants play a major role in the environment and conservation of a particular environment depends fundamentally on the maintenance of existing plants and their communities and hierarchies. Interference in the balance of the ecosystem may produce radical changes that lead to progressive deviations from the original situation. Therefore, the application of a computer technology in the form of an expert system (ES) will be able to help in the analysis and management of the EIA information. The ES is named VEGEVIC. Application of the system will lead to greater consistency in the application of EIA through implementation of a standard approach.  相似文献   
113.
Pteris vittata is known to hyperaccumulate As but the mechanism is poorly understood. We found an increase of As concentration with increasing soil solution As concentrations, but P application had no impact, although plant P concentrations responded to different rates of P supply. As in fronds was dominantly (82–89%) present in the form of AsIII. In roots we detected 45% as AsIII which is higher than reported in previous studies and supports substantial As-reduction to take place in roots. We detected PC2/3GS–AsIII, PC2–GS–AsIII and (PC2)2–AsIII in increasing amounts with application of As. The total amount of PC was in the range reported previously and far too small to assign a significant role in As detoxification to PCs. The close correlation between S and As in fronds and the lack of data on sulphur uptake and metabolism indicates the need for a detailed investigation on sulphur nutritional status and As metabolism in P. vittata.  相似文献   
114.
This paper is a response to a recent special issue of Regional Environmental Change, “Quantifying vulnerability to drought from different disciplinary perspectives” (vol. 8, number 4, 2008). In this paper, we examine some of the challenges facing efforts to understand vulnerability to drought through quantification as they are manifest in some of the articles in this special issue.
Edward R. CarrEmail:
  相似文献   
115.
We present highly time-resolved measurements of organic molecular markers in downtown Pittsburgh, which are used to investigate sources contributing to atmospheric aerosols in the area. Two-hour average concentrations of condensed-phase and semivolatile organic species were measured using a Thermal Desorption Aerosol GC/MS (TAG). Concentrations for mobile source markers like hopanes had regular diurnal and day-of-week patterns. Pairing high time-resolved measurements with meteorological data helped identify contributions from known point sources for markers correlated with wind direction. Black carbon (BC), volatile organic compounds (VOCs) and organic molecular markers were apportioned to sources using the Chemical Mass Balance (CMB) and Positive Matrix Factorization (PMF) receptor models. Diesel and gasoline mobile source factors were identified as the main sources of BC in the downtown Pittsburgh area, contributing 67% and 20% of the study-average BC. 13% of the BC was associated with a source factor tentatively identified as an industrial or regional source. The high time resolution of the TAG has the potential to provide important new insight into source apportionment efforts using organic molecular marker measurements.  相似文献   
116.
Warning systems with the ability to predict floods several days in advance have the potential to benefit tens of millions of people. Accordingly, large‐scale streamflow prediction systems such as the Advanced Hydrologic Prediction Service or the Global Flood Awareness System are limited to coarse resolutions. This article presents a method for routing global runoff ensemble forecasts and global historical runoff generated by the European Centre for Medium‐Range Weather Forecasts model using the Routing Application for Parallel computatIon of Discharge to produce high spatial resolution 15‐day stream forecasts, approximate recurrence intervals, and warning points at locations where streamflow is predicted to exceed the recurrence interval thresholds. The processing method involves distributing the computations using computer clusters to facilitate processing of large watersheds with high‐density stream networks. In addition, the Streamflow Prediction Tool web application was developed for visualizing analyzed results at both the regional level and at the reach level of high‐density stream networks. The application formed part of the base hydrologic forecasting service available to the National Flood Interoperability Experiment and can potentially transform the nation's forecast ability by incorporating ensemble predictions at the nearly 2.7 million reaches of the National Hydrography Plus Version 2 Dataset into the national forecasting system.  相似文献   
117.
The Amazon Delta and Estuary (ADE) is a region of continental and global ecological importance. Controversy, many of the basic infrastructure and services essential for quality of life and sustainable development of this delta are absent. Using a conceptual model to define socio-economic vulnerability in the urban ADE, a thorough assessment of indicators including sanitation services, housing conditions, household income, population, flood risk and unplanned settlements was conducted in 41 cities at the census sector scale (n = 2938). A multi criterion index was applied to classify urban vulnerability from three dimensions: flood exposure, socio-economic sensitivity and infrastructure. This is the first study to examine urban vulnerability within and between urban areas of the ADE. Results indicated that most of the urban sectors of the ADE are exposed to potential risks due to a combination of flood hazards, poverty and basic structural deficiencies such as insufficient drinking water or inadequate waste water collection, with several sectors being afflicted by similar problems. The assessment of vulnerability indicates that 60–90 % of the urban population live in conditions of moderate to high degree of vulnerability. The ADE cities presented a pattern where vulnerability increases from city center to their newly developed urban areas. Inadequate planning coupled with rapid urbanization has contributed to the development of unplanned settlements in almost half of the urban sectors of the ADE. Combined, these factors contribute to widespread socio-economic vulnerability along the urban spaces of the ADE, increasing exposure to health risks and more frequent seasonal and stochastic events such as storm surges and high flooding levels.  相似文献   
118.
There is global interest in recovering locally extirpated carnivore species. Successful efforts to recover Louisiana black bear in Louisiana have prompted interest in recovery throughout the species’ historical range. We evaluated support for three potential black bear recovery strategies prior to public release of a black bear conservation and management plan for eastern Texas, United States. Data were collected from 1,006 residents living in proximity to potential recovery locations, particularly Big Thicket National Preserve. In addition to traditional logistic regression analysis, we used conditional probability analysis to statistically and visually evaluate probabilities of public support for potential black bear recovery strategies based on socioeconomic characteristics. Allowing black bears to repopulate the region on their own (i.e., without active reintroduction) was the recovery strategy with the greatest probability of acceptance. Recovery strategy acceptance was influenced by many socioeconomic factors. Older and long-time local residents were most likely to want to exclude black bears from the area. Concern about the problems that black bears may cause was the only variable significantly related to support or non-support across all strategies. Lack of personal knowledge about black bears was the most frequent reason for uncertainty about preferred strategy. In order to reduce local uncertainty about possible recovery strategies, we suggest that wildlife managers focus outreach efforts on providing local residents with general information about black bears, as well as information pertinent to minimizing the potential for human–black bear conflict.  相似文献   
119.
While various energy-producing technologies have been analyzed to assess the amount of energy returned per unit of energy invested, this type of comprehensive and comparative approach has rarely been applied to other potentially limiting inputs such as water, land, and time. We assess the connection between water and energy production and conduct a comparative analysis for estimating the energy return on water invested (EROWI) for several renewable and non-renewable energy technologies using various Life Cycle Analyses. Our results suggest that the most water-efficient, fossil-based technologies have an EROWI one to two orders of magnitude greater than the most water-efficient biomass technologies, implying that the development of biomass energy technologies in scale sufficient to be a significant source of energy may produce or exacerbate water shortages around the globe and be limited by the availability of fresh water.  相似文献   
120.
It is widely accepted that improving the sustainability of seafood production requires efforts to reverse declines in global fisheries due to overfishing and to reduce the impacts to host ecosystems from fishing and aquaculture production technologies. Reflective of on-going dialogue amongst participants in an international research project applying Life Cycle Assessment to better understand and manage global salmon production systems, we argue here that such efforts must also address the wider range of biophysical, ecological, and socioeconomic impacts stemming from the material and energetic throughput associated with these industries. This is of particular relevance given the interconnectivity of global environmental change, ocean health, and the viability of seafood production in both fisheries and aquaculture. Although the growing popularity of numerous ecolabeling, certification, and consumer education programs may be making headway in influencing Western consumer perceptions of the relative sustainability of alternative seafood products, we also posit that the efficacy of these initiatives in furthering sustainability objectives is compromised by the use of incomplete criteria. An emerging body of Life Cycle Assessment research of fisheries and aquaculture provides valuable insights into the biophysical dimensions of environmental performance in alternative seafood production and consumption systems, and should be used to inform a more holistic approach to labeling, certifying, and educating for sustainability in seafood production. More research, however, must be undertaken to develop novel techniques for incorporating other critical dimensions, in particular, socioeconomic considerations, into our sustainability decision-making.  相似文献   
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