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101.
Structural physical habitat attributes include indices of stream size, channel gradient, substrate size, habitat complexity, and riparian vegetation cover and structure. The Environmental Monitoring and Assessment Program (EMAP) is designed to assess the status and trends of ecological resources at different scales. High-resolution remote sensing provides unique capabilities in detecting a variety of features and indicators of environmental health and condition. LIDAR is an airborne scanning laser system that provides data on topography, channel dimensions (width, depth), slope, channel complexity (residual pools, volume, morphometric complexity, hydraulic roughness), riparian vegetation (height and density), dimensions of riparian zone, anthropogenic alterations and disturbances, and channel and riparian interaction. Hyperspectral aerial imagery offers the advantage of high spectral and spatial resolution allowing for the detection and identification of riparian vegetation and natural and anthropogenic features at a resolution not possible with satellite imagery. When combined, or fused, these technologies comprise a powerful geospatial data set for assessing and monitoring lentic and lotic environmental characteristics and condition.  相似文献   
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Anthropogenic impacts on biodiversity can lead to biotic homogenization (BH) and biotic differentiation (BD). BH is a process of increasing similarity in community composition (including taxonomic, functional, and phylogenetic components), whereas BD is a process of decreasing similarity over space and time. Here, we conducted a systematic review of BH and BD in plant communities in tropical and subtropical forests to identify trends and knowledge gaps. Our bibliometric search in the Web of Science returned 1989 papers, of which 151 matched our criteria and were included in the analysis. The Neotropical region had the largest number of articles, and Brazil was the most represented country with 92 studies. Regarding the type of change, homogenization was more frequent than differentiation (noted in 69.6% of publications). The taxonomic diversity component was measured more often than functional and phylogenetic diversity components. Most studies (75.6%) assessed homogenization and differentiation based on a single observation in time; as opposed to few studies that monitored plant community over multiple years. Forest fragmentation was cited as the main determinant of homogenization and differentiation processes (57.2% of articles). Our results highlight the importance of evaluating community composition over time and more than taxonomic components (i.e., functional and phylogenetic) to advance understanding of homogenization and differentiation. Both processes were scale dependent and not mutually exclusive. As such, future research should consider differentiation as a potential transition phase to homogenization and that potential differences in both processes may depend on the spatial and temporal scale adopted. Understanding the complexity and causes of homogenization and differentiation is essential for biodiversity conservation in a world increasingly affected by anthropogenic disturbances.  相似文献   
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Aina R  Palin L  Citterio S 《Chemosphere》2006,65(4):666-673
Polycyclic aromatic hydrocarbons (PAHs) are among the most dangerous environmental contaminants due to their toxic, carcinogenic and mutagenic effects. Although there are many data in literature that detail the effects of PAHs on animals, little is known about their action on higher plants which are often used as bioindicators. The aim of the present study was to evaluate the genotoxicity of two different PAHs, benzo[a]pyrene (BaP) and naphthalene (Naph), on Trifolium repens L. Clover plants were exposed to soil which had been artificially contaminated with three concentrations of BaP (5, 10 and 20 microg g-1) or Naph (25, 50 and 100 microg g-1). After 15 days, changes in the DNA content and sequence of roots and shoots were evaluated by flow cytometry (FCM) and amplified fragment length polymorphism (AFLP). Root and shoot dry weight were also determined to assess plant growth. Results showed that BaP and Naph were both genotoxic for white clover, inducing significant changes in root and shoot DNA sequence. Damage was more severe in the root than in the shoot suggesting that the translocation of these compounds and their genotoxic metabolites was limited. Ploidy alterations were not detected and the extent of damage caused by all the tested PAH concentrations was not sufficient to affect plant development.  相似文献   
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The literature was reviewed in order to determine the variables likely to be important in forecasting thunderstorms. A stepwise discriminant analysis was performed on these variables to determine those significantly related to thunderstorm occurrence. Eight variables were selected. These were then used to produce a forecasting equation by means of the linear discriminant analysis technique. This equation was then tested against the Showalter and Total Totals indexes for forecasting skill, and was found to have higher skill.  相似文献   
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This article is about Total Quality Management and its relationship to corporate environmental affairs. As the TQM movement expands, the commitment to continuous quality improvement, customer satisfaction, and collaborative, team-oriented workplaces is finding new applications. Just as the success of Federal Express, AT&T, and other winners of the Malcolm Baldrige National Quality Award shows that Total Quality Management can transform a business, we also are learning of successes companies are having applying TQM principles to environmental management. Our experience with TQM and environmental management at Coors Brewing Company is in the area of pollution prevention. In addition to our brewing operations, we also operate the country's largest aluminum can manufacturing plant, where we produce 4 billion cans a year, a separate facility that makes the can tops, a glass bottle manufacturing plant, and various support facilities. In all, we have some 7,000 employees, and building a commitment to pollution prevention in an operation of that size requires much more than just adopting quality principles. In this article we show how it also means understanding how those principles will mesh with the corporate culture. What we found is that before TQM can begin its magic, a company must review its own culture to see how problems have traditionally been solved and how challenges have been met.  相似文献   
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