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361.
Environmental Science and Pollution Research - Anthropogenic land use change (ALUC) satisfies human needs but also impacts aquatic ecosystems. Aquatic ecosystems are intrinsically linked with...  相似文献   
362.
Environmental Science and Pollution Research - Some environmental factors are associated with an increased risk of multiple sclerosis (MS). Air pollution could be a main one. This study was...  相似文献   
363.
This paper focused on the past shoreline change rates along the coastal plain of the Volturno River, in southern Italy, western Mediterranean. A wide database comprising historical maps, aerial photographs, topographic sheets, bathymetric data was used to extract the spatial and temporal information of the coastlines at seven time points. Coastline displacement was calculated for two successive time points and relative surface variation (accretion and erosion) was estimated as well as minimum and maximum accretion/erosion linear values and rates. The surface variation analysis has revealed that the studied coast can be considered homogeneous since the 1970s, whereas it exhibits a variety of shoreline evolutionary trends after that time period. Timing and causes of trends and rates of variation were detected. Based on the estimated shoreline change rates, an appropriate morhodynamic one-line model was applied to predict evolutionary scenarios also in presence of port and defence works. The results obtained strongly emphasize that a successful coastal management requires a constant monitoring of the human-induced changes to account for the variability of rates over time.  相似文献   
364.
Environmental Science and Pollution Research - This study aimed to use bioassays (single and multispecies) with organisms from different trophic levels to assess soil quality in reclaimed coal...  相似文献   
365.
Environmental Science and Pollution Research - Microplastic pollution has become a global concern due to its distribution, high abundance, and negative impacts on aquatic ecosystems. These...  相似文献   
366.
Brown  Keith S.  Trigo  José Roberto 《Chemoecology》1994,5(3-4):119-126
Summary As recognized by Miriam Rothschild as early as the 1960s and repeatedly emphasized in her papers, the use, misuse, or non-use of plant allelochemicals by insects is extremely variable and difficult to predict, at many levels of time, space, and biological organization. Although certain patterns that reoccur have been important in the development of ecological theory, the optimization of cost-benefit equations involving two or three trophic levels, each with large numbers of individuals, populations, and species in erratic and complex interactions, produces unexpected and fascinating scenarios. The development of rapid colorimetric and chromatographic analyses for several types of plant allelochemicals, notably certain groups of alkaloids, cardiac and cyanogenic glycosides, phenolics, terpenes, and glucosinolates, has permitted a detailed investigation of the variation and flow of these substances in natural organisms and ecosystems. The results of these analyses, in our hands mostly for pyrrolizidine alkaloids (PAs), do not suggest a straightforward classical choice by the aposematic insect to simply sequester or synthesize its defences. Rather, they reveal a confusing variety of diffuse and complex patterns that become increasingly closer to chaos as they are multiplied across structures, species, sexes, stages, sites, seasons, and selective regimes. We present a model reflecting results of analyses at this chemoecological interface. Depending upon an initial option, involving the recognition (or not) of a plant allelochemical, the herbivore will face thereafter options to ingest it (or not), and then to tolerate and absorb (or detoxify and excrete), modify (or not), passively, actively or selectively accumulate, turn over (or not), distribute (or concentrate), and use this compound in a variety of growth, defense, or reproductive functions. The herbivore can also quantitatively or qualitatively regulate the intensity or dispersion of its attack on the plant tissues, in order to modify feedback loops of selection on the plant and its chemicals which exist in most of the earlier steps, or those with its predators and parasites that occur in the later ones. Options that lead to mutualism through positive feedback loops will tend to accumulate and become rapidly fixed by natural selection. Additional variations and anomalies such as automimicry, chemical mimicry, sexual dimorphism and communication, selective sequestration and passing-up of allelochemicals, special glands and structures, and synergism effects, are among the secondary complications of this model that have occupied much thought, time, experimental labor, and polemical space in chemical ecology journals and meetings. Examination of the tendencies and results at various points in the model can be used to explain these features and to make further predictions, plan experiments, and devise activity-based bioassays and new chemical analyses. These may lead some day to new and more robust visions of the major patterns of chemical transfer at this widespread and important natural interface.  相似文献   
367.
A historical explosives testing area harbored contamination as unevenly distributed solid particles within a contaminant-stained soil matrix. Particles larger than 3 mm diameter accounted for 96.4% of the explosives contamination. Independent sampling and analysis methods showed significant differences in contaminant estimations due to particulate explosives. We present a solvent-based sample averaging method designed to solve spatial heterogeneity problems resulting from the presence of contaminant particles.  相似文献   
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369.
A statistical study on the behavior of ground-level O3 concentration in different regions of a large urban area was carried out, with emphasis on pollutant gas concentrations and meteorological variables. The study was based on data generated by a network of measuring stations distributed throughout the S?o Paulo Metropolitan Area, in regions with different characteristics of traffic and economic activities. The combined application of principal component analysis and clustering techniques to data collected from 1997 until 2000 has led to the identification of implicit relationships between variables that have been associated with dominant processes related to O3 formation in different locations. Similarities between different regions of the city have also been detected and associated with local characteristics. The results indicate that the application of such statistical techniques to data collected in large urban areas enables the grouping of different regions according to their behavior in terms of O3 levels, as well as the identification of dominant processes in each group. These techniques are thus important in the planning of air pollution policies, especially in the case of O3, a pollutant that is not directly related to pollution levels alone.  相似文献   
370.
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