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101.
Environmental Science and Pollution Research - Studies have shown that domestic waste collectors are exposed to toxicants including infectious pathogens, which may be linked to their oral health...  相似文献   
102.
Given the importance of markets and fairs for the commerce of medicinal plants, an ethnobotanical study was undertaken at the Caruaru Fair (Pernambuco, northeastern Brazil) to compare the richness of species sold and their values of relative importance (RI) using two datasets collected with a 4-year interval. The seasonality of these plants?? supplies was also analyzed. The Caruaru Fair is located in the 18 de Maio Park. It covers an area 40,000?m2 and is used by merchants who sell several types of products, such as supplies, handicrafts, clay and aluminum utensils, shoes, clothes and medicinal plants. Semistructured interviews were carried out with the vendors who agreed to take part in the study in order to record which plants were sold and their respective indications. The plants were collected, and the species were determined. The information was analyzed with quantitative tools. A total of 169 plants were identified from both surveys, which were significantly different with regard to species richness (p?<?0.05) but did not vary in relation to species?? Relative Importance (p?>?0.05). In relation to the seasonality of the plant supply, habit may explain the lack of some species during certain periods of the year, as most of the absent plants are herbaceous. In terms of the species most sold locally, it was found that spontaneous tree species are well known and extensively commercialized.  相似文献   
103.
Although the concept of tropical birds as sedentary is pervasive, evidence suggests many are not. Our grasp of movement status in tropical birds is decidedly poor, but the successful long-term conservation of these birds depends on such information. Sedentariness will likely doom much tropical avian diversity, but increased vagility is a two-edged sword: beneficial in promoting immigration, but detrimental in that more than one habitat may be required. Birds requiring more than one habitat may be unable to locate a particular type as landscape modifications increase. Our long-term data set from the Sierra de Los Tuxtlas in southern Veracruz, México, reveals infrequent, large-scale movements in a local highland endemic. Wetmore's Bush-Tanager ( Chlorospingus ophthalmicus wetmorei) seems occasionally dependent upon lowland forests (now greatly diminished) as a refugium from temporarily unsuitable highlands. Our data and observations lead us to three conclusions: 1) assumptions of sedentariness in tropical birds should be made with extreme caution; 2) normal, but periodic phenomena may be easily overlooked, even in relatively long-term studies; and 3) missing such phenomena jeopardizes the success of any conservation plan because over the long term a population may be dependent upon refugia only occasionally occupied.  相似文献   
104.
The environmental performance evaluation (EPE) of organizations is becoming an autonomous management tool. The main goal of this research was to assess the state of EPE practice in the Portuguese defence sector, as a particular part of public services. A questionnaire survey was conducted involving all Portuguese military units that have a person in charge of environmental issues. The questionnaire was designed to assess: (i) the importance and drivers of EPE; (ii) the ISO 14031 knowledge and implementation; (iii) the knowledge and use of environmental indicators; (iv) the optimal format for indicators; and (v) the advantages and drawbacks of using environmental indicators. Despite various initiatives driving environmental practices in public organizations, most of that experience is only centred on an environmental management system, and EPE is quite a new issue. Nevertheless, general environmental performance evaluation is a growing reality and one in which Portuguese military units are taking an increasing interest. Overall respondents agree on the importance of measuring and communicating environmental performance related to their main missions and activities. The main drivers for EPE in military units are the prevention of health risks and compliance with regulations. However, to date, ISO 14031 and environmental performance indicators are almost unknown in the respondent military units. Among the three military branches, the Navy revealed the worst environmental performance evaluation knowledge, awareness and practice.  相似文献   
105.
Diflubenzuron (DFB) is an insecticide commonly used to control forest pests. The objectives of this study were to assess the effect of diflubenzuron on the development of Pinus pinaster seedlings and Pisolithus tinctorius under laboratory conditions and to study the possible protective role of this ectomycorrhizal fungus against the effects of diflubenzuron. In vitro experiments revealed that diflubenzuron inhibited fungal growth at all tested concentrations (0.01, 0.1, 1, 10 and 100 mg L?1). Root growth was inhibited at the two highest diflubenzuron concentrations. The activity of the antioxidant defence system of non-inoculated P. pinaster increased at 1 and 10 mg DFB kg?1 substrate, and inoculation increased the threshold to the highest concentration. The protective role of the ectomycorrhizal fungus was seen in the increase of CAT activity. This study revealed that despite causing no mortality, diflubenzuron has the ability to cause sub-lethal damage to P. pinaster. The disproportionate use of this insecticide may lead to higher amounts of its residues in soil and the biosphere, endangering trees, fungi and their symbiosis.  相似文献   
106.
An analytical procedure for the determination of Hg in otter (Lontra longicaudis) feces was developed, to separate fish scales for the identification of the animal diet. Samples were washed with ultra-pure water and the suspension was sampled and transferred for digestion. The solubilization was performed with nitric-perchloric acid mixture, and detection carried out by the atomic fluorescence spectrometry (AFS). The quality of the analytical procedure was assessed by analyzing in-house standard solutions and certified reference materials. Total Hg concentrations were in the range of 7.6-156 ng g(-1) (July 2004), 25.6-277 ng g(-1) (January 2005) and 14.6-744 ng g(-1) (May 2005) that is approximately the same order of magnitude for all samples collected in two reservoirs at the Tiete River, Brazil. Although Hg concentrations varied with sampling periods and diet, high levels were correlated to the percentage of carnivorous fish scales present in the otter feces.  相似文献   
107.
Long-term monitoring program of organisms is the most recommended for understanding changing processes on reefs. The video transect method presents advantages for that. Specialists state that it is important to make sure that the recorded coverage is always the same between campaigns, so that differences in results may be entirely attributed to environmental changes. This study aimed to test the capability of implementing this requirement through tracking simulation and its validity for monitoring the benthic communities of reefs using the video transect method. Ten transects 20 m long were established in Todos os Santos Bay coral reefs. Subsequent to the first transect capture, a second diver repeated the same track, simulating two different monitoring campaigns. Data were transformed and a matrix of similarity was generated using Bray–Curtis’ Index. ANOSIM analysis was performed to test the similarity of the ten transects and its repetitions. The result, R = 0.08 (P = 0.928), shows that reef monitoring using video transect, the way it is described in the literature, is appropriate, but it is important to consider some premises discussed in this work.  相似文献   
108.
Arsenic oxyanions, considered as priority pollutants, were removed from dilute aqueous solutions by sorption onto synthetic goethite, a typical inorganic adsorbent. Flotation was subsequently applied as an effective solid/liquid separation method. The combined process produced a foam concentrate, containing the arsenic-loaded goethite particles. The dispersed-air flotation technique was used for the generation of fine gas bubbles. The main parameters affecting the process were studied and promising results, in terms of arsenic removal and of goethite separation, were obtained.  相似文献   
109.
Seedlings of the salt secreting mangrove Avicennia marina were exposed to fumes of the volatile fraction of light Arabian crude oil (VFCO) under controlled conditions. Rates of salt secretion were determined in leaves fumigated for 0, 3, and 6 h under four different salinity levels (10, 20, 30, and 40 ppt). Studying the effect of these fumigation periods on stomatal resistance and transpiration was restricted to one salinity level (20 ppt). Opposite to salinity, increasing the fumigation period significantly reduced both salt secretion and transpiration with a significant increase in the stomatal resistance to gas diffusion. During the first day of recovery from fumigation stress, different stomatal oscillation patterns were observed in the treated plants. The amplitude of the oscillations increased with the duration of fumigation. as did the time required for stomatal recovery. Seedlings fumigated for 3 h started to recover within 48 h, while full recovery in seedlings fumigated for 6 h required almost twice that period. The apparent recovery process was evident in the damping off of the amplitude of stomatal oscillations during the measurements period. Data presented herein show that the exposure of mangrove seedlings to VFCO disturbs the normal functions of two major structures in the leaves, i.e. the stomata and the salt glands. The ecophysiological significance of these results was discussed in relation to previous studies.  相似文献   
110.
The GLEAMS (Groundwater Loading Effects of Agricultural Management Systems, Version 2.10) model was linked with a Geographical Information System (GIS) to evaluate the risk of nitrate pollution in an area of 230 km2 near Valencia (Spain). Under Mediterranean conditions, GLEAMS was calibrated and validated using results from field experiments on citrus orchards and vegetables grown in that area. A graphical user interface (GUI) was implemented in the GIS-model system to allow a non-specialist to run the model, and to represent simulation results as a thematic map. In order to execute the GLEAMS model, data must be grouped in five basic layers: four layers correspond to the base maps (soils, climate, land use, NO3 content in irrigation water), and the fifth layer corresponds to agricultural management practices, introduced in the system interacting to the GUI. To illustrate system capabilities. two rotations with crops in the vegetable area (potato/lettuce/onion/cauliflower, and artichoke/artichoke in 2 years rotation each), and orange trees in the citrus area, were simulated to determine the N leached in the study area. Pollution risk maps show that vegetable crops and areas irrigated with groundwater have the highest potential risk of groundwater nitrate pollution. Further analysis identified potato and artichoke (in the first year) to be the crops with the higher risk.  相似文献   
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