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11.
The aim of this study was to validate lichens as biomonitors of PAH atmospheric deposition; for that, an inter-comparison between the PAH profile and concentrations intercepted in lichens with those of air, soil and pine needles was performed. The study was conducted in a petro-industrial area and the results showed that PAH profiles in lichens were similar to those of the air and pine needles, but completely different from those of soils. Lichens accumulated higher PAH concentrations when compared to the other environmental compartments and its concentrations were significantly and linearly correlated with concentrations of PAHs in soil; we showed that a translation of the lichen PAHs concentrations into regulatory standards is possible, fulfilling one of the most important requirements of using lichens as biomonitors. With lichens we were then able to characterize the air PAHs profile of urban, petro-industrial and background areas.  相似文献   
12.
Data from ten years of integrated monitoring were used here to evaluate whether pine needles are a feasible tool for an assessment of long-term trends of the atmospheric contamination. Pine needles collected once a year were compared to high volume air samples collected for 24 h, every 7 days, and passive air samples integrated over 28-day periods. Results showed the same concentration patterns of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) captured in needles and high volume samples. Passive air samplers were less efficient in sampling the particle-bound compounds. Theoretical air volume equivalent to each needle sample (VEQ) was calculated as a ratio of the needle concentration over the mean air concentration. Results indicated different equivalent volumes for PAHs and organochlorines, possibly due to the faster degradation rates of PAHs in needles. The most important finding is that in the long term a needle monitoring gives very similar information on temporal trends of the atmospheric pollution as does a high volume air monitoring.  相似文献   
13.
ABSTRACT: Rosgen analysis, developed for assessing channel stability in streams from the western United States, is applied to the Oswego River watershed in the New Jersey Pine Barrens. The Rosgen method requires calibration to local conditions due to the impact of peat substrates on channel morphology. In particular, the presence of peat induces low width to depth ratios and greater channel confinement, reversing typical downstream morphologic trends observed in other rivers. Therefore peat is added to those substrates already evaluated by Rosgen. A consistent sequence of Rosgen stream types develops along the Oswego River and its tributaries created by spatially overlapping processes of water table emergence, peat development, and channel formation. This sequence delineates a “natural” transition of stream channel morphology downslope through the watershed. First, as the water table reaches the surface of dry sloughs, Sphagnum growth is stimulated and peat substrates result. These substrates have lower permeability than the underlying gravelly sands. Next, surface runoff, through braided pathways over the peat, eventually erodes mainly anastomosing channels into the peat. Finally, single‐thread channels develop in underlying gravelly sands further downslope. This downslope sequence, expressed as Rosgen stream types, begins generally with DA7 streams arising from dry sloughs. These pass to E7, C7 or DA5 stream types that in turn pass to B5c, C5 and C4 stream types. Departures from the “natural” stream type sequence occur along the course of the Oswego and its tributaries due to human activities such as the construction of dams, bridges and drainage ditches, stream bank erosion at streamside camping and picnic areas and the clear‐cutting of adjacent stands of Atlantic white cedar.  相似文献   
14.
The distribution of environmental pollutant, sulphur, over Kano municipality was monitored on the basis of the chemical analysis of Scots Pine (Pinus sylvestris L.) needles collected from randomly selected sampling points over the period 1995–1996. Of the five zones in which the municipal area was subdivided, two could be regarded as least polluted, two as moderately polluted and one zone as heavily polluted. The mean value of all measurements in the metropolis amounted to 1940 gg–1 S with a co-efficient of variation of 38 percent.  相似文献   
15.
A stand-scale forest model has been developed that dynamically simulates, besides carbon (C) and water (H2O) fluxes, wood tissue development from physiological principles. The forest stand is described as consisting of trees of different size cohorts (for example, dominant, co-dominant and suppressed trees), either of the same or of different species (deciduous or coniferous). Half-hourly C and H2O fluxes are modeled at the leaf, tree and stand level. In addition to total growth and yield, the model simulates the daily evolution of tracheid or vessel biomass and radius, parenchyma and branch development. From these data early and latewood biomass, wood tissue composition and density are calculated. Simulation of the labile C stored in the living tissues allows for simulation of trans-seasonal and trans-yearly effects, and improved simulations of long-term effects of environmental stresses on growth. A sensitivity analysis was performed to indicate the main parameters influencing simulated stem growth and wood quality at the tree and stand level. Case studies were performed for a temperate pine forest to illustrate the main model functioning and, more in particular, the simulation of the wood quality. The results indicate that the ANAFORE model is a useful tool for simultaneous analyses of wood quality development and forest ecosystem functioning.  相似文献   
16.
In this study the influence of environmental conditions, most likely prevailing in filter beds used for intermittently discharged pollutant streams such as landfill leachate and storm water, on the stability of the heavy metal-filter complex was investigated for 2 filter materials; non-treated and urea treated pine bark, using leaching experiments. The metal-filter complex stability was higher for urea treated than for non-treated pine bark and dependent on the metal adsorbed. The type of environmental condition applied was of less importance for the extent of leaching.  相似文献   
17.
Ok G  Ji SH  Kim SJ  Kim YK  Park JH  Kim YS  Han YH 《Chemosphere》2002,46(9-10):1351-1357
The atmospheric contamination levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were evaluated from the analysis of pine needles in South Korea. Pine needles were collected from 30 sampling points at five main cities in South Korea (Busan, Daegu, Gwangju, Changwon and Jeju island). The highest concentrations of PCDDs/DFs (2.19–26.88 pg I-TEQ/g of dry weight) were measured at Busan, where is the city of the highest population density and traffic volume among five cities. The lowest concentration was detected at Jeju with 0.62 pg I-TEQ/g dry weight, suggesting Jeju could be an environmental background area in Korea. The dominant homologues of PCDDs/DFs in pine needles were the lower chlorine-substituted compounds such as tetra CDDs and CDFs, and the distribution ratios of PCDDs/DFs decreased with increase of the number of chlorine substituents. Homologue profiles of pine needle samples were similar to PCDDs/DFs profiles of the vapor phase in the ambient air, and thus the pine needles absorbed the vapor phase of PCDDs/DFs from air. Results suggested that pine needles could be used as an indicator of the atmospheric contamination for PCDDs/DFs in Korea.  相似文献   
18.
Incubation temperature in ectothermic vertebrates affects incubation periods, and in some reptiles it affects sex ratios and behavior. I present evidence that incubation temperature affects emergence and post-hatching behavior of pine snakes (Pituophis melanoleucus) that could influence survival in the weeks before hibernation. Hatchlings incubated at low temperatures remained in the nest longer, had fewer alternate nest openings, and fewer underground tunnels to hide in than did hatchlings from warmer temperatures. These conditions could render hatchlings from low-temperature nests more vulnerable to predation because, if a nest is opened, they are not inside tunnels where they would be protected. Hatchlings from nests incubated at low temperatures took longer to find shade during a thermoregulation test, and were less likely to move about in search of other cover than were those from higher-incubation-temperature artificial nests. Similarly, hatchlings from nests with low incubation temperatures were less responsive to a predatory stimulus and had a longer latency to strike than other hatchlings. Taken together, hatchlings from nests with low incubation temperatures might be less able to avoid predators and find shade than those from nests incubated at higher temperatures, and thus could be expected to have lower survival in nature. Received: 21 July 1997 / Accepted after revision: 15 February 1998  相似文献   
19.
Cumulative effects assessment (CEA) in Canada is in dire straits. Despite a huge amount of talk and a flurry of developmental activity associated with CEA concepts, it has not lived up to its glowing promise of helping to achieve sustainability of diverse valued ecosystem components. This article aims to articulate that failure, to examine it in terms of six major problems with CEA, and to propose solutions. The six problem areas include (1) application of CEA in project-level environmental impact assessments (EIAs), (2) an EIA focus on project approval instead of environmental sustainability, (3) a general lack of understanding of ecologic impact thresholds, (4) separation of cumulative effects from project-specific impacts, (5) weak interpretations of cumulative effects by practitioners and analysts, and (6) inappropriate handling of potential future developments. We advocate improvements not only within the purview of project-specific EIAs, but also mainly in the domain of region-scale CEAs and regional environmental effects frameworks (or perhaps land use planning). Only then will the CEA begin to approach the promise of securing sustainability of valued ecosystem components.  相似文献   
20.
Samples of soil, sediment and pine needles from the Reggio Emilia area were analysed in order to estimate the environmental pollution caused by an MSWI. PCDD/PCDF, PCB, PAH and metals were analysed in the collected samples. The data obtained showed relatively low pollution levels. Indeed, the PCDD/PCDF and PCB data were comparable to the values usually found in the grazing areas of the European Union countries. Metal concentrations in soils and sediments may be related to local geological occurrences and to agricultural activities. PAH values are significantly lower than the limit values set by the Italian law.  相似文献   
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