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51.
This paper examines local government and non‐governmental organisation (NGO) engagement in disaster response in the wake of the M/T Solar 1 oil spill in Guimaras, Western Visayas, Philippines, on 11 August 2006. It assesses the response activities of these two entities as well as the institutional factors that affected their interaction on the ground. Local government and NGO engagement was shaped by multi‐layered, overlapping, and oftentimes contending government‐designed response frameworks. Within these frameworks, government actors played the role of primary implementer and provider of relief, allowing them to determine who could be involved and the extent of their involvement. The absence of formal roles for NGOs in these frameworks not only undermines their ability to work in a setting where such institutional set‐ups are operational but also it reaffirms their ‘outsider’ status. This study of the Guimaras oil spill illustrates the complexity and the institutional difficulties inherent in disaster response and coordination in the Philippines.  相似文献   
52.
PCDDs, PCDFs and PCBs have been analysed in soil samples where waste electrical equipment has been burned directly on the ground in three locations of Burgos (Spain). High levels of PCDDs, PCDFs and PCBs were detected in the centre of combustion sites. The results show PCB levels between 0.824 and 1.240 μg/g, and PCDDs and PCDFs levels between 8.73–36.37 ng/g and 12.79–50.95 ng/g. The I‐TEF values between 2.96–9.15 for dioxins and furans indicate that these soils are heavily polluted and may represent a risk for human and animal health.  相似文献   
53.
Fernandez CW  Koide RT 《Ecology》2012,93(1):24-28
Ectomycorrhizal fungal tissues comprise a significant forest-litter pool. Ectomycorrhizal (EM) fungi may also influence the decomposition of other forest-litter components via competitive interactions with decomposer fungi and by ensheathing fine roots. Because of these direct and indirect effects of ectomycorrhizal fungi, the factors that control the decomposition of EM fungi will strongly control forest-litter decomposition as a whole and, thus, ecosystem nutrient and carbon cycling. Some have suggested that chitin, a component of fungal cell walls, reduces fungal tissue decomposition because it is relatively recalcitrant. We therefore examined the change in chitin concentrations of EM fungal tissues during decomposition. Our results show that chitin is not recalcitrant relative to other compounds in fungal tissues and that its concentration is positively related to the decomposition of fungal tissues. Variation existing among EM fungal isolates in chitin concentration suggests that EM fungal community structure influences C and nutrient cycling.  相似文献   
54.
To delineate the natural history of fetal multicystic dysplastic kidneys (MDKs), all cases that were prenatally detected in the Prenatal Diagnosis Center of the University of Virginia from September 1985 to 31 August 1988 were reviewed. All patients were followed through the Center with serial ultrasound evaluations at approximately 4-week intervals, and each liveborn infant was evaluated and followed by one of the authors (S.S.H.) Of the 14 cases detected, ten were detected in the second trimester, the earliest at 16·5 weeks' gestation. Of the nine fetuses with non-lethal disease, there were two cases in which the lesion remained unchanged during observation. Both had an initial diagnosis in the third trimester. In those cases diagnosed in the second trimester (7), all showed an initial increase in the size and number of cysts, followed by involutional changes either in utero (2) or in the neonatal period (3). Two infants had immediate surgical removal of the MDK, one because of respiratory compromise, and the other because of an uncertain diagnosis on renal scan. Abnormalities of the contralateral kidney were found in 7 of 14 fetuses. Five were lethal conditions. Associated non-renal abnormalities were common in bilateral MDK (80 per cent), but rare in unilateral MDK (11 per cent).  相似文献   
55.
Summary. Biological invasions are nowadays a major problem in ecology. Allelopathy has been shown to be involved in such invasions, but this mechanism has been little studied in France. The objectives of this study were to evaluate the allelopathic potential of Medicago arborea, an invasive species in the French Mediterranean region. Foliar extracts were tested on three target species (Lactuca sativa, Lepidium sativum and Linum strictum). We showed that Medicago arborea has high allelopathic potential to affect the growth and germination of other species. Yellow flax (Linum strictum), native to the invaded area, was the most sensitive of the tested plant species to foliar extracts of Medicago arborea. Our study pointed out the role of allelopathy in processes leading to biological invasion, and more generally in population dynamics.  相似文献   
56.
Environmental Science and Pollution Research - Organotin compounds, such as tributyltin (TBT), are environment contaminants that induce bioaccumulation and have potential toxic effects on marine...  相似文献   
57.
58.
Increased dissolved inorganic carbon (DIC) enhances the mobilization of metals and nutrients in soil solutions. Our objective was to investigate the mobilization of Al, Ca, Fe, and P in forest soils due to fluctuating DIC concentrations. Intact soil cores were taken from the O and B horizons at the Bear Brook Watershed in Maine (BBWM) to conduct soil column transport experiments. Solutions with DIC concentrations (~20–600 ppm) were introduced into the columns. DIC was reversibly sorbed and its migration was retarded by a factor of 1.2 to 2.1 compared to the conservative sodium bromide tracer, corresponding to a log K D?=???0.82 to ?0.07. Elevated DIC significantly enhanced the mobilization of all Al, Fe, Ca, and P. Particulate (>0.4 μm) Al and Fe were mobilized during chemical and flow transitions, such as increasing DIC and dissolved organic carbon (DOC), and resumption of flow after draining the columns. Calcium and P were primarily in dissolved forms. Mechanisms such as ion exchange (Al, Fe, Ca), ligand- and proton-promoted dissolution (Al and Fe), and ligand exchange (P) were the likely chemical mechanisms for the mobilization of these species. One column was packed with dried and sieved B-horizon soil. The effluent from this column had DOC, Al, and Fe concentrations considerably higher than those in the intact columns, suggesting that these species were mobilized from soil’s microporous structure that was otherwise not exposed to the advective flow. Calcium and P concentrations, however, were similar to those in the intact columns, suggesting that these elements were less occluded in soil particles.  相似文献   
59.
This work discusses the temporal variation of metal concentrations in a hypertrophic coastal lagoon located in the metropolitan area of Rio de Janeiro (Brazil). The lagoon watershed includes one of the mostly densely urbanized areas of the city but without industrial activities. Six sediment cores were collected in the lagoon between May and July 2003 and analyzed for the concentration of metals (Fe, Al, Mn, Zn, Pb, Cu, Cr, and Ni). Typical sedimentation rate was calculated as being 0.75 cm year???1 and was uniform for at least the past 70 years. Therefore, the alterations in the dynamics of the lagoon caused by changes in its watershed were clearly indicated in sediment cores. The construction of an artificial canal to the sea and the increasing urbanization and soil use changes were the major factors affecting metal accumulation in the lagoon sediments. Metals typical of anthropogenic urban sources (Pb, Zn, and Cu) showed increasing loads following urbanization.  相似文献   
60.
The BIODEP model in terms of atmosphere-lake interactions was developed. The model was applied to an oligotrophic, dimictic high altitude lake (Lake Redo, Pyrenees) for a range of polychlorinated biphenyl (PCB) congeners. High altitude lakes, which receive their contaminant inputs uniquely from the atmosphere through long-range atmospheric transport, provide ideal controlled environments for the study of the interactions between atmospheric depositional and water column biogeochemical processes. The BIODEP model was able to predict dissolved water concentrations and PCB accumulation in the lake sediment within a factor of 2. This shows that the BIODEP model captures the essential processes driving the sink of POPs in high altitude lakes and that POP occurrence in the lake is driven by direct atmospheric inputs with limited influence from the watershed. An important seasonal variability in water column concentrations is predicted which should have important implications in sampling strategies. Furthermore, it is shown that diffusive air-water exchange dominated the PCB dynamics in the lake, especially for the less chlorinated biphenyls.  相似文献   
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