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The paper addresses disaster risk of an urban community in a mega city, which experiences high risk to natural hazards. The Community Action Planning (CAP) tool is used in this case. It has been developed from five resilience dimensions (physical, social, economic, institutional, and natural), 25 parameters and 75 actions. A detailed CAP structured questionnaire survey was conducted with 89 Residential and Welfare Associations (RWAs) in East Delhi, India situated in three types of settlements: planned Delhi Development Authority (DDA) housing and societies, colonies, and urban villages. The result identifies and prioritizes 32 actions as important for all three settlements. The result shows both consistent and inconsistent responses from RWAs. To give some examples, parameter S3 is “tasks to reduce number of people suffer from water borne diseases after a disaster”. In response to this parameter, approximately 80% of total respondents prioritized action (A1), “promoting people to take preventive measures after a disaster”. It shows consistent response from all three settlements. However, parameter S5 is “tasks to improve the awareness and knowledge about threat and impact of disasters”. Approximately 40% of total respondents prioritized A1, “organizing training program for awareness and knowledge building”. This action was prioritized in planned DDA housing and societies (56%) as well as in colonies (52%). However, none of the respondents from urban villages prioritized this action. These responses show inconsistency in response to specific action. In addition, the study shows the potential impact of CAP process for other communities in cities that are experiencing disaster risks and impact of climate change.  相似文献   
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Habitat heterogeneity can generate intraspecific diversity through local adaptation of populations. While it is becoming increasingly clear that population diversity can increase stability in species abundance, less is known about how population diversity can benefit consumers that can integrate across population diversity in their prey. Here we demonstrate cascading effects of thermal heterogeneity on trout-salmon interactions in streams where rainbow trout rely heavily on the seasonal availability of anadromous salmon eggs. Water temperature in an Alaskan stream varied spatially from 5 degrees C to 17.5 degrees C, and spawning sockeye salmon showed population differentiation associated with this thermal heterogeneity. Individuals that spawned early in cool regions of the 5 km long stream were genetically differentiated from those spawning in warmer regions later in the season. Sockeye salmon spawning generates a pulsed resource subsidy that supports the majority of seasonal growth in stream-dwelling rainbow trout. The spatial and temporal structuring of sockeye salmon spawn timing in our focal stream extended the duration of the pulsed subsidy compared to a thermally homogeneous stream with a single population of salmon. Further, rainbow trout adopted movement strategies that exploited the multiple pulses of egg subsidies in the thermally heterogeneous stream. Fish that moved to track the resource pulse grew at rates about 2.5 times higher than those that remained stationary or trout in the reference stream with a single seasonal pulse of eggs. Our results demonstrate that habitat heterogeneity can have important effects on the population diversity of dominant species, and in turn, influence their value to species that prey upon them. Therefore, habitat homogenization may have farther-reaching ecological effects than previously considered.  相似文献   
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The use of soluble PO4(3-) and lime as a heavy metal chemical stabilization agent was evaluated for mine tailings from Leadville, Colorado. The tailings are from piles associated with the Wolftone and Maid of Erin mines; ore material that was originally mined around 1900, reprocessed in the 1940s, and now requires stabilization. The dominant minerals in the tailings are galena (PbS), cerrusite (PbCO3), pyromorphite (Pb5(PO4)3Cl), plumbojarosite (Pb0.5Fe3(SO4)2(OH)6), and chalcophanites ((Pb,Fe,Zn,Mn)Mn2O5 x 2H2O). The tailings were treated with soluble PO4(3-) and lime to convert soluble heavy metals (principally Pb, Zn, Cu, Cd) into insoluble metal phosphate precipitates. The treatment process caused bulk mineralogical transformations as well as the formation of a reaction rind around the particles dominated by Ca and P. Within the mineral grains, Fe-Pb phosphosulfates, Fe-Pb sulfates (plumbojarosite), and galena convert to Fe-Ca-Pb hydroxides. The Mn-Pb hydroxides and Mn-(+/-Fe)-Pb hydroxides (chalcophanites) undergo chemical alteration throughout the grains during treatment. Bulk and surface spectroscopies showed that the insoluble reaction products in the rind are tertiary metal phosphate (e.g. (Cu,Ca2)(PO4)2) and apatite (e.g. Pb5(PO4)3Cl) family minerals. pH-dependent leaching (pH 4,6,8) showed that the treatment was able to reduce equilibrium concentrations by factors of 3 to 150 for many metals; particularly Pb2+, Zn2+, Cd2+, and Cu2+. Geochemical thermodynamic equilibrium modeling showed that apatite family and tertiary metal phosphate phases act as controlling solids for the equilibrium concentrations of Ca2+, PO4(3-) Pb2+, Zn2+, Cd2+, and Cu2+ in the leachates during pH-dependent leaching. Both end members and ideal solid solutions were seen to be controlling solids.  相似文献   
215.
The article advances the hypothesis that the seasonal and inter‐annual variability of rainfall is a significant and measurable factor in the economic development of nations. An analysis of global datasets reveals a statistically significant relationship between greater rainfall variability and lower per capita GDP. Having established this correlation, we construct a water resources development index that highlights areas that have the greatest need for storage infrastructure to mitigate the impacts of rainfall variability on water availability for food and basic livelihood. The countries with the most critical infrastructure needs according to this metric are among the poorest in the world, and the majority of them are located in Africa. The importance of securing water availability in these nations increases every day in light of current population growth, economic development, and climate change projections.  相似文献   
216.
Weekly measurements of chemical composition were made at four sampling sites on the Lea River (Spain) between July 1985 and August 1986. at two stations there were gauging-weirs for stream discharge monitoring. Conductivity, pH, alkalinity, silicon, calcium, magnesium, sodium, potassium, ammonia, nitrate, sulphate, chloride, reactive phosphate, and total phosphate, were recorded in each site.

Results were analysed using multiple regression techniques to study the relationship between flow and chemical components.

Conductivity, alkalinity, calcium, magnesium and sulphate were strongly related to flow, decreasing in concentration with increased flow. Ammonia, potassium, reactive phosphate and total phosphate varied most widely, with peaks at times of heavy rainfall. Nitrate increased at times of high discharge, with little variation between sampling points. Silicon decreased in summer and autumn in the lower catchment area whilst chloride and sodium were higher in the lower catchment of the River Lea.  相似文献   
217.
Environmental Science and Pollution Research - Oil sludge washing (OSW) with surfactants and co-solvents is used to recover the oil, and this process leaves some residuals (sediments and surfactant...  相似文献   
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Within a Federal Environmental Agency research project to develop a biological test for hormone-mimetic compounds using the freshwater snail Marisa cornuarietis, the effects of the suspected xenoestrogenic substance bisphenol A (BPA), not only on freshwater but also on marine prosobranch snails, were investigated. For the laboratory experiments the ramshorn snail Marisa cornuarietis and the ovoviviparous snail Potamopyrgus antipodarum were considered as freshwater species and two marine prosobranchs, the netted whelk Nassarius reticulatus and the dog whelk Nucella lapillus, were additionally employed. N. reticulatus, as a typical sediment-living species, was exposed via artificial sediments, while the three other prosobranchs were exposed via water. The test series with Marisa cornuarietis covered a nominal concentration range between 1 and 100 μg BPA/l in a 5 month experiment with adult snails and a complete life cycle test for 12 months. Additionally, a third test in the nominal range between 0.05 and 1 μg BPA/l (measured: 0.0079–0.404 μg/l) was performed with adults snails for 6 months. In these experiments, BPA induced a complex syndrome of physiological and morphological alterations in female Marisa referred to as the induction of ‘superfemales’. Affected specimens were characterised by the formation of additional female organs, an enlargement of the accessory pallial sex glands, gross malformations of the pallial oviduct section resulting in an increased female mortality, and a massive stimulation of oocyte and spawning mass production. For these tests, an LOEC of 48.3 ng/l, an NOEC of 7.9 ng/l and an EC10 of 13.9 ng/l were calculated. Superfemales occurred also in the BPA exposure experiment with the other snail species, but comparable oviduct malformations as in Marisa were not found, probably due to species differences in the gross anatomical structure of the pallial oviduct. During the 9 week test with Potamopyrgus antipodarum in the nominal concentration range between 1 and 100 μg/l, BPA induced an enhancement of embryo production even in the sexual repose phase of the reproductive cycle. A characteristic inverted U-type concentration response relationship was found. Nassarius reticulatus was exposed via BPA-spiked artificial sediments (nominal concentration range: 10–1000 μg/kg dry wt.) for 3 months. BPA exhibited a significant and concentration dependent uterotrophic effect which could be detected not only by an enlargement but also by a weight increase of the accessory pallial gland complex in the pallial oviduct section. Adult Nucella lapillus were tested for three months in the laboratory in a nominal concentration range between 1 and 100 μg BPA/l. Superfemales in the dog whelk were also characterised by enlarged accessory pallial sex glands and an enhancement of egg production, but the test compound also affected the males in this species. A lower percentage of exposed specimens had ripe sperm stored in their vesicula seminalis and male Nucella exhibited a reduced length of penis and prostate gland when compared to the control. Because statistically significant effects were observed already at the lowest nominal test concentration (1 μg/l), it can be assumed that even lower concentrations may have a negative impact on the snails. The results show that prosobranch snails are affected by BPA at lower concentrations compared to other systematic taxa in the animal kingdom. Consequently, it has to be claimed that the results of these experiment have to be considered for the current EU risk assessment for BPA in order to achieve a sufficient protection of wildlife in aquatic ecosystems.  相似文献   
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