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Environmental Science and Pollution Research - The aim of this paper is to improve trend analysis for non-stationary Normalized Difference Vegetation Index (NDVI) time series (TS) over different...  相似文献   
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Exposure to residues of the nonsteroidal anti‐inflammatory drug (NSAID) diclofenac present in livestock carcasses has caused extensive declines in 3 Gyps vulture species across Asia. The carcass of a wild Eurasian Griffon Vulture (Gyps fulvus) was found in 2012 on an Andalucian (Spain) game hunting reserve and examined forensically. The bird had severe visceral gout, a finding consistent with Gyps vultures from Asia that have been poisoned by diclofenac. Liver and kidney samples from this Eurasian Griffon Vulture contained elevated flunixin (an NSAID) levels (median = 2.70 and 6.50 mg/kg, respectively). This is the first reported case of a wild vulture being exposed to and apparently killed by an NSAID outside Asia. It is also the first reported instance of mortality in the wild resulting from environmental exposure to an NSAID other than diclofenac. Caso de Sospecha de Envenenamiento por Flunixin de un Buitre Leonado en España  相似文献   
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Adult magpies Pica pica provide parasitic great spotted cuckoo Clamator glandarius nestlings with a diet very similar to that fed to their own chicks. In both naturally and experimentally parasitized nests, great spotted cuckoo chicks were fed at a higher rate than magpie chicks in the same nest. This preferential allocation of food by magpie parents to great spotted cuckoo chicks is consistent with the supernormal stimulus hypothesis, because this result implies that cuckoo chicks provide stronger stimuli for parental care than host chicks. Great spotted cuckoo chicks receive most of the food brought to the nest by the foster parents, because they exploit a series of stimuli which jointly (or sometimes individually) operate as a supernormal stimulus. This hypothesis predicts that if any stimulus is masked, the efficiency of the cuckoo in eliciting parental care will decrease. Here, we analyze experimentally the effects of two of these stimuli, preferential feeding of large nestlings and of nestlings with conspicuous palatal papillae. Firstly, when we experimentally introduced one medium-sized (7–9 days) cuckoo chick into an unparasitized magpie nest where the largest magpie chick was 12–15 days old, the cuckoo did not receive significantly more food than the average or the largest magpie chick. Secondly, when unparasitized nests were experimentally parasitized with a cuckoo chick that had its gape painted to mimic that of magpie chicks, the parasitic cuckoo received less food than the average magpie chick.  相似文献   
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The influence of environmental parameters (temperature, salinity and available food) on the condition, reproductive activity and biochemical composition of a native population of Ostrea edulis L. in San Cibran (Galicia, Spain) was studied between September 1988 and December 1989. Histological preparations of gonads showed that gametogenesis started when temperature was at its lowest in winter. The water temperature in San Cibran never fell low enough to interrupt it. Gametogenesis proceeded slowly and spawning took place in May–June, although the predicted time of ripening was early March. Salinity in San Cibran was relatively stable throughout the year; it did not seem to have any influence on gametogenesis. Available food appeared to be a very important factor in controlling gonad growth, once gametogenesis was initiated. The major concentration of suspended organic particulate matter was present in the spring at the time of rapid gonadal maturation. Only one spawning period was observed. Larvae were released when the food in the water was high. Seasonal changes in the main biochemical components of this oyster were determined for a standard individual. Lipids and carbohydrates presented a similar time-course whereas proteins were constant. When food was abundant, energy reserves were built up. Spawning produced a decrease in biochemical constituent levels, and recovery coincided with the phytoplankton bloom. The stored reserves, mainly lipids, were used to overcome a state of energy imbalance in late autumn associated with low food availability. Results show this oyster to be an opportunist organism which concentrates its reproductive effort during a short period of favourable conditions and which is directly dependent on nutritive availability in the environment.  相似文献   
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Hosts of brood parasites have evolved the ability to discriminate non-mimetic and even mimetic eggs, but not non-mimetic chicks. Here we demonstrate that the great spotted cuckoo Clamator glandarius does not provide its magpie Pica pica host with a super-normal stimulus that helps to avoid recognition, because single cuckoo chicks introduced into otherwise unparasitized magpie nests are not fed at a higher frequency than single magpie chicks introduced to parasitized magpie nests. Another series of experiments demonstrated that magpies have the ability to discriminate cuckoo chicks, mainly when these are introduced at the end of the nestling period, and especially when the cuckoo chick together with a magpie chick is presented to adult magpies outside the nest. This supports the idea that cuckoos exploit the obligatory reaction of magpies to feed all young that have been hatched in their nests and whose signatures they have learnt. Furthermore, the experimental cuckoo chicks in parasitized magpie nests were more likely to be accepted than they were in non-parasitized nests. This supports the hypothesis that magpies may learn to recognise their own nestlings as those present in the nest and may indicate that a comparison between cuckoo and magpie nestlings is the basis of discrimination.  相似文献   
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2 were sampled in order to verify the impact of these problems on groundwater. All samples were analyzed for major ions, and about 30 of them for fecal coliforms and heavy metals. Nineteen samples were selected for pesticide analyses. The average nitrate content was 80 mg/liter, eight times the regional background value. Fecal coliforms were detected in 60% of the analyzed samples. Zinc content and a high Cl/HCO3 ratio were observed in the surroundings of the solid waste disposal area. Moreover, lindane and heptachlor pesticides were detected in ten samples.  相似文献   
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A growing body of research indicates that the most biologically active PCB congeners and organochlorines are not the most abundant components in human and wildlife samples. As researchers attempt measurement on a wider pool of less abundant compounds, they inevitably face quantification problems. To address this problem and enhance comparability across studies, we propose a standardized approach to report organochlorines that is based on a reproducible method to determine the limit of quantification (LQ). Two statistical methods are incorporated into our approach, one by Gibbons termed the Alternative Minimum Level (AML), and one based on determining a region of stable relativestandard deviation in instrument response (RSD). We illustrate our approach using historical samples collected during the 1960s from a cohort of pregnant women enrolled in the Child Health and Development Study. The results are applicable to determining the LQ of any method, and are of utmost importance to environmental scientists conducting trace organic analyses of complex mixtures. Our results demonstrate that: (1) precision as measured by RSD is the most important criterion in determining LQ; (2) the AML routinely isolates a region of constant RSD; and (3) the precision of the instrument detector response as measured with pure standards locates the LQ applicable for real samples - that is, the true limits of quantification reside in the detector, not the matrix effects or analyte recoveries associated with real samples. A corollary of these findings is that bias due to matrix effects and analyte recoveries can be assessed separately from precision and LQdetermination. Previous approaches involved spiking matrix blanks to determine LQ, a problematic strategy for real world, complex matrices. We have now validated the use of pure standards in LQ determination, an approach that is practical and accessible to most analysts.  相似文献   
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