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111.
Aeolidiella stephanieae is a stenophagous tropical nudibranch that feeds exclusively on glass anemones of the genus Aiptasia. These sea anemones usually harbour endosymbiotic photosynthetic dinoflagellates that contribute to the nutrition of their host by providing photosynthetates, such as fatty acids (FA). The present work determined the effect of parental diets on the FA profile of A. stephanieae embryos by feeding breeding pairs of this nudibranch with either symbiotic or aposymbiotic A. pallida. Contrasting FA profiles, namely in the levels of palmitic acid (16:0) and docosahexaenoic acid (DHA, 22:6n-3), were recorded for both parental diets and egg masses produced by nudibranchs eating either symbiotic or aposymbiotic A. pallida. Noteworthy effects of parental dietary FAs on egg masses were also observed, particularly for DHA, which is mainly synthetized by the endosymbionts of A. pallida. Additionally, the present study also highlights how bleaching events may promote cascading effects on the nutrition of marine species with a stenophagous diet, such as A. stephanieae.  相似文献   
112.
Larval decapods are commonly produced in captivity and employed in experiments to evaluate interspecific physiological and biochemical differences. Currently, it is still unknown if different decapod species provided a common diet and exposed to identical abiotic conditions produce newly hatched larvae (NHL) with similar fatty acid (FA) profiles. This study analyzed the FA composition of NHL from five marine shrimp species (Lysmata amboinensis, L. boggessi, L. debelius, L. seticaudata and Rhynchocinetes durbanensis) fed a common diet and stocked at constant temperature. FA profiles of NHL differed significantly within and among genera. NHL from species unable to molt from zoea I to zoea II in the absence of food (L. amboinensis, L. debelius and R. durbanensis) displayed the lowest FA contents. Researchers must be aware that providing a common diet to different species, even if closely related, may not standardize the FA profile of NHL produced in captivity.  相似文献   
113.
One of the traditional livelihood practices of indigenous Tagbanuas in Palawan, Philippines is wild honey hunting and gathering from the giant honey bee (Apis dorsata F.). In order to analyze the linkages of the social and ecological systems involved in this indigenous practice, we conducted spatial, quantitative, and qualitative analyses on field data gathered through mapping of global positioning system coordinates, community surveys, and key informant interviews. We found that only 24% of the 251 local community members surveyed could correctly identify the giant honey bee. Inferential statistics showed that a lower level of formal education strongly correlates with correct identification of the giant honey bee. Spatial analysis revealed that mean NDVI of sampled nesting tree areas has dropped from 0.61 in the year 1988 to 0.41 in 2015. However, those who correctly identified the giant honey bee lived in areas with high vegetation cover. Decreasing vegetation cover limits the presence of wild honey bees and this may also be limiting direct experience of the community with wild honey bees. However, with causality yet to be established, we recommend conducting further studies to concretely model feedbacks between ecological changes and local knowledge.  相似文献   
114.
The Bormida River Basin, located in the northwestern region of Italy, has been strongly contaminated by the ACNA chemical factory. This factory was in operation from 1892 to 1998, and contamination from the factory has had deleterious consequences on the water quality, agriculture, natural ecosystems and human health. Attempts have been made to remediate the site. The aims of this study were to use high-resolution satellite images combined with a classical remote sensing methodology to monitor vegetation conditions along the Bormida River, both upstream and downstream of the ACNA chemical factory site, and to compare the results obtained at different times before and after the remediation process. The trends of the Normalised Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI) along the riverbanks are used to assess the effect of water pollution on vegetation. NDVI and EVI values show that the contamination produced by the ACNA factory had less severe effects in the year 2007, when most of the remediation activities were concluded, than in 2006 and 2003. In 2007, the contamination effects were noticeable up to 6 km downstream of the factory, whereas in 2003 and 2006 the influence range was up to about 12 km downstream of the factory. The results of this study show the effectiveness of remediation activities that have been taking place in this area. In addition, the comparison between NDVI and EVI shows that the EVI is more suitable to characterise the vegetation health and can be considered an additional tool to assess vegetation health and to monitor restoration activities.  相似文献   
115.
116.
An objective function based on geostatistical variance reduction, constrained to the reproduction of the probability distribution functions of selected physical and chemical sediment variables, is applied to the selection of the best set of compliance monitoring stations in the Sado river estuary in Portugal. These stations were to be selected from a large set of sampling stations from a prior field campaign. Simulated annealing was chosen to solve the optimisation function model. Both the combinatorial problem structure and the resulting candidate sediment monitoring networks are discussed, and the optimal dimension and spatial distribution are proposed. An optimal network of sixty stations was obtained from an original 153-station sampling campaign.  相似文献   
117.
The concentrations of 17 polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in sediment and key species as an initial investigation on PCDD/Fs and dl-PCBs contamination in the Mondego estuary (Portugal). The results demonstrated that the values of the total PCDD/Fs (∑PCDD/Fs) concentrations were considerably lower than those of the sum of dl-PCBs (∑dl-PCBs) in all the studied samples. Regarding the contribution of individual congeners, OCDD was the predominant PCDD/F and the mono-ortho PCB 118 and PCB 105 were the dominant PCBs in the majority of the samples. Our results suggest that PCDD/Fs and PCBs behave quite differently along the aquatic food web: ∑PCDD/Fs concentrations were lower in higher trophic-level organisms with fish presenting a distinct PCDD/Fs congeners profile; on the contrary, the higher ∑dl-PCBs values were found in upper-level biota, although not exclusively, and quite similar dl-PCBs congener profiles were observed in nearly all the studied species.  相似文献   
118.
The emission of radon gas in regions of geological faults, during the radioactive decay of uranium and thorium, results in the formation of lead isotopes 210Pb, 208Pb, 207Pb and 206Pb. As a consequence, the lead contamination in the soil poses a hazard to humans through ingestion of food, contaminated water, and even by direct contact with the soil contaminant. So far the relationship between the occurrence of geological faults and soil Pb contamination has not been established. Here, we studied lead in soils of regions with geological faults and their possible relationship with radon emissions. Soils were sampled from Presidente Prudente located in the far west of São Paulo State, Brazil. The region has strong evidence of the existence and direction of geological faults at depths of approximately 200 m. Soil sampling was done according to the USEPA 3050 method. Total lead was quantified by anodic stripping voltammetry. Results show that the total Pb concentration increases systematically with soil depth. This finding is explained by the fact that the lead originates from radon emissions. Pearson correlation analysis further proves a relationship of the nuclear track density obtained with CR-39 detectors, and mean Pb levels within each soil profile. Overall, our findings should improve risk evaluation of Pb contamination derived from radon emission and geological faults.  相似文献   
119.
There are few methods that are suitable for assessing the sustainability of companies and supply chains in an integrated way, taking into consideration the economic, social and environmental dimensions. This paper proposes a framework for assessing the sustainability of individual companies and their corresponding upstream supply chain. The framework consists of a set of steps to evaluate the sustainability of both the individual company and their upstream supply chain. The linear aggregation technique is suggested to combine the set of indicators from the economic, environmental and social dimensions of sustainability into a unique value, giving rise to a composite index for the company and corresponding supply chain. The proposed framework represents a contribution in the area of index construction and could be used as a valuable component of sustainability reporting and sustainability management practices. It also represents an important benchmarking tool, offering managers the possibility of identifying the supply chain partners that are best and worst performers in terms of sustainability while at the same time making it possible to improve company performance. Managers can adjust their company’s behaviour according to their sustainability index score and improve economic, social and environmental performance.  相似文献   
120.
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