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Environmental Science and Pollution Research - In this study, the essential oil (EO) from leaves of Croton linearis Jacq was extracted and characterized by GC/MS. The EO hydrophilic-lipophilic...  相似文献   
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Fungal symbioses affect the diversity, dynamics, and spatial patterns of trees in tropical forests. Their ecological importance is partly driven by their inherent patchiness. We used epifoliar fungi, a guild of common, benign, obligate, fungal symbionts of plants, as a model system to evaluate the relative importance of host phylogeny, host relative abundance, and microclimate on the three-dimensional distribution of plant-fungus symbioses. In parallel studies in rainforests in Panama and Australia, most epifoliar fungi were able to colonize several plant lineages but showed significant host preferences within the local plant community. More closely related plant species were not more likely to share fungal symbionts. Instead, fungal species were more likely to be shared by more abundant hosts, which supported a greater number and diversity of fungi. Environmental conditions strongly affected spatial distributions, with sites in the dark understory 2.5- to fourfold more likely to have epifoliar fungi than in the exposed forest canopy. In the understory, fungal incidence increased with canopy openness. Canopy trees supported only a subset of the fungal symbionts found in the understory, suggesting that adult trees are not reservoirs of these fungal symbionts for understory juveniles.  相似文献   
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Urbanization has rapidly increased in recent decades and the negative effects on biodiversity have been widely reported. Urban green areas can contribute to improving human well-being, maintaining biodiversity, and ecosystem services (e.g. pollination). Here we examine the evolution of studies on plant–pollinator interactions in urban ecosystems worldwide, reviewing also research funding and policy actions. We documented a significant increase in the scientific production on the theme in recent years, especially in the temperate region; tropical urban ecosystems are still neglected. Plant–pollinator interactions are threatened by urbanization in complex ways, depending on the studied group (plant or pollinator [generalist or specialist]) and landscape characteristics. Several research opportunities emerge from our review. Research funding and policy actions to pollination/pollinator in urban ecosystems are still scarce and concentrated in developed countries/temperate regions. To make urban green spaces contribute to the maintenance of biodiversity and the provision of ecosystem services, transdisciplinary approaches (ecological–social–economic–cultural) are needed.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01410-z) contains supplementary material, which is available to authorized users.  相似文献   
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To assess the health status of aquatic ecosystems, specialized tools and strategies are needed to study the changes induced in oceanic systems by human activity. The Gulf of Mexico has a tremendous ecological importance because of its biological diversity. The present paper defines baseline levels of blood metabolites and immune components for wild tropical populations of F. duorarum: an important shrimp species of the Gulf of Mexico. Osmotic pressure (OP), osmotic capability (OC), oxy hemocyanin (OxyHc), glucose, digestive gland glycogen, proteins, cholesterol, lactate, acylglycerols (AG) were used as indicators of physiological and nutritional status; phenoloxidase activity, quantification of hemocytes, as well as respiratory burst, were used to assess the immunological status. There were no differences between sexes in either live weight or physiological and nutritional conditions. Only total blood protein, oxy hemocyanin, and digestive gland glycogen showed normally distributed data. All the remaining blood parameters were right- or left-skewed. A median live weight of 9.5 g was registered for the sampled population. Median values of 955 and −91.85 mOsm/kg (OP and OC, respectively) were obtained, indicating that shrimp were slightly hypo-osmotic in relation to sea water. A proportion of 27% of OxyHc of the total protein (OxyHc/Prot) was calculated for the F. duorarum population. ProPO and PO showed no normal distribution and were not different between sexes. A right-skewed distribution was observed. Total hemocytes, hyaline (HC) and granular cells (GC) showed differences between sexes, with higher values in females than males. A similar proportion of HC (69%) and GC (30%) of total cells were observed between sexes. Basal and activated respiratory burst showed differences between sexes with higher values for females than for males. The current results provide indicators of the nutritional and immune status of F. duorarum that can be used to detect changes in trophic relations and health at a population level.  相似文献   
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A greater understanding of gendered roles in fisheries is necessary to value the often-hidden roles that women play in fisheries and households. We examine women’s contributions to household food and income using focus group discussions, market surveys, and landings data in six communities in Timor-Leste. Women were actively fishing more days per month than men. Gleaning was the most frequent activity and 100% of trips returned with catch for food and/or income. Mollusc and crab catches were common and exploitation appeared targeted on a dynamic reappraisal of changing food values and changing estimates of group needs. With as many as 80% of households in coastal areas involved in fishing, and at least 50% of women fishing, this highlights the current lack of women’s engagement as a critical gap in fisheries management approaches. The current androcentric dialogue limits social-ecological understanding of these systems and the potential for their effective stewardship.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01335-7) contains supplementary material, which is available to authorized users.  相似文献   
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