Seeds of many plant species are secondarily dispersed by dung beetles,but the outcome of this interaction is highly *** is known about how certain anthropogenic disturbances affect this plant-animal *** aims of this s...
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Seeds of many plant species are secondarily dispersed by dung beetles,but the outcome of this interaction is highly *** is known about how certain anthropogenic disturbances affect this plant-animal *** aims of this study were to assess the effect of dung type on secondary dispersal by dung beetles in a forest fragment,and to determine whether this interaction is affected by edge *** pitfall traps,we captured dung beetles attracted to dung of 2 frugivorous mammals:woolly monkeys and howler *** found differences between both dung beetle assemblages,but these differences were not consistent in *** seeds surrounded by both dung types,we carried out a field experiment using seeds of 2 plant *** found that the probability of secondary dispersal by dung beetles was higher for seeds placed in woolly monkey ***,we carried out a field experiment using plastic beads as seed mimics to assess edge *** found that secondary seed dispersal by dung beetles was negatively affected by *** disruption of plant-animal interactions along anthropogenic forest edges could have long-term negative effects on forest dynamics by affecting processes of regeneration.
Aims Environmental gradients are drivers of species diversity;however,we know relatively little about the evolutionary processes underlying these relationships.A potentially powerful approach to studying diversity gra...
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Aims Environmental gradients are drivers of species diversity;however,we know relatively little about the evolutionary processes underlying these relationships.A potentially powerful approach to studying diversity gradients is to quantify the phylogenetic structure within and between assemblages arrayed along broad spatial and environmental ***,we evaluate the phylogenetic structure of plant assemblages along an environmental gradient with the expectation that the habitat specialization of entire lineages is an important evolutionary pattern influencing the structure of tree communities along environmental *** We evaluated the effect of several environmental variables on the phylogenetic structure of plant assemblages in 145 plots distributed in northwestern South America that cover a broad environmental *** phylogenetic alpha diversity was quantified for each plot and the phylogenetic beta diversity between each pair of plots was also *** the alpha and beta diversity measures were then related to spatial and environmental gradients in the study *** Findings We found that gradients in temperature and potential evapotranspiration have a strong relationship with the phylogenetic alpha diversity in our study system,with phylogenetic overdispersion in low temperatures and phylogenetic clustering at higher ***,the phylogenetic beta diversity between two plots increases with an increasing difference in temperature,whereas annual precipitation was not a significant predictor of community phylogenetic *** also found that the phylogenetic structure of the plots in our study system was related to the degree of seasonal flooding and seasonality in *** particular,more stressful environments such as dry forests and flooded forests showed phylogenetic ***,in contrast with previous studies,we find that phylogenetic beta diversity was not strongly related to the spatial d
Freshwater biota are more comprehensive and direct indicators of biological impacts,and more meaningful to the public than water quality or physical habitat *** biotic data and the multiple biological indicators devel...
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Freshwater biota are more comprehensive and direct indicators of biological impacts,and more meaningful to the public than water quality or physical habitat *** biotic data and the multiple biological indicators developed from them offer a much richer array of data for assessing the impacts of pollution controls than a limited set of physical or chemical *** recent decades,assemblage-based assessments by ecologists,environmental scientists,and water quality agencies have been employed globally for determining the condition of,and threats to,freshwater ecosystems.A key step in this advance has been the development of multimetric indices(MMIs)or indices of biotic integrity(IBIs)based on quantitative assessments of algae,macrophyte,macroinvertebrate,fish or riparian bird *** Europe,where biological assemblages are mandated for assessing freshwater ecosystem health,many indices are ***,the proliferation of MMIs globally has not always occurred through the application of rigorous study designs and monitoring protocols,nor have they always effectively incorporated functional metrics,stressor assessments,and statistical ***,in this review,we discuss eleven major concerns with the development and application(including logistical limitations)of multimetric indicators based on freshwater biota to encourage more rigorous and widely applicable(transferable)MMI use and ***,our concerns focus on reference conditions;sampling effort,methods,and season;trophic guild definition;metric comprehensiveness,options,screening and scoring;and MMI *** could also benefit from increased attention to ecological mechanisms and metric development,to further improve our understanding of anthropogenic impacts as well as rehabilitation effects on freshwater ecosystems *** closer attention to study designs,ecological mechanisms and metric development should further improve our understa
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