共查询到20条相似文献，搜索用时 0 毫秒
1.
Katherine D. Chau Farida Samad-zada Evan P. Kelemen Sandra M. Rehan 《Global Change Biology》2023,29(15):4193-4211
As urbanization continues to increase, it is expected that two-thirds of the human population will reside in cities by 2050. Urbanization fragments and degrades natural landscapes, threatening wildlife including economically important species such as bees. In this study, we employ whole genome sequencing to characterize the population genetics, metagenome and microbiome, and environmental stressors of a common wild bee, Ceratina calcarata. Population genomic analyses revealed the presence of low genetic diversity and elevated levels of inbreeding. Through analyses of isolation by distance, resistance, and environment across urban landscapes, we found that green spaces including shrubs and scrub were the most optimal pathways for bee dispersal, and conservation efforts should focus on preserving these land traits to maintain high connectivity across sites for wild bees. Metagenomic analyses revealed landscape sites exhibiting urban heat island effects, such as high temperatures and development but low precipitation and green space, had the highest taxa alpha diversity across all domains even when isolating for potential pathogens. Notably, the integration of population and metagenomic data showed that reduced connectivity in urban areas is not only correlated with lower relatedness among individuals but is also associated with increased pathogen diversity, exposing vulnerable urban bees to more pathogens. Overall, our combined population and metagenomic approach found significant environmental variation in bee microbiomes and nutritional resources even in the absence of genetic differentiation, as well as enabled the potential early detection of stressors to bee health. 相似文献
2.
Gerard Martínez-De León;Arianne Marty;Martin Holmstrup;Madhav P. Thakur; 《Oikos》2024,2024(1):e10023
Extreme heat events lower the fitness of organisms by inducing physiological stress and increasing metabolic costs. Yet, little is known about the role of life-history traits in elucidating population responses to extreme heat events. Here, we used a trait-based approach to understand population resistance and recovery using four closely related species of soil-dwelling Collembola. We measured thermal reaction norms of life-history traits (survival and reproductive traits) and used this information to identify ecological mechanisms linked to population responses after an extreme heat event (i.e. one week at 26–30°C, representing + 10°C above ambient conditions). Furthermore, we investigated potential shifts in the body size distribution of recovering populations to better understand if extreme heat events can restructure body size spectra within populations. While resistance remained unaltered across species in our study, the recovery response of the most heat-sensitive species (Protaphorura pseudovanderdrifti, predominantly a boreal species) was strongly affected by the extreme heat event (−54% population change compared to ambient conditions). Given that the fecundity (linked to recovery) of P. pseudovanderdrifti was more sensitive to heat than their survival (linked to resistance), we detected a decoupling between population resistance and recovery to an extreme heat event in this species. In addition, the detrimental effects of heat on fecundity were largely responsible for a drop in the proportion of small-sized (juvenile) individuals in the recovering populations of P. pseudovanderdrifti. Thermally insensitive resistance and recovery in the other three species (P. armata, P. fimata, P. tricampata; predominantly temperate species) can be explained by their high survival and fecundity at warmer temperatures. We highlight that life-history trait responses to warming can help explain population resistance and recovery after extreme heat events. 相似文献
3.
Maxence Gérard Maryse Vanderplanck Markus Franzen Michael Kuhlmann Simon G. Potts Pierre Rasmont Oliver Schweiger Denis Michez 《Oikos》2018,127(8):1095-1103
Body size latitudinal clines have been widley explained by the Bergmann's rule in homeothermic vertebrates. However, there is no general consensus in poikilotherms organisms in particular in insects that represent the large majority of wildlife. Among them, bees are a highly diverse pollinators group with high economic and ecological value. Nevertheless, no comprehensive studies of species assemblages at a phylogenetically larger scale have been carried out even if they could identify the traits and the ecological conditions that generate different patterns of latitudinal size variation. We aimed to test Bergmann's rule for wild bees by assessing relationships between body size and latitude at continental and community levels. We tested our hypotheses for bees showing different life history traits (i.e. sociality and nesting behaviour). We used 142 008 distribution records of 615 bee species at 50 × 50 km (CGRS) grids across the West Palearctic. We then applied generalized least squares fitted linear model (GLS) to assess the relationship between latitude and mean body size of bees, taking into account spatial autocorrelation. For all bee species grouped, mean body size increased with higher latitudes, and so followed Bergmann's rule. However, considering bee genera separately, four genera were consistent with Bergmann's rule, while three showed a converse trend, and three showed no significant cline. All life history traits used here (i.e. solitary, social and parasitic behaviour; ground and stem nesting behaviour) displayed a Bergmann's cline. In general there is a main trend for larger bees in colder habitats, which is likely to be related to their thermoregulatory abilities and partial endothermy, even if a ‘season length effect’ (i.e. shorter foraging season) is a potential driver of the converse Bergmann's cline particularly in bumblebees. 相似文献
4.
Within-species variation in animal body size predicts major differences in life history, for example, in reproductive development, fecundity, and even longevity. Purely from an energetic perspective, large size could entail larger energy reserves, fuelling different life functions, such as reproduction and survival (the “energy reserve” hypothesis). Conversely, larger body size could demand more energy for maintenance, and larger individuals might do worse in reproduction and survival under resource shortage (the “energy demand” hypothesis). Disentangling these alternative hypotheses is difficult because large size often correlates with better resource availability during growth, which could mask direct effects of body size on fitness traits. Here, we used experimental body size manipulation in the freshwater cnidarian Hydra oligactis, coupled with manipulation of resource (food) availability to separate direct effects of body size from resource availability on fitness traits (sexual development time, fecundity, and survival). We found significant interaction between body size and food availability in sexual development time in both males and females, such that large individuals responded less strongly to variation in resource availability. These results are consistent with an energy reserve effect of large size in Hydra. Surprisingly, the response was different in males and females: small and starved females delayed their reproduction, while small and starved males developed reproductive organs faster. In case of fecundity and survival, both size and food availability had significant effects, but we detected no interaction between them. Our observations suggest that in Hydra, small individuals are sensitive to fluctuations in resource availability, but these small individuals are able to adjust their reproductive development to maintain fitness. 相似文献
5.
6.
Markus A. K. Sydenham Lise D. Häusler Stein R. Moe Katrine Eldegard 《Ecology and evolution》2016,6(2):412-425
Inter‐specific interactions are important drivers and maintainers of biodiversity. Compared to trophic and competitive interactions, the role of non‐trophic facilitation among species has received less attention. Cavity‐nesting bees nest in old beetle borings in dead wood, with restricted diameters corresponding to the body size of the bee species. The aim of this study was to test the hypothesis that the functional diversity of cavity‐producing wood boring beetles ‐ in terms of cavity diameters ‐ drives the size diversity of cavity‐nesting bees. The invertebrate communities were sampled in 30 sites, located in forested landscapes along an elevational gradient. We regressed the species richness and abundance of cavity nesting bees against the species richness and abundance of wood boring beetles, non‐wood boring beetles and elevation. The proportion of cavity nesting bees in bee species assemblage was regressed against the species richness and abundance of wood boring beetles. We also tested the relationships between the size diversity of cavity nesting bees and wood boring beetles. The species richness and abundance of cavity nesting bees increased with the species richness and abundance of wood boring beetles. No such relationship was found for non‐wood boring beetles. The abundance of wood boring beetles was also related to an increased proportion of cavity nesting bee individuals. Moreover, the size diversity of cavity‐nesting bees increased with the functional diversity of wood boring beetles. Specifically, the mean and dispersion of bee body sizes increased with the functional dispersion of large wood boring beetles. The positive relationships between cavity producing bees and cavity nesting bees suggest that non‐trophic facilitative interactions between species assemblages play important roles in organizing bee species assemblages. Considering a community‐wide approach may therefore be required if we are to successfully understand and conserve wild bee species assemblages in forested landscapes. 相似文献
7.
Shuqing Zhao Changhui Peng Hong Jiang Dalun Tian Xiangdong Lei Xiaolu Zhou 《Ecological Research》2006,21(6):890-896
Viewed within a historical context, Asia has experienced dramatic land transformations, and currently more than 50% of Asian
land area is under agriculture. The consequences of this transformation are manifold. Southeast Asia has the highest deforestation
rate of any major tropical region. Many of the world’s large rivers and lakes in Asia have been heavily degraded. About 11
of 19 world megacities with more than 10 million inhabitants are in Asia. These land use activities have resulted in substantial
negative ecological consequences, including increased anthropogenic CO2 emissions, deteriorated air and water quality, alteration of regional climate, an increase of disease and a loss of biodiversity.
Although land use occurs at the local level, it has the potential to cause ecological impact across local, regional and global
scales. Reducing the negative environmental impacts of land use change while maintaining economic viability and social acceptability
is an major challenge for most developing countries in Asia. 相似文献
8.
9.
Dan F. B. Flynn Melanie Gogol-Prokurat Theresa Nogeire Nicole Molinari Bárbara Trautman Richers Brenda B. Lin Nicholas Simpson Margaret M. Mayfield Fabrice DeClerck 《Ecology letters》2009,12(1):22-33
Land use intensification can greatly reduce species richness and ecosystem functioning. However, species richness determines ecosystem functioning through the diversity and values of traits of species present. Here, we analyze changes in species richness and functional diversity (FD) at varying agricultural land use intensity levels. We test hypotheses of FD responses to land use intensification in plant, bird, and mammal communities using trait data compiled for 1600+ species. To isolate changes in FD from changes in species richness we compare the FD of communities to the null expectations of FD values. In over one-quarter of the bird and mammal communities impacted by agriculture, declines in FD were steeper than predicted by species number. In plant communities, changes in FD were indistinguishable from changes in species richness. Land use intensification can reduce the functional diversity of animal communities beyond changes in species richness alone, potentially imperiling provisioning of ecosystem services. 相似文献
10.
Peter H. Niewiarowski Arthur E. Dunham 《Evolution; international journal of organic evolution》1998,52(4):1236-1241
Using data and reanalysis of a model published by Shine and Schwarzkopf (1992) we reject the two unsubstantiated assertions made by Shine et al. (1996) about modeling the evolution of reproductive effort in squamate reptiles: (1) mortality schedules do not affect predictions of the Shine and Schwarzkopf (1992) model; and (2) growth rates that would affect the predictions of the original model are biologically unreasonable. On the basis of these two points alone, we strongly reject Shine et al.'s (1996) claim that a critique by Niewiarowski and Dunham (1994) actually reinforces the original conclusions of Shine and Schwarzkopf (1992). Furthermore, results and data presented here are strong enough to severely circumscribe the generality of the Shine and Schwarzkopf (1992) model. Though we do not provide data or new analyses of the potential effects of offspring size variation, we reaffirm the position of Niewiarowski and Dunham (1994) that the sensitivity of the Shine and Schwarzkopf (1992) model to such effects should be explored before using it as a basis for structuring future research on the evolution of reproductive effort in squamate reptiles. 相似文献
11.
R. Shine L. Schwarzkopf M. J. Caley 《Evolution; international journal of organic evolution》1996,50(5):2111-2114
12.
- The interspecific relationships between abundance and site occupancy have been widely studied in plants and animals, but principally in terrestrial systems. With few exceptions, a positive abundance–occupancy relationship has been reported. Few publications have included freshwater fish, possibly suggesting a general lack of abundance–occupancy patterns for this taxonomic group.
- We examined the relationship between abundance and the extent of site occupancy by 145 species of freshwater fish, including nine non‐indigenous species, sampled over 85 sites spread across the Duck River Basin, Tennessee, U.S.A.
- A distinct (r2 = 0.79) positive abundance–occupancy curve was observed, with curves differing relative to feeding and size guilds, but not relative to environmental tolerance, conservation status (i.e. listed/non‐listed), or origin (i.e. indigenous/non‐indigenous).
- The patterns observed are consistent with those reported in many studies of terrestrial taxa.
- The existence of positive abundance–occupancy relationships in stream fish has at least two major implications for fish conservation. First, species that decrease in occupancy due to anthropogenic disturbances are likely to decrease in abundance, facing inflated prospects for local extinction. Second, occupancy alone may be used to index community status and the need for, or success of, conservation activities.
13.
14.
15.
Leon Marshall Floor Perdijk Nicolas Dendoncker William Kunin Stuart Roberts Jacobus C. Biesmeijer 《Proceedings. Biological sciences / The Royal Society》2020,287(1938)
In a warming climate, species are expected to shift their geographical ranges to higher elevations and latitudes, and if interacting species shift at different rates, networks may be disrupted. To quantify the effects of ongoing climate change, repeating historical biodiversity surveys is necessary. In this study, we compare the distribution of a plant–pollinator community between two surveys 115 years apart (1889 and 2005–06), reporting distribution patterns and changes observed for bumblebee species and bumblebee-visited plants in the Gavarnie-Gèdre commune in the Pyrenees, located in southwest Europe at the French–Spanish border. The region has warmed significantly over this period, alongside shifts in agricultural land use and forest. The composition of the bumblebee community shows relative stability, but we observed clear shifts to higher elevations for bumblebees (averaging 129 m) and plants (229 m) and provide preliminary evidence that some bumblebee species shift with the plants they visit. We also observe that some species have been able to occupy the same climate range in both periods by shifting elevation range. The results suggest the need for long-term monitoring to determine the role and impact of the different drivers of global change, especially in montane habitats where the impacts of climate changes are anticipated to be more extreme. 相似文献
16.
Understanding the magnitude and long‐term patterns of selection in natural populations is of importance, for example, when analysing the evolutionary impact of climate change. We estimated univariate and multivariate directional, quadratic and correlational selection on four morphological traits (adult wing, tarsus and tail length, body mass) over a time period of 33 years (≈ 19 000 observations) in a nest‐box breeding population of collared flycatchers (Ficedula albicollis). In general, selection was weak in both males and females over the years regardless of fitness measure (fledged young, recruits and survival) with only few cases with statistically significant selection. When data were analysed in a multivariate context and as time series, a number of patterns emerged; there was a consistent, but weak, selection for longer wings in both sexes, selection was stronger on females when the number of fledged young was used as a fitness measure, there were no indications of sexually antagonistic selection, and we found a negative correlation between selection on tarsus and wing length in both sexes but using different fitness measures. Uni‐ and multivariate selection gradients were correlated only for wing length and mass. Multivariate selection gradient vectors were longer than corresponding vector of univariate gradients and had more constrained direction. Correlational selection had little importance. Overall, the fitness surface was more or less flat with few cases of significant curvature, indicating that the adaptive peak with regard to body size in this species is broader than the phenotypic distribution, which has resulted in weak estimates of selection. 相似文献
17.
Land‐use change may alter both species diversity and species functional diversity patterns. To test the idea that species diversity and functional diversity changes respond in differing ways to land‐use changes, we characterize the form of the change in bird assemblages and species functional traits along an intensifying gradient of land use in the savanna biome in a historically homogeneous vegetation type in Phalaborwa, South Africa. A section of this vegetation type has been untransformed, and the remainder is now mainly characterized by urban and subsistence agricultural areas. Using morphometric, foraging and breeding functional traits of birds, we estimate functional diversity changes. Bird species richness and abundance are generally higher in urban and subsistence agricultural land uses, as well as in the habitat matrix connecting these regions, than in the untransformed area, a pattern mainly driven through species replacement. Functionally unique species, particularly ground nesters of large body size, were, however, less abundant in more utilized land uses. For a previously homogenous vegetation type, declines in the seasonality of energy availability under land‐use change have led to an increase in local avian diversity, promoting the turnover of species, but reduced the abundance of functionally unique species. Although there is no simple relationship between land‐use and diversity change, land‐use change may suit some species, but such change may also involve functional homogenization. 相似文献
18.
Fermín J. Chamorro Christiana M. A. Faria Francisca S. Araújo Breno M. Freitas 《Insect Conservation and Diversity》2023,16(1):16-32
- To sample bee communities, a combination of methods is necessary, the most common being hand netting (HN) and pan traps (PT). However, there has been little exploration into how vertical distribution of PT can improve their sampling efficiency, also taking the temporal variation of floral resources into account.
- Here, we analysed the properties of bee communities sampled with PT at different heights (1.6 and 4.0 m) compared with PTs close to the ground, HN and large blue bucket trap (BB). In addition, we tested the effect of variation in the availability of floral resources on the performance of each method. Bees were collected in fragments of the Brazilian Caatinga.
- We captured 60 bee species with PTs, HN and BB, with significant increases in the sample coverage with elevated bowls (BB = 56.7%, HN = 60.0%, PT0.3 m = 23.3%, PT1.6 m = 36.7%, PT4.0 m = 50.0%). Elevating the bowls increased the sampling of bees with larger body size. Considering the three heights, PTs registered similar richness compared to HN and BB, but differed in the composition of species and ecological traits.
- When floral resource availability was greater, the abundance and richness of bees caught in PTs decreased, however, the elevated PT increased their ecological uniqueness (degree of uniqueness of the samples in terms of community composition). Thus, elevating PTs enables the capture of bees that forage at a specific height when floral resources increase.
- Our results highlight the importance of the vertical distribution of PT for sampling bees, since it improves their performance and its complementarity with other methods.
19.
- One of the main causes of biodiversity loss in aquatic ecosystems is instream habitat change associated with land‐use change in the drainage basin. Biofuel crop production is an increasingly important driver of land‐use change in existing agricultural drainage basins. Conceptually, biofuels such as sugarcane (Saccharum spp.: Poaceea) can provide a sustainable alternative to fossil fuels, but little is known about the consequences of biofuel crop production for biodiversity. Thus, our aim was to investigate if and how the degree of further environmental changes at regional and local scales can influence taxonomic and functional structure of fish assemblages in agroecosystem streams.
- We quantified drainage basin land use, instream and riparian habitat, and fish assemblages in 38 agroecosystem streams in Brazil with drainage basins experiencing rapid expansion of sugarcane production, and calculated degree of environmental change and corresponding response in taxonomic and functional structure of stream fish assemblages. Procrustes and redundancy analyses tested for correlation between land use and instream habitat and environmental factors correlated with fish assemblage structure, respectively. Previous studies demonstrated relationships between land‐use change, instream habitat change and taxonomic and functional structure of stream fish assemblages. Therefore, we used regression to test the hypothesis that degree of environmental change is positively correlated with magnitude of change in taxonomic and functional structure of fish assemblages.
- Primary gradients of environmental change included conversion of pasture to sugarcane and reduction of stream width, depth and volume. Although drainage basin and instream attributes were not correlated within a year, we detected a legacy effect of land use on instream habitat. The degree of environmental change was not significantly correlated with taxonomic or functional changes in stream fish assemblages in most cases. However, abundances of resistant taxa increased, whereas nektonic functional groups decreased, and the biological response also presented evidence of a legacy effect.
- Our findings demonstrate that instream habitat and aquatic biodiversity in streams with agricultural drainage basins undergoing rapid conversion to biofuel production likely will not experience the full magnitude of responses in the short term. Therefore, repeated sampling of sufficient duration to account for legacy effects or time lags is needed to test for effects of biofuel expansion on biodiversity, and similarly to assess whether management practices such as riparian zone preservation can benefit biodiversity in agroecosystems.
20.
A. Juárez‐Escario X.O. Solé‐Senan J. Recasens A. Taberner J.A. Conesa 《The Annals of applied biology》2018,173(1):42-54
Agricultural intensification in Europe during the past 30 years has led to changes in compositional and functional weed structure in agroecosystems as well as increases in the prominence of alien weeds. Irrigation is a major driver of agricultural intensification, particularly in semi‐arid zones of the Mediterranean. In the past few decades, irrigated land has expanded in semi‐arid agricultural lands in northeastern Spain. The goals of this study were to identify long‐term temporal changes in compositional and functional weed communities in annual (i.e. maize crops) and perennial (i.e. orchards) irrigated crops of this area and determine whether these changes differentially affect native and alien plants. Changes in the diversity, composition and functional groups of the weed communities in fruit‐tree orchards and maize crops were assessed using plant surveys in 1989 and 2009. During the studied period, a decrease was recorded in the diversity of native species in the fruit‐tree orchards; this decrease was accompanied by an increase in alien weed diversity and a general homogenisation of species in the weed community. In the maize crops, the diversity values of native and alien plants changed little during 20 years. The identification of functional groups revealed that most of the species whose cover increased in the fruit‐tree orchards were graminoid alien species that perform C4 photosynthesis and disperse seed via water or a combination of vectors. In the maize crops, the identified functional groups did not differ in the proportion of species whose cover changed between 1989 and 2009. Hence, in irrigated orchards the observed changes in the weed community and the prominence of alien species are mediated by the selection of a set of traits that let species to overcome management filters. Similarly, the stability of functional composition of weed communities in maize fields is the result of the selection of species functionally similar to the crop. 相似文献