Basic and Applied Ecology最新文献

In temperate regions, larger mammalian carrion naturally occurs in terrestrial landscapes as a pulsed resource towards the end of the winter through enhanced ungulate mortality due to starvation or exhaustion. The return of large carnivores in Central Europe provides carrion more equally throughout the year and the active enhancement of carrion for biodiversity by game managers has increased, raising the question of how different scavengers respond to the temporal variation in carrion supply. To address this question, we experimentally deployed 106 cervid carcasses throughout the year in a temperate forest of south-eastern Germany on two types of plots: permanent (i.e., site with multiple subsequent deployments) or random (i.e., site with unique deployment), and reported vertebrate scavenger visitations by camera trapping. Deployment on random or permanent sites did not affect carrion use by any single species. Generalized additive modelling revealed that vertebrate scavenging peaked in the winter season and summer independent of carrion supply. Still, different scavenger species showed different temporal patterns. While wild boar as ungulate omnivores did not display any seasonal patterns, avian scavengers showed significant variation in visitation rates. The mesopredator red fox consumed carrion significantly more often from late winter to summer, while pine marten was present at carrion only during winter. Finally, the specialist large carnivore Eurasian lynx, visited carrion sites most frequently in late winter and early spring. Our results suggest that global warming might impact some groups of vertebrate scavengers more strongly than others by reducing carrion availability in late winter, while returning carnivores could mitigate these impacts.

Interaction with urban nature provides many nature-derived benefits for people. However, human-nature interaction studies are conducted primarily during the vegetative season, but remain largely unexplored in winter. We therefore used non-participatory methods (i.e. systematically observing park users on-site) to characterize human-nature interactions in three urban parks in Stuttgart, Germany in the winter of 2020/2021 (N = 13,474 observations). Descriptive statistics were calculated and two multivariate logistic regression models built to serve as the basis for analyses. Results indicated that high-engagement human-nature interaction (i.e. nature photography, active observation, touching, or collecting natural elements) was generally low (2.4 % of observations) and that park visitors most frequently interacted with flora, then fauna, and finally abiotic natural elements. Certain visitation behaviors including technology use and visiting alone were associated with a lower odds of high-engagement nature interaction, whereas walking a dog was associated with a higher odds of high-engagement nature interaction. Additionally, odds of high-engagement nature interaction were higher at sites with a naturalized pond. While these findings are context-specific, they provide insight into the number of people that participate in high-engagement nature interaction, details into how they interact with urban nature in winter, and have potential implications for the design and management of urban greenspaces in future cities that best support both people and nature year round.

Future cities have the potential to be biodiverse areas in which humans and wildlife can coexist. However, the success of creating or maintaining wildlife-inclusive future cities can be challenged by management actions that are solely based on ecological research, while overlooking research on human perspectives. Despite the growth of literature on human-wildlife interactions, which complements the breadth of urban ecology research, the overlap between these two research areas is still uncommon. In this study, we reviewed the literature of wild mammals in urban areas to identify patterns and gaps in the literature. We found 848 published journal articles, of which 480 articles focused on wildlife ecology, 269 articles focused on human dimensions and 99 articles had interdisciplinary combinations of both. Ecology-centered publications tended to be about habitat, rather than behavior, diet, health, reproduction and inter-species-relations, and literature on human dimensions was more evenly divided into management, perception, conflict and coexistence. Most ecology studies reported on specific taxonomic families, mainly canids and murids, but in human-dimension studies, “wildlife” was considered more as a general community of species. The most studied interdisciplinary combination of research themes was wildlife habitat and human-wildlife conflicts (n = 22), while only nine studies incorporated perception with ecological research. Even though studies on human dimensions of wildlife in cities are increasing, interdisciplinary research is lacking, which limits the knowledge on how to manage and shape urban areas to achieve coexistence of humans and wild mammals. For future cities to successfully become biophilic and support human-wildlife coexistence, we outlined five key elements for a research agenda: 1) Investigate urban mammal research through an interdisciplinary lens; 2) Explore ecological dynamics beyond habitat selection; 3) Conduct research for coexistence; 4) Disentangle what is “urban wildlife”; 5) Study a diverse array of urban wild mammals.

Understanding the effects of microhabitat changes on arthropod predator communities and their prey in agroecosystems is essential for field management and biocontrol. Few studies have investigated the trait composition of web-building spider communities in rice ecosystems. Here, we examined how temporal changes during the rice field development affect the abundance and traits of orb-web spiders, and how these effects consequently influence captured prey number and prey composition in irrigated rice ecosystems in southern Thailand. We used structural equation models to evaluate direct and indirect, spider-mediated effects of rice field development on captured prey numbers in each different guild. We found that the number of horizontal web-building spiders decreased during the rice field development, whereas there was no significant change in number of vertical web-building spiders. The number of captured detritivorous insects was positively related to the numbers of horizontal and vertical web-building spiders, while phytophagous insects and others were positively related only to the numbers of vertical web-building spiders. Moreover, the prey number captured by vertical web-building spiders seems to be indirectly increased through the decreasing number of horizontal web-building spiders in the late rice season. A fourth-corner analysis showed that spider species identity, spider traits (web type, web height and web diameter), vegetation height, and water level generally influenced the prey captured by web-building spiders. Horizontal web-building spider species with lower web placement during the flooding phase captured high numbers of detritus-feeding insects, while vertical web-building spider species with higher web placement captured high numbers of rice pests, predators and others. Our results suggest that the field development acted as an environmental factor that determined the species identity and traits of web-building spider communities. The findings of this study can help to predict the ecosystem services provided by the web-building spider community in rice ecosystems.

Agricultural intensification and expansion are regarded as main drivers of biodiversity loss. This conclusion is mainly based on observed declines of local diversity (α-diversity), while effects on community composition homogenization (decrease of β-diversity) at a larger spatial scale are less well understood. Carabid beetles and spiders represent two widespread guilds and are important predators of pest species. Here we surveyed carabid beetles and spiders in 66 winter wheat fields in four northwestern European countries (Germany, the Netherlands, Sweden and UK) and analyzed how their community composition was related to geographic distance (separation distance between any pairwise fields) and three environmental variables: crop yield (proxy for land-use intensity), percentage cropland (proxy for landscape complexity) and soil organic carbon content (proxy for local soil conditions). We further analyzed whether the relationship between carabid beetle and spider community composition and geographic distance was influenced by environmental variables. We found that, 55 % and 75 % of all observed carabid and spider individuals, respectively, belonged to species that occurred in all four countries. However, individuals of species that were unique to a particular country only accounted for 3 % of all collected individuals for both taxa. Furthermore, we found a negative relationship between distance and similarity of spider communities but not for carabid beetle communities. None of the environmental variables were related to similarity of carabid beetle and spider communities, nor moderated the effects of distance. Our study indicates that across a great part of the European continent, arthropod communities (especially carabid beetles) in agricultural landscapes are composed of very similar species that are robust to current variations in environment and land-use.

Nitrogen (N) fixation by moss-cyanobacteria associations has been recognized as an important N input pathway in many ecosystems from arctic tundra to tropical forests. However, the transfer of fixed N₂ from mosses to the soil as well as the effects of rainfall frequency and volume on this N transfer has hardly been studied – even though mosses can leach nutrients upon rewetting. In this study, we investigated the transfer of fixed N₂ by moss-cyanobacteria associations in one month under four watering regimes with a combination of high and low volume and frequency. For this, we used two morphologically similar moss species collected from ecosystems with different climate and N availability (subarctic - Hylocomium splendens; and tropical - Thuidium delicatulum). Acetylene reduction assays were conducted as a measure of N₂ fixation rates in mosses, and ¹⁵N-N₂ tracing was used to follow the fixed N₂ from moss to the underlying substrate. Nitrogen fixation rates were higher in T. delicatulum than in H. splendens, but rainfall volume and frequency did not show strong effects on N₂ fixation rates. Nonetheless, the extent of N leached from mosses was more sensitive to an increase in rainfall volume than to an increase in frequency, and more N was lost from T. delicatulum under high volume precipitation than from H. splendens. Both total nitrogen and ¹⁵N enrichment results demonstrate that the fixed N₂ was mostly stored in moss tissues with less than 1 % leached to the substrate. Our results show that both moss species retain almost all fixed N₂ within their tissues under small rainfall disturbances within one month, while increased N availability under higher precipitation volume renders some moss species an important N source for the soil.

Agricultural intensification decreases the heterogeneity of the landscape and leads to a decline in hedgerows. As hedgerows provide important habitats for many taxa, this contributes to the loss of biodiversity in agroecosystems. However, the extent to which hedgerows, and in particular their habitat quality in terms of structural characteristics, also influence biodiversity-based ecosystem services is poorly studied. Here, we conducted a systematic review of the Scopus and other literature databases focusing on Central European and UK studies examining (1) the influence of hedgerow habitat quality on the biodiversity of arthropods, earthworms, birds, bats and small mammals and (2) the relationship between selected hedgerow parameters, animal taxa, and ecosystem services such as pollination, seed dispersal, pest and disease control and soil quality regulation. A total of 2260 studies (cut-off date: 13 September 2022) published between 1974 and 2022 were found. After sorting based on inclusion criteria related to the research focus, 89 studies remained for evaluation. Arthropods, birds, and small mammals were studied most frequently, earthworms and bats least frequently. The selected studies showed that structural diversity, layering, woody biomass and density were strongly positively correlated with animal species diversity, while hedgerow length, width and age showed less relevant relationships. Hedgerow connectivity, density, structural diversity, and layering were strongly positive associated with the provision of ecosystem services. We conclude that the structural diversity of hedgerows needs to be increased if their impact on biodiversity and ecosystem service provision is to be improved. It is therefore recommended that hedgerow management measures should specifically consider the ecological importance of the structural diversity of hedgerows.

Faced with pollinator declines, cities could serve as refuges for biodiversity conservation by managing floral resources in public green spaces. Ornamental plants could play an important role in attracting pollinators because they form part of urban floral management. However, knowledge of how their floral traits respond to drought is lacking, and it is unknown whether they will be suitable for pollinators under future climates. The main objective of this study was to determine the covariation of floral traits of ornamental plant species and effects of drought on them. To this end, in a city greenhouse we measured floral traits of eight ornamental species commonly used in urban green spaces in France. We subjected the plants to a control treatment or a drought treatment, reducing the volume and frequency of watering. We observed interspecific variability in floral traits among these species and a change in covariation between the traits pollen quantity and nectar quantity in the drought treatment. Drought influenced morphological traits related to floral display more than other floral traits, with mean decreases of 28 % in floral height, 35 % in floral area and 58 % in the number of floral units. Ornamental plants seemed attractive to different morphotypes of pollinators depending on their floral unit number, nectar sugar concentration or nectar tube depth, with most visits made by Hymenoptera. These results are expected to encourage green-space managers to select urban plants according to their functional characteristics and adapt their choice of plants to climate change.

The introduction of carnivores to islands affects the conservation status of native prey. For two decades, American mink (Neogale vison) has expanded its distribution in the sub-Antarctic archipelago of Austral Patagonia, while preying on nests of solitary ground-nesting birds. Here, upland geese (Chloephaga picta) and flightless steamer ducks (Tachyeres pteneres) are naïve to such predation risk because of the lack of native terrestrial predators. We used nest occupancy models to reveal preferred breeding habitats of those two ground-nesting waterbirds to prioritize areas for future mink control programs. We searched for nests along 80 transects on Navarino Island, southernmost Chile, and 11 transects on 10 nearby islets (3 ± 2.9 ha). Our results showed that islets were essential for breeding in comparison to the main island (5.3 nests/km versus 0.8 nests/km, respectively). The occupancy models revealed that islets were particularly important for flightless steamer ducks, endemic to western Patagonia. As breeding habitat, upland geese preferred medium-dense shrubland, and flightless steamer ducks preferred rocky coastlines. Nest detection was negatively affected by dense vegetation and, in the case of the upland geese, towards the end of the survey. Ten camera traps (n = 385 trap nights) revealed mink presence on all islets, highlighting their capacity to swim in cold water, up to 340 m distance from the main island. We conclude that islets represent breeding refuges for ground-nesting waterbirds and therefore advocate allocating resources for mink control during the warm season on islets. We also provide predictive maps of nesting habitat preference of upland geese and flightless steamer ducks for conservation managers to focus their often scarce human and financial resources on areas critical for breeding. Finally, we argue that detection probability should be an integral part of bird breeding studies, which can be methodologically achieved through targeting transects, not nests, as sample units.