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Rapid growth of the world's human population has increased pressure on landscapes to deliver high levels of multiple ecosystem services, including food and fibre production, carbon storage, biodiversity conservation, and recreation. However, we currently lack general principles describing how to achieve this landscape multifunctionality.We combine theoretical simulations and empirical data on 14 ecosystem services measured across 150 grasslands in three German regions. In doing so, we investigate the circumstances under which spatial heterogeneity in a driver of ecosystem functioning (an "ecosystem‐driver," e.g., the presence of keystone species, land‐use intensification, or habitat types) increases landscape‐level ecosystem multifunctionality.Simulations based on theoretical data demonstrated that relationships between heterogeneity and landscape multifunctionality are highly variable and can range from nonsignificant to strongly positive. Despite this variability, we could identify criteria under which heterogeneity‐landscape multifunctionality relationships were most strongly positive: this happened when multiple ecosystem services responded contrastingly (both positively and negatively) to an ecosystem‐driver.These findings were confirmed using empirical data, which showed that heterogeneity in land‐use intensity (LUI) promoted landscape multifunctionality in cases where functions with both positive (e.g., plant biomass) and negative (e.g., flower cover) responses to land use intensification were included. For example, the simultaneous provisioning of ecosystem functions related to forage production (generally profiting from land‐use intensification), biodiversity conservation and recreation (generally decreasing with land‐use intensification) was highest in landscapes consisting of sites varying in LUI.Synthesis and applications. Our findings show that there are general principles governing landscape multifunctionality. A knowledge of these principles may support land management decisions. For example, knowledge of relationships between ecosystem services and their drivers, such as land use type, can help estimate the consequences of increasing or decreasing heterogeneity for landscape‐level ecosystem service supply, although interactions between landscape units (e.g., the movement of pollinators) must also be considered. Our findings show that there are general principles governing landscape multifunctionality. A knowledge of these principles may support land management decisions. For example, knowledge of relationships between ecosystem services and their drivers, such as land use type, can help estimate the consequences of increasing or decreasing heterogeneity for landscape‐level ecosystem service supply, although interactions between landscape units (e.g., the movement of pollinators) must also be considered. [ABSTRACT FROM AUTHOR]

Summary: The Chocó-Tumbesian region of western Ecuador is one of the 25 global biodiversity hotspots harbouring high numbers of endemic species, which are heavily threatened by habitat loss and fragmentation. Moreover, ongoing climate change in the tropics drives species uphill as lower-lying areas are becoming constantly drier. Such upslope movement can pose major challenges for less mobile species, such as understorey birds which are confined to mature forests and unable to cross habitat gaps. Consequently, these species are threatened by a combination of upslope range shifts and forest fragmentation. In our study, we investigated population numbers and habitat requirements of the Ecuadorian Tapaculo Scytalopus robbinsi, which is endemic to the premontane cloud forests of south-western Ecuador. Comparing the microhabitat structure within territories with control sites revealed that Ecuadorian Tapaculos prefer old secondary forests. Moreover, connectivity between forest fragments was the strongest predictor of the presence of territories within them. We estimated the mean upslope shift of the distribution range as 100 m per decade and developed a model of habitat availability for the revised range. Extrapolating the number of territories from the study area to the distributional range of the Ecuadorian Tapaculo showed that the global population size is smaller than previously assumed. Our results suggest that the Ecuadorian Tapaculo is strongly affected by forest loss and degradation. Therefore, to prevent a continuing decline in population numbers or even extinction, conservation measures focusing on restoring connectivity between fragments and increasing habitat quality and quantity for the remaining populations need to be prioritised. [ABSTRACT FROM AUTHOR]

The traits of animals and plants influence their interaction networks, but the significance of species' traits for the resulting ecosystem functions is poorly understood. A crucial ecosystem function in the tropics is seed dispersal by animals. While the importance of species' traits for structuring plant-frugivore networks is supported by a number of studies, no study has so far identified the functional traits determining the subsequent processes of fruit removal and seedling recruitment. Here, we conducted a comprehensive field study on fruit removal by frugivorous birds and seedling recruitment along an elevational gradient in the Colombian Andes. We measured morphological traits of birds (body mass, bill width, Kipp's index) and plants (plant height, crop mass, fruit width and seed mass) which we expected to be related to fruit removal and seedling recruitment. We tested 1) which bird and plant traits influence fruit removal, and 2) whether network metrics at plant species level, functional identities of frugivores (community-based mean trait values) and/or plant traits were the main determinants of seedling recruitment. We found that large-bodied bird species contributed more to fruit removal than small-bodied bird species and that small-sized fruits were more frequently removed than large-sized fruits. Small plant species and plants with heavy seeds recruited more seedlings than did large plants and plants with light seeds. Network metrics and functional identities of seed dispersers were unrelated to seedling recruitment. Our findings have two important implications. First, large birds are functionally more important than small birds in tropical seed-removal networks. Second, the detected tradeoff between fruit size and seed mass in subsequent recruitment processes suggests that the adaptability of forest plant communities to a loss of large frugivores is limited by life-history constraints. Hence, the protection of large-bodied frugivores is of primary importance for the maintenance of diverse tropical plant communities. [ABSTRACT FROM AUTHOR]

Aims Nectar is one of the most common floral rewards offered to pollinators by plants. Depending on the plant species, nectar is offered openly or in tubes of various lengths restricting accessibility of this resource for flower visitors with short mouthparts. If attracting pollinators that match floral morphology increases pollination efficiency, flowers could profit from signaling nectar-tube depth to pollinators. Since flower colors are important signals in plant-pollinator communication, we investigated whether and which different chromatic or achromatic aspects of flower color might indicate nectar-tube depth or whether flower colors facilitate the differentiation between flowers with long nectar tubes by means of high chromatic uniqueness. Methods To this end, we collected flower reflectance spectra of 135 grassland plant species. We analyzed flower colors as raw reflectance spectra in principal component analysis (PCA) and in the color space of honeybees. Important Findings The correlation between flower colors and tube depths was weak. From the bee's point of view, blue flowers had on average deeper tubes than green, blue-green and UV-green flowers potentially allowing insects to predict tube depths based on blue color. Spectral purity did not correlate with nectar-tube depth, nor did the chromatic uniqueness of flower colors in the honeybee color space. Dominant wavelength showed a significant but very weak correlation with tube depth. The achromatic green contrast decreased with increasing tube depth as did brightness; thus deep tubes were less conspicuous than shallow tubes. Chromatic components resulting from PCA did not or only slightly correlate with tube depth. Our results illustrate that flower colors may have a certain potential to indicate tube depth, i.e. nectar accessibility, from a bee's perspective. [ABSTRACT FROM AUTHOR]