Plants influence the atmosphere through fluxes of carbon, water and energy, and can intensify drought through land–atmosphere feedback effects. The diversity of plant functional traits in forests, ...especially physiological traits related to water (hydraulic) transport, may have a critical role in land–atmosphere feedback, particularly during drought. Here we combine 352 site-years of eddy covariance measurements from 40 forest sites, remote-sensing observations of plant water content and plant functional-trait data to test whether the diversity in plant traits affects the response of the ecosystem to drought. We find evidence that higher hydraulic diversity buffers variation in ecosystem flux during dry periods across temperate and boreal forests. Hydraulic traits were the predominant significant predictors of cross-site patterns in drought response. By contrast, standard leaf and wood traits, such as specific leaf area and wood density, had little explanatory power. Our results demonstrate that diversity in the hydraulic traits of trees mediates ecosystem resilience to drought and is likely to have an important role in future ecosystem–atmosphere feedback effects in a changing climate.
The MetaCyc database (MetaCyc.org) is a freely accessible comprehensive database describing metabolic pathways and enzymes from all domains of life. The majority of MetaCyc pathways are ...small-molecule metabolic pathways that have been experimentally determined. MetaCyc contains more than 2400 pathways derived from >46,000 publications, and is the largest curated collection of metabolic pathways. BioCyc (BioCyc.org) is a collection of 5700 organism-specific Pathway/Genome Databases (PGDBs), each containing the full genome and predicted metabolic network of one organism, including metabolites, enzymes, reactions, metabolic pathways, predicted operons, transport systems, and pathway-hole fillers. The BioCyc website offers a variety of tools for querying and analyzing PGDBs, including Omics Viewers and tools for comparative analysis. This article provides an update of new developments in MetaCyc and BioCyc during the last two years, including addition of Gibbs free energy values for compounds and reactions; redesign of the primary gene/protein page; addition of a tool for creating diagrams containing multiple linked pathways; several new search capabilities, including searching for genes based on sequence patterns, searching for databases based on an organism's phenotypes, and a cross-organism search; and a metabolite identifier translation service.
The MetaCyc database (MetaCyc.org) is a comprehensive and freely accessible database describing metabolic pathways and enzymes from all domains of life. MetaCyc pathways are experimentally ...determined, mostly small-molecule metabolic pathways and are curated from the primary scientific literature. MetaCyc contains >2100 pathways derived from >37,000 publications, and is the largest curated collection of metabolic pathways currently available. BioCyc (BioCyc.org) is a collection of >3000 organism-specific Pathway/Genome Databases (PGDBs), each containing the full genome and predicted metabolic network of one organism, including metabolites, enzymes, reactions, metabolic pathways, predicted operons, transport systems and pathway-hole fillers. Additions to BioCyc over the past 2 years include YeastCyc, a PGDB for Saccharomyces cerevisiae, and 891 new genomes from the Human Microbiome Project. The BioCyc Web site offers a variety of tools for querying and analysis of PGDBs, including Omics Viewers and tools for comparative analysis. New developments include atom mappings in reactions, a new representation of glycan degradation pathways, improved compound structure display, better coverage of enzyme kinetic data, enhancements of the Web Groups functionality, improvements to the Omics viewers, a new representation of the Enzyme Commission system and, for the desktop version of the software, the ability to save display states.
•Knowledge of agrobiodiversity impacts on ecosystem services is limited to a few taxa and services.•Functional traits can produce more predictive knowledge of agrobiodiversity impacts on ecosystem ...services.•This approach should be applied across levels of complexity present in agriculture, such as trophic and spatial scales.•Functional traits can be used to create agricultural management strategies that increase ecosystem services.
Functional trait research has led to greater understanding of the impacts of biodiversity in ecosystems. Yet, functional trait approaches have not been widely applied to agroecosystems and understanding of the importance of agrobiodiversity remains limited to a few ecosystem processes and services. To improve this understanding, we argue here for a functional trait approach to agroecology that adopts recent advances in trait research for multitrophic and spatially heterogeneous ecosystems. We suggest that trait values should be measured across environmental conditions and agricultural management regimes to predict how ecosystem services vary with farm practices and environment. This knowledge should be used to develop management strategies that can be easily implemented by farmers to manage agriculture to provide multiple ecosystem services.
Efforts to maximise crop yields are fuelling agricultural intensification, exacerbating the biodiversity crisis. Low‐intensity agricultural practices, however, may not sacrifice yields if they ...support biodiversity‐driven ecosystem services. We quantified the value native predators provide to farmers by consuming coffee's most damaging insect pest, the coffee berry borer beetle (Hypothenemus hampei). Our experiments in Costa Rica showed birds reduced infestation by ~ 50%, bats played a marginal role, and farmland forest cover increased pest removal. We identified borer‐consuming bird species by assaying faeces for borer DNA and found higher borer‐predator abundances on more forested plantations. Our coarse estimate is that forest patches doubled pest control over 230 km² by providing habitat for ~ 55 000 borer‐consuming birds. These pest‐control services prevented US$75–US$310 ha‐year⁻¹ in damage, a benefit per plantation on par with the average annual income of a Costa Rican citizen. Retaining forest and accounting for pest control demonstrates a win–win for biodiversity and coffee farmers.
Diversifying agricultural landscapes may mitigate biodiversity declines and improve pest management. Yet landscapes are rarely managed to suppress pests, in part because researchers seldom measure ...key variables related to pest outbreaks and insecticides that drive management decisions. We used a 13‐year government database to analyse landscape effects on European grapevine moth (Lobesia botrana) outbreaks and insecticides across c. 400 Spanish vineyards. At harvest, we found pest outbreaks increased four‐fold in simplified, vineyard‐dominated landscapes compared to complex landscapes in which vineyards are surrounded by semi‐natural habitats. Similarly, insecticide applications doubled in vineyard‐dominated landscapes but declined in vineyards surrounded by shrubland. Importantly, pest population stochasticity would have masked these large effects if numbers of study sites and years were reduced to typical levels in landscape pest‐control studies. Our results suggest increasing landscape complexity may mitigate pest populations and insecticide applications. Habitat conservation represents an economically and environmentally sound approach for achieving sustainable grape production.
Diversifying agricultural landscapes may mitigate biodiversity declines and improve pest management. We used a 13‐year government database to analyse landscape effects on European grapevine moth (Lobesia botrana) outbreaks and insecticides across c. 400 Spanish vineyards. Our results suggest increasing landscape complexity may mitigate pest outbreaks and insecticide applications.
Addressing the ongoing biodiversity crisis requires identifying the winners and losers of global change. Species are often categorized based on how they respond to habitat loss; for example, species ...restricted to natural environments, those that most often occur in anthropogenic habitats, and generalists that do well in both. However, species might switch habitat affiliations across time and space: an organism may venture into human-modified areas in benign regions but retreat into thermally buffered forested habitats in areas with high temperatures. Here, we apply community occupancy models to a large-scale camera trapping dataset with 29 mammal species distributed over 2,485 sites across the continental United States, to ask three questions. First, are species' responses to forest and anthropogenic habitats consistent across continental scales? Second, do macroclimatic conditions explain spatial variation in species responses to land use? Third, can species traits elucidate which taxa are most likely to show climate-dependent habitat associations? We found that all species exhibited significant spatial variation in how they respond to land-use, tending to avoid anthropogenic areas and increasingly use forests in hotter regions. In the hottest regions, species occupancy was 50% higher in forested compared to open habitats, whereas in the coldest regions, the trend reversed. Larger species with larger ranges, herbivores, and primary predators were more likely to change their habitat affiliations than top predators, which consistently affiliated with high forest cover. Our findings suggest that climatic conditions influence species' space-use and that maintaining forest cover can help protect mammals from warming climates.
Behavioral changes are often animals’ first responses to environmental change and may act as a bellwether for population viability. Nonetheless, most studies of habitat conversion focus on changes in ...species occurrences or abundances. We analyzed >14,000 behavioral observations across 55 bird species in communities in northwestern Costa Rica to determine how land use affects reproductive, foraging, and other passive kinds of behaviors not associated with either foraging or reproduction. Specifically, we quantified differences in behaviors between farms, privately owned forests, and protected areas and implemented a novel modeling framework to account for variation in detection among behaviors. This framework entailed estimating abundances of birds performing different behaviors while allowing detection probabilities of individuals to vary by behavior. Birds were 1.2 times more likely to exhibit reproductive behaviors in forest than in agriculture and 1.5 times more likely to exhibit reproductive behaviors in protected areas than in private forests. Species were not always most abundant in the habitats where they were most likely to exhibit foraging or reproductive behaviors. Finally, species of higher conservation concern were less abundant in agriculture than in forest. Together, our results highlight the importance of behavioral analyses for elucidating the conservation value of different land uses.
Efectos de la agricultura y las reservas naturales sobre el comportamiento de las aves en el noroeste de Costa Rica
Resumen
Los cambios conductuales suelen ser la primera respuesta de los animales ante el cambio ambiental y pueden funcionar como un barómetro para la viabilidad poblacional. Sin embargo, la mayoría de los estudios sobre la conversión del hábitat se enfocan en cambios en la presencia o abundancia de las especies. Analizamos más de 14,000 observaciones conductuales en las comunidades de 55 especies de aves del noroeste de Costa Rica para determinar cómo el uso de suelo afectó el comportamiento reproductivo, de forrajeo y otras formas pasivas no asociadas con las dos anteriores. En específico, cuantificamos las diferencias en el comportamiento entre granjas, bosques de propiedad privada y áreas protegidas e implementamos un marco novedoso de modelado para justificar la variación en la detección entre los comportamientos. Este marco implicó estimar la abundancia de aves que realizaban diferentes comportamientos mientras permitía que variaran las probabilidades de detección de individuos según el comportamiento. Fue 1.2 veces más probable que las aves exhibieran comportamiento reproductivo en el bosque que en las zonas agrícolas y 1.5 veces más probable que exhibieran estos comportamientos en las áreas protegidas que en los bosques privados. Las especies no siempre fueron las más abundantes en los hábitats en donde era más probable que exhibieran comportamientos reproductivos o de forrajeo. Por último, las especies de mayor preocupación para la conservación fueron menos abundantes en las zonas agrícolas que en los bosques. En conjunto, nuestros resultados resaltan la importancia del análisis conductual para ilustrar el valor de conservación de los diferentes usos de suelo.
【摘要】
行为变化通常是动物对环境变化的第一反应, 可用于指示种群生存能力的变化。然而, 大多数关于栖息地转换的研究都侧重于物种的分布或丰度变化。本研究分析了哥斯达黎加西北部地区群落中55种鸟类超过14,000次的行为观察数据, 以确定土地利用类型对繁殖、觅食和除此之外其他被动行为的影响。具体来说, 我们量化分析了鸟类在农场、私有森林和保护地之间的行为差异, 并构建了一个新的模型框架来解释监测到的行为差异。该框架需要估计鸟类不同行为出现的丰度, 同时允许个体的监测概率因行为而异。结果显示, 鸟类在森林中表现出繁殖行为的几率是在农业区的1.2倍, 在保护地表现出繁殖行为的几率是在私有森林的1.5倍。而鸟类最有可能觅食或繁殖的栖息地, 物种丰度并不是最高的。最后, 农业区相比于森林, 出现的受保护程度较高的物种数量较少。总之, 我们的研究结果凸显了行为分析在阐明不同土地利用类型的保护价值方面的重要性。【翻译: 胡怡思; 审校: 聂永刚】
Variability in population densities is key to the ecology of natural systems but also has great implications for agriculture. Farmers' decisions are heavily influenced by their risk aversion to pest ...outbreaks that result in major yield losses. However, the need for long‐term pest population data across many farms has prevented researchers from exploring the drivers and implications of pest population variability (PV). Here, we demonstrate the critical importance of PV for sustainable farming by analyzing 13 years of pest densities across >1300 Spanish olive groves and vineyards. Variable populations were more likely to cause major yield losses, but also occasionally created temporal windows when densities fell below insecticide spray thresholds. Importantly, environmental factors regulating pest variability were very distinct from factors regulating mean density, suggesting variability needs to be uniquely managed. Finally, we found diversifying landscapes may be a win–win situation for conservation and farmers, as diversified landscapes promote less abundant and less variable pest populations. Therefore, we encourage agricultural stakeholders to increase the complexity of the landscapes surrounding their farms through conserving/restoring natural habitat and/or diversifying crops.
The loss of apex predators is known to have reverberating consequences for ecosystems, but how changes in broader predator assemblages affect vital ecosystem functions and services is largely ...unknown. Predators and their prey form complex interaction networks, in which predators consume not only herbivores but also other predators. Resolving these interactions will be essential for predicting changes in many important ecosystem functions, such as the control of damaging crop pests. Here, we examine how birds, bats, and arthropods interact to determine herbivorous arthropod abundance and leaf damage in Costa Rican coffee plantations. In an exclosure experiment, we found that birds and bats reduced non-flying arthropod abundance by ∼35% and ∼25%, respectively. In contrast, birds and bats increased the abundance of flying arthropods, probably by consuming spiders. The frequency of this intraguild predation differed between birds and bats, with cascading consequences for coffee shrubs. Excluding birds caused a greater increase in herbivorous arthropod abundance than excluding bats, leading to increased coffee leaf damage. Excluding bats caused an increase in spiders and other predatory arthropods, increasing the ratio of predators to herbivores in the arthropod community. Bats, therefore, did not provide benefits to coffee plants. Leaf damage on coffee was low, and probably did not affect coffee yields. Bird-mediated control of herbivores, however, may aid coffee shrubs in the long term by preventing pest outbreaks. Regardless, our results demonstrate how complex, cascading interactions between predators and herbivores may impact plants and people.
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