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Climate change and increasing human activities are impacting ecosystems and their biodiversity. Quantitative measurements of essential biodiversity variables(EBV) and essential climate variables are used to monitor biodiversity and car-bon dynamics and evaluate policy and management interventions. Ecosystem structure is at the core of EBVs and carbon stock estimation and can help to inform assessments of species and species diversity. Ecosystem structure is also used as an indirect indicator of habitat quality and expected species richness or species community composition. Space borne measurements can provide large-scale insight into monitoring the structural dynamics of ecosystems, but they generally lack consistent, robust, timely and detailed information regarding their full three-dimensional vegetation structure at local scales. Here we demonstrate the potential of high-frequency ground-based laser scanning to systematically monitor structural changes in vegetation. We present a proof of concept high-temporal ecosystem structure time series of 5 years in a temperate forest using terrestrial laser scanning (TLS). We also present data from automated high-temporal laser scanning that can allow up scaling of vegetation structure scanning, overcoming the limitations of a typically opportunistic TLS measurement approach. Automated monitoring will be a critical component to build a network of field monitoring sites that can provide the required calibration data for satellite missions to effectively monitor the structural dynamics of vegetation over large areas. Within this perspective, we reflect on how this network could be designed and discuss implementation pathways.

Aim Animal migrations influence ecosystem structure, dynamics and persistence of predator and prey populations. The theory of migratory coupling postulates that aggregations of migrant prey can induce large-scale synchronized movements in predators, and this coupling is consequential for the dynamics of ecological communities. The degree to which humans influence these interactions remains largely unknown. We tested whether creation of large resource pulses by humans such as seasonal herding of reindeer Rangifer tarandus and hunting of moose, Alces alces, can induce migratory coupling with Golden Eagles, Aquila chrysaetos, and whether these lead to demographic consequences for the eagles. Location Fennoscandia. Methods We used movement data from 32 tracked Golden Eagles spanning 125 annual migratory cycles over 8 years. We obtained reindeer distribution data through collaboration with reindeer herders based on satellite tracking of reindeer, and moose harvest data from the national hunting statistics for Sweden. We assessed demographic consequences for eagles from ingesting lead from ammunition fragments in moose carcasses through survival estimates and their links with lead concentrations in eagles' blood. Results In spring, eagles migrated hundreds of kilometres to be spatially and temporally coupled with calving reindeer, whereas in autumn, eagles matched their distribution with the location and timing of moose hunt. Juveniles were more likely to couple with reindeer calving, whereas adults were particularly drawn to areas of higher moose harvest. Due to this coupling, eagles ingested lead from spent ammunition in moose offal and carcasses and the resulting lead toxicity increased the risk of mortality by 3.4 times. Main conclusions We show how migratory coupling connects landscape processes and that human actions can influence migratory coupling over large spatial scales and increase demographic risks for predators. We provide vital knowledge towards resolving human-wildlife conflicts and the conservation of protected species over a large spatial and temporal scale.

Freshwater ecosystems have been degraded by multiple stressors. To mitigate the effects of multiple stressors on freshwater ecosystems, we must assess the current ecological condition of these systems, diagnose the cause of the environmental impact, and predict how they will respond to future changes in anthropogenic pressures. Most biomonitoring programs use metrics of community structure to quantify ecological condition; however, they do not assess the overall ecological integrity of an ecosystem, including ecosystem function. This series of papers explores how structural and functional aspects of stream ecosystems can respond to different stressors. The use of a combination of structural and functional measures increases the ability to assess degradation of stream ecosystem integrity. We suggest that future studies should focus on development of measures that integrate ecosystem structure and function, such as the identification and refinement of species traits that are clearly associated with important functional properties of species and whose responses to different anthropogenic pressures can aid in informing the specific management activities likely to be most effective in restoring degraded stream ecosystems.

Avian communities are very good indicators of integrity and stability of ecosystem structure and functions. Assessment of bird assemblages in different landscapes is therefore emphasized from an environmental monitoring viewpoint. Bird surveys were carried out from April 2015 to March 2016 to document the avian species assemblage of agricultural landscapes in Panipat, Haryana, India. Point-transect in amalgam with opportunistic encounter methods were used to collect data. A total of 101 bird species under 44 families and 15 orders were recorded from the study area. The bird species richness was highest for the order Passeriformes (48), followed by Pelecaniformes (15), Charadriiformes (6), and the remaining 12 orders. Ardeidae was the most diverse bird family in the study area. Among the recorded avifauna, 77 species were residents, 18 species were winter migrants and six species were summer migrants. Species richness was recorded to be highest in the month of January compared to the remaining months. Species richness, abundance, diversity and evenness differed significantly (P < 0.05) between seasons as well as among the agricultural landscapes. Most bird species were insectivorous (36) followed by carnivorous (26), omnivorous (24), granivorous (9), frugivorous (5) and nectarivorous (1). Painted Stork Mycteria leucocephala, Black-necked Stork Ephippiorhynchus asiaticus, Black-headed Ibis Threskiornis melanocephalus, and Alexandrine Parakeet Psittacula eupatria are four Near Threatened species found in this region. Interestingly, five species having globally declining population trends are still common in the study area. The observed richness of avian species in the study area calls for further studies on habitat preference, seasonal changes, nest ecology, and breeding biology to understand species specific roles of birds in agro-ecosystems.

Large carnivores can exert top–down effects in ecosystems, but the size of these effects are largely unknown. Empirical investigation on the importance of large carnivores for ecosystem structure and functioning presents a number of challenges due to the large spatio-temporal scale and the complexity of such dynamics. Here, we applied a mechanistic global ecosystem model to investigate the influence of large-carnivore removal from undisturbed ecosystems. First, we simulated large-carnivore removal on the global scale to inspect the geographic pattern of top–down control and to disentangle the functional role of large carnivores in top–down control in different environmental contexts. Second, we conducted four small-scale ecosystem simulation experiments to understand direct and indirect changes in food-web structure under different environmental conditions. We found that the removal of top–down control exerted by large carnivores (> 21 kg) can trigger large trophic cascades, leading to an overall decrease in autotroph biomass globally. Furthermore, the loss of large carnivores resulted in an increase of mesopredators. The magnitude of these changes was positively related to primary productivity (NPP), in line with the ‘exploitation ecosystem hypothesis’. In addition, we found that seasonality in NPP dampened the magnitude of change following the removal of large carnivores. Our results reinforce the idea that large carnivores play a fundamental role in shaping ecosystems, and further declines and extinctions can trigger substantial ecosystem responses. Our findings also support previous studies suggesting that natural ecosystem dynamics have been severely modified and are still changing as a result of the widespread decline and extinction of large carnivores.

New species introductions can change lakes rapidly by directly affecting trophic levels through predator–prey interactions or by indirectly affecting ecosystem structure and function. When ...

Fire and mammalian grazers both consume grasses, and feedbacks between grass species, their functional traits, and consumers have profound effects on grassy ecosystem structure worldwide, such that savanna and grassland states determined by fire or grazing can be considered alternate states. These parallel savanna-forest alternate states, which likewise have myriad cascading ecosystem impacts.

Aim: Light Detection And Ranging (LiDAR) is a promising remote sensing technique for ecological applications because it can quantify vegetation structure at high resolution over broad spatial extents. Using country-wide airborne laser scanning (ALS) data, we test to what extent fine-scale LiDAR metrics capturing low vegetation, medium-to-high vegetation and landscape-scale habitat structures can explain the habitat preferences of threatened butterflies at a national extent. Location: The Netherlands. Methods: We applied a machine-learning (random forest) algorithm to build species distribution models (SDMs) for grassland and woodland butterflies in wet and dry habitats using various LiDAR metrics and butterfly presence–absence data collected by a national butterfly monitoring scheme. The LiDAR metrics captured vertical vegetation complexity (e.g., height and vegetation density of different strata) and horizontal heterogeneity (e.g., vegetation roughness, microtopography, vegetation openness and woodland edge extent). We assessed the relative variable importance and interpreted response curves of each LiDAR metric for explaining butterfly occurrences.Results: All SDMs showed a good to excellent fit, with woodland butterfly SDMs performing slightly better than those of grassland butterflies. Grassland butterfly occurrences were best explained by landscape-scale habitat structures (e.g., open patches, microtopography) and vegetation height. Woodland butterfly occurrences were mainly determined by vegetation density of medium-to-high vegetation, open patches and woodland edge extent. The importance of metrics generally differed between wet and dry habitats for both grassland and woodland species. Main conclusions: Vertical variability and horizontal heterogeneity of vegetation structure are key determinants of butterfly species distributions, even in low-stature habitats such as grasslands, dunes and heathlands. The information content of low vegetation LiDAR metrics could further be improved with country-wide leaf-on ALS data or surveys from drones and terrestrial laser scanners at specific sites. LiDAR thus offers great potential for predictive habitat distribution modelling and other studies on ecological niches and invertebrate–habitat relationships.

International audience; With about 11,100 islands and islets of which ca. 250 are regularly inhabited by human, the Mediterranean Sea represents one of the regions of the world with the most islands and archipelagos. These numerous islands represent a significant component of the Mediterranean biodiversity, notably with the presence of range-restricted species and peculiar vegetation types. The aim of this review is to provide a balanced view of this highly diverse phytoecological heritage, but also taking into account the medium sized islands and the smaller ones that have not been highlighted so far. Mediterranean islands constitute both a museum for ancient lineages (paleoendemic taxa) and cradle for recent plant diversification. The complex historical biogeography (paleogeographical events of the Neogene, Messinian salinity crisis, climatic and eustatic changes of the Pleistocene, influence of glacial events) has profoundly influenced the current patterns of plant diversity. These insular landscapes were also precociously impacted by prehistoric man, possibly by Neanderthals. Among the 157 large Mediterranean islands (i.e. with a surface area exceeding 10 km 2), 49 have a surface greater than 100 km 2 .The main patterns anddynamics of vegetationon the largests islands (Balearic Islands, Corsica, Sardinia, Sicily, Croatian islands, Greek islands, Crete, Cyprus) are summarized. Then, the specific ecosystem functioning (disturbance, plant-animal interactions) and vegetation structures of the small Mediterranean islands (i.e. a surface area less than 10 km 2 or 1000 ha), are highlighted by evoking successively the small rocky islands, the volcanic ones, and the sandy and flat islands. Owing to their uniqueness and fragility, Mediterranean islands urgently need some integrated and ambitious conservation planning, aiming at the long-term preservation of their outstanding biotic and cultural heritage.

Science is a search for patterns but there are few cross-habitat patterns in ecology. We propose key questions following the findings of consistent scaling of abundance versus body mass from bacteria to earthworms and whales, based on an almost forgotten study of soils and a well-known one from the open ocean.

This research is part of POLARCSIC activities.-- 15 pages, 9 figures, 3 tables, supplementary data https://doi.org/10.1016/j.jmarsys.2019.103268, The flow of non-living carbon (detritus) is considered an important process because it connects ecosystems and fuels benthic communities. In Norwegian kelp forests, 90% of the kelp production is exported to adjacent ecosystems where it can play a significant role in shaping benthic communities. We quantified the major structural and functional traits of an Arctic deep-sea ecosystem associated with kelp exports and assessed the ecological role of kelp export into the deep-sea system. We first developed a food-web model using the Ecopath with Ecosim (EwE) approach to represent the state of the deep (450 m) ecosystem of the Malangen fjord (Northern Norway) in 2017. Subsequently, we used the temporal dynamic model Ecosim to explore the structure and functioning traits of a theoretical deep-sea ecosystem projecting a decrease of kelp detritus biomass reaching the deep-sea ecosystem. Overall, our findings reveal that kelp detritus from shallow coastal areas has a small but noticeable role structuring the deep-sea ecosystem of Malangen. The temporal simulations show important differences depending on the application of mediating effects, which allow considering the detritus as a mediating group in prey-predator interaction, in addition to its direct role in trophic relationships. When mediating effects are applied, biomass increases for benthopelagic shrimps and suprabenthos groups and decreases for rays and skates, velvet belly, rabbitfish and other commercial demersal fishes under the low kelp detritus scenarios. Biomass-based and trophic-based indicators reveal a noticeable impact on the deep-sea ecosystem structure due to depletion of kelp detritus. To further assess future changes of the Arctic deep-sea ecosystems, dependencies with adjacent ecosystems, such as kelp detritus production, should be included, This work was funded by MARINFORSK Norwegian Research Council through the KELPEX project (NRC Grant no. 255085/E40). [...] MC acknowledges partial funding by the European Union's Horizon research program grant agreement No 689518 for the MERCES project, With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

This paper presents the assessment of a change in the shelf ecosystem state under biological pollution based on a mathematical model of the annual cycle of its main pelagic parameters. The Northern Caspian region was chosen as an example and the impact of invader Mnemiopsis leidyi was taken as a biological pollution. Using the previously calculated annual cycle of the main pelagic parameters of the ecosystem, we decomposed the model, taking into account a new block responsible for the functioning of the invader. Simulations of three predefined scenarios of external conditions showed the effectiveness of the model for solving problems of changes in the ecosystem structure and predicting the consequences of the presence of the aggressive invader.

The effects of the combined roles of abiotic and biotic factors defining foodweb structure are often ignored. In aquatic systems, abiotic variables can regulate food webs through bottom-up ...

The forage fish communities of the Laurentian Great Lakes continue to experience changes that have altered ecosystem structure, yet little is known about how they partition resources. Seasonal, spatial, and body size variation in δ13C and δ15N was used to assess isotopic niche overlap and resource and habitat partitioning among the five common offshore Lake Ontario forage fish species (n = 2037; alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), round goby (Neogobius melanostomus), and deepwater (Myoxocephalus thompsonii) and slimy (Cottus cognatus) sculpins). Round goby had the largest isotopic niche (6.1‰2, standard ellipse area), followed by alewife (3.4‰2), while rainbow smelt, slimy sculpin, and deepwater sculpin had the smallest and similar niche size (1.7‰2–1.8‰2), with only the sculpin species showing significant isotopic niche overlap (>63%). Stable isotopes in alewife, round goby, and rainbow smelt varied with location, season, and size, but did not vary in the sculpin species. Lake Ontario forage fish species have partitioned food and habitat resources, and non-native alewife and round goby have the largest isotopic niche, suggestive of a boarder ecological niche, and may contribute to their current high abundance.

Disturbance can play an important role in structuring stream food webs. Although floods have received the greatest attention as a disturbance agent in rivers, wildfire — which can strongly influence fluvial ecosystem structure and function — may also drive consumer trophic dynamics. We measured the relative effects of wildfire, hydrologic disturbance, ecosystem size, and canopy openness (as a proxy for in-stream productivity) on trophic position and reliance on aquatically-derived nutritional subsidies of riparian spiders of the family Tetragnathidae along two rivers on the west slope of the Sierra Nevada in California, USA. Ecosystem size received strong support as an environmental determinant of both trophic measures, with variability in flood magnitude emerging as an important mechanism linking ecosystem size and trophic responses. Piecewise linear regression revealed significant breakpoints in spider trophic position and reliance on aquatically-derived nutritional subsidies that were related to thresholds in fire extent within the catchment. These nonlinear relationships with wildfire may lend additional insight into the potential interactions among ecosystem size, productivity, and disturbance that determine stream–riparian food-web architecture.

Despite some controversy, a wide range of research across multiple taxa have established that carnivores strongly influence prey population dynamics both through direct offtake and indirect risk effects. Because of these powerful top-down effects carnivores can influence ecosystems across multiple trophic levels. Here we discuss research addressing carnivore direct- and indirect effects on prey, and how these effects can influence overall ecosystem structure and function.

A food web topology describes the diversity of species and their trophic interactions, i.e. who eats whom, and structural analysis of food web topologies can provide insight into ecosystem structure and function. It appears simple, at first sight, to list all species and their trophic interactions. However, the very large number of species at low trophic levels and the impossibility to monitor all trophic interactions in the ocean makes it impossible to construct complete food web topologies. In practice, food web topologies are simplified by aggregating species into groups termed trophospecies. It is not clear though, how much simplified versions of food webs retain the structural properties of more detailed networks. Using the most comprehensive Barents Sea food web to date, we investigate the performance of methods to construct simplified food webs using three approaches: taxonomic, structural and regular clustering. We then evaluate how topological properties vary with the level of network simplification. Results show that alteration of food web structural properties due to aggregation are highly sensitive to the methodology used for grouping species and trophic links. In the specific case of the Barents Sea, we show that it is possible to preserve key structural properties of the original complex food web in simplified versions when using taxonomic or structural clustering combined with intermediate 25% linkage for trophic aggregation.

Alien species and bottom trawl fisheries are of significant concern in the Eastern Mediterranean as both can put pressure on coastal systems whilst some alien species also constitute an important component of the trawl catches. Using an Ecopath model representing the Gulf of Mersin (Northeastern Mediterranean) for the period September 2009 to September 2013, this study describes the impacts of alien species and bottom trawl fisheries on the structure and functioning of this Northeastern Mediterranean food web. Our results show that the increase in alien species has had an important ecological impact on ecosystem structure and function. The alien species have had mostly negative impacts on native taxa, and trawl fisheries may have helped some alien species gain an advantage over native species, particularly at lower trophic levels. The Mixed Trophic Impact analysis showed that trawling and trawl discards had a noticeable direct and indirect impact on the food web, to the extent that trawling now affects the ecological role of the alien species. The cumulative overall impact of alien demersal functional groups on the pelagic domain, and vice versa suggest that alien species now play a role in benthic-pelagic coupling, and that this role is mediated by the fisheries. These results support the idea that alien species and trawling are now both important factors in structuring the Northeastern Mediterranean food web. It will thus be critical to consider both factors, as well as their interactions, when developing ecosystem-based management approaches for the region. © 2019 Elsevier B.V. 2014-2 Türkiye Bilimsel ve Teknolojik Araştirma Kurumu Here we present a part of the PhD thesis of Ismet SAYGU, funded by the Scientific and Technological Research Council of Turkey (TUBITAK) on the TUBITAK 2214-A Programme ( 2014-2 ) and supported by the Scottish Association for Marine Science (SAMS) as host institution. In addition, the main data of this study was obtained from the project 109O684 financed by TUBITAK . Ismet Saygu would like to address a special thanks to Barış Salihoğlu, Ekin Akoğlu, Nazlı Demirel, Xavier Corrales, Sinan Mavruk, Marieke Steuben and Sam Jones for their advice. Appendix A

3D-imaging technologies provide measurements of terrestrial and aquatic ecosystems’ structure, key for biodiversity studies. However, the practical use of these observations globally faces practical challenges. First, available 3D data are geographically biased, with significant gaps in the tropics. Second, no data source provides, by itself, global coverage at a suitable temporal recurrence. Thus, global monitoring initiatives, such as assessment of essential biodiversity variables (EBVs), will necessarily have to involve the combination of disparate data sets. We propose a standardized framework of ecosystem morphological traits – height, cover, and structural complexity – that could enable monitoring of globally consistent EBVs at regional scales, by flexibly integrating different information sources – satellites, aircrafts, drones, or ground data – allowing global biodiversity targets relating to ecosystem structure to be monitored and regularly reported.

Background Use of skin personal care products on a regular basis is nearly ubiquitous, but their effects on molecular and microbial diversity of the skin are unknown. We evaluated the impact of four beauty products (a facial lotion, a moisturizer, a foot powder, and a deodorant) on 11 volunteers over 9 weeks. Results Mass spectrometry and 16S rRNA inventories of the skin revealed decreases in chemical as well as in bacterial and archaeal diversity on halting deodorant use. Specific compounds from beauty products used before the study remain detectable with half-lives of 0.5–1.9 weeks. The deodorant and foot powder increased molecular, bacterial, and archaeal diversity, while arm and face lotions had little effect on bacterial and archaeal but increased chemical diversity. Personal care product effects last for weeks and produce highly individualized responses, including alterations in steroid and pheromone levels and in bacterial and archaeal ecosystem structure and dynamics. Conclusions These findings may lead to next-generation precision beauty products and therapies for skin disorders. Electronic supplementary material The online version of this article (10.1186/s12915-019-0660-6) contains supplementary material, which is available to authorized users.

This review provides a broad conceptual overview of different approaches to measuring marine ecosystem condition and guidance for framework development (particularly relevant for developing countries). The objectives were to review definitions of ecosystem condition and identify the core approaches and key challenges within the research area. Furthermore, we reviewed the advantages and disadvantages of different indicators that can be used for condition assessments. A semi-systematic approach drawing from more than 300 studies covering a broad range of methods was followed. Generally, definitions of ecosystem condition are based on known changes to the ecosystem, but ultimately, they should align with the definition of an ecosystem and consider ecosystem structure and functioning. As far as possible, the definition should relate an observed state to a reference condition or ecological target. Importantly, definitions of condition should be practical, scalable and always provided when conducting condition assessments. Five indicator categories were identified including pressures, physical parameters, biological structure, functional structure and ecological models. Indicators mostly focus on drivers of change (i.e. ex situ pressures) or the structure of the ecosystem, as these data are easier to obtain. While valuable, these classes of indicators can only provide an indirect appraisal of ecosystem functioning in instances where the relationship between pressure, structure and functioning are known. Indicators that measure structure and functioning of an ecosystem can be used to directly report on condition; however, the data (and monitoring) requirements make them impractical in most instances. Ideally, integrated assessments, that measure indicators from all indicator categories, should be prioritised to provide a comprehensive overview of condition. However, this often requires transdisciplinary collaboration, substantial research capacity (and associated funding) and time to collect the necessary data. An alternative is to select a few strategic indicators that can provide data to address the definition of ecosystem condition and at the same time provide a feasible approach to address the project specific research objectives. Where possible, a data-derived approach should be followed as in situ measurements have potential to improve the understanding of impacts of anthropogenic pressures on ecosystem functioning, and in turn facilitate better management of human activities and enhance ecosystem functioning.

Nutrient availability in terrestrial ecosystems has been found to vary along regional climatic and soil gradients and drive variation in plant community composition and vegetation structure. However, more local biotic feedbacks also affect nutrient availability, but their importance in determining vegetation structure relative to regional drivers is yet unclear. Mesic African savannas form a transition zone between the dry grasslands with relatively low nitrogen availability (indicated by low plant N:P ratios) and the wet woodlands of the continent characterized by relatively low phosphorous availability (high plant N:P ratios). They host strong feedback mechanisms of both vegetation and consumers, where large grazers can create short grazing lawns that alternate over short distances with tall fire-dominated bunch grasslands, and patches dominated by woody species with abundant macrodetritivores. Here, we test if such local biotic interactions can overrule regional, landscape-level drivers of plant nutrient availability. In a South African savanna, we find that plant N:P ratios, N and P resorption efficiencies and proficiencies, were indeed much stronger affected by small-scale biotic-created heterogeneity than by a regional rainfall gradient (530-830mmyr(-1)). Furthermore, we observe that differences in N:P ratios between vegetation structural types are not caused by simple differences in inherent plant traits. This suggests that availability of N and P to plants is strongly contingent on the local biotic interplay between different vegetation structural types and within-system feedbacks linked to each vegetation type. The regional rainfall gradient did affect nutrient availability, but mainly through its effect on the relative distribution of the different vegetation structural types thus setting the range of possible outcomes of biotic interactions.Synthesis. Regional and global studies that model savanna carbon and nutrient cycling only on the basis of regional gradients in soil and climatic conditions may insufficiently capture the dominant ecosystem processes involved.

00001 WOS:000389304800009; International audience; Climate change is inducing deep modifications in local communities worldwide as a consequence of individualistic species range shifts. Understanding how complex interaction networks will be reorganized under climate change represents a major challenge in the fields of ecology and biogeography. However, forecasting the potential effects of climate change on local communities, and more particularly on food-web structure, requires the consideration of highly structuring processes, such as trophic interactions. A major breakthrough is therefore expected by combining predictive models integrating habitat selection processes, the physiological limits of marine species and their trophic interactions. In this study, we forecasted the potential impacts of climate change on the local food-web structure of the highly threatened Gulf of Gabes ecosystem located in the south of the Mediterranean Sea. We coupled the climatic envelope and habitat models to an allometric niche food web model, hence taking into account the different processes acting at regional (climate) and local scales (habitat selection and trophic interactions). Our projections under the A2 climate change scenario showed that future food webs would be composed of smaller species with fewer links, resulting in a decrease of connectance, generality, vulnerability and mean trophic level of communities and an increase of the average path length, which may have large consequences on ecosystem functioning. The unified framework presented here, by connecting food-web ecology, biogeography and seascape ecology, allows the exploration of spatial aspects of interspecific interactions under climate change and improves our current understanding of climate change impacts on local marine food webs.

Invasive species alter ecosystem structure and function when they establish in new habitats. Although preventing or managing invasions is extremely important for maintaining biodiversity, doing so is difficult and requires efficient intervention. Remote monitoring of free-living animals with electronic tags (i.e. tags that transmit data remotely or log them for future retrieval) can contribute important knowledge about invasive animal biology. A quantitative literature review identified instances in which electronic tagging has contributed to studying invasions. Electronic tags were generally used for one of four purposes: (1) characterize spatial ecology; (2) identify interactions; (3) assess risk potential; or (4) evaluate management options. Overall, electronic tags have considerable potential for developing, refining, and evaluating invasion management strategies that contribute to conservation efforts. We explore the role of electronic tags as a component of integrated control program design and implementation for invasive animals.

Secondary production is an integrative measure of the accumulation of heterotrophic biomass through time and can be a valuable tool to design, implement, and assess restoration initiatives. To highlight applications of secondary production in restoration contexts, we identify recent papers from the literature, use these to make generalizations about how the concept is applied, and examine why it may not be utilized more commonly. We identified 21 papers that empirically quantified secondary production to compare pre/post-restoration or assess restored sites relative to reference ones. Every study was aquatic, suggesting that secondary production is an underutilized tool in terrestrial restoration studies. We discuss various ways that food web perspectives inform restoration secondary production outcomes, such as through shifts in aquatic basal resource pools and alleviation of nutrient limitation, changes which ripple through food webs supporting higher trophic level production. Despite challenges inherent to calculating secondary production, the approach holds much promise—it is a composite metric simultaneously reflecting components of ecosystem structure and dynamics that restoration initiatives target.

1. Climate change is a world-wide threat to biodiversity and ecosystem structure, functioning and services. To understand the underlying drivers and mechanisms, and to predict the consequences for nature and people, we urgently need better understanding of the direction and magnitude of climate change impacts across the soil–plant–atmosphere continuum. An increasing number of climate change studies are creating new opportunities for meaningful and high-quality generalizations and improved process understanding. However, significant challenges exist related to data availability and/or compatibility across studies, compromising opportunities for data re-use, synthesis and upscaling. Many of these challenges relate to a lack of an established ‘best practice’ for measuring key impacts and responses. This restrains our current understanding of complex processes and mechanisms in terrestrial ecosystems related to climate change. 2. To overcome these challenges, we collected best-practice methods emerging from major ecological research networks and experiments, as synthesized by 115 experts from across a wide range of scientific disciplines. Our handbook contains guidance on the selection of response variables for different purposes, protocols for standardized measurements of 66 such response variables and advice on data management. Specifically, we recommend a minimum subset of variables that should be collected in all climate change studies to allow data re-use and synthesis, and give guidance on additional variables critical for different types of synthesis and upscaling. The goal of this community effort is to facilitate awareness of the importance and broader application of standardized methods to promote data re-use, availability, compatibility and transparency. We envision improved research practices that will increase returns on investments in individual research projects, facilitate second-order research outputs and create opportunities for collaboration across scientific communities. Ultimately, this should significantly improve the quality and impact of the science, which is required to fulfil society's best practice, coordinated experiments, data management and documentation, ecosystem, experimental macroecology, methodology, open science, vegetation This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2019 The Authors. Methods in Ecology and Evolution published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Social-ecological systems in the Mediterranean Basin are characterised by high biodiversity and a prolonged cultural influence, leading to the co-evolution of these systems. The unique characteristics of Mediterranean social-ecological systems, current pressures leading to a decline in ecosystem services, and the need for coordinated action are recognised by policies promoting the protection and sustainable use of the region’s heritage. Ecosystem assessments provide valuable information on the capacity of the Mediterranean Basin to ensure the well-being of its population. However, most assessments simplify the complexity of these systems, which may lead to inaccurate ecosystem services supply and flow estimations. This paper uses the Driver-Pressure-State-Impact-Response (DPSIR) model to guide an expert consultation that identifies the key characteristics of the Mediterranean social-ecological systems and analyses how these should be included in ecosystem assessments. Data collection was carried out through expert consultation with ecosystem services researchers. Multiple sources of complexity were identified, including the relationship between historical human activities, biodiversity spatio-temporal patterns, as well as the seasonal and long-term variability in ecosystem services. The importance of incorporating this complexity in ecosystem assessments for evidence-based decision-making is identified, suggesting that there is a need to adapt assessment approaches for the Mediterranean Basin social-ecological systems., This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 809988. JVRD was supported by the Government of Asturias and FP7-Marie Curie-COFUND European Commission program (Grant ‘Clarín’ ACA17-02). SdM benefited from a Serra-Húnter Fellowship provided by the Generalitat of Catalonia.

Both ecosystem structure and functioning determine ecosystem status and are important for the provision of goods and services to society. However, there is a paucity of research that couples functional measures with assessments of ecosystem structure. In mid-sized and large rivers, effects of restoration on key ecosystem processes, such as ecosystem metabolism, have rarely been addressed and remain poorly understood. We compared three reaches of the third-order, gravel-bed river Ruhr in Germany: two reaches restored with moderate (R1) and substantial effort (R2) and one upstream degraded reach (D). Hydromorphology, habitat composition, and hydrodynamics were assessed. We estimated gross primary production (GPP) and ecosystem respiration (ER) using the one-station open-channel diel dissolved oxygen change method over a 50-day period at the end of each reach. Moreover, we estimated metabolic rates of the combined restored reaches (R1 + R2) using the two-station open-channel method. Values for hydromorphological variables increased with restoration intensity (D

Evaluation of the ecological effects of eco-compensation policies helps analyze policy rationality and feasibility and provides scientific and practical bases for perfecting eco-compensation systems. Taking the key ecological function area of the Loess Plateau, China as a case study, we have evaluated ecosystem responses to the Grain-for-Green Project that commenced in 1999. Six indicators were selected to assess changes in ecosystem structure, quality and function. The results showed that implementation of the Grain-for-Green Project has reduced sloping cropland by 1571 km2 and increased ecological land by 1337 km2. The increase in ecological land alters ecosystem structures across the study area and the decline in sloping cropland reduces farming activity interference; both of these are conducive to the restoration of natural vegetation. From 2000 to 2010, the vegetation cover of grassland, desert and forest ecosystems increased 10.89%, 8.34% and 4.24% respectively and average NPP rose 51%, wi...

International audience; In the context of present global changes, interest in understanding how systems respond to anthropogenic environmental pressures and stress has increased. Indices that characterize ecosystem state are helpful tools for the interpretation of ecosystem responses. The central question is how to link these responses to ecosystem structure and functioning and to quantify ecosystem persistence, resistance or resilience. Quantification and characterization of trophic networks by ecological network analysis (ENA) indices is proceeding rapidly, especially in the field of coastal ecology. In this contribution, we review several theories that relate ecosystem structure and function to stability. The structure and functioning of ecosystems change during the maturation of ecosystems. In the first section, the maturation of ecosystems is described using thermodynamics. In the second and third parts of this paper, we define some concepts for analysing structure and functioning of food webs and discuss their relation to stability. In the last section, we describe three ENA indices and their link to stability. We demonstrate that ENA provides powerful tools for describing local stability, combining quantitative and qualitative concepts. However, it remains incomplete for describing real conservation cases that combine local and global stability. © 2015 Elsevier Ltd. All rights reserved.

Disturbances are fundamental components of ecosystems and, in many cases, a dominant driver of ecosystem structure and function at multiple spatial and temporal scales. While the effect of any one disturbance may be relatively well understood, multiple interacting disturbances can cause unexpected disturbance behavior (e.g., larger extents), altered return likelihoods, or reduced ecosystem resilience and regime shifts. Given the long‐lasting implications of such events, and the potential for changes in disturbance rates driven by climate change and increasing anthropogenic pressures, developing a broad conceptual understanding and some predictive ability regarding the likelihood of interactions between disturbances is crucial. Through a broad synthesis of the literature, and across multiple biomes, disturbance interactions are placed into a unified framework around the concept of changing ecosystem resistance (“linked interactions,” alterations to likelihood, extent, or severity) or ecosystem resilience (“compound interactions,” alterations to recovery time or trajectory). Understanding and predicting disturbance interactions requires disaggregating disturbances into their constituent legacies, identifying the mechanisms which drive disturbances behavior (or ecosystem recovery), and determining when and where those mechanisms might be altered by the legacies of prior disturbances. The potential for cascading effects is discussed, by which these interactions may extend the reach of anthropogenic or climate change‐induced alterations to disturbances beyond what is currently anticipated. Finally, several avenues for future research are outlined, as suggested from the current literature (and areas in which that literature is lacking). These include the potential for cross‐scale interactions and changing scale‐driven limitations, further work on cascading effects, and the potential for cross‐biome comparisons. Disturbance interactions have the potential to cause large, nonlinear, or unexpected changes in ecosystem structure and functioning; finding generality across these complex events is an important step in predicting their occurrence and understanding their significance.

Creation of the National Ecological Observatory Network (NEON) provides unparalleled opportunities for continental-scale research and synthesis in aquatic sciences. Organizers of the NEON aquatic network will equip sites at 29 streams or small rivers across bioclimatic regions of the USA to measure O2 dynamics, aquatic community structure, and aquatic chemistry for up to 3 decades. Data will be collected via a suite of sensors and traditional measurements of a wide range of variables with standardized techniques. The availability of such data will usher in a new era for aquatic scientists, who can use the data to understand the influence of major drivers of stream ecosystem structure and function at regional to continental scales. This rich data stream also will present challenges for the aquatic community. These challenges include interpreting field measurements at distant sites, analysis and management of large data sets, development of appropriate tools for synthesis, and changes in the culture...

Parrots (Psittaciformes) have been viewed as efficient consumers of the reproductive structures of plants. Consequently, parrots have been excluded from studies focusing on plant–animal mutualistic relationships as they have been considered only as plant antagonists. This prevailing view is challenged, however, by recent studies showing that (1) several parrot species are the main seed dispersers of some plant species through stomatochory; (2) the proportion of seeds removed and dispersed to long distances is high in some plant–parrot systems; (3) seeds dispersed by parrots are able to produce seedlings, even in some cases after being partially consumed; (4) tiny seeds are also legitimately dispersed by parrots through endozoochory; (5) seeds dropped by parrots under the mother tree can be consumed and secondarily dispersed by a variety of other species; and (6) parrots can also pollinate and heal their food plants by consuming their parasites. Through both antagonistic and mutualistic interactions with their food plants, parrots can exert cascading effects on the plants’ life cycles and shape the structure and functioning of ecosystems. The later was evaluated by a few studies showing how parrots may shape vegetal landscapes by influencing the spatial distribution and demography of their food plants and vegetal communities. On the other hand, mutualistic interactions lead to an increase of the parrot community robustness when facing the loss of plant species. We provide guidance for further research on the multiple plant–parrot interactions, also encouraging the assessment of how the ongoing decline and extirpation of parrot populations may cause regional losses of key ecological functions., This review benefited from our own work on parrots, funded by Fundación Biodiversidad, Fundación Repsol, World Parrot Trust, a Severo Ochoa award (to F.H.), and ParrotNet COST Action Group, conducted in collaboration with a number of researchers.

The top-down effects of predators on ecosystem structure and dynamics have been studied increasingly. However, the nature and consequence of trophic interactions between upper-trophic-level predators have received considerably less attention. This is especially the case in marine systems due to the inherent challenges of studying highly mobile marine species. Here we describe the first documentation of asymmetrical intraguild predation by a pinniped predator on a mid-sized predatory shark. The report is based on direct observations in South African waters, in which free-swimming blue sharks Prionace glauca were captured and partially consumed by Cape fur seals Arctocephalus pusillus pusillus. These observations are important not just for understanding the interactions between these two species but more broadly for their implications in understanding the trophic ecology of pinnipeds, many populations of which have increased while numerous shark populations have declined.

Similarities in planning, development and culture within urban areas may lead to the convergence of ecological processes on continental scales. Transdisciplinary, multi-scale research is now needed to understand and predict the impact of human-dominated landscapes on ecosystem structure and function.

Soil surface communities comprised of cyanobacteria, mosses, liverworts, fungi, eukary-otic algae and lichens (biological soil crusts or biocrusts) are a conspicuous and importantbiotic component of many terrestrial ecosystems worldwide, from the tropics to the poles,in which they strongly influence ecosystem structure and processes (Belnap and Lange2003). Biocrusts show the resistance and resilience of life under extreme conditions as wellas a remarkable adaptation to the combinations of different climatic factors throughout alllatitudes. As such, it is not surprising that multiple aspects of the biology and taxonomy ofbiocrust constituents have been studied for many years (Belnap and Lange 2003). How-ever, the interest of the scientific community in biocrusts has grown exponentially over thelast two decades, and a new wave of research on the ecological roles of biocrusts has beenconducted during this period (e.g. Lindo and Gonzalez 2010; Castillo-Monroy and Maestre2011; Maestre et al. 2011; Mager and Thomas 2011; Pointing and Belnap 2012; Bu et al.2013 for recent reviews). Research on all aspects of biocrust biology and their influence onecosystems, traditionally performed by researchers in a few countries, such as the USA,Australia, Israel, and Germany has become a truly global research endeavor, with theemergence of many groups in countries such as China, Spain, and Mexico (Castillo-Monroy and Maestre 2011).The biocrust research community is more interconnected than ever before, as evidencedby the multiple collaborations that are being established among the different groups, by theongoing preparation of a new book on the status of the field featuring authors from all the

Using natural streams as references against which ecosystem structure and function could be compared, we examined the short-term (1–3 years) and long-term (14 years) effectiveness of a 3.4 km constructed stream in the Northwest Territories, Canada. The constructed stream variously showed little to marked improvements 14 years after construction (2011), relative to 1998–2000 and to reference streams, depending on the stream attribute. Many attributes related to stocks of organic matter remained well below reference levels in the constructed stream after 14 years. Leaf matter processing rates increased in the constructed stream to the point of convergence with reference streams in 2011, but the latter still had superior leaf retention abilities. By Year 14, benthic invertebrate composition in the constructed stream showed some convergence with reference streams, although densities generally lagged, especially in riffles. In 2011, growth of young-of-the-year Arctic grayling (Thymallus arcticus) from the constructed stream was substantially greater relative to 1998–2001, but remained well below contemporary reference levels. Our mixed results raise questions about the definition and time scale of successful restoration.

In September 2011, the University of Essex, UK, hosted an interdisciplinary conference, Mathematical and Theoretical Ecology 2011 (MATE 2011), with the theme of ‘Linking models with ecological processes’. The aim of the meeting was to create discussion and debate between modellers and empiricists working in ecology. A wide range of topics were discussed at the meeting including evolutionary and community models of ecosystem structure, epidemiological models, non-linear models of population dynamics, spatiotemporal models, individual and collective movement behaviour, and applications of ecological models to engineering problems. In this introductory article, we provide a report of the MATE 2011 meeting, and briefly review the most recent relevant research in the fields of mathematical and theoretical ecology. We introduce and summarise the eight contributed articles that were selected for this special issue. The diverse range of topics and the wide range of mathematical, statistical and computational tools used illustrate the broad appeal and depth of research in the rich field of mathematical and theoretical ecology.

Marine bacteria are known to produce a wide variety of structurally diverse and biologically active secondary metabolites. Considerably less is known about the ecological functions of these compounds, in part due to methodological challenges associated with this field of research. Here, we review the antagonistic activities mediated by marine bacteria with a focus on activities linked to structurally defined secondary metabolites. Bacterial antagonism has been documented against other marine bacteria as well as eukaryotes, and includes antibiosis, the inhibition of quorum sensing, larval settlement deterrence, and defense against predation. These compounds likely play important ecological roles that ultimately affect ecosystem structure and function, however, much remains to be learned before these roles can be fully appreciated. Recent technological advances coupled with a better understanding of the diverse processes mediated by secondary metabolites provide new opportunities to expand our understanding of the chemical ecology of bacterial antagonism in the marine environment.

Road reclamation has emerged as an integral part of ecological restoration strategies, particularly on public lands. However, there are no consistent techniques for how road reclamation should be implemented to restore ecosystem structure and function. Resource managers are hindered by critical research gaps regarding the linkages between, as well as the effects of different restoration actions on, above- and belowground ecological and hydrological properties. In the western US, we examined how two road reclamation methods (recontouring and abandonment) affect ecosystem properties relative to “never-roaded” areas. Recontoured and abandoned sites displayed similar aboveground properties but exhibited notable differences in below-ground properties, including soil hydraulic conductivity, organic matter, total carbon, and total nitrogen, among others. Our findings suggest that recontouring can dramatically accelerate recovery of above- and belowground properties so they resemble never-roaded reference conditi...

Aim Climate change and loss of apex predators can affect ecosystem structure and function through modified limitation processes. We investigated, on a continental scale, whether mesopredator abunda ...

During the past century, the field of fisheries oceanography has dominated the study of population connectivity in marine environments. The influence of physical and biological processes and their relationship to transport and retention of early life history stages has been central in providing insight into population structuring and connectivity. However, the focus on dispersive early life history stages has meant that the role of adults has received less attention and is not fully understood or appreciated. We argue that adults play a vital role in population connectivity for a wide range of marine taxa and hypothesize that adult-mediated population connectivity commonly results in a diverse array of population structuring. Two case-studies on winter skate, Leucoraja ocellata, and winter flounder, Pseudopleuronectes americanus, are presented to illustrate the role adults play in marine connectivity at both broad and fine scales, respectively. Indeed, if adults are important for population connectivity, we argue that the role of larval processes is conditional on adult choice and only management and research pursuits that integrate the full life cycle of species will capture the full dynamics of metapopulation connectivity. Failure to include the roles of adults can lead to misinterpretation of the causes and consequences of changes in ecosystem structure and fisheries productivity.

1.Trophic cascade theory predicts that apex predators structure ecosystems by regulating mesopredator and herbivore abundance and behaviour. Studies on trophic cascades have typically focused on short linear chains of species interactions. A framework that integrates more realistic and complex interactions is needed to make broader predictions on ecosystem structuring. 2.Network analysis is used to study food webs and other types of species interaction networks. These often comprise large numbers of species but rarely account for multiple interaction types and strengths. Here we develop an intermediate complexity theoretical framework that allows specification of multiple interaction types and strengths for the study of trophic cascades. This ecological network is designed to suit data typically derived from field-based studies. The trophic cascade network contains fewer nodes than food webs, but provides semi-weighted directional links that enable different types of interactions to be included in a single model. 3.We use this trophic cascade network model to explore how an apex predator shapes ecosystem structure in an Australian arid ecosystem. We compared two networks that contrasted in the dominance of an apex predator, the dingo (Canis dingo), using published results ranking the direction and strength of key interactions. Nodes and links interacted dynamically to shape these networks. We examined how changes to an apex predator population affects ecosystem structure through their direct and indirect influences on different components of this ecological community. 4.Under strong apex predator influence, the network structure was denser and more complex, even, and top-down driven; and dingo predation and soil commensalism formed denser interactive modules. Under weak apex predator influence (e.g. reflecting predator control) the resulting network structure was frayed, with mesopredator predation and grazing forming modules. 5.Our study demonstrates that networks of intermediate complexity can provide a powerful tool for elucidating potential ecosystem-wide effects of apex predators, and predicting the consequences of management interventions such as predator control. Integrating trophic cascades, with their array of complex interactions, with the three-dimensional structure of ecological networks, has the potential to reveal ‘ecological architecture’ that neither captures on its own. This article is protected by copyright. All rights reserved.

One of the twenty-first century's greatest environmental challenges is to recover and restore species, habitats and ecosystems. The decision about how to initiate restoration is best-informed by an understanding of the linkages between ecosystem components and, given these linkages, an appreciation of the consequences of choosing to recover one ecosystem component before another. However, it remains difficult to predict how the sequence of species' recoveries within food webs influences the speed and trajectory of restoration, and what that means for human well-being. Here, we develop theory to consider the ecological and social implications of synchronous versus sequential (species-by-species) recovery in the context of exploited food webs. A dynamical systems model demonstrates that synchronous recovery of predators and prey is almost always more efficient than sequential recovery. Compared with sequential recovery, synchronous recovery can be twice as fast and produce transient fluctuations of much lower amplitude. A predator-first strategy is particularly slow because it counterproductively suppresses prey recovery. An analysis of real-world predator-prey recoveries shows that synchronous and sequential recoveries are similarly common, suggesting that current practices are not ideal. We highlight policy tools that can facilitate swift and steady recovery of ecosystem structure, function and associated services.

Evidence of segregation in foraging habitat has been demonstrated in some top marine predators, including cetaceans, pinnipeds and seabirds. However, most data are not adequate to assess differences relating to body size or seasonal influences. This has implications for quantitative modelling of population-level predator–prey interactions and ecosystem structure. We examined potential influence of body size and ‘fatness’ on the foraging trip characteristics of a top marine predator, the Atlantic grey seal (Halichoerus grypus), in southwest Ireland within the framework of optimal foraging theory to examine how female grey seals foraging behaviour varied with size, and across the period between moult and breeding. Larger seals undertook trips of greater duration and travelled further from haul-out sites than smaller seals. However, body fat was negatively associated with trip duration and extent. Seals spent more time at sea during the summer, but trips were shorter in extent, suggesting more localized foraging during this season.

Broad-scale multi-species declines in populations of North American sea ducks for unknown reasons is cause for management concern. Oceanic regime shifts have been associated with rapid changes in ecosystem structure of the North Pacific and Bering Sea. However, relatively little is known about potential effects of these changes in oceanic conditions on marine bird populations at broad scales. I examined changes in North American breeding populations of sea ducks from 1957 to 2011 in relation to potential oceanic regime shifts in the North Pacific in 1977, 1989, and 1998. There was strong support for population-level effects of regime shifts in 1977 and 1989, but little support for an effect of the 1998 shift. The continental-level effects of these regime shifts differed across species groups and time. Based on patterns of sea duck population dynamics associated with regime shifts, it is unclear if the mechanism of change relates to survival or reproduction. Results of this analysis support the hypothesis that population size and trends of North American sea ducks are strongly influenced by oceanic conditions. The perceived population declines appear to have halted >20 years ago, and populations have been relatively stable or increasing since that time. Given these results, we should reasonably expect dramatic changes in sea duck population status and trends with future oceanic regime shifts.

Cross-ecosystem movements of material and energy, particularly reciprocal resource fluxes across the freshwater-land interface, have received major attention. Freshwater ecosystems may receive higher amounts of subsidies (i.e., resources produced outside the focal ecosystem) than terrestrial ecosystems, potentially leading to increased secondary production in freshwaters. Here we used a meta-analytic approach to quantify the magnitude and direction of subsidy inputs across the freshwater-land interface and to determine subsequent responses in recipient animals. Terrestrial and freshwater ecosystems differed in the magnitude of subsidies they received, with aquatic ecosystems generally receiving higher subsidies than terrestrial ecosystems. Surprisingly, and despite the large discrepancy in magnitude, the contribution of these subsidies to animal carbon inferred from stable isotope composition did not differ between freshwater and terrestrial ecosystems, likely due to the differences in subsidy quality. The contribution of allochthonous subsidies was highest to primary consumers and predators, suggesting that bottom-up and top-down effects may be affected considerably by the input of allochthonous resources. Future work on subsidies will profit from a food web dynamic approach including indirect trophic interactions and propagating effects. � 2012 by the Ecological Society of America.