Ecosystem Function

In the search for an integrated understanding of the relationships among productive activities, human well-being, and ecosystem functioning, we evaluated the services delivered by a tropical dry forest (TDF) ecosystem in the Chamela Region, on the Pacific Coast of Mexico. We synthesized information gathered for the past two decades as part of a long-term ecosystem research study and included social data collected in the past four years using the Millennium Ecosystem Assessment (MA) conceptual framework as a guide. Here we identify the four nested spatial scales at which information has been obtained and emphasize one of them through a basin conceptual model. We then articulate the biophysical and socioeconomic constraints and drivers determining the delivery of ecosystem services in the Region. We describe the nine most important services, the stakeholders who benefit from those services, and their degree of awareness of such services. We characterize spatial and temporal patterns of the services' delivery as well as trade-offs among services and stakeholders. Finally, we contrast three alternative future scenarios on the delivery of ecosystem services and human well-being. Biophysical and socioeconomic features of the study site strongly influence human-ecosystem interactions, the ecosystem services delivered, the possible future trajectories of the ecosystem, and the effect on human well-being. We discuss future research approaches that will set the basis for an integrated understanding of human-ecosystem interactions and for constructing sustainable management strategies for the TDF.

Identifying potential food sources in mangrove ecosystems is complex because of the multifarious inputs from both land and sea. This study, which was conducted in the Manko mangrove ecosystem of Okinawa, Japan, determined the composition of the stable isotopes δ(13)C and δ(15)N in primary producers and macrozoobenthos to estimate the potential food sources assimilated and to elucidate the target trophic levels of the macrozoobenthos. We measured the two stable isotope signatures of three gastropods (Cerithidea sp., Cassidula mustelina, Peronia verruculata), two crabs (Grapsidae sp., Uca sp.), mangrove tree (Kandelia candel) leaves, and sediment from the mangrove ecosystem. The respective carbon and nitrogen isotope signature results were as follows: -22.4‰ and 8.6‰ for Cerithidea sp., -25.06‰ and 8‰ for C. mustelina, -22.58‰ and 8‰ for P. verruculata, -24.3‰ and 10.6‰ for unidentified Grapsidae, -21.87 ‰ and 11.5 ‰ for Uca sp., -29.81‰ and 11‰ for K. candel, and -24.23‰ and 7.2‰ for...

We summarized landscape approaches used in the study of freshwater ecosystems, updated recent literature reviews on interactions between terrestrial and lotic ecosystems, and discussed the influence of J-NABS on developments in the field. We focused primarily on studies of freshwater ecosystems done at or above the catchment scale. Special issues of J-NABS and other journals have advanced our understanding of the effects of spatially distributed characteristics and phenomena on aquatic ecosystems. Topics that have been well covered in J-NABS include use of classification to predict biotic assemblages and impacts of human disturbance (especially urbanization) on stream structure and function. Early work focused on correlative relationships between landscape variables and various biotic components of stream systems, whereas later studies addressed causal linkages between landscape and biota, including landscape effects on hydrology, habitat at various spatial scales, and ecosystem processes. At large spatial scales (i.e., catchments or regions), landscape context and heterogeneity are important predictors of compositional, structural, and functional attributes of streams and lakes. The size of the study region and catchments and the level of disturbance across the region can interfere with our ability to generalize results across studies. Geographical information systems and remote sensing technologies are important tools for understanding and quantifying these relationships, and new sophisticated tools are available for measuring landscape pattern and context. Lotic ecosystems are challenging to study because of the directional flow of water across (and beneath) the landscape. However, new spatial analysis tools can incorporate hydrologic connectivity. Limited data on surface and groundwater connections and lack of available watershed delineations make finding similar connections between lakes and wetlands and their surrounding landscapes challenging.

Results of two monitoring programs obtained in the free-flowing section of the Danube downstream of Vienna were used to evaluate the effects of river restoration designed to increase surface water inputs into side-arms. Functional descriptors like hydrochemical parameters and plankton react immediately to restored hydrological conditions and offer the opportunity to elucidate the hydrological control on organic processing as an important ecosystem function in fluvial landscapes. Two hydraulic parameters were estimated and linked to basic ecological properties. The level of hydrological connectivity was defined as the average annual duration (days per year) of upstream surface connection and can be used as a 'simple to estimate' parameter within the planning phase. Water age, an adapted measure of residence time based on more detailed information, allow description of the temporal development in side-arms. Greater hydrological connectivity leads to lower conductivity levels and increased nutrient concentrations due to the shift of the dominating source to river water. The contribution of river flow is indicated by higher suspended solid concentrations in side-arms than disconnected water bodies. The phytoplankton biomass shows the highest mean values at a duration of integration of 1 month a and decrease with increasing connectivity. The y1 relationships point to a more 'main channel like' hydrochemical situation in the side-arms, with a medium level of phytoplankton biomass and increased autochthonous carbon export. No evidence of eutrophication was found due to the shift of the side-arm from an organic matter sink to a source. On a more detailed level, water age demonstrates the temporal patterns of riverine input, the development of plankton production and the shift between hydrological and biological control of phytoplankton vs. riverine flow in a side-arm. The hydrologic parameters were useful predictors for evaluating the effects of restoration measures in river floodplain systems.

We found a dead whale (Globicephalus macrorhynchus) whose probable cause of death was an internal injury produced by a 1m-long oilfish (Ruvettus pretiosus) that had bitten the whale´s stomach from the inside. This is the first record of an oilfish in Mexican Caribbean waters.

Disturbance-mediated species loss has prompted research considering how ecosystem functions are changed when biota is impaired. However, there is still limited empirical evidence from natural environments evaluating the direct and indirect (i.e. via biota) effects of disturbance on ecosystem functioning. Oxygen deficiency is a widespread threat to coastal and estuarine communities. While the negative impacts of hypoxia on benthic communities are well known, few studies have assessed in situ how benthic communities subjected to different degrees of hypoxic stress alter their contribution to ecosystem functioning. We studied changes in sediment ecosystem function (i.e. oxygen and nutrient fluxes across the sediment water-interface) by artificially inducing hypoxia of different durations (0, 3, 7 and 48 days) in a subtidal sandy habitat. Benthic chamber incubations were used for measuring responses in sediment oxygen and nutrient fluxes. Changes in benthic species richness, structure and traits were quantified, while stress-induced behavioral changes were documented by observing bivalve reburial rates. The initial change in faunal behavior was followed by non-linear degradation in benthic parameters (abundance, biomass, bioturbation potential), gradually impairing the structural and functional composition of the benthic community. In terms of ecosystem function, the increasing duration of hypoxia altered sediment oxygen consumption and enhanced sediment effluxes of NH 4 + and dissolved Si. Although effluxes of PO 4 32 were not altered significantly, changes were observed in sediment PO 4 32 sorption capability. The duration of hypoxia (i.e. number of days of stress) explained a minor part of the changes in ecosystem function. Instead, the benthic community and disturbancedriven changes within the benthos explained a larger proportion of the variability in sediment oxygen-and nutrient fluxes. Our results emphasize that the level of stress to the benthic habitat matters, and that the link between biodiversity and ecosystem function is likely to be affected by a range of factors in complex, natural environments.

Macrophyte communities play an essential role in the way freshwater ecosystems function. It is thus of great concern to understand how environmental factors, especially anthropogenic ones, influence their composition and diversity. The aim of this study was to examine whether the effects of a herbicide mixture (50% atrazine, 35% isoproturon, 15% alachlor) on single macrophyte species can be used to predict its impact at a community level. In a first experiment we tested the sensitivity of six species (Azolla filiculoides, Ceratophyllum demersum, Elodea canadensis, Lemna minor, Myriophyllum spicatum and Vallisneria spiralis) grown separately and exposed to 0.6-600 g L -1 of the herbicide mixture. In a second experiment, conducted in microcosms, we tested the effects of herbicides on macrophyte assemblages composed of the same six species exposed to 0, 6 or 60 g L -1 of the herbicide mixture. Species grown separately exhibited growth inhibition at 60 and 600 g L -1 . At 600 g L -1 the sensitivity differed significantly between species. V. spiralis was the most resistant species, C. demersum, M. spicatum and E. canadensis exhibited intermediate sensitivities, and A. filiculoides and L. minor were the most sensitive species. In microcosms, community biomass and Shannon evenness index were reduced after 8 weeks at 60 g L -1 . Communities also exhibited changes in their composition: the relative and absolute abundance of C. demersum increased at 6 g L -1 , while the relative abundance of V. spiralis increased at 60 g L -1 . These results are in agreement with the individual responses of these species to the herbicides. It is therefore concluded that short-term effects of herbicides on simple macrophyte communities can be predicted from the sensitivity of individual species. However, further investigations are required to examine whether longer term effects can be predicted as well, especially in more complex communities.

Landscape metrics have been widely developed over the last two decades. One of the major recent developments in landscape metrics analysis was the integration of the third dimension. Topography has an extremely important role in ecosystems function and structure, even though the common analysis in landscape ecology only considers a planimetric surface, which leads to some erroneous results particularly in mountain areas. In this study we tested landscape metrics behaviour in 13 sample areas of 10,000 m 2 each in several topographical conditions of Central Alentejo, Portugal. The significance analysis of the results achieved in planimetric and three-dimensional environments is presented.

The efficiency of energy transfer through food chains [food chain efficiency (FCE)] is an important ecosystem function. It has been hypothesized that FCE across multiple trophic levels is constrained by the efficiency at which herbivores use plant energy, which depends on plant nutritional quality. Furthermore, the number of trophic levels may also constrain FCE, because herbivores are less efficient in using plant production when they are constrained by carnivores. These hypotheses have not been tested experimentally in food chains with 3 or more trophic levels. In a field experiment manipulating light, nutrients, and food-chain length, we show that FCE is constrained by algal food quality and food-chain length. FCE across 3 trophic levels (phytoplankton to carnivorous fish) was highest under low light and high nutrients, where algal quality was best as indicated by taxonomic composition and nutrient stoichiometry. In 3-level systems, FCE was constrained by the efficiency at which both herbivores and carnivores converted food into production; a strong nutrient effect on carnivore efficiency suggests a carryover effect of algal quality across 3 trophic levels. Energy transfer efficiency from algae to herbivores was also higher in 2-level systems (without carnivores) than in 3-level systems. Our results support the hypothesis that FCE is strongly constrained by light, nutrients, and food-chain length and suggest that carryover effects across multiple trophic levels are important. Because many environmental perturbations affect light, nutrients, and foodchain length, and many ecological services are mediated by FCE, it will be important to apply these findings to various ecosystem types. ecological efficiency ͉ ecological stoichiometry ͉ fish ͉ zooplankton ͉ phytoplankton

A study of pelagic and littoral species richness among microcrustaceans in 2,466 Norwegian lakes recorded 120 crustacean species: 77 cladocerans, 31 cyclopoids, and 12 calanoids, respectively. Very few species were strictly pelagic, and the pelagic crustacean zooplankton species were by far outnumbered by their littoral counterparts. More than two-thirds of the total crustacean species numbers in lakes were accounted for by species with a littoral preference. A considerable number of species occurred with low frequency, and the median total number of crustacean species in the lakes was only 14. A majority of littoral species also occurred commonly in pelagic samples, and vice versa. Some species are truly both littoral and pelagic, and nearly all species occurring in pelagic samples were also common in littoral samples. A high proportion of the common littoral species was only recorded occasionally in pelagic samples, and should thus be considered strictly littoral. There was no significant correlation between lake area and species richness for pelagic or littoral species. Our findings demonstrate the importance of including littoral species when assessing microcrustacean diversity in lakes, and we question the practice of considering species as either pelagic or littoral, because a majority of the recorded species was common in both habitats. It calls for a further discussion of the term ''planktonic'', since most of the species are at least partly ''semiplanktonic.''

Summary Biogeographical models of species’ distributions are essential tools for assessing impacts of changing environmental conditions on natural communities and ecosystems. Practitioners need more reliable predictions to integrate into conservation planning (e.g. reserve design and management). Most models still largely ignore or inappropriately take into account important features of species’ distributions, such as spatial autocorrelation, dispersal and migration, biotic and environmental interactions. Whether distributions of natural communities or ecosystems are better modelled by assembling individual species’ predictions in a bottom‐up approach or modelled as collective entities is another important issue. An international workshop was organized to address these issues. We discuss more specifically six issues in a methodological framework for generalized regression: (i) links with ecological theory; (ii) optimal use of existing data and artificially generated data; (iii) inco...

Canyon-type urban streets are one of the urban forms in which critical and harmful situations for health and the urban environment are emerging today, such as urban heat islands, areas of poor ventilation, and retention zones for pollutants emitted by road traffic, heating, and industrial activities. The higher pollution levels are due to inappropriate relationships between morphological and microclimatic parameters specific to urban street canyons. Previous studies have highlighted the most common factors, namely the aspect ratio (H/W), the orientation of the street to the prevailing winds, and vegetation. In the city of Algiers, the urban street canyon is particularly noticeable in two dominant urban fabrics: the medieval organic fabric and the colonial fabric dating back to the French occupation. This paper aims to explain the effect of different factors specific to urban canyons in Algiers on the concentration trends of air pollutants by adopting the CODASC database, which contains data on normalized average air pollutant concentrations (C+) related to different street canyon models, according to aspect ratios H/W values, wind flow direction (α), tree stand density (ρs), and tree crown porosity (PVol). In order to validate the developed methodology, measurements of particle pollution concentrations were carried out at several points on the studied streets, using an analyzer equipped with the GP2Y1010AU0F microsensor. Based on the collected data, a statistical model was developed to assist in the reconfiguration of canyon-type streets in order to increase the dispersion of pollutants and consequently, reduce their concentrations. The results showed that Larbi Ben M'Hidi Street is more polluted than Mohammed Azzouzi Street due to the impact of the maximum values of the aspect ratio and tree density on wind behavior. The study's findings could provide a strategic guide for pollution mitigation, to be used by urban planners in the design and implementation phases of sustainable urban development projects in Algiers.

AimPlant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits.LocationTundra biome.Time periodData collected between 1964 and 2016.Major taxa studied295 tundra vascular plant species.MethodsWe compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species‐level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and speci...

A fundamental goal of ecological network research is to understand how the complexity observed in nature can persist and how this affects ecosystem functioning. This is essential for us to be able to predict, and eventually mitigate, the consequences of increasing environmental perturbations such as habitat loss, climate change, and invasions of exotic species. 2. Ecological networks can be subdivided into three broad types: 'traditional' food webs, mutualistic networks and host-parasitoid networks. There is a recent trend towards cross-comparisons among network types and also to take a more mechanistic, as opposed to phenomenological, perspective. For example, analysis of network configurations, such as compartments, allows us to explore the role of co-evolution in structuring mutualistic networks and host-parasitoid networks, and of body size in food webs. Research into ecological networks has recently undergone a renaissance, leading to the production of a new catalogue of evermore complete, taxonomically resolved, and quantitative data. Novel topological patterns have been unearthed and it is increasingly evident that it is the distribution of interaction strengths and the configuration of complexity, rather than just its magnitude, that governs network stability and structure. 4. Another significant advance is the growing recognition of the importance of individual traits and behaviour: interactions, after all, occur between individuals. The new generation of high-quality networks is now enabling us to move away from describing networks based on species-averaged data and to start exploring patterns based on individuals. Such refinements will enable us to address more general ecological questions relating to foraging theory and the recent metabolic theory of ecology. 5. We conclude by suggesting a number of 'dead ends' and 'fruitful avenues' for future research into ecological networks.

A standardized methodology to assess the impacts of land-use changes on vegetation and ecosystem functioning is presented. It assumes that species traits are central to these impacts, and is designed to be applicable in different historical, climatic contexts and local settings. Preliminary results are presented to show its applicability. Eleven sites, representative of various types of land-use changes occurring in marginal agro-ecosystems across Europe and Israel, were selected. Climatic data were obtained at the site level; soil data, disturbance and nutrition indices were described at the plot level within sites. Sixteen traits describing plant stature, leaf characteristics and reproductive phase were recorded on the most abundant species of each treatment. These data were combined with species abundance to calculate trait values weighed by the abundance of species in the communities. The ecosystem properties selected were components of above-ground net primary productivity and ...

We present a multisite analysis of the relationship between plant diversity and ecosystem functioning within the European BIODEPTH network of plant-diversity manipulation experiments. We report results of the analysis of 11 variables addressing several aspects of key ecosystem processes like biomass production, resource use (space, light, and nitrogen), and decomposition, measured across three years in plots of varying plant species richness at eight different European grassland field sites. Differences among sites explained substantial and significant amounts of the variation of most of the ecosystem processes examined. However, against this background of geographic variation, all the aspects of plant diversity and composition we examined (i.e., both numbers and types of species and functional groups) produced significant, mostly positive impacts on ecosystem processes. Analyses using the additive partitioning method revealed that complementarity effects (greater net yields than predicted from monocultures due to resource partitioning, positive interactions, etc.) were stronger and more consistent than selection effects (the covariance between monoculture yield and change in yield in mixtures) caused by dominance of species with particular traits. In general, communities with a higher diversity of species and functional groups were more productive and utilized resources more completely by intercepting Manuscript

1. Although genetic differentiation among plant populations is well known, its relevance for preserving the integrity of native ecosystems has received little attention. In a series of competition experiments with Andropogon gerardii Vitman, a dominant species of the North American Tallgrass Prairie, plant performance was related to seed provenance and restoration activities. Glasshouse experiments showed plant performance to be a function of seed source. Differential target plant performance relative to competitor identity was observed when plant performance was assessed across a range of competitor densities. Local and non-local plants were larger when competing against non-local plants relative to the local and cultivar plants, while cultivar plants were consistently larger than local and non-local plants regardless of competitor identity or density. The consistency of cultivar performance could reflect directional selection during cultivar development for consistently high fecundity, vigorous vegetative growth and resistance to pathogens. 3. In a field experiment, non-local plants were half the size of local and cultivar plants, supporting recognition of seed provenances of A. gerardii based on differences in plant performance among source populations observed in the glasshouse study, and previous genetic analyses of the same populations. 4. This study establishes that seed provenance and restoration activities influence the competitive ability of a dominant species which, in turn, may affect plant community structure and potential ecosystem function.

This article will explore a repopulating approach as a means of producing archaeological and historical narratives of upland land use in the Scottish Highlands which go beyond tired notions of marginality, liminality and peripherality. These narratives, historically dominant in the study of upland landscapes, continue to have harmful impacts on the contemporary communities of these landscapes. Through the case study of Rannoch Moor, a material focus on taskscapes, movement and interactions allows for the production of narratives which highlight the past busyness of landscapes often now considered to be empty and 'wild'. In the current economic and political climate, as restoration and rewilding, often carried out at a landscape scale are increasingly incentivised in this region it is important that archaeological and historical narratives produced about such landscapes reflect their cultural dimensions as landscapes once populated and managed intensively and sustainably, and only comparatively recently cleared. This article takes an explicitly activist archaeological approach to the production of creative and embodied interpretative narratives in an attempt to present an engaging alternative to the dominant narratives of upland emptiness and wildness.

Today's questions concerning the role of soil organic matter (SOM) in soil fertility, ecosystem functioning and global change can only be addressed through knowledge of the controls on SOM stabilization and their interactions. Pyrolysis molecular beam mass spectrometry (py-MBMS) provides a powerful and rapid means of assessing the biochemical composition of SOM. However, characterization of SOM composition alone is insuYcient to predict its dynamic behavior. Chemical fractionation is frequently used to isolate more homogeneous SOM components, but the composition of fractions is frequently unknown. We characterized biochemical SOM composition in two previously studied soils from the USA, under contrasting land uses: cultivated agriculture and native vegetation. Bulk soils, as well as chemically isolated SOM fractions (humic acid, humin and non-acid hydrolysable), were analyzed using py-MBMS. Principal components analysis (PCA) showed distinct diVerences in the SOM composition of isolated fractions. Py-MBMS spectra and PCA loadings were dominated by low molecular weight fragments associated with peptides and other N-containing compounds. The py-MBMS spectra were similar for native whole-soil samples under diVerent vegetation, while cultivation increased heterogeneity. An approach based on previously published data on marker signals also suggests the importance of peptides in distinguishing samples. While the approach described here represents signiWcant progress in the characterization of changing SOM composition, a truly quantitative analysis will only be achieved using multiple internal standards and by correcting for inorganic interference during py-MBMS analysis. Overall, we have provided proof of principle that py-MBMS can be a powerful tool to understand the controls on SOM dynamics, and further method development is underway.

Urban forests provide important ecosystem services, such as urban air quality improvement by removing pollutants. While robust evidence exists that plant physiology, abundance, and distribution within cities are basic parameters affecting the magnitude and efficiency of air pollution removal, little is known about effects of plant diversity on the stability of this ecosystem service. Here, by means of a spatial analysis integrating system dynamic modeling and geostatistics, we assessed the effects of tree diversity on the removal of tropospheric ozone (O3) in Rome, Italy, in two years (2003 and 2004) that were very different for climatic conditions and ozone levels. Different tree functional groups showed complementary uptake patterns, related to tree physiology and phenology, maintaining a stable community function across different climatic conditions. Our results, although depending on the city‐specific conditions of the studied area, suggest a higher function stability at increas...

Termite mounds, though more often than not neglected, are one of the most ideal naturally occurring biofertilizers, found throughout the tropics. Although termites are damaging in nature, their termitaria is a storehouse of packed nutrients and beneficial microorganisms. Its physico-chemical and biological characteristics surpass those of the surrounding soil. Additionally, they are also helpful in soil nutrient cycling and are excellent ecosystem engineers. This article emphasizes on various studies conducted by workers to analyze its properties and its impact on crop growth. Due to its eco-friendly and sustainable nature, it will assist in reducing production costs and hence is a viable option to be used in farming practices.

There are probably millions of species in the microorganismal domains Bacteria and Archaea (the prokaryotes), and we are only just beginning to work out the basic principles governing their distribution and abundance in natural environments. One characteristic that has become clear is that prokaryote diversity in aquatic environments is orders of magnitude less than in sediments and soils. Hypotheses and models explaining such differences are under development and are beginning to offer promising insights into the mechanisms governing prokaryote diversity and ecosystem function.

Sustainable forest management integrates ecological, social, and economic objectives. To achieve the former, researchers and practitioners are modifying silvicultural practices based on concepts from successional and landscape ecology to provide a broader array of ecosystem functions than is associated with conventional approaches. One such innovation is disturbance-based management. Under this approach, forest practices that emulate natural ecological processes, such as local disturbance regimes, are viewed as more likely to perpetuate the evolutionary environment and ecosystem functions of the forest matrix. We examine how this concept has been applied in three U.S. forest types: Pacific Northwest temperate coniferous, Western mixed-conifer, and Northeastern northern hardwood forests. In general, stand-level treatments have been widely used and often closely mimic historic disturbance because forest structure and composition guidelines have been well defined from reconstructive research. Disturbance-based landscape management, however, has not yet been closely approximated in the three forest types we examined. Landscape implementation has been constrained by economic, ownership, safety, and practical limitations. Given these constraints we suggest that disturbancebased management concepts are best applied as an assessment tool with variable implementation potential. Silviculture practices can be compared against the frequency, scale, and level of biological legacies characteristic of natural disturbance regimes to evaluate their potential impact on ecosystem sustainability. Recent landscape ecology texts and some U.S. regional management plans ) have proposed using natural disturbance as a model for sustainable forest management. This chapter examines how forest managers can use natural disturbance patterns and

The EcApRHA project (Applying an Ecosystem Approach to (sub) Regional Habitat Assessment) aims to address gaps in the development of biodiversity indicators for the OSPAR Regions. In particular, the project aims to overcome challenges in the development of indicators relating to the MSFD (Marine Strategy Framework Directive 56/2008/EU), such as Descriptor D1 (Biodiversity), D4 (Food webs) and D6 (Seafloor integrity), and to deliver an action plan to OSPAR that will enable monitoring and assessment at the (sub) regional scale, to contribute to OSPAR Intermediate Assessment 2017. Indicators related to the benthic and pelagic habitats, as well as food webs, are investigated within the project at different levels (from data to indicator; from indicator to habitat assessment; from habitat to ecosystem assessment). This report was produced as a result of the EcApRHA (Addressing gaps in biodiversity indicator development for the OSPAR Region from data to ecosystem assessment: Applying an ecosystem approach to (sub) regional habitat assessments) project. The project was co-financed by the European Union (EU). Grant No. 11.0661/2015/712630/SUB/ENVC.2 OSPAR This deliverable reflects only the author's view. The European Commission is not responsible for any use that may be made of the information it contains. What is EcApRHA? The EcApRHA project (Applying an Ecosystem Approach to (sub) Regional Habitat Assessment) aims to address gaps in the development of biodiversity indicators for the OSPAR Regions. In particular, the project aims to overcome challenges in the development of indicators relating to the MSFD (Marine Strategy Framework Directive 56/2008/EU), such as Descriptor D1 (Biodiversity), D4 (Food webs) and D6 (Seafloor integrity), and to deliver an action plan to OSPAR that will enable monitoring and assessment at the (sub) regional scale, to contribute to OSPAR Intermediate Assessment 2017. Indicators related to the benthic and pelagic habitats, as well as food webs, are investigated within the project at different levels (from data to indicator; from indicator to habitat assessment; from habitat to ecosystem assessment). This report was produced as a result of the EcApRHA (Addressing gaps in biodiversity indicator development for the OSPAR Region from data to ecosystem assessment: Applying an ecosystem approach to (sub) regional habitat assessments) project. The project was co-financed by the European Union (EU). Grant No. 11.0661/2015/712630/SUB/ENVC.2 OSPAR This report reflects only the author's view. The European Commission is not responsible for any use that may be made of the information it contains.

The Marine Strategy Framework Directive (MSFD) requires that European Union Member States achieve "Good Environmental Status" (GES) in respect of 11 Descriptors of the marine environment by 2020. Of those, Descriptor 4, which focuses on marine food webs, is perhaps the most challenging to implement since the identification of simple indicators able to assess the health of highly dynamic and complex interactions is difficult. Here, we present the proposed food web criteria/indicators and analyse their theoretical background and applicability in order to highlight both the current knowledge gaps and the difficulties associated with the assessment of GES. We conclude that the existing suite of indicators gives variable focus to the three important food web properties: structure, functioning and dynamics, and more emphasis should be given to the latter two and the general principles that relate these three properties. The development of food web indicators should be directed towards more integrative and process-based indicators with an emphasis on their responsiveness to multiple anthropogenic pressures.

AimPlant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits.LocationTundra biome.Time periodData collected between 1964 and 2016.Major taxa studied295 tundra vascular plant species.MethodsWe compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species‐level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and speci...

Th e Cerrado is the largest savanna of South America and its physiognomy varies from savanna to woodlands. Th ere are two main types of woodlands in the Cerrado: dystrophic woodlands, dominated by N-fi xing leguminous trees (LEG), and mesotrophic woodlands dominated by non-leguminous drought-tolerant trees (DRY), which are calcicoles and sensitive to Al 3+ . Th e working hypothesis is that LEG and DRY are functional antagonists in terms of the acidifi cation/alkalization processes involving diff erent forms of inorganic nitrogen and pH, Ca 2+ and Al 3+ in soil. Tree species basal area and soil properties were used to investigate the antagonism between LEG and DRY using generalized linear models. Th e results suggest that LEG and DRY are antagonists. Th e LEG were positively associated with Al 3+ , NO 3-and NH 4+ content and negatively related to increasing Ca 2+ content, whereas the DRY were negatively associated with Al 3+ , NO 3-and NH 4+ and positively associated with increasing Ca 2+ content. Th e upper soil layer in plots dominated by LEG species became more acidic and the upper soil layer in plots dominated by DRY species became more alkaline. Th e results suggest that LEG and DRY are functional antagonists and their preferences for NH 4+ or NO 3-might infl uence the way the Cerrado woodland changes.

This study reports on a trial of methods to overcome barriers to restoration of degraded Cumberland Plain woodland. Soil scalping was compared with fire or slashing to remove existing canopy. Fire and slashing were combined with soil carbon addition at two levels, to reduce soil nitrate. Native seed was added to overcome a lack of native propagules. Treatments, applied to 2 × 2 m plots, consisted of a control; scalped; fire and slash treatments without carbon addition; fire and slash treatments at the low and the high carbon addition levels; and a further fire and a slash treatment at the low carbon level with no native seed added, to give 10 treatments in total. Scalping eliminated the existing canopy and reduced weed seed and bud banks allowing native species (and some colonising exotics) to establish by 33 months. Rapid re-growth in the fire treatment resulted in plant canopy abundance returning to control levels by 12 months, and native species richness on burnt plots remained s...

We annually monitored the abundance and size structure of herbivorous sea urchin populations (Paracentrotus lividus and Arbacia lixula) inside and outside a marine reserve in the Northwestern Mediterranean on two distinct habitats (boulders and vertical walls) over a period of 20 years, with the aim of analyzing changes at different temporal scales in relation to biotic and abiotic drivers. P. lividus exhibited significant variability in density over time on boulder bottoms but not on vertical walls, and temporal trends were not significantly different between the protection levels. Differences in densities were caused primarily by variance in recruitment, which was less pronounced inside the MPA and was correlated with adult density, indicating density-dependent recruitment under high predation pressure, as well as some positive feedback mechanisms that may facilitate higher urchin abundances despite higher predator abundance. Populations within the reserve were less variable in abundance and did not exhibit the hyper-abundances observed outside the reserve, suggesting that predation effects maybe more subtle than simply lowering the numbers of urchins in reserves. A. lixula densities were an order of magnitude lower than P. lividus densities and varied within sites and over time on boulder bottoms but did not differ between protection levels. In December 2008, an exceptionally violent storm reduced sea urchin densities drastically (by 50% to 80%) on boulder substrates, resulting in the lowest values observed over the entire study period, which remained at that level for at least two years (up to the present). Our results also showed great variability in the biological and physical processes acting at different temporal scales. This study highlights the need for appropriate temporal scales for studies to fully understand ecosystem functioning, the concepts of which are fundamental to successful conservation and management.

Difficulties in scaling up theoretical and experimental results have raised controversy over the consequences of biodiversity loss for the functioning of natural ecosystems. Using a global survey of reef fish assemblages, we show that in contrast to previous theoretical and experimental studies, ecosystem functioning (as measured by standing biomass) scales in a nonsaturating manner with biodiversity (as measured by species and functional richness) in this ecosystem. Our field study also shows a significant and negative interaction between human population density and biodiversity on ecosystem functioning (i.e., for the same human density there were larger reductions in standing biomass at more diverse reefs). Human effects were found to be related to fishing, coastal development, and land use stressors, and currently affect over 75% of the world's coral reefs. Our results indicate that the consequences of biodiversity loss in coral reefs have been considerably underestimated based on existing knowledge and that reef fish assemblages, particularly the most diverse, are greatly vulnerable to the expansion and intensity of anthropogenic stressors in coastal areas.

Monotonic, hump-shaped and zero-correlation productivity-diversity relationships have been found to date in many ecosystems. This diversity of responses has puzzled ecologists in their search for general principles on ecosystem functioning. Some state that the scale of observation is crucial in defining this relationship. We have developed a spatial model of tallgrass prairies where biomass and litter dynamics are defined by uncoupled difference equations. In this system, we periodically apply prescribed fire as a disturbance that propagates through neighboring cells. The model shows percolation thresholds at points where small-scale spatial heterogeneity and large-scale, global correlation coexist, resulting in power-law distributions in available areas for non-dominant species. These points maximize the biomass-diversity relationship. Our results suggest that spatial dependencies and the disturbance heterogeneity hypothesis are the cornerstone processes accounting for unimodality in productivity-diversity relationships.

Complex combinations of historical and local-regional processes determine the assembly of ecological communities. We investigated such processes in the Hawaiian introduced avifauna, comprising 140 years of historical records of invasions and extinctions of birds. Here the particular introduction regime (i.e., colonization attempts and number of introduced species) and priority effects constitute the historical (and regional) component, and competition is the local component. These processes are theoretically supported by means of a Lotka-Volterra model of species competition, finding that changes in the specific introduction regime might result in different extinction dynamics. Both field data and model outcomes support the biotic resistance hypothesis, so that the invasibility of new incomers decrease with species richness. Finally, we found that the resistance to new invaders depends on the particular introduction regime. Thus, community assembly models built to predict the success of exotic species should consider more scenarios than random introduction regimes.

This review addresses the significance and the mechanisms of mineral weathering by mycorrhizal fungi, and the role of this process in plant nutrition and protection from metal toxicity. The fact that mycorrhizal mycelia may actively release nutrients from mineral particles through weathering is raising an increasing interest and the uptake of mineral-derived nutrients by the host plants has been reported. Both chemical dissolution (protonation, chelation) and physical mechanisms (high hyphal pressures) are involved in the weathering process. Mineral solubilization can result in the release of the associated toxic metals. Organic acid exudation and metal complexation may represent a host plant protection mechanism.

Genetic variation in dominant species can affect plant and ecosystem functions in natural systems through multiple pathways. Our study focuses on how genetic variation in a dominant riparian tree (Populus fremontii, P. angustifolia and their natural F 1 and backcross hybrids) affects whole-tree water use, and its potential ecosystem implications. Three major patterns were found. First, in a 12-year-old common garden with trees of known genetic makeup, hybrids had elevated daily integrated leaf-specific transpiration (E tl ; P=0.013) and average canopy conductance (G c ; P=0.037), with both E tl and G c ~30% higher in hybrid cross types than parental types. Second, δ 13 C values of leaves from these same trees were significantly more negative in hybrids (P=0.004), and backcross hybrids had significantly more negative values than all other F 1 hybrid and parental types (P <0.001). Third, in the wild, a similar pattern was found in leaf δ 13 C values where both hybrid cross types had the lowest values (P <0.001) and backcross hybrids had lower δ 13 C values than any other tree type (P <0.001). Our findings have two important implications: (1) the existence of a consistent genetic difference in whole-tree physiology suggests that whole-tree gas and water exchange could be another pathway through which genes could affect ecosystems; and (2) such studies are important because they seek to quantify the genetic variation that exists in basic physiological processes-such knowledge could ultimately place ecosystem studies within a genetic framework.

Fundamental links between genes and ecosystem processes have remained elusive, although they have the potential to place ecosystem sciences within a genetic and evolutionary framework. Utilizing common gardens with cottonwood trees of known genotype, we found that the concentration of condensed tannins is genetically based and is the best predictor of ecosystem‐level processes. Condensed tannin inputs from foliage explained 55–65% of the variation in soil net nitrogen (N) mineralization under both field and laboratory conditions. Alternative associations with litter lignin, soil moisture or soil temperature were relatively poor predictors of litter decomposition and net N mineralization. In contrast to the paradigm that the effects of genes are too diffuse to be important at the ecosystem‐level, here we show that plant genes had strong, immediate effects on ecosystem function via a tight coupling of plant polyphenols to rates of nitrogen cycling.

The Southern Ocean is a major sink of anthropogenic CO2 and an important foraging area for top trophic level consumers. However, iron limitation sets an upper limit to primary productivity. Here we report on a considerably dense late summer phytoplankton bloom spanning 9000 km2 in the open ocean of the eastern Weddell Gyre. Over its 2.5 months duration, the bloom accumulated up to 20 g C m−2 of organic matter, which is unusually high for Southern Ocean open waters. We show that, over 1997–2019, this open ocean bloom was likely driven by anomalies in easterly winds that push sea ice southwards and favor the upwelling of Warm Deep Water enriched in hydrothermal iron and, possibly, other iron sources. This recurring open ocean bloom likely facilitates enhanced carbon export and sustains high standing stocks of Antarctic krill, supporting feeding hot spots for marine birds and baleen whales.

Leaf chemistry alterations due to increasing atmospheric CO2 will reflect plant physiological changes and impact ecosystem function. Longleaf pine was grown for 20 months at two levels of atmospheric CO2 (720 and 365 µmol mol -1 ), two levels of soil N (4 g m -2 year -1 and 40 g m -2 year -1 ), and two soil moisture levels (-0.5 and -1.5 MPa) in open top chambers. After 20 months of exposure, needles were collected and ergastic substances including starch grains and polyphenols were assessed using light microscopy, and calcium oxalate crystals were assessed using light microscopy, scanning electron micros copy, and transmission electron microscopy. Polyphenol content was also determined using the Folin-Denis assay and condensed tannins were estimated by precipitation with protein. Evaluation of phenolic content histochemically was compared to results obtained using the Folin-Denis assay. Total leaf polyphenol and condensed tannin content were increased by main effects of elevated CO2, low soil N and well-watered conditions. Elevated CO2 and low soil N decreased crystal deposition within needle phloem. Ele vated CO2 had no effect on the percentage of cells within the mesophyll, endodermis, or transfusion tissue which contained visible starch inclusions. With respect to starch accumulation in response to N stress, mesophyll > en dodermis > transfusion tissue. The opposite was true in the case of starch accumulation in response to main effects of water stress: mesophyll < endodermis < transfusion tissue. These results indicate that N and water conditions significantly affect deposition of leaf ergastic substances in

Human impacts, including global change, may alter the composition of soil faunal communities, but consequences for ecosystem functioning are poorly understood. We constructed model grassland systems in the Ecotron controlled environment facility and manipulated soil community composition through assemblages of different animal body sizes. Plant community composition, microbial and root biomass, decomposition rate, and mycorrhizal colonization were all markedly affected. However, two key ecosystem processes, aboveground net primary productivity and net ecosystem productivity, were surprisingly resistant to these changes. We hypothesize that positive and negative faunal-mediated effects in soil communities cancel each other out, causing no net ecosystem effects.

Elevated nitrogen (N) inputs into terrestrial ecosystems are causing major changes to the composition and functioning of ecosystems. Understanding these changes is challenging because there are complex interactions between ÔdirectÕ effects of N on plant physiology and soil biogeochemistry, and ÔindirectÕ effects caused by changes in plant species composition. By planting high N and low N plant community compositions into high and low N deposition model terrestrial ecosystems we experimentally decoupled direct and indirect effects and quantified their contribution to changes in carbon, N and water cycling. Our results show that direct effects on plant growth dominate ecosystem response to N deposition, although long-term carbon storage is reduced under high N plant-species composition. These findings suggest that direct effects of N deposition on ecosystem function could be relatively strong in comparison with the indirect effects of plant community change.

As of 2013 in Mexico, the creation, support and development of the LGBT tourist segment were established into the Mexican federal government policies, which has not been consolidated besides lacking of statistical and economic data so its socioeconomic impact is known. The objective of this research is to reflect on the social and economic effect generated by an LGBT friendly tourist destination resulting from the touristic practices that take place in Puerto Vallarta, Jalisco. This beach destination is considered the most important LGBT tourist destination in the country due to the amount of economic income it generates and the touristic infrastructure that has been developed. Some considerations are made on the relationship between the expenditure generated by tourists and the income received by residents, as well as its socio-environmental impact. The methodology used is of a mixed nature, emphasizing the integration of economic data in a quantitative way besides ethnography carried out in the destination in a qualitative way. The results of this social phenomenon called LGBT Tourism finally unleashed a synergy and power relations between the different actors involved in Puerto Vallarta: government, businessmen, civil associations, residents and to a lesser extent tourist.

The global decline of eel populations due to habitat fragmentation, pollution, parasites, and overexploitation has driven existing management efforts. However, assessing the conservation value of fish within local aquatic ecosystems is essential for informed policy support and requires further evaluation. This study evaluated conservation values in local ecosystems by examining fish diversity, migratory patterns, endemism, and the International Union for Conservation of Nature (IUCN) status. Eels and sympatric fish were monitored in the Athi and Ramisi Rivers from April 2021 to May 2022 using glass and double fyke nets. Fish diversity and occurrence data, combined with Likert-scored data on migration, IUCN status, endemism, and ecological importance, were analyzed and compared using one-way ANOVA. Results indicated significantly higher fish diversity (df = 2856, t = 22, p < 0.05) in Ramisi (0.16 ± 0.003) compared to Athi (0.09 ± 0.001), with downstream sites harboring significantly higher diversity (F = 205, p < 0.05). Among eels, Anguilla mossambica (0.67 ± 0.003), Anguilla bengalensis, and Anguilla bicolor (0.631 ± 0.001) exhibited the highest conservation ranks due to their elevated IUCN status and migratory behavior compared to sympatric fish species. Ramisi had a notably higher conservation score (0.46 ± 0.002) than Athi (0.42 ± 0.001) (df = 2473, t = 17, p < 0.05). The study highlights the importance of composite metrics, incorporating endemism, migration, and IUCN status over individual species data, advancing the understanding of Kenyan river conservation and contributing to global aquatic habitat management.

Summary1. Harvest‐related poisoning events are common in tropical streams, yet research on stream recovery has largely been limited to temperate streams and generally does not include any measures of ecosystem function, such as leaf breakdown.2. We assessed recovery of a second‐order, high‐gradient stream draining the Luquillo Experimental Forest, Puerto Rico, 3 months after a chlorine‐bleach poisoning event. The illegal poisoning of freshwater shrimps for harvest caused massive mortality of shrimps and dramatic changes in those ecosystem properties influenced by shrimps. We determined recovery potential using an established recovery index and assessed actual recovery by examining whether the poisoned reach returned to conditions resembling an undisturbed upstream reference reach.3. Recovery potential was excellent (score = 729 of a possible 729) and can be attributed to nearby sources of organisms for colonisation, the mobility of dominant organisms, unimpaired habitat, rapid flush...

Male Scarlet Ibises ( Eudocimus ruber ) and White Ibises ( Eudocimus albus ) have bills that are on average 22% longer than females, yet only half of this difference can be attributed to body-size differences. In this work it is suggested that the sexual dimorphism in bill length and bill shape is based in large part upon the role of bill length in determining the outcome of male bill-sparring contests. Sexual differences in bill morphology and behavior were investigated in a captive flock of 350 Scarlet Ibises. In 29 instances of males sparring with males in contests prior to breeding and in 11 instances of nest take-over during breeding, no significant differences in age, body size, or body condition between winning and losing males were found. However, males winning bill-sparring contests and nest take-overs had significantly longer bills than losing males. Longer billed males also bred significantly earlier than shorter billed males in captivity. Sexual differences in the relationship between bill curvature, bill chord and bill length suggest that male Scarlet and White Ibises are under selection for increased bill length. In addition, among 16 of 23 ibis species for which information was available, sexual dimorphism in bill length was positively associated with colonial nesting but was not associated with group foraging. This result supports the theory that close proximity during nesting is one feature that may facilitate bill sparring between males, resulting in selection for longer bills.

The Black Woodpecker (Dryocopus martius L.) is both an ecosystem engineer and an umbrella species: it has the capacity to modify its environment through cavity excavation, which in turn favors a large range of species that depend on cavities but are unable to dig them themselves (secondary cavity nesters). However, the factors driving cavity excavation by the Black woodpecker at the tree scale remain poorly known. We analyzed the characteristics of trees bearing Black Woodpecker cavities to assess the bird's local habitat requirements and their conservation potential as habitat trees. We compared the traits and characteristics of trees bearing Black Woodpecker cavities (n = 60) and control trees (n = 56) in two managed lowland broadleave-dominated forests in France. We hypothesized that: (i) Cavity-trees would have lower wood density and display more conks of fungi than control-trees; (ii) The local environment of cavity-trees would be less crowded than those of the control trees. In particular, the first branch would be higher up, and their first neighboring tree would be further away from cavity-trees compared to control-trees; (iii) Cavity-trees would display a higher number of other woodpecker cavities and more saproxylic microhabitats than the control-trees. We validated most of our hypotheses and showed that cavity trees differed significantly from their control counterparts. Black Woodpeckers excavate trees with softer wood and higher first branches in a less crowded environment, thus minimizing both the energy dedicated to cavity excavation and predation risk. Second, cavitytrees bear more microhabitats and play a complementary umbrella role than what was documented before. They also appear a good candidate for habitat-tree conservation. In terms of biodiversity-friendly management measures, it would be beneficial to favor large isolated standing trees devoid of low branches (notably beech), especially in stands dominated by other tree species.

Abstract: The Louisiana red swamp crayfish is a pest species in California, unwanted because it is elbowing out native crayfish, snails, salamanders and frogs. Think of it as the Viking of the crayfish world–hearty, strong and aggressive, especially on foreign soil.

Difficulties in scaling up theoretical and experimental results have raised controversy over the consequences of biodiversity loss for the functioning of natural ecosystems. Using a global survey of reef fish assemblages, we show that in contrast to previous theoretical and experimental studies, ecosystem functioning (as measured by standing biomass) scales in a nonsaturating manner with biodiversity (as measured by species and functional richness) in this ecosystem. Our field study also shows a significant and negative interaction between human population density and biodiversity on ecosystem functioning (i.e., for the same human density there were larger reductions in standing biomass at more diverse reefs). Human effects were found to be related to fishing, coastal development, and land use stressors, and currently affect over 75% of the world's coral reefs. Our results indicate that the consequences of biodiversity loss in coral reefs have been considerably underestimated based on existing knowledge and that reef fish assemblages, particularly the most diverse, are greatly vulnerable to the expansion and intensity of anthropogenic stressors in coastal areas.

In response to the ongoing decline of fauna worldwide, there has been growing interest in the rewilding of whole ecosystems outside of fenced sanctuaries or offshore islands. This interest will inevitably result in attempts to restore species where eliminating threats from predators and competitors is extremely challenging or impossible, or reintroductions of predators that will increase predation risk for extant prey (i.e., coexistence conservation). We propose ‘Mini Safe Havens’ (MSHs) as a potential tool for managing these threats. Mini Safe Havens are refuges that are permanently permeable to the focal species; allowing the emigration of individuals while maintaining gene flow through the boundary. Crucial to the effectiveness of the approach is the ongoing maintenance and monitoring required to preserve a low-to-zero risk of key threats within the MSH; facilitating in-situ learning and adaptation by focal species to these threats, at a rate and intensity of exposure determined ...