Biodiversity and ecosystem functions and services State of knowledge Marine ecosystems play a key role in ecological and biogeochemical processes at a global scale and the economic value of marine ecosystem services is estimated to exceed even the most conspicuous terrestrial systems, including tropical rain forests (Costanza et al 1997). Although many excellent examples demonstrate how single species loss or overexploitation of marine resources compromises important services and functions (e.g. fisheries collapse, shoreline erosion, dead zones), the specific roles of species and assemblage in the delivery of ecosystem functions and services remains largely unknown for marine systems. All biodiversity, from viruses and bacteria to whales, are potentially important. For example, synergistic interactions among bacterial species and bacterial composition can determine rates of nutrient recycling, a key aspect of ecosystem functioning. Simultaneously, whale feeding could influence nutrient recycling through cascading top-down effects through different trophic levels. Little is also known about how specific biodiversity loss relates to marine ecosystem functioning and services, particularly in poorly studied coastal areas in developing countries, and deep-sea and polar regions. Marine scientists have therefore developed a new focus trying to understand biodiversity and ecosystem functioning and services relationships, and therefore, ultimately, to human health and wellbeing. The goal of this new research mainstream is to predict “which”, “when”, and “where” biodiversity losses, from genes to species, to habitats and ecosystems, ultimately compromise ocean functions and services. Recognizing the link between ocean life and health of all life on Earth, scientists are banding together to address urgent questions on connections between biodiversity and ecosystem functions and services in the context of changing oceans. Catastrophic and episodic events that span from natural and uncontrollable events to specific human activities (including earthquakes and tsunamis, landslides, blooms of algae and jellyfish) alter ecosystem functions and services over large spatial and temporal scales. Understanding the relative contributions of these events offers the potential of minimizing some impacts, and a great capacity to describe potential consequences of those we cannot change. The need to understand relationships between biodiversity and ecosystem functioning has become increasingly evident in the last two decades. Early small-scale, manipulative experiments generally reported positive relationships between biodiversity and ecosystem functioning (Kinzig et al. 2001; Loreau et al. 2001; Hooper et al. 2005), but also idiosyncratic relationships (Emmerson et al. 2001). Analysis of several ecosystems, including seagrass beds and rocky intertidal shore indicated that functional traits and variations in species functional roles can be more important than species richness per se (O’Connor and Crowe et al. 2005). Diversity-functioning relationships can also change depending on trophic positions and circumstances; for example, changes in primary producers and their interactions can modify ecosystem functioning (Duffy et al 2007). Moreover, recent reports of exponential increases in ecosystem functioning with increasing biodiversity in deep-sea (Danovaro et al 2008) and in tropical ecosystems (Mora et al. 2011) challenge previous theoretical assumptions (Loreau et al. 2008). These results show exponential increase in ecosystem efficiency with increased functional biodiversity. The similarity of these relationships across a wide range of ecosystems suggests mutually positive functional interactions (ecological facilitation) may characterize some of the most widespread biomes on Earth. The theoretical implications of these findings are important because non-saturating relationships indicates 1 that biodiversity loss might cause exponential and potentially irreversible declines in functions and services over broad geographic areas. Few studies address the numbers of species and individuals necessary to maintain different ecosystem goods and services, but evidence suggests that abundant and rare species can help to preserve ecosystem functions. Moreover, because delivery of many ecosystem services provided to humans occurs at a local scale, efforts to preserve these services must focus on conserving or restoring biotic integrity, rather than on simply increasing the number of species present. Indeed, evidence to date clearly demonstrates the importance of species identity and not just species number. Alteration of local food-web diversity through indirect interactions and trophic cascades provide some of the most dramatic examples of effects of biodiversity changes on ecosystem services. Intentional or accidental additions of species to marine ecosystems, either as primary producers, herbivores, carnivores or pathogens, provide some of the best examples of cascade effects of biodiversity alteration on the functioning of marine ecosystems (e.g. Ruesink et al. 2006). The Census of Marine Life provided the first global marine biodiversity database as biodiversity change, which we can now use to understand the consequences of biodiversity change (species loss, invasion, speciation and migration) for ecosystem services and thus for human societies. By utilizing the methodologies and international collaborations developed during the CoML, and identifying strategic geographic locations and habitats for long-term analysis and new studies, we can assess the consequence of changing biodiversity, either as changes in species richness of species identify, for the functioning of marine ecosystems, and thus develop a more comprehensive understanding of ecosystem services of the world ocean. Valuing ecosystem services requires studies on human resource use of marine biodiversity because the impact on marine species differs among regions, reflecting variation in human socio-economic conditions and local cultures. The global network of scientists and local communities, established by the CoML, forms the basis for a further important step forward in the understanding of the crucial importance of marine biodiversity for human beings globally. Sustainable ocean use requires a solid understanding of the interactions between biodiversity, ecosystem functions and services and their response to global and local drivers. Human-induced changes will affect resource use patterns, with major social and economic consequences (Chapin et al. 2000). Through new research linking biodiversity and ecosystem functions and services, we hope to minimize and potentially reverse declines in ocean and human health, and increase ocean sustainability. These objectives require rigorous scientific evaluation of functions and services within different marine habitats and ecosystems to provide baselines for wise ocean management. Increased knowledge can advance sustainable ocean use by: Identifying generalities and specificity of biodiversity-ecosystem functioning and ecosystem services relationships, which will improve valuation of marine biodiversity. Basic quantitative data for climate adaptation programs (such as estimation of carbon sequestration in contrasting marine ecosystems) can advise carbon offset and related socio-economic activities Providing knowledge on spatio-temporal variation in marine ecosystem services that will bridge natural science and social science research, and promote interdisciplinary 2 research to advise marine conservation strategies such Marine Protected Area design and planning wise use of marine environments. Proposed research 1) Objectives of research Our primary objective is to understand how the wealth of marine biodiversity contributes to marine ecosystem functions and how these functions, in turn, add to the ecosystem services on which humans depend. This objective requires that we: i) elucidate global patterns in ecosystem functioning and services that marine organisms provide, and how they vary among ecosystems; Ii) clarify generality and specificity in relationships between biodiversity and ecosystem functioning and services; and iii) produce scenarios on how these relationships might be modified by global climate change and other drivers. To achieve these objectives, we will integrate interdisciplinary approaches that combine manipulative experiments and field observations (with new technologies and methods) that include remote sensing, GIS, and molecular genetic approaches, as well as socio-economic studies on human resource use in collaboration with Theme Understanding Change. Collaboration between traditional taxonomists and molecular approaches will form a key element of observational and sampling-based approaches, fostering collaboration with Themes Current Baselines and Understanding Change. 2) Major questions to be addressed We will investigate how marine biodiversity (genetic, species, habitat, and ecosystems) relates to major functions of marine ecosystems that provide a variety of services for human well-being. The key questions form four main groups: 1. Variability: How does the relationship between biodiversity and ecosystem functioning change across different habitats at a global scale? What is the specific functional value of contrasting habitat types in world’s ocean? Are biodiversity hot spots such as coral reefs also hot-spots of ecosystem services? 2. Interactions: How is biodiversity linked to ecosystem services? What is the functional role of rare species? How do small and large species (from viruses to whales) interact in delivery of services? How do species interactions across ecosystems (from the shallow ocean to the deep) contribute to the functioning of each other? How do changes in species function change through their life cycles? Are ecosystem functions and services correlated? How do changes in function influence the production of goods and services? Are there always trade-offs between provisioning (e.g., fish production) and regulating (e.g. nutrient recycling) functions and services? 3. Vulnerability: How can we effectively monitor loss of functions or services in marine ecosystems to understand how far we can erode standing stocks of a species before collapsing the functions they provide? Where are the “tipping points” in the link between biodiversity and ecosystem functioning in marine ecosystems? Which aspects of ecosystem functions and services are most vulnerable to collapse, and which can be restored (and how) when lost? How will climate change impact different marine ecosystem services and how do these impacts vary among habitats? 4. Socio-economic implications: What is the global (economic and intangible) value of various habitats from the intertidal to the deep sea and to what extent does this 3 value depend on biodiversity? How does regional variation in culture and resource use affect the relationship between ecosystem function and services? Methods 1) Strategies To test the key interdisciplinary questions on the interactions between biodiversity, ecosystem functions and services, we envisage a novel, integrated, and advanced approach that embraces the wide range of cutting edge methods emerging in physical oceanography, biogeochemistry (e.g., stable isotope analyses), and ocean observation. We will combine classic sampling and manipulative experiments with modern molecular and ocean observation strategies to test relationships between biodiversity (genetic, species richness and evenness, habitat diversity) and key regulatory and provisional functions and services. In parallel with these new data initiatives, we believe the ecological questions have matured to the point that meta-analysis, modeling, and real world analysis. Through parallel efforts of small-scale manipulative experiments and meta-analyses, we believe it is possible to extend the spatial and temporal scales of observation to a biodiversity dimension that actually reflects the real world rather than a small subset of it. As part of this initiative, we envisage the development of parallel studies in different habitats across the world and in the same habitats in different geographic regions, covering a wide range of spatial scales from local to global. We will also embrace novel statistical approaches and modeling tools to enhance data interpretation. Finally, socio-economic analysis will be needed to define better the implications of different anthropogenic impacts and the effects of biodiversity conservation strategies on the preservation of ecosystem goods and services. This last objective in particular can be achieved only through strong integration across all of the LICO themes. (a) To investigate how ecosystem services link to biodiversity, rare species, and different life history stages, we will undertake comparatively large-scale manipulative experiments with diverse assemblages. Although diverse assemblages create an unrealistic number of species permutations, we will use the same sorts of strategies used in food web studies to simplify comparisons by identifying strong, representative candidates (e.g. representative functional groups such as feeding types) as a “first pass” strategy. To enhance our knowledge of these interactions, we will try to expand experiments beyond the small containers used in most experiments to date, and expand to encompass broader spatial scales. Within LICO we will undertake comparative experiments in different regions of the world, expanding the applicability of the results to a greater range of real world situations. Specifically, we will undertake meta-analyses on data collected across different marine habitats and biomes to enhance our understanding of differences and commonalities of relationships across different habitats/ecosystems/ biomes, and to identify the drivers responsible for observed differences (if any) (e.g., Wahl et al. 2011). Recent statistical tools such as Sequential Equation Modeling and Hierarchical Bayesian Modeling offer great promise in elucidating causal relationships among environment-biodiversity-ecosystem functioning variables, and will enhance quantitative comparison across large spatial scales, which are limited in more traditional analytical approaches. (b) To understand how small and large species (from viruses to whales) interact and how species interact across ecosystems (from shallow ocean to deep) in ecosystem functioning novel experimental analyses will encompass biodiversity analyses at different levels, from viruses and prokaryotes to large vertebrates and span habitats from the intertidal to abyssal sediments, and from pelagic to benthic ecosystems. To include the smallest components of 4 the food webs (marine microbes) we will develop standardized methods to evaluate and compare functions to those of large organisms (macrophytes, fishes, marine mammals). We hypothesize, for example, that large organisms may play more important roles in provisional and recreational services, whereas microbial organisms are particularly important in delivery of regulatory services. Less studied systems (e.g., deep sea and polar regions) are particularly important in understanding specific responses and linkages among function and diversity across habitats. We hypothesize that functions and services may be more pronounced per unit area in shallower regions but greater per individual in the deep sea. (c) To understand whether biodiversity hot spots are also hot-spots of ecosystem services we will overlap standardized maps of biodiversity and ecosystem functions across different regions, habitats and organism types by collaborating with Theme “Current Baselines”. Overlying these maps at various spatial scales will demonstrate visually whether biodiversity hot spots overlap ecosystem function and service hotspots, and how they are related. Spatial autocorrelation analyses and GIS mapping will help to interpret spatial overlap and drivers of spatial variability. We hypothesize that biodiversity hotspots do not consistently coincide with function and service hotspots because some important functions and services depend largely on a single species or functional group. (d) Field investigations remain the key to understanding the impact of species loss and decline in functions in marine ecosystems. We will develop specific indicators of loss of functions and services, and use analysis of changes in biodiversity over time and space to identify tipping points of biodiversity loss that lead to major changes in ecosystem functioning and services. Census of Marine Life data offer a mechanism to evaluate potential global change impacts on biodiversity, ecosystem functioning, and services. Specifically, we will select regions and habitat types for this analysis where historical changes in marine biodiversity and ecosystems have been documented, and prioritize some of these areas for some of the above measurements and experiments. Of particular interest here are “unnatural” experiments of species removal (local extirpations or extinctions) and species additions (invasive species). We can then use a variety of scenario-based simulation modeling techniques to extrapolate past trends to future changes. (e) To understand the social, economic (and intangible) value of various habitat types and how their valuation depends on biodiversity, we will collaborate with social science studies that use interviews and local expertise to evaluate the importance of ecosystem services to humans (based on the Millennium Ecosystem Assessment classification). We will contrast different marine region/habitats to evaluate variability in importance of specific ecosystem services. Moreover we will collaborate with Theme “Understanding Change” to compare historical data of biodiversity and inferred ecosystem functioning to assess change and potential loss of ecosystem goods and services over the last centuries and decades. 2) Science tools The tools and technologies needed to achieve the objectives include: a) broad-scale databases on patterns of biodiversity, functions, and services; b) large-scale manipulative experiments that are conducive to meta-analyses; c) remote-sensing, GIS analyses, and molecular genetic tools (in collaboration with Theme “Current Baselines”; d) new approaches and technologies to collect data on biodiversity and on ecosystems functions, including in situ sensors (including biomass and productivity; in collaboration with Theme “Current Baselines”; e) advanced statistical tools; f) analysis of human use of marine natural 5 capital (in collaboration with Theme “Understanding Change” and g) collaboration with socio-economic scientists to communicate the importance of marine ecosystem services. 3) How a global reach/view will be integrated into research Theme members include scientists from all over the world with expertise on different biodiversity components from microbes to marine mammals, and habitats spanning from the tropics to high latitudes and from the intertidal to the deep sea. This coordinated, international approach will provide unprecedented, integrated knowledge of the different components of biodiversity and of their interactions. The global information we will acquire on biodiversity, ecosystem functioning, and services will provide a major scientific contribution to advise other global institutions such as GEO-BON, ILTER, ICES, and IPBES that provide direct policy advice. Implementation We propose to implement this program through a combined strategy of data meta-analysis and synthesis workshops and combined field and laboratory studies. Our first workshop will bring together ~20 biodiversity experts from around the world to undertake a meta-analysis on available data on biodiversity and ecosystem functioning with the dual objective of providing an initial evaluation of contributions of contrasting ecosystems around the world and identifying gaps and opportunities for coordinated international study. This workshop would not only produce a novel, publishable metaanalysis of current knowledge for a high-ranking, peer-review journal, but would also build the foundation for a detailed and coordinated international proposal to carry the theme to the next step. Moreover, workshop participants could then carry that knowledge to their national research communities to develop parallel proposals to national funding agencies around the world. We would also undertake a “proof of concept” study where workshop participants would undertake a small manipulative field study in their own geographic region of the world. During the workshop, we will establish the specific methodologies and protocols and agree on a timeline and scope for the experiment. For example, participants could undertake a small comparative study on the role of habitat complexity in biodiversity-ecosystem function interactions (seagrass or mangrove habitats vs adjacent bare sediments) and investigate the impact of species removal (simulating random and non-random extinctions). One of the main novelties of this study will be to include the microbial component and to investigate the impact of changing microbial functions (bacterial and archaeal taxa inhibited using different specific antibiotics) or diversity on ecosystem functions (e.g., production, rates of respiration and nutrient efflux from sediments). Caging studies will allow us to manipulate functional biodiversity (e.g., remove selectively large bioturbators from both systems) and help to elucidate the role of that functional group in decomposition processes and nutrient regeneration. At the same time a detailed analysis of the biodiversity (from microbial to macrobial species) and functions at different spatial scales will allow us to compare the findings gathered from manipulative experiments with those obtained from real world observations. Finally, a comparison of subarctic, temperate, and tropical systems from (generally) relatively species rich Pacific habitats in comparison with species poorer Atlantic habitats could provide an excellent basis for meta-analyses in a wide range of physically similar systems but with major differences in species composition and species richness. 6 Our second workshop would bring together a mixture of biodiversity experts with technology experts in biogeochemistry, physical oceanography and genetics, who would be charged with identifying new technologies and gaps for monitoring biodiversity and ecosystem functioning. This workshop would take place on collaboration with the biodiversity observation subtheme of Theme “Understanding and Predicting Change”. These initial workshops, meta-analyses, and proof of concept field studies would pave the way for the bulk of the research program, which would include the following components in the sequence listed. A major new proposal for observational studies, with a holistic approach to the study of biodiversity (from viruses to whales), including long-term components, to fill gaps and needs identified in the two workshops and meta-analyses. This proposal would include globally replicated experimental approaches to examine causal relationships among biodiversity and ecosystem functions and services. A major workshop partway through the above program to undertake meta-analysis of the data and observations collected at that point to identify priority areas (geographic, function, habitat) for the second phase of the program. A significant modeling component, that would build on the above efforts to create scenario building tools and applications A socio-economic analysis, which would consider economic and social aspects of biodiversity-ecosystem good and services relationships. This initiative would take place in parallel with the above activities, with frequent interchange of ideas between natural and socio-economic scientists. This initiative would also help to bridge the science-policy gap, and build a means of communicating scientific findings to those developing policy. Significance 1) Key deliverables 1. A global map of the biological/functional value of contrasting habitat types in the oceans 2. A global map of vulnerable ecosystems functions and services, and of compromised systems that could be restored 3. Future scenarios of the impact of climate change and other human perturbations on marine biodiversity and related ecosystem goods and services 4. An integrated studies on how small and large species interact within and across ecosystems (from the shallow ocean to the deep) and how this contributes to the delivery of ecosystem functioning 5. Identification of tipping points in ecosystem functioning as a result of marine biodiversity alteration 6. Science-based evaluation of ecosystem services in contrasting regions of the world that considers differences in resource use, economy, and culture. 7. Scientific outputs in international symposia and publication in international, peerreviewed journals. 8. Targeted workshops and reports for local stakeholders and policy makers on status and sustainability of ecosystem services. 9. Development of an interactive website and other applications (e.g. smartphone applications) to promote environmental education to a wider public. 7 2) Benefits to society Elucidating relationships between biodiversity, ecosystem functioning, and ecosystem services in the world oceans will provide essential knowledge for conservation and sustainable management of a wide range of ocean habitats. This information will provide strong impetus for the protection of specific habitats through the identification of marine biodiversity and ecosystem services hot spots that require most urgent protection. Recognizing increasing pressures for ocean use, it will also identify sustainable use options. This theme will thus help to set the criteria for the creation of regional marine protected areas as agreed in the Aichi Biodiversity Target set in 2010. Furthermore, prediction of future changes in marine ecosystem services will help determine levels of sustainable use of provisional services (seafood, genetic resources, etc.) and cultural services (recreation, ecotourism). This project will also provide the first quantitative estimates of ecosystem services in a wide range of major habitat types within the world ocean, providing unprecedented information for policy makers. By expanding the approach from the simple analysis of the biodiversity to the wider analysis of interactions between biodiversity and ecosystem good and services, the theme will contribute to global efforts to sustain marine natural capital for future generations. Proponents and participants 1) List names, affiliations, and area of expertise of key players Roberto Danovaro is Director of the Department of Life and Environmental Sciences at the Polytechnic University of Marche, Italy) and is full professor in Marine Biology and Ecology. His research is focused on deep-sea biodiversity and ecology, with a synecological and interdisciplinary approach devoted to the identification of the links between ecosystem functioning and the production of goods and services. r.danovaro@univpm.it Masahiro Nakaoka is a Professor and Director of Akkeshi Marine Station, Hokkaido University, Japan. His research focuses on marine benthic ecology, studying population and community patterns and processes in key coastal habitats such as seagrass bed, kelp forest and rocky intertidal shore. nakaoka@fsc.hokudai.ac.jp Paul Snelgrove is a Professor and Canada Research Chair in Boreal and Cold Ocean Systems at the Ocean Sciences Centre of Memorial University. He is also Director of the NSERC Canadian Healthy Oceans Network. His research focuses on biodiversity pattern and ecosystem functioning in sedimentary ecosystems from shallow water to the deep sea. psnelgro@mun.ca Lisandro Benedetti-Cecchi is a… Ferdinando Boero is a… Tasman Crowe is a… Emmett Duffy is a… Susanne Menden-Deuer is a… David Raffaelli is a… Martin Solan is a… 8 Simon F. Thrush is a… Jean-Éric Tremblay is a… Theme Biodiversity and ecosystem services Key participants Lisandro BenedettiCecchi Ferdinando Boero Tasman Crowe Emmett Duffy Susanne MendenDeuer David Raffaelli Martin Solan University of Pisa University of Salento University College Dublin/MARBEF Virginia Institute of Marine Science (VIMS) lbenedetti@biologia.unipi.it boero@unisalento.it tasman.crowe@ucd.ie jeduffy@vims.edu University of Rhode Island University of York University of Aberdeen smenden@gso.uri.edu david.raffaelli@york.ac.uk m.solan@abdn.ac.uk Simon F. 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