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The advances made by the GLOBEC programme are summarized in terms of what was learned from GLOBEC science, the science themes now emerging from GLOBEC results, and the implications of these for future interdisciplinary marine ecosystem research programmes. The fundamental changes in understanding of scales of interactions of marine ecosystems, alternative views of food webs, and the appreciation of the role of humans in marine ecosystem processes that have come from GLOBEC science are highlighted. Emerging themes related to scales and thresholds, human interactions with ecosystem change, and advances in modelling marine ecosystems provide the basis for future research that builds on the GLOBEC programme. The lessons learned from the GLOBEC programme highlight, and provide direction for, the many challenges that will have to be overcome to develop the integrative research programmes between the natural, social, and economic sciences that are needed to understand and sustain the world's ocean in an era of increasing change and uncertainty.

GLOBEC studies have greatly expanded our understanding of the structure and functioning of marine ecosystems, in particular demonstrating the importance of life history dynamics in determining the influence of physical processes on organisms in the ocean. The linkages between physical and biological processes were explored through novel approaches to experimentation in the laboratory, in the field, and through biophysical models of the coupled dynamics. New observations and the development of realistic physical circulation models have made it possible to quantitatively explore the relation between advection by large‐scale hydrodynamic fields, motions of actively behaving organisms at the scale of the individuals, and the response of organisms to dynamically evolving predator—prey fields. Scale dependence has also been demonstrated through observations that cover a wide geographic range and models that allow high resolution ranging from continental shelf to oceanic basin scales. The complexity of the interactions in marine ecosystems has required consideration of as many factors as possible while at the same time focusing on the primary factors, given the challenges of disentangling the complexity. These ideas and approaches to biophysical coupling are reviewed through presentation of the research that has been carried out during the GLOBEC programme over the past two decades.

This chapter discusses the role of climate variability and change and their effects on the marine environment. As the frequency of physical forcing increases, the biological changes progress from local effects on individuals at synoptic weather scales, towards regional effects on population dynamics at monthly to decadal scales, and over and across basins on systems ecology at multidecadal timescales and longer. The nature of the impact is size‐ and age‐dependent with generally greater and more rapid impacts on the smaller and younger individuals. The use of large‐scale climate indices to link climate forcing with ecological responses is highlighted as are the insights gained through comparative studies between ecosystems or between fish populations that inhabit different hydrographic regimes.

Marine environments provide a rich bounty of ecosystem services, including fish populations for harvest, beautiful places for recreation, shoreline structure that protects adjacent lands from storms, biogeochemical processes which regulate climate, and connections to human societies that offer cultural and spiritual benefits. In principle, marine ecosystem services are not fundamentally different from their terrestrial counterparts. In practice, however, the valuation and mapping of ecosystem services in marine environments is not as well developed as it is for terrestrial ecosystems. This chapter provides an overview of the services provided by marine environments, and presents a case study of mapping and modelling the flow of ecosystem services in Puget Sound – one of the first comprehensive attempts to understand the linkages between marine ecosystem structure, function, and the benefits delivered to people.

This chapter examines the impact of global change stressors on biodiversity — with an emphasis on the number, composition, and trait distribution of species in communities — and the functioning of multitrophic ocean and estuarine ecosystems. More specifically, it considers how ecological and biogeochemical processes, particularly benthic and pelagic marine ecosystems, are influenced by changes in composition and diversity in multilevel food webs. It first outlines how diversity is changing in oceans and estuaries and how such changes might affect ecosystem functioning. It then discusses experimental and observational studies on biodiversity-ecosystem function (BEF) in multitrophic systems, reviews several methodological and philosophical issues involved in transferring BEF academic research to applied conservation problems, and the link between biodiversity and ecosystem functioning in the Anthropocene.

The 1980 Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR) is a path-breaking example of the ecosystem approach to resource conservation and management. It essentially broke the mould in wildlife regulation, departing from the traditional approach of regulating exploitation of species or groups of species. Instead, CCAMLR adopts a modern multispecies ecosystem approach — an approach which now underpins a number of modern environmental treaties, including the 1992 Convention on Biological Diversity, which has adopted it ‘as a framework for the analysis and implementation of the objectives of the Convention’. In 1991, the negotiation of the Protocol on Environmental Protection to the Antarctic Treaty elevated ecosystem protection to a component of all activities in Antarctica. It designates Antarctica as a natural reserve, devoted to peace and science, and requires comprehensive protection of the Antarctic environment and dependent and associated ecosystems. Together the Protocol and CCAMLR comprehensively cover the marine and terrestrial ecosystems to the Antarctic. However, it is the marine ecosystem which contains most of Antarctica's flora and fauna, and where the CCAMLR pioneered an ecosystem approach to management. This chapter focuses on the ecosystem approach as it has developed under the CCAMLR. It then evaluates the Antarctic contribution to the protection of ecosystems under international law.

This chapter focuses on the past, present, and future of marine biodiversity. It first provides an overview of biodiversity and what it means and compares the biodiversity of marine and terrestrial ecosystems. It then looks at the evolution of marine biodiversity, its distribution, and how it is impacted by humans. It also discusses the relationship between global climate and marine biodiversity, asks whether marine biodiversity could be facing large-scale climate-induced extinction, examines additional impacts of carbon dioxide on the marine environment, and considers the influence of climate change on the problem of hypoxia and ‘dead zones’ in coastal marine ecosystems.

This chapter discusses current ecosystem responses to the input of whale detritus. It then estimates the effects of industrial whaling on the production of dead whales and speculates on the consequences of these changes for marine ecosystems. Finally, it proposes an experimental approach to test some of these speculations. Whale carcasses are end members in the spectrum of marine detritus, constituting the largest, most energy-rich organic particles in the ocean. Most great-whale carcasses sink essentially intact to the deep-sea floor, where they are recycled by a succession of scavenger, enrichment-opportunist, and sulfophilic assemblages. Although the flux of organic carbon in whale falls is small compared to total detrital flux, the massive energy concentrated in a whale fall can support a diverse deep-sea community.

This chapter examines how observational studies can help in the design, execution, and interpretation of biodiversity-ecosystem function relationships. It first analyses the heterogeneous nature of seafloor landscapes and how interactions between processes occurring on different temporal and spatial scales give rise to complex and interesting dynamics that characterise many benthic marine ecosystems. It then explores the role of observations in studying ecosystem functioning, assesses the relevance of scaling laws to BEF, and considers a more integrative approach to empirical research in BEF studies.

Due to its extensive deep-time history encompassing almost 600 million years, the fossil record offers important insights into changing biodiversity in marine ecosystems, inluding rapid diversification during the radiation of metazoans in the Ediacaran and the Cambrian explosion. This chapter examines three key biodiversity changes in history: the Ediacaran radiation of large multicellular eukaryotes, the Cambrian radiation of complex bilaterian-grade animals, and the end-Permian mass extinction. It discusses changes in biodiversity and their relation to various factors involved in ecosystem functioning such as bioturbation (biogenic mixing depth), functional diversity, and productivity. It also considers the link between species richness and functional diversity, the productivity-biodiversity relationship, and environmental changes during the late Paleozoic to early Mesozoic.

Hundreds of plant and animal species co-exist in marine ecosystems. More than 150 years ago, Charles Darwin recognised explicitly the importance of species interactions by invoking the concept of a ‘tangled bank’ of species. These interactions play an important role in the maintenance of ecological stability in the face of natural and anthropogenic disturbances. However, the mechanisms underlying ecosystem stability in the face of environmental change remain poorly understood. This chapter examines the importance of body size, abundance, and food-web structure for ecosystem functioning. It considers the building blocks of food webs, body mass, species abundance, and predator-prey interactions, as well as the interrelationships between body mass and trophic position. It presents examples that are not restricted to marine ecosystems in order to understand the drivers and consequences of biodiversity change in a wide range of ecosystems. It also discusses the relevance of body mass to biodiversity-ecosystem function research.

Changes in seawater chemistry driven by ocean acidification are altering the physiological performance and ecology of marine biota. Ocean acidification effects on calcification, photosynthesis, and neurophysiological functions differ between taxa and life stages, and such differential responses can lead to important ecological shifts in populations and communities. Two of the main challenges in predicting the ecological effects of ocean acidification are (1) integration across these levels of organization, from seawater chemistry to multi-species interactions, and (2) assessing the synergistic effect with other climate stressors that operate in parallel. While the literature is full of examples of taxa with high sensitivity, a small proportion of taxa appears resilient or displays some ability to acclimate or adapt to changes in inorganic carbon chemistry. Knowledge of the specific energetic costs of acclimation to ocean acidification is scarce, but energetic trade-offs are likely required in these resilient types to maintain physiological processes such as calcification under low pH conditions. Ocean acidification must be investigated in the context of other climate stressors, and new depth and temperature ranges will require complex adaptation strategies. High latitude and upwelling regions are already experiencing pronounced chemical shifts and, in some cases, seasonal calcium carbonate undersaturation, and many calcifiers are responding physiologically and ecologically to those changes. Although there is substantial uncertainty in the predictions of future ecosystem structures, it appears inevitable that the composition and function of many marine ecosystems will be altered in the near future due to the rapidly progressing acidification and warming of the oceans.

Often highly intelligent with sophisticated communication systems, marine mammals are a fundamental component of marine ecosystems around the world. Archaeological data demonstrate that human impacts on marine mammals in the more distant past were substantial and suggest that much remains to be learned about the prehistory of these animals. This book brings together researchers from a variety of disciplines seeking to integrate archaeology, history, and ecology to understand the ancient and modern interactions between pinnipeds, sea otters, people, and marine ecosystems. It investigates the influence of ancient peoples on the biogeography, breeding behavior, and abundance of seals and sea lions over the last several millennia in the northeastern Pacific Coast. Following a brief discussion of archaeology and human environmental impacts, this chapter provides an overview of the ecology of pinnipeds and sea otters in the northeastern Pacific, emphasizing the historical and modern transformations of these various populations.

R. C. Francis, J. Field, D. Holmgren and A. Strom traces the historical record of the west coast North American marine ecosystem through historical, paleoclimatological, and environmental disciplines in order to understand its development over centuries of change. The results show that large-scale climate forcing is a core factor in the fluctuating stock of coastal species over the eighteenth, nineteenth, and twentieth centuries.

This chapter follows the size-structure of the entire marine ecosystem. It shows how the Sheldon spectrum emerges from predator–prey interactions and the limitations that physics and physiology place on individual organisms. How predator–prey interactions and physiological limitations scale with body size are the central assumptions in size spectrum theory. To that end, this chapter first defines body size and size spectrum. Next, it shows how central aspects of individual physiology scale with size: metabolism, clearance rate, and prey size preference. On that basis, it is possible to derive a power-law representation of the size spectrum by considering a balance between the needs of an organism (its metabolism) and the encountered prey, which is determined by the spectrum, the clearance rate, and the size preference. Lastly, the chapter uses the solution of the size spectrum to derive the expected size scaling of predation mortality.

The Lipalian or Vendian Period, which occurred 600–541 million years ago, begins and ends with global environmental perturbations. It begins as the worst glaciation on record draws to a close. It ends with a sudden appearance of abundant skeletonized animals that mark the beginning of Cambrian ecology. Several key events in Earth history occur during the Lipalian, bracketed between severe glaciation and the initiation of modern marine ecosystems. The most notable of these events is the appearance of an unusual and conspicuous marine biota, the “Garden of Ediacara.” This biota appears to have characteristics inherited from its sojourn beneath the ice. This chapter examines the role the cryophilic biota, consisting largely of cyanobacteria and chryosphyte and chlorophyte algae, may have played in ending the great ice age. It is hypothesized here that these microbes induced albedo reductions and other changes that rapidly improved global climate.