To tip or not to tip: The Window of Tipping Point Analysis for social‐ecological systems

We introduce six steps to define a “Window of Tipping Point Analysis” which serves as a framework to increase the understanding of processes and tipping points in social-ecological systems. We apply the Window of Tipping Point Analysis to a mathematical model and two case studies (i.e., Baltic Sea and the Humboldt Current Upwelling system), focusing on three aspects. In “to tip or be tipped” we look at agency in preventing (or driving) tipping. In “to be tipped or not to be tipped” we discuss intertemporal developments and chosen time periods for delineating regime shifts. In “to tip or not to tip” we discuss the desirability of states and their relation to the elements included. We argue that agency in tipping-point management, the occurrence of tipping points, and desirable states depend on the window chosen for the analysis

Five social science intervention areas for ocean sustainability initiatives

Ocean sustainability initiatives – in research, policy, management and development – will be more effective in delivering comprehensive benefits when they proactively engage with, invest in and use social knowledge. We synthesize five intervention areas for social engagement and collaboration with marine social scientists, and in doing so we appeal to all ocean science disciplines and non-academics working in ocean initiatives in industry, government, funding agencies and civil society. The five social intervention areas are: (1) Using ethics to guide decision-making, (2) Improving governance, (3) Aligning human behavior with goals and values, (4) Addressing impacts on people, and (5) Building transdisciplinary partnerships and co-producing sustainability transformation pathways. These focal areas can guide the four phases of most ocean sustainability initiatives (Intention, Design, Implementation, Evaluation) to improve social benefits and avoid harm. Early integration of social knowledge from the five areas during intention setting and design phases offers the deepest potential for delivering benefits. Later stage collaborations can leverage opportunities in existing projects to reflect and learn while improving impact assessments, transparency and reporting for future activities

World Ocean Review 2015 : living with the oceans 5. Coasts - a vital habitat under pressure

The fifth World Ocean Review (WOR) explores the coastal habitat and the diverse expectations upon this habitat. It provides a glimpse into millions of years of history, elucidates the theory of continental drift and discusses the many ways in which coasts have changed. It also illustrates how the diverse ecosystem services rendered by the coasts are being subjected to increasing pressure, and profiles measures that will be necessary in the future to respond effectively to the threats from both climate change and natural disasters

World ocean review: Mit den Meeren leben 5. Die Küsten - ein wertvoller Lebensraum unter Druck

Die fünfte Ausgabe des „World Ocean Review“ (WOR) beschäftigt sich mit dem Lebensraum Küste und den vielfältigen Erwartungen, die an diesen Lebensraum gestellt werden. Der WOR 5 gibt einen Einblik in die über Jahrmillionen zurückreichende Geschichte, erläutert die Theorie der Kontinentalveschiebung und erörtert wie sich das Gesicht der Küsten verändert hat. Er zeigt auf, wie die vielfältigen Ökosystemleistungen der Küsten immer mehr unter Druck geraten und stellt Maßnahmen vor, die in Zukunft notwendig sein werden, um den Bedrohungen durch Klimawandel und Naturkatastrophen Herr zu werden

Ecological and socio-economic feasibility of scallop bottom culture in Sechura Bay, Northern Peru

Sechura Bay in northern Peru recently developed into a center for the cultivation of the Peruvian bay scallop Argopecten purpuratus. Today, aquaculture-related activities constitute an important socio-economic sector for the region, with about 25000 people involved and annual export values of 150 million US$. By providing settling substrate to other organisms in an otherwise soft-bottom habitat the bivalves may potentially function as ecosystem engineers in the system. Overstocking of scallops may cause mass mortalities, potentially impacting other organisms and overall ecosystem functioning. Accordingly, the assessment of the current situation and the determination of long-term sustainable limits are crucial. The overall objective of this thesis was to develop a holistic approach for the ecosystem-based exploration of bivalve aquaculture impact and the estimation of ECC that should be applicable to other coastal settings. The results of the thesis suggest that scallop aquaculture has essentially altered the systema s trophic flow structure and functioning. As a major output, a general ecosystem approach to aquaculture is proposed that is based on several novel methodologies for the integrated assessment of (1) impacts of aquaculture on ecosystem functioning and resilience, (2) effects of management decisions on harvest through ECC simulations, and (3) societal and environmental factors important for long-term sustainability. Results are expected to guide local decision makers to contribute substantially to our understanding of ecosystem responses to bivalve aquaculture. With an ever expanding aquaculture industry worldwide, the approach provides guidance for future studies in different aquaculture settings that aim at determining sustainable limits to growth

Ökologische und sozio-ökonomische Machbarkeit einer Pilgermuschelbodenkultur in der Sechurabucht, Nordperu

Sechura Bay in northern Peru recently developed into a center for the cultivation of the Peruvian bay scallop Argopecten purpuratus. Today, aquaculture-related activities constitute an important socio-economic sector for the region, with about 25000 people involved and annual export values of 150 million US$. By providing settling substrate to other organisms in an otherwise soft-bottom habitat the bivalves may potentially function as ecosystem engineers in the system. Overstocking of scallops may cause mass mortalities, potentially impacting other organisms and overall ecosystem functioning. Accordingly, the assessment of the current situation and the determination of long-term sustainable limits are crucial. The overall objective of this thesis was to develop a holistic approach for the ecosystem-based exploration of bivalve aquaculture impact and the estimation of ECC that should be applicable to other coastal settings. The results of the thesis suggest that scallop aquaculture has essentially altered the systema s trophic flow structure and functioning. As a major output, a general ecosystem approach to aquaculture is proposed that is based on several novel methodologies for the integrated assessment of (1) impacts of aquaculture on ecosystem functioning and resilience, (2) effects of management decisions on harvest through ECC simulations, and (3) societal and environmental factors important for long-term sustainability. Results are expected to guide local decision makers to contribute substantially to our understanding of ecosystem responses to bivalve aquaculture. With an ever expanding aquaculture industry worldwide, the approach provides guidance for future studies in different aquaculture settings that aim at determining sustainable limits to growth

Beyond the bay: Biophysical simulations of disease dispersal suggest broadening spatial scales for aquaculture carrying capacity

One major societal challenge is meeting the constantly increasing demand for (sea)food in a sustainable way. Marine aquaculture offers large production potential, but it is crucial to define production limits that maintain ocean health. The concept of aquaculture carrying capacity (CC) provides such limits for locally defined areas. However, the ocean is subject to large- and small-scale dynamics, and far-reaching effects of aquaculture (e.g., the spread of marine diseases with ocean currents) are currently neglected in CC estimates. Here we predict potential “impact areas” with a biophysical simulation approach and find them to be larger than those currently considered in CC estimates. We suggest “impact areas” as a measure for spatial connectivity with the requirement to define what is an acceptable “impact area” case specifically. The proposed approach is applicable to various marine aquaculture systems and would drive CC estimates toward improved sustainability by considering the impact and risk of dispersal beyond the immediately adjacent area

Evaluating ecosystem impacts of gear regulations in a data-limited fishery—comparing approaches to estimate predator–prey interactions in Ecopath with Ecosim

Ecosystem models, such as Ecopath with Ecosim (EwE), are useful tools for developing ecosystem-based management strategies. Model development, however, requires data for the estimation of input parameters including time series for calibration. Most small-scale fisheries lack such information, making it difficult to reliably use ecosystem models for management strategy exploration. This is the case for the Chwaka Bay fishery (Zanzibar), where an increase in dragnets has led to concerns for unsustainable development. While EwE could help to explore the impacts of gear regulations in the bay, this is hampered by the lack of time series to estimate the predator–prey interactions (vulnerabilities) in the model. Here, we explore available approaches for estimating the vulnerabilities to simulate the effects of a dragnet prohibition with and without reallocation of fishing effort. Simulations suggest that banning dragnets would be beneficial for the fishing community judged by the increase in biomass of functional groups and fishers’ profits, but not if dragnet fishers were to continue fishing in the bay by reallocating to other gears, indicated by the reduced fish biomass and fishers’ profits. The overall trend (decreasing or increasing) in the changes of functional groups, ecosystem indicators, and profits were relatively consistent across vulnerability settings, illustrating that an unfitted EwE model can be used for qualitative management strategy exploration.En prensa2,27

ScRNA-seq defines dynamic T-cell subsets in longitudinal colon and peripheral blood samples in immune checkpoint inhibitor-induced colitis

Immune checkpoint inhibitors (ICIs) are increasingly being used to manage multiple tumor types. Unfortunately, immune-related adverse events affect up to 60% of recipients, often leading to treatment discontinuation in settings where few alternative cancer therapies may be available. Checkpoint inhibitor induced colitis (ICI-colitis) is a common toxicity for which the underlying mechanisms are poorly defined. To better understand the changing colon-specific and peripheral immune environments over the course of progression and treatment of colitis, we collected blood and colon tissue from a patient with Merkel cell carcinoma who developed colitis on treatment with pembrolizumab. We performed single-cell RNA sequencing and T-cell receptor sequencing on samples collected before, during and after pembrolizumab and after various interventions to mitigate toxicity. We report T-cells populations defined by cytotoxicity, memory, and proliferation markers at various stages of colitis. We show preferential depletion of CD8+ T cells with biologic therapy and nominate both circulating and colon-resident T-cell subsets as potential drivers of inflammation and response to immune suppression. Our findings highlight the need for further exploration of the colon immune environment and rationalize future studies evaluating biologics for ICI-colitis, including in the context of ICI re-challenge