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Drawing on extensive research, this study provides an overview of the causes and consequences of the loss of natural resources. It explores key ecosystems (forests, marine systems, wetlands) and examines the management challenges involved in protecting these systems from destruction.

Much of the Earth’s biosphere has been appropriated for the production of harvestable biomass in the form of food, fuel and fibre. Here we show that the simplification and intensification of these systems and their growing connection to international markets has yielded a global production ecosystem that is homogenous, highly connected and characterized by weakened internal feedbacks. We argue that these features converge to yield high and predictable supplies of biomass in the short term, but create conditions for novel and pervasive risks to emerge and interact in the longer term. Steering the global production ecosystem towards a sustainable trajectory will require the redirection of finance, increased transparency and traceability in supply chains, and the participation of a multitude of players, including integrated ‘keystone actors’ such as multinational corporations. This Perspective examines the global production ecosystem through the lenses of connectivity, diversity and feedback, and proposes measures that will increase its stability and sustainability.

Key insights on needs in urban regional governance - Global urbanization (the increasing concentration in urban settlements of the increasing world population), is a driver and accelerator of shifts in diversity, new cross-scale interactions, decoupling from ecological processes, increasing risk and exposure to shocks. Responding to the challenges of urbanization demands fresh commitments to a city–regional perspective in ways that are explictly embedded in the Anthopocene bio- techno- and noospheres, to extend existing understanding of the city–nature nexus and regional scale. Three key dimensions of cities that constrain or enable constructive, cross scale responses to disturbances and extreme events include 1) shifting diversity, 2) shifting connectivity and modularity, and 3) shifting complexity. These three dimensions are characteristic of current urban processes and offer potential intervention points for local to global action.

Degradation of coral reefs is often associated with changes in community structure where macroalgae become the dominant benthic life form. These phase shifts can be difficult to reverse. The debate on coral reef phase shifts has not focused on reports of coral reefs becoming dominated by other life forms following disturbance. A review of the primary and grey literature indicates that reefs dominated by corallimorpharia, soft corals, sponges and sea urchins can enter an alternative state as a result of a phase shift. Shifts can be triggered by pulse disturbances that cause large-scale coral mortality, and may become stable as a result of positive feedback mechanisms. However, they may differ from the archetypical coral–macroalgae shift, depending on the factors driving the shift; whereas coral–macroalgae and coral–urchin shifts seem to be driven by loss of top-down control through overfishing, shifts to corallimorpharian, soft coral and sponge dominance seem more associated with changes in bottom-up dynamics. Understanding the differences and similarities in mechanisms that cause and maintain this variety of alternative states will aid management aimed at preventing and reversing phase shifts of coral reefs.

Unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. This lack of diversity may increase risks of ecological and economic disruptions. Centuries of intense fishing have extirpated most apex predators in the Gulf of Maine (United States and Canada), effectively creating an American lobster (Homarus americanusj monoculture. Over the past 20 years, the economic diversity of marine resources harvested in Maine has declined by almost 70%. Today, over 80% of the value of Maine's fish and seafood landings is from highly abundant lobsters. Inflationcorrected income from lobsters in Maine has steadily increased by nearly 400% since 1985. Fisheries managers, policy makers, and fishers view this as a success. However, such lucrative monocultures increase the social and ecological consequences of future declines in lobsters. In southern New England, disease and stresses related to increases in ocean temperature resulted in more than a 70% decline in lobster abundance, prompting managers to propose closing that fishery. A similar collapse in Maine could fundamentally disrupt the social and economic foundation of its coast. We suggest the current success of Maine's lobster fishery is a gilded trap. Gilded traps are a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences. Large financial gain creates a strong reinforcing feedback that deepens the trap. Avoiding or escaping gilded traps requires managing for increased biological and economic diversity. This is difficult to do prior to a crisis while financial incentives for maintaining the status quo are large. The long-term challenge is to shift fisheries management away from single species toward integrated social-ecological approaches that diversify local ecosystems, societies, and economies. La pesca no sustentable simplifica las cadenas alimenticias y, como la acuicultura, puede resultar en una dependencia en unas cuantas especies valiosas económicamente. Esta falta de biodiversidad puede incrementar los riesgos de disrupciones ecológicas y económicas. Siglos de pesca intensiva ban extirpado a la mayoría de los depredadores superiores en el Golfo de Maine (E.U.A. y Canadá), creando efectivamente un monocultivo de langosta americana Homarus americanus). Durante los últimos 20 años, la diversidad económica de los recursos marinos cosechados en Maine ha declinado en casi 70%. Ahora, más de 80% del valor de las capturas de peces y mariscos consiste en langostas que son muy abundantes. El ingreso, corregido para la inflación, por langostas ha incrementado consistentemente en casi 400% desde 1985. Manejadores de pesquerías, políticos y Pescadores ven esto como un éxito. Sin embargo, tales monocultivos lucrativos incrementan las consecuencias sociales y ecológicas de declinaciones de langostas en el futuro. En el sur de Nueva Inglaterra, las enfermedades y los estreses relacionados con incrementos en la temperatura del océano resultaron en una declinación de mas de 70% en la abundancia de langostas, lo que obligó a la propuesta del cierre de esa pesquería. Un colapso similar en Maine podría desestabilizar la base social y económica de su costa. Sugerimos que el éxito actual de la pesquería de langosta en Maine es una trampa dorada. Las trampas doradas son un tipo de trampa social en el que las acciones colectivas derivadas de oportunidades atractivas económicamente sobrepasan a las preocupaciones por los riesgos o consecuencias ecológicas y sociales asociadas. El gran ingreso financiero crea una fuerte retroalimentación reforzante que profundiza la trampa. Escapar de o evitar las trampas doradas requiere de manejo para el incremento de la diversidad biológica y ecológica. Esto es difícil de hacer antes de una crisis mientras los incentivos financieros para mantener el status quo son grandes. El reto a largo plazo es cambiar el manejo de pesquerías de una sola especie hacia enfoques sociales-ecológicos integrados que diversifiquen los ecosistemas, las sociedades y las economías locales.

Manage local stressors to promote resilience to global change Although some ecosystem responses to climate change are gradual, many ecosystems react in highly nonlinear ways. They show little response until a threshold or tipping point is reached where even a small perturbation may trigger collapse into a state from which recovery is difficult ( 1 ). Increasing evidence shows that the critical climate level for such collapse may be altered by conditions that can be managed locally. These synergies between local stressors and climate change provide potential opportunities for proactive management. Although their clarity and scale make such local approaches more conducive to action than global greenhouse gas management, crises in iconic UNESCO World Heritage sites illustrate that such stewardship is at risk of failing.

The worldwide decline of coral reefs calls for an urgent reassessment of current management practices. Confronting large-scale crises requires a major scaling-up of management efforts based on an improved understanding of the ecological processes that underlie reef resilience. Managing for improved resilience, incorporating the role of human activity in shaping ecosystems, provides a basis for coping with uncertainty, future changes and ecological surprises. Here we review the ecological roles of critical functional groups (for both corals and reef fishes) that are fundamental to understanding resilience and avoiding phase shifts from coral dominance to less desirable, degraded ecosystems. We identify striking biogeographic differences in the species richness and composition of functional groups, which highlight the vulnerability of Caribbean reef ecosystems. These findings have profound implications for restoration of degraded reefs, management of fisheries, and the focus on marine protected areas and biodiversity hotspots as priorities for conservation.

The United Nations conference in Rio de Janeiro in June is an important opportunity to improve the institutional framework for sustainable development. Science assessments indicate that human activities are moving several of Earth's sub-systems outside the range of natural variability typical for the previous 500,000 years ( 1 , 2 ). Human societies must now change course and steer away from critical tipping points in the Earth system that might lead to rapid and irreversible change ( 3 ). This requires fundamental reorientation and restructuring of national and international institutions toward more effective Earth system governance and planetary stewardship.

The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming.

Resilience to specified kinds of disasters is an active area of research and practice. However, rare or unprecedented disturbances that are unusually intense or extensive require a more broad-spectrum type of resilience. General resilience is the capacity of social-ecological systems to adapt or transform in response to unfamiliar, unexpected and extreme shocks. Conditions that enable general resilience include diversity, modularity, openness, reserves, feedbacks, nestedness, monitoring, leadership, and trust. Processes for building general resilience are an emerging and crucially important area of research.