From the Editor-in-Chief of the Bulletin of the Ecological Society of America
In 1988 the Ecological Society of America put together “The Sustainable Biosphere Initiative: an Ecological Agenda” (SBI) authored by then ESA President Jane Lubchenco and 15 other leading ecologists. This document had an important impact on the research programs of ecologists around the world. The report was cited hundreds of times, and more importantly, it also influenced many outside of the scientific community.
In this issue of the ESA Bulletin you'll find an effort that has branched off from SBI and related initiatives. ESA President Mary Power and President-elect Terry Chapin have compiled case studies from diverse contributors, ESA members and others, that address the theme “Toward a Planetary Stewardship: paths towards resilience and sustainability in a changing world.” The efforts discussed range from sustainable community-based fisheries and forests through solar and water management alternatives to direct trade in support of coffee and cacao growers. Some of these themes will be explored further in a special session at the ESA Annual Meeting in August, entitled “Implementing Ecosystem Stewardship at the Local Level.” Further, Power and Chapin propose in the future to use the ESA Bulletin as a forum for discussion of how planetary stewardship is to be accomplished. A new section in the Bulletin will be used to report on case studies, examples, and principles that have been used, successfully, to encourage and develop sustainability and resilience at the planetary scale. In the next issue of the Bulletin you'll find a more detailed discussion of how this new refereed section will work.
Planetary Stewardship in a Changing World: Paths Towards Resilience and Sustainability
Ecologists are increasingly engaged in collaborative efforts to slow or reverse the stress placed on Earth's life support systems by “business as usual” during the 19th and 20th centuries. Current collapses of local economies and natural ecosystems suggest that both must be reorganized and managed in ways that better sustain critical functions through a future of environmental instability and directional change. As Chapin et al. (2010) state:
There is no region so resilient that policy makers and managers can ignore potential [planetary] threshold changes…or any region that is beyond hope of substantial enhancement of well-being, adaptive capacity, and resilience. Sustaining ecosystem services and livelihoods will, however, require reconnecting people's perceptions, values, institutions, actions and governance systems to the dynamics of the biosphere through active ecosystem stewardship.
They go on to emphasize the importance of informal networks of individuals who seize opportunities for change, often following local system collapse, and provide fresh vision for transformations rather than submitting to the inertial tendency of established governance to rebuild the pre-crisis system.
The ~10,000 members of the Ecological Society of America include and interact with earth, atmospheric, and social scientists, as well as economists engaged with global dimensions of this challenge. On the other hand, our membership and valued collaborators also include individuals with long-term, often intergenerational, traditional or local knowledge of the ecosystems from which they draw their livelihoods (Fig. 1). These diverse traditional and local knowledge communities are rethinking how to sustain livelihoods while restoring and protecting their home ecosystems from future degradation. Some general strategies have been proposed for guiding social-ecological systems toward more favorable trajectories (Leopold 1942, Meadows 1999, Clark and Dickson 2003, Turner et al. 2003, Chapin et al. 2010). In any particular system, however, our predictive understanding is limited by complex local dynamics playing out against a backdrop of directional environmental change, buffeted by increasing variability, and linked to cross-scale interactions. More empirical case studies of transformational successes, and failures, are needed if we are to develop theory useful for guiding change in new specific situations.
Our purpose in initiating this forum in the Bulletin of the Ecological Society of America is to capture and communicate ideas and insights that arise from particular efforts, yet may be useful considerations for guiding change in other social–ecological systems. We have had exciting conversations with a number of individuals, ESA members and others, who are involved in efforts to enhance sustainability and resilience at local, regional, or global scales. Here we present the first 11 contributions.
The Karuk Tribe World Renewal Vision (Box 1 by Frank Lake, Bill Tripp, and Ron Reed) explores how the ecosystem goods (foods and cultural materials) and services (fire protection and hydrologic resilience) might be recovered as tribal management practices are restored to their ancestral watersheds around the Middle Klamath River in northern California. In southwestern U.S. rangelands and prairies, “grassroots collaboratives, where ranching and conservation interests align behind science-based approaches to stewardship” (in the words of Tom Sisk, Box 2) have shown that natural prairie ecosystems can be recovered and maintained in states more resilient to drought (see also Sayre 2005). Scientists and program directors from The Nature Conservancy have teamed with local fishers and regulatory agencies along the central California Coast to “rebuild a sustainable hook-and-line fishery on the rubble of a collapsed trawl fishery” (M. Bell, personal communication; see Box 3 by Mary Gleason, Michael Bell, Chuck Cook, and Steve Rienecke). John Rogers, in Box 4, writes about the Redwood Forest Foundation Inc.'s progress toward rebuilding a community-based, sustainable redwood forest in the steep and geologically fragile California North Coast, where previous industrial timber harvest has left major restoration challenges. In Box 5, Lee Gross explains the challenges to stewardship facing Dominican Republic coffee farmers, who recognize that shade coffee polycultures conserve water, provide other household resources, and support native birds, but nevertheless, see land use in their region trending toward less sustainable monoculture crops. Given our increasingly networked world and economy, informed consumers in wealthy countries who vote with their pocketbooks are an important part of such solutions—Box 6 gives us a very personal view of the transformation of one consumer toward market support of direct trade chocolate.
Box 1. The Karuk Tribe, Planetary Stewardship, and World Renewal on the Middle Klamath River, California.
F. K. Lake, USFS-PSW; W. Tripp and R. Reed, Karuk Tribe, Happy Camp, California
In the Karuk Tribe's worldview, planetary stewardship is maintained through the place-based spiritual and cultural philosophy of World Renewal. A philosophy of Renewal reaffirms the responsibility of humans as stewards as well as a critical ecosystem component. The Tribe believes in renewal of the human–environment relationship that is compatible with ecological processes, promotes a sustainable economy, and increases ecosystem resilience.
Karuk traditional ecological knowledge (TEK) supports an approach where all species, habitats, and their relationships are valued. TEK of ecological processes tells us that species and communities are susceptible and resilient to disturbances (Berkes et al. 2000, Anderson 2005). The Karuk Tribe uses TEK to guide management to enhance resource resilience and ensure sustainability.
The Karuk Tribe utilizes TEK and prescribed fire to reduce undesired consequences of wildfires. The Tribe's knowledge of climate and weather guides its use of fire in order to protect vulnerable habitats and species while increasing ecosystem resilience to climate change. The way the Tribe uses fire fosters the quality and abundance of resources the Tribe and other species depend on, from ridges to rivers (Anderson 2005, Skinner et al. 2006). Tribal knowledge recognizes the broad, landscape-scale relationships between fire, vegetation, soil moisture and transpiration, hydrology–water yield, and aquatic communities (Biswell 1999, Skinner et al. 2006). For generations, the Tribe has recognized the landscape's dependence on seasonal fire-induced change. For example, oak acorn productivity is affected by individual tree response to broader environmental conditions and ecosystem processes. Acorn abundance, an “ecosystem good,” is linked to wildland fire's “service,” and enhanced through the role of humans as stewards and fire managers (Anderson 2005). Additionally, woodpeckers, as indicators of terrestrial productivity and spiritual wealth, and Spring Chinook salmon, as indicators of aquatic health and watershed connectivity, are managed as cultural barometers of ecological integrity.
The relationship of the Karuk people and place has been disrupted since the 1850s European–American settlement of the mid-Klamath brought industries based on resource extraction, such as mining, timber harvest and associated fire suppression, dams (and other hydrologic alterations), and commercial fishing. Thus, the long-term (renewal) focus of tribal stewardship systems was replaced with a short-term profit emphasis of western resource extraction, as well as single-species management (Bright 1978).
Currently, resource management regimes are legally required to use best available science. The Tribe believes research and monitoring should focus on adaptive management and interdependent ecosystem functions to improve applicability of science for the Klamath Basin (Berkes et al. 2000). Additionally, land management should incorporate tribal management approaches in both planning and implementation. Following a tribal-based model, adaptive management would be guided by our World Renewal ceremonies, TEK, cumulative observations of ecological interactions, and our interdependency on resources within global social–ecological systems (Berkes et al. 2000, Anderson 2005).
The Karuk Tribe is currently developing an Eco-cultural Resources Management Plan that incorporates tribal perspectives. This plan seeks to unify principles of ecological restoration with tribal community needs in a holistic fashion. The tribe is monitoring results and documenting the effectiveness of their ecosystem management practices and wants to expand collaborative research efforts. For additional information or a summary of research and monitoring needs, contact the Karuk Tribe's Department of Natural Resources.
Anderson, M. K. 2005. Tending the wild: Native American knowledge and the management of California's natural resources. University of California Press, Berkeley, California, USA.
Berkes, F. , Colding, J. , and Folke, C. . 2000. Rediscovery of Traditional Ecological Knowledge as adaptive management. Ecological Applications10: 1251–1262.
Biswell, H. H. 1999. Prescribed burning in California wildlands vegetation management. First edition 1989. Foreword by J. Agee. University of California Press, Berkeley, California, USA.
Bright, W. 1979. Karok. Pages: 180–189in Heizer, R. F. , editor. California, Volume 8. Handbook of North American Indians. Smithsonian Institution, Washington, D.C., USA.
Skinner, C. N. , Taylor, A. H. , and Agee, J. K. . 2006. Klamath Mountains bioregion. Chapter 9. Pages 170–194in Sugihara, N. G. , Van Wagtendonk, J. W. , Shaffer, K. E. , Fites-Kaufman, J. , and Thode, A. E. , editors. Fire in California's ecosystems. University of California Press, Berkeley, California, USA.
Box 2. Ranching, Local Ecological Knowledge, and the Stewardship Of Public Lands.
T. D. Sisk, Northern Arizona University
America's grasslands are among its most endangered ecosystems (Noss et al. 1995), and livestock grazing is among the most controversial uses of our public lands (e.g., Brown and McDonald 1995). For decades, social and political forces have clashed over grazing, igniting controversies that have stymied policy reform. Yet amidst this debate, many ranching families, conservation groups, public officials, and engaged citizens have come together to find practical ways to link sustainable grazing with conservation objectives on the West's working landscapes. In so doing, these groups have highlighted the need for improved stewardship, but also recognized a suite of public services provided by the ranching community, including retention of open space and wildlife habitat, oversight of exploding recreation, and restoration of degraded lands and watersheds (Silbert et al. 2007).
Furthermore, the detailed intergeneration knowledge of local ecosystems held in ranching families is increasingly valuable in this era of rapid environmental change. In the Grand Canyon region, two ambitious efforts illustrate the diversity of efforts to rethink and reorient the social and ecological systems that intertwine on our public lands. In the early 1990's, two ranching families joined with former critics in the environmental community to form the Diablo Trust, a collaborative management group that has moved controversy out of the courtroom and onto the public lands, where research monitoring informs ranch practices, conservation projects, and policy reform (e.g., Munoz-Erikson et al. 2009). On the North Rim of the Grand Canyon, another collaborative effort came together when the Grand Canyon Trust, a leading conservation organization, purchased the historic Kane and Two-mile Ranches and entered the livestock business in an effort to reform from within, linking ranching with overarching commitments to ecosystem restoration and biodiversity conservation across 380,000 ha of public land (Sisk et al., in press).
These bold experiments emerged in strikingly different fashion to address a common challenge: improving the stewardship of public lands and resources in an era of rapid social and ecological change. Public/private partnerships are not new to the public rangelands of the West, but the emergence of grassroots collaboratives, where ranching and conservation interests align behind science-based approaches to stewardship, is novel and presents a rare opportunity to reorient public lands management toward ecosystem recovery, sustainable use, and resilience. Rewarding the ranching families who apply local ecological knowledge to solve emerging land use challenges will be critical to successful stewardship, as will support for the collaborative groups that represent the diverse values of our complex, pluralistic society.
Brown, J. H. , and McDonald, W. . 1995. Livestock grazing and conservation on southwestern rangelands. Conservation Biology9: 1644–1647.
Muñoz-Erickson, T. , Aguilar-Gonzáles, B. , Loeser, M. R. , and Sisk, T. D. . 2009. A framework to evaluate ecological and social outcomes of collaborative management: lessons from implementation with a northern Arizona collaborative group. Environmental Management45: 132–144.
Noss, R. F. , LaRoe, E. T., III , and Scott, J. M. . 1995. Endangered ecosystems of the United States: a preliminary assessment of loss and degradation. National Biological Service Biological Report 28. U.S. Department of the Interior, Washington, D.C., USA.
Silbert, S. , Chandler, G. , and Nabhan, G.P. , editors. 2007. Five ways to value working landscapes of the West. Center for Sustainable Environments, Northern Arizona University, Flagstaff, Arizona, USA.
Sisk, T. D. , and 13 co-authors. In press. Integrating restoration and conservation objectives at the landscape scale: The Kane and Two-mile Ranch project. In van Riper, C. III , Wakeling, B.W. , and Sisk, T. D. , editors. The Colorado Plateau IV: Integrating research and resources management for effective conservation. University of Arizona Press, Tucson, Arizona, USA.
Box 3. Transforming an Ailing Fishery: California's Central Coast Groundfish Project
Mary Gleason, Michael Bell, Chuck Cook, Steve Rienecke, The Nature Conservancy, California, USA
The Nature Conservancy (the Conservancy), with a mission of biodiversity protection, has long recognized the insufficiency of a protected-areas strategy alone, and the importance of conservation in places where people live and work. At the same time, we see the need for a more strategic scientific approach for engaging in sustainable harvest strategies and for determining the line between sustainable and unsustainable use. For wild-caught fisheries, which are dependent on healthy coastal and marine ecosystems, moving toward sustainability requires that we put our harvest, management, and monitoring components into an ecosystem context. On California's central coast, we are utilizing the Conservancy's “working landscape” experience and applying it to the ocean by collaborating with fishermen and regulatory agencies to improve the social–ecological systems that support the groundfish fishery. Reform of ailing fisheries requires new innovative models for collaboration among NGOs, regulatory agencies, and fishermen that are aimed at protecting ecosystems and the services they provide, including access to local, sustainable fishing opportunities (Gleason et al 2009). Existing fisheries management for the West Coast groundfish fishery is industry-dominated, conducted at a regional scale, and has largely failed both economically and ecologically. This is a fishery in crisis and in need of significant reform, particularly the bottom trawling component that dominates the fishery and can be historically characterized as a low-value (economically), high volume fishery with significant habitat disturbance, high bycatch rates, and high biomass extraction.
On the basis of recommendations from the National Research Council (2002) on abating bottom trawling impacts to seafloor habitats, we used private buyouts of federal trawl permits to leverage habitat protection (no-trawl zones established through an Essential Fish Habitat regulatory process), reduce trawl effort, and convert traditional trawl effort to more selective, less damaging gear types. We are improving resilience and sustainability by protecting additional seafloor habitat through private conservation agreements, promoting diversified harvest practices, improving monitoring, and fostering local stewardship. We are conducting the first controlled study of bottom trawling impacts and recovery of seafloor communities on the West Coast that aims to inform best practices for the trawling component of this fishery. By acquiring and assembling a trawl permit bank, the Conservancy is now able to lease its trawl permits to local fishermen with legal conservation restrictions, transition trawl effort to more selective and less destructive hook and line gear, and test collective harvesting and monitoring approaches. Together with partners we are also testing a prototype community-fishing association that could hold and manage permits or quotas and build a foundation for a more sustainable local fishery.
There is a growing consensus that a variety of management actions are needed to achieve both conservation and fishery objectives, and that there is no one solution for fisheries reform (Worm et al 2009). Increasing the resilience of social–ecological systems also depends upon finding ways for the local community to benefit from the enhanced productivity that results from conservation efforts and to provide diversified harvest approaches and opportunities whereby local fishermen can adapt to evolving regulatory measures, variable stock status, and changing climatic conditions. One challenge here is to identify appropriate environmental, economic and community goals and dynamic yet effective performance standards for this fishery. While we are currently using various metrics to assess project performance, such as fishing footprint, catch per unit effort, bycatch and discard rates, economic revenues, and jobs created, the line between sustainable and unsustainable use of the resource is dynamic and hard to define. Developing the frameworks for subregional-scale stock assessments and ecosystem modeling will be important tools to help address this challenge. With our partners, we are aiming for a triple bottom line: (a) provide the local fishing industry access to the resource and the ability to benefit from conservation and improved productivity; (b) promote harvesting means and methods that are sustainable, protect the health of the marine ecosystem, and reduce bycatch and discards; and (c) preserve the local fishing heritage, sustain the contributions of the fishing industry to the local communities, and promote fishermen as community stewards of marine resources.
Gleason, M , Cook, C. , Bell, M. , and Feller, E. . 2009. Are we missing the boat? Collaborative solutions for North American fish wars. Conservation Biology23: 1065–1067.
National Research Council (NRC)2002. Effects of trawling and dredging on seafloor habitat. National Academy Press, Washington, D.C., USA.
Worm, B. , Hilborn, R. , Baum, J. K. , Branch, T. A. , Collie, J. S. , Costello, C. , Fogarty, M. J. , Fulton, E. A. , Hutchings, J. A. , Jennings, S. , Jensen, O. P. , Lotze, H. K. , Mace, P. M. , McClanahan, T. R. , Minto, C. , Palumbi, S. R. , Parma, A. M. , Ricard, D. , Rosenberg, A. A. , Watson, R. , and Zeller, D. . 2009. Rebuilding global fisheries. Science325: 578–585.
Box 4. Sustainable Community-based Redwood Forests: the RFFI Model.
John Rogers, Redwood Forest Foundation, Inc., Mendocino, California 95460
The Redwood Forest Foundation, Inc. (RFFI, 〈www.rffi.org〉) promotes ecologically, economically, and socially responsible forestry as a means of sustaining the integrity of forest ecosystems and the human communities dependent upon them. In 2007 RFFI purchased the 50,000-acre Usal Redwood Forest. (Fig. 4-1)
RFFI's long-term stewardship goals for the Usal include rethinking forest management strategies to bring harvest and restoration practices into alignment with optimal biological productivity, ecosystem values, and community priorities.
The RFFI model recently achieved national recognition through Michael Fay, National Geographic Explorer in residence, who visited the property during his recent Redwood Transect. Mike's transect resulted in a cover story in National Geographic on the Redwood Region as a model, with global implications, for developing effective stewardship of forest resources.
There will always be more to learn about the interface between forest management and ecosystem functions, particularly in a world facing the potential of substantial climate change. Yet there are steps we can take today that we can be confident will improve ecosystem function and resilience, increase the long-term production of wood products for human use, and increase the economic sustainability of working forests. The key to implementing these practices is achieving an objective understanding of the true value, and the true cost, of providing various ecosystem services to society.
One important concept driving traditional forest management practices is the concept of “economic maturity” for forest stands, i.e., a rotation or harvest age that maximizes the present value of future harvests. These calculations typically do not include increases or decreases in viable habitat, carbon storage, water quality, or other ecosystem functions. Developing the resources necessary to steward working forests for multiple objectives, including nonmarket ecosystem services and community values, is a challenge. For example, how will we value the recovery and protection of salmon populations and Native American cultural heritage?
Effectively addressing these issues requires cooperation and understanding across a variety of disciplines, from ecologists and biologists to foresters and practitioners, from outside investors and policy-makers to local community members and leaders. RFFI's Usal forest provides an example of how rural communities can host these multidisciplinary conversations. Usal Redwood Forest offers an opportunity to test, evaluate, and implement an effective sustainable model of ecosystem stewardship.
Box 5. Planetary Stewardship and Coffee: A Case Study of the Dominican Republic.
Lee H. Gross, Graduate Student, Gund Institute for Ecological Economics, Rubenstein School of Environment and Natural Resources, University of Vermont.
The Pico Duarte Coffee Region and surrounding Madres de Las Aguas (Mother of Waters) Conservation Area are areas of critical ecological, economic, and social importance to the people of the Dominican Republic. In recent years much attention has been paid to the establishment of protected areas for the conservation of biodiversity and ecosystem services. (Parks in Peril Program 1997) Despite these efforts, protected areas represent less than 5% of this working agricultural landscape traditionally in shade coffee. Shade coffee polycultures have for three generations played an essential role in conserving water resources, providing habitat for birds, and providing consumptive resources to households. Farmers recognize the role of their shade coffee in maintaining these types of services, but have struggled to maintain their farms. As across much of the tropics, most Dominican coffee farmers are smallholders, managing only 1–3 hectares of land. Farmers generally depend on family members for labor, face a lack of access to land tenure, and live in constant poverty (ONAPLAN 2005). Falling coffee prices, trade liberalization, and rising input costs have made life more difficult for these small farmers (Taylor et al. 2008). Since 2002 these increased economic pressures have led to significant changes in the landscape. More than half of small coffee farms have agglomerated into larger farms of monoculture crops such as chayote squash and beans and pasture for cattle. These landscape changes have caused environmental degradation, threatening the ability of this working ecosystem to maintain natural functions and provide services at local, national, and international levels. In response, development organizations have attempted to combat these challenges by supporting small- to medium-sized enterprises that conserve natural resources through specialty coffee markets, eco-tourism and other forms of economic diversification. Unfortunately, these efforts have failed to change the current trajectory, driving the sustainability of the landscape and the livelihoods of its people down towards critical thresholds. Both water quality and the food security are threatened. A new approach is needed, one that integrates strategies to conserve ecosystem services and improve farmer livelihoods in agricultural landscapes.
From 2009 to 2010 a research project was carried out by University of Vermont researchers to examine the social and ecological processes that contribute to farmer household livelihoods. Baseline information on livelihoods, food security, and agroecological management was collected through household surveys, community focus groups and ecological sampling in 42 households in nine communities within the watershed. Preliminary findings show that smallholder farms under shade and organic management have higher levels of native tree and fruit species compared with those of larger producers. Farmers' abilities to maintain farm diversity are constrained by livelihood challenges in food security, and lack of financial capital, technical assistance, and education. Household data were integrated into higher levels of the decision-making process via local agricultural associations, companies purchasing coffee, and national and international development organizations to encourage greater environmental stewardship in a variety of ways:
A Participatory Action Research (PAR) framework was set up to develop a network between local farmer's associations, a Vermont coffee company, and University researchers, allowing them to work towards shared goals. PAR is dynamic; it requires a constant state of exchange, reflection, and action, facilitating a long-term relationship among stakeholders (Bacon et al. 2008).
Price Incentives were used to encourage best management practices. Previously farmers received little price premium for shade, organic, or other resource-conserving techniques that require additional labor. A deal was brokered between two farmers' associations and Vermont Coffee Company for significant increases in the amount of shade organic coffee purchased at an appropriate price to re-encourage production.
Transparent Reporting. As part of the coffee-purchasing agreement, a transparent reporting program is being developed to promote better understanding of the full costs to producers and consumers. Reporting will be available to stakeholders via monthly association meetings, annual stakeholder gatherings, and real time web-based software.
Increasing Information Flows. A capital-assets approach to household well-being is being integrated into both reporting programs and economic development planning (Bebbington 1999). Along with economic data, monitoring by researchers will track biophysical characteristics such as farm biodiversity and soil erosion (natural capital) as well as education, health, and job skills (human capital) employment and household income (financial capital), and infrastructure (built capital).
Diversification. More sources of income and consumption through agricultural diversification increase resilience of the landscape and livelihoods. Development strategies will focus on strengthening local farmers' markets, fruit tree nurseries, and eco-tourism operations to create more forms of off-farm employment, which decrease emigration to nearby cities.
Building Social Capital. A Dominican nonprofit was established to work with coffee growing communities and associations to address social needs in education, health, agricultural extension, and micro-finance. The foundation will receive its primary funding from a percentage of all coffee sold under this single-origin brand in addition to private philanthropy.
Ecosystem Services Modeling to target investments. The ARIES (Artificial Intelligence for Ecosystem Services) web application will be used to determine how shade coffee farms and other food production schemes provide critical sources and sinks of ecosystem services of value to humans across the landscape (Villa et al. 2009). This tool will equip companies, conservation organizations, and government agencies with the necessary information to make coordinated decisions that improve overall landscape functionality with minimum levels of investment.
In conclusion, this approach offers a blend of market and non-market approaches, informed by interdisciplinary science and a long-term commitment among stakeholders to shared goals. Recognizing the interconnection between sustainable livelihoods and ecosystems may help reverse the current trajectory nd enhance the resilience of the Pico Duarte region over the years to come.
Bacon, C. M. , Méndez, V. E. , and Fox, J. A. . 2008. Cultivating sustainable coffee: persistent paradoxes. Pages 337–372in Bacon, C. M. , Méndez, V. E. , Gliessman, S. R. , Goodman, D. , and Fox, J. A. , editors. Confronting the coffee crisis: Fair Trade, sustainable livelihoods and ecosystems in Mexico and Central America. MIT Press, Cambridge, Massachusetts, USA.
ONAPLAN (Oficina Nacional de Planificación)2005. Mapa de la Pobreza en la República Dominicana. Santo Domingo, Dominican Republic.
Parks in Peril Program1997. Initial site work plan. Parks in Peril. Madres de Las Aguas Conservation Area. Cordillera Central, Dominican Republic. United States Agency for International Development and The Nature Conservancy, Washington, D.C., USA.
Taylor, J. E. , Yunez-Naude, A. , Jesurun-Clements, N. , De los Santos, J. , Filipski, M. , and Paulino, J. . 2008. Posibles efectos de la liberalizacion comercial en los hogares rurales, a partir de un modelo desagregado para la economia rural, con enfasis en la probreza, el genero y la migracion. Inter-American Development Bank, Washingtron, D.C., USA.
Villa, F. , et al. 2009. ARIES (Artificial Intelligence for Ecosystem Services): a new tool for ecosystem services assessment, planning, and valuation. Proceedings of the 11th Annual BIOECON Conference on Economic Instruments to Enhance the Conservation and Sustainable Use of Biodiversity, Venice, Italy, September 2009. Fondazione Eni Enrico Mattei, Milan, Italy.
Box 6. Direct Trade Chocolate and the Quest for ”good to think, good to eat” Chocolate.
My lifelong love affair with chocolate has evolved as I have grown up and become aware that the food choices I make are choices about the world I want to live in (Nestle 2006). I want to know that the cacao in my chocolate bar is organic and grown using sustainable agricultural practices that do not contribute to tropical deforestation (Lopez 2002); that my chocolate was not made with child or slave labor (Onishi 2001); that the producers who grew my cacao were fairly paid and humanely treated (Tiffen 2002). I am not alone in this desire: many Americans today crave conscientiously produced chocolate.
Direct trade is a powerful response to this hunger for conscientiously produced chocolate. A business model that privileges a sustainable face-to-face relationship between cacao producers and manufacturers, direct trade works to make delicious chocolate by fairly compensating producers for growing organic cacao using sustainable agricultural methods. In this practice, producers in developing countries around the world are directly paid a premium over New York Board of Trade prices per ton of cacao to cultivate high-quality organic cacao (Taza Chocolate 2010). An extension of the notion of ethical trade (Barrientos 2000) and elaboration of Fair Trade (TransFair USA 2009), direct trade seeks to redress the problems perpetuated by the conventional chocolate commodity chain—where chocolate manufacturers do not take responsibility for the ecological and social costs of the cacao in their chocolate bars (Tiffen 2002). Whereas the conventional cacao commodity chain distances producers and manufacturers through numerous intermediaries (brokers, importers, exporters, etc.) to obscure the relationship between producer and manufacture, the practice of direct trade is built on a long-term, sustainable, close relationship between these two parties (see also Box 5). Within direct trade, the making of delicious chocolate becomes an equitable collaboration between producer and manufacturer.
While direct trade has yet to become a prevalent movement among the artisan chocolate-making community in the United States—only a few small chocolate manufacturers currently practice direct trade (Taza Chocolate 2010, Askinosie Chocolate 2010)—I hope to see this movement grow. Direct trade is an important step towards satisfying the desire for, in the words of Levi-Strauss (1962): “good to think, good to eat” chocolate.
Water shortages loom large in many regions of the world. The Columbia River may be one of the world's hardest-working rivers, harnessed on a massive scale to generate hydroelectric power and irrigate vast tracts of crops in arid lands, while still mandated to sustain a number of increasingly endangered wild salmon populations. Conflicts among these needs have led local stakeholders, tribes, scientists, and agency teams to intense negotiations in search of better information, collaboration, and regulatory models that effect more efficient use and distribution of precious, dwindling water supplies (Box 7). In Australia, water shortages are even more acute (Box 8). Australians live on one of the driest continents on Earth, and are presently facing the longest and most severe drought on record. Balancing regulation and market forces to cope with crises requires transparency and accurate reporting of “availability, right to take, and actual take of water.”
Box 7. Strategic Planning for Water Rights Acquisitions in the Columbia Basin: An Assessment of Regional Streamflow Response to Climate Change.
Erin Donley, College of Forest Resources, University of Washington, Box 352100, Seattle, WA 98195-2100 <email@example.com>
Robert J. Naiman, School of Aquatic and Fishery Sciences, University of Washington, Box 355020, Seattle, WA 98195-5020
Conflict over scarce water resources in the Columbia River Basin is historic and persistent. Trade-offs between in-stream and out-of-stream water use have become increasingly salient as the number of aquatic species listed under the Endangered Species Act continues to rise. Projected climate-induced reductions in stream-flow stand to further compound the complex issue. We introduce several conservation approaches that may reduce conflict, improve stewardship of scarce water resources, and ultimately improve the resilience of aquatic ecosystems in the Columbia River Basin:
Facilitate water right transactions and water marketing.
Employ scenario-based decision-support tools to identify directions for management and restoration.
Use the natural flow regime and environmental flows as foundational concepts to inform resilience-based natural resource management decisions.
Historically, the Columbia River Basin provided numerous water-ecosystem benefits through its natural flow regime. However, cumulative human impacts over the last century, including flow diversions for irrigation and hydroelectric dams, have drastically altered the natural flow regime. As a result of these and other factors, several aquatic organisms, including 12 Evolutionarily Significant Units (ESUs) of salmon, are listed under the Endangered Species Act as either threatened or endangered (McElhany et al. 2000). As of 2002, the National Oceanic and Atmospheric Administration (NOAA) and other federal agencies had collectively spent more than $4 billion in an attempt to support dwindling salmon populations (GAO 2002). To date, agency spending continues, but listed threatened and endangered salmonids of the Columbia Basin have not shown sustained improvement.
The reality that salmon populations continue to decline in spite of consistent federal funding underlines a persistent problem: an inefficient distribution of ecological and social goods. These paired goods are directly linked through our existing system of water rights allocation in the western United States. The ecological good, in this case, is the amount of water available in-stream; and the social good is the water right, the administrative document, that is associated with the available in-stream flow. Western water law, as it is currently practiced, provides incentive for out-of-stream water use, often to the detriment of struggling salmon populations (National Water Commission 1973). In sum, the existing distribution of water rights and reduced in-stream habitat represent substantial barriers to recovering listed salmonids.
In addition to problems associated with resource distribution, many climate scientists indicate that the Columbia Basin will experience major hydrologic changes in the near future. Specifically, climate change projections suggest that the timing and quantity of streamflow through certain sub-basins will change substantially due to reductions in snow pack in specific regions of the Cascade Mountains and other mountain ranges (Independent Scientific Advisory Board 2007).
Given that most salmonid populations are struggling under current hydrologic conditions, what can be done to address these compound resource distribution problems and improve the stewardship of the Columbia River Basin?
The following are social–ecological approaches that may foster improved resource distribution and strategic planning for salmonid habitat conservation in light of climate change in the Columbia River Basin.
Facilitate water right transactions and water markets in the Columbia River Basin
Recently, the National Fish and Wildlife Foundation, along with other nonprofit organizations, began reducing barriers to salmon habitat conservation by facilitating water right transactions on a willing-buyer, willing-seller basis in order to augment in-stream flows for listed salmonids in critical habitat areas. This market-based effort shows great promise for bolstering existing federal efforts, improving environmental outcomes for struggling fish populations, and reducing federal spending.
Employ scenario-based decision-support tools that include variance within ecosystem processes, management scenarios, and governance options
Decision-support tools, such as the use of scenario analysis with simulation models, can help in anticipating possible futures and stimulating novel approaches to conservation (Carpenter and Biggs 2009). We are currently using a multi-model approach that incorporates potential climate-induced changes in hydrology in selected sub-basins within the Columbia Basin, two agricultural water use scenarios, and two possible changes to the existing governance of in-stream flows. Ultimately, we will make recommendations to organizations within the water governance system in order to strategically prioritize future water rights transactions.
Use the natural flow regime and environmental flows as foundational concepts that inform resilience-based management decisions
Many scientists and policy makers identify managing for resilient freshwater ecosystems as a major challenge for the 21st century (Alcamo et al. 2008). In 2007, a group of international aquatic scientists and managers collectively drafted the Brisbane Declaration—a statement of scientific consensus that describes the imperative to incorporate ecosystem needs for freshwater into basin-wide and water-resource regional planning (Poff et al. 2010). Using the natural flow regime and environmental flows as foundational concepts to inform management can maximize the benefits of conservation, reinforce stewardship efforts and build resilience into natural ecosystem processes.
Alcamo, J. , Vörösmarty, C. , Naiman, R. J. , Lettenmaier, D. , and Pahl-Wostl, C. . 2008. A grand challenge for freshwater research: understanding the global water system. Environmental Research Letters3: 1–6.
Carpenter, S. , and Biggs, R. . 2009. Freshwaters: managing across scales in space and time. In Chapin, S., III , Kofinas, G. , and Folke, C. , editors. Principles of ecosystem stewardship: resilience-based natural resource management in a changing world. Springer, New York, New York, USA.
GAO (Government Accountability Office)2002. Columbia River salmon and steelhead: federal agencies' recovery responsibilities, expenditures and actions. Report to the Ranking Minority Member, Subcommittee on Fisheries, Wildlife, and Water, Committee on Environment and Public Works, U.S. Senate. GAO-02-612, Washington, D.C., USA.
Independent Scientific Advisory Board2007. Climate change impacts on Columbia River Basin fish and wildlife. ISAB Climate Change Report 2007-2, Northwest Power and Conservation Council, Portland, Oregon, USA.
McElhany, P. , Ruckelshaus, M. H. , Ford, M. J. , Wainwright, T. C. , and Bjorkstedt, E. P. . 2000. Viable salmonid populations and the recovery of evolutionarily significant units. NOAA Technical Memorandum NMFS-NWFSC-42, U.S. Department of Commerce, Washington, D.C., USA.
National Water Commission1973. Water policies for the future: final report to the President and to the Congress. U.S. Government Printing Office, Washington, D.C., USA.
Poff, N. L. , et al. 2010. The ecological limits of hydrologic alteration (ELOHA): a new framework for developing regional environmental flow standards. Freshwater Biology55: 147–170.
Box 8. Water Stewardship: An Australian Perspective
Dr Renée Kidson, National Water Account Unit, Australian Government Bureau of Meteorology and Center for Integrated Water Research, University of California Santa Cruz and Professor Brent Haddad, Center for Integrated Water Research, University of California Santa Cruz
Environmental stewardship theory holds that crises can be valuable catalysts for transformation to a more sustainable trajectory (Chapin et al. 2010). This is certainly the case for water management in Australia. The first decade of the new century has been characterized by the longest, most severe drought of record (Bureau of Meteorology: 〈http://www.bom.gov.au〉), which has affected the reliability of water supplies for both urban and rural communities (Murray-Darling Basin Authority: 〈http://www.mdba.gov.au/〉) and industries. In Australia, one of the driest continents on Earth, water shortages are not a new phenomenon. What is different about the current drought has been the response to shortage, and the evidence of a growing awareness of, and willingness to apply, environmental stewardship ideas in practice.
During historical water shortages, the main long-term solutions were to build more storage (dams) or undertake inter-basin transfers. However, under Australia's water reform agenda4, there is now broad recognition that surface and groundwater systems have been over-allocated for human use, at significant environmental cost. While dams, bores and pipelines will continue to form an important component of water supply in Australia, building new dams is increasingly untenable due to environment impacts. In Queensland in 2009, plans for the construction of a major new dam (the Traveston project) were rejected on the grounds of environmental impact on iconic species including the Australian lungfish, the Mary River turtle and the Mary River cod (Ministerial press release: Traveston Dam gets final no 〈http://www.environment.gov.au/minister/garrett/2009/mr20091202a.html〉). With traditional water supply options constrained, the current drought in Australia has seen the convergence of several environmental stewardship factors (Chapin et al. 2010) that provide more sustainable options to achieve supply-demand balance:
2. Engage an informed public in the decision-making process. This includes providing the public with information to enable a meaningful debate. Government processes in Australia involve extensive community consultation and transparent procedures in policy development. Most cities now have ongoing public education programs for water. In the development of Sydney's Metropolitan Water Plan 2006 (〈http://www.waterforlife.nsw.gov.au/about/plan〉), the option to raise the dam level and increase inter-basin transfers from the Shoalhaven River was shelved partially due to community feedback regarding environmental consequences (Shoalhaven River water supply transfers and environmental flows. Community information documents: 〈http://www.sca.nsw.gov.au/publications/publications/123〉), despite being the cheapest option to boost supply.
3. Reduce per capita consumption. Environmental stewardship theory advocates responsible use of natural resources and a mindfulness of the natural renewal rate relative to the consumption rate (Chapin et al. 2010). With regulatory support, major investment in water efficiency programs and a public willing to change their attitudes and behaviors toward water use (Head and Muir 2007), Australian cities have been able to significantly reduce per capita water consumption (Water Conservation and Recycling Report 〈http://www.sydneywater.com.au/Water4Life/WhatSydneyWaterIsDoing/Initiatives.cfm〉). This highlights an emerging value system that recognizes stewardship principles and is willing to forego consumption (Randolph and Troy 2008) in the interests of both the environment and other users. Reduced per capita demand can defer the need for supply augmentation, and enables a larger population to be serviced from the same finite range of sources.
4. Planetary stewardship: minimize carbon emissions. Inter-basin transfers, recycling, and desalination all have one thing in common: relative to gravity-fed dam water, all of these sources involve considerable energy consumption. Australia's water crisis converged with growing global awareness of the impacts of carbon emissions from fossil fuel energy generation. Emissions from the portfolios of new supply options can be mitigated by sourcing renewable energy. For example, Sydney made a commitment to power its desalination plant with 100% renewable energy, and purchased a wind farm to enable this (Sydney Water Corporation: 〈http://www.sydneywater.com.au/Water4Life/Desalination/renewableenergy.cfm〉).
6. Transparent Reporting. Accurate quantification and reporting of both supply and demand of water is essential in making the best use of a scarce water resource. A crucial component of Australia's water reform agenda is to facilitate better measurement, metering, and monitoring of water resources, and to report in a regular, transparent, and consistent way. The Commonwealth Water Act (2007) includes a requirement to publish a National Water Account for Australia, which reports the availability, rights to take, and actual take of water (Pilot National Water Account 〈http://www.bom.gov.au/water/nwa/〉; Water Accounting Standards Board 〈http://www.bom.gov.au/water/wasb/〉).
In summary, the current drought in Australia has provided an opportunity for new solutions to water scarcity to emerge. This has taken place against an historical backdrop of over-reliance on and over-use of traditional water supplies, and in consideration of future climate change and population growth (Warner 2009). The new solutions reflect a growing commitment to water stewardship in Australia, and reflect a value system that places high importance on minimizing environmental impacts while accommodating future growth. The expression of these stewardship principles has been enabled by technological developments and governance mechanisms that permit alternative water supplies such as desalination and recycling to be developed, while making the most efficient use of existing supplies. Water reform in Australia seeks to harmonize environmental stewardship with economic principles to achieve a sustainable water future.
The views expressed in this article are the personal views of the authors, and do not represent the official position of the Australian Government.
Chapin, F. S. , et al. 2010. Ecosystem stewardship: sustainability strategies for a rapidly changing planet. Trends in Ecology and Evolution25 ( 4): 241–249.
These crises, and efforts to avert crises through stewardship, point toward our need for ways to trace material fluxes (of water, carbon, organisms, toxins) to document, interpret, and predict their space–time dynamics and trajectories into the future. “Isoscapes” are presented as powerful tools for mapping, understanding, and managing the human-driven and natural processes controlling the fluxes that affect our futures (Box 9). Mapping the future of the Mississippi Gulf Coast offers a path toward sustainable stewardship by revealing sites where, if sufficient river sediment can be diverted to sustain recovery of wetland vegetation, vertical accretion, and land building in the form of shoreline deltas and barrier islands would follow (Box 10). The energy technologies that replace fossil fuel will have large, and still perhaps largely unforeseen, effects on our planetary stewardship efforts. It is important that we scrutinize trade-offs between efficiencies and side effects of the two main alternative solar energy conversion technologies: photovoltaic and solar thermal. These trade-offs, including water costs and toxic issues, are summarized in Box 11.
Box 9. Understanding and Monitoring Interconnectedness and System-wide Changes with Isoscapes.
Jason West, Texas A&M University, and Todd Dawson, University of California, Berkeley
Human impacts have left their mark on Earth so significantly that some have called the current geologic epoch the “Anthropocene” (e.g., Crutzen 2002). It is almost certain that all biogeochemical cycles on Earth bear the imprint of human activity. We know humans have altered key processes in water, carbon, and nitrogen cycling (chapters in Dawson and Siegwolf 2007). Although humanity is changing many components of the biosphere, critical uncertainties remain, especially when assessing whether a given activity is sustainable. New tools are needed to understand and monitor ecological processes as Earth's climate changes, human populations expand, and technology continues to enhance humanity's ability to alter our environment. Stable isotope ratios of the biotic and abiotic components of the earth system record and trace a wide range of physical, chemical, and biological processes. Recent work has demonstrated in a wide range of fields that there are often coherent spatiotemporal patterns that reflect these processes and can therefore be used to study these processes at a range of spatial and temporal scales (West et al. 2010). These isoscapes represent powerful tools for understanding and managing the spatially and temporally varying processes central to ecological sustainability. (An “isoscape” is a representation of the spatiotemporal isotopic variation in a particular system (typically a map), and can be based on interpolation of spatially distributed observations, a product of process-based modeling, or direct observation.)
A relevant example is provided by global plant and soil nitrogen isoscapes published by Amundson et al. (2003). Here the authors argued that the observed spatial variation could, in part, represent ecosystem sensitivity to nitrogen deposition. If this is the case, nitrogen isoscapes could allow us to identify and monitor potentially sensitive ecosystems at a range of scales, identifying thresholds and indicating when intervention may be necessary before more drastic changes ensue (e.g., forest decline or increased stream nitrate loading). Significant work is still needed to understand nitrogen isotopes in a variety of biological systems. Specific efforts must be made to study the drivers of spatiotemporal variation at multiple scales. Insights from isoscapes are also found in other major biogeochemical cycles on Earth.
Water isoscapes are proving to be critically important in understanding regional and global water cycles. Also, because hydrogen and oxygen atoms from water are incorporated into the organic molecules of organisms, water isocapes become key tools for understanding a wide range of ecological and human social dynamics (chapters in West et al. 2010). These encompass insights into changing patterns of animal movements, resource use, and the social–ecological system that is the global food market, and the movement of products around the planet satisfying a range of demands.
Since isoscapes are geographical depictions of natural processes, they can also serve important communication roles. Scientists and nonscientists intuitively understand spatial patterns, especially when they recognize the underlying geography. As such, when isoscapes depict potential threats to social-ecological sustainability (like regional vulnerabilities to drought or nitrogen loading), they serve to communicate the science for effective management and even policy changes. Continued development of isoscapes as tools for understanding the interconnections among human activity, ongoing environmental change, and the ecological processes on which life depends is needed and should be fueled by the need for interdisciplinary work on integrated ecological–social systems.
Amundson, R. , Austin, A. T. , Schuur, E. A. G. , Yoo, K. , Matzek, V. , Kendall, C. , Uebersax, A. , Brenner, D. , and Baisden, W. T. . 2003. Global patterns of the isotopic composition of soil and plant nitrogen. Global Biogeochemical Cycles17( 1): 1031. [doi:10.1029/2002GB001903]
Dawson, T. E. , and Siegwolf, R. T. W. , editors. 2007. Stable isotopes as indicators of ecological change. Academic Press, San Diego, California, USA.
West, J. , Bowen, G. , Dawson, T. , and Tu, K. , editors. 2010. Isoscapes: Understanding movement, pattern, and process on Earth through isotope mapping. Springer, Dordrecht, The Netherlands.
Box 10. Adapting Coastal Resources of the Mississippi River Delta to a Changing Climate: Multipurpose Conflicts of River Basin Management.
Robert R. Twilley, Department of Oceanography and Coastal Sciences, Louisiana State University
The Mississippi River basin and its delta convey water, sediment, and chemicals from 3.4 million km2, (draining 31 U.S. states and two Canadian provinces) to the Gulf of Mexico. The Mississippi is the 4th largest river system in the world in terms of drainage area, and the 7th largest in terms of discharge and sediment load. Problems associated with this system, and with most deltas around the world, require policies that span catchments and coasts (Blum and Roberts 2009, Twilley and Rivera-Monroy 2009). The challenges facing this river basin and its delta reflect a national inability to come to grips with the need to deal with neglected infrastructure, both natural and built, despite the realization that both provide security to coastal communities and to the nation (Galloway et al. 2009).
The sustainability of coastal Louisiana is critical to the nation (Day et al. 2007). It will not be possible to protect and restore coastal Louisiana, however, without significant changes in the way federal and state governments resolve conflicts of navigation and flood control with protection of our coastal natural resources. Our dire circumstances have recently been highlighted in both scientific literature and regional media (Twilley and Rivera-Monroy 2009): sediments from the Mississippi River basin, particularly from the Missouri, are trapped behind dams, halving our historical sediment load. Even the sediment that makes it past Baton Rouge bypasses our coastal wetlands in leveed channels, and is lost to the deep waters of the Gulf of Mexico. Without harvesting those sediments to sustain the geologic framework of this region, the ecological resources cannot survive, and the coast will continue to retreat as wetlands become open water 〈http://www.clear.lsu.edu/〉. Coastal restoration and hurricane protection for coastal communities grow even more challenging under the specter of climate change and sea level rise (Fig. 1, Fig. 2, Fig. 3).
Vulnerability of ecosystems to climate change depends not only on the magnitude of physical change over time, but also on how well an ecosystem can adapt to those changes. Adaptation by the Mississippi River delta, the capacity of coastal landscapes to be self-sustaining in the face of reduced sediment and increased sea level, requires aggressive management of the Mississippi River and its regional sediment supply. First, we need to arm the delta with the resources it needs to adapt, specifically, sediments delivered to coastal wetlands. Second, while we must acknowledge that under present circumstances the historical landscape footprint cannot be restored (we cannot expect to recover the entire coast to a condition that many grandparents remember), we can build a smarter coastal footprint to help preserve industrial, urban, and economic activities that sustain critical services to the nation. Smarter approaches to expanding our economic base in the coastal zone will require more concentrated assets and more resilient ways of deriving our livelihoods.
Rethinking how we manage the Mississippi River, not only to provide navigation and flood control, but also to divert critical sediments to where they are needed to stabilize Louisiana's degrading wetlands, will require a plan for long-term rehabilitation (e.g. 100-year project cycle). Along with flood control, we have to design for control floods. After the 1927 flood, Congress passed the Flood Control Act of 1928, which created the comprehensive Mississippi River and Tributaries (MR&T) project. This permitted the commission to deal with the lower River valley as a whole: one mission, one entity, working cooperatively with all interested parties to integrate the resources needed to meet the challenge. Congress needs to rethink authority of river basins not only for flood control and navigation, but also for the restoration of floodplains and deltaic coasts. The delta is highly vulnerable to the present mismanagement of the river resources, and its erosion will be exacerbated by a changing climate. It is urgent that we move beyond the paralysis of conflicting federal policies and develop large-scale, bold agendas supporting aggressive restoration actions..
The adaptation of the Mississippi River delta is in our hands, collectively, as a society. We are the culprit responsible for its decline; it is our obligation to meet the challenge of its restoration head-on with the same commitment and dedication that we have given in the past to flood control and navigation.
Blum, M. D. , and Roberts, H. H. . 2009. Drowning of the Mississippi Delta due to insufficient sediment supply and global sea-level rise. Nature Geoscience2: 488–491.
Twilley, R. R. , and Rivera-Monroy, V. H. . 2009. Sediment and nutrient tradeoffs in restoring Mississippi River Delta: restoration vs eutrophication. Journal of Contemporary Water Research and Education141: 1–6.
Box. 11. Two Paths Towards Solar Energy: Photovoltaic vs. Solar Thermal.
Emily C. Warmann, Department of Mechanical Engineering, California Institute of Technology and G. Darrel Jenerette, Department of Botany and Plant Sciences, University of California Riverside
The capture and conversion of solar energy to electricity offers a potential long-term and low-cost source of sustainable power for society. At present and for the foreseeable future, the two main technologies of solar energy conversion are photovoltaics, which use light-matter interactions, and concentrated solar thermal, which first converts light energy to heat which generally drives a steam turbine to generate electricity. Photovoltaic systems currently available have 10–20% energy efficiencies and produce power at a median cost of $0.24/kwh, with efficiencies of experimental technologies as high as 41% (Ginley et al. 2008, Evans et al. 2009). Concentrated solar thermal installations currently have efficiencies of up to 30% and produce power at a cost of $0.10/kW (Mehos 2008).
The chief drawback of solar energy production is the inability to generate power at night and consequent needs for energy storage. Other challenges associated with the broad deployment of solar are associated with the space requirements, water requirements, and material life cycles. To supply sufficient solar power for Los Angeles, CA, which uses approximately 140 billion kWh per year of electricity, through utility scale installations would require approximately 150,000 hectares for photovoltaic and 100,000 hectares for concentrated solar thermal based on present efficiencies. If constructed in open space this area requirement would have large consequences for ecosystem functioning and species habitat. In contrast to concentrated solar thermal, photovoltaics are well suited for distributed power generation. Small-scale photovoltaics can be deployed on existing infrastructure such as warehouses, retail stores, and houses, which greatly decreases footprint requirements with the added benefit of reduced transmission requirements. For Los Angeles, assuming 20% of the urban area is covered by roofing and only 10% of this area is suitable for photovoltaics at current efficiencies, solar could supply 80% percent of the annual energy requirements (LA County Solar Map: 〈lacounty.solarmap.org〉). Many of the locations with high potential for solar energy are in regions with low precipitation and the water requirements for solar energy are not inconsequential. Photovoltaics use 1/8th the water per kWh that solar thermal consumes (Evans et al. 2009). Solar thermal using steam generation consumes water at the location of energy production, while for photovoltaics water is primarily required at manufacturing sites with some on-going water requirements for washing. Again for Los Angeles, photovoltaics would require 1.1 million acre-ft and solar thermal 8.6 million acre-ft of water annually, using existing technologies. Life cycle challenges for photovoltaics are associated with the general need for rare earth elements and toxins associated with all semi-conductor manufacturing processes.
To realize the potential of solar power will require further technological improvements in efficiency, cost, and storage. Both technologies present large up-front capital costs with minimal ongoing expenses, and consequently benefit from institutional support for financing installations. Ensuring that regulation and market economics do not inhibit deployment of solar on existing urban infrastructure are important policy challenges.
Evans, A. , Strezov, V. , and Evans, T. J. . 2009. Assessment of sustainability indicators for renewable energy technologies. Renewable and Sustainable Energy Reviews13: 1082–1088.
For now on a personal note, it was a very positive experience for us to compile these “boxes” about how the contributors are engaging in planetary stewardship in diverse ways, over a wide array of scales and social–ecological systems. Literally, no one we asked to write up their effort refused! None were too busy to share their visions and the lessons so far learned from their efforts. As we continue our exchange of information about steps and missteps toward becoming better Earth stewards, one useful focus would be how groups assess whether the system is responding positively or negatively to particular stewardship efforts—because of the time lags, cross-scale linkages, and nonlinearities of social ecological systems, we know that recognizing and evaluating their trajectories can be challenging.
Questions that came up during our forum and in previous discussions (e.g., in Chapin et al. 2010, and in discussions at the ESA Millennium Conference on Water Ecosystem Services, Drought, and Social Justice in Athens Georgia, November 2009) include:
What scales of processes tip social ecological systems between sustainable and nonsustainable trajectories? (e.g., if a truck collection service helps local organic farmers distribute their produce to several farmer's markets, what are the scales (distance traveled, numbers of trucks, etc.) over which this service enhances social–ecological resilience? How might these scales change with context (e.g., in the trucking example, as energy costs or sources change)?
Under what circumstances can long-distance connections foster, rather than undermine, local resilience and sustainability?
Within social–ecological systems, which individuals, species, institutions, or parts of the landscape are most vulnerable to various environmental stressors? Which are most resilient? What characteristics or factors affect this?
What combinations of stressors (e.g., drought plus water extraction from rivers) lead to abrupt, nonlinear shifts in systems?
What science gaps impede our ability to reconfigure or manage various social ecological systems for resilience and sustainability?
There may be better questions. Most of us discover inductively, from examples. We hope that this ESA Bulletin article and its 11 case histories inspire additional perspectives that will add to our knowledge of the various paths towards planetary stewardship that collectively could lead us toward a renewed and sustainable relationship with our planet's working and natural ecosystems.