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Daniel E. Campbell

Bio: Daniel E. Campbell is an academic researcher from University of Rhode Island. The author has contributed to research in topics: Emergy & Sustainability. The author has an hindex of 30, co-authored 86 publications receiving 2731 citations. Previous affiliations of Daniel E. Campbell include Chinese Academy of Sciences & United States Environmental Protection Agency.


Papers
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Journal ArticleDOI
TL;DR: The concept of emergy defined as the available energy (or exergy) of one form used up directly and indirectly to produce an item or action (Odum, Environmental Accounting Emergy and Environmental Decision Making, John Wiley & Sons, Inc., 1996) requires the specification of a uniform solar equivalent exergy reference.

227 citations

Journal ArticleDOI
01 May 1994
TL;DR: In this paper, the authors use biological simulation modelling as a tool for the analysis of spring plankton blooms in shallow, coastal waters in temperate latitudes of the North Atlantic, and show that interannual variability in bloom initiation arises from year-to-year differences in incident irradiation, as determined by weather.
Abstract: Established conceptual models of the initiation and progression of spring phytoplankton blooms are reconsidered in light of recent observations We use biological simulation modelling as a tool for the analysis of spring plankton blooms in shallow, coastal waters in temperate latitudes of the North Atlantic The model shows that interannual variability in the timing of bloom initiation arises from year-to-year differences in incident irradiation, as determined by weather (cloudiness) This variability in timing results in some years when the spring bloom occurs in cold water temperatures near 0°C Model results suggest that due to low temperature inhibition of heterotrophic consumption, more fresh organic material is delivered to the benthos in these cold-water blooms than when the bloom occurs in waters only 3°C warmer Thus we suggest that variable bloom timing can be important to the trophodynamic fate of bloom products We suggest that variability in timing of spring phytoplankton blooms in offshore and open ocean waters is also related to weather, through controls on the light field and wind mixing Our analyses of wind-driven vertical mixing demonstrate such blooms can begin following the winter period of deep convection, and prior to the vernal development of stratification, provided that wind speed is below a certain, predictable threshold, which we estimate In such cases, there may be several spring bloom pulses, each interrupted by self-shading light limitation or vertical mixing events Eventually the seasonal thermocline develops and nutrient exhaustion curtails bloom production This means that the spring phytoplankton bloom in offshore and open ocean areas may be significantly more productive, result in more export production, and be more important to the carbon cycle, than has been previously assumed Furthermore, these features of temperate marine planktonic ecosystems are not only sensitive to annual variations in weather, but also any trends that might result from greenhouse warming or other factors that affect the climate system

226 citations

Book ChapterDOI
TL;DR: In this article, the human carrying capacity for a region at a specified standard of living depends on the economic and environmental resources of the region and the exchange of resources across regional boundaries.
Abstract: The human carrying capacity for a region at a specified standard of living depends on the economic and environmental resources of the region and the exchange of resources across regional boundaries. The length of time that a human population living at a given standard can be sustained depends on the rates of use and renewal of the resource base. All environmental, economic, and social resources are produced as a result of energy transformations; therefore, the energy required for their production can be specified and evaluated in common terms by converting their energy values into emergy. Emergy is defined as the available energy of one kind, previously used up directly and indirectly to make a product or service. Its unit is the emjoule. Emergy values and indices are used to evaluate the resource base for Maine, a politically defined region, and to estimate its human carrying capacity at the 1980 standard of living and for possible future resource bases. Emergy indices for Maine are compared with similar indices for Florida, Texas, and the United States to demonstrate variations in human carrying capacity and sustainability among different regions. The 1980 standard of living for Maine, Florida, Texas, and the Nation as measured by emergy use per person fell within a relatively narrow range of 3.4E16 to 4.3E16 solar emjoules y-1. The human carrying capacity for a region is considered within a pulsing paradigm for sustainabilty and within the constraints provided by a renewable resource base. For example, in the short-term the developed human carrying capacity for Maine is largely determined by the fuel emergy inflow relative to renewable emergy resources. If purchased emergy inflows relative to Maine’s renewable emergy increase to the average ratio for a developed country around 1980, the population living in Maine at 1980 standards could increase to 2.9 million or 2.6 times Maine’s 1980 population. In contrast, the human carrying capacity based on Maine’s renewable resources alone was 0.37 million people at the 1980 standard of living or 33% of the 1980 population.

144 citations

Journal ArticleDOI
TL;DR: A combined evaluation of these agricultural production systems was done using emergy, energy and economic methods, and both energy and emergy evaluations showed that long-term rice was the best choice for sustainable development, followed by rotation systems.

121 citations

Journal ArticleDOI
TL;DR: In this article, the authors examined the oil refining processes in Italy and the United States to estimate the transformity and specific emergies of petroleum derivatives, based on their assumptions that petroleum derivatives are splits of a complex hydrocarbon mixture and that the emergy is split based on the fraction of energy in a product.

120 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors explore the social dimension that enables adaptive ecosystem-based management, focusing on experiences of adaptive governance of social-ecological systems during periods of abrupt change and investigates social sources of renewal and reorganization.
Abstract: ▪ Abstract We explore the social dimension that enables adaptive ecosystem-based management. The review concentrates on experiences of adaptive governance of social-ecological systems during periods of abrupt change (crisis) and investigates social sources of renewal and reorganization. Such governance connects individuals, organizations, agencies, and institutions at multiple organizational levels. Key persons provide leadership, trust, vision, meaning, and they help transform management organizations toward a learning environment. Adaptive governance systems often self-organize as social networks with teams and actor groups that draw on various knowledge systems and experiences for the development of a common understanding and policies. The emergence of “bridging organizations” seem to lower the costs of collaboration and conflict resolution, and enabling legislation and governmental policies can support self-organization while framing creativity for adaptive comanagement efforts. A resilient social-eco...

4,495 citations

Journal ArticleDOI
TL;DR: It is proposed that the self-organizing process of adaptive comanagement development, facilitated by rules and incentives of higher levels, has the potential to expand desirable stability domains of a region and make social–ecological systems more robust to change.
Abstract: Ecosystems are complex adaptive systems that require flexible governance with the ability to respond to environmental feedback. We present, through examples from Sweden and Canada, the development of adaptive comanagement systems, showing how local groups self-organize, learn, and actively adapt to and shape change with social networks that connect institutions and organizations across levels and scales and that facilitate information flows. The development took place through a sequence of responses to environmental events that widened the scope of local management from a particular issue or resource to a broad set of issues related to ecosystem processes across scales and from individual actors, to group of actors to multiple-actor processes. The results suggest that the institutional and organizational landscapes should be approached as carefully as the ecological in order to clarify features that contribute to the resilience of social-ecological systems. These include the following: vision, leadership, and trust; enabling legislation that creates social space for ecosystem management; funds for responding to environmental change and for remedial action; capacity for monitoring and responding to environmental feedback; information flow through social networks; the combination of various sources of information and knowledge; and sense-making and arenas of collaborative learning for ecosystem management. We propose that the self-organizing process of adaptive comanagement development, facilitated by rules and incentives of higher levels, has the potential to expand desirable stability domains of a region and make social-ecological systems more robust to change.

1,705 citations

Journal ArticleDOI
TL;DR: Elton's "The Ecology of Invasions by Animals and Plants" as mentioned in this paper is one of the most cited books on invasion biology, and it provides an accessible, engaging introduction to the most important environmental crises of our time.
Abstract: Much as Rachel Carson's \"Silent Spring\" was a call to action against the pesticides that were devastating bird populations, Charles S. Elton's classic \"The Ecology of Invasions by Animals and Plants\" sounded an early warning about an environmental catastrophe that has become all too familiar today-the invasion of nonnative species. From kudzu to zebra mussels to Asian long-horned beetles, nonnative species are colonizing new habitats around the world at an alarming rate thanks to accidental and intentional human intervention. One of the leading causes of extinctions of native animals and plants, invasive species also wreak severe economic havoc, causing $79 billion worth of damage in the United States alone. Elton explains the devastating effects that invasive species can have on local ecosystems in clear, concise language and with numerous examples. The first book on invasion biology, and still the most cited, Elton's masterpiece provides an accessible, engaging introduction to one of the most important environmental crises of our time. Charles S. Elton was one of the founders of ecology, who also established and led Oxford University's Bureau of Animal Population. His work has influenced generations of ecologists and zoologists, and his publications remain central to the literature in modern biology. \"History has caught up with Charles Elton's foresight, and \"The Ecology of Invasions\" can now be seen as one of the central scientific books of our century.\"-David Quammen, from the Foreword to \"Killer Algae: The True Tale of a Biological Invasion\

1,321 citations

Journal ArticleDOI
01 Feb 2014-Energy
TL;DR: In this paper, the authors provide a comprehensive and critical overview of the latest models and assessment techniques that are currently available to analyze MES and in particular DMG systems, including for instance energy hubs, microgrids, and VPPs (virtual power plants), as well as various approaches and criteria for energy, environmental, and technoeconomic assessment.

1,060 citations

Journal ArticleDOI
TL;DR: The use of ecological indicators has been widely accepted by scientists, environmental managers, and the general public as mentioned in this paper, and they have been used to assess the condition of the environment, as early warning signals of ecological problems, and as barometers for trends in ecological resources.
Abstract: ▪ Abstract Ecological indicators have widespread appeal to scientists, environmental managers, and the general public. Indicators have long been used to detect changes in nature, but the scientific maturation in indicator development primarily has occurred in the past 40 years. Currently, indicators are mainly used to assess the condition of the environment, as early-warning signals of ecological problems, and as barometers for trends in ecological resources. Use of ecological indicators requires clearly stated objectives; the recognition of spatial and tempor al scales; assessments of statistical variability, precision, and accuracy; linkages with specific stressors; and coupling with economic and social indicators. Legislatively mandated use of ecological indicators occurs in many countries worldwide and is included in international accords. As scientific advancements and innovation in the development and use of ecological indicators continue through applications of molecular biology, computer technolog...

772 citations