Papers by Daniel Campbell
Environmental Monitoring and Assessment, 2018
To address increasing demand, bean producers have intensified agricultural activities by increasi... more To address increasing demand, bean producers have intensified agricultural activities by increasing application of industrial inputs. Such intensification can impose environmental risks to vulnerable ecosystems. Emergy and economic analyses were utilized in this study to investigate and comparison of environmental performance of five management patterns specified by differing degrees of intensification, i.e., ecologic, integrated, low-, medium-and high-input production systems at Bean Research Station in Khorram Dasht, Iran. The total emergy supporting these systems was estimated to be 6.52E+15, 1.22E+16, 6.62E+15, 1.10E+16 and 1.54E+16 sej ha −1 for the ecologic, integrated, low-, medium-and high-input systems, respectively. The purchased emergy inputs accounted for the largest portion of the total emergy inputs to these systems and ranged between 60.84 and 75.80%. The renewable fractions, transformities, emergy yield ratios, environmental loading ratios, emergy sustainability indices, and the economic output to input ratios demonstrate that the ecologic and low-input systems performed well compared to the three more industrial systems when considering their environmental sustainability. However, the more industrial systems had comparatively higher economic output. Generally, the results illustrate that sustainable bean production will depend on the transition from fossil fuel intensive systems to more natural resource intensive ones. To achieve more sustainable systems, applying conservation tillage and replacing chemical fertilizer with organic fertilizer are advocated for use in bean
Ecological Indicators, 2001
A benthic index of estuarine condition was constructed for the Virginian Biogeographic Province (... more A benthic index of estuarine condition was constructed for the Virginian Biogeographic Province (from Cape Cod, Massachusetts, to the mouth of Chesapeake Bay, Virginia) with data collected during summers of 1990 through 1993 by the US EPA's Environmental Monitoring and Assessment Program (EMAP). Forty-eight metrics, based on attributes of the macrobenthos, were considered for the index, including measures of biodiversity, community condition, individual health, functional organization, and taxonomic composition. Salinity was correlated significantly with some of the metrics. Therefore, some metrics were normalized for salinity. The data used to develop the index (the calibration data) included equal numbers of reference and degraded sites, distributed equally across three salinity zones (<5, 5-18, >18‰). An independent set of data was used for validation. Linear discriminant analysis identified combinations of metrics that could best discriminate reference from degraded sites. The targets for correct classification were 90% of the sites for the calibration data and 80% for the validation data. Six combinations of metrics were identified. The final index was based on the ecological interpretation and relevance of the individual metrics and the ability to meet the calibration and validation targets. The final index consisted of three metrics: a positive contribution from salinity-normalized Gleason's D (a biodiversity metric), and negative contributions from two taxonomic composition metrics, abundances of spionid polychaetes and of salinity-normalized tubificid oligochaetes. The index correctly classified 87% of reference and 90% of degraded sites in the calibration data and 88% of reference and 81% of degraded sites in the validation data. The index correctly classified sites over the full range of salinity (tidal-fresh to marine waters) and across grain sizes (silt-clay to sand).
Ecological Engineering, Apr 1, 2009
The emergy signature of the earth has changed dramatically over the past 250 years as a result of... more The emergy signature of the earth has changed dramatically over the past 250 years as a result of the development of technologies to use fossil fuels for human purposes. This change has resulted in the self-organization of modern industrial societies and their concomitant processes now dominate the earth. One such process is the transport of species from specific regions of the Earth, to which they were formerly confined, and their introduction to new territories. In this paper, we examine the role of exotic Spartina sp. in promoting the self-organization of coastal ecosystems for maximum empower on three coasts, Marlborough Sounds, NZ, Willapa Bay, WA, USA and Jiangsu Province, PRC. We found evidence to support the hypothesis that Spartina marsh maximizes empower through the building of new land in coastal environments that are dominated by an excess of sediment. Where excess sediments are present as a consequence of past geologic processes, and where a low marsh plant was absent, Spartina has been seen as an interloper to be destroyed. There is some evidence that given sufficient time, exotic Spartina marshes may increase productivity and diversity in these coastal systems, as well as those that are actively prograding.
Ecological Engineering, Aug 1, 2014
Biological Conservation, Oct 1, 2007
Evaluating the ecological and economic benefits of nature reserves in a fair way is a difficult p... more Evaluating the ecological and economic benefits of nature reserves in a fair way is a difficult problem confronting not only conservation scientists and managers but also governments and private land owners. Nature reserves and other social and economic land uses must ...
Energy, Aug 1, 2019
： ： ： ：An emergy-based index system was proposed to handle the incomparability problem that occur... more ： ： ： ：An emergy-based index system was proposed to handle the incomparability problem that occurs when quantities of different kinds must be compared in decision-making. Our results indicate that China's energy security improved over the last five decades from resource availability, resource affordability, economic efficiency, and environmental impacts perspectives. After quality adjusting of the energy it consumes, China was not yet the largest energy consumer in the world before 2016, with the emergy of its primary energy consumption increased to 99.68% that of the U.S. in 2015. The emissions of CH 4 had the largest environmental impact, followed by SO 2 and N 2 O, while the CO 2 emissions is one order of magnitude lower. Speeding up the development and utilization of domestic coal bed methane (CBM) as an energy source will improve the quality and diversity of China's primary energy mix, as well as reduce CH 4 emissions. China benefited from its energy imports, which accounted for about 5% of GDP over the past two decades. Increasing the fraction and diversity of coal imports can further improve the benefit ratio of energy imports to China. The emergy indices proposed here are general and can be applied to evaluate the energy security of other national systems.
Renewable & Sustainable Energy Reviews, Feb 1, 2016
The long-term dynamic changes in the triad, energy consumption, economic development, and Greenho... more The long-term dynamic changes in the triad, energy consumption, economic development, and Greenhouse gas (GHG) emissions, in Japan after World War II were quantified, and the interactions among them were analyzed based on an integrated suite of energy, emergy and economic indices. The results quantitatively showed that two different energy strategy periods, one before 1973 using new sources of higher quality energy and one after 1973 focused on improving the efficiency of energy generation methods, could explain the linear increase in national economic development in Japan over the 66 years from 1946 to 2011. Japan benefited both ecologically and economically from importing fossil fuels, which accounted for 8.7% of the nominal GDP of Japan averaged over the entire study period. The total environmental impacts of GHG (i.e., CO 2 , CH 4 and N 2 O) emissions measured by emergy decreased after 1997, and since 2009 they have remained lower than 76% of the emissions in 1990, even though no decrease in the global warming impact based on the weight of CO 2 was observed. Emergy methods and Energy Systems models revealed aspects of the complicated interactions among energy consumption, economic development, and the potential environmental impact of GHG emissions which formerly had not been recognized.
The timing of winter-spring phytoplankton blooms in temperate and high latitudes varies by as muc... more The timing of winter-spring phytoplankton blooms in temperate and high latitudes varies by as much as 6 weeks among years, being tied closely to the amount of solar insolation received. One effect of this variation is that water temperature and its effect on the matabolic rate of pelagic and benthic consumers will vary accordingly. We have constructed a simulation model based on 15 years of data on water temperatures and solar insolation not only to predict the timing of the winter-spring plankton bloom in coastal waters near Boothbay Harbor, Maine, but to investigate the various processes that are important in carbon flow through the ecosystem. The model has shown that variable bloom timing results in blooms occurring over a range of relatively cold water temperatures (ca. -1 to 5[degrees]C) and that the water temperature during and following the bloom is of paramount importance to the partitioning of the primary production into higher pelagic and benthic trophic levels. Blooms occurring in waters at or near 0[degrees]C may be accompanied by very low metabolism of both pelagic and benthic consumers. These results could have significant implications for how we view oceanographic processes ranging from fisheries production to the global carbon cycle.
Social Science Research Network, 2021
Clean Technologies and Environmental Policy
Renewable and Sustainable Energy Reviews
Journal of Cleaner Production
Ocean & Coastal Management
Encyclopedia of Natural Resources: Land, 2014
Throughout history, small geographic areas have been united either by conquest or negotiation. Th... more Throughout history, small geographic areas have been united either by conquest or negotiation. The central determining factor has been the supplies of available energy that could be used for creating the initial organization and for maintaining it against depreciation or conquest. The contemporary Middle East and North Africa consists of many nation states that may be too small for long-term individual viability, but perhaps offering the potential for a regional union, because of the large oil and gas reserves that exist in some of these countries. In particular, the present conflict between the people of Israel and the people of Palestine has deep historical roots grounded in the differences in ethnicity, religious beliefs and customs, as well as, a conflict of the hopes and dreams that these two peoples hold for a single small geographic area. The possibility of a United States of Abraham, analogous to the United States of America or the European Union, is examined as a democratic...
There is a growing realization within the scientific community and in the public at large that th... more There is a growing realization within the scientific community and in the public at large that the environment makes real contributions to wealth that are not adequately valued by markets. In addition, almost everyone recognizes when they are getting a “good deal” on a purchase. In some people,this perception may be elicited by the fact that there is a surplus of real wealth (emergy) obtained in the consumption of an item. In other words, the real wealth in the item was purchased at a price less than that which the consumer would have paid, if the free work of nature had been included in the price. We hypothesize that there is “surplus value” in products taken from the environment and that it can be quantified through emergy accounting. Emergy quantifies real wealth or the amount of quality-adjusted work that is required to create an item and that the item can do when it is used for its intended purpose. Emergy evaluation allows us to attribute a fair and objective value to both the...
Journal of Applied Phycology, 2021
Journal of Cleaner Production, 2021
Abstract In addition to achieving of food security in the long-run, the identification and introd... more Abstract In addition to achieving of food security in the long-run, the identification and introduction of sustainable ecosystems is associated with the protection of natural resources and the provision of environmental services that flow from those resources. A paradigm for the production of shallots has arisen in the agroecosystems of Iran to prevent the extinction of the shallot plant, on one hand, and to meet the market demand for this valuable medicinal-industrial product, on the other. This study aimed to identify the most sustainable shallot production system by comparing mechanized, traditional, and conservation shallot production systems with the growth of this plant in its natural habitat in Selseleh County, Iran, during 2018–2019. The analysis was done by calculating net emergy of each system and by reviewing 14 different emergy indices. Soil conservation is very important in the sustainability of agroecosystems. In this regard, a positive evaluation of the energy input structures in a conservation system is based on the soil stability of that system. The results showed that the status of a protected system is optimal based on the values of the Unit Emergy Value (UEV = 6.62E+05 sej J−1), Specific emergy (SE = 7.05E+09 sej g−1), Inverse emergy exchange ratio (IEER = 0.942), and Emergy index of product safety (EIPS = 1) indices and, to some extent, on Renewable emergy ratio (R%), Modified version of the environmental sustainability index (ESI∗), Modified version of the environmental loading ratio (ELR∗), and Emergy invested per $ net profit (EINPR). As a result, the most optimal system was found by increasing the amount of the free environmental renewable input flow (R). The optimal EINPR, Economic emergy efficiency (EEE) and IEER values of the natural habitat indicate the risk of overharvesting shallots from this system, which necessitates paying more attention to protecting the ecosystem and preventing overharvesting. Although a number of indices showed the advantage of the mechanized shallot production system over the other two agroecosystems. However, since an important part of the desirability of a mode of production implied by these indices is related to the share of free environmental inputs that are used in a renewable manner, modes of production that rely heavily on the non-renewable use of free environmental flows and result in soil instability are not preferred, thus a mechanized system is not recommended as the first choice for shallot production. The equality of the EIPS index both in conservation and in natural systems showed the high quality of the crop in the conservation system among the studied crop systems.
Ecological Modelling, 2020
The use of emergy to evaluate the sustainability of greenhouse systems leads to management recomm... more The use of emergy to evaluate the sustainability of greenhouse systems leads to management recommendations to increase the sustainability of production in these systems. In this study, four greenhouse systems for cucumber, tomato, bell pepper, and eggplant production, located in Jiroft city, Iran, were evaluated using emergy sustainability indices. To accomplish this study, 56, 31, 19, and 12 greenhouses were selected for cucumber, tomato, bell pepper, and eggplant production, respectively. Analysis of twelve emergy indices and a study of the social characteristics of the producers using Analytic Hierarchy Analysis showed that the sustainability of the cucumber production system was greater than that of the other three systems. The calculated unit emergy values for economic yield (UEV E) generally indicated that greenhouse systems were at least 100 times more sustainable than open farm systems for the production of different products, primarily because of drastically reduced soil erosion. The highest (5.10E+04 sej J −1 [4.96E+04, 5.25E+04]) and lowest (7.27E+03 sej J −1 [7.09E+03, 7.45E+03]) UEV E values were calculated for the bell pepper and cucumber systems, respectively. Also, cucumber producers had greenhouses with larger areas compared to the greenhouses used for the other crops examined in this study. The physiological characteristics of cucumber plants resulted in greater sustainability of this system, because the plants were able to capture more of the free renewable energy, had a higher production potential, and this production system made more efficient use of the workforce. In contrast, the highest proportion of purchased non-renewable resources reduced the sustainability of the eggplant production system compared to the other systems studied. Therefore, selection of a plant with more potential to use free local environmental energy, higher yield, and more efficient use of labor will lead to greater sustainability of greenhouse vegetable production systems. Sustainability can also be increased by paying attention to the sociotechnical characteristics of the producers, the use of technologies to reduce non-renewable inputs to the greenhouse building, and by reducing the proportion of non-renewable inputs used overall.
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Papers by Daniel Campbell