Browsing Gund Institute for Ecological Economics by Issue Date

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Browsing Gund Institute for Ecological Economics by Issue Date

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  • Luce, C. H.; Wemple, B. C. (Earth Surface Processes and Landforms, 2001
  • Farley, J.; Costanza, R. (Ecological Economics, 2002
      Economics has been defined as the science of allocation of scarce resources towards alternative ends. This definition implies that the first step in economic analysis is to determine what ends are desirable for society. Most sectors of the society would agree that sustainability is a desirable end, but there is little agreement as to what a sustainable future would look like. The University of Maryland Institute for Ecological Economics sponsored a democratic future search process designed to create a relatively detailed, shared vision of a sustainable and desirable USA in the year 2100. This paper presents the vision developed at that conference, examines the resources required to achieve the vision, and assesses the suitability of market mechanisms for allocating the required resources towards the desired ends. We find that markets are not efficient mechanisms for allocation in this case, and propose the institutions of a 'strong democracy' as a promising alternative. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Gustafson, S.; Wang, D. (2002
      This study examined the effects of agricultural runoff on the vegetation structure of Franklin Bog, a priority conservation area located in a rapidly developing region of northwestern Vermont. Forested and agricultural runoff from the mixed land use watershed created differential vegetation patterns in the wetland, including weedy species introductions. Concentrations of nitro-en and phosphorus were measured in the stream runoff from four forested subwatersheds and two agricultural subwatersheds. Nutrient concentrations were significantly higher for agricultural vs. forested runoff for all measured parameters. Nitrate-and total phosphorus concentrations in agricultural runoff ranged from 0.62 to 1.35 mg L-1 and 0.07 to 0.37 mg L-1, respectively Forested runoff values were less than 0.37 mg L-1 nitrate and 0.09 mg L-1 total phosphorus. Significantly higher proportions of weedy species occurred at impacted vs. reference sites (46 +/- 5%, vs. 23 +/- 4%). Furthermore, significantly higher total percent vegetated cover occurred at impacted vs. reference sites (116 +/- 11% vs. 77 +/- 9%) suggesting nutrient induced plant growth. Of the nine frequently occurring species categorized as bog species' only one was found within impacted sites while all nine were found at the reference sites. This suggests that the wetland's distinctive native flora is being replaced by widespread, vigorous species enhanced by agricultural nonpoint pollution in the watershed of Franklin Bog. Protection of wetlands requires attention to conservation measures throughout the entire watershed.
  • Blecker, Robert A; Seguino, Stephanie (Review of Development Economics, 2002
  • Bormann, B. T.; Keller, C. K.; Wang, D.; Bormann, F. H. (Ecosystems, 2002
      In their review of 24 studies of forest nitrogen (N) budgets, Binkley and others (2000) found that only one of them supported the conclusion that an N accumulation of more than 25 kg N ha(-1) y(-1) is possible without known symbiotic N-2-fixing plants. They contended that, given how well the N cycle is known, new N accumulation pathways are unlikely. They also concluded that the Hubbard Brook sandbox study (Bormann and others 1993) was insufficiently replicated and had low precision in vegetation and soil estimates. Here we reevaluate and extend the sandbox analysis and place the findings in a broader context. Using multiple methods of estimating vegetation N accumulation in pine sandboxes, we arrived at results that differed from the reported rates but still strongly supported large biomass N accumulation. The original study's conclusions about soil N changes were strengthened when new evidence showed that N accumulated in lower horizons and that the sandboxes were successfully homogenized at the beginning of the experiment. Unexplained ecosystem N accumulation ranged from about 40 to 150 kg ha(-1) y(-1), with 95% confidence intervals that did not include zero. No evidence was found that could balance the sandbox ecosystem N budgets without adding unexplained N. Unreplicated experiments, such as the sandboxes, can explore the possibility that N can accumulate in ways not explainable by mass balance analysis, but they cannot quantify the frequency and extent of the phenomenon. New studies should combine substantive microbiological, mass balance, and process research using multiple direct measures of N-2 fixation.
  • Ricketts, T. H.; Daily, G. C.; Ehrlich, P. R. (Biological Conservation, 2002
      Indicator taxa are often proposed as efficient ways of identifying conservation priorities, but the correlation between putative indicators and other taxa has not been adequately tested. We examined whether a popular indicator taxon. the butterflies, could provide a useful surrogate measure of diversity in a closely related but relatively poorly known group, the moths, at a local scale relevant to many conservation decisions (10(0)-10(1) km(2)). We sampled butterflies and moths at 19 sites representing the three major terrestrial habitats in sub-alpine Colorado: meadows. aspen forests, and conifer forests. We found no correlation between moth and butterfly diversity across the 19 sites, using any of five different diversity measures. Correlations across only meadow sites (to test for correlation within a single, species-rich habitat) were also not significant. Butterflies were restricted largely to meadows, where their host plants occur and thermal environment is favorable. In contrast, all three habitats contained substantial moth diversity, and several moth species were restricted to each habitat. These findings suggest that (1) butterflies are unlikely to be useful indicators of moth diversity at a local scale; (2) phylogenetic relatedness is not a reliable criterion for selecting appropriate indicator taxa, and (3) a habitat-based approach would more effectively conserve moth diversity in this landscape and may be preferable in many situations where indicator taxa relationships are untested. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • Franklin, J. F.; Spies, T. A.; Van Pelt, R.; Carey, A. B.; Thornburgh, D. A.; Berg, D. R.; Lindenmayer, D. B.; Harmon, M. E.; Keeton, W. S.; Shaw, D. C.; Bible, K.; Chen, J. Q. (Forest Ecology and Management, 2002
      Forest managers need a comprehensive scientific understanding of natural stand development processes when designing silvicultural systems that integrate ecological and economic objectives, including a better appreciation of the nature of disturbance regimes and the biological legacies, such as live trees, snags, and logs, that they leave behind. Most conceptual forest development models do not incorporate current knowledge of the: (1) complexity of structures (including spatial patterns) and developmental processes; (2) duration of development in long-lived forests; (3) complex spatial patterns of stands that develop in later stages of seres; and particularly (4) the role of disturbances in creating structural legacies that become key elements of the post-disturbance stands, We elaborate on existing models for stand structural development using natural stand development of the Douglas-fir-western hemlock sere in the Pacific Northwest as our primary example; most of the principles are broadly applicable while some processes (e.g. role of epicormic branches) are related to specific species. We discuss the use of principles from disturbance ecology and natural stand development to create silvicultural approaches that are more aligned with natural processes. Such approaches provide for a greater abundance of standing dead and down wood and large old trees, perhaps reducing short-term commercial productivity but ultimately enhancing wildlife habitat, biodiversity, and ecosystem function, including soil protection and nutrient retention. (C) 2002 Elsevier Science B.V All rights reserved.
  • Boumans, R.; Costanza, R.; Farley, J.; Wilson, M. A.; Portela, R.; Rotmans, J.; Villa, F.; Grasso, M. (Ecological Economics, 2002
      A global unified metamodel of the biosphere (GUMBO) was developed to simulate the integrated earth system and assess the dynamics and values of ecosystem services. It is a 'metamodel' in that it represents a synthesis and a simplification of several existing dynamic global models in both the natural and social sciences at an intermediate level of complexity. The current version of the model contains 234 state variables, 930 variables total, and 1715 parameters. GUMBO is the first global model to include the dynamic feedbacks among human technology, economic production and welfare, and ecosystem goods and services within the dynamic earth system. GUMBO includes modules to simulate carbon, water, and nutrient fluxes through the Atmosphere, Lithosphere, Hydrosphere, and Biosphere of the global system. Social and economic dynamics are simulated within the Anthroposphere. GUMBO links these five spheres across eleven biomes, which together encompass the entire surface of the planet. The dynamics of eleven major ecosystem goods and services for each of the biomes are simulated and evaluated. Historical calibrations from 1900 to 2000 for 14 key variables for which quantitative time-series data was available produced an average R-2 of 0.922. A range of future scenarios representing different assumptions about future technological change, investment strategies and other factors have been simulated. The relative value of ecosystem services in terms of their contribution to supporting both conventional economic production and human well-being more broadly defined were estimated under each scenario, and preliminary conclusions drawn. The value of global ecosystem services was estimated to be about 4.5 times the value of Gross World Product (GWP) in the year 2000 using this approach. The model can be downloaded and run on the average PC to allow users to explore for themselves the complex dynamics of the system and the full range of policy assumptions and scenarios. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Seguino, S. (Pacific Review, 2002
      This paper examines the gender distribution of the benefits of economic growth in several Asian economies from 1970-90. Using Borda rank ordering, we compare the progress made in these countries towards closing the gender gap in well-being. In addition to commonly-used indicators, trends in the ratio of females to males in the population are examined. We explore determinants of changes in this ratio, using regression analysis. The results indicate that gender equity in quality-of-life ratings is highest in those Asian economies that grew the slowest over the period in question. Further, the data indicate that economic growth does not have a significant effect on the female-to-male population ratios for this set of countries. Variables that affect women's bargaining power do, however, have a positive effect on relative female life chances, as does spending on public education.
  • Danks, C. (Ford Foundation, New York.New York, 2002
  • Noordewier, T.; Vermont. Dept. of Tourism and Marketing.,; University of Vermont. School of Business Administration.,; University of Vermont. Vermont Tourism Data Center., (Vermont Tourism Data Center, Burlington, VT.Burlington, VT, 2002
  • Erickson, J. D.; Gowdy, J. M. (Bioscience, 2002
  • Danks, C. (IUCN, Gland.Gland, 2002
  • Herendeen, R. A.; Wildermuth, T. (Ecological Economics, 2002
      We develop three quantitative indicators of the physical/biological aspect of sustainability. They are based on depletion of resources, dependence on outside subsidies, and disruption of natural cycles. We apply the indicators to an agricultural county in Kansas, using energy, water, soil, and nitrogen as numeraires. 9/10 of Chase County is dedicated to range beef cattle grazing and 1/10 to row-cropping and confinement animal feeding. Range production is relatively non-depleting, independent, and non-disrupting. Cropping is more depleting, dependent, and disrupting, but comparable with that in other agricultural areas. We discuss how this pattern, mediated by absentee land-holding and low human population density, trades off against economic income. With the exception of energy, all analyses are only in terms of direct flows (e.g. actual amounts crossing the county boundary). For energy, we also estimate the energy consumed elsewhere to produce imported non-energy goods and services. (C) 2002 Elsevier Science B,V. All rights reserved.
  • Roman, J. (Harvard University, Cambridge, U.K.., 2003
  • Ricketts, T.; Imhoff, M. (2003
      Urbanization and agriculture are two of the most important threats to biodiversity worldwide. The intensities of these land-use phenomena, however, as well as levels of biodiversity itself, differ widely among regions. Thus, there is a need to develop a quick but rigorous method of identifying where high levels of human threats and biodiversity coincide. These areas are clear priorities for biodiversity conservation. In this study, we combine distribution data for eight major plant and animal taxa (comprising over 20,000 species) with remotely sensed measures of urban and agricultural land use to assess conservation priorities among 76 terrestrial ecoregions in North America. We combine the species data into overall indices of richness and endemism. We then plot each of these indices against the percent cover of urban and agricultural land in each ecoregion, resulting in four separate comparisons. For each comparison, ecoregions that fall above the 66th quantile on both axes are identified as priorities for conservation. These analyses yield four "priority sets" of 6-16 ecoregions (8-21% of the total number) where high levels of biodiversity and human land use coincide. These ecoregions tend to be concentrated in the southeastern United States, California, and, to a lesser extent, the Atlantic coast, southern Texas, and the U.S. Midwest. Importantly, several ecoregions are members of more than one priority set and two ecoregions are members of all four sets. Across all 76 ecoregions, urban cover is positively correlated with both species richness and endemism. Conservation efforts in densely populated areas therefore may be equally important (if not more so) as preserving remote parks in relatively pristine regions.
  • Herendeen, R. A. (Frontiers in Ecology and the Environment, 2003

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