Browsing CTL Experiments by Issue Date

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Browsing CTL Experiments by Issue Date

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  • Balmford, A.; Bruner, A.; Cooper, P.; Costanza, R.; Farber, S.; Green, R. E.; Jenkins, M.; Jefferiss, P.; Jessamy, V.; Madden, J.; Munro, K.; Myers, N.; Naeem, S.; Paavola, J.; Rayment, M.; Rosendo, S.; Roughgarden, J.; Trumper, K.; Turner, R. K. (Science, 2002
      On the eve of the World Summit on Sustainable Development, it is timely to assess progress over the 10 years since its predecessor in Rio de Janeiro. Loss and degradation of remaining natural habitats has continued largely unabated. However, evidence has been accumulating that such systems generate marked economic benefits, which the available data suggest exceed those obtained from continued habitat conversion. We estimate that the overall benefit:cost ratio of an effective global program for the conservation of remaining wild nature is at least 100:1.
  • Noordewier, Tom; Vermont. Dept. of Tourism and Marketing.,; University of Vermont. School of Business Administration.,; University of Vermont. Vermont Tourism Data Center., (2002
  • Ali, S. H. (Canadian Review of Sociology and Anthropology-Revue Canadienne De Sociologie Et D AnthropologieCan Rev Soc Anthrop, 2002
      A social construction perspective is applied in the analysis of the risk management controversies that arose in response to a large toxic fire that occurred at a Hamilton, Ontario plastics recycling facility. By focussing on the claimsmaking processes involved in the interaction of government officials, environmental movement actors, technical experts, and residents, it was found that an overly narrow focus on technical matters led to the exclusion of lay concerns based on cultural rationality, thereby resulting in a very contentious and divisive setting for interaction. Implications of the empirical findings for the risk society thesis and risk communication theory are explored.
  • Gustafson, S.; Wang, D. (Journal of Environmental Quality, 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.
  • Moulaert, A.; Mueller, J. P.; Villarreal, M.; Piedra, R.; Villalobos, L. (Agroforestry Systems, 2002
      A silvopastoral model that combines the production of pasture herbage with valuable native timber species has potential to simultaneously address the multiple goals of reforestation, conservation of native species and enterprise intensification. The objective of this study was to design, establish and monitor early growth of a silvopastoral experiment on a dairy farm in the north Atlantic zone of Costa Rica. Two indigenous timber species, Vochysia guatemalensis and Hyeronima alchorneoides were planted with and without the tropical pasture legume, Arachis pintoi in a split plot design, (2 x 2) factorial arrangement of treatments with four replications. After the first two years, V. guatemalensis was significantly taller (3.1 m) than H. alchorneoides (2.5 m). The mean root collar diameter for V. guatemalensis was significantly larger (6.5 cm) than H. alchorneoides (4.5 cm). Two-year establishment was acceptable for the tree component (83 to 85% survival) but poor for A. pintoi (2 to 8% of the sward). The most important pest affecting the establishment of the timber species was the leaf cutter ant, Atta cephalotes. An insect larvae, Cosmopterix sp., severely damaged 39% of the V. guatemalensis trees by repeatedly attacking their apical meristems. The two-year establishment data was insufficient to accurately predict future wood volume. A hypothetical economic analysis concluded that the silvopastoral system must average at least 1.2 m(3) wood volume/paddock/year (20 m(3)/ha/year) throughout the first ten years of growth to assure a positive economic return from timber. The experiment is planned for a ten year period, which corresponds to the estimated rotation length for harvesting the timber species.
  • Villa, F.; Tunesi, L.; Agardy, T. (Conservation Biology, 2002
      As the role of marine protected areas as conservation tools becomes better understood and more sophisticated, their planning becomes more complicated. Systematic, objective approaches to site selection and design can help reconcile conflicting interests, represent stakeholders' viewpoints fairly and evenly, and extend the scope of planning studies from single reserves to networks. We illustrate the use of spatial multiple-criteria analysis for determining the suitability, of marine areas for different uses and levels of protection. This technique couples geographic information systems (GIS)for land assessment and evaluation with a formal statement of the design priorities as seen from the different viewpoints of all involved stakeholders. The planning process, while staying focused on the main purposes of conservation and feasibility, involves all the main interest groups in the definition of priorities so that conflicts and tensions are kept tinder control We used multiple-criteria analysis to integrate objective data with the contrasting priorities of different stakeholders in the planning of a marine protected area. The results of the analysis can be used to define all optimal spatial arrangement of different protection levels, As a case study we developed a zoning plan for one of the first marine protected areas in Italy, the Asinara Island National Marine Reserve.
  • Costanza, R.; Voinov, A.; Boumans, R.; Maxwell, T.; Villa, F.; Wainger, L.; Voinov, H. (Ecological Monographs, 2002
      Understanding the way regional landscapes operate. evolve, and change is a key area of research for ecosystem science. It is also essential to support the "place-based" management approach being advocated by the U.S. Environmental Protection Agency and other management agencies. We developed a spatially explicit, process-based model of the 2352 km(2) Patuxent River watershed in Maryland to integrate data and knowledge over several spatial, temporal, and complexity scales. and to serve as an aid to regional management. In particular. the model addresses the effects of both the magnitude and spatial patterns of human settlements and agricultural practices on hydrology, plant productivity. and nutrient cycling in the landscape. The spatial resolution is variable, with a maximum of 200 X 200 m to allow adequate depiction of the pattern of ecosystems and human settlement on the landscape. The temporal resolution is different for various components of the model. ranging from hourly time steps in the hydrologic sector to yearly time steps in the economic land-use transition module. We used a modular. multiscale approach to calibrate and test the model. Model results show good agreement with data for several components of the model at several scales. A range of scenarios with the calibrated model shows the implications of past and alternative future land-use patterns and policies. We analyzed 18 scenarios including: (1) historical land-use in 1650, 1850, 1950, 1972, 1990, and 1997; (2) a "buildout" scenario based on fully developing all the land currently zoned for development: (3) four future development patterns based on an empirical economic land-use conversion model; (4) agricultural "best management practices" that lower fertilizer applications (5) four "replacement" scenarios of land-use change to analyze the relative contributions of agriculture and urban land uses; and (6) two "clustering" scenarios with significantly more and less clustered residential development than the current pattern. Results indicate the complex nature of the landscape response and the need for spatially explicit modeling.
  • 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.
  • Erickson, J. D.; Gowdy, J. M. (Bioscience, 2002
  • Limburg, K. E.; O'Neill, R. V.; Costanza, R.; Farber, S. (Ecological Economics, 2002
      Ecological and economic systems are undeniably complex. Whereas a goal of delineating 'ecosystem services' is to make readily apparent some of the important ways in which ecosystems underpin human welfare, insights are also gained by appreciating the nonlinear dynamic properties of ecosystems. In this paper, we review some of the relevant characteristics of complex systems. Ecosystems and economic systems share many properties, but valuation has typically been driven by short-term human preferences. Here we argue that as the force of humanity increases on the planet, ecosystem service valuation will need to switch from choosing among resources to valuing the avoidance of catastrophic ecosystem change. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Costanza, R. (Ecological Economics, 2002
  • 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.
  • 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.
  • Ali, S. H. (Social ProblemsSoc Probl, 2002
      The case of a large toxic fire occurring at the Plastimet plastics recycling facility in Hamilton, Ontario is used as an empirical referent to investigate the structural origins involved in the incubation of a technological disaster Hamilton is known as the "recycling center of Canada," and this paper examines the role of the broader socio-historical forces that led to this development and then relates this to the general issue of how specialized communities with a narrow economic base may become particularly vulnerable to the onset of technological disasters. As such, a political economy of place is developed to help understand how historically based regulatory, industrial, political, economic and social processes may interact in a complex manner to produce devastating results. Specifically, this paper identifies and discusses several particularly important features involved in disaster incubation, including: (i) a lax regulatory and enforcement framework related to land use, as well as, building and property codes at the local level; (h) a legal loophole in the regulatory policy that governs materials recycling; (iii) the market dynamics of materials recycling; (A,) the transformation of spatial fix; and most notably, (v) the deviant industrial practice of "sham recycling."
  • Villa, F.; Wilson, M. A.; de Groot, R.; Farber, S.; Costanza, R.; Boumans, R. M. J. (Ecological Economics, 2002
      Quantifying the value of ecosystem services is important for the social recognition and acceptance of ecosystem management across multiple geographic scales. Yet, the data required to perform such quantifications and the dynamic models that allow the projection of policy changes into the future are currently scattered, incomplete, and difficult to use. We describe the design of the Ecosystem Services Database (ESD), an integrated, web-accessible knowledge base that links a relational database for temporally and spatially explicit data to dynamic simulation models. The ESD architecture supports unit standardization, scale translation in space and time, and statistical analysis. Process-based dynamic models and valuation methods can be run by end users either through a web-based simulation engine or on their own computers by means of open-source software. The knowledge base will serve as: (1) a communication tool for use by researchers in several fields; (2) an analytical tool for meta-analysis, synthesis, and prediction; (3) an educational tool to disseminate knowledge on ecosystem services and their valuation; (4) a collaborative tool for institutions involved in different aspects of ecosystem service valuation; and (5) a prototype for linking databases and dynamic models. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Sutton, P. C.; Costanza, R. (Ecological Economics, 2002
      We estimated global marketed and non-marketed economic value front two classified satellite images with global coverage at 1 km(2) resolution. GDP (a measure of marketed economic output) is correlated with the amount of light energy (LE) emitted by that nation as measured by nighttime satellite images. LE emitted is more spatially explicit than whole country GDP, may (for some nations or regions) be a more accurate indicator of economic activity than GDP itself, can be directly observed, and can be easily updated on an annual basis. As far as we know, this is the first global map of estimated economic activity produced at this high spatial resolution (1 km(2)). Ecosystem services product (ESP) is an important type of non-marketed value. ESP at 1 km(2) resolution was estimated using the IGBP land-cover dataset and unit ecosystem service values estimated by Costanza et al. [Valuing Ecosystem Services with Efficiency, Fairness and Sustainability as Goals. Nature's Services, Island Press, Washington DC, pp. 49-70]. The sum of these two (GDP + ESP) = SEP is a measure of the subtotal ecological-economic product (marketed plus a significant portion of the non-marketed). The ratio: (ESP/SEP) x 100 = (%ESP is a measure of proportion of the SEP from ecosystem services. Both SEP and %ESP were calculated and mapped for each 1 km(2) pixel on the earth's surface, and aggregated by country. Results show the detailed spatial patterns of GDP, ESP, and SEP (also available at: http://www.du.edu/ similar to psutton/esiindexisee/EcolEconESI.htm). Globally, while GDP is concentrated in the northern industrialized countries, ESP is concentrated in tropical regions and in wetlands and other coastal systems. (X)ESP ranges from 1% for Belgium and Luxembourg to 3% for the Netherlands, 18% for India, 22% for the United States, 49% for Costa Rica, 57% for Chile, 73% for Brazil, and 92% for Russia. While GDP per capita has the usual northern industrialized countries at the top of the list, SEP per capita shows a quite different picture, with a mixture of countries with either high GDP/capita, high ESP/capita, or a combination near the top of the list. Finally, we compare our results with two other indices: (1) The 2001 Environmental Sustainabilily Index (ESI) derived as an initiative of the Global Leaders of Tomorrow Environment Task Force, World Economic Foruin, and (2) Ecological Footprints of Nations: How much Nature do they use? How much Nature do they have? developed by Mathis Wackernagel and others. While both of these indices purport to measure sustainability, the ESI is actually mainly a measure of economic activity (and is correlated with GDP), while the Eco-Footprint index is a measure of environmental impact. The related eco-deficit (national ecological capacity minus national footprint) correlates well with %ESP. (C) 2002 Elsevier Science B.V. All rights reserved.
  • 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.
  • Villa, F.; McLeod, H. (Environmental Management, 2002
      Environmental decision-making and policy-making at all levels refers necessarily to synthetic, approximate quantification of environmental properties such as vulnerability, conservation status, and ability to recover after perturbation. Knowledge of such properties is essential to informed decision-making, but their definition is controversial and their precise characterization requires investments in research, modeling, and data collection that are only possible in the most developed countries. Environmental agencies and governments worldwide have increasingly requested numerical quantification or semi quantitative ranking of such attributes at the ecosystem, landscape, and country level. We do not have a theory to guide their calculation, in general or specific con-texts, particularly with the amount of resources usually available in such cases. As a result, these measures are often calculated with little scientific justification and high subjectivity, and such doubtful approximations are used for critical decision-making. This problem applies particularly to countries with weak economies, such as small island states, where the most precious environmental resources are often concentrated. This paper discusses frameworks for a "least disappointing," approximate quantification of environmental vulnerability. After a review of recent research and recent attempts to quantify environmental vulnerability, we discuss models and theoretical frameworks for obtaining an approximate, standardizable vulnerability indicator of minimal subjectivity and maximum generality. We also discuss issues of empirical testing and comparability between indicators developed for different environments, To assess the state of the art, we describe an independent ongoing project developed in the South Pacific area and aimed to the comparative evaluation of the vulnerability of arbitrary countries.

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