347 research outputs found

    A finite element approach to open channel flow

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    A dissipative Galerkin scheme has been developed for the study of the propagation of hydraulic jumps and bores in open channels. It uses the basis function to weight the temporal terms and an asymmetric weighting function to weight the convection terms. The scheme has been improved with routines that both apply the asymmetric weighting function only in the region of the shock and proportion the use of the asymmetric weighting function according to the magnitude of the local spurious oscillations. The introduced variability in the model improved the performance of the model in all examples tested. This scheme was compared to a Galerkin scheme with a symmetric weighting function instead of the basis function weighting the temporal terms and without the improved routines for applying the weighting functions. The scheme with the routines for proportionally applying the spatial weighting functions compared favorably

    Scientific instruments for climate change adaptation: estimating and optimizing the efficiency of ecosystem service provision

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    Adaptation to the consequences of climate change can depend on efficient use of ecosystem services (ES), i.e. a better use of natural services through management of the way in which they are delivered to society. While much discussion focuses on reducing consumption and increasing production of services, a lack of scientific instruments has so far prevented other mechanisms to improve ecosystem services efficiency from being addressed systematically as an adaptation strategy. This paper describes new methodologies for assessing ecosystem services and quantifying their values to humans, highlighting the role of ecosystem service flow analysis in optimizing the efficiency of ES provision.Ecosystem services, flow analysis, Bayesian modeling, spatial analysis, Environmental Economics and Policy, Q01, Q54, Q55, Q57,

    Ecological Economic Applications for Urban and Regional Sustainability

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    Urban and regional development decisions have long-term, often irreversible impacts on the natural and built environment. These changes impact society’s wellbeing, yet rarely occur in the context of well understood economic costs and benefits. The cumulative effects of these individually small land use decisions are also very large. Ecological economics provides several frameworks that could inform more sustainable development patterns and practices, including ecosystem service valuation (ESV) and the Genuine Progress Indicator (GPI). This dissertation consists of a series of articles addressing urban and regional development from an ecological economic perspective, using GPI, ESV, and evaluation of tax and subsidy programs. The GPI has been well developed at the national level but is of growing interest to stakeholders and citizens interested in better measuring social welfare at local and regional scales. By integrating measures of built, human, social, and natural capital, GPI provides a more comprehensive assessment of social welfare than consumption-based macroeconomic indicators. GPI’s monetary basis allows these diverse metrics to be integrated, and can also facilitate intra- and inter-regional comparisons of social welfare. Ecosystem services are also increasingly recognized as important contributors to human well-being, particularly in areas where they are becoming scarce due to rapid land conversion. Despite recent advances in measuring and valuing ecosystem services, they are often not considered in decision making because of both scientific uncertainty and the difficulty in weighing these values in tradeoffs. Techniques to speed the valuation process while maintaining accuracy are thus in high demand. As public recognition of the value of ecosystem services grows, ESV can serve as the basis for a variety of policy tools, from inclusion in traditional permitting or conservation easement programs to new programs such as payments for ecosystem services. Ideally planners, citizens, and decision makers would better weigh the diverse costs and benefits of land use decisions as part of development and conservation planning. By quantifying changes in: 1) contributors to social welfare and 2) the value of ecosystem services across the urban-rural gradient, the GPI and ESV frameworks developed as part of this dissertation can thus be used to better inform local and regional policy and planning

    Scientific instruments for climate change adaptation: Estimating and optimizing the efficiency of ecosystem service provision

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    Adaptation to the consequences of climate change can depend on efficient use of ecosystem services (ES), i.e. a better use of natural services through management of the way in which they are delivered to society. While much discussion focuses on reducing consumption and increasing production of services, a lack of scientific instruments has so far prevented other mechanisms to improve ecosystem services efficiency from being addressed systematically as an adaptation strategy. This paper describes new methodologies for assessing ecosystem services and quantifying their values to humans, highlighting the role of ecosystem service flow analysis in optimizing the efficiency of ES provision

    Towards a Comprehensive Approach to Quantifying and Mapping Ecosystem Services Flows

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    25 p.Recent ecosystem services research has highlighted the importance of spatial connectivity between ecosystems and their beneficiaries. Despite this need, a systematic approach to ecosystem service flow quantification has not yet emerged. In this article, we present such an approach, which we formalize as a class of agent-based models termed “Service Path Attribution Networks†(SPANs). These models, developed as part of the Artificial Intelligence for Ecosystem Services (ARIES) project, expand on ecosystem services classification terminology introduced by other authors. Conceptual elements needed to support flow modeling include a service’s rivalness, its flow routing type (e.g., through hydrologic or transportation networks, lines of sight, or other approaches), and whether the service is supplied by an ecosystem’s provision of a beneficial flow to people or by absorption of a detrimental flow before it reaches people. We describe our implementation of the SPAN framework for five ecosystem services and discuss how to generalize the approach to additional services. SPAN model outputs include maps of ecosystem service provision, use, depletion, and flows under theoretical, possible, actual, inaccessible, and blocked conditions. We highlight how these different ecosystem service flow maps could be used to support various types of decision making for conservation and resource management planning

    From theoretical to actual ecosystem services: Mapping beneficiaries and spatial flows in ecosystem service assessments

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    Ecosystem services mapping and modeling has focused more on supply than demand, until recently. Whereas the potential provision of economic benefits from ecosystems to people is often quantified through ecological production functions, the use of and demand for ecosystem services has received less attention, as have the spatial flows of services from ecosystems to people. However, new modeling approaches that map and quantify service-specific sources (ecosystem capacity to provide a service), sinks (biophysical or anthropogenic features that deplete or alter service flows), users (user locations and level of demand), and spatial flows can provide a more complete understanding of ecosystem services. Through a case study in Puget Sound, Washington State, USA, we quantify and differentiate between the theoretical or in situ provision of services, i.e., ecosystems\u27 capacity to supply services, and their actual provision when accounting for the location of beneficiaries and the spatial connections that mediate service flows between people and ecosystems. Our analysis includes five ecosystem services: carbon sequestration and storage, riverine flood regulation, sediment regulation for reservoirs, open space proximity, and scenic viewsheds. Each ecosystem service is characterized by different beneficiary groups and means of service flow. Using the ARtificial Intelligence for Ecosystem Services (ARIES) methodology we map service supply, demand, and flow, extending on simpler approaches used by past studies to map service provision and use. With the exception of the carbon sequestration service, regions that actually provided services to people, i.e., connected to beneficiaries via flow paths, amounted to 16-66% of those theoretically capable of supplying services, i.e., all ecosystems across the landscape. These results offer a more complete understanding of the spatial dynamics of ecosystem services and their effects, and may provide a sounder basis for economic valuation and policy applications than studies that consider only theoretical service provision and/or use. Š 2014 by the author(s)

    Banking on strong rural livelihoods and the sustainable use of natural capital in post-conflict Colombia

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    In post-conflict Colombia, the government has prioritized resettlement of displaced people through development of strong rural livelihoods and the sustainable use of natural capital. In this paper, we considered government proposals for expanding payment for ecosystem services (PES) and sustainable silvopastoral systems, and private-sector investment in habitat banking. We coupled the Integrated Economic-Environmental Model (IEEM) with spatially explicit land use and land cover change and ecosystem services models to assess the potential impacts of these programs through the lens of wealth and sustainable economic development. This innovative workflow integrates dynamic endogenous feedbacks between natural capital, ecosystem services and the economic system, and can be applied to other country contexts. Results show that PES and habitat banking programs are strong investment propositions (Net Present Value of US4.4and4.4 and 4.9 billion, respectively), but only when moving beyond conventional economic analysis to include non-market ecosystem services. Where a portfolio investment approach is taken and PES is implemented with sustainable silvopastoral systems, investment returns would reach US$7.1 billion. This paper provides a detailed evaluation of the benefits of investing in rural livelihoods and enhancing Colombia’s natural capital base, with empirical evidence to inform the spatial targeting of policies to maximize economic, environmental and social outcomes. © 2023, The Author(s), under exclusive licence to Springer Nature B.V.This study was funded by the Inter-American Development Bank and the Department for Environment, Food and Rural Affairs (UK). Support for Kenneth J. Bagstad’s time was provided by the U.S. Geological Survey’s Land Change Science Program

    A methodology for adaptable and robust ecosystem services assessment

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    Ecosystem Services (ES) are an established conceptual framework for attributing value to the benefits that nature provides to humans. As the promise of robust ES-driven management is put to the test, shortcomings in our ability to accurately measure, map, and value ES have surfaced. On the research side, mainstream methods for ES assessment still fall short of addressing the complex, multi-scale biophysical and socioeconomic dynamics inherent in ES provision, flow, and use. On the practitioner side, application of methods remains onerous due to data and model parameterization requirements. Further, it is increasingly clear that the dominant one model fits all paradigm is often ill-suited to address the diversity of real-world management situations that exist across the broad spectrum of coupled human-natural systems. This article introduces an integrated ES modeling methodology, named ARIES (ARtificial Intelligence for Ecosystem Services), which aims to introduce improvements on these fronts. To improve conceptual detail and representation of ES dynamics, it adopts a uniform conceptualization of ES that gives equal emphasis to their production, flow and use by society, while keeping model complexity low enough to enable rapid and inexpensive assessment in many contexts and for multiple services. To improve fit to diverse application contexts, the methodology is assisted by model integration technologies that allow assembly of customized models from a growing model base. By using computer learning and reasoning, model structure may be specialized for each application context without requiring costly expertise. In this article we discuss the founding principles of ARIES - both its innovative aspects for ES science and as an example of a new strategy to support more accurate decision making in diverse application contexts

    The global environmental agenda urgently needs a semantic web of knowledge

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    Progress in key social-ecological challenges of the global environmental agenda (e.g., climate change, biodiversity conservation, Sustainable Development Goals) is hampered by a lack of integration and synthesis of existing scientific evidence. Facing a fast-increasing volume of data, information remains compartmentalized to pre-defined scales and fields, rarely building its way up to collective knowledge. Today's distributed corpus of human intelligence, including the scientific publication system, cannot be exploited with the efficiency needed to meet current evidence synthesis challenges; computer-based intelligence could assist this task. Artificial Intelligence (AI)-based approaches underlain by semantics and machine reasoning offer a constructive way forward, but depend on greater understanding of these technologies by the science and policy communities and coordination of their use. By labelling web-based scientific information to become readable by both humans and computers, machines can search, organize, reuse, combine and synthesize information quickly and in novel ways. Modern open science infrastructure-i.e., public data and model repositories-is a useful starting point, but without shared semantics and common standards for machine actionable data and models, our collective ability to build, grow, and share a collective knowledge base will remain limited. The application of semantic and machine reasoning technologies by a broad community of scientists and decision makers will favour open synthesis to contribute and reuse knowledge and apply it toward decision making
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