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211.
Many economic processes are intertwined with landscape change. A large number of individual economic decisions shape the landscape, and in turn the changes in the landscape shape economic decisions. This article describes key research questions about the economics of landscape change and reviews the state of research knowledge. The rich and varied economic–landscape interactions are an active area of research by economists, geographers, and others. Because the interactions are numerous and complex, disentangling the causal relationships in any given landscape system is a formidable research challenge. Limited data with mismatched temporal and spatial scales present further obstacles. Nevertheless, the growing body of economic research on these topics is advancing and shares fundamental challenges, as well as data and methods, with work in other disciplines.  相似文献   
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Using data from a variety of sources, land use and vegetation in Texas were mapped with a spatial resolution of approximately 1 km. Over 600 classifications were used to characterize the land use and land cover throughout the state and field surveys were performed to assign leaf biomass densities, by species, to the land cover classifications. The total leaf biomass densities associated with these land use classifications ranged from 0 to 556 g/m2, with the highest assigned total and oak leaf biomass densities located in central and eastern Texas. The land cover data were used as input to a biogenic emissions model, GLOBEIS2. Estimates of biogenic emissions of isoprene based on GLOBEIS2 and the new land cover data showed significant differences when compared to biogenic isoprene emissions estimated using previous land cover data and emission estimation procedures. For example, for one typical domain in eastern Texas, total daily isoprene emissions increased by 38% with the new modeling tools. These results may ultimately affect the way in which ozone and other photochemical pollutants are modeled and evaluated in the state of Texas.  相似文献   
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Despite a common understanding of the harmful impacts of Western conservation models that separate people from nature, widespread progress toward incorporating socioeconomic, political, cultural, and spiritual considerations in conservation practice is lacking. For some, the concept of nature-based solutions (NbS) is seen as an interdisciplinary and holistic pathway to better integrate human well-being in conservation. We examined how conservation practitioners in the United States view NbS and how social considerations are or are not incorporated in conservation adaptation projects. We interviewed 28 individuals working on 15 different such projects associated with the Wildlife Conservation Society's Climate Adaptation Fund. We completed 2 rounds of iterative coding in NVivo 12.6.1 to identify in the full text of all interview responses an a priori set of themes related to our research questions and emergent themes. Many respondents saw this moment as a tipping point for the field (one in which the perceived values of social considerations are increasing in conservation practice) (76%) and that social justice concerns and the need to overcome racist and colonial roots of Western conservation have risen to the forefront. Respondents also tentatively agreed that NbS in conservation could support social and ecological outcomes for conservation, but that it was far from guaranteed. Despite individual intention and awareness among practitioners to incorporate social considerations in conservation practice, structural barriers, including limited funding and inflexible grant structures, continue to constrain systemic change. Ultimately, systemic changes that address power and justice in policy and practice are required to leverage this moment to more fully address social considerations in conservation.  相似文献   
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Although lava-rock-based biofilters have demonstrated their efficiencies for hydrogen sulfide (H2S) removal found in odorous air emissions, the biogeochemical basis for this removal is unclear. In this study, samples of lava rock and rinse water from biofilters at Cedar Rapids Water Pollution Control Facilities (Iowa) were used to study the structure and chemical composition of lava rock and to identify the predominant microorganism(s) present in lava-rock-based biofilters. It was found that iron, in the form of Fe2+ and Fe3+, was present in lava rock. Although literature suggests that Acidithiobacillus thiooxidans are primarily responsible for gaseous H2S removal in biofilters, our study showed that Acidithiobacillus ferrooxidans was the dominant microorganism in the lava-rock-based biofilters. A novel mechanism for H2S removal in a lava-rock-based biofilter is proposed based on the biogeochemical analysis of lava rock.  相似文献   
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This paper briefly outlines the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and what is meant by GHS implementation in terms of policy-related information for decision-makers plus a framework of actions to enable such policies to be effectively undertaken. The paper discusses the need for simple indicators to measure progress with GHS implementation. Two groups of indicators have been described that comprehensively reflect basic components of GHS implementation. The first group was presented as aggregated indicators or indices, for national capability evaluation. Indicators to evaluate management performance linked to stated objectives were presented as the second group. Information from an Organisation for Economic Co-operation and Development (OECD) published questionnaire on GHS implementation and a questionnaire by the Intergovernmental Forum on Chemical Safety (IFCS) on chemical safety that included GHS have provided the basic information for applying the management capability indicators approach. Through the use of information in these two questionnaires, country-relevant and regional progress with GHS implementation was illustrated. Despite the GHS implementation target of 2008 set by the Johannesburg Plan of Implementation, very few countries have reported they have achieved this target. The simple management indicators proposed in this paper are based on adoption of a questionnaire and a numerical scoring system that could be used to chart progress towards GHS implementation. It was concluded, therefore, that the use of indicators as described in this paper does provide a quick survey of the overall situation in a country and facilitates comparison between countries across regions in terms of GHS implementation. Furthermore such results may indicate which countries require additional assistance with GHS implementation thus strengthening policies and actions across all sectors and involving governments, business, trade, and civil society.  相似文献   
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