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Public sector decisions concerning land use can benefit from a consistent accounting of economic values represented in alternative uses. While conventional economic valuation may not represent all interests bearing on optimal land use, ignorance or misuse of economic principles in the decision process may lead to socially undesirable outcomes. We make use of an impact assessment technique based on the U.S. Forest Service Micro IMPLAN model to compile and measure the economic consequences of alternative agricultural land use. This approach provides consistent measurement of economic impacts based on quantified linkages among the different sectors represented in Hood River County, Oregon. An orchard and a golf course are compared in terms of the magnitude and distribution of direct, indirect, and induced economic impacts arising from alternative uses of a designated land parcel. While the results are not generalizable to specific applications, the approach highlights the key economic variables that generate economic benefits in alternative uses. 相似文献
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Amazonian indigenous populations are approaching a critical stage in their history in which increasing education and market integration, rapid population growth and degradation of natural resources threaten the survival of their traditions and livelihoods. A topic that has hardly been touched upon in this context is migration and population mobility. We address this by analysing a unique longitudinal dataset from the Ecuadorian Amazon on the spatial mobility of five indigenous groups and mestizo co-residents. Analyses reveal traditional and new forms of population mobility and migrant selectivity, including gendered forms of marriage migration and rural-urban moves driven by education. These results illustrate a dynamic present and an uncertain future for indigenous populations in which rural, natural-resource-based lifeways may well be sustained but with increasing links to urban areas. 相似文献
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Alla Ostrinskaya M.S. Roderick R. Kunz Ph.D. Michelle Clark Ph.D. Richard P. Kingsborough Ph.D. Ta‐Hsuan Ong Ph.D. Sandra Deneault 《Journal of forensic sciences》2019,64(1):223-230
A flow‐injection analysis tandem mass spectrometry (FIA MSMS) method was developed for rapid quantitative analysis of 10 different inorganic and organic explosives. Performance is optimized by tailoring the ionization method (APCI/ESI), de‐clustering potentials, and collision energies for each specific analyte. In doing so, a single instrument can be used to detect urea nitrate, potassium chlorate, 2,4,6‐trinitrotoluene, 2,4,6‐trinitrophenylmethylnitramine, triacetone triperoxide, hexamethylene triperoxide diamine, pentaerythritol tetranitrate, 1,3,5‐trinitroperhydro‐1,3,5‐triazine, nitroglycerin, and octohy‐dro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine with sensitivities all in the picogram per milliliter range. In conclusion, FIA APCI/ESI MSMS is a fast (<1 min/sample), sensitive (~pg/mL LOQ), and precise (intraday RSD < 10%) method for trace explosive detection that can play an important role in criminal and attributional forensics, counterterrorism, and environmental protection areas, and has the potential to augment or replace several of the existing explosive detection methods. 相似文献
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