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The effects of phenomenological heating functions on the flow thermodynamics of cold T-Tauri disk winds are examined. Turbulent dissipation (mechanical) heating and a warm disk corona are invoked to heat the wind. The temperature and ionization evolution are solved for along the flow. The results allow the construction of synthetic observations; emission maps, forbidden line ratios, line fluxes and line profiles; and successfully reproduce a number of observed trends. Mechanical heating produces line ratios and fluxes that fit very well with observations. Invoking a warm disk corona successfully reproduces forbidden line profile low velocity components.  相似文献   
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Climate change related impacts, such as increased frequency and intensity of wildfires, higher temperatures, extreme changes to ecosystem processes, forest conversion and habitat degradation are threatening tribal access to valued resources. Climate change is and will affect the quantity and quality of resources tribes depend upon to perpetuate their cultures and livelihoods. Climate impacts on forests are expected to directly affect culturally important fungi, plant and animal species, in turn affecting tribal sovereignty, culture, and economy. This article examines the climate impacts on forests and the resulting effects on tribal cultures and resources. To understand potential adaptive strategies to climate change, the article also explores traditional ecological knowledge and historical tribal adaptive approaches in resource management, and contemporary examples of research and tribal practices related to forestry, invasive species, traditional use of fire and tribal-federal coordination on resource management projects. The article concludes by summarizing tribal adaptive strategies to climate change and considerations for strengthening the federal-tribal relationship to address climate change impacts to forests and tribal valued resources.  相似文献   
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Abstract— The Ordovician Lockne impact structure is located in central Sweden. The target lithology consisted of limestone and black unconsolidated shale overlaying a Precambrian crystalline basement. The Precambrian basement is uranium‐rich, and the black shale is both uranium‐ and organic‐rich. This circumstance makes Lockne a good candidate for testing the occurrence of U‐Th‐rich bitumen nodules in an impact structure setting. U‐Th‐rich bitumen nodules are formed through irradiation; hence the increase in the complexity of organic matter by a radioactive (uranium‐ and thorium‐rich) mineral phase. U‐Th‐rich bitumen nodules were detected in crystalline impact breccia and resurge deposits from the impact structure, but samples of non‐impact‐affected rocks from outside the impact structure do not contain any U‐Th‐rich bitumen nodules. This implies that in the Lockne impact structure, the nodules are associated with impact‐related processes. U‐Th‐rich bitumen nodules occur throughout the geological record and are not restricted to an impact structure setting, but our studies at Lockne show that this process of irradiation can readily occur in impact structures where fracturing of rocks and a post‐impact hydrothermal system enhances fluid circulation. The irradiation of organic matter by radioactive minerals has previously been proposed as a process for concentration of carbon on the early Earth. Impact structures are suggested as sites for prebiotic chemistry and primitive evolution, and irradiation by radioactive minerals could be an important mechanism for carbon concentration at impact sites.  相似文献   
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