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Casey D. SULLIVAN CHEN Pengju Justine Shanti ALEXANDER BAI Defeng SHI Kun 《资源与生态学报(英文版)》2018,9(5):554-565
Human-wildlife conflict (HWC) is a global conservation issue of increasing concern, and understanding the factors driving conflict is crucial for preventing or mitigating it. In many parts of China, large human populations and increasing development has led to an escalation in HWC with both carnivore and prey species. In this paper we assess herder attitudes toward blue sheep (Pseudaois nayaur, Hodgson, 1833), white lipped deer (Carvus albirostris, Przewalski, 1883), red deer (Cervus elaphus, Linnaeus, 1758), and marmot (Marmota himalayana Hodgson, 1841) through interview-based surveys conducted in 46 households across 8 villages in Qilianshan National Nature Reserve, Gansu, China. We also examine the perceived impact of three ecological-restoration policies (anti-grazing, sustainable grazing, and grass-planting policies) on livelihoods, and how this affects attitudes toward wildlife. Herders reported neutral attitudes toward wildlife species in general, but reported negative attitudes towards blue sheep. Mixed-effects modeling revealed that herder attitudes toward the target species varied significantly across villages, but other socioeconomic variables had limited explanatory power for attitudes. Furthermore, we found that while policy implementation was negatively perceived by herders, anti-grazing policy implementation and total policy implementation were positively correlated with positive attitudes toward wildlife, highlighting a potential gap between perceived threats and actual threats. Finally, we show that the leading cause of reported livestock death is preventable disease, alleviation of which may help improve attitudes toward wildlife. 相似文献
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Corwin J. Wright 《Icarus》2012,219(1):274-282
Temperature measurements from the Mars Climate Sounder on NASA’s Mars Reconnaissance Orbiter are examined for gravity wave signals using the Stockwell transform, a technique previously applied to terrestrial temperature profiles. An analysis is presented for internal-gravity waves throughout the martian atmosphere for the period July 2007–May 2009, representing a full martian year of data, divided by season. Momentum fluxes observed in the altitude range 200–20 Pa are measured as ～10?5–10?3 Pa, significantly higher than at equivalent altitudes on Earth, and are primarily peaked around the tropics. Observed orographic effects are minimal; the primary observed effects are seasonal. Waves are shown to vary significantly in wavelength with latitude, but are generally approximately zonally symmetric. Horizontal wavelengths are consistently much shorter in the northern hemisphere than the southern. 相似文献
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An Updated Review of the Middle-Late Jurassic Yanliao Biota: Chronology, Taphonomy, Paleontology and Paleoecology 总被引：1，自引：1，他引：0
The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning, northern Hebei, and southeastern Inner Mongolia. The biota lasted for about 10 million years, divided into two phases: the Bathonian-Callovian Daohugou phase (about 168-164 million years ago) and the Oxfordian Linglongta phase (164-159 million years ago). The Yanliao fossils are often taphonomically exceptional (many vertebrate skeletons, for example, are complete and accompanied by preserved integumentary features), and not only are taxonomically diverse but also include the oldest known representatives of many groups of plants, invertebrates, and vertebrates. These fossils have provided significant new information regarding the origins and early evolution of such clades as fleas, birds, and mammals, in addition to the evolution of some major biological structures such as feathers, and have demonstrated the existence of a complex terrestrial ecosystem in northeast China around the time of the Middle-Late Jurassic boundary. 相似文献
4.
MICHAEL D. CHEETHAM ANNABELLE F. KEENE RICHARD T. BUSH LEIGH A. SULLIVAN WAYNE D. ERSKINE 《Sedimentology》2008,55(6):1905-1913
Grain‐size distribution is a fundamental tool for interpreting sedimentary units within depositional systems. The techniques assessed in this study are commonly used to determine grain‐size distributions for sand‐dominated sediments. However, the degree of consistency and differences in interpretation when using a combination of grain‐size methods have not yet been assessed systematically for sand‐dominated fluvial sediments. Results obtained from laser diffraction, X‐ray attenuation and scanning electron microscopy grain‐size analysis techniques were compared with those obtained from the traditional sieve/hydrometer method. Scanning electron microscopy was shown to provide an inaccurate quantitative analysis of grain‐size distributions because of difficulties in obtaining representative samples for examination. The X‐ray attenuation method is unsuitable for sand‐dominated sediments because of its upper size range of only 300 μm. The consistently strong correlation between the laser diffraction results and the sieve/hydrometer results shows that these methods are comparable for sand‐dominated fluvial sediments. Provided that sample preparation is consistent, the latter two methods can be used together within a study of such sediments while maintaining a high degree of accuracy. These results indicate that data for sand‐dominated fluvial sediments gained from the long‐established sieve/hydrometer method can be compared with confidence to those obtained by modern studies using laser diffraction techniques. 相似文献
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R. V. Fodor Cricket Corwin Ari Roisenberg 《Contributions to Mineralogy and Petrology》1985,91(1):54-65
The Serra Geral (Paraná) continental flood basalt (SG-CFB) province in Brazil is associated with the Jurassic-Cretaceous breakup of Gondwanaland and the transition of continental to oceanic magmatism during the opening of the South Atlantic Ocean. A suite of 24 samples representative of the SG-CFB in Rio Grande do Sul, southern Brazil, shows a compositional continuum from basalt (50–53 wt% SiO2, Mg# 60-45), to basaltic andesite, to andesite, rhyodacite, and rhyolite (73 wt% SiO2). Certain compositional aspects of the mafic rocks (e.g., TiO2, K2O, CaO, Zr/Nb, Zr/Y, Ti/Zr) resemble those of basaltic dikes and flows associated with the opening of the North Atlantic Ocean.Fractionation trends are apparent in MgO variation diagrams and calculations show that basalt-basaltic andesite continuums are largely due to removal of plagioclase and clinopyroxene. These mafic rocks can be categorized as (i) having higher or lower incompatible-element contents (e.g. K2O 0.6–1.5 wt%; Rb 12–43 ppm; Ba 125–240 ppm) due to incorporation of Brazilian Archean crust or rhyolitic magma by basalt from a particular source material or to partial-melting differences of that source, and (ii) as having higher or lower TiO2, Sr, Ba, and P contents due to source heterogeneities. Crustal components are obvious in certain basaltic samples, as where K2O > 1 wt%, SiO2 > 51%, and TiO2 1%, but are insignificant in others (e.g., compositions close to those of South Atlantic basin basalts). Calculations indicate origins for intermediate and silicic rocks by removal of pl, cpx, and Ti-magnetite from basaltic andesite, but crust and magma-mixing affecting basaltic-andesite fractionates were likely also involved. Where contamination is insignificant, Zr, Nb, and Y abundances indicate T-type MORE source material like that for certain S. Atlantic Ocean basalts. Source material was essentially a 91 hybrid of N-type and P-type MORB components. N-type MORB lithosphere followed SG-CFB because decompression due to rifting crust enabled partial melting of uppermost (depleted) mantle. 相似文献
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Non dynamite seismic energy sources have shown only limited success in difficult shallow-water or marsh prospect areas, and none have applicability to both environments. Recently, a method has been devised to adapt a marine pneumatic source for operation in abrasive surroundings. A system composed of four of these modified sources together with associated emplacement and retrieval mechanisms has been developed and has proven to be a reliable and efficient seismic energy source for both shallow-water and marsh applications. 相似文献
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北美内陆西部白垩纪脊椎动物生物年代学 总被引：1，自引：1，他引：0
北美西部内陆白垩纪的脊椎动物生物年代学的研究始于19世纪90年代。前人建议的期,即陆生脊椎动物"期"或陆生哺乳动物"期"名已过十二个,但其中具有精确的定义者甚少,仅有少量的建议受到广泛认可和使用。本文定义或重新定义了10个陆生脊椎动物"期",包括了西部内陆从最老至最新的全部白垩纪—Comobluffian期(～提塘期至欧特里沃期)、Buffalogapian期(～巴列姆期至早阿普特期)、Cashenranchian期(～早阿普特期至晚阿尔布期)、Mussentuchian期(～晚阿尔布期至塞诺曼期)、Fencelakean期(土伦期至晚塞农期)、Aquilan期(～晚塞农期至早坎潘期)、Judithian期(～中坎潘期)、Kirtlandian期(～晚坎潘期)、Edmontonian期(～坎潘期末期至早马斯特里赫特期)以及Lancian期(～早马斯特里赫特期晚期)。每一个"期"的开始由一种恐龙或哺乳动物种类的首现来定义,而其结束由后续的"期"的开始来定义。这样定义的脊椎动物生物年代代表了完整的白垩纪时间表。但有些时间段(尤其是Neocomian(尼欧克姆期)的大部分以及部分"中"白垩世的一部分)缺乏足够的脊椎动物化石特征。这些白垩纪陆生脊椎动物"期"构成了一个能使北美西部内陆的脊椎动物的演化历史得以序和解释年代表。 相似文献
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H. T. Macgillivray R. J. Dodd B. V. McNally J. F. Lightfoot H. G. Corwin Jr. S. R. Heathcote 《Astrophysics and Space Science》1982,83(1-2):373-380
Geometric properties (positions, orientations and shapes) are generated in three dimensional space for galaxies in a simulated distant supercluster filament according to the galaxy orientations and filament inclinations described in Papers I (MacGillivrayet al., 1981) and II (MacGillivray and Dodd, 1982), and the distributions for projected galaxy shapes and position angles examined. The results may be used to assist the interpretation of the observed geometrical properties for galaxies in real external superclusters. 相似文献