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Diagnostic calibration and cross‐catchment transferability of a simple process‐consistent hydrologic model 
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下载免费PDF全文 The transferability of hydrologic models is of ever increasing importance for making improved hydrologic predictions and testing hypothesized hydrologic drivers. Here, we present an investigation into the variability and transferability of the recently introduced catchment connectivity model (Smith et al., 2013 ). The catchment connectivity model was developed following extensive experimental observations identifying the key drivers of streamflow in the Tenderfoot Creek Experimental Forest (Jencso et al., 2009 ; Jencso et al., 2010 ), with the goal of creating a simple model consistent with internal observations of catchment hydrologic connectivity patterns. The model was applied across seven catchments located within Tenderfoot Creek Experimental Forest to investigate spatial variability and transferability of model performance and parameterization. The results demonstrated that the model resulted in historically good fits (based on previous studies at the sites) to both the hydrograph and internal water table dynamics (corroborated with experimental observations). The impact of a priori parameter limits was also examined. It was observed that enforcing field‐based limits on model parameters resulted in slight reductions to streamflow hydrograph fits, but significant improvements to model process fidelity (as hydrologic connectivity), as well as moderate improvement in the transferability of model parameterizations from one catchment to the next. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Wolske Kimberly S. Raimi Kaitlin T. Campbell-Arvai Victoria Hart P. Sol 《Climatic change》2019,152(3-4):345-361
Climatic Change - Carbon dioxide removal (CDR) describes a suite of controversial approaches to mitigating climate change that involve removing existing carbon dioxide from the atmosphere. Through... 相似文献
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Lonny Lundsten Kyra L. Schlining Kaitlin Frasier Shannon B. Johnson Linda A. Kuhnz Julio B.J. Harvey Gillian Clague Robert C. Vrijenhoek 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(12):1573-1584
Dead whale carcasses that sink to the deep seafloor introduce a massive pulse of energy capable of hosting dynamic communities of organisms in an otherwise food-limited environment. Through long-term observations of one natural and five implanted whale carcasses in Monterey Canyon, CA, this study suggests that: (1) depth and related physical conditions play a crucial role in species composition; (2) the majority of species in these communities are background deep-sea taxa; and (3) carcass degradation occurs sub-decadally. Remotely operated vehicles (ROVs) equipped with studio quality video cameras were used to survey whales during 0.8 to seven year periods, depending on the carcass. All organisms were identified to the lowest possible taxon. Community differences among whale-falls seemed to be most strongly related to depth and water temperature. The communities changed significantly from initial establishment shortly after a carcass’ arrival at the seafloor through multiple years of steady degradation. The majority of species found at the whale-falls were background taxa commonly seen in Monterey Bay. While populations of species characterized as bone specialists, seep restricted, and of unknown habitat affinities were also observed, sometimes in great abundance, they contributed minimally to overall species richness. All whale carcasses, shallow and deep, exhibited sub-decadal degradation and a time-series of mosaic images at the deepest whale site illustrates the rapidity at which the carcasses degrade. 相似文献
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As coral reef ecosystems decline in health worldwide, reef‐associated fishes are being impacted by changes to their coral reef habitats. While previous studies have shown coral reef structure to affect the demography of reef fishes, changes in reef conditions may also impact the behavior of reef fishes as they cope with altered habitats. In this study, we examined spatial patterns of intraspecific behavioral variation in the bicolor damselfish (Stegastes partitus) across the fringing reefs of Curaçao (Caribbean Sea), and explored how this behavioral variation associated with physical and social conditions on the reef. Principal components analysis (PCA) condensed physical parameters of the reef into principal component 1 (PC1), comprising depth, coral cover (%), rugosity, and average hole size (cm2), and principal component 2 (PC2), which represented the number of holes. PC1, but not PC2, increased spatially across the reef as the habitat transitioned from coral rubble in the shallows to live coral on the reef slope. This transition in reef structure was paralleled by changes in social conditions including decreases in bicolor damselfish density in habitats with higher PC1 values. The behavior of bicolor damselfish also varied spatially with greater aggression and more frequent shelter use in habitats with lower PC1 values. Path analysis revealed robust associations between this behavioral variation and physical habitat conditions of the reef, indicating that physical – rather than social – habitat variation is the primary determinant of these spatial patterns of intraspecific behavioral variation. Taken as a whole, this coupling between physical reef structure and behavior suggests that reef fish may show altered behaviors on coral reefs degraded by anthropogenic impacts. 相似文献
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This article introduces an important, but overlooked, actor—the research associate—into methodological discussions about the production of knowledge. We use the term research associate (rather than assistant) to encompass the individuals on whom researchers rely while conducting fieldwork. We seek to avoid the unidirectional hierarchy and power dynamics between researchers and associates, which place the researcher as expert and knowledge producer while obscuring the diversity of roles conducted by field associates. Therefore, throughout this article we examine and destabilize power dynamics and hierarchies and widen the range of what is considered research assistance in the coproduction of knowledge. We also highlight the ways in which geopolitics are written into encounters with ourselves and research associates, encounters that render and reveal the complexities of vulnerability and bodily risk in fieldwork. The goals of this article are threefold: to (1) introduce the influential role of research associates during the production and dissemination of knowledge, (2) situate the work of research associates in both fieldwork and methodological literature, and (3) problematize the invisibility of research associates in academic publications and discuss possible alternatives to how authorship is credited. 相似文献
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Larry R. Nittler Rhonda M. Stroud Conel M. O'D. Alexander Kaitlin Howell 《Meteoritics & planetary science》2020,55(6):1160-1175
We report a correlated NanoSIMS‐transmission electron microscopy study of the ungrouped carbonaceous chondrite Northwest Africa (NWA) 5958. We identified 10 presolar SiC grains, 2 likely presolar graphite grains, and 20 presolar silicate and/or oxide grains in NWA 5958. We suggest a slight modification of the commonly used classification system for presolar oxides and silicates that better reflects the grains’ likely stellar origins. The matrix‐normalized presolar SiC abundance in NWA 5958 is ppm (2σ) similar to that seen in many classes of unmetamorphosed chondrites. In contrast, the matrix‐normalized abundance of presolar O‐rich phases (silicates and oxides) is ppm (2σ), much lower than seen in interplanetary dust particles and the least‐altered CR, CO, and ungrouped C chondrites, but close to that reported for CM chondrites. NanoSIMS mapping also revealed an unusual 13C‐enriched (δ13C≈100–200‰) carbonaceous rim surrounding a 1.4 μm diameter phyllosilicate grain. Transmission electron microscopy (TEM) analysis of two presolar grains with a likely origin in asymptotic giant branch stars identified one as enstatite and one as Al‐Mg spinel with minor Cr. The enstatite grain amorphized rapidly under the electron beam, suggesting partial hydration. TEM data of NWA 5958 matrix confirm that it has experienced aqueous alteration and support the suggestion of Jacquet et al. (34) that this meteorite has affinities to CM2 chondrites. 相似文献
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