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国土与自然资源研究 1992年第S1期 3-5,33页

作者： Shugart H.H 周德本黑龙江省科学院自然资源研究所

在长期定位研究中生态模型的一个更有价值的应用是解释结果时提供一个理论上的来龙去脉。JABONA模型(Botkin etal,1972)一个长期森林发展和演替的模拟模型,其最初发展是模拟位子 New hampshire的 hubbard vnook实验林的林木生长 (Likens... 详细信息

在长期定位研究中生态模型的一个更有价值的应用是解释结果时提供一个理论上的来龙去脉。JABONA模型(Botkin etal,1972)一个长期森林发展和演替的模拟模型,其最初发展是模拟位子 New hampshire的 hubbard vnook实验林的林木生长 (Likens etal,1977)。模型的应用表明期望的集水区植物长期生物量和营养动态是一本书(Bormon。and Likens,1979).的中心论点之一,这本书总结了这一研究的一些主要发现。

关键词：长期生态研究理论模型生物量 hubbard 中心论点生态模型模拟模型一本锯齿状总初级生产量

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Gap models across micro-to mega-scales of time and space:examples of Tansley’s ecosystem concept

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Forest Ecosystems 2020年第2期7卷 172-189页

作者： h.h.shugart Adrianna Foster Bin Wang Dan Druckenbrod Jianyong Ma Manuel Lerdau Sassan Saatchi Xi Yang Xiaodong Yan University of Virginia 291 McCormick RdCharlottesvilleVA 22904USA NASA Goddard Space Flight Center 8800 Greenbelt RdGreenbeltMD 20771USA Department of Ecology and Evolutionary Biology University of CaliforniaIrvineCAUSA Department of Geological Environmentaland Marine SciencesRider University2083 Lawrenceville RdLawrencevilleNJ 08648USA College of Plant Science and Technology Huazhong Agriculture UniversityWuhanHubeiChina Jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Beijing Normal University Jingshi Keji Building B-811NO.12 Xueyuan South RoadHaidian DistrictBeijing 100875China.

Background:Gap models are individual-based models for forests.They simulate dynamic multispecies assemblages over multiple tree-generations and predict forest responses to altered environmental conditions.Their development emphases designation of the significant biological and ecological processes at appropriate time/space scales.Conceptually,they are with consistent with A.G.Tansley’s original definition of"the ecosystem".Results:An example microscale application inspects feedbacks among terrestrial vegetation change,air-quality changes from the vegetation’s release of volatile organic compounds(VOC),and climate change effects on ecosystem production of VOC’s.Gap models can allocate canopy photosynthate to the individual trees whose leaves form the vertical leaf-area profiles.VOC release depends strongly on leaf physiology by species of these trees.Leaf-level VOC emissions increase with climate-warming.Species composition change lowers the abundance of VOC-emitting taxa.In interactions among ecosystem functions and biosphere/atmosphere exchanges,community composition responses can outweigh physiological responses.This contradicts previous studies that emphasize the warming-induced impacts on leaf function.As a mesoscale example,the changes in climate(warming)on forests including pest-insect dynamics demonstrates changes on the both the tree and the insect populations.This is but one of many cases that involve using a gap model to simulate changes in spatial units typical of sampling plots and scaling these to landscape and regional levels.As this is the typical application scale for gap models,other examples are identified.The insect/climatechange can be scaled to regional consequences by simulating survey plots across a continental or subcontinental zone.Forest inventories at these scales are often conducted using independent survey plots distributed across a region.Model construction that mimics this sample design avoids the difficulties in modelling spatial interactions,but we also discuss simulation at these

关键词： Pollution Climate change Global forest productivity Individual-based models Ecological scale Forest dynamics

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Postpartum meloxicam administration alters plasma haptoglobin, polyunsaturated fatty acid, and oxylipid concentrations in postpartum ewes

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Journal of Animal Science and Biotechnology 2020年第4期11卷 1047-1060页

作者： Katie EOlagaray Barry J.Bradford Lorraine M.Sordillo Jeffery C.Gandy Laman K.Mamedova Turner h.Swartz Trey D.Jackson Emma K.Persoon Caitlin S.shugart Curtis R.Youngs Department of Animal Sciences and Industry Kansas State UniversityManhattan 66506USA College of Veterinary Medicine Michigan State University2265K Anthony HallEast LansingMI 48824-1225USA Department of Animal Science Iowa State UniversityAmesIAUSA.

Background: Postpartum inflammation is a natural and necessary response;however, a dysfunctional inflammatory response can be detrimental to animal productivity. The objective of this study was to determine the effects of a non-steroidal anti-inflammatory drug(meloxicam) on ewe postpartum inflammatory response, ewe plasma polyunsaturated fatty acid and oxylipid concentrations, and lamb growth.Results: After lambing, 36 hampshire and hampshire × Suffolk ewes were sequentially assigned within type of birth to control(n = 17) or meloxicam orally administered on d 1 and 4 of lactation(MEL;90 mg, n = 19). Milk and blood samples were collected on d 1(prior to treatment) and d 4. Milk glucose-6-phosphate was not affected by MEL. Plasma haptoglobin(hp) concentrations were less for MEL ewes;control ewes with greater d 1 hp concentrations had elevated hp on d 4, but this was not the case for MEL-treated ewes. Treatment with MEL increased plasma arachidonic acid concentration by more than 4-fold in ewes rearing singles but decreased concentrations of 9,10-dihydroxyoctadecenoic acid, prostaglandin F2α, 8-iso-prostaglandin E2, and 8,9-dihydroxyeicosatetraenoic acid. Nine oxylipids in plasma had interactions of treatment with d 1 hp concentration,all of which revealed positive associations between d 1 hp and d 4 oxylipid concentrations for CON, but neutral or negative relationships for MEL. MEL decreased 13-hydroxyoctadecadienoic acid:13-oxooctadecadienoic acid ratio and tended to increase 9-hydroxyoctadecadienoic acid:9-oxooctadecadienoic acid ratio(both dependent on d 1 values), indicating progressive metabolism of linoleic acid-derived oxylipids occurred by enzymatic oxidation after MEL treatment. Meloxicam reduced oxylipids generated across oxygenation pathways, potentially due to an improved redox state.Conclusions: Postpartum MEL treatment of ewes decreased plasma concentrations of hp and several oxylipids,with the greatest impact in ewes with biomarkers reflecting a greater inflammatory state before treatment. Antiinfla

关键词： Eicosanoid Inflammation Lactation Nonsteroidal anti-inflammatory drug Sheep

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