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您的检索式：作者名="David Durrheim"
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| 1 | Diversity and production in an Afromontane Forest显示文摘Background:This contribution evaluates the effect of forest structure and tree species diversity on plot productivity and individual tree growth in the unique Knysna forests in Southern Africa using mapped tree data from an observational study that has been re-measured over a period of 40 years.Methods:The effects of tree species diversity and forest structure on tree growth and forest production are evaluated on three levels of resolution:a) the forest community(canopy,sub-canopy species),b) the subplots(number of trees per ha,skewness of the diameter distribution,diameter coefficient of variation) and c) the immediate neighborhood of selected reference trees('Mingling','Dominance',Aggregation' and 'Size Variation').Results:An analysis of the community level identified two distinct clusters,one including dominant/canopy species with the highest growth rates and a greater variation of growth,and another cluster which includes the remaining subcanopy species which have a smaller maximum size and lower rates of growth.The area-based structure variables on plot level have a highly significant effect on total basal area growth.However,the effects of forest density and species richness on productivity were not straight forward.Maximum basal area production of about 0.75 m^2/ha/year is achieved at medium levels of richness(around 20 species per ha) and medium levels of density(around 30 m^2/ha basal area) using percentile regression estimates.The relative 'Dominance' of a selected reference tree had a highly significant effect on individual tree growth on all investigated species.Other neighbourhood structure variables were only occasionally significant or not significant at all.Conclusion:This contribution presents a new theoretical framework for analysing natural forests that includes community,plot and neighborhood variables of forest structure and diversity,and a first specific analysis of the structure and dynamics of the Knysna Afromontane Forest,based on a unique set of longterm observations.The species-area(SAR) model developed in this study,represents a new general approach that can be used to derive a common standard of tree species diversity for different plot sizes,the species richness per hectare. | Klaus v.Gadow GongQiao Zhang Graham Durrheim David Drew Armin Seydack | 2016 | Forest Ecosystems2016，3，4： | 5 |
| 2 | 狂犬病暴露前免疫:一项系统综述显示文摘为了综述狂犬病暴露前免疫的安全性和免疫原性(包括加速程序、与其他疫苗和增强剂的联合应用)、其成本效益和使用建议。在PubMed、Centre for Agriculture and Biosciences International、Cochrane Library、Web of Science databases检索2007年至2016年1月29日期间发表的关于狂犬病暴露前免疫的论文,回顾在秘鲁和菲律宾开展的暴露前免疫运动的现场数据。 | Jocelyn A Kessels Sergio Recuenco Ana Maria Navarro-Vela Raffy Deray Marco Vigilato Hildegund E rtl David Durrheim Helen Rees Louis H Nel Bernadette Abela-Ridder Deborah Briggsk 吕新军(编译) | 2019 | 中华实验和临床病毒学杂志2019，33，5： | 0 |
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