Weather or weathering?Growth of Nothofagus dombeyi on volcanic soils differing in nitrogen and phosphorus concentrations  

作　　者：Christoph Walter Cecilia A.Pérez Frank M.Thomas 

机构地区：[1]Faculty of Regional and Environmental Sciences,Geobotany,University of Trier,Behringstraße 21,54296 Trier,Germany [2]Departamento de Ecología de Ecosistemas,Instituto de Ecología y Biodiversidad(IEB),Alameda 340,Santiago,Chile

出　　处：《Journal of Plant Ecology》2016年第5期596-607,共12页植物生态学报（英文版）

基　　金：Fondo Nacional de Desarrollo Científico y Tecnológico(Fondecyt),Chile(Fondecyt Regular 1090135).

摘　　要：Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem increment of Nothofagus dombeyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central Chile.Methods We took soil samples and tree increment cores from five proximate sites(1000-1300 m a.s.l.)that are located in the volcanic region of the Conguillío National Park and differ in the age of the substrate(Miocene—3500 years B.P.)and in its concentrations of nitrogen(N)and phosphorus(P).The soil samples were also analysed on their concentrations of other plant mineral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem basal area increment(BAI)were related to climate parameters.In selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determined and related to growth and climate parameters.Important FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but mineral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate age.The BAI was largest on the soil with the highest concentration of plant-available P.In contrast to BAI,tree-ring chronologies did not differ among the study sites.However,tree-ring chronologies and BAI exhibited significantly positive correlations with summer precipitation,and negative correlations,with summer(December)temperature.A negative correlation was found betweenδ^(13)C and precipitation anomalies in the growing season(November-March).We interpret the negative correlations between growth and temperature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an impairment of net carbon assimilation by anomalously warm weather conditions during the growing season.We conclude that the growth of N.dombeyi is mainly affected by high temperature and low precipitation in spring and summer irrespective

关 键 词：ANDISOL annual ring DENDROECOLOGY temperate broadleaf forest weather anomalies 

分 类 号：R73[医药卫生—肿瘤]