Brandisia is a shrubby genus of about eight species distributed basically in East Asian evergreen broadleaved forests(EBLFs),with distribution centers in the karst regions of Yunnan,Guizhou,and Guangxi in southwestern...Brandisia is a shrubby genus of about eight species distributed basically in East Asian evergreen broadleaved forests(EBLFs),with distribution centers in the karst regions of Yunnan,Guizhou,and Guangxi in southwestern China.Based on the hemiparasitic and more or less liana habits of this genus,we hypothesized that its evolution and distribution were shaped by the development of EBLFs there.To test our hypothesis,the most comprehensive phylogenies of Brandisia hitherto were constructed based on plastome and nuclear loci(nrDNA,PHYA and PHYB);then divergence time and ancestral areas were inferred using the combined nuclear loci dataset.Phylogenetic analyses reconfirmed that Brandisia is a member of Orobanchaceae,with unstable placements caused by nuclear-plastid incongruences.Within Brandisia,three major clades were well supported,corresponding to the three subgenera based on morphology.Brandisia was inferred to have originated in the early Oligocene(32.69 Mya)in the Eastern Himalayas-SW China,followed by diversification in the early Miocene(19.45 Mya)in karst EBLFs.The differentiation dates of Brandisia were consistent with the origin of keystone species of EBLFs in this region(e.g.,Fagaceae,Lauraceae,Theaceae,and Magnoliaceae)and the colonization of other characteristic groups(e.g.,Gesneriaceae and Mahonia).These findings indicate that the distribution and evolution of Brandisia were facilitated by the rise of the karst EBLFs in East Asia.In addition,the woody and parasitic habits,and pollination characteristics of Brandisia may also be the important factors affecting its speciation and dispersal.展开更多
The distribution,quantification and fluxes of Pb were examined in an evergreen broadleaved forest in western Greece for three hydrological years.More specifically,concentrations and annual fluxes of Pb were determined...The distribution,quantification and fluxes of Pb were examined in an evergreen broadleaved forest in western Greece for three hydrological years.More specifically,concentrations and annual fluxes of Pb were determined in bulk and throughfall deposition as well as litterfall.The Pb concentrations were also measured in forest floor and mineral soil up to 80 cm and the isotopic ratios of 206Pb/207Pb were determined in soil layers and the parent rock material.High variability in the fluxes of the metal among the three hydrological years were found,evidence of the variability of Pb deposition in time.Litterfall fractions with a large surface area,like holm oak flowers,had high Pb concentrations.Applying a steady state model and considering the Pb amounts in throughfall and litterfall as inputs on the forest floor,the mean residence time of Pb in the forest floor was 94 years with a coefficient of variation equal to 41%.More observations are needed to lower the variability of the mean residence time.The isotopic ratio in the rock material was defined as the lithogenic ratio.The statistical tests showed that the petrol derived Pb migrated to the depth of 20 cm and its percentages in the soil pedon was in the range of 62%in the L horizon to 11%in the 10–20cm layer.In higher depths(>40 cm)preindustrial anthropogenic Pb affected the isotopic ratio.As the forest under consideration is remote from industrial activities,the results can serve as a baseline for future studies on Pb distribution and quantification.展开更多
The subtropical evergreen broadleaved forests(EBLFs),ranging in occurrence from c.23°N to 39°N and 97°E to 141°E,are amongst the most characteristic biomes in East Asia and are common in South Chin...The subtropical evergreen broadleaved forests(EBLFs),ranging in occurrence from c.23°N to 39°N and 97°E to 141°E,are amongst the most characteristic biomes in East Asia and are common in South China.They contribute fundamentally to both the biodiversity function and ecosystem services of the East Asiatic floristic kingdom.The East Asian subtropical EBLFs are considered as unique zonal vegetation that might have developed in concert with the Asian monsoons,particularly展开更多
The plant communities and their microclimates were surveyed and observed,and the soil fertilities were determined in six plots of evergreen broadleaved forests of different sizes and similar slope aspects on Jinyun Mo...The plant communities and their microclimates were surveyed and observed,and the soil fertilities were determined in six plots of evergreen broadleaved forests of different sizes and similar slope aspects on Jinyun Mountains of Chongqing in China from April to October,2003.The relationships of biotic and abiotic factors were analyzed using the Simpson,Shannon-Wiener,and Hill diversity indices,and stepwise multilinear regression analyses techniques.The results showed that compared with continuous evergreen broadleaved forests,five fragmentations had a lower species diversity index,and different life forms showed differences in diversity index.With the decrease in patch areas,the daily differences in air temperature(ΔTa),ground surface temperature(ΔTs),daily differences in relative humidity(ΔRH),maximum wind velocity(Vmax),differences in photosynthetic available radiation(ΔPAR)(at noon)of both edges and interiors,all tended to increase.Maximum wind velocity(Vmax)and photo effective radiation in forest edges were higher than those in interior forest,which presented a stronger temperature-gained edge effect.In all the fragmentations of evergreen broadleaved forests,the depth of the edge effect was the nearest from interior forest in the biggest patch(about 15 meters away from interior forest),while the depth of the edge effect was the farthest from interior forest in the smallest patch(about 25 meters away from interior forest).With regard to the water conservation function,soil water content improved along with increasing species diversity.Some of the nutritional function substances of soil increased with increasing species diversity.The elements of microclimate,such as Ta,ΔTa,ΔTs,ΔRH,Vmax,and PAR,changed along with the extent of fragmented forest.展开更多
Estimating stand transpiration of natural forests using traditional methods through up-scaling of sap fl ux density from sample trees based on stand sapwood area only is diffi cult because of the complexity of species...Estimating stand transpiration of natural forests using traditional methods through up-scaling of sap fl ux density from sample trees based on stand sapwood area only is diffi cult because of the complexity of species,ages,and hierarchical structure of natural forests.To improve stand transpiration estimation,we developed an up-scaling method by considering the tree dominance eff ect based on the assumption that individual tree transpiration is aff ected by crown dominance and species,in addition to factors previously considered such as meteorological conditions,sapwood area,and soil moisture.In this study,the meteorological factors,soil moisture,and sap fl ux density of 15 sample trees of diff erent species and dominance in a natural evergreen and deciduous broadleaved mixed forest were simultaneously monitored from March 2012 to February 2014 in the Karst mountain region in southwestern China.After establishing a single tree transpiration model which considers the eff ects of dominance and species,an up-scaling method was explored to estimate stand transpiration.The results show that the transpiration intensity increased exponentially with increasing tree dominance.The contribution to annual stand transpiration from a few dominant trees(5.4%of trees, 28.2% of basal area) was up to 65.0%. The correspondingcontribution was 16.2% from sub-dominant trees(7.6% of trees, 16.2% of basal area) and 22.8% from middleandlower-layer trees (87.0% of trees, 55.6% of basal area).The variation of individual tree transpiration was mainly(97.9%) explained by tree dominance, but very weakly bytree species. The estimated annual stand transpiration was300.2 mm when using the newly developed method whichconsiders tree dominance, 52.5 mm (14.9%) lower than theestimation (352.7 mm) of traditional method which considersonly the sapwood area eff ect, and 8.5 mm (2.7%) lowerthan the estimation (308.6 mm) which considers the eff ectsof both species composition and sapwood area. The maintree characteristics aff ecting stand transpiration are tree size(sapwood area) and dominance. Consideration of tree dominancewill signifi cantly improve stand transpiration estimationand provide a more solid basis for guiding integratedforest-water management at stand scale.展开更多
It is well--known that broadlcaved/Korean pine forests distribute in the areanear the broad seas in the cast Asia.TheStudy history or the forests is coincided withthat of its exploitation and destroying.
Background:Carbon(C),nitrogen(N),and phosphorus(P)stoichiometry is a key indicator of nutrient utilization in plants,and C/N/P ratios are related to the life histories and adaptation strategies of tree species.However...Background:Carbon(C),nitrogen(N),and phosphorus(P)stoichiometry is a key indicator of nutrient utilization in plants,and C/N/P ratios are related to the life histories and adaptation strategies of tree species.However,no consensus has been reached on how leaf stoichiometric characteristics are affected by forest type and stand ages.The relationships between leaf stoichiometry and geographical,meteorological,and soil factors also remain poorly understood.Methods:Leaf and soil were sampled from forest stands of different age groups(young,middle-aged,near-mature,and mature)in two forest types(Chinese fir(Cunninghamia lanceolata)forests and evergreen broadleaved forests).The relationships between leaf C,N,and P stoichiometric parameters and geographical,meteorological,and soil factors were analysed by using redundancy analysis(RDA)and stepwise linear regression analysis.Results:Leaf C concentrations peaked in the near-mature stands with increasing age irrespective of forest type.Leaf N and P concentrations fluctuated with a rising trend in Chinese fir forests,while decreased first and increased later from young to mature phases in natural evergreen broadleaved forests.Chinese fir forests were primarily limited by N and P,while natural evergreen broadleaved forests were more susceptible to P limitation.Leaf C,N,and P stoichiometric characteristics in Chinese fir forests were mainly affected by the soil total P concentration(SP),longitude(LNG),growing season precipitation(GSP)and mean temperature in July(JUT).The leaf C concentration was mainly affected by GSP and JUT;leaf N and P concentrations were both positively correlated with LNG;and leaf P was positively correlated with SP.In evergreen broadleaved forests,however,leaf stoichiometric parameters displayed significant correlations with latitude(LAT)and mean annual precipitation(MAP).Conclusions:Leaf stoichiometry differed among forest stands of different age groups and forest types.Leaf C,N,and P stoichiometry was primarily explained by the combinations of SP,LNG,GSP and JUT in Chinese fir forests.LAT and MAP were the main controlling factors affecting the variations in the leaf C,N,and P status in natural evergreen broadleaved forests,which supports the temperature-plant physiological hypothesis.These findings improve the understanding of the distribution patterns and driving mechanisms of leaf stoichiometry linked with stand age and forest type.展开更多
Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variabl...Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variables as predictors.Methods:The data were obtained from 44 permanent plots used to monitor stand growth under forest management in the study area.Results:The generalized Bertalanffy-Richards model performed better than the other generalized models in predicting the total height of the species under study.For the genera Pinus and Quercus,the models were successfully calibrated by measuring the height of a subsample of three randomly selected trees close to the mean d,whereas for species of the genera Cupressus,Arbutus and Alnus,three trees were also selected,but they are specifically the maximum,minimum and mean d trees.Conclusions:The presented equations represent a new tool for the evaluation and management of natural forest in the region.展开更多
The biomass and productivity of Schima superba-Castanopsis carlesii forests in Tiantong,Zhejiang Province,were determined using overlapping quadrants and stem analyses.The total community biomass was(225.3±30.1) ...The biomass and productivity of Schima superba-Castanopsis carlesii forests in Tiantong,Zhejiang Province,were determined using overlapping quadrants and stem analyses.The total community biomass was(225.3±30.1) t hm-2,of which the aboveground parts accounted for 72.0% and the underground parts accounted for 28.0%.About 87.2% of biomass existed in the tree layer.The resprouting biomass was small,of which over 95.0% occurred in the shrub layer.The productivity of the aboveground parts of the community was(386.8±98.9) g m-2a-1,in which more than 96.0% was present at the tree level.The trunk's contribution to productivity was the greatest,while that of leaves was the smallest.In China,the community biomass of subtropical evergreen broadleaved forests differs significantly with the age of the forest.The community biomass of the 52-year-old S.superba-C.carlesii forests in this study was lower than the average biomass of subtropical evergreen broadleaved forests in China,and was lower than the biomass of other subtropical evergreen broadleaved forests elsewhere in the world.Moreover,its productivity was lower than the model estimate,indicating that without disturbance,this community has great developmental potential in terms of community biomass and productivity.展开更多
基金funded by the Key Projects of the Joint Fund of the National Natural Science Foundation of China(U1802232)the national youth talent support program+2 种基金CAS"Light of West China"ProgramYunnan youth talent support program(YNWR-QNBJ-2018-183 to Y.N.)Vietnam Academy of Science and Technology(UQDTCB.06/22-23)。
文摘Brandisia is a shrubby genus of about eight species distributed basically in East Asian evergreen broadleaved forests(EBLFs),with distribution centers in the karst regions of Yunnan,Guizhou,and Guangxi in southwestern China.Based on the hemiparasitic and more or less liana habits of this genus,we hypothesized that its evolution and distribution were shaped by the development of EBLFs there.To test our hypothesis,the most comprehensive phylogenies of Brandisia hitherto were constructed based on plastome and nuclear loci(nrDNA,PHYA and PHYB);then divergence time and ancestral areas were inferred using the combined nuclear loci dataset.Phylogenetic analyses reconfirmed that Brandisia is a member of Orobanchaceae,with unstable placements caused by nuclear-plastid incongruences.Within Brandisia,three major clades were well supported,corresponding to the three subgenera based on morphology.Brandisia was inferred to have originated in the early Oligocene(32.69 Mya)in the Eastern Himalayas-SW China,followed by diversification in the early Miocene(19.45 Mya)in karst EBLFs.The differentiation dates of Brandisia were consistent with the origin of keystone species of EBLFs in this region(e.g.,Fagaceae,Lauraceae,Theaceae,and Magnoliaceae)and the colonization of other characteristic groups(e.g.,Gesneriaceae and Mahonia).These findings indicate that the distribution and evolution of Brandisia were facilitated by the rise of the karst EBLFs in East Asia.In addition,the woody and parasitic habits,and pollination characteristics of Brandisia may also be the important factors affecting its speciation and dispersal.
文摘The distribution,quantification and fluxes of Pb were examined in an evergreen broadleaved forest in western Greece for three hydrological years.More specifically,concentrations and annual fluxes of Pb were determined in bulk and throughfall deposition as well as litterfall.The Pb concentrations were also measured in forest floor and mineral soil up to 80 cm and the isotopic ratios of 206Pb/207Pb were determined in soil layers and the parent rock material.High variability in the fluxes of the metal among the three hydrological years were found,evidence of the variability of Pb deposition in time.Litterfall fractions with a large surface area,like holm oak flowers,had high Pb concentrations.Applying a steady state model and considering the Pb amounts in throughfall and litterfall as inputs on the forest floor,the mean residence time of Pb in the forest floor was 94 years with a coefficient of variation equal to 41%.More observations are needed to lower the variability of the mean residence time.The isotopic ratio in the rock material was defined as the lithogenic ratio.The statistical tests showed that the petrol derived Pb migrated to the depth of 20 cm and its percentages in the soil pedon was in the range of 62%in the L horizon to 11%in the 10–20cm layer.In higher depths(>40 cm)preindustrial anthropogenic Pb affected the isotopic ratio.As the forest under consideration is remote from industrial activities,the results can serve as a baseline for future studies on Pb distribution and quantification.
基金funded by the National Key Basic Research Program of Chinathe Strategic Priority Research Program of the Chinese Academy of Sciences+2 种基金the National Natural Science Foundation of Chinathe Applied Fundamental Research Foundation of Yunnan Provincethe China Postdoctoral Science Foundation
文摘The subtropical evergreen broadleaved forests(EBLFs),ranging in occurrence from c.23°N to 39°N and 97°E to 141°E,are amongst the most characteristic biomes in East Asia and are common in South China.They contribute fundamentally to both the biodiversity function and ecosystem services of the East Asiatic floristic kingdom.The East Asian subtropical EBLFs are considered as unique zonal vegetation that might have developed in concert with the Asian monsoons,particularly
基金This study was supported by the National Natural Science Foundation of China(Grant No.30370279).
文摘The plant communities and their microclimates were surveyed and observed,and the soil fertilities were determined in six plots of evergreen broadleaved forests of different sizes and similar slope aspects on Jinyun Mountains of Chongqing in China from April to October,2003.The relationships of biotic and abiotic factors were analyzed using the Simpson,Shannon-Wiener,and Hill diversity indices,and stepwise multilinear regression analyses techniques.The results showed that compared with continuous evergreen broadleaved forests,five fragmentations had a lower species diversity index,and different life forms showed differences in diversity index.With the decrease in patch areas,the daily differences in air temperature(ΔTa),ground surface temperature(ΔTs),daily differences in relative humidity(ΔRH),maximum wind velocity(Vmax),differences in photosynthetic available radiation(ΔPAR)(at noon)of both edges and interiors,all tended to increase.Maximum wind velocity(Vmax)and photo effective radiation in forest edges were higher than those in interior forest,which presented a stronger temperature-gained edge effect.In all the fragmentations of evergreen broadleaved forests,the depth of the edge effect was the nearest from interior forest in the biggest patch(about 15 meters away from interior forest),while the depth of the edge effect was the farthest from interior forest in the smallest patch(about 25 meters away from interior forest).With regard to the water conservation function,soil water content improved along with increasing species diversity.Some of the nutritional function substances of soil increased with increasing species diversity.The elements of microclimate,such as Ta,ΔTa,ΔTs,ΔRH,Vmax,and PAR,changed along with the extent of fragmented forest.
文摘Estimating stand transpiration of natural forests using traditional methods through up-scaling of sap fl ux density from sample trees based on stand sapwood area only is diffi cult because of the complexity of species,ages,and hierarchical structure of natural forests.To improve stand transpiration estimation,we developed an up-scaling method by considering the tree dominance eff ect based on the assumption that individual tree transpiration is aff ected by crown dominance and species,in addition to factors previously considered such as meteorological conditions,sapwood area,and soil moisture.In this study,the meteorological factors,soil moisture,and sap fl ux density of 15 sample trees of diff erent species and dominance in a natural evergreen and deciduous broadleaved mixed forest were simultaneously monitored from March 2012 to February 2014 in the Karst mountain region in southwestern China.After establishing a single tree transpiration model which considers the eff ects of dominance and species,an up-scaling method was explored to estimate stand transpiration.The results show that the transpiration intensity increased exponentially with increasing tree dominance.The contribution to annual stand transpiration from a few dominant trees(5.4%of trees, 28.2% of basal area) was up to 65.0%. The correspondingcontribution was 16.2% from sub-dominant trees(7.6% of trees, 16.2% of basal area) and 22.8% from middleandlower-layer trees (87.0% of trees, 55.6% of basal area).The variation of individual tree transpiration was mainly(97.9%) explained by tree dominance, but very weakly bytree species. The estimated annual stand transpiration was300.2 mm when using the newly developed method whichconsiders tree dominance, 52.5 mm (14.9%) lower than theestimation (352.7 mm) of traditional method which considersonly the sapwood area eff ect, and 8.5 mm (2.7%) lowerthan the estimation (308.6 mm) which considers the eff ectsof both species composition and sapwood area. The maintree characteristics aff ecting stand transpiration are tree size(sapwood area) and dominance. Consideration of tree dominancewill signifi cantly improve stand transpiration estimationand provide a more solid basis for guiding integratedforest-water management at stand scale.
文摘It is well--known that broadlcaved/Korean pine forests distribute in the areanear the broad seas in the cast Asia.TheStudy history or the forests is coincided withthat of its exploitation and destroying.
基金supported by the National Natural Science Foundation of China(No.31971643)the Industry-University Cooperation Project of Fujian Science and Technology Department(Nos.2020N5008,2019N5009)+2 种基金the General program of Natural Science Foundation of Fujian Province of China(No.2018J01737)Special Funding Project of Fujian Provincial Department of Finance(SC-299)Minjiang Scholar Programme.
文摘Background:Carbon(C),nitrogen(N),and phosphorus(P)stoichiometry is a key indicator of nutrient utilization in plants,and C/N/P ratios are related to the life histories and adaptation strategies of tree species.However,no consensus has been reached on how leaf stoichiometric characteristics are affected by forest type and stand ages.The relationships between leaf stoichiometry and geographical,meteorological,and soil factors also remain poorly understood.Methods:Leaf and soil were sampled from forest stands of different age groups(young,middle-aged,near-mature,and mature)in two forest types(Chinese fir(Cunninghamia lanceolata)forests and evergreen broadleaved forests).The relationships between leaf C,N,and P stoichiometric parameters and geographical,meteorological,and soil factors were analysed by using redundancy analysis(RDA)and stepwise linear regression analysis.Results:Leaf C concentrations peaked in the near-mature stands with increasing age irrespective of forest type.Leaf N and P concentrations fluctuated with a rising trend in Chinese fir forests,while decreased first and increased later from young to mature phases in natural evergreen broadleaved forests.Chinese fir forests were primarily limited by N and P,while natural evergreen broadleaved forests were more susceptible to P limitation.Leaf C,N,and P stoichiometric characteristics in Chinese fir forests were mainly affected by the soil total P concentration(SP),longitude(LNG),growing season precipitation(GSP)and mean temperature in July(JUT).The leaf C concentration was mainly affected by GSP and JUT;leaf N and P concentrations were both positively correlated with LNG;and leaf P was positively correlated with SP.In evergreen broadleaved forests,however,leaf stoichiometric parameters displayed significant correlations with latitude(LAT)and mean annual precipitation(MAP).Conclusions:Leaf stoichiometry differed among forest stands of different age groups and forest types.Leaf C,N,and P stoichiometry was primarily explained by the combinations of SP,LNG,GSP and JUT in Chinese fir forests.LAT and MAP were the main controlling factors affecting the variations in the leaf C,N,and P status in natural evergreen broadleaved forests,which supports the temperature-plant physiological hypothesis.These findings improve the understanding of the distribution patterns and driving mechanisms of leaf stoichiometry linked with stand age and forest type.
基金financially supported by the"Programa de Mejoramiento del Profesorado"(project:Seguimiento y Evaluacion de Sitios Permanentes de Investigación Forestal y el Impacto Socioeconómico delManejo Forestal en Norte de México)supported by"Programa Banco Santander-USC"(becas para estancias predoctorales destinadas a docentes e investigadores de America Latina)
文摘Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variables as predictors.Methods:The data were obtained from 44 permanent plots used to monitor stand growth under forest management in the study area.Results:The generalized Bertalanffy-Richards model performed better than the other generalized models in predicting the total height of the species under study.For the genera Pinus and Quercus,the models were successfully calibrated by measuring the height of a subsample of three randomly selected trees close to the mean d,whereas for species of the genera Cupressus,Arbutus and Alnus,three trees were also selected,but they are specifically the maximum,minimum and mean d trees.Conclusions:The presented equations represent a new tool for the evaluation and management of natural forest in the region.
基金supported by the National Key Basic Research and Development Program of China (Grant No. G2000046801)the National Natural Science Foundation of China (Grant No. 30130060 )the A3 Foresight Program Project (NSFC)
文摘The biomass and productivity of Schima superba-Castanopsis carlesii forests in Tiantong,Zhejiang Province,were determined using overlapping quadrants and stem analyses.The total community biomass was(225.3±30.1) t hm-2,of which the aboveground parts accounted for 72.0% and the underground parts accounted for 28.0%.About 87.2% of biomass existed in the tree layer.The resprouting biomass was small,of which over 95.0% occurred in the shrub layer.The productivity of the aboveground parts of the community was(386.8±98.9) g m-2a-1,in which more than 96.0% was present at the tree level.The trunk's contribution to productivity was the greatest,while that of leaves was the smallest.In China,the community biomass of subtropical evergreen broadleaved forests differs significantly with the age of the forest.The community biomass of the 52-year-old S.superba-C.carlesii forests in this study was lower than the average biomass of subtropical evergreen broadleaved forests in China,and was lower than the biomass of other subtropical evergreen broadleaved forests elsewhere in the world.Moreover,its productivity was lower than the model estimate,indicating that without disturbance,this community has great developmental potential in terms of community biomass and productivity.