Based on the analysis of the current situation of Chinese forestry and a series of ecological, environmental, eco-nomic, and social problems, this paper emphasized on the importance of forests in social and economic d...Based on the analysis of the current situation of Chinese forestry and a series of ecological, environmental, eco-nomic, and social problems, this paper emphasized on the importance of forests in social and economic development in China The author pointed out that sustainable development, particularly the sustainable development of forestry, is the inevitable choice to solve the problems of ecological environment and social economics. The objectives, criteria, and strategies of sus-taining forestry were also demonstrated and expounded, from the viewpoints of ecology, economics, and sociology.展开更多
The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to resea...The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to research enterprises' competition problems .explains the ecological characterisiics of enterprises' competition, such as non-symmetry, crowded effect, density effect. competition-rejective effect, suitable resources niche and red queen effect etc., deduces the ecological model of enterprise' competition, and further analyzes enterprises' competition strategy; strategy R and strategy K. on the basis of enterprises' practices, Therefore enterprises' competition ecosystem theories have further been deepened and enriched.展开更多
Based on the field survey of the traditional village in Shanggantang,Hunan province,P.R.China,we analyzed ecological strategies in aspects of the whole human habitation environment and vernacular building human habita...Based on the field survey of the traditional village in Shanggantang,Hunan province,P.R.China,we analyzed ecological strategies in aspects of the whole human habitation environment and vernacular building human habitation environment.The ecological strategies included adapting to the local climate,reducing source consumption,utilizing local materials and so on.The research is to provide a reference to practice and theoretical development of eco-folk houses in the area.展开更多
Recently, the increasing concern about the environmental quality of human settlements makes people realize that the attractive environment given by natural ecology also deficiently needs the feedback and protection of...Recently, the increasing concern about the environmental quality of human settlements makes people realize that the attractive environment given by natural ecology also deficiently needs the feedback and protection of nature in some forms so that the natural ecology can be endlessly cycled on its own. Taking the project of German Enterprise Center in Qingdao Sino-German Ecopark as an example, this paper discussed construction of outdoor environment water circulation system using the landscape building method.展开更多
To conduct the ecological restoration and reconstruction of disaster areas after the severe earthquake, such as Wenchuan Earthquake and Lushan Earthquake, this article uses region al ecological environment evaluation ...To conduct the ecological restoration and reconstruction of disaster areas after the severe earthquake, such as Wenchuan Earthquake and Lushan Earthquake, this article uses region al ecological environment evaluation and ecological footprint to construct a quantitative analysis model on the basis of ecololgical environment indexes in Mianzhu City. Through this model, resource status of the regional environment in Mianzhu is analyzed, as well as the ecological capacity and the ecological security. Based on the evaluation and analysis, this paper provides multi-path development strategies of ecological restoration and sustainable development of human settlements after the earthquake.展开更多
Global climate change has led to the decline of species and functional diversity in ecosystems,changing community composition and ecosystem functions.However,we still know little about how species with different resou...Global climate change has led to the decline of species and functional diversity in ecosystems,changing community composition and ecosystem functions.However,we still know little about how species with different resource-use strategies(different types of resource usage and plant growth of plants as indicated by the spectrum of plant economic traits,including acquisitive resource-use strategy and conservative resource-use strategy)would change in response to climate change,and how the changes in the diversity of species with different resource-use strategies may influence community-level productivity.Here,using long-term(1982–2017)observatory data in a temperate grassland in Inner Mongolia,we investigated how climate change had affected the species richness(SR)and functional richness(FRic)for the whole community and for species with different resource-use strategies.Specifically,based on data for four traits representing leaf economics spectrum(leaf carbon concentration,leaf nitrogen concentration,leaf phosphorus concentration,and specific leaf area),we divided 81 plant species appearing in the grassland community into three plant functional types representing resource-acquisitive,medium,and resource-conservative species.We then analyzed the changes in community-level productivity in response to the decline of SR and FRic at the community level and for different resource-use strategies.We found that community-level SR and FRic decreased with drying climate,which was largely driven by the decline of diversity for resource-acquisitive species.However,community-level productivity remained stable because resource-conservative species dominating this grassland were barely affected by climate change.Our study revealed distinctive responses of species with different resource-use strategies to climate change and provided a new approach based on species functional traits for predicting the magnitude and direction of climate change effects on ecosystem functions.展开更多
The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species diff...The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species differ both in their morphology and physiology,resulting in a change in the ratio of male to female plants depending on the environment.To further explore the functional traits critical to this sex-based distinctive response in the alpine grassland,we have surveyed the sex ratios,measured their photosynthetic parameters,height,leaf area and biomass allocation.The results showed that(i)The males had higher Pn,light saturation point,apparent quantum efficiency,A_(max) and lower water-use efficiency(WUE),which exhibited higher utilization efficiency or tolerance to strong light,while the females indicated higher utilization efficiency for low light and water.And it showed sex-specific biomass allocation patterns.(ii)H.rhamnoides populations across the successional stages all showed a male-biased sexual allocation,which was closely related to sex-specific WUE,Pn,root biomass/total biomass and root-crown ratio.(iii)The leaf traits of H.rhamnoides changed from higher N_(area),P_(area) and leaf mass per area in the early and late to lower in the middle,which meant they moved their growth strategy from resource rapid acquisition to conservation as the succession progressed.(iv)The increasing soil total phosphorus mostly contributed to regulating the sex bias of populations and variations of traits during the succession.The results are vital for the management of grassland degradation and restoration due to shrub encroachment on the QTP.展开更多
Taking annual plant Eragrostis poaeides in the artificial vegetation-stabilized sand dune in the Shapotou Experimental Research Station as example, study has been done on the adaptation strategies of annual plants to ...Taking annual plant Eragrostis poaeides in the artificial vegetation-stabilized sand dune in the Shapotou Experimental Research Station as example, study has been done on the adaptation strategies of annual plants to random environment through fixed quadrat observations of population changes and fixed plant determinations of individual growth, seed germination,population dynamics, spatial distribution pattern of population, competition and regulation. During the growing season, the survival rate of annual plants depends on the precipitation intensity and precipitation duration which activate the germination of seeds. The optimal germination strategy of annual plants in this habitat during the growing season appears as continuous germination under suitable conditions. Such continuous germination is an adaptive characteristic of annual plants to random environment. In addition, the variation processes of population size and regulation mechanism of E. poaeoides are studied. Statistical results of natural population in four consecutive years show that water condition in the habitat is the leading factor affecting the population dynamics of E. poaeoides. During the establishment period E. poaeoides had a higher death rate, but in the middle to later period they could survive stably. Due to the limitation of soil moisture, the competition among individuals for water inevitably led to self-thinning phenomena. Under very arid condition, the survival curve of annual herbs entirely appears as Deevey Ⅲ type (C type), but under relatively adequate precipitation condition, the survival curve appears as intermediate type. The strategy of life history obviously appears as r-strategy. Plant species of r-strategy often occurs in the early succession stage of the communities. In the relatively adequate and evenly-distributed rainfall years, E. poaeoides population exhibited a density-dependent, i. e., survival rate increased with decrease in population density. The main pattern to regulate the population number for the intraspecific competition is to regulate the highly variable initial density into a final density with narrow variation range.展开更多
Development of Xiong'an New District(XND) is integral to the implementation of the Beijing-Tianjin-Hebei(BTH) Integration Initiative. It is intended to ease the non-capital functions of Beijing, optimize regional ...Development of Xiong'an New District(XND) is integral to the implementation of the Beijing-Tianjin-Hebei(BTH) Integration Initiative. It is intended to ease the non-capital functions of Beijing, optimize regional spatial patterns, and enhance ecosystem services and living environment in this urban agglomeration. Applying multi-stage remote sensing(RS) images, land use/cover change(LUCC) data, ecosystem services assessment data, and high-precision urban land-cover information, we reveal the regional land-cover characteristics of this new district as well as across the planned area of the entire BTH urban agglomeration. Corresponding ecological protection and management strategies are also proposed. Results indicated that built-up areas were rapidly expanding, leading to a continuous impervious surface at high density. Urban and impervious surface areas(ISAs) grew at rates 1.27 and 1.43 times higher than that in the 2000 s, respectively, seriously affecting about 15% area of the sub-basins. Construction of XND mainly encompasses Xiongxian, Rongcheng, and Anxin counties, areas which predominantly comprise farmland, townships and rural settlements, water, and wetland ecosystems. The development and construction of XND should ease the non-capital functions of Beijing, as well as moderately control population and industrial growth. Thus, this development should be included within the national ‘sponge city' construction pilot area in early planning stages, and reference should be made to international low-impact development modes in order to strengthen urban green infrastructural construction. Early stage planning based on the existing characteristics of the underlying surface should consider the construction of green ecological patches and ecological corridors between XND and the cities of Baoding, Beijing, and Tianjin. The proportion of impervious surfaces should not exceed 60%, while that of the core area should not exceed 70%. The development of XND needs to initiate the concept of ‘planning a city according to water resource amount' and incorporate rainwater collection and recycling.展开更多
Aims Ecological strategies related to the adaptation of plants to environmental stress have long been studied by ecologists,but few studies have systematically revealed the ecological process of plant adaptation to he...Aims Ecological strategies related to the adaptation of plants to environmental stress have long been studied by ecologists,but few studies have systematically revealed the ecological process of plant adaptation to herbivores as a whole.Methods In this study,Stipa breviflora,the dominant species in the desert steppe of Inner Mongolia,was used to analyse its reproductive individual characteristics and seed traits as well as the soil seed bank and spatial patterns under heavy-grazing and no-grazing treatments.Important Findings The results showed that the number of reproductive branches positively affected the number of vegetative branches.The analysis of the soil seed bank showed that the density of S.breviflora seeds beneath reproductive S.breviflora individuals was significantly higher than that in bare land.The seed density was also significantly negatively correlated with the seed characteristics and the soil seed bank in bare land.The spatial distribution of S.breviflora was aggregated under heavy grazing.Our results suggest that under heavy grazing,reproductive activity plays a key role in resource allocation.Stipa breviflora evolved the ecological strategy of nearby diffusion by regulating the morphological characteristics of the seeds,which promotes a positive spatial correlation between the juvenile and adult populations at a small scale,thus leading to the formation of‘safe islands’.展开更多
Aims Understanding variation and coordination of leaf traits at multiscales along elevational gradients can help predict the likely responses of dominant species to climate change.We seek to determine the extent to wh...Aims Understanding variation and coordination of leaf traits at multiscales along elevational gradients can help predict the likely responses of dominant species to climate change.We seek to determine the extent to which variation in leaf stomatal,anatomical and morphological traits is associated with environmental factors,and whether ecological strategies of Cyclobalanopsis species shift with elevations.Methods In a tropical forest landscape in Jianfengling,South China,we determined leaf traits related to stomata,anatomy and morphology of six evergreen oak species(Cyclobalanopsis bambusaefolia,C.hui,C.patelliformis,C.fleuryi,C.tiaoloshanica and C.phanera)along a long elevational gradient(400–1400 m above sea level).Important Findings We found that stomatal density and stomatal pore index increased,whereas spongy mesophyll thickness to leaf thickness ratios decreased,significantly with elevation.The leaf area and leaf dry matter content increased and decreased,respectively,with elevation.Variations in stomatal,anatomical and morphological traits were mainly correlated to the mean annual temperature,mean annual sum precipitation and soil pH.At low and high elevations,the oak species exhibited strong stress tolerance combined with competition strategy,while they shifted toward more clearly the competitive strategy at intermediate elevations.And the changes in soil phosphorus concentration and soil pH along the elevation may drive the shift of ecological strategy.The results showed that the dominant oak species in tropical forests respond to environmental change by modulating traits at multiple levels,from that of the individual cell,through tissue and up to the whole leaf scale.展开更多
Aims Despite the growing interest in the topic of functional ecology,there are still forest regions that have not been examined,as most work has been done in the tropics.unresolved issues include the strength of a gro...Aims Despite the growing interest in the topic of functional ecology,there are still forest regions that have not been examined,as most work has been done in the tropics.unresolved issues include the strength of a growth-mortality trade-off in trees(originally identified for seedlings)and the nature of the association between plant traits and vital rates,if any.our objectives were to examine whether(i)ecological strategies in south american mixed forests are organ-ized along the fast competitor×slow stress-tolerator and height gradients as the main strategy axes depicted in the overall trait and vital rate correlation structure,and(ii)a tentative path model we proposed can explain the patterns of covariation among traits and vital rates.Methods We studied a different habitat(subtropical mixed conifer-hardwood forests)and region(brazilian atlantic Forest)from the majority of related studies in forests,carried out in the Neotropical region.Data on total height,stem slenderness,crown depth,wood density,specific leaf area,leaf and seed length,seed dispersal mode,annual mortality,diameter relative growth rate and relative growth rate under favorable conditions were measured in southern brazil for 66 tree species.Data were subjected to principal components analysis and path analysis.restricted data on saplings and treelets were analyzed through correlation.Important Findingsstudied traits were reduced to four principal components.Principal components analysis produced axes that fit the resource acquisition versus resource-conservation and the height-mortality trade-offs,although the former was split into two distinct axes.seed size and seed dispersal mode appeared independently of these axes.a path model showed that leaf length and specific leaf area caused direct changes in trunk slenderness and,indirectly through growth,affected mortality.Expected trade-offs between growth and survivorship and between wood density and stem slenderness trade-offs were not found.this may result from the lack of extreme pioneers and over-representation of slow-growing hardwood species found in atlantic subtropical forests of south america.this suggests that the fastest growing species in the region do not grow so fast as to compromise wood density and survivorship,but grow fast enough to benefit from increased size.relationships between traits and vital rates seem to be mediated by the assembly process of regional floras,and the relative importance of traits like SLA and wood density may vary between floristic regions.展开更多
基金This paper was supported by the National Natural Science Foundation of China (No. 79930800) and Knowledge Innovation Programme of Chinese Academy of Sciences
文摘Based on the analysis of the current situation of Chinese forestry and a series of ecological, environmental, eco-nomic, and social problems, this paper emphasized on the importance of forests in social and economic development in China The author pointed out that sustainable development, particularly the sustainable development of forestry, is the inevitable choice to solve the problems of ecological environment and social economics. The objectives, criteria, and strategies of sus-taining forestry were also demonstrated and expounded, from the viewpoints of ecology, economics, and sociology.
基金Supported by Hunan Judge Committee of Philosophy and Social Science(No.0402003)and Research Item of Hainan University(No.Kyjj0409).
文摘The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to research enterprises' competition problems .explains the ecological characterisiics of enterprises' competition, such as non-symmetry, crowded effect, density effect. competition-rejective effect, suitable resources niche and red queen effect etc., deduces the ecological model of enterprise' competition, and further analyzes enterprises' competition strategy; strategy R and strategy K. on the basis of enterprises' practices, Therefore enterprises' competition ecosystem theories have further been deepened and enriched.
基金Funded by the Science and Technology Research Foundation of Hunan Government(No.08jj3106)
文摘Based on the field survey of the traditional village in Shanggantang,Hunan province,P.R.China,we analyzed ecological strategies in aspects of the whole human habitation environment and vernacular building human habitation environment.The ecological strategies included adapting to the local climate,reducing source consumption,utilizing local materials and so on.The research is to provide a reference to practice and theoretical development of eco-folk houses in the area.
基金Sponsored by the National Science and Technology Project in the Twelfth Five-Year Plan Period(2013BAJ02B04)
文摘Recently, the increasing concern about the environmental quality of human settlements makes people realize that the attractive environment given by natural ecology also deficiently needs the feedback and protection of nature in some forms so that the natural ecology can be endlessly cycled on its own. Taking the project of German Enterprise Center in Qingdao Sino-German Ecopark as an example, this paper discussed construction of outdoor environment water circulation system using the landscape building method.
基金Sponsored by the National Natural Science Fund(51208428)The Basic Research Plan Project of Sichuan Province(2013JY0038)+1 种基金Research project of Sichuan Province Education Office(JGYQ201419)The Fundamental Research Funds for the Central Universities of Science and Technology Innovation Project(SWJTU11CX158)
文摘To conduct the ecological restoration and reconstruction of disaster areas after the severe earthquake, such as Wenchuan Earthquake and Lushan Earthquake, this article uses region al ecological environment evaluation and ecological footprint to construct a quantitative analysis model on the basis of ecololgical environment indexes in Mianzhu City. Through this model, resource status of the regional environment in Mianzhu is analyzed, as well as the ecological capacity and the ecological security. Based on the evaluation and analysis, this paper provides multi-path development strategies of ecological restoration and sustainable development of human settlements after the earthquake.
基金supported by the National Natural Science Foundation of China(32125026,31988102)the National Key Research Development Program of China(2022YFF0802300)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB31000000)。
文摘Global climate change has led to the decline of species and functional diversity in ecosystems,changing community composition and ecosystem functions.However,we still know little about how species with different resource-use strategies(different types of resource usage and plant growth of plants as indicated by the spectrum of plant economic traits,including acquisitive resource-use strategy and conservative resource-use strategy)would change in response to climate change,and how the changes in the diversity of species with different resource-use strategies may influence community-level productivity.Here,using long-term(1982–2017)observatory data in a temperate grassland in Inner Mongolia,we investigated how climate change had affected the species richness(SR)and functional richness(FRic)for the whole community and for species with different resource-use strategies.Specifically,based on data for four traits representing leaf economics spectrum(leaf carbon concentration,leaf nitrogen concentration,leaf phosphorus concentration,and specific leaf area),we divided 81 plant species appearing in the grassland community into three plant functional types representing resource-acquisitive,medium,and resource-conservative species.We then analyzed the changes in community-level productivity in response to the decline of SR and FRic at the community level and for different resource-use strategies.We found that community-level SR and FRic decreased with drying climate,which was largely driven by the decline of diversity for resource-acquisitive species.However,community-level productivity remained stable because resource-conservative species dominating this grassland were barely affected by climate change.Our study revealed distinctive responses of species with different resource-use strategies to climate change and provided a new approach based on species functional traits for predicting the magnitude and direction of climate change effects on ecosystem functions.
基金supported by National Natural Science Foundation of China(32201525)the Gansu province’s Key Research and Development Plan(21YF5NA069)+2 种基金the Longyuan Talent Youth Innovation and Entrepreneurship Team projectthe Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education(YDZX20216200001007)the Foreign Expert Introduction Special Project of Gansu Province(22JR10KA010).
文摘The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species differ both in their morphology and physiology,resulting in a change in the ratio of male to female plants depending on the environment.To further explore the functional traits critical to this sex-based distinctive response in the alpine grassland,we have surveyed the sex ratios,measured their photosynthetic parameters,height,leaf area and biomass allocation.The results showed that(i)The males had higher Pn,light saturation point,apparent quantum efficiency,A_(max) and lower water-use efficiency(WUE),which exhibited higher utilization efficiency or tolerance to strong light,while the females indicated higher utilization efficiency for low light and water.And it showed sex-specific biomass allocation patterns.(ii)H.rhamnoides populations across the successional stages all showed a male-biased sexual allocation,which was closely related to sex-specific WUE,Pn,root biomass/total biomass and root-crown ratio.(iii)The leaf traits of H.rhamnoides changed from higher N_(area),P_(area) and leaf mass per area in the early and late to lower in the middle,which meant they moved their growth strategy from resource rapid acquisition to conservation as the succession progressed.(iv)The increasing soil total phosphorus mostly contributed to regulating the sex bias of populations and variations of traits during the succession.The results are vital for the management of grassland degradation and restoration due to shrub encroachment on the QTP.
基金supported by the National Natural Science Foundation of China(Grant No.90202015)Innovation Study Project from Chinese Academy of Sciences(Grant Nos.KZCX3-SW-324,KZCX1-09)State Key Project for Basic Research"the Process of Desertification and Its Control in the Northern China"(Grant No.G2000048704).
文摘Taking annual plant Eragrostis poaeides in the artificial vegetation-stabilized sand dune in the Shapotou Experimental Research Station as example, study has been done on the adaptation strategies of annual plants to random environment through fixed quadrat observations of population changes and fixed plant determinations of individual growth, seed germination,population dynamics, spatial distribution pattern of population, competition and regulation. During the growing season, the survival rate of annual plants depends on the precipitation intensity and precipitation duration which activate the germination of seeds. The optimal germination strategy of annual plants in this habitat during the growing season appears as continuous germination under suitable conditions. Such continuous germination is an adaptive characteristic of annual plants to random environment. In addition, the variation processes of population size and regulation mechanism of E. poaeoides are studied. Statistical results of natural population in four consecutive years show that water condition in the habitat is the leading factor affecting the population dynamics of E. poaeoides. During the establishment period E. poaeoides had a higher death rate, but in the middle to later period they could survive stably. Due to the limitation of soil moisture, the competition among individuals for water inevitably led to self-thinning phenomena. Under very arid condition, the survival curve of annual herbs entirely appears as Deevey Ⅲ type (C type), but under relatively adequate precipitation condition, the survival curve appears as intermediate type. The strategy of life history obviously appears as r-strategy. Plant species of r-strategy often occurs in the early succession stage of the communities. In the relatively adequate and evenly-distributed rainfall years, E. poaeoides population exhibited a density-dependent, i. e., survival rate increased with decrease in population density. The main pattern to regulate the population number for the intraspecific competition is to regulate the highly variable initial density into a final density with narrow variation range.
基金Key Project of Beijing Natural Science Foundation,No.8171004
文摘Development of Xiong'an New District(XND) is integral to the implementation of the Beijing-Tianjin-Hebei(BTH) Integration Initiative. It is intended to ease the non-capital functions of Beijing, optimize regional spatial patterns, and enhance ecosystem services and living environment in this urban agglomeration. Applying multi-stage remote sensing(RS) images, land use/cover change(LUCC) data, ecosystem services assessment data, and high-precision urban land-cover information, we reveal the regional land-cover characteristics of this new district as well as across the planned area of the entire BTH urban agglomeration. Corresponding ecological protection and management strategies are also proposed. Results indicated that built-up areas were rapidly expanding, leading to a continuous impervious surface at high density. Urban and impervious surface areas(ISAs) grew at rates 1.27 and 1.43 times higher than that in the 2000 s, respectively, seriously affecting about 15% area of the sub-basins. Construction of XND mainly encompasses Xiongxian, Rongcheng, and Anxin counties, areas which predominantly comprise farmland, townships and rural settlements, water, and wetland ecosystems. The development and construction of XND should ease the non-capital functions of Beijing, as well as moderately control population and industrial growth. Thus, this development should be included within the national ‘sponge city' construction pilot area in early planning stages, and reference should be made to international low-impact development modes in order to strengthen urban green infrastructural construction. Early stage planning based on the existing characteristics of the underlying surface should consider the construction of green ecological patches and ecological corridors between XND and the cities of Baoding, Beijing, and Tianjin. The proportion of impervious surfaces should not exceed 60%, while that of the core area should not exceed 70%. The development of XND needs to initiate the concept of ‘planning a city according to water resource amount' and incorporate rainwater collection and recycling.
基金supported by the Qinghai Provincial Key R&D Program in Qinghai Province(2019-SF-145)the Platform of the Adaptive Management of the Alpine Grassland-livestock System(2020-ZJ-T07)+1 种基金the Natural Science Foundation for Young Scientists of Qinghai Province(2018-ZJ-939Q)the National Natural Science Foundation of China(31460126,3177131141).
文摘Aims Ecological strategies related to the adaptation of plants to environmental stress have long been studied by ecologists,but few studies have systematically revealed the ecological process of plant adaptation to herbivores as a whole.Methods In this study,Stipa breviflora,the dominant species in the desert steppe of Inner Mongolia,was used to analyse its reproductive individual characteristics and seed traits as well as the soil seed bank and spatial patterns under heavy-grazing and no-grazing treatments.Important Findings The results showed that the number of reproductive branches positively affected the number of vegetative branches.The analysis of the soil seed bank showed that the density of S.breviflora seeds beneath reproductive S.breviflora individuals was significantly higher than that in bare land.The seed density was also significantly negatively correlated with the seed characteristics and the soil seed bank in bare land.The spatial distribution of S.breviflora was aggregated under heavy grazing.Our results suggest that under heavy grazing,reproductive activity plays a key role in resource allocation.Stipa breviflora evolved the ecological strategy of nearby diffusion by regulating the morphological characteristics of the seeds,which promotes a positive spatial correlation between the juvenile and adult populations at a small scale,thus leading to the formation of‘safe islands’.
基金This work was jointly supported by the National Natural Science Foundation of China(41771522 and 41773071)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(GML2019ZD0408)+1 种基金the Biological Resources Service Network Initiative of Chinese Academy of Sciences(ZSSD-007)the Youth Innovation Promotion Association of CAS.
文摘Aims Understanding variation and coordination of leaf traits at multiscales along elevational gradients can help predict the likely responses of dominant species to climate change.We seek to determine the extent to which variation in leaf stomatal,anatomical and morphological traits is associated with environmental factors,and whether ecological strategies of Cyclobalanopsis species shift with elevations.Methods In a tropical forest landscape in Jianfengling,South China,we determined leaf traits related to stomata,anatomy and morphology of six evergreen oak species(Cyclobalanopsis bambusaefolia,C.hui,C.patelliformis,C.fleuryi,C.tiaoloshanica and C.phanera)along a long elevational gradient(400–1400 m above sea level).Important Findings We found that stomatal density and stomatal pore index increased,whereas spongy mesophyll thickness to leaf thickness ratios decreased,significantly with elevation.The leaf area and leaf dry matter content increased and decreased,respectively,with elevation.Variations in stomatal,anatomical and morphological traits were mainly correlated to the mean annual temperature,mean annual sum precipitation and soil pH.At low and high elevations,the oak species exhibited strong stress tolerance combined with competition strategy,while they shifted toward more clearly the competitive strategy at intermediate elevations.And the changes in soil phosphorus concentration and soil pH along the elevation may drive the shift of ecological strategy.The results showed that the dominant oak species in tropical forests respond to environmental change by modulating traits at multiple levels,from that of the individual cell,through tissue and up to the whole leaf scale.
基金Funding was provided by the Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq)through the grant‘PELD-Bioma Araucária e suas Transições’and by Energética Barra Grande(BAESA).
文摘Aims Despite the growing interest in the topic of functional ecology,there are still forest regions that have not been examined,as most work has been done in the tropics.unresolved issues include the strength of a growth-mortality trade-off in trees(originally identified for seedlings)and the nature of the association between plant traits and vital rates,if any.our objectives were to examine whether(i)ecological strategies in south american mixed forests are organ-ized along the fast competitor×slow stress-tolerator and height gradients as the main strategy axes depicted in the overall trait and vital rate correlation structure,and(ii)a tentative path model we proposed can explain the patterns of covariation among traits and vital rates.Methods We studied a different habitat(subtropical mixed conifer-hardwood forests)and region(brazilian atlantic Forest)from the majority of related studies in forests,carried out in the Neotropical region.Data on total height,stem slenderness,crown depth,wood density,specific leaf area,leaf and seed length,seed dispersal mode,annual mortality,diameter relative growth rate and relative growth rate under favorable conditions were measured in southern brazil for 66 tree species.Data were subjected to principal components analysis and path analysis.restricted data on saplings and treelets were analyzed through correlation.Important Findingsstudied traits were reduced to four principal components.Principal components analysis produced axes that fit the resource acquisition versus resource-conservation and the height-mortality trade-offs,although the former was split into two distinct axes.seed size and seed dispersal mode appeared independently of these axes.a path model showed that leaf length and specific leaf area caused direct changes in trunk slenderness and,indirectly through growth,affected mortality.Expected trade-offs between growth and survivorship and between wood density and stem slenderness trade-offs were not found.this may result from the lack of extreme pioneers and over-representation of slow-growing hardwood species found in atlantic subtropical forests of south america.this suggests that the fastest growing species in the region do not grow so fast as to compromise wood density and survivorship,but grow fast enough to benefit from increased size.relationships between traits and vital rates seem to be mediated by the assembly process of regional floras,and the relative importance of traits like SLA and wood density may vary between floristic regions.