In the lack of extreme pioneers:trait relationships and ecological strategies of 66 subtropical tree species

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.

Research on the Regional Ecological Environment Evaluation and Application under the Influence of the Severe Earthquake Disaster

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.

Heart of Landscape and Contribution of Building Environment: Discussions about Landscape Construction of Outdoor Environment Water Circulation System

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.

Climate change filtered out resource-acquisitive plants in a temperate grassland in Inner Mongolia,China

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.