A 112 m×8 m sample pot which includes 14 sub-plots was set up along the slope in Hongshi Forestry Farm of Baihe Forestry Bureau (127°55′E, 42°30′ N), Jilin Province in August 2002. Community structure...A 112 m×8 m sample pot which includes 14 sub-plots was set up along the slope in Hongshi Forestry Farm of Baihe Forestry Bureau (127°55′E, 42°30′ N), Jilin Province in August 2002. Community structure, soil moisture contents at 0–10 cm and 10–20 cm in depth, water content of litter as well as the contents of C, N and P of litter, living leaves and branches in the broad-leaved/Korean pine (Pinus korraiensis) forest were measured in each sub-plot on different slope positions. The analytical results showed that there existed an obvious soil moisture gradient along the slope: upper slope <middle slope< lower slope. The difference in soil moisture contents on different positions of slope led to a change of the stand structure of the braod-leaved/Korean pine forest. The proportion ofQuercus mongolica gradually increased with the decrease of soil moisture content and that of other major tree species in the broad-leaved/Korean pine forest gradually decreased or disappeared. The dynamic of soil moisture contents in the litter layer was as same as that in mineral soils. The decomposition rates of the litter on different slope positions were different and the dry weights of existent litter varied significantly. The soil nutrients in the litter on the lower slope was richer than that on the upper slope due to the different stand structure on the different slope positions. The moisture content and nutrient contents of soil had effects on the composition, decomposition, and the nutrient release of litter, thus affecting stands growth and stand structure and finally leading to the change of ecosystem. Key words Soil moisture gradient - nutrient - Stand structure - Broad-leaved/Korean pine forest CLC number S718.5 Document code A Foundation item: This study was supported by the NKBRSF (G1999043407-1), Tackle Key Problem of Science and technology of China (2001BA510B-07), Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-406, SCXZD0101), NKTRDP (2001BA510B-07. 2002BA516A20).Biography: WANG Yan (1970-), female, Ph. D, associate professorResponsible editor: Song Funan展开更多
Soil nutrient concentrations in the top soils from two paddy terraces were determined in order to investigate spatial distributions of soil nutrients along the elevations on the Yunnan plateau of China during the fall...Soil nutrient concentrations in the top soils from two paddy terraces were determined in order to investigate spatial distributions of soil nutrients along the elevations on the Yunnan plateau of China during the fallow period.Results showed that soil nutrients in both terraces were higher than the reference concentrations except for SOC,TN,TP and Fe.Soil macronutrients didn't show significant differences in both terraces except for Mg and Ca,so did soil micronutrients except for Mn.Spatial distribution patterns of soil nutrients along the increasing elevations were different in both terraces.However,soil nutrients in both terraces were generally not significantly influenced by the elevations and soil pH values.The findings of this study can contribute to soil fertility management and ecological protection of Hani terraces.展开更多
Aims Functional traits are usually used to predict plant demographic rates without considering environmental contexts.However,previous studies have consistently found that traits have low explanatory power for plant d...Aims Functional traits are usually used to predict plant demographic rates without considering environmental contexts.However,previous studies have consistently found that traits have low explanatory power for plant demographic rates.We hypothesized that accounting for environmental contexts instead of focusing on traits alone could improve our understanding of how traits influence plant demographic rates.Methods We used generalized linear mixed-effect models to analyse the effects of functional traits(related to leaf,stem,seed and whole plant),environmental gradients(soil nutrients,water and elevation)and their interactions on the survival dynamics of 14133 saplings and 3289 adults in a 9-ha old-growth temperate forest plot.Important Findings We found that environmental variables,neighbour crowding and traits alone(i.e.main effects)influenced plant survival.However,the effects of the latter two variables varied between saplings and adults.The trait–environment interactions influenced plant survival,such that resource conservative traits increased plant survival under harsh conditions but decreased survival under mild conditions.The elevational gradient was the most important environmental factor driving these effects in our plot.Our results support the hypothesis that functional traits influence plant survival depending on environmental contexts in local communities.These results also imply that one species with limited trait variation cannot occupy all environments,which can promote species diversity.展开更多
基金This study was supported by the NKBRSF (G1999043407-1) Tackle Key Problem of Science and technology of China (2001BA510B-07) Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-406SCXZD0101)NKTRDP (2001BA510B
文摘A 112 m×8 m sample pot which includes 14 sub-plots was set up along the slope in Hongshi Forestry Farm of Baihe Forestry Bureau (127°55′E, 42°30′ N), Jilin Province in August 2002. Community structure, soil moisture contents at 0–10 cm and 10–20 cm in depth, water content of litter as well as the contents of C, N and P of litter, living leaves and branches in the broad-leaved/Korean pine (Pinus korraiensis) forest were measured in each sub-plot on different slope positions. The analytical results showed that there existed an obvious soil moisture gradient along the slope: upper slope <middle slope< lower slope. The difference in soil moisture contents on different positions of slope led to a change of the stand structure of the braod-leaved/Korean pine forest. The proportion ofQuercus mongolica gradually increased with the decrease of soil moisture content and that of other major tree species in the broad-leaved/Korean pine forest gradually decreased or disappeared. The dynamic of soil moisture contents in the litter layer was as same as that in mineral soils. The decomposition rates of the litter on different slope positions were different and the dry weights of existent litter varied significantly. The soil nutrients in the litter on the lower slope was richer than that on the upper slope due to the different stand structure on the different slope positions. The moisture content and nutrient contents of soil had effects on the composition, decomposition, and the nutrient release of litter, thus affecting stands growth and stand structure and finally leading to the change of ecosystem. Key words Soil moisture gradient - nutrient - Stand structure - Broad-leaved/Korean pine forest CLC number S718.5 Document code A Foundation item: This study was supported by the NKBRSF (G1999043407-1), Tackle Key Problem of Science and technology of China (2001BA510B-07), Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-406, SCXZD0101), NKTRDP (2001BA510B-07. 2002BA516A20).Biography: WANG Yan (1970-), female, Ph. D, associate professorResponsible editor: Song Funan
基金supported by National Basic Research Program (Grant No.2010CB951102)National Natural Science Foundation of China (Grant No.50879005,40701003 and U0833002)+2 种基金Program for New Century Excellent Talents in UniversityProgram for Changjiang Scholars and Innovative Research Team in University (Grant no.IRT0809)the Fundamental Research Funds for the Central Universities (Grant No.2009SD-24)
文摘Soil nutrient concentrations in the top soils from two paddy terraces were determined in order to investigate spatial distributions of soil nutrients along the elevations on the Yunnan plateau of China during the fallow period.Results showed that soil nutrients in both terraces were higher than the reference concentrations except for SOC,TN,TP and Fe.Soil macronutrients didn't show significant differences in both terraces except for Mg and Ca,so did soil micronutrients except for Mn.Spatial distribution patterns of soil nutrients along the increasing elevations were different in both terraces.However,soil nutrients in both terraces were generally not significantly influenced by the elevations and soil pH values.The findings of this study can contribute to soil fertility management and ecological protection of Hani terraces.
基金This study was financially supported by the NationalNatural Science Foundation of China(31870399,32071533)the Strategic Priority ResearchProgram of the Chinese Academy of Sciences(XDB31030000).
文摘Aims Functional traits are usually used to predict plant demographic rates without considering environmental contexts.However,previous studies have consistently found that traits have low explanatory power for plant demographic rates.We hypothesized that accounting for environmental contexts instead of focusing on traits alone could improve our understanding of how traits influence plant demographic rates.Methods We used generalized linear mixed-effect models to analyse the effects of functional traits(related to leaf,stem,seed and whole plant),environmental gradients(soil nutrients,water and elevation)and their interactions on the survival dynamics of 14133 saplings and 3289 adults in a 9-ha old-growth temperate forest plot.Important Findings We found that environmental variables,neighbour crowding and traits alone(i.e.main effects)influenced plant survival.However,the effects of the latter two variables varied between saplings and adults.The trait–environment interactions influenced plant survival,such that resource conservative traits increased plant survival under harsh conditions but decreased survival under mild conditions.The elevational gradient was the most important environmental factor driving these effects in our plot.Our results support the hypothesis that functional traits influence plant survival depending on environmental contexts in local communities.These results also imply that one species with limited trait variation cannot occupy all environments,which can promote species diversity.