Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increm...Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increment as well as allometric functions in a karst evergreen and deciduous broadleaved mixed forest in central Guizhou Province, southwestern China. Results showed that the ANPP increased from 1961 to 2015, especially during the last 20–30 years, but with strong variations. The deciduous tree had higher ANPP than the evergreen tree according to two kinds of estimates by the tree ring and girth increment. The averaged ANPP for these two mature trees was 2.27 kg/individual/year, ca. 8 t/ha/year considering the normal stand density. Such karst forest productivity was lower than the natural subtropical forests in China and in the world.展开更多
According to archaeological investigation and preliminary excavation, the Yangjia Site, located in the northern Taihu Lake region, at Wuxi City, Jiangsu Province, is a Neolithic archaeological site dominated by cultur...According to archaeological investigation and preliminary excavation, the Yangjia Site, located in the northern Taihu Lake region, at Wuxi City, Jiangsu Province, is a Neolithic archaeological site dominated by cultural remains attributed to the late Majiabang Culture(6270–5920 cal. a BP). Here a systematic archaeobotanical study was conducted to investigate vegetation landscape, environmental characteristics and rice agriculture in the prehistoric northern Taihu Lake area. The abundance, frequency and standard density of charred rice were the highest of all of the remains of the seed plants unearthed. In addition, a variety of wetland weeds, such as Haloragaceae, Cyperaceae, Carex sp., and Oxalis corniculata, were found. Pollen and phytoliths recorded that the evergreen-deciduous broadleaf mixed forest(represented by Quercus and Castanopsis) tends to decrease, while Poaceae was the most significant of the terrestrial herbs, water area expanded and water activities strengthened, indicating generally warm and humid conditions at the Yangjia Site during the late Majiabang Culture. All indicators of pollen, phytolith and macro-plant remains suggest that wild rice should be once distributed at or around the site before human occupation, after which rice agriculture progressed rapidly during the late Majiabang Culture.展开更多
Aims The relationships between plant species and soil microorganisms remain indeterminable in different ecosystems worldwide.In karst ecosystems,soil microbial(SM)community structure and their environmental driving fa...Aims The relationships between plant species and soil microorganisms remain indeterminable in different ecosystems worldwide.In karst ecosystems,soil microbial(SM)community structure and their environmental driving factors are poorly explored,and the relationships between plant species and soil microorganisms are unclear.This study aimed to characterize the general patterns of SM community composition and biomass,and to explore the specific tree species and soil physiochemical properties highly related to SM community diversity and biomass in a karst forest.Methods The effects of tree species on SM community composition and biomass were firstly investigated on the basis of 212 soil samples collected from five dominant tree species(Lithocarpus confinis Huang,Platycarya longipes Wu,Itea yunnanensis Franch.,Machilus cavaleriei H.Lév.and Carpinus pubescens Burkill)through phospholipid fatty acid(PLFA)analysis of a karst evergreen and deciduous broad-leaved mixed forest in central Guizhou Province,southwestern China.The relationships between SM community structure and tree species and soil physiochemical properties were statistically analysed.Important Findings A total of 132 SM-PLFA biomarkers were detected.The average number of SM-PLFA biomarkers and microbial biomass in each soil sample were 65.97 and 11.22µg g^(–1),respectively.Tree species influenced the number of SM-PLFA biomarkers but not the SM biomass.The number of SM-PLFA biomarkers of C.pubescens was significantly higher than that of other species(P<0.05);the numbers of SM-PLFA biomarkers amongst other species showed no significant difference.Microbial biomass showed no relationships with the soil physiochemical properties of nutrient-rich surface soils but positively correlated(P<0.05)with soil organic carbon,nitrogen and phosphorus concentrations in deeper soils.The karst forest in the plateau-surface terrain of central Guizhou Province presented a low fungal-to-bacterial ratio,low microbial biomass storage and high microbial community diversity.Specific tree species affect the SM community diversity in this kind of karst forest.展开更多
基金supported by the National Key Basic Research Program(2013CB956704)
文摘Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increment as well as allometric functions in a karst evergreen and deciduous broadleaved mixed forest in central Guizhou Province, southwestern China. Results showed that the ANPP increased from 1961 to 2015, especially during the last 20–30 years, but with strong variations. The deciduous tree had higher ANPP than the evergreen tree according to two kinds of estimates by the tree ring and girth increment. The averaged ANPP for these two mature trees was 2.27 kg/individual/year, ca. 8 t/ha/year considering the normal stand density. Such karst forest productivity was lower than the natural subtropical forests in China and in the world.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDA05130501)the National Natural Science Foundation of China (Grant Nos. 41471167, 41102114)
文摘According to archaeological investigation and preliminary excavation, the Yangjia Site, located in the northern Taihu Lake region, at Wuxi City, Jiangsu Province, is a Neolithic archaeological site dominated by cultural remains attributed to the late Majiabang Culture(6270–5920 cal. a BP). Here a systematic archaeobotanical study was conducted to investigate vegetation landscape, environmental characteristics and rice agriculture in the prehistoric northern Taihu Lake area. The abundance, frequency and standard density of charred rice were the highest of all of the remains of the seed plants unearthed. In addition, a variety of wetland weeds, such as Haloragaceae, Cyperaceae, Carex sp., and Oxalis corniculata, were found. Pollen and phytoliths recorded that the evergreen-deciduous broadleaf mixed forest(represented by Quercus and Castanopsis) tends to decrease, while Poaceae was the most significant of the terrestrial herbs, water area expanded and water activities strengthened, indicating generally warm and humid conditions at the Yangjia Site during the late Majiabang Culture. All indicators of pollen, phytolith and macro-plant remains suggest that wild rice should be once distributed at or around the site before human occupation, after which rice agriculture progressed rapidly during the late Majiabang Culture.
基金the National Basic Research Program of China(2016YFC0502304,2018YFC0507203,2016YFC0502101)the National Science Foundation of China(31870462)and the Natural Science Foundation of Zhejiang Province(LQ20C030003).
文摘Aims The relationships between plant species and soil microorganisms remain indeterminable in different ecosystems worldwide.In karst ecosystems,soil microbial(SM)community structure and their environmental driving factors are poorly explored,and the relationships between plant species and soil microorganisms are unclear.This study aimed to characterize the general patterns of SM community composition and biomass,and to explore the specific tree species and soil physiochemical properties highly related to SM community diversity and biomass in a karst forest.Methods The effects of tree species on SM community composition and biomass were firstly investigated on the basis of 212 soil samples collected from five dominant tree species(Lithocarpus confinis Huang,Platycarya longipes Wu,Itea yunnanensis Franch.,Machilus cavaleriei H.Lév.and Carpinus pubescens Burkill)through phospholipid fatty acid(PLFA)analysis of a karst evergreen and deciduous broad-leaved mixed forest in central Guizhou Province,southwestern China.The relationships between SM community structure and tree species and soil physiochemical properties were statistically analysed.Important Findings A total of 132 SM-PLFA biomarkers were detected.The average number of SM-PLFA biomarkers and microbial biomass in each soil sample were 65.97 and 11.22µg g^(–1),respectively.Tree species influenced the number of SM-PLFA biomarkers but not the SM biomass.The number of SM-PLFA biomarkers of C.pubescens was significantly higher than that of other species(P<0.05);the numbers of SM-PLFA biomarkers amongst other species showed no significant difference.Microbial biomass showed no relationships with the soil physiochemical properties of nutrient-rich surface soils but positively correlated(P<0.05)with soil organic carbon,nitrogen and phosphorus concentrations in deeper soils.The karst forest in the plateau-surface terrain of central Guizhou Province presented a low fungal-to-bacterial ratio,low microbial biomass storage and high microbial community diversity.Specific tree species affect the SM community diversity in this kind of karst forest.
