Fourteen plots were chosen along with the altitude of 1600-2600 m in Guandi Mountain, Shanxi Province, China to investigate all the trees in the plots, and the species diversity indexes were calculated for analyzing t...Fourteen plots were chosen along with the altitude of 1600-2600 m in Guandi Mountain, Shanxi Province, China to investigate all the trees in the plots, and the species diversity indexes were calculated for analyzing the effects of altitudinal gradient on plant species diversity. The results showed that the order of dominant species from low altitude to high altitude is as Quercus liaotungensis Koidz, Pinus tabulaeformis, Betula platyphylla, B. albo-sinensis, Picea wilsonii, P. Meyeri and Larix principis-rupprechtii. With altitude increasing, the average height and DBH of the arbor firstly increase and then decrease, the maximal height and DBH of the arbor present the unimodal variable trend, the maximal height of coniferous and broad-leaved trees firstly increases and then decreases, the maximal DBH of broad-leaf trees has no clear fluctuation, and the maximal DBH of the needle-leaf trees decreases gradually. Moreover, in middle altitudinal communities (the altitude of 1900-2200 m), the maximal height and DBH of the needle-leaf trees are larger than these of broad-leaf trees. Both Shannon-wiener index and Margalef index of the communities present the unimodal variable trend, with a peak in the mid-altitude. Plant species diversity in the mid-altitude (1900-2200 m) is higher than that of the low altitude (1600-1900 m) and the high altitude (2200-2600 m). In addition, the unimodal variable trend of α species diversity is clearly correlated with the altitudinal gradient. The change of plant species diversity is significantly correlated with the altitudinal gradient, and also related to the community structure, the community composition, the feature of species and the human disturbance.展开更多
By the method of gradient pattern analysis, twenty plots were set at altitudes of 700-2600 m with an interval of 100 m on the northern slope of the Changbai Mountain. The dissimilarity of respective sub-plots in the s...By the method of gradient pattern analysis, twenty plots were set at altitudes of 700-2600 m with an interval of 100 m on the northern slope of the Changbai Mountain. The dissimilarity of respective sub-plots in the same community was measured and the complexity of plant communities at different altitudes was analyzed. The result from binary data of tree species in canopy tree indicated that the sub-plots in the communities, except subalpine Betula ermanii forest, showed comparatively high dissimilarity in species composition. Especially, the dissimilarity index (0.7) of broadleaved/Korean pine forest at low altitudes was obviously higher than other communities. The differences are not obvious between communities referring to dark coniferous forest. Comparatively, the dissimilarity in sub-plots of the communities at altitude of 1400 m was slightly higher than that of other communities, which reflected the complexity of tree species compositions of transitory-type communities. For subalpine Betula ermanii forest, tree species composition was simple and showed a high similarity between sub-plots. The results derived from binary data of shrub showed that the dissimilarity index of shrub species in broadleaved/Korean pine forest at low altitudes was higher than that in other communities, but the divergence tendency wasn抰 so obvious as that of arbor species. The dissimilarity derived from binary data of herb and all plant species at different altitudes showed greatly close tendency, and the differences in herb and all plant species between sub-plots were the greatest for the communities of broad-leaved-Korean pine forest and alpine tundra zone..展开更多
Twenty plots were investigated on northern slope of Changbai Mountain at an attitude interval of 100 m (from 700 to 2600 m). The species co-possession between plant communities at different altitudes was analyzed by J...Twenty plots were investigated on northern slope of Changbai Mountain at an attitude interval of 100 m (from 700 to 2600 m). The species co-possession between plant communities at different altitudes was analyzed by Jaccard index. The analytical results showed that the co-possession calculated according to species in different layers or all species between adjacent communities was higher than that between disjunct communities. The co-possessions between adjacent communities calculated by species in different layers had comparability and dissimilarity. If the two adjacent communities belong to different types of vegetation, then their co-possession was lower. The peak values and valley values of species co-possession between communities along elevation gradient just matched vegetation gradient patterns, and species subrogation of shrubs had more obvious rule on northern slope of Changbai Mountain. Co-possessions between communities with same altitude difference were much similar, and it decreased as the increase of elevation difference, which showed that species compositions in different layers of the communities were highly related.展开更多
River discharge can deliver nutrients to the coastal zone and change the hydrologic properties of the water column. Soon after a flash flood from the Yalu River (Northeast China) in August 2010, we investigated the sa...River discharge can deliver nutrients to the coastal zone and change the hydrologic properties of the water column. Soon after a flash flood from the Yalu River (Northeast China) in August 2010, we investigated the salinity and nutrient concentrations, as well as other environmental conditions in the Changshan Archipelago area, located approximately 100 km west of the river mouth in the northern Yellow Sea. Diluted water was mainly observed in the upper layers shallower than 15 m, with surface salinity between 18.13 and 30.44 in the eastern study area and between 28.16 and 29.72 in the western area. Surface salinity showed a significant negative correlation with concentrations of dissolved nutrients (P < 0.05), but not with that of Chlorophyll-a (Chl-a), dissolved oxygen (DO), particulate materials or pH. The average concentrations of nitrite, nitrate, and silicic acid decreased from the surface layer to bottom layer and were significantly higher in the east area than in the west area (P < 0.05). In contrast, average ammonium and phosphate concentrations were highest in the bottom layer of both areas, with no significant spatial differences. DO varied between 6.06 and 8.25 mg L-1 in the surface layer, and was significantly higher in the eastern area than in the western area in the surface and middle layers. Chl-a concentration was constantly below 4.09 μg L-1. Our work demonstrated the strong influences of Yalu River on proportions of various nutrient components in the Changshan Archipelago area. Silicic acid and total inorganic nitrogen levels were significantly elevated comparing to phosphate in the eastern area. Such changes can potentially induce phosphate limit to phytoplankton growth.展开更多
Changes in permanent sample plots in the lowland,submontane and montane forests on Mount Cameroon(4,095 m above sea level),an active volcano,are described for 15 years from 1989 to 2004.Throughout the study period,the...Changes in permanent sample plots in the lowland,submontane and montane forests on Mount Cameroon(4,095 m above sea level),an active volcano,are described for 15 years from 1989 to 2004.Throughout the study period,the stocking level of trees with a diameter at breast height(DBH) ≥ 10 cm in the three forests were lower than in pan-tropical stands suggesting a significant impact of volcanic and human-related activities on the vegetation communities on the mountain.Annual mortality rates in the submontane and montane forests were consistent with those reported for comparable altitudinal ranges in the Blue Mountains of Jamaica.The annual mortality rate was higher in the lowland forest than other lowland sites included.Divergence between recruitment and mortality rates was large suggesting that the three vegetation communities have not reached their climax.The seven-year difference in half-life of large trees(with a DBH ≥ 50 cm) in the submontane and montane forests suggests an altitudinal effect on turnover of larger trees that in turn contributes to the frequent small stature of high altitude forests.There was little evidence of an altitudinal effect on species turnover and growth rate.This finding supports generalizations about the zero effect of growth on the stature of high altitude trees.Understanding forest dynamics is crucially important in the management of tropical montane environmentsand in this instance particularly so given the recent creation of the Mount Cameroon National Park.展开更多
This study analyzes six vegetation communities in relation to current climatic parameters and eight climate change scenarios along an elevation gradient extending from 2,710 m to 4,210 m in the Trans-Mexican Volcanic ...This study analyzes six vegetation communities in relation to current climatic parameters and eight climate change scenarios along an elevation gradient extending from 2,710 m to 4,210 m in the Trans-Mexican Volcanic Belt. The projected movements of 25 plant species with the current restricted or wide altitudinal distributions were also modeled. To relate climatic parameters to the species and communities, a Precipitation/Temperature (P/T) index was used both for the current and the different climate-change scenarios. The temperatures are expected to increase by 1.1℃ to 1.7℃ by 2020 and by 2℃ to 3℃ by 2o5o. A decrease of 4% to 13% in the annual precipitation is expected for the 2020 horizon, and a reduction between 3% and 20% is expected for 2050. The reductions in water availability were projected for all altitude levels and plant communities. The most marked reduction was under the HADLEY- A2 scenario, in which the lower limit of the altitudinal range increased from 2,71o to 3,31o m (2050 horizon) with reductions in the P/T index between 36% and 39% compared to the current climate. Most plant species tended to shift their distribution from 20o to 300 m upward in the 2020 temporal horizon scenarios. The Pinus hartwegii, Alnus jorullensis and Pinus montezumae communities would have a shorter altitudinal range as they move upward and merge with the remaining species at the higher altitudinal range. For the 2o5o temporal horizon, 3o% of the species, primarily those from the higher altitudinal range, would disappear because their P/Tindex values would be above the limit of plant survival (〉4,210 m).展开更多
On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first time.The Devonian rocks include the Middle Devonian ...On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first time.The Devonian rocks include the Middle Devonian Jinbo Formation and the Upper Devonian Changjiang Formation,which are distributed in northwestern Hainan Island.The Jinbo Formation is represented by631 m of littoral facies deposits,and was intruded by the Yanshanian granite in the base.The presence of chitinozoans Eisenackitina caster,Funsochitina pilosa,and Lagenochitina amottensis indicates the Givetian in age.The Changjiang Formation is made up of 140 m of neritic facies rocks,and contains the Famennian conodonts Palmatolepis gracilis sigmoidalis,Polygnathus germanus,and corals Cystophrentis kalaohoensis.The Devonian-Tournaisian transition beds,the lower part of the Jishi Formation,are composed of 61–129 m sandstone and siltstone,with gastropods Euomphalus spp.and brachiopods,and marked by conglomerate with the underlying Devonian rocks.The middle-upper part of the Tournaisian Jishi Formation consists of 100–251 m clastic and carbonate rocks,containing abundant corals Pseudoularinia irregularis,conodonts Siphonodella isosticha,trilobites Weberiphillipsia linguiformis,and brachiopods.On the basis of the occurrence of Xinanosprifer flabellum and Homotoma sp.,the Nanhao Formation in southern Hainan Island is now regarded as the Lower Silurian,instead of the previously designated Lower Carboniferous.It is confirmed that no Carboniferous rocks occurred in the area south to the Gancheng-Wanning Fault.展开更多
The Changbai Mountains, located in northeastern China, show clear vertical zonation of vegetation types. Six different habitats,namely Pinus koraiensis mixed broad-leaved forest, Pinus koraiensis-Picea forest, spruce-...The Changbai Mountains, located in northeastern China, show clear vertical zonation of vegetation types. Six different habitats,namely Pinus koraiensis mixed broad-leaved forest, Pinus koraiensis-Picea forest, spruce-fir forest, Betula ermanii forest, alpine meadow and alpine semi-desert, at elevations ranging from 780 to 2 480 m, covering almost all ecosystems on the north slope of the Changbai Mountains, were investigated to determine: i) whether or not the community composition of soil mesofauna varied significantly at different elevations; ii) if different soil mesofauna groups would respond differently to elevation and iii) which factors influenced the spatial distribution of soil mesofauna along elevation. Soil mesofauna were collected from each habitat in spring(May),summer(July) and autumn(September) of 2009. The soil mesofauna communities were comprised of at least 44 groups and were dominated by Acari and Collembola, followed by Coleoptera, Diptera larvae and Enchytraeidae. The composition, diversity and abundance of soil mesofauna varied among the six habitats. Meanwhile, significant seasonal variations were observed in the composition,abundance and diversity of the soil mesofauna in each habitat. The taxonomic richness and Shannon index were affected by elevation and soil properties, while the abundance was only significantly affected by soil properties. With regard to taxa, the habitats and seasons had significant effects on almost all the abundances of the major taxonomic groups. The abundance of more taxonomic groups was significantly influenced by the soil properties, while those of Geophilomorpha, Araneae and other taxa were affected by elevation.It is concluded that the composition and spatial distribution of the soil mesofauna varied along the elevation gradient on the north slope of the Changbai Mountains, which might be largely related to the variations of the plant community, soil properties and climate change resulting from the elevation gradient.展开更多
基金This paper was supported by Shanxi Natural Science Foun-dation (20001090)
文摘Fourteen plots were chosen along with the altitude of 1600-2600 m in Guandi Mountain, Shanxi Province, China to investigate all the trees in the plots, and the species diversity indexes were calculated for analyzing the effects of altitudinal gradient on plant species diversity. The results showed that the order of dominant species from low altitude to high altitude is as Quercus liaotungensis Koidz, Pinus tabulaeformis, Betula platyphylla, B. albo-sinensis, Picea wilsonii, P. Meyeri and Larix principis-rupprechtii. With altitude increasing, the average height and DBH of the arbor firstly increase and then decrease, the maximal height and DBH of the arbor present the unimodal variable trend, the maximal height of coniferous and broad-leaved trees firstly increases and then decreases, the maximal DBH of broad-leaf trees has no clear fluctuation, and the maximal DBH of the needle-leaf trees decreases gradually. Moreover, in middle altitudinal communities (the altitude of 1900-2200 m), the maximal height and DBH of the needle-leaf trees are larger than these of broad-leaf trees. Both Shannon-wiener index and Margalef index of the communities present the unimodal variable trend, with a peak in the mid-altitude. Plant species diversity in the mid-altitude (1900-2200 m) is higher than that of the low altitude (1600-1900 m) and the high altitude (2200-2600 m). In addition, the unimodal variable trend of α species diversity is clearly correlated with the altitudinal gradient. The change of plant species diversity is significantly correlated with the altitudinal gradient, and also related to the community structure, the community composition, the feature of species and the human disturbance.
基金supported by the Chinese Academy of Science(grand KZCX2-406)founded by Chinese Science of Academy undred People’Project.
文摘By the method of gradient pattern analysis, twenty plots were set at altitudes of 700-2600 m with an interval of 100 m on the northern slope of the Changbai Mountain. The dissimilarity of respective sub-plots in the same community was measured and the complexity of plant communities at different altitudes was analyzed. The result from binary data of tree species in canopy tree indicated that the sub-plots in the communities, except subalpine Betula ermanii forest, showed comparatively high dissimilarity in species composition. Especially, the dissimilarity index (0.7) of broadleaved/Korean pine forest at low altitudes was obviously higher than other communities. The differences are not obvious between communities referring to dark coniferous forest. Comparatively, the dissimilarity in sub-plots of the communities at altitude of 1400 m was slightly higher than that of other communities, which reflected the complexity of tree species compositions of transitory-type communities. For subalpine Betula ermanii forest, tree species composition was simple and showed a high similarity between sub-plots. The results derived from binary data of shrub showed that the dissimilarity index of shrub species in broadleaved/Korean pine forest at low altitudes was higher than that in other communities, but the divergence tendency wasn抰 so obvious as that of arbor species. The dissimilarity derived from binary data of herb and all plant species at different altitudes showed greatly close tendency, and the differences in herb and all plant species between sub-plots were the greatest for the communities of broad-leaved-Korean pine forest and alpine tundra zone..
基金the Chinese Academy of Science (a grant KZCX2-406), National Natural Science Foundation of China (NSFC39970123), and Changbai Mo
文摘Twenty plots were investigated on northern slope of Changbai Mountain at an attitude interval of 100 m (from 700 to 2600 m). The species co-possession between plant communities at different altitudes was analyzed by Jaccard index. The analytical results showed that the co-possession calculated according to species in different layers or all species between adjacent communities was higher than that between disjunct communities. The co-possessions between adjacent communities calculated by species in different layers had comparability and dissimilarity. If the two adjacent communities belong to different types of vegetation, then their co-possession was lower. The peak values and valley values of species co-possession between communities along elevation gradient just matched vegetation gradient patterns, and species subrogation of shrubs had more obvious rule on northern slope of Changbai Mountain. Co-possessions between communities with same altitude difference were much similar, and it decreased as the increase of elevation difference, which showed that species compositions in different layers of the communities were highly related.
基金supported by the Knowledge Innovation Program of Chinese Academy of Sciences,the IOCAS-Zhangzidao Fishery Eco-Mariculture Joint Laboratorythe National Key Technology Research and Development Program (2008BAC42B01)
文摘River discharge can deliver nutrients to the coastal zone and change the hydrologic properties of the water column. Soon after a flash flood from the Yalu River (Northeast China) in August 2010, we investigated the salinity and nutrient concentrations, as well as other environmental conditions in the Changshan Archipelago area, located approximately 100 km west of the river mouth in the northern Yellow Sea. Diluted water was mainly observed in the upper layers shallower than 15 m, with surface salinity between 18.13 and 30.44 in the eastern study area and between 28.16 and 29.72 in the western area. Surface salinity showed a significant negative correlation with concentrations of dissolved nutrients (P < 0.05), but not with that of Chlorophyll-a (Chl-a), dissolved oxygen (DO), particulate materials or pH. The average concentrations of nitrite, nitrate, and silicic acid decreased from the surface layer to bottom layer and were significantly higher in the east area than in the west area (P < 0.05). In contrast, average ammonium and phosphate concentrations were highest in the bottom layer of both areas, with no significant spatial differences. DO varied between 6.06 and 8.25 mg L-1 in the surface layer, and was significantly higher in the eastern area than in the western area in the surface and middle layers. Chl-a concentration was constantly below 4.09 μg L-1. Our work demonstrated the strong influences of Yalu River on proportions of various nutrient components in the Changshan Archipelago area. Silicic acid and total inorganic nitrogen levels were significantly elevated comparing to phosphate in the eastern area. Such changes can potentially induce phosphate limit to phytoplankton growth.
文摘Changes in permanent sample plots in the lowland,submontane and montane forests on Mount Cameroon(4,095 m above sea level),an active volcano,are described for 15 years from 1989 to 2004.Throughout the study period,the stocking level of trees with a diameter at breast height(DBH) ≥ 10 cm in the three forests were lower than in pan-tropical stands suggesting a significant impact of volcanic and human-related activities on the vegetation communities on the mountain.Annual mortality rates in the submontane and montane forests were consistent with those reported for comparable altitudinal ranges in the Blue Mountains of Jamaica.The annual mortality rate was higher in the lowland forest than other lowland sites included.Divergence between recruitment and mortality rates was large suggesting that the three vegetation communities have not reached their climax.The seven-year difference in half-life of large trees(with a DBH ≥ 50 cm) in the submontane and montane forests suggests an altitudinal effect on turnover of larger trees that in turn contributes to the frequent small stature of high altitude forests.There was little evidence of an altitudinal effect on species turnover and growth rate.This finding supports generalizations about the zero effect of growth on the stature of high altitude trees.Understanding forest dynamics is crucially important in the management of tropical montane environmentsand in this instance particularly so given the recent creation of the Mount Cameroon National Park.
文摘This study analyzes six vegetation communities in relation to current climatic parameters and eight climate change scenarios along an elevation gradient extending from 2,710 m to 4,210 m in the Trans-Mexican Volcanic Belt. The projected movements of 25 plant species with the current restricted or wide altitudinal distributions were also modeled. To relate climatic parameters to the species and communities, a Precipitation/Temperature (P/T) index was used both for the current and the different climate-change scenarios. The temperatures are expected to increase by 1.1℃ to 1.7℃ by 2020 and by 2℃ to 3℃ by 2o5o. A decrease of 4% to 13% in the annual precipitation is expected for the 2020 horizon, and a reduction between 3% and 20% is expected for 2050. The reductions in water availability were projected for all altitude levels and plant communities. The most marked reduction was under the HADLEY- A2 scenario, in which the lower limit of the altitudinal range increased from 2,71o to 3,31o m (2050 horizon) with reductions in the P/T index between 36% and 39% compared to the current climate. Most plant species tended to shift their distribution from 20o to 300 m upward in the 2020 temporal horizon scenarios. The Pinus hartwegii, Alnus jorullensis and Pinus montezumae communities would have a shorter altitudinal range as they move upward and merge with the remaining species at the higher altitudinal range. For the 2o5o temporal horizon, 3o% of the species, primarily those from the higher altitudinal range, would disappear because their P/Tindex values would be above the limit of plant survival (〉4,210 m).
基金supported by National Natural Science Foundation of China(Grant Nos.40772022,41172025)China Geological Survey Project(Grant Nos.1212011120116,1212011220517)
文摘On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first time.The Devonian rocks include the Middle Devonian Jinbo Formation and the Upper Devonian Changjiang Formation,which are distributed in northwestern Hainan Island.The Jinbo Formation is represented by631 m of littoral facies deposits,and was intruded by the Yanshanian granite in the base.The presence of chitinozoans Eisenackitina caster,Funsochitina pilosa,and Lagenochitina amottensis indicates the Givetian in age.The Changjiang Formation is made up of 140 m of neritic facies rocks,and contains the Famennian conodonts Palmatolepis gracilis sigmoidalis,Polygnathus germanus,and corals Cystophrentis kalaohoensis.The Devonian-Tournaisian transition beds,the lower part of the Jishi Formation,are composed of 61–129 m sandstone and siltstone,with gastropods Euomphalus spp.and brachiopods,and marked by conglomerate with the underlying Devonian rocks.The middle-upper part of the Tournaisian Jishi Formation consists of 100–251 m clastic and carbonate rocks,containing abundant corals Pseudoularinia irregularis,conodonts Siphonodella isosticha,trilobites Weberiphillipsia linguiformis,and brachiopods.On the basis of the occurrence of Xinanosprifer flabellum and Homotoma sp.,the Nanhao Formation in southern Hainan Island is now regarded as the Lower Silurian,instead of the previously designated Lower Carboniferous.It is confirmed that no Carboniferous rocks occurred in the area south to the Gancheng-Wanning Fault.
基金supported by the National Natural Science Foundation of China (Nos. 41471211 and 41171207)
文摘The Changbai Mountains, located in northeastern China, show clear vertical zonation of vegetation types. Six different habitats,namely Pinus koraiensis mixed broad-leaved forest, Pinus koraiensis-Picea forest, spruce-fir forest, Betula ermanii forest, alpine meadow and alpine semi-desert, at elevations ranging from 780 to 2 480 m, covering almost all ecosystems on the north slope of the Changbai Mountains, were investigated to determine: i) whether or not the community composition of soil mesofauna varied significantly at different elevations; ii) if different soil mesofauna groups would respond differently to elevation and iii) which factors influenced the spatial distribution of soil mesofauna along elevation. Soil mesofauna were collected from each habitat in spring(May),summer(July) and autumn(September) of 2009. The soil mesofauna communities were comprised of at least 44 groups and were dominated by Acari and Collembola, followed by Coleoptera, Diptera larvae and Enchytraeidae. The composition, diversity and abundance of soil mesofauna varied among the six habitats. Meanwhile, significant seasonal variations were observed in the composition,abundance and diversity of the soil mesofauna in each habitat. The taxonomic richness and Shannon index were affected by elevation and soil properties, while the abundance was only significantly affected by soil properties. With regard to taxa, the habitats and seasons had significant effects on almost all the abundances of the major taxonomic groups. The abundance of more taxonomic groups was significantly influenced by the soil properties, while those of Geophilomorpha, Araneae and other taxa were affected by elevation.It is concluded that the composition and spatial distribution of the soil mesofauna varied along the elevation gradient on the north slope of the Changbai Mountains, which might be largely related to the variations of the plant community, soil properties and climate change resulting from the elevation gradient.