The concentrations of the foliar and surface soil nutrients and the variation with species and stand age were studied inPinus spp. plantations in Zhanggutai area, northeast China. The results showed that the total N, ...The concentrations of the foliar and surface soil nutrients and the variation with species and stand age were studied inPinus spp. plantations in Zhanggutai area, northeast China. The results showed that the total N, total P and C: N ratio of the soil inP. sylvestris var.mongolica stands were significantly higher in comparison with those inP. tabulaeformis andP. densiflora stands. ForP. sylvestris var.mongolica, the foliar P concentration appeared to decrease with age, and the foliar N and K concentrations did not show a consistent change with age. As for the different tree species of the similar age, the foliar N and P concentrations were significantly different (p<0.05), being withP. sylvestris var.mongolica>P. densiflora>P. tabulaeformis. The foliar N: P ratio ofP. densiflora significantly was higher thanP. sylvestris var.mongolica andP. tabulaeformis, while the foliar K was no obvious difference between the three tree species. There were significant correlation (p<0.05) between soil total N and P, soil organic matter and total P, foliar N and P, but it did not show significant correlations between soil and foliar nutrient concentrations, which might attribute to the excessive litter raking, overgrazing and low soil moisture in this area. Based on the foliar N: P ratio, we introduced a combination threshold index of N: P ratio with their absolute foliar nutrient concentrations to determine the possible limiting nutrient. According to the critical N: P ratio and their absolute foliar N, P concentrations, theP. sylvestris var.mongolica stands showed a decreased N limitation degree with age, theP. densiflora stands showed unlimited by N and P in the whole, and theP. tabulaeformis stands showed co-limited by N and P. No significant difference in soil nutrient concentrations of the surface soils was found between 45, 29, 20-yr-oldPinus sylvestris var.mongolica plantation stands. Keywords coniferous trees - foliar nutrient concentration - limiting nutrients - N - P ratio - Zhanggutai sandy land CLC number S718.55 Document code A Article ID 1007-662X(2004)01-0011-08 Foundation item: This research was supported by Key Knowledge Innovation Project (KZCX3-SW-418) of Chinese Academy of Sciences.Biography: CHEN Guang-sheng (1978-), male, master candidate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. ChinaResponsible editor: Song Funan展开更多
The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is ho...The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is household and family. The census is divided by these lines and therefore calculations of household size and complexity are straight forward and this clearly gives one side of the picture. A totally different side is co-residence analysis. This is not straight forward, but because of the standardisation it is doable. By this means, you get a picture of the likelihood that a person of a given age group lives together with specific relatives. It gives an insight into a central part of living conditions and it gives a picture of differences between sexes and urbanisations. The paper brings the two ways of description together and shows that each has something to contribute to the picture of the Danes.展开更多
Leaf morphological and stoichiometric characteristics are considered to represent both the interior inheritable characters in the plant and its adaptations to specific exterior environments. Rhododendron agglutinatum,...Leaf morphological and stoichiometric characteristics are considered to represent both the interior inheritable characters in the plant and its adaptations to specific exterior environments. Rhododendron agglutinatum,an evergreen alpine shrub species,occupies a wide range of habitats above timberline in the Miyaluo Natural Reserve,southwestern China. Along an altitudinal gradient ranging from 3700 to 4150 m,we measured leaf morphological characters including leaf dry matter content(LDMC),leaf dry mass per unit area(LMA),and one leaf area(OLA),as well as carbon(C) and nutrient(N,P) contents in leaves of three different age groups(juvenile leaves,mature leaves and senescent leaves). We also calculated the stoichiometric relationships among carbon and nutrients(C/N,C/P and N/P). Results showed thatboth age and altitude affected the leaf morphological and stoichiometric properties of R. agglutinatum. Mature leaves possessed the highest LDMC,LMA and C contents both on a dry mass basis and on a unit area basis. Younger leaves possessed higher contents of nutrients. OLA as well as ratios between carbon and nutrients(C/N,C/P) increased with ages. Juvenile leaves possessed lowest ratio between nitrogen and phosphorus. In juvenile leaves,nutrients increased with altitudinal elevation,whereas other traits decreased. In mature leaves,nutrients and their ratios with carbon showed consistent trends with juvenile leaves along increasing altitude,whereas LMA and carbon on a unit area basis showed opposite trends with juvenile leaves along increasing altitude. In senescent leaves,only content of phosphorus on a unit area basis and N/P were found linearly correlated with altitude. Our results demonstrated a clear pattern of nutrient distribution with aging process inleaves and indicated that a high possibility of N limitation in this region. We also concluded that younger leaves could be more sensitive to climate changes due to a greater altitudinal influence on the leaf traits in younger leaves than those in elder leaves.展开更多
Five age groups of trees were carried out in order to study relationships between the deterioration of Ponkan mandarin fruit quality and changes in tissues nutrient concentrations with tree age.Fruit quality and nutri...Five age groups of trees were carried out in order to study relationships between the deterioration of Ponkan mandarin fruit quality and changes in tissues nutrient concentrations with tree age.Fruit quality and nutrient concentrations in fruits and leaves were measured.Comprehensive fruit quality decreased in the order:5-year-old > 13-year-old > 38-year-old > 8-year-old >18-year-old.In 18-year-old trees,calcium(Ca) concentrations of fruit and leaf were lower,while potassium(K) and boron(B) concentrations of fruit and magnesium(Mg) and manganese(Mn) concentrations of leaf were higher.Negative relationships were observed between fruit total soluble solids and leaf B,while positive relationships were observed between fruit total soluble solids and leaf and fruit Ca concentrations,and between titratable acidity and leaf Mn.Fruit quality decreasing with tree age most likely resulted from an imbalance of high K,Mg and B but lower Ca concentrations in leaves and fruits.展开更多
A gneissic granite with an U-Pb age of 313±4 Ma was found in northeastern Fujian Province,South China.It is an S-type granite characterized by high K2O,Al2O3 and low SiO2,Na2O contents with high A/CNK ratio of 1....A gneissic granite with an U-Pb age of 313±4 Ma was found in northeastern Fujian Province,South China.It is an S-type granite characterized by high K2O,Al2O3 and low SiO2,Na2O contents with high A/CNK ratio of 1.22 for the whole rock.Zircons with stubby morphology from the gneissic granite yield 206 Pb/238 U ages ranging from 326 to 301 Ma with a weighted average age of 313±4 Ma,and negative εHf(t) values from -8.35 to -1.74 with Hf model ages (TCDM) of 1.43 to 1.84 Ga.This S-type granite probably originated from late Paleoproterozoic crust in intracontinental orogeny.Integrated with previous results on paleogeographic reconstruction of South China,the nature of Paleozoic basins,Early Permian volcanism and U-Pb-Hf isotope of detrital zircons from the late Paleozoic to early Mesozoic sedimentary rocks,we suggest the occurrence of a late Paleozoic orogeny in the eastern Cathaysia Block,South China.This orogenic cycle includes Late Carboniferous (340-310 Ma) orogeny (compression) episode and Early Permian (287-270 Ma) post-orogenic or intraplate extension episode.Therefore,the late Paleozoic magmatism in the southeastern South China probably occurred during the intraplate orogeny rather than the arc-related process.展开更多
Inferior dislocation of the hip is the rarest type in hip dislocation. Very few cases have been reported in the anglophonic literature, most of which involved the pediatric age group. Surprisingly, we came across a 30...Inferior dislocation of the hip is the rarest type in hip dislocation. Very few cases have been reported in the anglophonic literature, most of which involved the pediatric age group. Surprisingly, we came across a 30- year-old patient with a bilateral inferior hip dislocation. He had sustained a road traffic accident and the attitude of both hip joints was flexion and abduction. The diagnosis was confirmed by radiographs which revealed the long axis of the femur at an angle of 1 l0 （right） degrees and 100 （left）degrees respectively away from the axis. Closed reduction under sedation was successfully performed. Skin traction for a period of 6 weeks was advised and the follow-up revealed an excellent result. We present the details of this case, the first of its kind along with a review of the literature, discussing the various modes and mechanisms of injury inducing inferior dislocation of the hip.展开更多
Inferior hip dislocation is the rarest type among all hip dislocations. Very few cases have been re ported in the English literature. Most of the earlier reported cases involves the pediatric age group. No single case...Inferior hip dislocation is the rarest type among all hip dislocations. Very few cases have been re ported in the English literature. Most of the earlier reported cases involves the pediatric age group. No single case series could be found in the English literature. We came across 4 cases of inferior hip dislocation with a varied age profile （range 10 to 56 years, mean 33.8 years）. Patients with this disease usually complained of pain and kept the thigh flexed and abducted. The diagnosis can be confirmed by radiographs which reveal that the long axis of the femur varies in alignment with respect to the spine from parallel toan angle almost 90° away from the axis. In our series, closed reduction was successful in all patients, either under seda tion or general anaesthesia. Skin traction for a period of 6 weeks was applied in all of them and followup revealed painfree, stable and mobile hips. In this study we present the details of these cases along with a review of literature discussing the various modes and mechanisms that pro duce inferior hip dislocation.展开更多
基金Key Knowledge Innovation Project (KZCX3-SW-418) of Chinese Academy of Sciences.
文摘The concentrations of the foliar and surface soil nutrients and the variation with species and stand age were studied inPinus spp. plantations in Zhanggutai area, northeast China. The results showed that the total N, total P and C: N ratio of the soil inP. sylvestris var.mongolica stands were significantly higher in comparison with those inP. tabulaeformis andP. densiflora stands. ForP. sylvestris var.mongolica, the foliar P concentration appeared to decrease with age, and the foliar N and K concentrations did not show a consistent change with age. As for the different tree species of the similar age, the foliar N and P concentrations were significantly different (p<0.05), being withP. sylvestris var.mongolica>P. densiflora>P. tabulaeformis. The foliar N: P ratio ofP. densiflora significantly was higher thanP. sylvestris var.mongolica andP. tabulaeformis, while the foliar K was no obvious difference between the three tree species. There were significant correlation (p<0.05) between soil total N and P, soil organic matter and total P, foliar N and P, but it did not show significant correlations between soil and foliar nutrient concentrations, which might attribute to the excessive litter raking, overgrazing and low soil moisture in this area. Based on the foliar N: P ratio, we introduced a combination threshold index of N: P ratio with their absolute foliar nutrient concentrations to determine the possible limiting nutrient. According to the critical N: P ratio and their absolute foliar N, P concentrations, theP. sylvestris var.mongolica stands showed a decreased N limitation degree with age, theP. densiflora stands showed unlimited by N and P in the whole, and theP. tabulaeformis stands showed co-limited by N and P. No significant difference in soil nutrient concentrations of the surface soils was found between 45, 29, 20-yr-oldPinus sylvestris var.mongolica plantation stands. Keywords coniferous trees - foliar nutrient concentration - limiting nutrients - N - P ratio - Zhanggutai sandy land CLC number S718.55 Document code A Article ID 1007-662X(2004)01-0011-08 Foundation item: This research was supported by Key Knowledge Innovation Project (KZCX3-SW-418) of Chinese Academy of Sciences.Biography: CHEN Guang-sheng (1978-), male, master candidate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. ChinaResponsible editor: Song Funan
文摘The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is household and family. The census is divided by these lines and therefore calculations of household size and complexity are straight forward and this clearly gives one side of the picture. A totally different side is co-residence analysis. This is not straight forward, but because of the standardisation it is doable. By this means, you get a picture of the likelihood that a person of a given age group lives together with specific relatives. It gives an insight into a central part of living conditions and it gives a picture of differences between sexes and urbanisations. The paper brings the two ways of description together and shows that each has something to contribute to the picture of the Danes.
基金supported by the National Natural Science Foundation of China (No.41071039)National Key Research and Development Program (No.2016YFC0502100)
文摘Leaf morphological and stoichiometric characteristics are considered to represent both the interior inheritable characters in the plant and its adaptations to specific exterior environments. Rhododendron agglutinatum,an evergreen alpine shrub species,occupies a wide range of habitats above timberline in the Miyaluo Natural Reserve,southwestern China. Along an altitudinal gradient ranging from 3700 to 4150 m,we measured leaf morphological characters including leaf dry matter content(LDMC),leaf dry mass per unit area(LMA),and one leaf area(OLA),as well as carbon(C) and nutrient(N,P) contents in leaves of three different age groups(juvenile leaves,mature leaves and senescent leaves). We also calculated the stoichiometric relationships among carbon and nutrients(C/N,C/P and N/P). Results showed thatboth age and altitude affected the leaf morphological and stoichiometric properties of R. agglutinatum. Mature leaves possessed the highest LDMC,LMA and C contents both on a dry mass basis and on a unit area basis. Younger leaves possessed higher contents of nutrients. OLA as well as ratios between carbon and nutrients(C/N,C/P) increased with ages. Juvenile leaves possessed lowest ratio between nitrogen and phosphorus. In juvenile leaves,nutrients increased with altitudinal elevation,whereas other traits decreased. In mature leaves,nutrients and their ratios with carbon showed consistent trends with juvenile leaves along increasing altitude,whereas LMA and carbon on a unit area basis showed opposite trends with juvenile leaves along increasing altitude. In senescent leaves,only content of phosphorus on a unit area basis and N/P were found linearly correlated with altitude. Our results demonstrated a clear pattern of nutrient distribution with aging process inleaves and indicated that a high possibility of N limitation in this region. We also concluded that younger leaves could be more sensitive to climate changes due to a greater altitudinal influence on the leaf traits in younger leaves than those in elder leaves.
基金Supported by the Earmarked Fund for the Modern Agro-industry Technology Research System(CARS-27)
文摘Five age groups of trees were carried out in order to study relationships between the deterioration of Ponkan mandarin fruit quality and changes in tissues nutrient concentrations with tree age.Fruit quality and nutrient concentrations in fruits and leaves were measured.Comprehensive fruit quality decreased in the order:5-year-old > 13-year-old > 38-year-old > 8-year-old >18-year-old.In 18-year-old trees,calcium(Ca) concentrations of fruit and leaf were lower,while potassium(K) and boron(B) concentrations of fruit and magnesium(Mg) and manganese(Mn) concentrations of leaf were higher.Negative relationships were observed between fruit total soluble solids and leaf B,while positive relationships were observed between fruit total soluble solids and leaf and fruit Ca concentrations,and between titratable acidity and leaf Mn.Fruit quality decreasing with tree age most likely resulted from an imbalance of high K,Mg and B but lower Ca concentrations in leaves and fruits.
基金supported by the National Basic Research Program of China(2012CB416701)the National Natural Science Foundation of China(40972127)the State Key Laboratory for Mineral Deposits Research(Nanjing University)(ZZKT-201106)
文摘A gneissic granite with an U-Pb age of 313±4 Ma was found in northeastern Fujian Province,South China.It is an S-type granite characterized by high K2O,Al2O3 and low SiO2,Na2O contents with high A/CNK ratio of 1.22 for the whole rock.Zircons with stubby morphology from the gneissic granite yield 206 Pb/238 U ages ranging from 326 to 301 Ma with a weighted average age of 313±4 Ma,and negative εHf(t) values from -8.35 to -1.74 with Hf model ages (TCDM) of 1.43 to 1.84 Ga.This S-type granite probably originated from late Paleoproterozoic crust in intracontinental orogeny.Integrated with previous results on paleogeographic reconstruction of South China,the nature of Paleozoic basins,Early Permian volcanism and U-Pb-Hf isotope of detrital zircons from the late Paleozoic to early Mesozoic sedimentary rocks,we suggest the occurrence of a late Paleozoic orogeny in the eastern Cathaysia Block,South China.This orogenic cycle includes Late Carboniferous (340-310 Ma) orogeny (compression) episode and Early Permian (287-270 Ma) post-orogenic or intraplate extension episode.Therefore,the late Paleozoic magmatism in the southeastern South China probably occurred during the intraplate orogeny rather than the arc-related process.
文摘Inferior dislocation of the hip is the rarest type in hip dislocation. Very few cases have been reported in the anglophonic literature, most of which involved the pediatric age group. Surprisingly, we came across a 30- year-old patient with a bilateral inferior hip dislocation. He had sustained a road traffic accident and the attitude of both hip joints was flexion and abduction. The diagnosis was confirmed by radiographs which revealed the long axis of the femur at an angle of 1 l0 （right） degrees and 100 （left）degrees respectively away from the axis. Closed reduction under sedation was successfully performed. Skin traction for a period of 6 weeks was advised and the follow-up revealed an excellent result. We present the details of this case, the first of its kind along with a review of the literature, discussing the various modes and mechanisms of injury inducing inferior dislocation of the hip.
文摘Inferior hip dislocation is the rarest type among all hip dislocations. Very few cases have been re ported in the English literature. Most of the earlier reported cases involves the pediatric age group. No single case series could be found in the English literature. We came across 4 cases of inferior hip dislocation with a varied age profile （range 10 to 56 years, mean 33.8 years）. Patients with this disease usually complained of pain and kept the thigh flexed and abducted. The diagnosis can be confirmed by radiographs which reveal that the long axis of the femur varies in alignment with respect to the spine from parallel toan angle almost 90° away from the axis. In our series, closed reduction was successful in all patients, either under seda tion or general anaesthesia. Skin traction for a period of 6 weeks was applied in all of them and followup revealed painfree, stable and mobile hips. In this study we present the details of these cases along with a review of literature discussing the various modes and mechanisms that pro duce inferior hip dislocation.
