Comparing with an affinity and widespread species Adenophora potaninii the age structures of A. loboPhylla population, an endangered plant species were studied. 29 sample plots were investigated in the centered distri...Comparing with an affinity and widespread species Adenophora potaninii the age structures of A. loboPhylla population, an endangered plant species were studied. 29 sample plots were investigated in the centered distribution area, Jinchuan county from altitude 2 300 m to 3 400 m. The main factors which influence the population age structures of A. lobophylla were analyzed. The principal characteristics of A. lobophylla populations are that the number of seedling and the density of population are much less than these of A. potaninii population. Below aititude of 2 700 m, the age structures of most A. lobophylla populations show the declining status, only above altitude of 2 700 m they are stable, while age structures of all populations of A. potaninll populations at corresponding altitude perform stable and developing features. The age structure patterns, relations between age (X) and number of individual (y) of stable populations of A. lobophylla can be expressed by equation : y =e(a-bx), and the longest life spah is 25a. Whereas A. potaninii populations can be expressed by the equationf y =ax-b, and the longest life span of individual is 21a. The external factors, which constrain the extension of A. lobophylla population, are extreme environmental conditions such as serious drought, external disturbance and low temperature.展开更多
The population dynamic tendency of Adenophora Iobophvlla Hong as an endangered species and Adenophora potaninii Korsh as widespread species. has been predicted by the Leslie matrix. And the comparison and analysis on ...The population dynamic tendency of Adenophora Iobophvlla Hong as an endangered species and Adenophora potaninii Korsh as widespread species. has been predicted by the Leslie matrix. And the comparison and analysis on the age structures between two species have been carried out in this paper. The results demonstrate the A. lobophylla popuations which have the reasonable age struetures perform slowly negative or positive increment at altitude 2300-3400 m. Especially. below altitude 2700 m. there are many populations performing seriously declining tendcncy. Contrary, A potaninii populations could adapt to environment perfectly at the corresponding condition without finding the population which performs the seriously declining tendency. The differences in developing tendency of population between the two species demonstrate that A. Iobopliylla populations have the weaker ability to adapt to the external unfavorable conditions.展开更多
The photosynthesis and transpiration characteristics of Adenophora lobophylla and A. potaninii as well as stomatal behavior such as stomatal size, stomatal density, stomatal open and stomatal conductivity were measure...The photosynthesis and transpiration characteristics of Adenophora lobophylla and A. potaninii as well as stomatal behavior such as stomatal size, stomatal density, stomatal open and stomatal conductivity were measured at different altitudes. The relationship between the photosynthesis and transpiration characteristics and the stomatal behavior was analysed by correlation coefficient and path coefficient analysis with altitude changes.The results showed that the inffuences of stomatal behavior were not evident on the photosynthesis and transpiration characteristics of A. Lobophylla, but evident on that of A. potaninii.展开更多
文摘Comparing with an affinity and widespread species Adenophora potaninii the age structures of A. loboPhylla population, an endangered plant species were studied. 29 sample plots were investigated in the centered distribution area, Jinchuan county from altitude 2 300 m to 3 400 m. The main factors which influence the population age structures of A. lobophylla were analyzed. The principal characteristics of A. lobophylla populations are that the number of seedling and the density of population are much less than these of A. potaninii population. Below aititude of 2 700 m, the age structures of most A. lobophylla populations show the declining status, only above altitude of 2 700 m they are stable, while age structures of all populations of A. potaninll populations at corresponding altitude perform stable and developing features. The age structure patterns, relations between age (X) and number of individual (y) of stable populations of A. lobophylla can be expressed by equation : y =e(a-bx), and the longest life spah is 25a. Whereas A. potaninii populations can be expressed by the equationf y =ax-b, and the longest life span of individual is 21a. The external factors, which constrain the extension of A. lobophylla population, are extreme environmental conditions such as serious drought, external disturbance and low temperature.
文摘The population dynamic tendency of Adenophora Iobophvlla Hong as an endangered species and Adenophora potaninii Korsh as widespread species. has been predicted by the Leslie matrix. And the comparison and analysis on the age structures between two species have been carried out in this paper. The results demonstrate the A. lobophylla popuations which have the reasonable age struetures perform slowly negative or positive increment at altitude 2300-3400 m. Especially. below altitude 2700 m. there are many populations performing seriously declining tendcncy. Contrary, A potaninii populations could adapt to environment perfectly at the corresponding condition without finding the population which performs the seriously declining tendency. The differences in developing tendency of population between the two species demonstrate that A. Iobopliylla populations have the weaker ability to adapt to the external unfavorable conditions.
文摘The photosynthesis and transpiration characteristics of Adenophora lobophylla and A. potaninii as well as stomatal behavior such as stomatal size, stomatal density, stomatal open and stomatal conductivity were measured at different altitudes. The relationship between the photosynthesis and transpiration characteristics and the stomatal behavior was analysed by correlation coefficient and path coefficient analysis with altitude changes.The results showed that the inffuences of stomatal behavior were not evident on the photosynthesis and transpiration characteristics of A. Lobophylla, but evident on that of A. potaninii.
