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
Quantitative dynamics and viability of a rare and wild Cycas fairylakea population were studied with a time-specific life table, a Leslie matrix model and a survival function in order to provide scientific guidance fo...Quantitative dynamics and viability of a rare and wild Cycas fairylakea population were studied with a time-specific life table, a Leslie matrix model and a survival function in order to provide scientific guidance for its protection. The results of the time- specific life table show that this C. fairylakea population suffered a high death rate in three age classes, i.e., age class 1 (0-15 years), V (61-75 years) and VI (76-90 years). The Leslie matrix model suggests that the number of plants would decline from the present 1613 to 59 per hectare in 150 years. Furthermore, the viability analysis indicates that seedlings have the highest mortality density rate and that middle-aged plants (i.e., 61-75 years, 76-90 years) have high mortality density rate and hazard rate. These conditions affect natural regeneration of the population and lead to a lack of seedlings which in turn causes the extinction of the population. An in situ conservation of the population should be established and protection measures taken as soon as possible.展开更多
A new Vary in Distance Leslie Matrix is adopted to process the observed data of a giant panda population’s development trend dynamics with unequal distance age groups. Results show that this new method adopted is mu...A new Vary in Distance Leslie Matrix is adopted to process the observed data of a giant panda population’s development trend dynamics with unequal distance age groups. Results show that this new method adopted is much simpler than the usual lesile Matrix analysis, and no need of deviding the pandas into equal distance age groups and no so many asumptions are needed as in the usual Leslie Methods. We only changed the meaning of some elements in Leslie Matrix and processed the developmental trend of panda population in Wolong Wu Yi Peng successfully we also carried out a sensitivity analysis of many parameters as well as the computer simulation.展开更多
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Quantitative dynamics and viability of a rare and wild Cycas fairylakea population were studied with a time-specific life table, a Leslie matrix model and a survival function in order to provide scientific guidance for its protection. The results of the time- specific life table show that this C. fairylakea population suffered a high death rate in three age classes, i.e., age class 1 (0-15 years), V (61-75 years) and VI (76-90 years). The Leslie matrix model suggests that the number of plants would decline from the present 1613 to 59 per hectare in 150 years. Furthermore, the viability analysis indicates that seedlings have the highest mortality density rate and that middle-aged plants (i.e., 61-75 years, 76-90 years) have high mortality density rate and hazard rate. These conditions affect natural regeneration of the population and lead to a lack of seedlings which in turn causes the extinction of the population. An in situ conservation of the population should be established and protection measures taken as soon as possible.
文摘A new Vary in Distance Leslie Matrix is adopted to process the observed data of a giant panda population’s development trend dynamics with unequal distance age groups. Results show that this new method adopted is much simpler than the usual lesile Matrix analysis, and no need of deviding the pandas into equal distance age groups and no so many asumptions are needed as in the usual Leslie Methods. We only changed the meaning of some elements in Leslie Matrix and processed the developmental trend of panda population in Wolong Wu Yi Peng successfully we also carried out a sensitivity analysis of many parameters as well as the computer simulation.