Population dynamics and growth of Juglans cathayensis seedlings of different slope aspects in the west Tianshan valley in Xinjiang, China
On the basis of the non-destructive determination of seedling age and survey one by one in plots,the static life table of Juglans cathayensis of different slope aspects in the west Tianshan valley in Xinjiang was established,and the quantitative characteristics of seedling height and the growth patterns were analyzed.Results showed that the seedling life expectancy of different slope aspects was longest in the 1st age class,being 2.018 on the sunny slope and 1.766 on the shady slope.The seedling life expectancy was generally higher on the sunny slope than on the shady slope in the 1 st to 6th age classes.The proportions of the seedling population number of different slope aspects were largest in the 1st age class,being 39.7％ on the sunny slope and 44.2％ on the shady slope.The mortality rates of the seedlings were highest in the 3rd age class,with 82.0％ on the sunny slope and 78.3％ on the shady slope.The age structure of the seedling population was of an expanding type,and the survival curve tended to be of Deevey-Ⅱ type regardless of slope aspects.The seedlings could survive only 3.3 ％ on the sunny slope and 1.1％ on the shady slope from 1st to 7th age class.The seedling heights followed an allometry of the exponent function with the age classes,and the growth rate (b value) of the model was substantially the same regardless of slope aspects.
Juglans cathayensisseedlingpopulation dynamicsstatic life tablegrowthslope aspect
国家科技期刊平台
NSTL
万方数据
维普
