. The biomass dynamics of the pioneer Trema orientalis community in the early stages of secondary succession of tropical forest in Xishuangbanna had been studied for 5 years by the standard tree regression (for trees).... The biomass dynamics of the pioneer Trema orientalis community in the early stages of secondary succession of tropical forest in Xishuangbanna had been studied for 5 years by the standard tree regression (for trees) and clear cut method (for shrub,herb and inter layer plants). 1)The biomass distribution by organs was ranked as stems>branches>roots>leaves. 2)As the succession proceed, the percentages of stem and root biomass increased gradually, the percentage of leaves obviously decreased, and the percentage of branches fluctuated slightly; the dorminant species T. orientalis was replaced gradually by other species,that made the biomass distribution by species appeared to have a characteristics of relative dispersion;the biomass distribution by DBH class showed that biomass was mainly determined by the amounts of larger DBH class trees;the percentage of the tree biomass to the total community biomass gradually increased, the percentages of the shrub and herb layers remarkably decreased and the percentage of the inter-layer plants increased slightly .展开更多
[目的]探讨浓H2SO4浸种处理对狭叶山黄麻种子萌发的影响。[方法]采用浓H2SO4浸种处理,设置1、3、5、7、9、11、13 min 7个浸种时间,研究浓H2SO4处理对狭叶山黄麻种子发芽势和发芽率的影响。[结果]浓H2SO4处理对狭叶山黄麻种子的萌发有...[目的]探讨浓H2SO4浸种处理对狭叶山黄麻种子萌发的影响。[方法]采用浓H2SO4浸种处理,设置1、3、5、7、9、11、13 min 7个浸种时间,研究浓H2SO4处理对狭叶山黄麻种子发芽势和发芽率的影响。[结果]浓H2SO4处理对狭叶山黄麻种子的萌发有极显著的影响,不同处理时间狭叶山黄麻种子发芽率和发芽势有较明显的差异。[结论]在处理时间为9 min时,狭叶黄麻种子发芽势和发芽率均达到最高,分别为45.00%、82.67%。展开更多
文摘. The biomass dynamics of the pioneer Trema orientalis community in the early stages of secondary succession of tropical forest in Xishuangbanna had been studied for 5 years by the standard tree regression (for trees) and clear cut method (for shrub,herb and inter layer plants). 1)The biomass distribution by organs was ranked as stems>branches>roots>leaves. 2)As the succession proceed, the percentages of stem and root biomass increased gradually, the percentage of leaves obviously decreased, and the percentage of branches fluctuated slightly; the dorminant species T. orientalis was replaced gradually by other species,that made the biomass distribution by species appeared to have a characteristics of relative dispersion;the biomass distribution by DBH class showed that biomass was mainly determined by the amounts of larger DBH class trees;the percentage of the tree biomass to the total community biomass gradually increased, the percentages of the shrub and herb layers remarkably decreased and the percentage of the inter-layer plants increased slightly .
文摘[目的]探讨浓H2SO4浸种处理对狭叶山黄麻种子萌发的影响。[方法]采用浓H2SO4浸种处理,设置1、3、5、7、9、11、13 min 7个浸种时间,研究浓H2SO4处理对狭叶山黄麻种子发芽势和发芽率的影响。[结果]浓H2SO4处理对狭叶山黄麻种子的萌发有极显著的影响,不同处理时间狭叶山黄麻种子发芽率和发芽势有较明显的差异。[结论]在处理时间为9 min时,狭叶黄麻种子发芽势和发芽率均达到最高,分别为45.00%、82.67%。