中国沙棘平茬萌蘖动态及其对种群结构的影响

Stump sprouting dynamics of Hippophae rhamnoides ssp.sinensis and its effects on population structure

关于中国沙棘平茬萌蘖出生、生长的研究仅有个别报道,且未能将萌蘖特征与种群结构联系起来.该研究在分析中国沙棘平茬萌蘖出生、生长动态的同时,将平茬萌蘖效果与种群稳定性维持联系起来,有助于进一步理解平茬促萌的意义.结果表明:未平茬母株没有萌蘖出生,而平茬处理的萌蘖植株达6.0~25.0;平茬萌蘖植株的树高生长量上限介于28.3~63.0 cm之间,而未平茬母株的新梢生长量上限仅为7.5 cm;未平茬种群结构为稳定型或衰退型,而平茬萌蘖种群结构为增长型.此外,未平茬母株新梢生长只有1次高峰,在6—7月份;平茬萌蘖植株的树高生长有2次高峰,分别在5—6月份、9月份.由此表明,平茬不仅可以促进萌蘖,而且能够加速萌蘖生长、提高种群结构的稳定性.

Researches on the production and growth of stump sprouting of Hippophae rhamnoide ssp.sinensis were infrequently reported, and the relationship between sprout characteristics and population structure was not well documented.To further understand the functions of decapitation for stump sprouting, the spout growing dynamics were analyzed, the effect of the stump sprouting on the population maintenance and stability was studied. No sprouts were found from the mother plants without decapitation （control） , while sprouts ranging from 6.0 to 25.0 were produced from the stumps of decapitated trees （treated）.The maximum growth heights of the cut trees were between 28.3 and 63.0 cm,while the length of new shoot from the intact ones was only 7.5 em.The population structures of the control groups were stationary or senescent, but the treated groups showed incremental pattern. There were one growth peak of shoot height showing in June-July for the control groups and two peaks in May-June and September for the also accelerate the sprout growth cut groups.It is concluded that decapitation can not only promote sprouting, but and stabilize the population structure.