摘要
在合江方竹自然分布区海拔400、600、800、1000和1200 m处分别布设样方,对其退笋规律和影响因素进行了2个年度的研究。结果显示:1)2个年度各海拔处合江方竹的日退笋量均呈"少-多-少"的变化规律,而累计退笋量几乎均呈Logistit曲线增长,中海拔(600 m)退笋总量较大(超过3 000个/667 m^2),而高海拔(1 000和1200 m)的总退笋率较高(超过65%)且进入退笋盛期较早;2)合江方竹的退笋以营养退为主且集中于发笋末期,退笋的易发程度存在年度差异;3)合江方竹发笋10 d左右的高生长速度可能是其退去与否的早期判断依据;4)在无外部干扰的情况下,该竹种的退笋与其发笋量、母竹胸径间存在显著的正相关关系,而与林内最低气温、温度极差间存在显著的负相关关系。研究认为,在合江方竹的经营过程中,在其发笋前及时施肥,并采取适当的覆盖措施保温,可能是降低退笋的有效方法;而在发笋初期根据其高生长速度及时采割利用或清除可能退去的笋,也有利于保证笋产量和竹林的健康发展。
A two-year study was conducted for the mechanism of shoot degradation of Chimonobambusa hejiangensis and influencing factors by sampling at five altitudes（400,600,800,1000 and 1200 m） in one of its natural distribution regions.The results showed：（1） The daily degeneration of Ch.hejiangensis in the two years shoot presented an uptrend and then down trend at different altitudes,while the accumulative shoot degeneration showed an increasing trend resembling Logistic curve.The medium altitude（600 m） was found to have the maximum total shoot degeneration rate（ 3000/667 m^2）,while two relatively higher altitudes（1000 and 1200 m） were found with higher total shoot degeneration rate（65%） and entered the peak of degeneration earlier;（2） The shoot degradation was featured with the degradation of nutrients and mainly occurred at the ending period of shooting,while there were marked differences between two years regarding the degeneration probability;（3） The daily height increment of Ch.hejiangensis shoot about 10 days after shoot emergence might be an early criterion that could be used to distinguish normal and degenerating shoots;（4） Without interference from diseases,pests,human,animals,etc.,the shoot degeneration was positively correlated with shoot emerging amount and diameter of the stock plant,but significantly negatively correlated with the lowest atmosphere temperature and its extreme difference observed in the stand.In practices,fertilization and moderate mulching measures before or/and during the shooting period are recommended to decrease shoot degeneration.Moreover,picking or scavenging degenerating shoots in the initial shooting process might also help much to improve the shoot yield,and thus to promote the sustainable development of bamboo forest.
出处
《世界竹藤通讯》
2016年第1期1-9,共9页
World Bamboo and Rattan
基金
四川省林业厅
四川省财政厅林业科技"先导计划"重点创新研究项目"苦竹
方竹笋用林丰产技术试验"(编号:X04-01)
关键词
合江方竹
退笋动态
分布格局
影响因素
Chimonobambusa hejiangensis
shoot degeneration dynamics
distribution pattern
influence factor
