扎龙湿地保护区异质生境芦苇种群分株构件的数量特征

Quantitative characteristics of the ramet module of Phragmites australis populations in heterogeneous habitats in the Zhalong Wetland National Reserve

采用单位面积取样,计数和测量的调查与统计方法,对扎龙湿地保护区4个生境单优群落芦苇种群分株构件数量特征进行比较分析。结果表明,4个生境芦苇种群从5月10日左右返青后进入营养生长期,分株高度和分株密度均持续增加到生殖生长初期的8月份,其中6-8月份差异均达到显著水平(P<0.05),8-10月份差异均未达到显著水平(P>0.05),芦苇进入生殖生长期后,分株便停止高度生长,地下芽的输出也不再形成分株补充现实种群;分株生物量和种群生物量均持续增加到生殖生长旺盛期的9月份,至休眠期的10月份均有所降低,各月份间的差异均达到显著水平,芦苇种群在生长季末期,具有将生产的物质分配转移到地下储藏与营养繁殖器官的形成与生长上的特性。芦苇种群分株数量特征与返青后实际生长时间之间均较好地符合对数函数关系,R^2在0.818-0.994之间,拟合方程均达到了P<0.05的显著水平。4个生境芦苇种群分株密度以湿生生境最大,依次为水生生境、旱生生境,盐碱生境最小,分株高度、分株生物量和种群生物量均以水生生境最大,依次为湿生生境、旱生生境,盐碱生境最小。因此,4个生境芦苇种群分株构件数量特征均表现出基本一致的生育期节律性,同时,芦苇种群的个体生长和种群动态存在明显的环境效应,土壤含水量、pH是影响该地区芦苇分株数量特征的主要因子。

By sampling a unit area and using methods such as counting and measuring, a comparative study was performed on the quantitative characteristics of the ramet module of Phragmites australis populations in four habitats in the Zhalong Wetland National Reserve. The results showed that the P. australis populations in the four habitats turned green around May 10 and began to enter the vegetative growth period. The height and density of the ramets continued to increase until the beginning of the reproductive growth period in August, and a significant difference was observed between June and August （P 〈 0.05）. The difference was not significant from August to October （P 〉 0.05）. When the P. australis populations entered the reproductive growth period, the ramets stopped growing in height, and at the same time, the output of the underground bud no longer formed ramets to increase realistic population. The biomass of the ramets and population continued to increase until the beginning of the exuberant reproductive growth period in September, and it decreased when entering the dormant period in October. The difference between each month was significant. At the end of the growing season, P. australis populations showed characteristics such as distributing and transferring the material produced underground for storage as well as contributing to the formation and growth of vegetative reproductive organs. There was a significant logarithmic correlation between the quantitative characteristics of P. australis and the actual growth time after returning green. The goodness of fit of equation was 0.818-0.994, and the fitting equation reached a significant level of P 〈 0.05. The density of ramets was the highest in the wet habitat, followed by the aquatic habitat and xeric habitat; it was the lowest in the saline-alkali habitat. The height and biomass of the ramets and population were the highest in the aquatic habitat, followed by the wet habitat and xeric habitat; it was the lowest in the saline-alkali habitat. Therefore, the quantitative characteristics of the ramets of the P. australis populations in the four habitats showed a basically consistent rhythm in the growth period. Individual growth and population dynamics of the P. australis populations showed obvious environmental effects, and moisture and pH were the main factors that affected the quantitative characteristics of the ramets of the P. australis populations in the Zhalong Wetland National Reserve.