This research was performed in order to compare the functional traits (morphology, density and biomass) of Phragmites australis (common reed): young vs. old populations which were analyzed along nutrient availability gradient in Lake Burullus (Egypt) every month for a year. The samples were gathered from six sites distributed equally along the northern and southern parts of this lake. The present study indicated that, water N, P, Ca and Mg concentrations of the southern sites were higher than those of the northern sites. Shoot height, stem diameter, number of leaves, flowering ratio, leaf area, and leaf area index (LAI) were significantly lower in young populations compared with old populations. However, shoot density was significantly higher in young populations compared with old populations. The above-ground biomass increased from February until it reached its maximum during August and then decreased again, while a decrease in below-ground biomass in spring to support the rapid shoot growth, followed by an increase in summer due to the shoot translocations in the reverse direction was indicated. The CR (common reed) exhibited a slower relative growth rate (RGR) during cooler months, September–December, while highest RGR was achieved during spring months, March–May. In Lake Burullus the results from this field work indicated that shoot height, stem diameter, number of leaves, flowering ratio, leaf area, LAI, and biomass of CR increased with increasing nutrients along north-south direction in Lake Burullus, where lake eutrophication influenced CR growth positively. Thus, the theory that the biomass and morphology of this macrophyte is determined by the water trophic content is reinforced. The collection of this data is valuable to further comprehend the growth cycle of CR and to contribute to the future management and utilization of CR in the Egyptian wetlands.

进行这项研究是为了比较芦苇的功能性状（形态，密度和生物量）（普通芦苇）：每年对每年在Burullus湖（埃及）中沿营养可利用度梯度进行分析的年轻人和老年人群。样本是从沿该湖北部和南部平均分布的六个地点收集的。目前的研究表明，南部地区的水N，P，Ca和Mg浓度高于北部地区。与老年人群相比，年轻人群的枝条高度，茎直径，叶数，开花率，叶面积和叶面积指数（LAI）显着降低。然而，与老年人群相比，年轻人群的芽密度显着更高。地上生物量从2月开始增加，直到8月达到最大值，然后再次下降，春季春季地下生物量减少以支持新芽的快速生长，夏季则由于相反方向的新芽转移而增加。CR（普通芦苇）在9月至12月的凉爽月份表现出较慢的相对增长率（RGR），而在3月至5月的春季月份则表现出最高的RGR。在Burullus湖中，田间调查的结果表明，随着营养物的增加，沿Burullus湖的南北方向，芽高，茎直径，叶数，开花率，叶面积，LAI和CR的生物量均增加，这对湖泊富营养化产生了影响。 CR增长积极。因此，强化了由水营养含量决定该大型植物的生物量和形态的理论。