4种浮床栽培植物生长特性及吸收氮磷能力的比较

Comparison of the growth characteristics and nutrient uptake of four kinds of plants cultivated on a floating-bed

选取美人蕉、风车草、菖蒲和香根草4种常见的浮床植物为研究对象,对其生长特性及吸收氮磷的能力进行比较研究.结果显示,4种植物的成活率均在90%以上,移栽后60 ～100d为植物的快速生长期.经过4个月的生长,4种植物水面上部生物量均明显高于下部;除香根草外,其它3种植物体内的氮磷含量均呈叶>根>茎的分布;植物体内的氮、磷累积量大小依次为美人蕉>风车草>菖蒲>香根草.植物吸收占浮床系统氮去除的比例均低于40%,占浮床系统磷去除的比例均高于55%.4种植物中,美人蕉对水体中氮磷的吸收能力最强,可以将其作为三峡库区次级河流的浮床栽培植物进行推广.

Taking Canna indica, Cyperus alternifolius, Acorus calamus Linn and Vetiveria zizanioiaes as research subjects, the characteristics and nutrient uptake abilities of these four familiar plants cultivated on a floating-bed were compared. The survival rates of the four plants were more than 90%. The rapid growth period was from sixty days to one hundred days after planting. After four months, the above-water biomass of the four kinds of plants was greater than the underwater biomass. Except for Vetiver zizanioides, the distributions of nitrogen and phosphorus in the plants could be summarized as follows： leaves 〉 roots 〉 stems. The total quantities of nitrogen and phosphorus in the plants were in the following order： Canna indica 〉 Cyperus alternifolius 〉 Acorus calamus Linn 〉 Vetiveria zizanioiaes. Nitrogen uptake by the plants accounted for less than 40% of the floating-bed system nitrogen removal, and the phosphorus uptake was more than 55%. Canna indica has the strongest uptake ability for nitrogen and phosphorus. A Canna indica floating-bed could therefore be used to control pollution in the Three Gorges reservoir region.