高效吸收氮、磷的滨岸缓冲带植物筛选

Screening of Plants with Efficient Absorption of Nitrogen and Phosphorus for Riparian Buffer Zones

为建立有效的滨岸缓冲带水体工程,选择了草木犀(Melilotus suaveolens Ledeb.)、白三叶(Trifolium repensL.)、野薄荷(Menthasa chalinensis(Briq.)Kudo)、马唐(Digitaria sanguinalis(L.)Scop)、夏枯草(Prunellaasi-aticaNikai)5种经济植物,并研究了其生物学特性及其对氮、磷营养元素的净化能力。结果表明:每种植物的根长、茎长和分叶都有不同程度的增长,同时每种经济植物对水体中氨氮和可溶性磷酸盐均有一定的吸收作用。在较低的氮、磷水平条件下,草木犀、白三叶分别对氨氮和可溶性磷酸盐的吸收效果最好,吸收率分别达到75.69%、83.70%。夏枯草在中等和较高的氮、磷水平条件下对氨氮的吸收效果最好,吸收率分别达到73.76%、71.85%,对可溶性磷酸盐的吸收效果也最好,吸收率分别为80.10%、83.70%。综合多项指标,夏枯草在各个方面表现能力均较强,可作为滨岸缓冲带的备选植物。

In order to establish effective water works in riparian buffer zones,five economic hydrophytes,Melilotus suaveolens Ledeb.,Trifolium repens L.,Mentha sachalinensis （Briq.） Kudo,Digitaria sanguinalis （L.） Scop.and Prunella asiatica Nikai,were selected to carry out a research on the bio-ecological characteristics and the nitrogen and phosphorus absorption capacity.Results show that the root,stem and detached leaf of each species exhibit different degrees of growth.Moreover,each species shows definite absorption effect of ammonia nitrogen and soluble phosphate.In low nitrogen and phosphorus conditions,M.suaveolens and T.repens have superior absorptive capacity toward ammonia nitrogen and soluble phosphate,with absorption rates of ammonia nitrogen and soluble phosphate of 75.69% and 56.81%,respectively;while in medium and high level conditions,P.asiatica exhibits absorption rates of ammonia nitrogen of 73.76% for medium level and 71.85% for high level,and those of soluble phosphate are as high as 80.10% and 83.70%,respectively.It is concluded that P.asiatica can be selected as an alternative plant for riparian buffer strips because of its good performances in various aspects.