pH及无机氮化合物对细脉浮萍生长的影响

研究以细脉浮萍 ( Lemna aequinoctialis)为研究对象 ,在完全培养液的基础上模拟生活污水的氨氮、硝酸氮浓度和 p H范围 ,研究了培养条件对其生长的影响。结果表明 ,这个浮萍种对 p H耐受的低限在 4～ 5之间 ,最适 p H范围为 5～ 6。非离子态的氨会对其生长产生抑制作用 ,在氨氮为唯一氮源的条件下 ,非离子态氨的浓度大于 0 .1 mg/L时会对此种的生长产生明显的抑制作用 ,接近 2 mg/L时 ,基本上致死。在研究的氨氮和硝酸氮浓度范围内 ( <40 mg N /L) ,铵根离子和硝酸根离子浓度增加可促进细脉浮萍的生长。氨氮中生长的植株过氧化物酶活性高于硝酸氮中的活性。

Effects of inorganic nitrogen compounds and pH on the growth of duckweed Lemna aequinoctialis

Duckweed has a good potential to recover nutrients from the domestic wastewater. However, inorganic nitrogen compounds and pH of the wastewater may affect the growth of duckweed. In this study, we have investigated the effects of the above two parameters on the growth of Lemna aequinoctialis, a duckweed species from South China. The duckweed was collected from a wetland nearby Dianchi Lake in Yunnan, China, where it existed together with Lemna minor and Spirodela polyrrhiza which are common duck...