摘要
作者研究了有效碳（ＣＯ＿２、ＨＣＯ－＿３）对菹草光合作用及吸收氮、磷的影响。水中缺乏游离ＣＯ＿２时，菹草的光补偿点提高，光饱和点下降，对氮、磷营养盐的吸收速率显著降低。２５℃、最适光阴、强光而下，菹草进行正常氮代谢所需ＨＣＯ－＿３的临界浓度（ｍｍｏｌ·Ｌ￣（－１））分别为０．１８，０．２５；进行正常磷代谢所需ＨＣＯ－＿３的临界浓度（ｍｍｏｌ·Ｌ￣（－１））分别为０．３２，０．４０。不良光照和高ｐＨ下缺乏有效碳源使菹草的氮、磷代谢受阻而导致夏季菹草衰败死亡。
Effects of available carbons(CO_2,HCO-_3)on nitrogen and phosphorus uptaking and photosynthesis by Potamogeton crispus were investigated. The light compensation point of P. crispus increases, light saturation point decreases and the rate of uptake N and P nutrients by P. crispus descends in available carbon short-age in water.At a temperature of 25℃,under optimum light and high light in-tensity, HCO-_3 threshold concentration requirement for nitrogenous metabolism by P. crispus is 0.18 and 0.25 mmol·L￣(-1) and 0.32 and 0.40 mmol·L￣(-1)for phos-phorus metabolism, respectively.The metabolism of nitrogen and phosphorus for P.crispus is inhibited by ex-treme light,high pH and an carbon shortage. Therefore,P. crispus is getting at a low ebb and even death in summer.
出处
《大连水产学院学报》
CSCD
1994年第1期6-11,共6页
Journal of Dalian Fisheries University
基金
水电部科学发展基金
关键词
水生植物
菹草
有效碳
氮
磷吸收
Aquatic macrophytes
Potarnogeton crispus
Available corbon
Ni-trogen
Phosphorus uptake
