Melzer A, Kaiser R
Institut für Botanik und Mikrobiologie der Technischen Universität München, Arcisstr. 21, D-8000, München 2, Germany.
Oecologia. 1986 Jul;69(4):606-611. doi: 10.1007/BF00410370.
11 macrophytic species from a groundwater influenced chalk stream in Upper Bavaria were investigated during a period of one year in order to determine differences in the endogenous nitrate content, in total nitrogen content and in nitrate reductase activity (NRA). Nitrate concentrations of different plants taken from the same site of the river varied by a factor of approximately 10. A maximum of 1,958 μmol NO g dry w. could be measured in the petioles of Nasturtium officinale, which accounts for 12% of plant dry w. Very high values were also found in Callitriche obtusangula and Veronica angallis-aquatica. In comparison to the ambient water, mean accumulation rates of up to 131 could be found. In Fontinalis antipyretica, the plant poorest in nitrate, the ratio was only 1.24:1. Elodea canadensis belonged to a group of plants having very low nitrate concentrations. Since NRA was very low too, it is assumed that nitrogen nutrition of this species depends rather on ammonia than on nitrate. With a few exceptions nitrate content of different plant organs varied markedly. In general they were lowest in leaves and highest in shoot axes. Appreciable amounts of nitrate were also found in the roots of plants. No correlation could be found between endogenous nitrate content and NRA. In contrast to endogenous nitrate content and NRA, total nitrogen concentrations of the plants did not differ significantly.
在一年的时间里，对来自上巴伐利亚州一条受地下水影响的白垩溪流中的11种大型植物进行了调查，以确定其内源硝酸盐含量、总氮含量和硝酸还原酶活性（NRA）的差异。从河流同一地点采集的不同植物的硝酸盐浓度相差约10倍。在水田芥的叶柄中测得的硝酸盐含量最高可达1958 μmol NO₃⁻ g干重，占植物干重的12%。钝头水马齿和水生婆婆纳中也发现了非常高的值。与周围水体相比，平均积累率高达131。在硝酸盐含量最低的真藓中，该比例仅为1.24:1。加拿大伊乐藻属于硝酸盐浓度非常低的一组植物。由于其NRA也很低，因此推测该物种的氮营养更多地依赖于氨而不是硝酸盐。除了少数例外，不同植物器官的硝酸盐含量差异明显。一般来说，它们在叶片中最低，在茎轴中最高。在植物的根中也发现了相当数量的硝酸盐。内源硝酸盐含量与NRA之间没有相关性。与内源硝酸盐含量和NRA不同，植物的总氮浓度没有显著差异。
