杨树、刺槐混交及缺钾情况下对矿物钾的利用

Studies on the Uptake of Mineral K by Mixed-plantings of Poplar and Black Locust Under K-deficiency

本文通过沙培盆栽试验研究了１年生杨树、刺槐及两者混植对矿物Ｋ的利用，并采用封闭循环系统对树木生长过程中不同形态的变化进行了严格的数量化研究，同时研究了缺Ｋ胁迫下对矿物Ｋ的利用及对Ｎ，Ｐ，Ｋ积累的影响．结果表明：杨树、刺槐都可不同程度吸收矿物Ｋ，两者混交后利用矿物Ｋ的量有很大提高；缺Ｋ胁迫可提高植物吸收矿物Ｋ的量；缺Ｋ主要抑制根系生长，对地上部分影响较小；Ｋ元素对Ｎ的影响较大，对Ｐ的影响较小．

One-year-old poplar and black locust grown in sand culture with closed cycling ofmineral nutrients were used to study the uptake of mineral K,and the effect of mixed-plantingand K-deficiency on uptake and accumulation of N,P,K.Results showed that both species hadthe ability to uptake mineral K,but at different rates. K uptake was significantly promoted bythe plants in mixed-planting and under K-deficiency.K-deficiency depressed mainly root growthand shcot growth was less affected.K-deficiency affected N uptake more than P uptake.