不同水深梯度对4种挺水植物生长繁殖的影响

Effects of water depth on the growth of four emergent macrophytes

选择了水葱(Scirpus validus)、菖蒲(Acorus calamus)、香蒲(Typha orientalis)、茭草(Zizania caduciflora)4种常见的挺水植物,研究了静水条件下不同水深梯度(0cm(对照)、30cm(浅水处理)、60cm(深水处理))对4种挺水植物生长和繁殖的影响.试验结果表明,深水处理对4种挺水植物的生长和繁殖都有显著的抑制作用;4种挺水植物通过增加地上部分的相对生物量、减少地下部分的相对生物量及增加地上部分的伸长生长来适应水深的增加;浅水处理茭草和香蒲的分蘖数较对照组总体差异不明显,而单株生物量总体较对照组大,在8、9月根状茎长度也较对照组大,认为茭草和香蒲的最适宜生长水深为30cm;与对照组相比,浅水处理的水葱根状茎长度、分蘖数总体均有减少,但单株生物量差异不大,认为水葱的最适宜生长水深为0cm;各个处理的菖蒲分蘖数几乎为零,浅水处理的菖蒲的根状茎长度、株高、单株生物量与其对照组的差异均较其他3种挺水植物小,认为0cm和30cm水深均适宜菖蒲生长,菖蒲对水位变化的形态可塑性能力小.

The effects of water depth gradient（0 cm,30 cm,60 cm） on vegetative growth and ramets of four typical emergent macrophytes（Scirpus validus,Acorus calamus,Typha orientalis,Zizania caduciflora） were examined in this study.We found that：1） deep water（60 cm） significantly reduced the growth and number of ramets in these four species;2） the species represented to increase shoot height along the water depth gradient,and there was a trade-off between the above and under ground parts;3） there were no differences in the number of ramets between shallow water（30 cm） and control（0 cm） groups in Z.caduciflora and T.orientalis,while individual biomass and rhizome length varied greatly;4） less ramets and shorter rhizomes were found in shallow water than control group in S.validus;5） A.calamus represented the lowest morphological plasticity along water depth gradient.We suggested that Z.caduciflora and T.orientalis would be favored at 30 cm depth,S.validus at 0 cm depth and A.calamus at both 0 cm and 30 cm depths.