水培蕹菜与微型生物种群的相互影响

[目的]研究水蕹菜与蓝藻、绿藻和轮虫之间的关系及净水机制。[方法]以水蕹菜为试验材料,利用水培生态模拟的方法将小球藻、斜生栅藻、铜绿微囊藻和蛭形轮虫添加到水蕹菜培养液中,通过测定水蕹菜的生长指标、微型生物种群变化以及营养液内的营养消耗状况,研究水蕹菜同微型生物种群间的相互作用。[结果]水蕹菜苗株根系发育到一定阶段,主根生长停滞而侧根大量萌出,营养吸收效率增大。当初始接种浓度为10.0×104cells/ml时,小球藻刺激水蕹菜快速生长,根系及茎叶系统发达茂密,但后期高密度小球藻的营养竞争则导致水蕹菜生长减缓。混合藻的竞争及化感作用限制了水蕹菜根系发展。蛭形轮虫繁殖产生的摄食压力对铜绿微囊藻影响较小,却抑制了斜生栅藻的生长。蛭形轮虫的粘附及摄食作用对水蕹菜根系的影响明显,导致茎叶系统发育不良,生物量下降。[结论]该研究可为鱼虾菜生态养殖模式的推广应用提供数据支持。

Interactions between lpomoea aquatica in Hydroponic Culture and Microbial Populations

[ Objective ] The research aimed to study water purification mechanism of Ipomoea aquatica and the correlations between L aquati- ca and cyanobacteria, green algae and rotifer. [ Method ] Taking Ipomoea aquatica as test materials, Chlorella vulgaris, Scenedesmus obliquus, Microcystis aeroginosa and Adineta vaga were added in the water culture solution of 1. aquatica by hydroponic ecological simulation method. The growth characteristics of I. aquatica, changes of microbial populations and the consumption situations of nutrients in the nutritional solution were determined. The interactions between I. aquatica and microbial population were studied. [ Result] When the growth development of I. aquatica seedlings reached certain stage, the main root of I. aquatica seedlings stopped growing and the lateral root developed rapidly with high adsorption efficiency of nutrients. When the initial inoculation concentration was 10.0 × 10^4 cells/ml, C. vulgaris simulated the rapid growth of I. aquatica and root, stem and leaves rapidly developed. In late stage, the nutrient competition of high-density C. vulgaris inhibited the growth of I. aquatica. The competition and allelopathic effects of mixed algae restrained the root growth of I. aquatica. The feeding pressure produced by the propagation of A. vaga had less influences on M. aeroginosa, but it inhibited the growth of S. obliquus. The adhesive and feeding effects of A. vaga had obvious effects on the root of 1. aquatica, which inhibited the growth of stem and leaf system and decreased the biomass. [ Conclusion] The research could provide data support for the popularization and application of fish-shrimp-vegetables ecological cul- ture model.