穗花狐尾藻在不同营养水平湖泊繁殖策略的比较研究

研究资源在植物不同繁殖组分间的分配,初步了解水生植物在繁殖策略上适应富营养化的机制。试验地点为富营养化的星云湖和贫营养化的抚仙湖,各设置6个采样点,每个采样点在1.5 m水深处收集穗花狐尾藻10株,分为有性繁殖组分和无性繁殖组分,利用双因素方差分析比较穗花狐尾藻有性繁殖和无性繁殖的绝对生物量和相对生物量在不同采样点、不同营养化湖泊间的差异。穗花狐尾藻在抚仙湖有性繁殖的绝对生物量最高0.071 g、最低0.054 g,无性繁殖绝对生物量最高1.519 g、最低1.157 g;在星云湖有性繁殖的绝对生物量最高0.127 g、最低0.107 g,无性繁殖绝对生物量最高1.031 g、最低0.955。穗花狐尾藻在抚仙湖有性繁殖的比例最高为5.59%、最低为3.65%,无性繁殖比例最高为96.35%、最低为94.41%;在星云湖有性繁殖的比例最高为11.61%、最低为9.71%,无性繁殖最高为90.29%、最低为88.39%。穗花狐尾藻在富营养化湖泊星云湖将更多的资源投入到了有性繁殖,而在贫营养化湖泊抚仙湖则将更多的资源投入到无性繁殖。

Reproductive Strategies of Myriophyllum spicatum in Eutrophic and Oligotrophic Lakes: a Comparative Study

The resource allocation pattern among different reproductive components and the adaptive mechanism of the reproductive strategy to eutrophication of macrophytes were investigated in this study. This study took place at Xingyun Lake (eutrophicated lake) and Fuxian Lake (oligotrophicated lake). 6 sampling sites for each lake were set up and 10 individuals at 1.5m water depths of Myriophyllum spicatum for each site were collected. The individuals were divided into two: the sexual and asexual parts. The two way ANOVA was conducted to compare the differences of absolute biomass and relative biomass of these two parts among different sampling sites and different lakes. The results indicated that the highest and lowest absolute sexual biomass of M. spicatum were 0.071g and 0.054g respectively while 1.519g and 1.157g of asexual biomass in Fuxian Lake. These results changed to 0.127g and 0.107g of sexual biomass and 1.031 and 0.955g of asexual biomass in Xingyun Lake. Besides the absolute biomass, the ratio of biomass allocation indicated that the highest and lowest sexual ratio were 5.59% and 3.65% respectively while 96.35 and 94.41 of asexual ratio in Fuxian Lake. These results changed to changed to 11.61% and 9.71% of sexual ratio and 90.29% and 88.39% of asexual ratio in Xingyun Lake. Our results indicated that M. Spicatum allocated more to sexual reproduction in eutrophicated lake (Xingyun Lake) and more to asexual reproduction in oligotrophicated lake (Fuxian Lake).