春季水库浮游生物与鲢鳙生长的关系

通过 2 0 0 0年春季对辽宁三座大中型山谷型水库的浮游生物和鲢鳙渔获物的 4、5月二次调查发现 :( 1) . 4月 ,各水库浮游植物生物量与其鲢鳙年平均渔获量正相关 ( p<0 .10 ) ,同时发现浮游植物在各水库的空间分布与环境因子无显著关系 ,浮游植物与浮游动物之间只有在产量较低的碧流河水库有极其显著的正相关关系 ( p<0 .0 1) ;但此时三水库浮游动物生物量的空间分布都与水温或流速相关显著 ( p<0 .0 5 ) ;( 2 ) . 5月 ,这种现象消失 ,而发现浮游植物多样性指数较 4月的比值与渔获量存在极显著的负相关关系 ( p<0 .0 1) ,浮游植物量空间分布的变异性与渔获量存在极显著的负相关关系 ( p<0 .0 2 ) ,浮游动物空间分布变异性与 4月的比值与渔获量存在显著负相关关系 ( p<0 .0 7) ;而且只有在鱼产量最低的碧流河水库显示了浮游动物生物量的空间分布与环境因子 (水温 )相关 ( p<0 .10 ) ;( 3) .鲢鳙肥满度和增重率显示与上述结果相对应 ,即浮游生物空间分布越不均匀 ,浮游植物的多样性指数随着温度的升高幅度越大的水库 ,鲢鳙的生长速度越快。认为 :1.鲢鳙的摄食 ,导致浮游生物的空间分布更均匀 ,而且使浮游植物的多样性受到限制 ;2 .用浮游生物空间分布的不均匀程度以及多样性指数的变化 ,可以用来评价和指导

RELATIONSHIP OF PLANKTON IN SPRING WITH THE GROWTH OF SILVER CARPS AND BIGHEAD CARPS

Twice investigating the plankton communities of three Liaoning reservoirs in the spring of 2000, we obtain the following results. (1) In April, the biomass of phytoplankton has a positive correlation with the production of the fish (p<0.10), and the spatial distribution of plankton has no correlation with the environmental factors, while in the reservoir with the lowest fish production (FP) the biomass of zooplankton is significantly positively-correlative with the biomass of phytoplankton (p<0.01). (2) In May, this phenomenon disappears whereas the phytoplankton diversities and the ratios of coefficient of variability (CV) of zooplankton in April and May and the CV of phytoplankton have a significant negative-correlation with the FP (p<0.01, p<0.07, p<0.02). The correlation of plankton with the environmental factor could only be observed in Reservoir Biliuhe, which has the lowest FP, where the biomass of zooplankton has a correlation to the water temperature (p<0.10). (3). An analysis of fish capture reveals that the fish grow faster in reservois where the biodiversity of phytoplankton increases greater with rising temperature and the CV of plankton remains larger. From the above results, we come to the following conclusions. (1) The feeding of silver carp and bighead carp makes the biomass of plankton distribute more evenly in space and plankton diversity restricted. (2) An analysis of the variability and diversity of plankton is of significance in guiding the pasture of silver carps and bighead carps.