竞争条件下角突网纹溞和微型裸腹溞生活史策略对不同磷营养盐梯度的响应机制

The Response Mechanisms of Life-History Strategies in Ceriodaphnia cornuta and Moina micrura to Different Phosphorus Nutrient Gradients

摘要: 浮游动物在水生态系统的物质循环和能量流动中扮演着重要角色，其种群增长和群落结构对环境变化较为敏感，常被作为水环境监测中的重要指标生物。因此，探究环境因子对浮游动物种群增长的影响对水生态系统保护具有重要意义。为此，本研究以温州市三垟湿地为背景，采用室内模拟实验方法，选取了角突网纹溞(Ceriodaphnia cornuta)和微型裸腹溞(Moina micrura)作为室内实验受试生物，通过开展室内模拟实验，探究了不同磷营养盐浓度及种间竞争对两种枝角类浮游动物生活史策略的影响。主要研究结果如下：磷营养盐浓度与种间竞争对两种溞的生活史策略均产生显著影响，但响应模式存在明显物种差异。对角突网纹溞而言，磷浓度显著影响其种群增长参数与个体大小，高磷环境促进其性成熟体长增长与净繁殖率提升，而种间竞争对其影响主要体现在延迟首次繁殖日龄与缩短平均寿命。对微型裸腹溞来说，磷浓度升高反而导致其内禀增长率下降，低磷条件下其个体体型增大；种间竞争对其抑制作用更为强烈，显著降低其内禀增长率与净繁殖率。

Abstract: Zooplankton play a crucial role in the material cycling and energy flow of aquatic ecosystems. Their population growth and community structure are sensitive to environmental changes, making them important indicator organisms for water environment monitoring. Consequently, the influence of environmental factors on zooplankton population growth is of great significance for the conservation of aquatic ecosystems. We conducted laboratory simulation experiments using Ceriodaphnia cornuta and Moina micrura in this study based on the Sanyang Wetland in Wenzhou City, exploring the effects of different phosphorus nutrient concentrations and interspecific competition on the life-history strategies of these two cladoceran species. The main findings are as follows: The concentration of phosphorus and interspecific competition significantly influenced the life-history strategies of both cladoceran species, but the response patterns exhibited great differences among two species. For Ceriodaphnia cornuta, phosphorus concentration significantly affected its population growth parameters and individual size, with high phosphorus environments promoting the body length at maturity and net reproduction rate, while interspecific competition primarily manifested in delayed age at first reproduction and reduced average lifespan. For Moina micrura, increased phosphorus concentration conversely decreased its intrinsic growth rate, and low phosphorus conditions increase its individual body size, while interspecific competition exerted a more pronounced inhibitory effect, significantly reducing its intrinsic growth rate and net reproduction rate.