Data from: Zooplankton species diversity in the temporary wetland system of the Savannah River Site, South Carolina, USA

Understanding how diverse species communities develop and how the species within them coexist is one of the central questions in community ecology. The temporary wetland system occurring on the Savannah River Site near Aiken, South Carolina is home to the most species rich temporary wetland zooplankton assemblage known in the world. While previous research has documented this remarkable diversity, there has been little study directed at understanding how diversity is distributed at the landscape and local scales or on investigating potential mechanisms of what has led to the high richness of this system. The collection of studies presented here examine diversity patterns in the zooplankton community, links these patterns to spatial and temporal variation, experimentally tests the effects of two important environmental factors on diversity, and describes two new species. Results indicate that long hydroperiod lengths were associated with high species richness. Wetlands with similar species assemblages were generally closer together, suggesting the importance of dispersal. Over the course of a year, diversity increased during the spring and summer months and declined toward the fall, these changes were associated with low pH, low conductivity, and high water temperature. Vegetated areas within wetlands had greater diversity than did unvegetated areas, and diversity was particularly low in areas of decaying vegetation. Temporal comparisons provide evidence for distinct seasonal communities that arise every year. Experimental tests of the impact of hydroperiod length on diversity found that shorter hydroperiods resulted in reduced species richness, and communities dominated by just a few species. Predation was found to have no effect on diversity or community composition. During investigation of the diversity of these wetlands, two new species of the genus Chydorus were discovered and described. These two species differ from congeners both in morphology and phylogenetically. Together these studies describe how environmental variation can impact the diversity of the zooplankton communities within temporary wetlands and show how hydroperiod limits the richness of these systems. The results presented here provide insight into the forces that may lead to diverse communities in temporary wetlands, providing direction for future research into these dynamic ecosystems.解析多样物种群落的构建机制及其内部物种的共存模式，是群落生态学的核心研究议题之一。坐落于南卡罗来纳州艾肯市附近萨凡纳河场址的暂时性湿地系统，拥有全球已知物种多样性最高的暂时性湿地浮游动物(zooplankton)集合群。尽管既往研究已记录了该系统的极高物种多样性，但目前鲜有研究探讨多样性在景观尺度与局地尺度的分布格局，亦未阐明驱动该系统高物种丰富度的潜在机制。本系列研究聚焦浮游动物群落的多样性格局，将其与空间、时间变异相关联，通过实验验证了两类关键环境因子对多样性的影响，并描述了两个新物种。研究结果显示，较长的淹水期长度(hydroperiod)与较高的物种丰富度呈显著关联。物种集合群相似的湿地通常空间距离更近，这表明扩散过程的重要性。在全年周期中，多样性在春季与夏季呈上升趋势，秋季则逐渐下降；这类变化与低pH值、低电导率(conductivity)及高水温显著相关。湿地内的植被覆盖区域较无植被区域具有更高的多样性，而枯落植被覆盖区域的多样性尤为低下。时间序列对比分析表明，该系统每年都会形成特征鲜明的季节性群落。针对淹水期长度对多样性影响的实验验证表明，较短的淹水期会导致物种丰富度降低，且群落会被少数物种主导。捕食作用对群落多样性与组成均无显著影响。在对这些湿地多样性的调查过程中，研究人员发现并描述了盘肠蚤属(Chydorus)的两个新物种。这两个新物种在形态学与系统发育特征上均与其同属物种存在显著差异。综上，本系列研究阐明了环境变异如何影响暂时性湿地内浮游动物群落的多样性，并揭示了淹水期长度如何限制该系统的物种丰富度。本研究结果为解析暂时性湿地多样物种群落的形成机制提供了新视角，也为这类动态生态系统的后续研究指明了方向。