螺形龟甲轮虫形态结构对环境变化的响应

以螺形龟甲轮虫为研究对象，于2015年7月至2018年12月，选取广东南澳岛及湖南常德中营养至中度富营养水体共14个样点进行采样，对螺形龟甲轮虫进行了形态特征测量分析.结果表明，水温是螺形龟甲轮虫形态变化最主要影响因子，且与背甲长、背甲宽、棘刺长度均呈显著负相关（P<0.01）.不同纬度条件下螺形龟甲轮虫形态参数差异显著，常德地区螺形龟甲轮虫个体显著大于南澳地区（P<0.05）.螺形龟甲轮虫形态存在显著季节性变化，各形态参数随季节波动呈现夏秋、冬春分化模式.螺形龟甲轮虫后棘刺长随水体营养程度增加而减小（F=159.4，P<0.01），富营养条件下后棘刺长度占全长的比例减小（F=167.5，P<0.01）.研究结果表明，螺形龟甲轮虫棘刺长度可作为水质生物监测指标，并为研究全球气候变暖提供重要参考.

The responses of morphological variation of Keratella cochlearis to environmental changes

In this study, to measure and analyze the morphometric parameters of K.cochlearis, 14sites were selected in Nan'ao Island, Guangdong Province and Changde city, Hunan Province with different water trophic statuses from mesotrophic to moderate-eutrophic. Samples were collected quarterly from July 2015 to December 2018. The results showed that the water temperature was the most important factor affecting the morphological changes of K.cochlearis and had a significant negative correlation with lorica length, lorica width and spine length (P<0.01). There were significant differences in morphometric parameters of K.cochlearis in different latitudes, with individuals from Changde area being significantly larger than those in Nan'ao (P<0.05). There were also significant seasonal changes in the morphology of K.cochlearis, and the morphological parameters of this species showed different pattern between summer-autumn and winter-spring. The length of the posterior spines of K.cochlearis decreased with the increased of nutrient loading (F=159.4, P<0.01), and the ratio of the length of the posterior spines to the total length of rotifer decreased under eutrophic condition (F=167.5, P<0.01). The results showed that the spine length of K.cochlearis can be used as a biological monitoring index of water quality, and provided an important reference for the study of global warming.