随着人类活动对珊瑚礁的影响日益加剧,输入到近岸珊瑚礁区的悬浮物日益增多,不仅影响珊瑚的生理,也会对珊瑚礁生态系统基础生物生产过程产生影响.为了解悬浮物对珊瑚礁区浮游动物组成及摄食的影响,于 2015 年 4 月在三亚典型岸礁区设置了昼夜连续观测站点(W4为悬浮物浓度高的站位,W5为对照站位),分析了悬浮物波动对浮游动物群落结构的影响,并用分子生物学方法结合室内实验,研究了悬浮物对优势桡足类现场食物组成和摄食选择的影响.结果显示:两个站位叶绿素 a 浓度偏低,昼夜波动较大;W4 站的悬浮物和叶绿素 a 浓度均高于 W5 站,但 W5 站悬浮物中有机颗粒物组分比例(73.69%)高于W4站(46.09%);W5站浮游动物种类多样性和丰度均高于W4站.进一步摄食分析表明,两个站位桡足类均以后生动物来源的有机碎屑为主要食物,在 W4 站桡足类食物组成中浮游植物的比例也相对较高,而在 W5 站桡足类还摄食较多的微型浮游动物.在摄食实验中,高浓度的悬浮颗粒物显著提高了红纺锤水蚤(Acartia erythraea)的滤水率和摄食率,但其食物组成却由以浮游植物为主转而以陆生植物碎屑为主,说明浓缩海水中较高的悬浮颗粒物含量限制了桡足类的摄食选择,使其摄食大部分有机碎屑作为补偿营养来源.研究结果表明,高悬浮物浓度会影响浮游动物的摄食选择,但悬浮物中高比例的有机碎屑可为浮游动物提供重要的补充食物来源,支持其维持较高的生物量.
Effect of suspended solids on zooplankton community and their feeding selectivity in the Sanya coral waters
With the intensification of human activities,the suspended solids imported into the nearshore coral reef area are increasing,which will not only affect the physiology of coral but also affect the basic biological production process of the coral reef ecosystem.To understand the impact of suspended solids on the species composition and feeding of zooplankton,the impact of suspended solids fluctuation on zooplankton community structure was analyzed by a diurnal observation in a typical coastal reef area of Sanya in April 2015,and the feeding response of the dominant species was studied by molecular method combined with laboratory experiments.The results showed that the phytoplankton biomass(chlorophyll a concentration)in these two stations was low with a significant diurnal fluctuation.The concentration of suspended solids and chlorophyll a in the W4 station are higher than those of the W5 station,but the proportion of organic particulate matter in the suspended solids of the W5(73.69%)station is higher than that of W4(46.09%).The species diversity and abundance of zooplankton in the W5 station are higher than that in the W4 station.Dietary analysis shows that the copepods in these two stations are mainly fed on organic detritus from metazoans.The proportion of phytoplankton in the diet of copepods in the W4 station is also relatively high,while copepods in the W5 station also eat some microzooplankton.In the feeding experiment,the high concentration of suspended particles significantly improved the filtration rate and ingestion rate of Acartia erythraea,but its dominant food item changed from phytoplankton to terrestrial plant detritus,indicating that the high content of suspended particles in the concentrated seawater limited the feeding choice of copepods and made them eat more organic detritus as a compensatory food source.The results show that high suspended solids concentration will affect the feeding choice of zooplankton,but the high proportion of organic detritus in suspended solids can provide an important supplementary food source for zooplankton and support its maintenance of high biomass.
zooplanktonsuspended solidcommunity structurediet diversitySanya Bay
万方数据
维普
