嘉陵江南充出境江段枯水期浮游生物群落结构及水质评价

Plankton Community Structure and Water Quality Assessmentof Nanchong Outbound Section of Jialing River in Dry Season

为了解嘉陵江南充出境段枯水期水质状况及浮游生物群落结构现状,于2022年冬季在嘉陵江南充出境江段调查了9项常规理化指标,并计算了多样性指数,结果表明:枯水期嘉陵江南充出境江段水质符合单指标评价Ⅱ类标准;浮游植物共126种(变种),隶属于7门19目33科66属,水体属于硅藻-绿藻-蓝藻型,浮游植物的总平均密度为(42.55±13.81)×10^(4)ind.·L^(-1),总平均生物量为(0.55156±0.16307)mg·L^(-1);浮游动物共37种,以轮虫为主(占48.56%),总平均密度为(47.80±14.78)ind.·L^(-1),总平均生物量为(0.16261±0.06635)mg·L^(-1);着生藻类共74种(变种),隶属于5门14目20科32属,总平均密度为(15.31±4.81)×10^(4)ind.·cm^(-2),总平均生物量为(0.28470±0.09390)mg·cm^(-2);群落结构和多样性指数研究表明,该江段属于寡污型且处于中营养状态。

In order to know about the water quality and plankton community structure of Nanchong Outbound Section of Jialing River in dry season,nine conventional physical and chemical indicators of the river section were investigated in the winter of 2022 and the diversity index was also calculated.The results show that the water quality of Nanchong Outbound Section of Jialing River in the dry season has met Class II water quality standard of single index evaluation;there are 126 species(varieties)of phytoplankton,belonging to 7 phyla,19 orders,33 families,and 66 genera;the water body belongs to the diatom-green algae-cyanobacteria type;the total average density of phytoplankton is(42.55±13.81)×10^(4)ind.·L^(-1),and the total average biomass is(0.55156±0.16307)mg·L^(-1);there are 37 species of zooplankton,mainly rotifers(48.56%),and the total average density of zooplankton is(47.80±14.78)ind.·L^(-1)while the total average biomass is(0.16261±0.06635)mg·L^(-1);there are 74 species(varieties)of periphytic algae,belonging to 5 phyla,14 orders,20 families and 32 genera,and the total average density is(15.31±4.81)×10^(4)ind.·cm^(-2)while the total average biomass is(0.28470±0.09390)mg·cm^(-2).The study of community structure and diversity index indicates that the river section is in a mesotrophic state,belonging to the oligotrophic type.