三峡水库汉丰湖溶解态硅、氮、磷浓度及生态化学计量时空变化特征
Temporal and Spatial Characteristics of Dissolved Silicon,Nitrogen and Phosphorus Concentrations and Ecological Stoichiometry in the Hanfeng Lake of the Three Gorges Reservoir
朱舜垚 1梁珂 1何丙辉 1李天阳 1赵秀兰 1吴浩晨1
作者信息
- 1. 西南大学资源环境学院,重庆 400715
- 折叠
摘要
明确水体中典型营养盐成分如硅(Si)、氮(N)、磷(P)及其生态化学计量时空变化特征,将有助于探究水体富营养化程度及浮游植物营养限制状态.在三峡水库汉丰湖设7个采样点,于2020年5月～2021年4月取样后测定可溶性硅酸盐(DSi)、可溶性总氮(DN)、可溶性总磷(DP)、叶绿素a(Chl-a)等指标的浓度时空变化特征,通过Si、N、P的生态化学计量关系,评估水体浮游植物养分限制状态.结果表明:在时间变化上,水体中DSi月平均浓度为18.80 mg·L-1,8月最低,11月最高,在季节上呈现夏季最低,秋季最高的特征.DN、DP月平均浓度分别为1.57 mg·L-1、0.09 mg·L-1,两者季节变化相似,均呈现冬春季高,夏秋季低的特点.Chl-a月平均浓度为4.48 μg·L-1,夏季最高,秋季最低,与DSi浓度的季节变化正好相反,且二者呈显著负相关.在空间上,位于南河断面的DSi、DN、DP浓度均大于其它断面,DSi可能少部分来自沉积物的分解释放,大部分通过地表径流的形式,由陆地向水体进行补充.DSi/DN全年均值为6.47,2月最低,11月最高.DN/DP在1月最低,7月最高,全年均值为47.76.研究结果表明汉丰湖浮游植物生长的主要限制因素是P元素.
Abstract
Clarifying the typical nutrient components of silicon(Si),nitrogen(N)and phosphorus(P)in water and their temporal and spatial changes of ecological stoichiometry is helpful to explore the degree of eutrophication and the limiting state of phytoplankton nutrition.In this study,seven sampling sites were set up in Hanfeng Lake of the Three Gorges Reservoir.The temporal and spatial variation characteristics of concentrations of soluble silicate(DSi),soluble total nitrogen(DN),soluble total phosphorus(DP),chlorophyll a(Chl-a)and other indicators were measured via sampling from May 2020 to April 2021.The phytoplankton nutrient restriction status in water was assessed through the establishment of ecological stoichiometry relationship of Si,N and P.The results showed that the monthly average concentration of DSi was 18.80 mg/L with the lowest value in August and the highest in November.At the seasonal scale,this value was the lowest in summer and the highest in autumn.The monthly mean concentrations of DN and DP were 1.57 mg/L and 0.09 mg/L,respectively.The seasonal variations of DN and DP were similar,with high concentrations in winter and spring and low concentrations in summer and autumn.The monthly average concentration of Chl-a was 4.48 μg/L,with the highest in summer and the lowest in autumn,showing an opposite to the seasonal variation of DSi concentration,and a significant negative correlation.In space,the concentrations of DSi,DN and DP in Nanhe section were all higher than those in other sections.A small part of DSi might come from the release of sediment decomposition,and a large part of DSI was supplemented from land to water body via surface runoff.The mean value of the ratio of DSi/DN for the whole year was 6.47,with the lowest value in February and the highest in November.The ratio of DN/DP was the lowest in January and the highest in July,with an annual average of 47.76.The results indicated that the main limiting factor of phytoplankton growth in Hanfeng Lake was element P.
关键词
汉丰湖/浮游植物/生态化学计量/养分限制/水环境/富营养化Key words
Hanfeng Lake/phytoplankton/ecological stoichiometry/nutrient restriction/water environment/eutrophication引用本文复制引用
基金项目
国家自然科学基金项目(U20A20326)
国家自然科学基金项目(42107347)
重庆市教委科学技术研究项目(KJQN202100212)
出版年
2024
NETL
NSTL
万方数据