Premium
Relationships between microcystins and environmental parameters in 30 subtropical shallow lakes along the Yangtze River, China
Author(s) -
WU S. K.,
XIE P.,
LIANG G. D.,
WANG S. B.,
LIANG X. M.
Publication year - 2006
Publication title -
freshwater biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.297
H-Index - 156
eISSN - 1365-2427
pISSN - 0046-5070
DOI - 10.1111/j.1365-2427.2006.01652.x
Subject(s) - microcystis , microcystin , cyanobacteria , anabaena , subtropics , environmental science , lake ecosystem , eutrophication , ecology , yangtze river , phosphorus , biology , hydrology (agriculture) , environmental chemistry , nutrient , ecosystem , geography , china , chemistry , geology , genetics , geotechnical engineering , organic chemistry , bacteria , archaeology
Summary 1. A survey of 30 subtropical shallow lakes in the middle and lower reaches of the Yangtze River area in China was conducted during July–September in 2003–2004 to study how environmental and biological variables were associated with the concentration of the cyanobacterial toxin microcystin (MC). 2. Mean MC concentration in seasonally river‐connected lakes (SL) was nearly 33 times that in permanently river‐connected lakes (RL), and more than six times that in city lakes (NC) and non‐urban lakes (NE) which were not connected to the Yangtze River. The highest MC (8.574 μ g L −1 ) was detected in Dianshan Lake. 3. MC‐RR and MC‐LR were the primary toxin variants in our data. MC‐RR, MC‐YR and MC‐LR were significantly correlated with Chl a , biomass of cyanobacteria, Microcystis and Anabaena , indicating that microcystins were mainly produced by Microcystis and Anabaena sp. in these lakes. 4. Nonlinear interval maxima regression indicated that the relationships of Secchi depth, total nitrogen (TN) : total phosphorus (TP) and NH with MC were characterised by negative exponential curves. The relationships between MC and TN, TP, NO + NO were fitted well with a unimodal curve. 5. Multivariate analyses by principal component and classifying analysis indicated that MC was mainly affected by Microcystis among the biological factors, and was closely related with temperature among physicochemical factors.