Influence of environmental variables on macroinvertebrate community
structure in Lianhuan Lake
Abstract
The characteristics of macroinvertebrate community structure can
effectively reflect the health status of lake ecosystem and the quality
of the lake ecological environment. It is of great significance to
identify the limiting factors of macroinvertebrate community structure
for the maintenance of lake ecosystem health. In this study, the
community composition of macroinvertebrate assemblages and their
relationships with environmental variables in 13 small lakes within
Linhuan Lake was investigated. Self-organizing map, K-means clustering
analysis, principal component analysis, pearson correlation analysis,
and redundancy analysis were used to analyze the correlation and
variability between macroinvertebrates community index and environmental
factors. The results showed that the environmental variables (pH, total
phosphorus, nitrate, water temperature, dissolved oxygen, conductivity,
chemical oxygen demand, and ammonium) had a significant effect on the
classification of macroinvertebrate community. Molluscs were
significantly negatively correlated with pH and chlorophyll a, while
annelids and aquatic insects were significantly positively correlated
with chlorophyll a and dissolved oxygen. Species richness and Shannon’s
diversity of macroinvertebrates were significantly negatively correlated
with total phosphorus while biomass of macroinvertebrates was
significantly negatively correlated with pH. High alkalinity
characteristics and eutrophication of the lake have a serious impact on
the macroinvertebrate community. Human interference and unreasonable
industrial and surface runoff from agricultural farms destroy the
ecological environment and affect the community structure of
macroinvertebrate. Thus, the improvement of the macroinvertebrate’s
community structure should be carried out by improving the Lianhuan Lake
watershed ecological environment and controlling watershed environmental
pollution.