Nutrients and chlorophyll-a dynamics in a temperate reservoir influenced by Asian monsoon along with in situ nutrient enrichment bioassays

Jae Hoon Lee, Ja Myung Kim, Dong Su Kim, Soon Jin Hwang, Kwang Guk An

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

Long-term nutrients and chlorophyll-a dynamics during 1993-2000 were analyzed in a temperate reservoir influenced by the Asian monsoon. Nonparametric Mann-Kendall tests and seasonal trend analyses indicated that there were no long-term annual increasing or decreasing trends in major trophic parameters over 8 years, but the monsoon seasonality was evident. Seasonality in chlorophyll (CHL) and total phosphorus (TP) showed a mono-modal pattern, which was closely associated with the monsoon season of July-August, and the magnitude of the mono-modal peak was greater in the headwater zone than in the downlake zone. Such temporal patterns fluctuated interannually over the study period, and the magnitude of the variation was directly controlled by the intensity of the monsoon rain. Empirical models of annual mean CHL-TP were developed supporting the view that phytoplankton in lentic ecosystems responds to P enrichment and that annual mean TP may provide a reliable basis for predicting the average algal abundance. Ambient nutrient analyses, N:P ratios and in situ nutrient enrichment bioassay experiments (NEBs) in premonsoon and postmonsoon supported the P limitation for phytoplankton growth. Ambient nutrients and non-volatile suspended solid (NVSS) data on CHL in the intense monsoon year, however, showed the possibility of light limitation, even though the NEBs did not show the direct evidence. These findings were confirmed by two-dimensional graphic approaches of trophic state index deviations (TSIDs).

Original languageEnglish
Pages (from-to)49-62
Number of pages14
JournalLimnology
Volume11
Issue number1
DOIs
StatePublished - Jan 2010

Keywords

  • Chlorophyll-a
  • Nutrient bioassay
  • Seasonality
  • Trophic state
  • Water quality

Fingerprint

Dive into the research topics of 'Nutrients and chlorophyll-a dynamics in a temperate reservoir influenced by Asian monsoon along with in situ nutrient enrichment bioassays'. Together they form a unique fingerprint.

Cite this