Scholarlink

<p>For many years, excessive phytoplankton blooms have raised widespread public alarm. Based on monthly monitoring data from five fixed stations in Baihua Reservoir between January 2021 and December 2022, this study evaluated the seasonal dynamics of chlorophyll a (Chl.a) and its nonlinear responses to environmental drivers. We first applied Spearman rank correlation combined with variance-inflation-factor screening (VIF &lt; 5) to remove highly collinear predictors, then used Random Forest analysis to rank the remaining variables, identifying water temperature (WT), pH and total phosphorus (TP) as the primary drivers of Chl.a. A Generalized Additive Model (GAM) explained 56% of the variance in Chl.a, showing that Chl.a increased monotonically with WT between 10 and 18&#xa0;°C, rose almost linearly with pH from 7.8 to 8.4, and exhibited a threshold response as TP approached 0.04&#xa0;mg L⁻<sup>1</sup>. This study provides a fresh approach to assess the key factors influencing Chl.a and their interactions in Baihua Reservoir.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Nonlinear dynamics of chlorophyll a in relation to environmental factors in Baihua Reservoir

  • 期刊论文

  • 发表日期：

    2025年10月3日

查看全文
  • Wu Wei,
  • Mengshu Han,
  • Jing Xiao,
  • Weihua Ou,
  • Qiuhua Li

摘要

For many years, excessive phytoplankton blooms have raised widespread public alarm. Based on monthly monitoring data from five fixed stations in Baihua Reservoir between January 2021 and December 2022, this study evaluated the seasonal dynamics of chlorophyll a (Chl.a) and its nonlinear responses to environmental drivers. We first applied Spearman rank correlation combined with variance-inflation-factor screening (VIF < 5) to remove highly collinear predictors, then used Random Forest analysis to rank the remaining variables, identifying water temperature (WT), pH and total phosphorus (TP) as the primary drivers of Chl.a. A Generalized Additive Model (GAM) explained 56% of the variance in Chl.a, showing that Chl.a increased monotonically with WT between 10 and 18 °C, rose almost linearly with pH from 7.8 to 8.4, and exhibited a threshold response as TP approached 0.04 mg L⁻1. This study provides a fresh approach to assess the key factors influencing Chl.a and their interactions in Baihua Reservoir.