Scholarlink

<p>Sustained eutrophication in low-phosphorus (P &lt; 1 μM and phosphate (PO<sub>4</sub><sup>3</sup>⁻) &lt;0.2 μM) lakes poses a challenge to understanding P cycling in stratified lakes. Conventional P concentration and low vertical-resolution phosphate oxygen isotope data (<i>δ</i><sup>18</sup>O<sub>P</sub>) cannot solve this problem. Here, we measured high-resolution <i>δ</i><sup>18</sup>O<sub>P</sub> profiles in two typically low-P, eutrophic, thermally stratified lakes (Lake Hongfeng and Lake Aha, China) via a newly developed ESI-Orbitrap-MS technique. The lakes showed high <i>δ</i><sup>18</sup>O<sub>P</sub> values (19.3‰−19.8‰) at the surface (0–2 m), but low values (13.4‰−13.7‰) at thermocline. A one-dimensional concentration-<i>δ</i><sup>18</sup>O<sub>P</sub> coupled diffusion model constrains an apparent kinetic isotope effect of 0.9932 and 0.9906 for biological surface uptake and thermocline remineralization, respectively. The results suggest that eutrophication was sustained by a rapid PO<sub>4</sub><sup>3–</sup> uptake by algae at surface and remineralization of organic P at depth. This study provides isotope evidence for P cycling dynamics in low-P natural lakes with excessive algae growth.</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

Phosphorus cycling dynamics in stratified low-phosphorus lakes

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月4日

查看全文
  • Zhao Wei,
  • Baoying Wang,
  • Hao Yan,
  • Longchen Zhu,
  • Yu Wei,
  • Yankai Shang,
  • Huiming Bao

摘要

Sustained eutrophication in low-phosphorus (P < 1 μM and phosphate (PO43⁻) <0.2 μM) lakes poses a challenge to understanding P cycling in stratified lakes. Conventional P concentration and low vertical-resolution phosphate oxygen isotope data (δ18OP) cannot solve this problem. Here, we measured high-resolution δ18OP profiles in two typically low-P, eutrophic, thermally stratified lakes (Lake Hongfeng and Lake Aha, China) via a newly developed ESI-Orbitrap-MS technique. The lakes showed high δ18OP values (19.3‰−19.8‰) at the surface (0–2 m), but low values (13.4‰−13.7‰) at thermocline. A one-dimensional concentration-δ18OP coupled diffusion model constrains an apparent kinetic isotope effect of 0.9932 and 0.9906 for biological surface uptake and thermocline remineralization, respectively. The results suggest that eutrophication was sustained by a rapid PO43– uptake by algae at surface and remineralization of organic P at depth. This study provides isotope evidence for P cycling dynamics in low-P natural lakes with excessive algae growth.