Scholarlink

<p>Bitumen extraction from oil sands surface mining in northern Alberta generates vast amounts of oil sands process-affected water (OSPW) containing naphthenic acid fraction compounds (NAFCs) that require treatment due to their persistence and toxicity. The use of constructed wetland treatment systems (CWTS) is a promising strategy for reducing NAFC concentrations in OSPW. Photosynthetic microalgae and cyanobacteria are present in CWTS, yet their contributions to this ecosystem and NAFC degradation remain understudied. We investigated the temporal dynamics of phytoplankton communities within a pilot CWTS treating OSPW to characterize these organisms and their potential contributions to NAFC transformation. Phytoplankton taxa identified were comparable to those found in natural boreal lakes, including Chlorophyta, Cryptophyta, and photosynthetic Stramenopiles/marine algae (e.g., Chrysophyceae, Xanthophyceae, and Eustigmatophyceae) and Cyanobacteria. Water chemistry, particularly pH, calcium, magnesium, sodium, temperature, electrical conductivity, and NAFC concentrations, played a key role in shaping phytoplankton communities. While magnesium and calcium supported long-term algal growth and resilience, NAFC concentrations strongly influenced early-stage community composition. As NAFC concentrations declined over time, their direct impact lessened, highlighting phytoplankton adaptability to shifting environmental conditions. Over the operational season, NAFC concentrations in the CWTS decreased by approximately 35%, accompanied by a shift in NAFC class distribution. The toxic O<sub>2</sub> class declined, while higher-oxygenated, less toxic classes (O<sub>3</sub>, O<sub>4</sub>, O<sub>5</sub>, O<sub>6</sub>) increased, suggesting microbial and algal-mediated transformation. Several algal genera exhibited significant correlations with heteroatom composition at different time points, with <i>Ankistrodesmus</i>, <i>Scotinosphaera</i>, and <i>Chloroidium</i> significantly associated with NAFC biodegradation products at the end of the CWTS operating season. These findings suggest that phytoplankton may contribute to NAFC transformation, supporting their contribution to degradation of OSPW components in constructed wetlands.</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

Phytoplankton community dynamics and their role in naphthenic acid transformation within a constructed wetland system treating oil sands process-affected water

  • 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
  • Dilini M. Atugala,
  • Lisa M. Gieg

摘要

Bitumen extraction from oil sands surface mining in northern Alberta generates vast amounts of oil sands process-affected water (OSPW) containing naphthenic acid fraction compounds (NAFCs) that require treatment due to their persistence and toxicity. The use of constructed wetland treatment systems (CWTS) is a promising strategy for reducing NAFC concentrations in OSPW. Photosynthetic microalgae and cyanobacteria are present in CWTS, yet their contributions to this ecosystem and NAFC degradation remain understudied. We investigated the temporal dynamics of phytoplankton communities within a pilot CWTS treating OSPW to characterize these organisms and their potential contributions to NAFC transformation. Phytoplankton taxa identified were comparable to those found in natural boreal lakes, including Chlorophyta, Cryptophyta, and photosynthetic Stramenopiles/marine algae (e.g., Chrysophyceae, Xanthophyceae, and Eustigmatophyceae) and Cyanobacteria. Water chemistry, particularly pH, calcium, magnesium, sodium, temperature, electrical conductivity, and NAFC concentrations, played a key role in shaping phytoplankton communities. While magnesium and calcium supported long-term algal growth and resilience, NAFC concentrations strongly influenced early-stage community composition. As NAFC concentrations declined over time, their direct impact lessened, highlighting phytoplankton adaptability to shifting environmental conditions. Over the operational season, NAFC concentrations in the CWTS decreased by approximately 35%, accompanied by a shift in NAFC class distribution. The toxic O2 class declined, while higher-oxygenated, less toxic classes (O3, O4, O5, O6) increased, suggesting microbial and algal-mediated transformation. Several algal genera exhibited significant correlations with heteroatom composition at different time points, with Ankistrodesmus, Scotinosphaera, and Chloroidium significantly associated with NAFC biodegradation products at the end of the CWTS operating season. These findings suggest that phytoplankton may contribute to NAFC transformation, supporting their contribution to degradation of OSPW components in constructed wetlands.