| 摘要: |
| 城市湿地发挥着越来越关键的作用，其水生态系统的健康评价更是一个重要的过程，有助于我们了解湿地的当前状况并采取相应的保护措施。为探究西藏拉鲁湿地生态系统健康状态及其与水环境因子的关系，于2021年7月（夏季）、10月（秋季）和2022年5月（春季）在拉鲁湿地主要水系进行了浮游植物样品的采集和水环境因子的测定，鉴定浮游植物物种并计算其细胞丰度和生物量，利用浮游植物形态功能群（MBFG）、水质指数（WQI）和浮游植物完整性指数（P-IBI）评价该湿地生态健康状态，分析水质及形态功能群的时空分布特征、P-IBI值与水环境因子的相关性。研究结果表明：（1）基于WQI值评价拉鲁湿地水质总体“良好 ~ 中等”，水体质量存在时空差异：春季优于秋季优于夏季，东部优于西部。（2）基于P-IBI值评价拉鲁湿地三个季节整体的水生态健康状态为“健康 ~ 亚健康”，春季水生态健康状态优于秋季优于夏季，中东部样点普遍优于西南部和东北部。（3）浮游植物生物完整性指数（P-IBI）值与水质指数（WQI）值呈现出显著的正相关关系（P < 0.05），基于P-IBI评价拉鲁湿地水生态健康状态与WQI评价结果接近一致，DO是影响拉鲁湿地水生态健康状态的主要水环境因子（P < 0.05），气温、水量、人类活动和土地利用类型是影响拉鲁湿地水质和水生态健康状态的重要影响因素。（4）春季“Ⅰ”和“Ⅲ”类功能群丰度随拉鲁湿地水生态健康状况的下降而上升，夏季水体生态健康状况与功能群的丰度变化关系不大，秋季“Ⅲ”和“Ⅶ”类功能群丰度的增加与水体生态健康状况的下降有显著关联。 |
| 关键词: 拉鲁湿地 浮游植物生物完整性指数 形态功能群 水质指数 生态健康评价 |
| DOI： |
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| 基金项目:(32070418, 32270473)、青藏高原生物多样性与生态环境保护教育部重点实验室开放课题(KLBE2024010)和2022年中央财政支持地方高校改革发展专项资金(藏财预指[2022]1号)联合资助。 |
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| Assessment of the Ecosystem Health of Alpine Urban Wetlands Based on the Phytoplankton Index of Biotic Integrity |
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Liu Ao, Wang Chen, Han Mengjiao, Peng Qiong, Wei Peipei, An Ruizhi, Ba Sang, Liu Yang
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Laboratory of Wetland and Catchment Ecosystem in Tibetan Plateau, School of Ecology and Environment, Tibet University
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| Abstract: |
| Urban wetlands play an increasingly crucial role, and the health assessment of their ecosystems is an important process that helps us understand the current condition of wetlands and take appropriate protective measures. To explore the ecological health status of the Lhalu Wetland and its relationship with water environmental factors, phytoplankton samples were collected and water environmental factors were measured in the main water systems of Lhalu Wetland in July (summer), October (autumn) 2021, and May (spring) 2022. Phytoplankton species were identified and their cell abundance and biomass were calculated. The ecological health status of the wetland was evaluated using the morphologically -based functional group (MBFG), Water Quality Index (WQI), and Phytoplankton Index of Biotic Integrity (P-IBI). The spatiotemporal distribution characteristics of water quality and morphologically -based functional group, and the correlation between P-IBI values and water environmental factors were analyzed. The research results show: (1) Based on the Water Quality Index (WQI) values, the overall water quality of Lhalu Wetland is evaluated as "good to moderate," with spatial and temporal variations in water quality: spring is superior to autumn, which in turn is superior to summer, and the eastern part is superior to the western part. (2) Based on the Phytoplanktonic Index of Biotic Integrity (P-IBI) values, the overall water ecological health status of Lhalu Wetland across three seasons is evaluated as "health to sub-health," with the spring water ecological health status being superior to autumn, which is superior to summer, and the central-eastern sampling points are generally superior to the south-western and north-eastern parts. (3) The Phytoplanktonic Index of Biotic Integrity (P-IBI) values show a significant positive correlation with the Water Quality Index (WQI) values (P < 0.05), and the evaluation of the water ecological health status of Lhalu Wetland based on P-IBI is closely consistent with the results of WQI evaluation. Dissolved oxygen (DO) is the main water environmental factor affecting the water ecological health status of Lhalu Wetland (P < 0.05), and temperature, water volume, human activities, and land use types are important factors affecting the water quality and water ecological health status of Lhalu Wetland. (4) In spring, the abundance of functional groups "Ⅰ" and "Ⅲ" increases as the water ecological health status of Lhalu Wetland declines. In summer, the ecological health status of the water body has little relationship with the changes in the abundance of functional groups. In autumn, the increase in the abundance of functional groups "Ⅲ" and "Ⅶ" is significantly associated with the decline in the ecological health status of the water body. |
| Key words: Lhalu wetland Phytoplankton Index of Biotic Integrity morphologically -based functional group Water Quality Index Ecological Health Assessment |
