在长江三角洲地区使用随机森林的水动态,中国
Xingna Lin1, Ming Wu1, Xuexin Shao1
1Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China.
The Science of the total environment
|August 26, 2023
概括
在中国长江三角洲地区 (YRDR) 的水度有显著的变化,在河流和池下降,但在一些湖泊上升. 城市化和减少的废水,而不是气候,推动了这些度趋势.
科学领域:
- 环境科学 环境科学
- 遥感 遥感 遥感 遥感
- 水质监测 水质监测
背景情况:
- 度是水生生态系统和生物多样性的关键水质指标.
- 由于经济快速发展,了解长江三角洲地区 (YRDR) 的度动态和驱动因素至关重要.
- 长期的度变化及其与YRDR气候和人类活动的关系尚不清楚.
研究的目的:
- 从1990年到2020年,分析YRDR不同水体的长期度变化.
- 确定影响这些度趋势的主要驱动因素 (气候因素与人类活动).
- 为在YRDR中提供数据,为水生环境保护和恢复战略提供信息.
主要方法:
- 利用Landsat卫星图像,为跨越30年的YRDR (1990-2020) 创建一个全面的度数据集.
- 分析了各种水面的度的空间和时间趋势,包括河流,湖泊和水产养殖池.
- 与区域气候数据,城市化,废水排放以及水建设和生态工程等特定的人类干预相关的度变化.
主要成果:
- 度趋势在水体之间有所不同,主要的长江 (MYR),水产养殖池 (AP) 和其他水域的度显著下降,但中等湖泊 (ML) 和主要的江 (MQR) 的度显著增加.
- 在大湖 (GL) 和小湖 (SL) 中没有观察到显著的度变化.
- 城市化和减少废水排放被确定为度趋势的主要驱动因素,超过气候因素. 在AP的生态工程提高了水的透明度,而三峡大减少了MYR的度. 下游MQR的度增加与季节性水面和回收项目有关.
结论:
- 人类活动,特别是城市化和废水管理,是影响YRDR水系统度的主要因素.
- 具体的干预措施,如生态工程和水建设,对水的透明度产生了局部影响.
- 调查结果强调需要有针对性的管理策略,以应对不同度趋势并保护快速发展地区的水生环境.
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