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湿地水质模式和美国大陆的人为压力协会
Anett S Trebitz1, Alan T Herlihy2
1U.S. Environmental Protection Agency, Office of Research and Development, Duluth MN 55804.
概括
人类活动显著影响内陆湿地水质,增加离子强度和营养素,即使在孤立的湿地类型中. 自然因素,而不是人类的压力,在某些地区推动了酸性pH和高溶解有机碳.
科学领域:
- 环境科学 环境科学
- 生态生态学 生态生态学
- 水文学的水文学
背景情况:
- 人类对湖泊和溪流水质量的影响得到了充分的证据.
- 湿地水质及其与人类压力的关系不太清楚.
- 内陆湿地在生态系统健康和水调节方面发挥着至关重要的作用.
研究的目的:
- 描述美国内陆湿地的水质.
- 评估水质和人为压力之间的关系,在相邻的和采集区的尺度.
- 确定水质变化的来源,包括自然和人为因素.
主要方法:
- 利用了2016年国家湿地状况评估 (NWCA) 的数据,涉及525个内陆湿地.
- 测量了水质参数,包括pH值,离子强度 (化物,硫酸盐,导电性),营养物质 (总N和P),度,叶绿素和溶解有机碳 (DOC).
- 使用现场检查清单 (相邻规模) 和陆地覆盖数据 (捕捞规模) 评估人为压力.
主要成果:
- 水质差异很大,离子强度,营养素,pH和DOC范围很广.
- 邻近的压力和采集范围的压力都与较高的离子强度指标 (化物,硫酸盐) 相相关.
- 捕获量级压力与营养物质的增加有关,但不是浮游生物;酸性pH和高DOC与低压位相关,这表明自然来源.
结论:
- 人类造成的压力,特别是来自农业和城市土地利用,通过增加离子强度和营养水平,影响内陆湿地水质.
- 即使是没有流入溪流的湿地,也显示出离子强度和营养素增加,随着更大的水域规模的人类土地利用.
- 自然因素,如地质和气候,似乎是某些湿地类型和地区酸性pH和高溶解有机碳的主要驱动因素.
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