由于大气中的沉积,西北太平洋的丰度增加
Tae-Wook Kim1, Kitack Lee, Raymond G Najjar
1School of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Science (New York, N.Y.)
|September 24, 2011
概括
大气沉积造成的污染,在西北太平洋增加了 (N) 超过 (P). 这种转变使海洋生态系统从受限变为受限.
科学领域:
- 海洋化学 海洋化学
- 海洋学 海洋学 海洋学
- 环境科学环境科学
背景情况:
- 自1980年以来,西北太平洋的边缘海洋显示出酸盐 (N) 与 (P) 的相对丰度增加.
- 这个地区位于亚洲工业化大陆的下游,这表明人类的影响.
研究的目的:
- 调查西北太平洋边缘海域中气可用性增加的驱动因素.
- 为了确定改变营养比例对海洋生态系统限制的影响.
主要方法:
- 对海水中营养物质度 (酸盐和) 的历史数据进行分析.
- 大气中沉积估计值与观察到的度之间的相关性分析.
- 在特定区域评估河流输入量.
主要成果:
- 自1980年以来,N比P的显著增加已被观察到.
- 大气中沉积被确定为增加N可用性的主要驱动因素,显示出高时间相关性 (r = 0.74到0.88).
- 在某些地区,河流的输入也是一个重要的因素,有助于转移.
结论:
- 增加的的可用性,主要来自大气沉积和河流输入,已经改变了西北太平洋边缘海域的营养体质量.
- 广大地区已经从限的生态系统转变为限的生态系统.
- 这些变化对海洋生物地质化学循环和生态系统运行有重大影响.
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