在一个高度入侵的河口中,入侵速度加速
1A. N. Cohen, San Francisco Estuary Institute, 1325 South 46 Street, Richmond, CA 94804, USA. J. T. Carlton, Maritime Studies Program, Williams College-Mystic Seaport, Post Office Box 6000, Mystic, CT 06355, USA.
Science (New York, N.Y.)
|January 28, 1998
概括
生物入侵对环境和经济构成重大威胁. 旧金山湾和三角洲可能是世界上最常被入侵的河口,原因是众多的异国物种和加速的入侵率.
科学领域:
- 生态生态学 生态生态学
- 环境科学 环境科学
- 保护生物学 保护生物学
背景情况:
- 生物入侵是一个关键的全球性挑战,影响着全球生态系统和经济.
- 旧金山湾和三角洲的生态系统是研究入侵动态的焦点.
研究的目的:
- 分析旧金山湾和三角洲生物入侵的程度和速度.
- 识别导致这条河口入侵水平高的潜在驱动因素.
主要方法:
- 在息地之间对物种组成,丰度和生物量进行生态评估.
- 分析历史和当前的入侵趋势.
- 评估潜在的促成因素,如运输载体和息地破坏.
主要成果:
- 有相当数量的异国物种已经建立起来,按物种,个体数和生物量统治了众多息地.
- 新入侵的速度很高,似乎正在加速.
- 旧金山湾和三角洲表现出潜在的全球最被入侵的河口的特点.
结论:
- 旧金山湾和三角洲面临严重的生物入侵,具有重大的生态和经济影响.
- 导致这种高入侵水平的因素包括多样化的运输载体,不那么多样化的本地物种池和广泛的息地扰乱.
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