在海洋海生态系统中,优化,渔业和消费者资源动态
1National Center for Ecological Analysis and Synthesis, Santa Barbara, CA 93101, USA.
Science (New York, N.Y.)
|August 28, 1999
概括
营养丰富增加了植物浮游生物,而渔业减少了海洋生态系统中的食草动物. 然而,这些影响削弱了食物网,尽管存在变化,但仍显示出普遍的变化模式.
科学领域:
- 海洋生态海洋生态学
- 生态系统动力学 生态系统动力学
- 食物网络结构 食物网络结构
背景情况:
- 海洋生态系统面临着人类活动造成的全球变化,如营养污染和渔业.
- 这些活动显著改变了资源的可用性和海洋食物网的结构.
研究的目的:
- 调查营养丰富和消费者压力对海洋生态系统的广泛影响.
- 分析这些因素如何影响全球的食物网络结构和社区动态.
主要方法:
- 进行了47个海洋中宇宙实验的元分析,这些实验操纵了营养素和消费者.
- 分析了来自20个自然海洋系统的时间序列数据,包括营养素,浮游生物和鱼群.
主要成果:
- 营养丰富通常会增加浮游植物生物质.
- 肉食动物的存在通常会抑制草食动物的生物量.
- 通过类食物网观察到资源和消费者效应的减弱,这表明植物浮游生物和草食动物的合力较弱.
结论:
- 尽管环境具有显著的变化,但人为导致的资源可用性和消费人口的变化导致了可预测的社区层面的海洋鱼生态系统的变化.
- 了解这些一般模式对于海洋保护和管理至关重要.
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