上向下与下向上:放牧和上升模式改变了温暖气温系统中初级生产率的模式
Abby R Gilson1, Christopher McQuaid1
1Department of Zoology and Entomology, Rhodes University, Grahamstown, South Africa.
Ecology
|October 3, 2023
概括
上游增强了沿海系统的初级生产,但上下放牧控制仍然很重要. 这项研究揭示了上游和放牧如何相互作用来塑造海洋社区,影响藻类和无脊椎动物.
科学领域:
- 海洋生态海洋生态学
- 海洋学 海洋学 海洋学
- 社区生态学 社区生态学
背景情况:
- 社区结构是物理和生物相互作用的结果,受到环境梯度的影响.
- 预计自上而下的控制强度将随着初级生产率的变化而变化,而上游影响沿海系统的资源可用性.
- 海洋群落上升和放牧压力之间的相互作用尚未得到充分理解,尤其是在温暖的气候地区.
研究的目的:
- 研究放牧压力和上流对状无脊椎动物和宏藻群体的影响.
- 了解在温暖的海洋系统中上游和放牧之间的相互作用.
- 为了确定从上游的营养补贴如何影响自上而下的控制动态.
主要方法:
- 在不同的上游系统中进行了现场除草动物排除实验.
- 在温暖气温的沿海海洋系统中重复实验.
- 评估的状无脊椎动物覆盖和大藻生物量.
主要成果:
- 在上游地区藻类生物量较高,而在非上游地区被排除在外的牧草动物时,性无脊椎动物覆盖率较低.
- 当放牧者被排除在外时,宏观藻类覆盖在上游地点更高,继承起着重要作用.
- 放牧影响在上游地区更为明显,特别是在冬季,在早期的继承阶段放牧的趋势更大.
结论:
- 来自上游的自下而上的营养效应不会在这个系统中取代自上而下的控制,但会影响无脊椎动物群体.
- 上游影响藻类生产和草食之间的平衡,对太空竞争产生影响.
- 海洋温度上升可能会通过促进草食动物的生长和新陈代谢来加强上升区域的自上而下的控制.
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