适应性肉食动物在城市化景观中的食降级
Gabriella R M Leighton1,2, William Froneman3, Laurel E K Serieys4,5,6
1SARChI Chair in Marine Ecology, Department of Zoology and Entomology, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa. gabi.leighton1@gmail.com.
Scientific reports
|December 7, 2023
概括
城市化改变了卡拉卡尔的饮食,人类的影响更大,导致人们依赖人类补贴的猎物在较低的营养水平. 这种利基收缩减少了它们的生态作用,影响了城市生态系统的监管.
科学领域:
- 生态生态学 生态生态学
- 城市生态城市生态学
- 保护生物学 保护生物学
背景情况:
- 城市化改变了野生动物息地和资源的可用性,影响了物种相互作用和热带动态.
- 城市景观中顶级捕食者的丧失可能会导致中食动物角色的改变以及由于人为食物来源的增加而导致的"捕食悖论".
- 了解这些变化对于维持人类主导环境中的生态功能和生物多样性至关重要.
研究的目的:
- 为了研究长期变化,在食用位置,宽度,和重叠的 (Caracal caracal) 响应城市化.
- 通过使用稳定同位素分析,评估人类压力对鱼的食组成和热量状态的影响.
主要方法:
- 稳定同位素分析 (δ13C和δ15N) 在南非开普敦的城市化梯度上采集的毛样本 (n=168).
- 使用人类足迹指数 (HFI) 量化人类压力.
- 对食利基的宽度和重叠的分析,考虑到caracal的人口统计 (性别,年龄).
主要成果:
- 鱼表现出广泛的同位素食利基,表明各种资源的使用.
- 较高的人类足迹指数 (HFI) 与人为补贴的消费增加 (较高的 δ13C) 和转移到较低的热带水平 (较低的 δ15N) 相相关.
- 高度城市化地区的卡拉卡尔显示出更窄的同位素和较低的δ15N值,这表明人们专注于由人类活动补贴的初级消费者.
结论:
- 城市化,加上顶级捕食者的缺失,可以悖论地限制像卡拉卡尔这样的半肉食动物的生态影响.
- 人类补贴推动食转向较低的营养水平,导致利基收缩和潜在的"营养下降".
- 由于掠食者-猎物动态的改变,城市生态系统上下控制的破坏对全球生态系统监管产生了重大影响.
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