农业投入修改了人类修改的景观中顶级捕食者的热带和基本能量来源
André C Pereira1,2, Christy J Mancuso3, Seth D Newsome3
1Departamento de Zoología, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, Brazil.
概括
息地碎片化影响了食物网. 在巴西,鱼 (Caiman crocodilus) 通过利用多种食物来源适应农业区,这表明景观管理可以支持生物多样性.
科学领域:
- 生态与保护生物学 生态与保护生物学
- 食物网络动力学 食物网络动力学
- 景观生态学 景观生态学
背景情况:
- 土地利用转换和息地碎片化破坏生态系统功能,改变食物网结构,导致生物多样性丧失.
- 巴西中部的阿拉瓜亚河泛滥平原是一个充满活力的景观,正在经历重大修改.
- 眼镜鱼 (Caiman crocodilus) 作为一个指标物种,用于评估生态系统的健康状况,因为它扮演了顶级捕食者的角色.
研究的目的:
- 调查景观修改对凯曼鱼 (Caiman crocodilus) 使用的食物网结构和初级生产力来源的影响.
- 根据息地属性,评估鱼同位素宽度的空间和时间变化.
- 确定自然和人为区域是否支持不同初级生产者的食物网.
主要方法:
- 碳 (δ13C) 和 (δ15N) 同位素值被测量在三个有不同转换率的鱼组织中.
- 层次贝叶斯模型被用来分析同位素的宽度,包括息地使用,性别,身体大小和景观组成/配置.
- 分析了必需氨基酸 δ13C 值,以追踪自然与人为区域中的水生食物网的主要生产力来源.
主要成果:
- 居住在农业地区的鱼与自然息地相比,其同位素幅显著更大.
- 这种扩大的利基很可能反映了陆地资源,特别是C4植物,被纳入因地形变化的海的饮食中.
- 自然和人为息地之间的必需氨基酸 δ13C 值的不同模式证实了初级能源的差异.
结论:
- 凯曼鱼表现出适应能力,能够通过利用自然和农业能源,在异质的景观中持续存在.
- 这些发现强调了有效的景观管理战略的潜力,这些战略将自然和人为区域整合起来,以支持生物多样性.
- 这项研究强调了了解食物网对土地利用变化的反应对于热带洪水平原的保护工作的重要性.
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