证据表明,密度依赖于大黄石生态系统不断变化的大型杂食动物的身体组成的影响
Andrea Corradini1,2,3,4, Mark A Haroldson5, Francesca Cagnacci2,4
1Department of Civil, Environmental and Mechanical Engineering (DICAM), University of Trento, Trento, Italy.
Global change biology
|June 1, 2023
概括
灰熊瘦肉体质量随着人口密度的下降而下降,特别是在年轻的雌性中. 然而,身体脂肪仍然稳定,这表明适应性的食肉类缓冲区改变了大黄石生态系统的食物供应.
科学领域:
- 生态生态学 生态生态学
- 哺乳动物的人口统计
- 野生动物群体的动态.
背景情况:
- 密度依赖的过程对人口人口统计学至关重要,但需要长期数据来研究长寿哺乳动物中的密度依赖过程.
- 大黄石生态系统中的灰熊 (Ursus arctos) 面临着环境变化,包括食物来源的减少和人类影响的增加.
- 个人表现指标,如身体组成,是了解人口层面反应的关键.
研究的目的:
- 为了研究灰熊的表现-密度关系,使用身体成分作为个人表现的代理.
- 测试关于人口密度对灰熊瘦体质和体脂的影响的假设.
- 评估杂食在缓冲灰熊对环境和饮食变化的作用.
主要方法:
- 分析了两十年 (2000-2020) 的灰熊体质组成数据集 (瘦体质,百分比体脂).
- 相关的个人绩效指标与大黄石生态系统内的人口密度估计.
- 研究了人口密度和年龄类 (成长中的个体) 如何影响人体组成.
主要成果:
- 个体瘦体质量与人口密度有负面关系,特别是在成长年龄的女性中.
- 身体脂肪水平和积累率基本上不受人口密度或性别的影响.
- 研究结果支持这样一个假设,即食肉有助于灰熊适应不断变化的食物资源.
结论:
- 灰熊瘦肉体质量对人口密度很敏感,突出了密度取决于个人表现的限制.
- 稳定的身体脂肪表明,通过食肉食成功的饮食缓冲,保持能量储备.
- 保护区的长期监测对于理解应对气候变化和人类影响的生态反机制至关重要.
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