食物网属性的尺度不变性
G Sugihara1, K Schoenly, A Trombla
1Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093.
概括
即使数据分辨率降低,食物网的特性也保持一致. 这一发现支持了不同数据尺度的食物网分析的可靠性.
科学领域:
- 生态生态学 生态生态学
- 理论生态学理论生态学
- 食物网络动力学 食物网络动力学
背景情况:
- 食物网理论依赖于详细的生态数据.
- 批评者质疑食物网属性是否对数据分辨率 (热带聚合) 敏感.
- 了解强度是验证食物网模型的关键.
研究的目的:
- 评估五种常见的食物网属性的稳定性.
- 为了确定这些属性是否保持不变,尽管数据分辨率有所变化.
- 为了解决有关食物网络指标对食物聚合的敏感性的担忧.
主要方法:
- 分析了60个无脊椎动物主导的社区食物网.
- 系统地聚合热带分组以减少数据分辨率.
- 检查了五个关键的食物网统计数据:链条长度,捕食者/猎物比率,顶部/中间/底部物种的比例和刚性电路.
主要成果:
- 当数据分辨率降低高达50%时,五个常见的食物网属性表现出惊人的稳定性.
- 除了一个外,所有检查的属性都在聚合的食物网中得到证实.
- 发现食品网络统计数据是可扩展的,在广泛的数据分辨率中保持不变.
结论:
- 观察到的食物网属性在2.0的因子内对食物聚合具有强度.
- 这些发现解决了关于数据解析灵敏性的食物网理论的常见批评.
- 经过验证的食物网统计数据可以可靠地用于比较不同数据分辨率的生态系统.
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