在河流景观中自我相似性和消失的扩散
Shashank Kumar Anand1, Matteo B Bertagni2, Theodore D Drivas3
1Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544.
概括
景观演变模型揭示了当河流侵蚀占主导地位时,地形学中的普遍性质. 减少土壤扩散导致自我相似的景观,扩散沿着山脊和山谷网络集中.
科学领域:
- 地质形态学 地质形态学
- 景观的演变 景观的演变
- 复杂的系统复杂的系统.
背景情况:
- 复杂的地形通常表现出由河流侵蚀驱动的普遍性质.
- 了解景观演变需要分析不同地形学过程的相互作用.
研究的目的:
- 为了研究极简主义景观演化模型的自我相似行为.
- 分析土壤扩散相对于河流侵蚀在塑造景观中的作用.
主要方法:
- 一维的分析解决方案.
- 两个维度的数值模拟.
- 与现实世界的地形数据进行比较.
主要成果:
- 随着土壤扩散相对于河流侵蚀的减少,观察到的不变行为.
- 与无维的道化指数相比,实现了完全的自我相似性.
- 土壤扩散局限于在消失的极限处的山脊和山谷网络.
结论:
- 景观的自我相似性在主导的河流侵蚀和减少的扩散下出现.
- 局部扩散现象类似于流和非线性系统中的现象.
- 消失扩散极限的地形奇点表明与冲击波的类比.
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