Channel network simulation models compared with data from the Ashley River, New Zealand
Channel network simulation models compared with data from the Ashley River, New Zealand
复制标题
航道网络模拟模型与新西兰阿什利河数据的比较
DOI：
10.1029/1999wr900245
复制
发表时间：
1999
影响因子：
5.4
通讯作者：
M. Duncan
中科院分区：
文献类型：
--
作者：
R. Ibbitt;G. Willgoose;M. Duncan
本文比较了两种河道网络模拟模型模拟新西兰南岛南阿尔卑斯山麓阿什利河河道网络特性的能力。选择盆地是因为它包含一个大尺度的地形特征，一个中央山脊，模拟它将提供一个衡量每个模型处理空间不均匀性的能力。评估的两个模型是最佳渠道网络（OCN）模型和流域演变模型（SIBERIA）流域演变模型。评估了这些模型复制观测到的地貌统计数据和关系的能力。这些模型还相互比较，以评估它们模拟观测到的地貌的相对适用性。使用单值测量集水区收敛、高程积分和网络能量消耗，以及宽度函数、累积面积图斜率和流域地形高程曲线图，对模型性能进行了评估。不同的强迫的影响进行了检查。基本强迫是假定盆地的气候、地质和构造特性在空间和时间上都不变的强迫。基本强迫的第一个变体着眼于当在具有空间均匀的地质和构造特性的盆地上降雨存在永久空间梯度时会发生什么。第二个变量考虑了恒定的，空间上均匀的降雨量对盆地的影响，其中空间变化的构造隆起正在发生。当忽略空间不均匀的构造强迫时，两种模型都不能充分模拟观测到的地貌。当模拟几十公里尺度的空间非均匀构造效应时，西伯利亚的表现更令人满意。不均匀降雨的影响被认为是小的两个模型。当能量消耗计算与流动路径的几何长度一致时，通过单值测量测量的OCN的性能显著改善。
This paper compares the ability of two channel network simulation models to simulate the channel network properties of the Ashley River in the foothills of the Southern Alps of the South Island of New Zealand. The basin was chosen because it contains a large‐scale topographic feature, a central ridge, the simulation of which would provide a measure of each model's ability to handle spatial nonuniformities. The two models assessed were the optimal channel network (OCN) model and a catchment evolution model (SIBERIA) catchment evolution model. The ability of these models to replicate observed geomorphic statistics and relationships was assessed. The models were also compared against each other to assess their relative suitability for simulating the observed geomorphology. Model performance was gauged using the single‐valued measures of catchment convergence, hypsometric integral, and energy expenditure by the network; and plots of the width function, the slope of the cumulative area diagram, and the hypsometric curve of basin topography. The effects of different forcings were examined. The basic forcing was one in which the climate and the geological and tectonic properties of the basin were assumed to be unchanging in both space and time. The first variant on the basic forcing looked at what happens when there is a permanent spatial gradient in the rainfall over a basin with spatially uniform geological and tectonic properties. The second variant considered the effects of constant, spatially uniform rainfall on a basin in which spatially variable tectonic uplift is occurring. Neither model adequately simulated the observed geomorphology when the spatially nonuniform tectonic forcing was ignored. When spatially nonuniform tectonic effects at length scales of tens of kilometers were simulated, SIBERIA performed more satisfactorily. The effect of nonuniform rainfall was found to be small for both models. The performance of the OCN as gauged by single‐valued measures improved markedly when energy expenditure calculations were consistent with the geometric length of flow paths.