Department of Earth Sciences, ETH Zürich, 8092, Zürich, Switzerland.
Sci Data. 2018 Jul 10;5:180127. doi: 10.1038/sdata.2018.127.
The plan-form structure of the world's river basins contains extensive information regarding tectonic, paleo-geographic and paleo-climate conditions, but interpretation of this structure is complicated by the need to disentangle these processes from the autogenic behavior of fluvial processes. One method of interpreting this structure is by integrating channel length and drainage area as characterized by the scaling relationship between slope and area, resulting in a characteristic length parameter, referred to in recent studies as χ. In this paper, we apply this methodology at a continental scale by calculating χ for the world's river networks. Mapping of χ', a modified version of χ including the influence of precipitation distribution on river discharge and correction of base level for χ' in closed basins, illustrates the geometric structure of global river networks, thus highlighting where tectonics or changing climate have resulted in an apparent disequilibrium of the river channel geometry. Our global χ maps quantify a dynamic view of Earth's river networks and help to identify past and ongoing evolution of Earth's landscape.
世界流域的平面形态结构包含了有关构造、古地理和古气候条件的广泛信息,但由于需要将这些过程与河流过程的自生行为区分开来,因此对这种结构的解释变得复杂。解释这种结构的一种方法是通过整合渠道长度和排水面积,其特征是斜率和面积之间的比例关系,从而产生一个特征长度参数,在最近的研究中称为 χ。在本文中,我们通过计算世界河流网络的 χ 值,在大陆尺度上应用了这种方法。 χ'的映射, χ 的一个修改版本,包括降水分布对河流流量的影响,以及 χ'在封闭流域中的基准面校正,说明了全球河流网络的几何结构,从而突出了构造或气候变化如何导致河道几何形状明显失衡的地方。我们的全球 χ 图量化了地球河流网络的动态视图,并有助于识别地球景观的过去和正在进行的演变。