三江源地区水系形成机理、形态特征和演化趋势研究

River systems represent a common example of dynamic systems displaying spatio-temporal variation. These systems play an indispensable role in regard to human daily life. River systems appear to be disorderly, but in fact display intrinsic order. They are influenced by, and interact with climate, geomorphology, geology, vegetation and even the activities of human beings and animals. .The Sanjiangyuan area in west China, which is undergoing continuous surface uplift, has many examples of rivers within a complex environment, and so represents an appropriate study area. The research project proposed here is focused on the mechanisms of river system evolution and the character of river system morphology in the Sanjiangyuan area. Basic information concerning the Sanjiangyuan river system, obtained from the river network with high precision, delineates a river system database. A complete dynamic model of river system evolution will be developed based on this river system database, through a combination of field observation, big data and statistical analysis, mathematical modeling and model testing. This river system evolution model allows representation of the past state (formation), the current state (morphology) and the future state (evolution), thus describing the river system as it evolves from the beginning to the future. Both general and special morphological characteristics of the Sanjiangyuan river system will be recognized in the course of research, the latter of which may be caused by the special geomorphology of the area. The correlation between the river system and other influencing factors, such as vegetation and climate, will be quantified. The study of the evolution mechanism and morphological character of the Sanjiangyuan area provides a basis for the guidance in regard to societal stability, as well as development within the middle and lower river basins farther downstream.

水系是自然界中与人类日常生活栖息相关的随着时空变化的动态系统之一，虽然错综复杂但却井然有序。水系受气候、地质地貌和植被覆盖以及动物和人类活动等因素的影响从而不断改变自己的结构形态和生态体系。.位于中国西部不断抬升的三江源地区，水系丰富，具有复杂的地貌和气候，有利于对河流发育进行调查研究。以三江源地区为研究区域，建立该地区水系基本信息数据库，采用实地考察、大数据、数值模拟和模型试验等方法和手段，对该地区水系的发育初期（形成）、现状（形态特征）和未来演化趋势建立一个完整的水系演化动态系统。寻找水系发育演化和外在影响因素之间的相关关系，确定水系发展的控制因素。探讨三江源地区水系所具有的共性和特性，揭示该地区水系的形成机理和演化机制等科学问题。尝试采用人工模拟的方法来模拟三江源水系的现状和展示未来演化趋势，为三江源地区水资源开发和生态保护提供科学依据和指导，从而保证中下游社会经济稳定和发展。

三江源地区作为独一无二的三条河流的源区，具有自己独特的自然、生态和人文环境，该区域具有重大的科学研究价值和开发价值，如何正确的认识、合理的使用和有效的保护三江源地区是一项巨大的工程。本项目从三江源地区水系入手，采用大数据、野外科考、建立模型、统计分析等多种手段对三江源地区的水系及其相关影响因素开展研究。.主要研究内容包括：.1）提取了三江源地区的流域水系河网，通过对其河网的特征分析，得到了三江源水系演化服从全球水系几何增长一般特性的结论；建立了三江源地区地貌、气候、植被和生物等自然条件和居民、经济等人文社会条件的数据库，为三江源地区的各类研究和资源保护提供科学的数据支持；.2）基于对三江源地区的各种地貌过程诸如河道侵蚀、边坡滑坡、断壁瀑布以及地壳运动等的探索和模拟，建立了基于水沙输移的基岩侵蚀MRSAA模型，以及与各个地貌过程对应的子模型块；构建了将各个地貌演变子过程集成一体的具有流域尺度的地貌动态演化模型系统，揭示了水系的形成机理，模拟了流域的未来演化，推动了地貌演化模型（LEM）研究学科的发展；.3）建立了三江源地区植被演化模型以及放牧活动影响模型，揭示了三江源地区植被和畜牧业对气候的相互影响，为三江源地区水资源开发和生态保护提供科学依据和指导。