人为动力泥沙灾害类型及其特征初步研究

人为动力泥沙灾害是人类活动无意地导致地表物质侵蚀、输移、沉积过程中的渐近或超临界现象 ,它具有独特的社会学及灾害学属性。按人为驱动力形式、灾害所在地貌部位、灾害的表现形式及具体灾害现象 ,人为动力泥沙灾害系列可划分为 :流域水系、沟道坡面、河道及平原河口海岸四个泥沙灾害类 ;各灾害类包括侵蚀型、搬运型、堆积型、复杂型及关联型五种泥沙灾害型 ;共 54个灾害种。这是一种比较综合、系统的人为动力泥沙灾害类型划分。从流水地貌、泥沙运动及灾害学相结合出发 ,人为动力泥沙灾害具有以下特征 :1地理地带基础上的加剧性特征 ;2人文环境影响下的渐变性与急变性特征 ;3盲目性驱动下的无序性特征 ;4复杂性和非线性特征等。人文环境的变化是人为动力泥沙灾害产生的主要原因。只有加强管理力度 ,提高人民的环境保护意识 ,才能控制人为泥沙灾害的发生。

A Preliminary Study on Types and Characters of Man-induced Sediment Disaster

The man induced sediment disaster is identified as a kind of processes for land surface material to advance gradually or to surpass threshold erosion, transportation and accumulation by man's activities. It possesses special attributes in sociology and disaster science. In accordance with the form of man's activities, geomorphologic lacation behavior and particular, the man induced sediment disaster can be divided into 4 types: the drainage network, slope and gully, channel and plain estuary coastline. Each type includes 5 subtypes, e.g. erosion, transportation, accumulation, complexity and correlation. There are more than 54 kinds of man made sediment disasters, for example, destroying forest for farming, constructing highway and road, too much small and middle coal mining, cave dwelling, discarded earth and stone into channel sand gullies, excavated beyond normal limit of sand in river bed, desertification of cultivated lands, soil salinization, much more sedimentation above a dam and erosion below one after reservoir building, transporting water from one drainage basin to another one, etc..According to combination of man's activities, geomorphology, and sediment mechanics with disaster science, the man induced sediment disaster is characterized by such properties as (1) accelerating tendency with geographical zonation, (2) sharply changing with human environment alvibration, (3) non order under blind action without special technically training, and (4) complexity and non linear figure, etc. One of the important reasons lead to man induced sediment disaster is the human environment vibration. If it is stable and people have high training, the man induced sediment disaster should be reduced, and vise versa. Therefore, it could be controlled only as through strengthening sediment management, correctly executing the water soil conservation law, and rising people's understanding of environmental protection by education.