摘要
从沉积学的角度分析了锡林郭勒草原沙漠化的地质背景和沙源。锡林郭勒草原直接覆盖在早白垩世二连盆地之上。该盆地各凹陷演化的生命周期完整,同沉积期构造演化结束于基底沉降减缓阶段末,而沉积充填演化结束于湖泊萎缩-平原化阶段,随后一直处于缓慢隆升状态。这样的盆地演化史,导致充填序列上部广泛发育了湖退体系域——厚度巨大且固结程度极低的河流-三角洲砂体。人为因素和气象因素破坏了草原植被,使这些规模巨大的砂体露出地表,造成草原沙漠化基础。显然,地质环境的脆弱性是生态环境脆弱性的决定因素。因此从某种意义上说,锡林郭勒草原沙漠化也是一种地质灾害。如果不进行有效的治理,将会出现大规模沙漠化。这种类型的沙漠化在中国华北、西北和东北乃至世界各地具有普遍性。
This paper studies the causes of grassland desertification from basin analysis and sedimentology perspective. The Xilin Gol Steppe covers above Erlian Basin directly. Various depressions of this basin fea- tures a complete life cycle： Evolution of its synsedimentary structure terminated at the ending period of the basin basement subsidence deceleration stage while sedimentation filling evolution ended in the lake-shrink- ing-plain forming stage, then was in a slow rising state. The evolution processes and results of this basin caused a wide range development of the lakes regressive systems tract at the top of the filling sequence-river and delta sand body with huge thickness and low degree of consolidation. Human factors and meteorological factors destroyed the grassland vegetation, exposing these huge sand bodies to the surface, resulting base of steppe degradation and desertification. Obviously, the vulnerability of the geological environment is the de- termining factor of the vulnerability of the ecological environment in this case. Therefore, desertification in the Xilin Gol Steppe is a kind of geological hazard. Without immediate and effective controls, a large--scale of desertification may occur. This type of desertification is common in North China, North West and North East China. The paper will provide a basis for the treatment of this particular kind of grassland desertifica- tion.
出处
《中国沙漠》
CSCD
北大核心
2018年第1期92-100,共9页
Journal of Desert Research
基金
中国地质调查项目(1212011220096)
关键词
草原退化
土地荒漠化
地质环境脆弱性
锡林郭勒草原
盆地分析
二连盆地
grassland degradation
land desertification
geological environment vulnerability
Xilin GolSteppe
basin snalysis
Erlian Basin
