中国地貌区划系统——以自然保护区体系建设为目标

地貌类型是重要的自然地理特征,是影响区域生物多样性空间格局变化的重要因子。地貌研究能使人们深入认识地理环境特点,有利于完善对区域自然环境和地域分异规律的认识,同时对生物地理区划和区域自然保护研究也具有很好的参考价值。采用"自上而下"的区域分割和"自下而上"的区域合并的区划方式,以中国地形DEM作为基础,使用GIS10.0对其进行高程重分类、坡度分析等量化分析,并结合现有气候区划、自然地理区划和地貌类型等资料,对中国地貌格局进行了分析。在考虑生物多样性保护过程中以地貌为主体的地理单元差异性基础上,根据分析结果,提出了以区域自然保护区体系构建为目标的中国地貌区划系统,该地貌区划系统包括了东部季风淋蚀地貌大区、西北干燥风蚀地貌大区、青藏高原高寒冻蚀地貌大区、南海诸岛地貌大区等4个地貌大区,大兴安岭、小兴安岭和内蒙古高原等40个地貌地区,完达山、老爷岭和张广才岭等127个地貌亚地区,以及473个地貌区。其地貌区划方案科学构建了区划等级系统,体现了中国地貌类型的基本特征和分布格局,其中地貌大区基本反映了中国大的地貌格局,地貌地区基本反映了高原、山地、平原等地貌特征的水平分异,地貌亚地区和地貌区基本反映了区域地貌特征。中国地貌区划系统为自然保护区体系构建提供了参考和依据,而且区划界线准确,便于使用。

Geomorphologic regionalization of China aimed at construction of nature reserve system

Given that it is an important natural geographic feature, geomorphic type is an important factor that results in a change in spatial pattern of regional biodiversity. The study of natural landforms can promote greater understanding of geographic environment characteristics. At the same time, the present study has great reference value in the investigation of natural geographic divisions and regional nature conservation research. It is also conducive to improvement of the understanding of the natural environment and differentiation in a region. In the present study, the landscape pattern of China was analysed using a qualitative and quantitative approach, based on data of the terrain digital elevation model. We then determined a geomorphologic regionalization system for the country. In the course of analysis, relative consistency, completeness and hierarchical division were the guiding principles. Further, the methods of "top down" regional segmentation and "bottom up" regional merger were used. Through a quantitative analysis using GIS10.0 software, we obtained the outcomes of reclassification of elevation, slope analysis, and others. According to the result and the data of climate regionalization, natural geographic regionalization, geomorphic types and others, the geomorphologic regionalization system of the country is proposed, which is aimed at construction of a regional nature reserve system and biodiversity protection. This geomorphologic regionalization system included four geomorphologic zones (the eastern monsoon rain erosion geomorphologic zone, the northwest dry wind erosion geomorphologic zone, Qinghai-Tibet Plateau high frost weathering geomorphologic zone, and the South China sea islands geomorphic zone), 40 geomorphologic areas (for example the Da Xing'an Mountains, Inner Mongolia Plateau, and the Xiao Xing'an Mountains), 127 geomorphologic subareas (for example Wandashan, Laoyeling, and Zhangguangcailing), and 473 geomorphologic regions. The division level of the geomorphologic regionalization system was scientifically constructed, and reflects the basic features of geomorphic distribution. The geomorphologic zone reflects the diverse landscape pattern of China. The geomorphologic area reflects the horizontal differentiation features of plateaus, mountains, and plains. The geomorphologic subarea and geomorphologic region indicate regional geomorphic characteristics. It is difficult to use mathematical methods to directly determine morphological differences, on account of the complexity of natural geographic features. However, the results of quantitative analysis can be used as a reference for qualitative analysis. The features of geomorphologic regionalization system are listed as follows: (1) The South China Sea, which has unique climate characteristics and geological geomorphologic features, was distinguished as an independent zone. (2) Given the intent of constructing the nature reserve system, there is a substantial difference with other geomorphologic regionalization. Further, our regionalization system appears to be more scientific and accurate, as well as having greater definition. Thus, the system can be used as the basis of natural conservation geographic regionalization, and provides a reference and foundation for the construction of a nature reserve system. (3) Our system is easier to understand and master, using the usual naming convention in the geomorphologic system. (4) Large quantities of topographic data and an advanced geographic information technology were used to ensure the objectivity and scientific integrity of the results.