中国南北样带(北部)草地资源特征分析

Grassland resource on Southern and Northern China Transect (northern part).

为研究中国南北样带草地资源的一般特征及其空间分布格局 ,以GIS技术为平台 ,建立了中国南北样带之北部草地资源数据库 ,由此得出样带内草地资源特征及分布概况 ,即样带内草地面积占国土面积的 35 %左右 ,温性草甸草原、温性草原和低地草甸是样带内主要的草地景观类型 ,三者占样带内草地资源总面积的 90 % .总体上评价 ,该地草地资源品质中等偏上 ;5、6级草地所占比例最大 ,占全区草地面积的 5 8% ,2、3、4级占 2 5 % ,其余为 1、7、8级草地 .中国南北样带内草地资源品质、生产量组成的特征显著 ,是其特定草地资源类型组成必然结果 .样带内草地资源空间格局分布明显 ,可分为西中部和中部地带性草原景观区域、东北部和中东部低地草甸草原区域、东南部山地草甸区域和南部暖温性灌草丛草地区域 4个区域 ,这样的分布特征反映了样带生态交错区的特征 .此外 ,样带内的湿地与沙地可能引起的环境作用应给予应有的重视 .

To analyze the general features and patterns of Southern and Northern China Transect (northern part), the authors construct its grassland database by GIS. According to the database,the authors acquire the general information and distribution of the region,which is composed of steppe, temperate steppe, temperate desert steppe, temperate steppe desert, temperate desert, warm temperate herbosa, warm temperate shrub herbosa, tropical shrub herbosa, lowland meadow, mountain meadow, alpine meadow, marshland and improved grassland in the transect,and all of the grassland occupies over 35 percent of the region. Temperate meadow steppe, temperate steppe and lowland meadow are the main grassland type, and their total area is over 90 percent of the transect. In general, the quality of grassland is moderate. For the grassland grade, the area ratios of 5 and 6 are the biggest, 2, 3 and 4 are the middle and the others are 1, 7 and 8. The characteristics of grade and quality are the result of the composition of landscape. The landscape pattern can be distinguished into the steppe situated in the western medium and medium part, the lowland meadow at the north eastern and east medium part, the mountain meadow at the sourth eastern and the warm temperate shrub jerbosa at the south part. The characteristics of landscape reflect the ecotone feature of the transect.