基于Shannon多样性t检验法的土地利用景观分区研究*——以重庆市永川区为例

STUDY ON LANDSCAPE ZONING OF LAND USE BASED ON SHANNON DIVERSITY T-TEST METHOD*——A CASE STUDY OF YONGCHUAN DISTINCT OF CHONGQING

关键词:  土地利用Shannon多样性指数t检验法景观指数景观格局景观分区

Key words:  land use  Shannon diversity t test method  landscape index  landscape pattern  landscape zoning

摘要:

［目的］根据区域景观差异性进行土地利用景观分区，以期为土地利用分区和土地利用政策制定提供理论依据。［方法］文章以重庆市永川区为研究对象，以2005年和2015年的遥感影像为基础数据源，借助RS和GIS技术对2期的影像进行解译，得到永川区2期土地利用类型图； 利用景观指数法与Shannon 多样性t值检验法进行全区土地利用景观格局变化的数量结构和各乡镇土地利用景观变化显著性分区研究。［结果］（1）从类别层级分析， 2005—2015年间，建设用地、林地表现为增加趋势，耕地、草地、未利用地表现为减小趋势。耕地为永川区的优势景观类型（2005年和2015年各占土地总面积5446%、4976%），耕地、建设用地、林地受人为干扰强烈且趋于规则化。（2）从景观层级分析，蔓延度指数增大，Shannon多样性指数、Shannon均匀度指数、散布与并列指数、景观形状指数均减小。（3）利用Shannon多样性t检验法对永川区进行土地利用景观格局分区。景观变化极显著区，主要位于主城区及其周围地区，城市化现象显著，人为活动影响大； 景观变化显著区，该区土地利用程度较弱， 2005—2015年林地和水域面积增大，耕地面积减小； 景观变化不明显区，该区主要分布在远离中心城区，经济欠发达，景观格局变化不明显，人为活动干扰不明显。［结论］永川区各乡镇的土地利用景观格局变化差异性，表明在自然因素稳定的条件下，今后应因地制宜地加强人为因素的调控，保证各乡镇土地利用景观格局稳定协调发展。

Abstract:

According to the difference of regional landscape , the landscape zoning of land use is carryied out in order to provide a theoretical basis for the zoning of land use and the formulation of land use policies. Taking Yongchuan district of Chongqing as the research object, based on the remote sensing images in 2005 and 2015 as the basic data source, the two stage image was interpreted by RS and GIS technology, and the land use type map of Yongchuan district was obtained. The quantitative structure of the landscape pattern of land use and the significant zoning of districts and counties were comprehensively studied by using the method of landscape index method and Shannon diversity t test. The results were showed as below. First, for the classification level analysis, during 2005 to 2015, construction land and forest land showed an increasing trend, while cultivated land, grassland and unused land showed a decreasing trend. Cultivated land was the dominant landscape type in Yongchuan district (54.46% and 49.76% of the total land area in 2005 and 2015 respectively). Arable land, construction land, and forest land were strongly disturbed by man made and tend to be regularized. Second, for the landscape scale analysis, the spread index increased, and the Shannon diversity index, the Shannon uniformity index, the spread and the side by side index, and the landscape shape index decreased. Finally, the Shannon diversity t test was used to divide the landscape pattern of land use in Yongchuan district. The most significant landscape change areas were mainly located in the main urban area and its surrounding areas, and the urbanization phenomenon was significant and the human activities had a great influence on them. The degree of land use in the areas with significant landscape changes was relatively weak, during 2005 to 2015, the area of woodland and water area increased and the area of cultivated land decreased. The area which its landscape change was not obvious was mainly located far from the central urban area, the economy was underdeveloped, and the landscape pattern changes and the human disturbance were not obvious. The variation of landscape pattern of land use in different towns in Yongchuan district shows that under the condition of the stable natural factors, the adjustment of human factors should be strengthened according to local conditions to ensure the stable and coordinated development of landscape pattern of land use in different towns in the future.