大型山地城市绿地景观动态及驱动力分析

Spatial and Temporal Change of Outsize Mountainous City Landscape Pattern of Urban Green Space

利用1995年和2007年两期TM和ETM遥感影像数据,结合实地调查,研究了重庆市主城区20世纪90年代中期以来绿地景观格局时空变化特点与成因,讨论了不同绿地类型景观区域格局变化。结果表明,(1)重庆成直辖市以来,研究区整体上绿地景观多样性增加,优势度下降,破碎化增加,景观结构变化呈上升趋势。(2)有林地和其他林地比重减轻,景观破碎度增加;高覆盖度草地面积增加明显,破碎化轻微增加,低覆盖草地破碎化降低。(3)绿地景观斑块形状较规则,其中林地景观斑块形状更复杂,属研究区内优势植被类型。(4)研究区内绿地景观同非绿地景观类型间转化明显,表明其受到较强烈的干扰。其中在海拔200 m以下、坡度6°下城市绿地受到干扰最强烈。北碚区和沙坪坝区内绿地景观年变化速率最高。(5)自然灾害(火灾和酸雨)和人为经济、社会活动(包括植被经营和管理、旅游开发和其他人为干扰活动等)是研究时段内绿地景观格局变化主要驱动因素。

By using the landsat TM and ETM images of 1995 and 2007, and through field investigation, this paper studied characteristics and factors of the spatial and temporal change of landscape patterns of urban green space of the main city zone of Chongqing, since mid-90’ s of last century, and discussed different types of landscape pat-terns’ change of the urban green space.The result showed that （1） the landscape diversity index and fragmentation index of the urban green space was increased, the dominance index was declined, the landscape structure changes was raised.（2） The proportion of closed forestland and other forestland was decreased, the fragmentation index was enhanced;the area of closed grassland was increased obviously, its fragmentation index was increased lightly, but low-covered grassland＇s fragmentation index was reduced. （ 3 ） landscape patches shape of the urban green space was more regulated, but the forestland patches shape was more complicated, which was the dominant urban green space types.（4） transferring between the urban green space landscape and other landscape types was obvi-ous that reflected strong disturbance from outside, and the urban green space landscape under the elevation of 200 m and slope of 6＆#176;had the highest disturbance.The Baibei district and Shapingba district had the highest ARG. （5） Natural disasters （fire and acid rain） and man-made economic and social activities （include vegetation man-agement, tourism development and other jamming） were the main drive force of landscape pattern changes of the urban green space.