30年来象山港海岸带土地开发利用强度时空变化研究

Temporal and spatial variation of land development and utilization intensity in coastal zone of the Xiangshangang Bay

以象山港海岸带为研究区域,利用1985年,1995年,2005年和2015年4期TM遥感影像数据,将土地利用类型分为8大类,通过计算土地利用类型动态度、土地利用转移矩阵、土地利用结构信息熵以及土地开发利用强度综合指数4种指标模型,分析了象山港海岸带1985-2015年土地开发利用的速度、结构、程度以及时空变化。结果表明:(1)1985-2015年象山港海岸带养殖用地及盐田扩张速度最快,动态度最高可达11.97%,建设用地扩张速度次之,但面积增幅最为显著,滩涂缩减速度最大,耕地面积明显减少;(2)30年间土地类型主要转变方向为耕地转为建设用地,其次为林地转变为耕地;(3)信息熵逐时期增加,土地利用结构均质性不断加强,区域发展在逐渐走向成熟;(4)各时期土地利用强度指数变化率均大于零,象山港海岸带土地开发利用强度不断增强。

Taking the coastal zone of Xiangshangang Bay as a study area, based on the information of four TM images of 1985, 1995, 2005 and 2015, the land use types are divided into eight categories. Then, through calculating four kinds of index models ： land-use dynamic index, conversion matrix, land use structure information entropy, and comprehensive index of land development and utilization intensity, researched and analyzed the speed, structure, degree, and the temporal and spatial variation in the land development and utilization of Xiangshangang Bay coastal zone from 1985 to 2015. The results showed that： （ 1 ） From 1985 to 2015, the expansion speed of farming land and salt pan of Xiangshangang Bay coastal zone was the fastest, the highest dynamic degree could up to 11.97 %, construction land expansion ranked the second, and its increase in the area was the most significant; tidal flats reduced by a maximum speed, and the area of farmland decreased obviously. （2） In the past 30 years, the main trend of land type change in Xiangshangang Bay coastal zone was arable land turn into construction land, followed by woodland turn into farmland. （3） Information entropy increased by period, the land use structure heterogeneity constantly strengthened and regional development became gradually mature. （4） The change rate of land use intensity in each period was greater than zero, and the intensity of land development and utilization in Xiangshang Bay coastal zone land is enhanced continuously.