摘 要

本文基于遥感及GIS对汉江中下游流域1998年、2003年、2008年、2013年、2018年区域遥感影像进行解译，利用土地利用动态度、空间转移矩阵及景观指数对近20年来流域景观格局时空特征进行变化分析和成因归纳，结果表明：① 汉江中下游流域主要景观类型是耕地，1998年最高占流域总面积比例约55%，近20年来耕地景观向建筑用地景观的转化是城镇用地迅速扩张的主要原因。在1998年-2008年的十年中由于耕地、部分林地、草地的转化，水域及水利设施用地景观面积有所上升，后十年时间面积保持稳定。林地、草地在2003年退耕还林政策实施后与耕地间的转化开始活跃起来，就结果来看，林地、草地及其他用地景观面积变化幅度较小，景观保存程度相对完整。②景观水平上，1998年-2018年的20年间流域斑块数量及斑块密度整体呈现上升的趋势，边缘密度、香农均匀度和香农多样性指数保持增长，景观格局整体趋于破碎化、多样化、异质景观类型间交错分布的模式。景观类型上，耕地景观斑块数量不同年份波动情况较多，但整体表现为上升的趋势，林地、水域、建筑用地斑块数量显著增多，边界密度升高、复杂程度增强，草地及其他用地整体变动较小。③在1998年-2018年的20年中流域景观格局演变驱动因素以人口、经济、政策等人类因素为主导，水汽含量、温度等气候因素起次要的驱动作用。④近年山地地区耕地过度开垦问题较严重，山区生态脆弱区域亟需推行生态保护措施。

关键词：景观格局演变；驱动因素；汉江中下游；空间转移矩阵；景观指数

Abstract

Based on remote sensing and GIS, this paper interprets the regional remote sensing images of the middle and lower reaches of the Han River in 1998, 2003, 2008, 2013 and 2018, and analyzes the spatial and temporal characteristics of the landscape pattern of the river basin in recent 20 years by using land use dynamic degree, spatial transfer matrix and landscape index. The results show that: ① The main landscape type in the middle and lower reaches of Hanjiang River Basin is cultivated land, which accounted for 55% of the total area of the basin in 1998. In recent 20 years, the main reason for the rapid expansion of urban land is the transformation of cultivated land landscape to building land landscape. In the ten years from 1998 to 2008, due to the transformation of cultivated land, part of forest land and grassland, the landscape area of water area and water conservancy facilities increased, and the area remained stable in the last ten years. After the implementation of the policy of returning farmland to forest in 2003, the conversion between forest land and grassland and cultivated land began to be active. As a result, the change range of landscape area of forest land, grassland and other land is relatively small, and the degree of landscape preservation is relatively complete. ② At the landscape level, the number and density of patches in the basin showed an overall upward trend in the 20 years from 1998 to 2018. The edge density, Shannon evenness and Shannon diversity index kept growing, and the landscape pattern as a whole tended to be fragmented, diversified and staggered distribution among different landscape types. In terms of landscape type, the number of landscape patches of cultivated land fluctuates more in different years, but the overall trend is upward. The number of patches of forest land, water area and construction land increases significantly, the boundary density increases, the complexity increases, and the overall change of grassland and other land is small. ③ In the 20 years from 1998 to 2018, human factors such as population, economy, policy and so on are the driving factors of landscape pattern evolution, while climate factors such as water vapor content and temperature play a secondary role. ④ In recent years, the problem of over reclamation of cultivated land in mountainous areas is serious, and ecological protection measures are urgently needed in the ecologically fragile areas of mountainous areas.

Key Words：landscape pattern change；driving factors；middle and lower reaches of Hanjiang River；landscape transfer matrix；landscape index

目 录

摘要I

AbstractII

第1章 绪论1

1.1 研究背景和意义1

1.2 国内外研究现状2

1.3 主要研究内容3

第2章 研究区域及研究方法4

2.1 研究区域概况4

2.2 数据来源介绍5

2.3 研究方法说明6

2.3.1 土地利用分类6

2.3.2 空间转移矩阵6

2.3.3 景观指数分析7

第3章 景观格局演变特征分析8

3.1 土地利用类型变化8

3.2 景观类型空间转移11

3.3 景观指数变化分析15

3.3.1 景观水平指数分析15

3.3.2 景观类型指数分析19

第4章 景观格局演变驱动因素分析24

4.1 自然因素分析25

4.2 人类因素分析26

4.2.1 经济发展27

4.2.2 人口增长27

4.3.3 政府政策28

第5章 结论与讨论30

参考文献32

致谢35

1. 绪论

1.1 研究背景和意义

进入21世纪以来，中国经济体系进入高速发展时期，农业农村现代化和乡村乡镇城市化成为大势所趋，城市化的进程正如火如荼。同时，城市化的推进也将诸多潜藏的人口与环境的矛盾带到了社会面前。伴随着城市化的快速发展，汉江中下游流域人口呈现向城镇不断集中的趋势，以耕地为代表的用地类型面积持续下降、分裂程度加深^[1]。流域景观格局在社会处于高速发展模式的现状下发生着剧烈而深刻的演变，有待进行系统的地理分析研究，而同时汉江流域复杂的土地构成、多元的驱动因素也给常规的地理研究带来了困难。

同时，在经济高速发展的背景下，部分地区不合理的规划开发脆化了原本维持着相对平衡的生态环境，在暴雨、干旱等特定条件下，生态隐患便会以洪涝、滑坡、泥石流等自然灾害形式显现出来^[2]。通过分析汉江中下游流域的景观格局演变情况，总结生态环境平衡被打破的成因，探究汉江中下游流域潜在的生态问题的解决方案，越来越成为如今迫在眉睫的社会需求。