近十年长沙热环境空间格局演变研究

发布时间：2018-05-16 07:00

本文选题：热环境 + 空间格局　；参考：《南京大学》2015年硕士论文

【摘要】：城市热环境是生态环境效应的研究热点,热环境演变规律的研究为缓解城市热岛效应、促进城市可持续发展提供依据。长沙作为"中部崛起"的战略支撑点,城市化进程快速推进,进一步加剧了城市发展与生态环境的矛盾。对于长沙城市热环境时空演变规律,以及地表温度差异与景观类型空间格局之间关系的研究不仅有利于缓解长沙城市热岛效应,改善城市生态环境,而且对于中西部区域中心城市具有借鉴和参考价值。本文以长沙作为热环境演变规律研究的典型区域,选取2000-2013年Landsat系列的TM、ETM+、TIRS传感器数据,分别采用重心迁移、空间自相关、移动窗口和梯度分析、空间回归模型等方法,从年际变化和季节变化两方面详细研究长沙热力景观重心迁移演变、空间集聚和格局变迁特征,并定量分析了城市景观类型组成和空间格局与热环境的关系,主要研究内容和结论包括:(1)热环境时空变化分析。研究从年际变化和季节变化两个方面,揭示长沙地表温度空间分布变化、热力景观空间分布变化和热力景观重心迁移变化的规律。发现2000-2013年长沙热岛区域不断扩大,面积增加了 96.80km2,且分布更加分散,新增的热岛区域主要集中于河西岳麓开发区、南部天心和雨花工业园以及东部星沙经开区,这与政府"东提西布,南延北扩"发展布局有关。热岛景观(高温区和次高温区)的转移规律与城市重心转移规律吻合程度较好,总体格局向东北偏移,而次低温区和低温区的转移方向与高温区大致相反。2013年不同季节高温区和次高温区重心转移方向一致,随着时间变化,先向西北方向再向东南方向偏移,低温区重心随着季节变化从东部向西部偏移。(2)热力景观空间格局演变特征。研究使用全局Moran's I和LISA指标分析长沙热环境空间集聚格局的总体特征和局部特征,在景观水平上对2000-2013年不同年份、2013年不同季节各景观指数的变化趋势进行分析,在此基础上,结合梯度分析与移动窗口对8个方向上长沙热力景观空间格局进行研究。结果表明:2000-2013年长沙热环境空间分布呈集聚现象,高-高集聚区域面积随时间变化逐渐增加,低-低集聚区随着时间变化向北迁移,分布离散化。2000-2013年长沙热力景观变得愈加破碎、离散化,景观形状趋于复杂,西北、正南、正东方向上热力景观面积周长分维度指数(PAFRAC)和香农多样性指数(SHDI)不断增大,城郊热力景观格局变化大,呈现破碎、复杂化趋势。(3)地表景观格局的热环境效应。利用数值分析和地表景观变化图谱等方法,分析地表景观的温度变化特征,并利用不同空间尺度下各景观类型面积所占百分比表征景观类型的空间组合格局,构建空间回归模型定量分析景观组合与地表温度关系。耕地、林地在研究区内的景观优势度越高、空间分布越集中,降温效果越显著;反之,建设用地优势度越明显、凝聚程度越高、景观形状越规则,地表温度越高,热岛效应显著。研究发现在900m尺度下空间误差模型拟合效果最佳,各景观类型的系数估计值均通过0.01的显著性检验,模型的整体拟合优度(R2)为0.8951。耕地、草地、林地、城市绿地和水域的系数估计值分别为-0.0292、-0.0158、-0.0244、-0.0209、-0.0488,这表示在一定格网单元内,当耕地面积增加1%(相应建设用地面积减小1%),地表温度降低0.0292℃。以同等比例增加时,水域、耕地和林地对地表温度有较强的降温效应,在缓解城市热岛效应方面起到关键性作用。
[Abstract]:Urban thermal environment is the research hot spot of ecological environment effect. The research of thermal environment evolution law provides the basis for alleviating urban heat island effect and promoting urban sustainable development. As a strategic support point of "the rise of central China", Changsha rapidly advances the process of urbanization and further aggravates the contradiction between urban development and the ecological environment. The urban heat of Changsha is hot. The study on the spatio-temporal evolution of the environment, the relationship between the difference of surface temperature and the spatial pattern of landscape type not only helps to alleviate the Changsha urban heat island effect, improve the urban ecological environment, but also has the reference and reference value for the central and western regional central cities. This paper takes Changsha as the typical area of the research of the thermal environment evolution law. The TM, ETM+, and TIRS sensor data of the 2000-2013 year Landsat series are selected, and the migration, spatial autocorrelation, moving window and gradient analysis and spatial regression model are used respectively to study the migration and evolution of the center of gravity of Changsha thermal landscape, the spatial agglomeration and the pattern change characteristics from two aspects of the interannual and seasonal changes. The main contents and conclusions of urban landscape type and spatial pattern and thermal environment are as follows: (1) analysis of spatio-temporal changes in thermal environment. From two aspects of interannual and seasonal changes, the study reveals the spatial distribution of surface temperature in Changsha, the spatial distribution of thermal landscape and the law of the migration and change of the center of gravity of the thermal landscape. 20 In 00-2013, the area of Changsha heat island expanded, increased 96.80km2 and distributed more. The new heat island area was mainly concentrated in the Yuelu Development Zone of Hexi, the southern Tianxin and the Yuhua Industrial Park and the eastern Xingsha open area. This is related to the government "East Tisib, South extension North expansion". The transfer law of the center of gravity is in good agreement with the urban center of gravity transfer, and the overall pattern is shifted to the northeast, while the transfer direction of the sub low temperature and the low temperature regions is in the opposite direction to the high temperature region in.2013 years. With the seasonal changes from the east to the West. (2) the characteristics of the spatial pattern evolution of the thermal landscape. The overall characteristics and local characteristics of the spatial agglomeration pattern of Changsha thermal environment were analyzed using the global Moran's I and LISA indexes. In the landscape level, the change trend of the landscape index in different seasons in different seasons in the 2000-2013 years in 2013 was carried out. On this basis, the spatial pattern of Changsha thermal landscape in the 8 directions was studied with gradient analysis and moving window. The results showed that the spatial distribution of thermal environment in Changsha was concentrated in 2000-2013 years, the area of high and high agglomeration increased gradually with time, and the low low concentration area migrated northward with time, and the distribution was dispersed. In the past 2000-2013 years, the thermal landscape of Changsha has become more and more broken, dispersed, and the landscape shape tends to be complex. The thermal landscape area of the northwest, the south, the East and the East, the perimeter fractal index (PAFRAC) and the Shannon diversity index (SHDI) are constantly increasing, the thermal landscape pattern of the suburb is changed greatly, and the trend of the landscape is broken and complicating. (3) the thermal environment of the landscape pattern By means of numerical analysis and landscape change atlas, the characteristics of surface landscape temperature change are analyzed, and the spatial composition pattern of landscape type is characterized by the percentage of various landscape types under different spatial scales, and a spatial regression model is constructed to quantitatively analyze the relationship between landscape combination and surface temperature. The higher the landscape advantage degree is, the more concentrated the spatial distribution is, the more significant the cooling effect is. On the contrary, the more obvious the advantages of the construction land, the higher the cohesion, the more regular landscape shape, the higher the surface temperature and the significant effect of the heat island. It is found that the spatial error model fitting effect is the best in the 900m scale, and the coefficient estimates of the landscape types are all through. After 0.01 significant tests, the overall goodness of fit (R2) of the model is 0.8951. arable land, grassland, woodland, urban green space and water area are estimated to be -0.0292, -0.0158, -0.0244, -0.0209, -0.0488 respectively. This indicates that in a certain grid unit, the ground surface temperature decreases by 1% (the area of the corresponding construction land is reduced by 1%), and the surface temperature is reduced by 0.0292. When the proportion increased, water, cultivated land and woodland had a strong cooling effect on land surface temperature, and played a key role in alleviating urban heat island effect.

【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X16;P901

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