基于SLEUTH与WRF模式的土地利用变化对城市热环境影响研究

发布时间：2018-03-05 00:29

本文选题：城市空间扩展　切入点：用地适宜性　出处：《南京大学》2015年硕士论文　论文类型：学位论文

【摘要】：城市化导致土地利用类型及格局发生改变,大量的绿地和农田被建设用地代替,下垫面热属性特征与格局相应改变,加上人类生活和生产排放的废热,使城市热岛效应不断加剧、恶化,城市宜居环境受到严重威胁。城市发展对区域热环境变化的影响逐渐被越来越多的人所关注,成为建设宜居、可持续生态城市的热点问题。本文以南京市及其周边区域为研究区,基于研究区的城市发展潜力和生态约束因素,对用地适宜性特征进行分析;在此基础上使用SLEUTH模型预测了 2040年不同情景城市扩展特征;使用WRF模式模拟了未来不同城市扩展情景下热环境变化特征,系统研究了不同城市发展情景下土地利用变化对城市热环境产生的影响;研究结果将为深入理解土地利用变化下城市热环境的空间特征和动态变化规律,对合理的城市发展规划、生态环境的改善与可持续发展提供科学的参考依据。本文共分为五章。第一章为绪论,系统阐述了论文的研究背景与意义,总结国内外相关研究进展,并指出目前研究存在的问题和不足,由此阐明论文的研究目的与技术路线。第二章为数据与研究方法,介绍了研究区的气候、地理位置和论文使用的研究数据以及研究方法。第三章为城市空间扩展的多情景模拟,对研究区进行用地适宜性分析,根据发展理念的差异划分为不同的城市发展情景,使用SLEUTH模型模拟研究区2040年在不同发展情景下的城市扩展特征。第四章为基于WRF模式的土地利用变化对热环境的影响分析,分别使用2013年以及SLEUTH模型预测得到的不同城市扩展情景的土地利用数据对WRF模式默认的土地利用数据进行更新和替换,并对城市热环境进行模拟,分析土地利用变化对城市热环境产生的影响。第五章为结论与讨论,总结论文的研究结论和创新点,并提出研究的不足及将来研究应完善的方向。论文主要结论如下:(1)SLEUTH模型重建结果较好地重现了现实情景下的城市范围,总体精度达到87.91%,重建结果与实际情况比较吻合,具有较好的一致性。SLEUTH模型的模拟结果中城市发展以"边缘增长"和"填充增长"为主,同时在城市的外围形成了新的城市发展中心,形成了"跳跃式"发展。三种城市预测情景中,低生态安全(情景3)下城市发展强度最大,城市范围扩展较大;中生态安全(情景2)次之,高生态安全(情景1)城市面积增长最小。随着城市范围的不断增大,建设用地在城市景观中的优势度不断增大,空间分布趋于集中。农田斑块分布趋于离散化,破碎度不断增大;研究区土地利用格局的景观多样性和异质性减小,景观斑块趋向单一化分布。通过采用不同强度的生态保护策略,有效的避免了城市无序扩张导致的生态斑块(绿地、农田和水体)的消失,兼顾了城市发展与生态保护。(2)WRF模式较好地模拟了研究区热环境的变化特征,近地面气温精度验证结果显示,土地利用修改后的平均误差为-0.2℃C,RMSE为1.24,相关系数为0.94,土地利用修改前的平均误差为-0.6℃C,RMSE为1.25,相关系数为0.95。使用最新的土地利用数据提高了气温的模拟精度,模拟结果更加接近观测值。不同城市扩展情景下的热环境模拟结果显示,城市化将导致近地面气温显著升高,新增建设用地增温明显,高温区面积随着建设用地面积增长不断扩大,城市热岛强度和持续时间也不断增大。(3)土地利用变化是改变城市热环境的重要推动因素,随着城市化进程的不断深入,研究区平均温度不断升高,建设用地平均近地面气温升高幅度较大。农田、绿地、裸地转化为建设用地后,农田的变化对温度的影响相对明显,研究区绿地和裸地的减少对热环境的影响则相对较小。高温区不断向研究区东部和南部蔓延,孤立的高温区斑块逐渐融合并相互连接形成面积较大的高温区。情景3中高温区扩张范围最大,占研究区面积的41.97%,相对2013年增长了 1456.59 km2。次高温区和高温区的范围与建设用地的扩展趋势相一致。低温区、次低温区和中温区的面积则不断减小。从热力景观格局的变化情况来看,低温区、次低温区斑块逐渐消失,空间范围不断缩小,斑块的空间聚集度下降。中温区斑块逐渐被割裂,斑块的完整性遭到破坏,斑块逐渐破碎化。高温区在景观中的优势度和聚集度不断增大,整体性不断增强。建设用地的增长使得热量过于集中,热量集聚现象愈加明显,热量空间分布失衡,城市热环境逐渐恶化。在景观水平2013年热环境格局景观蔓延度和聚集度较小,热力景观斑块分布较为细化和复杂化,景观破碎化程度较高。情景1景观多样性较大,斑块分布较为均匀。情景2和情景3中,高温区范围不断扩大,大量的次高温区斑块转化为高温区斑块,高温区成为景观的优势斑块。情景3中景观蔓延度和聚集度分别达到最大值,景观斑块连接性较好,呈聚集分布。景观的异质性较小,斑块类型相对单一。研究表明未来不同城市发展情景下的土地利用变化将会对城市热环境产生明显的差异性影响,基于城市扩展及热环境模拟与预测的城市规划与管理将为宜居、可持续健康城市的建设提供有力的参考。
[Abstract]:City leading to land use type and pattern change, a large number of green land and farmland construction land is replaced, the surface heat property characteristics and pattern of change, and human life and production of waste heat emissions, so urban heat island effect intensified, deterioration of the city livable environment is a serious threat. Influence of city development on regional heat the environment has been more and more attention and become hot issues of building livable, sustainable ecological city. Taking Nanjing city and the surrounding area as the study area, city development potential and ecological constraints in the study area based on land suitability characteristics were analyzed; on the basis of using SLEUTH model to predict the characteristics of 2040 different scenarios to simulate the future expansion of the city; city expansion and change characteristics of thermal environment in different scenarios using the WRF model, studied the situation of different city development Under the influence of land use change on city thermal environment; the research results will provide in-depth understanding of land use change under the city spatial characteristics of thermal environment and the dynamic changing rules of city, reasonable development plan, to provide scientific reference for the improvement of the ecological environment and sustainable development. This paper is divided into five chapters. The first chapter is the introduction system, expounds the research background and significance, summarizes the related research progress at home and abroad, and points out the present problems and shortcomings, research objective and technical route of this paper. The second chapter is the data and research methods, introduces the climate of the study area, research data and research methods of geographical position and the use of the third chapter for scenario simulation of city spatial expansion in the study area, land suitability analysis, according to the difference of development concept into different city development scenarios, Using SLEUTH model to simulate the features of the different development scenarios in 2040 the expansion of the city. The fourth chapter is based on the land use change WRF model analysis on the influence of the thermal environment, respectively in 2013 and SLEUTH model to predict the different city expansion scenarios of land use data update and replace the default WRF mode of land use data and the city thermal environment simulation, analysis of the effect of land use change on city heat environment. The fifth chapter is the conclusion and discussion, summarizes the research conclusion and innovation, and puts forward the research limitations and future research directions should be improved. The main conclusions are as follows: (1) the reconstruction results reproduce the SLEUTH model the reality of the city limits, the overall accuracy reached 87.91%, compared with the reconstruction results with the actual situation, consistent with the.SLEUTH model better model The results in city development by "marginal growth" and "filling growth", while the formation of a new city development center on the outskirts of the city, forming a "leap" development. The three city scenario, low ecological security (scenario 3) under the city development intensity of the largest city in large range expansion; ecological security (scenario 2) of high ecological security (scenario 1) the area of the city. With the increasing growth of the minimum scope of the city, construction land in the city landscape dominance in increasing spatial distribution tended to be concentrated. Farmland distribution tends to be discrete, fragmentation is increasing; the landscape diversity and pattern reduce the heterogeneity of land use in the study area, the trend of single patch distribution. By using the ecological protection strategies of different intensity, effectively avoid the ecological city sprawl caused by plaque (green land, farmland and water) disappear, taking into account the City Development and ecological protection. (2) WRF model to simulate the variation of the thermal environment of the surface temperature in the accuracy verification results show that the average error of the modified land use is -0.2 C C, RMSE is 1.24, the correlation coefficient is 0.94, the land use changes before the average error is -0.6 C C RMSE, 1.25, the correlation coefficient of land use of the latest 0.95. data is used to improve the simulation accuracy of the temperature, the simulation results are closer to the observations. Different scenarios of city expansion thermal environment simulation results show that the city will lead to the near surface temperature significantly increased, new construction land warming significantly, and high temperature area with the increase of construction land area continues to expand, city heat island intensity and duration has been increased. (3) the land use change is an important push to change the city thermal environment factors, along with the city the process of deepening research on Qu Ping Both the temperature rising, the average surface temperature in the construction land increased greatly. Farmland, grassland, bare land into construction land, farmland change of temperature is relatively obvious, green land and bare land in the study area to reduce the influence of the thermal environment is relatively small. The high temperature zone spread to the South and east of the study area the Ministry, isolated high temperature region gradually fused and connected with each other to form plaque area large high temperature zone. High temperature zone in 3 scenarios the expansion of the scope of the study area, accounting for 41.97%, relative to 2013 growth scope and the construction of 1456.59 km2. high temperature zone and high temperature zone with the expansion trend is consistent. The low temperature zone, low temperature in the area of area and the temperature decrease. The changes of thermal landscape pattern, the low temperature zone, low temperature area gradually disappear, space narrowing, plaque spatial aggregation decreased. In the temperature region The plaque is gradually separated, the destruction of the integrity of the plaque, the plaque gradually fragmented. In view of the advantages of high temperature and concentration increasing, the overall increase of construction land. The growth makes the heat is too concentrated, the heat gathering phenomenon is more and more obvious, the heat distribution imbalance, the City thermal environment gradually deteriorated. The spread of and the aggregation degree is smaller in the landscape level in 2013 of landscape pattern of thermal environment, thermal landscape plaque distribution is more refined and complicated, landscape fragmentation degree is higher. 1 scenarios of landscape diversity, patch distribution is more uniform. Scene 2 and scenario 3 in the high temperature zone, expanding the scope of high temperature zone into high temperature area of plaque plaque, high temperature zone become landscape advantage plaques. Scenario 3 landscape contagion and aggregation degree reached the maximum value, landscape connectivity, aggregated distribution. Compared with the landscape heterogeneity A small plaque, relative to a single type. The results showed that the situation of different city development under the land use change will cause differences influence on the thermal environment in the city, city planning and management of city expansion and thermal environment simulation and prediction based on livable will provide a strong reference for building a sustainable, healthy city.

【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;F301.2

【相似文献】