Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China

Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.

Examining the Relationship Between Spatial Configurations of Urban Impervious Surfaces and Land Surface Temperature

The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), but few of them have considered the impact of the spatial configuration of ISA on UHI. Land surface temperature(LST) may be affected not only by urban land cover, but also by neighboring land cover. The aim of this research was to investigate the effects of the abundance and spatial association of ISAs on LST. Taking Harbin City, China as an example, the impact of ISA spatial association on LST measurements was examined. The abundance of ISAs and the LST measurements were derived from Landsat Thematic Mapper(TM) imagery of 2000 and 2010, and the spatial association patterns of ISAs were calculated using the local Moran’s I index. The impacts of ISA abundance and spatial association on LST were examined using correlation analysis. The results suggested that LST has significant positive associations with both ISA abundance and the Moran’s I index of ISAs, indicating that both the abundance and spatial clustering of ISAs contribute to elevated values of LST. It was also found that LST is positively associated with clustering of high-ISA-percentage areas(i.e.,>50%) and negatively associated with clustering of low-ISA-percentage areas(i.e.,<25%). The results suggest that, in addition to the abundance of ISAs,their spatial association has a significant effect on UHIs.

Analysis of the Relationship between Land Surface Temperature and Vegetation and Built-Up Indices in Upper-Hill, Nairobi

Designing “liveable” cities as climate change effects are felt all over the world has become a priority to city authorities as ways are sought to reduce rising temperatures in urban areas. Urban Heat Island (UHI) effect occurs when there is a difference in temperature between rural and urban areas. In urban areas, impervious surfaces absorb heat during the day and release it at night, making urban areas warmer compared to rural areas which cool faster at night. This Urban Heat Island effect is particularly noticeable at night. Noticeable negative effects of Urban Heat Islands include health problems, air pollution, water shortages and higher energy requirements. The main objective of this research paper was to analyze the spatial and temporal relationship between Land Surface Temperature (LST) and Normalized Density Vegetation Index (NDVI) and Built-Up Density Index (BDI) in Upper-Hill, Nairobi Kenya. The changes in land cover would be represented by analyzing the two indices NDVI and BDI. Results showed the greatest increase in temperature within Upper-Hill of up to 3.96&#176C between the years 2015 and 2017. There was also an increase in impervious surfaces as indicated by NDVI and BDI within Upper-Hill and its surroundings. The linear regression results showed a negative correlation between LST and NDVI and a positive correlation with BDI, which is a better predictor of Land Surface Temperature than NDVI. Data sets were analyzed from Landsat imagery for the periods 1987, 2002, 2015 and 2017 to determine changes in land surface temperatures over a 30 year period and it’s relation to land cover changes using indices. Visual comparisons between Temperature differences between the years revealed that temperatures decreased around the urban areas. Minimum and maximum temperatures showed an increase of 1.6&#176C and 3.65&#176C respectively between 1987 and 2017. The comparisons between LST, NDVI and BDI show the results to be significantly different. The use of NDVI and BDI to study changes in land cover due to urbanization, reduces the time taken to manually classify moderate resolution satellite imagery.

Surface Regional Heat(Cool) Island Effect and Its Diurnal Differences in Arid and Semiarid Resource-based Urban Agglomerations

With the rapid development of urban agglomerations in northwest arid and semiarid regions of China, the scope of the urban heat island(UHI) effect has gradually expanded and gradually connected, and has formed a regional heat island(RHI) with a larger range of impact to the regional environment. However, there are few studies on the heat island effect of urban agglomerations in arid and semiarid regions, so this paper selects the urban agglomeration of Hohhot, Baotou and Ordos(HBO) of Inner Mongolia, China as the study area. Based on the 8-day composite Moderate-resolution Imaging Spectroradiometer(MODIS) surface temperature data(156scenes in all) and land use maps for 2005, 2010, and 2015, we analyze the spatiotemporal distributions of regional heat(cool) islands(RH(C)I) and the responses of surface temperatures to land-use changes in the diurnal and interannual surface cities. The results showed that: 1) from 2005 to 2015, urban areas showed the cold island effect during the day, with the area of the cold island showing a shrinking feature;at night, they showed the heat island effect, with the area of the heat island showing a first decrease and then an increase.2) From 2005 to 2015, the land development(unutilized land to building land) brings the greatest temperature increase(ΔT = 1.36°C)during the day, while the greatest temperature change at night corresponds to the conversion of cultivated land to building land(ΔT =0.78°C) exhibited the largest changes at night. From 2010 to 2015, the land development(grassland to building land) bring the greatest temperature increase(ΔT = 0.85°C) during the day, while the great temperature change at night corresponds to the conversion of water areas to building land(ΔT = 1.38°C) exhibited the largest changes at night. Exploring the spatial and temporal evolution of surface urban heat(cool) islands in urban agglomerations in arid and semiarid regions will help to understand the urbanization characteristics of urban agglomerations and provide a reference for the formulation of policies for the coordinated and healthy development of the region and co-governance of regional environmental problems.

Spatiotemporal dynamics of impervious surface areas across China during the early 21st century

China has experienced an unprecedented urbanization and industrialization in the past decades. In this research, we examined the dynamics of construction lands and impervious surface areas (ISA) based on land use/cover change and ISA datasets between 2000 and 2008, which were provided by the national resources and environmental remote sensing information platform. The results indicated that the construction areas and ISA increased by 3468.30 and 2212.24 km 2 /a in this period primarily due to the implementation of national macro-development strategies and fast-growing economy. In 2008, ISA accounted for 0.86% of the total land area in China. Urban land areas increased by 43.46% between 2000 and 2008. The annual growth rate of 1788.22 km 2 /a in this period was 2.18 times that in the 1990s. In particular, urban ISA increased by 53.30% between 2000 and 2008 with an annual growth rate of 1348.85 km 2 /a. During the 8 years, the ISA in China increased rapidly, especially in the Beijing-Tianjin-Tangshan Metropolitan Region, Pearl River Delta, Yangtze River Delta, and the western China region. The increasing ISA may influence potentially water environmental quality in the major basins. In particular, the number of subbasins having ISA of greater than 10% increased considerably, which were primarily distributed in the Haihe River, Yangtze River and Pearl River basins. In 2008, 14.42% of the basin areas were affected by the increased ISA.

基于Landsat8的天津地区夏季城市热岛区分布特征研究

为掌握城市热岛区的分布特征以寻求缓解城市热岛效应的可行方法,选取2013年7月24日和8月25日两景Landsat8天津地区遥感影像,采用单窗算法反演地表温度,并在此基础上,利用Senanayake等提出的方法确定夏季城市热岛区,分析热岛区与植被和水体的关系.结果表明:研究区夏季地表温度平均值约为31.5℃,以中温区和较低温区为主;热岛区的地表温度在36℃以上,所占区域为研究区面积的6.12%,且空间分布不均,呈现市区和塘沽中东部2个中心,景观格局呈零星状和组团状,热岛区斑块面积相差较大;结合实例采用空间叠加法分析热岛区与植被和水体的关系,发现热岛区内几乎无植被和水体分布,说明水体和植被对热岛具有缓解作用.

天津市中心城区典型城市形态原型中建筑形态的热环境效应

以天津市中心城区为例,使用Landsat-8遥感影像反演地表温度(LST),以表征城市热环境。同时,采用建筑数据量化17种建筑形态指标,并识别9种典型城市形态原型。在此基础上,分析不同城市形态原型间的地表温度差异,并用多元线性逐步回归方法探究不同城市形态原型中建筑形态的热环境效应。结果表明:①不同城市形态原型之间的夏季地表温度差异显著,低层高密度区地表温度均值最高,高层低密度区最低;②不同城市形态原型中建筑形态对夏季地表温度均有显著影响,但影响程度存在差异;③不同城市形态原型中各建筑形态因素对夏季地表温度影响方向一致,但重要性存在差异。因此,城市开发和更新中应关注城市形态模式和建筑形态,提出因地制宜的建筑形态调控策略。

数字地价模型在城市地价时空分析中的应用

该文的研究界定了数字地价模型的相关概念,利用加权平均内插法和搜索圆对离散地价样点进行空间插值处理,创建格网文件(grid),借助Arcview平台和自编程序建立了济南市1998年和2001年的数字地价模型。分析数字地价模型得出结论: ①地价从中心基点向城市边缘总趋势是降低,但不同方向表现出不同的特点; ②在贯穿市区的地价剖面中,一般表现为从一个边缘到另一个边缘的地价由低到高再到低的变化规律,由于地价剖面经过不同的市区区位,呈现出正态和偏正态的分布特点; ③在时间演化上,凹性地价阶地变小或变平缓,凹性地价阶地转变为凸性地价阶地,凸性地价阶地变小或转化为非地价阶地,凸性地价阶地变大或平缓; ④利用地价增值率和地价增值速度分析了地价的增值潜力。

城乡结合部土地估价探讨——以石家庄市为例

城乡结合部是城市与农村相互结合的特殊经济地理单元,是城市快速扩张的重点区域,受城市与农村的双重影响。城乡结合部地价是土地价格研究中的薄弱点,土地市场的快速、健康发展迫切要求对该区进行地价评估。该文以石家庄市为例,首先对该区土地进行定级,选择适合城乡结合部土地特征的定级因素:中心城市影响度、交通条件、基本设施状况和自然条件;在定级基础上,综合考虑城市用地与农用地估价的不同特点,采用收益还原法和成本逼近法测算城乡结合部土地价格,并提出了两种方法的局限性和相应的解决方法;最后,对估价结果进行分析,提出城乡结合部土地价格的一些规律性特征:城乡结合部地区由于存在建设用地和农用地之间生地与熟地的差别,不同类型土地之间地价相差很大。文章从理论和方法上对城乡结合部的地价进行了一些探讨性的研究,对进一步明晰城乡结合部的土地产权和土地收益,规范土地交易市场,实现城乡结合部的健康发展有一定的前瞻性和实用价值。

城市不透水面及地表温度的遥感估算

基于植被-不透水面-土壤模型和全约束最小二乘法混合像元分解模型,从探索城市热岛效应和城市不透水面关系出发,利用TM数据对北京市海淀区的城市不透水面丰度和地表温度进行估算,并在此基础上对二者之间的相关性进行定性分析和定量评价。研究表明:城市不透水面的空间分布和变化趋势与地表温度之间存在明显的一致性,二者相关系数达到0.752 5,这说明城市不透水面信息可以很好地反映城市热环境的空间分布状况。

城市土地利用的热环境效应研究--以宁波城区为例

选取宁波城区为研究对象,利用高分辨率的QUICKBIRD多光谱影像数据与Landsat ETM+热红外波段数据探求城市地区土地利用类型的热环境效应。采用剖面分析方法表征宁波城区的热环境空间分异状况;通过热环境效应总体贡献指数与面积加权贡献指数定量分析各种土地利用类型对城市热环境的正负效应。结果表明宁波城区存在热岛效应,建设用地内部地表温度差异明显;工矿仓储用地、平房住宅、交通运输用地、未利用地与公共建筑用地对宁波城区热环境效应具有正向贡献,其中工矿仓储用地最为明显;水域、农用地、生活居住用地和城市绿地对于城市热环境效应具有减缓作用,其中水域最为显著。

意愿调查法在征地区片综合地价评估中的应用——以兰州市安宁区城市规划区征地区片综合地价评估为例

研究目的:确定能否将意愿调查法应用于城市规划区征地区片综合地价评估。研究方法:实例验证法、对比分析法和因果分析法。研究结果:(1)意愿调查法能够兼顾农民、用地单位和政府三方对征地补偿标准的受偿意愿、支付意愿和决策意愿,测算结果更具可执行性。(2)意愿调查法测算出的征地区片综合地价略高于现行的征地补偿标准,符合“适当提高现行征地补偿标准和有利于提高农民现有生活水平[1]”的原则。研究结论:意愿调查法是进行城市规划区征地区片综合地价评估的较好方法。

应用基准地价评估城镇综合用地地价的方法

探讨了应用基准地价结合地价楼层分配系数和基准地价结合面积分摊系数两种测算综合用地价格的方法,同时给出了案例分析,并用剩余法对测算结果进行了验证.还探讨了实际评估过程中易出现的问题.

城镇基准地价内涵及“基准条件”界定研究

针对 90年代我国不同城镇基准地价水平不可比的现象 ,通过对比分析揭示了不同城镇基准地价不可比是由于城镇基准地价评估过程中对基准地价内涵及容积率、建筑密度、宗地深度等条件缺乏明确界定 ,不同城镇基准地价所反映的地价内涵和条件差异很大 ,从而导致城镇间基准地价不可比 ;由此认为新一轮的基准地价更新必须界定基准地价内涵和“基准条件”,并从交易宗地条件及地价形成机制分析入手 ,提出了城镇基准地价内涵及“基准条件”界定的原则、方法和指标体系 .

基于MODIS数据的长株潭地区城市热岛时空分析

基于MODIS影像,采用分裂窗算法反演的地表温度对长株潭地区城市热岛空间分布与季相变化特征、影响因子进行定量研究。结果表明,长株潭地区春季和夏季存在明显的城市热岛效应,而冬季和秋季城市热岛并不明显;地表覆盖类型对城市热岛的影响十分明显,长株潭地区春、夏、秋季植被绿地状况与城市热岛呈现明显负相关分布,其中以夏季最为明显,夏季地表温度与NDVI相关系数的平方R2达到0.8193,即植被覆盖对城市地表温度的影响显著。因此,城市植被的分布与季节变化影响着城市热岛的强度与时空分布,揭示出植被绿地对降低城市热岛效应具有重要的作用,大范围的绿地建设能有效降低城市热岛效应。

四湖流域下垫面改变对排涝模数的影响

选取湖北省四湖流域螺山排区作为研究对象,利用经验公式法计算排涝模数,并分析水面率、水旱比、城市化和灌溉方式及其变化对排涝模数的影响。结果表明:排涝模数随着水旱比和水面率的增加而减小,而随着地面硬化率的增加而增大;水面率对排涝模数的影响大于水旱比和地面硬化率的影响;同水稻的传统灌溉相比,间歇灌溉下的排涝模数较小。由于下垫面条件的改变,在10年一遇3日暴雨的排涝标准下,该地区排涝模数由1994年的0.38m3/(s·km2)上升到2011年的0.46m3/(s·km2),大约相当于1994年下垫面条件下的19年一遇3日暴雨的排涝标准。

三维城市地表反射率计算模式

地表反射率是控制地表能量平衡的一个重要参数。城市建筑物的分布具有较大的不均一性,这不仅给地基观测城市地表反射率带来了很大困难,数值模拟城市地表反射率也是非常困难的。作者开发了一个三维城市地表反射率模式city_photo,该方法结合了蒙特卡洛方法和几何光学方法的优点,具有较高的精度和较快的计算速度。通过引入城市地图的概念,该模式能够计算具有不同结构的城市的地表反射率。2002至2004年晴空MODIS（MODerate Resolution Imaging Spectroradiometer,中分辨率成像光谱辐射计）1-7通道可见光和近红外通道地表反射率资料被用来检验模式的有效性,位于北京朝阳区的中国科学院大气物理研究所的AERONET站点观测得到气溶胶光学特性和水汽资料,6S（Second Simulation of Satellite Signal in the Solar Spectrum）大气辐射传输模式被用来对其进行大气订正。模式计算的北京城市地表反射率个例与MODIS 7个通道地表反射率观测结果具有很高的相关性,相关系数在0.80-0.93之间,说明模式能够较好地模拟城市地表反射率随太阳和观测角度的变化情况。最后讨论了城市结构对城市地表反射率的影响。

城镇土地定级估价成果更新初探——以临漳县为例

社会经济的发展引起城镇土地级别和地价发生变化 ,土地定级估价成果必须及时修订。文章以临漳县为例 ,土地定级采用局部区域与目标级别条件指数对比法 ,土地估价采用地价动态分析指数法和样点地价法 ,探讨了土地定级估价成果的更新方法。

论城市地价空间演化规律及其动因

对城市地价的空间分布研究正在逐步走向成熟，但至今仍未有人对动态分布进行过研究。本文通过对城市地价的空间分布变化规律的分析研究，利用地价平台、地价陡坡等新概念，探索其时间序列上的演化规律及其动因，力图构筑起城市地价四维空间理论的框架；进而探讨了该理论在实践中的一些应用方向和实用价值．

城乡生态经济交错区农地城市流转价格影响因素分析

研究目的:从微观角度分析城乡生态经济交错区农地城市流转价格的影响因素,分析各因素的影响路径。研究方法:指数函数模型定量分析法,实证分析法。研究结果:随着征地地块面积的增大,地价也增大,而用途对土地价格的影响与在城市土地市场出让过程中对土地价格的影响不一致,政府的期望对征地价格有正向影响。研究结论:从微观角度对农地城市流转价格影响因素分析是可行的。目前中国征收集体土地市场虽然主要是政府定价,但随着征地制度的逐步改革,征地补偿逐渐引入市场元素,在一定程度上可通过微观手段调控征地市场。