生态环境学报
生態環境學報
생태배경학보
ECOLOGY AND ENVIRONMENT
2014年
10期
1622-1627
,共6页
城市热岛效应%道路密度%热贡献%Modis%热岛强度
城市熱島效應%道路密度%熱貢獻%Modis%熱島彊度
성시열도효응%도로밀도%열공헌%Modis%열도강도
urban heat island effect%road density%thermal contrubution%Modis%heat island intensity
热岛效应是城市气候最显著的特征之一。土地利用方式及土地覆盖的改变,如城市化和道路建设是导致热岛现象的重要原因之一。然而目前针对道路属性(道路密度及类型)对城市热岛效应的影响研究还较缺乏。本研究运用2012年成都市不同时次(冬夏季)的遥感数据及城市道路交通专题图,运用3S技术探讨道路密度对城市热岛效应的影响以及不同类型道路对城市热岛效应的热贡献。研究表明:(1)成都市热岛效应明显,市区地表平均温度显著高于郊区且热岛强度呈现夏强(3~4℃)冬弱(2.5~3℃)、夜强昼弱的特征。日间城市热岛效应呈现多热中心的分布模式,但冬夏季热岛中心位置不同。夏季日间热中心位于城市的西南部和中东北部,最高可达32.66℃,而冬季日间城市的西南部地表温度较高且热中心主要分布于城市边界地区,地表温度超过16℃。无论冬夏,夜间城市热岛效应均呈现环状分布特征,即从城市边缘到中心,地表温度逐渐升高,夏季城乡地表温差高达4.37℃而冬季达到2.82℃。(2)成都市区道路呈现“圈层型+辐射型”分布模式,道路密度与道路的分布有关,城市南部及西南部的道路密度高于北部区域。(3)无论冬夏,道路密度与地表温度正相关,但两者相关性呈现昼弱夜强的特征,其中夜间相关系数达到0.5左右。对热效应贡献度指数、热单元权重指数、区域热单元权重指数3个指标的分析都表明无论冬夏、无论昼夜,市区分布面积最广的三级道路对城市热岛效应的热贡献最大,其热效应贡献度指数均在95%以上,其次是二级道路,各项热效应贡献度指数为45%~80%。本研究结果将有助于未来城市建设和道路规划,并为缓解城市热岛效应提供理论支持。
熱島效應是城市氣候最顯著的特徵之一。土地利用方式及土地覆蓋的改變,如城市化和道路建設是導緻熱島現象的重要原因之一。然而目前針對道路屬性(道路密度及類型)對城市熱島效應的影響研究還較缺乏。本研究運用2012年成都市不同時次(鼕夏季)的遙感數據及城市道路交通專題圖,運用3S技術探討道路密度對城市熱島效應的影響以及不同類型道路對城市熱島效應的熱貢獻。研究錶明:(1)成都市熱島效應明顯,市區地錶平均溫度顯著高于郊區且熱島彊度呈現夏彊(3~4℃)鼕弱(2.5~3℃)、夜彊晝弱的特徵。日間城市熱島效應呈現多熱中心的分佈模式,但鼕夏季熱島中心位置不同。夏季日間熱中心位于城市的西南部和中東北部,最高可達32.66℃,而鼕季日間城市的西南部地錶溫度較高且熱中心主要分佈于城市邊界地區,地錶溫度超過16℃。無論鼕夏,夜間城市熱島效應均呈現環狀分佈特徵,即從城市邊緣到中心,地錶溫度逐漸升高,夏季城鄉地錶溫差高達4.37℃而鼕季達到2.82℃。(2)成都市區道路呈現“圈層型+輻射型”分佈模式,道路密度與道路的分佈有關,城市南部及西南部的道路密度高于北部區域。(3)無論鼕夏,道路密度與地錶溫度正相關,但兩者相關性呈現晝弱夜彊的特徵,其中夜間相關繫數達到0.5左右。對熱效應貢獻度指數、熱單元權重指數、區域熱單元權重指數3箇指標的分析都錶明無論鼕夏、無論晝夜,市區分佈麵積最廣的三級道路對城市熱島效應的熱貢獻最大,其熱效應貢獻度指數均在95%以上,其次是二級道路,各項熱效應貢獻度指數為45%~80%。本研究結果將有助于未來城市建設和道路規劃,併為緩解城市熱島效應提供理論支持。
열도효응시성시기후최현저적특정지일。토지이용방식급토지복개적개변,여성시화화도로건설시도치열도현상적중요원인지일。연이목전침대도로속성(도로밀도급류형)대성시열도효응적영향연구환교결핍。본연구운용2012년성도시불동시차(동하계)적요감수거급성시도로교통전제도,운용3S기술탐토도로밀도대성시열도효응적영향이급불동류형도로대성시열도효응적열공헌。연구표명:(1)성도시열도효응명현,시구지표평균온도현저고우교구차열도강도정현하강(3~4℃)동약(2.5~3℃)、야강주약적특정。일간성시열도효응정현다열중심적분포모식,단동하계열도중심위치불동。하계일간열중심위우성시적서남부화중동북부,최고가체32.66℃,이동계일간성시적서남부지표온도교고차열중심주요분포우성시변계지구,지표온도초과16℃。무론동하,야간성시열도효응균정현배상분포특정,즉종성시변연도중심,지표온도축점승고,하계성향지표온차고체4.37℃이동계체도2.82℃。(2)성도시구도로정현“권층형+복사형”분포모식,도로밀도여도로적분포유관,성시남부급서남부적도로밀도고우북부구역。(3)무론동하,도로밀도여지표온도정상관,단량자상관성정현주약야강적특정,기중야간상관계수체도0.5좌우。대열효응공헌도지수、열단원권중지수、구역열단원권중지수3개지표적분석도표명무론동하、무론주야,시구분포면적최엄적삼급도로대성시열도효응적열공헌최대,기열효응공헌도지수균재95%이상,기차시이급도로,각항열효응공헌도지수위45%~80%。본연구결과장유조우미래성시건설화도로규화,병위완해성시열도효응제공이론지지。
The heat island effect is often one of the most evident characteristics of urban climates. Land use/cover changes such as urbanization and road building, are some of the most important factors that induce heat islands. Road properties, including road density and road type, may determine the magnitude of urban heat islands, but such effects have not previously been explored. In this study, we evaluated the effect of road density and the contribution of different road types on urban heat islands using multi-time (winter and summer) Modis data and city transportation maps with 3S technology. The results showed that: (1) The urban heat island effect in Chengdu was very apparent and of high intensity in summer (3~4℃) but weak in winter (2.5~3℃). During daytime, there was a polycentric pattern of heat island, and the central of heat island varied between summer and winter. In summer, the areas with the highest land surface temperature (32.66℃) was in the southwest and the central northeast part of the city. In winter, the land surface temperature in the southwest section of the city and at the city boundary was higher, oftern over 16℃. At night, there was a ring distribution pattern of the urban heat island both in summer and winter, and the land surface temperature decreased from the central of the city to the suburbs. The difference of the land surface temperature between the city and suburbs was 4.37℃ in summer and 2.82℃ in winter;(2)The road system in Chengdu showed a “ring and radiative” distribution pattern, and road density was closely related to the road distribution. The road density in the south and southwest part of the city was higher than that in the northern part;(3)Both in winter and summer, the land surface temperature was significantly correlated with road density, and the coefficient correlation was higher at night (r=0.5) than that in daytime. Thermal contribution index, thermal unit weight index and thermal unit weight index indicated that the third-class roads contributed the most to the urban heat island effect (>95%), much greater than secondary road (45%~80%). These results are expected to provide critical information for decision makers and land managers for management of urbanization and road building, which may mitigate the urban heat island effect.