基于景观的干旱区城市热岛效应变化研究——以乌鲁木齐市为例

Study on Urban Heat Island Effect based on Landscape Distribution in Arid Area——Taking Urumqi in China as Example

尝试将景观生态学的方法应用到热岛效应研究中,以绿洲城市乌鲁木齐市为典型研究区,基于1987—2005年间景观变化开展城市热岛效应时空变化分析。在地表温度反演和景观分类的基础上,通过划分温度景观类型,计算景观指数,构建温度景观评价体系。结果显示,近20 a来,研究区温度景观的多样性指数由1.0395持续增加至1.2834,破碎度指数由0.1092先增至0.1834,后减到0.1616,聚集度指数也由58.9862持续降至48.9043,反映了温度景观的异质性和破碎化程度在增加,斑块呈现密集格局。在城区内部,各类城乡建设用地温度景观在1987年至1999年呈现高度破碎,到2005年部分碎片聚合,特高温城乡建设用地在此过程中变化尤为显著,热中心由热碎片形成了热团块,趋于稳定趋势。

Urban heat island is the most prominent characteristic of the temperature influenced by activity of human being, and has aroused widespread interests due to its effect on global warming, which therefore automatically leads to a newly-round academic craze on the research of climate, ecology and environment. With the acceleration of urbanization, urban heat island has gradually flown out of the water in the arid land. The present result is that there is a severe restriction on the city development of Urumqi and the health of its residents, both physically and psychologically due to the phenomenon of Urban Heat, Urban Dry, and Ur- ban Turbidity. Based on temperature landscape distribution, change of heat island effect is studied from 1987 to 2005. Through the construction of appraisal system of temperature landscape, the following results are discovered： each type of temperature landscape in the city increased continually along with the urbanized advancement. The around high-temperature bare land being the main extended source, the urban heat island effect tends to be spreading. Many landscape indexes have been used to evaluate changes in temperature landscape and theirs shows that the landscape diversity and fractal dimension increased. Heating conglomeration, which formed by heating fragments in the-highest-temperature building represented the heating center.