| In this paper,2000,2006,2011,2015,2017 and other five phase of Landsat images and MODIS images of 2000-2017 years MOD11A2,MOD13Q1 data processing,Firstly,the support vector Machine(SVM)for Landsat images is classified(supports vector machine).The urban expansion and landscape pattern change of Karamay in Karamay in recent 20 years are obtained;Secondly,the calculation of Karamay surface temperature and vegetation coverage in 2000-2017 years based on Landsat and MODIS image are carried out.The following conclusions were obtained:(1)During the 2000-2017,the high temperature area was concentrated in the Wuerhe of Gobi gradually expanding to the surrounding trend,medium and low temperature distribution in reservoirs,lakes,forest cultivated land.During the 2000-2017,water bodies were at room temperature or low temperature at any time,and water bodies and vegetation had the effect of relieving the thermal environment of the city.Based on Landsat temperature information,the high temperature area of Karamay is distributed in Gobi,the construction land shows the cold island effect,and its temperature is between 25-35 ?;During the 2000-2017 Sanping Reservoir and Aykul Reservoir have been at low temperature,cultivated land is relatively normal temperature state,It shows that water body and vegetation alleviate the urban heat island effect to a certain extent;the temperature of Dushanzi in 2000,surface temperature results is relatively low,while the temperature increases gradually from 2006 onwards,while the temperature in the built area is basically stable and the medium temperature state,and its vegetation and water body are also in the middle and low temperature state.(2)The vegetation cover area of the Karamay of MODIS data increased gradually in 2000-2017,the area with high vegetation coverage increased,and the vegetation was mainly concentrated in the town of small towns and 55 new towns,and in the large agricultural areas developed in the later stage.Landsat based Karamay the change of vegetation area during 2000-2017 is very prominent,especially the high coverage area is greatly increased,in addition to the Wuerhe vegetation area reduction accident the rest of the area increases year by year.(3)The changes of Karamay in the thermal landscape in the past 20 years are basically stable.The landscape indices such as NP,PD,LPI,ED and LSI have not changed much.In the temperature 30-35 ?,35-40 ?,40-42 ?,40-42 ? and other regions of the landscape index has changed and there is a certain change of law,while the area above 42 ? is only 2000,2001,2004,2007,2008,2009,2012,In the 2013 and 2015,and each index is decreasing trend;in the change of vegetation coverage landscape index,the vegetation cover area of Karamay gradually increases,the shape of plaque becomes diversified,the fragmentation degree of vegetation plaque becomes larger,and it is more and more affected by human activities.The landscape index of vegetation in the 2010 was more obvious,while the landscape index of the corresponding surface temperature in 2010 decreased compared with the remaining administrative regions.It shows that vegetation coverage and surface temperature are mutually restricted.(4)2000-2017 Karamay Land Use type area showed an increasing trend,especially after the development of large agricultural areas in 2006,the area of arable land and woodland increased substantially,while grassland was degraded.The area of the built-up area was increasing during the period 2000-2017.The area of Duzishan,Wuerhe and Baijiantan built area is increasing,and the trend of expanding outward.(5)In the analysis of urban landscape pattern,the high value of PD moves outward,which indicates that the urban area has been expanded outward,and the size of the built city has increased,and the value of LPI high value has been evenly distributed from the middle of the city to the outside,and the 2000-2017 NP,PD,DIV,SHDI,The SHEI index shows a growing trend,and the impact of human activities is further enhanced.(6)There is a positive correlation between the construction land and the temperature,which indicates the area with high coverage area,and the temperature of the city is also higher,which is negatively correlated with the vegetation index,which indicates that the area with high vegetation cover and the temperature is also low.From the regression equation,it can be seen that the changes of the construction land and vegetation index will cause the change of temperature,the expansion of the city,the density of the urban complex,and the rapid warming of urban areas. |
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