Study on The Relationships between Ground Bright Temperature and Land-use Types of City Based on Landsat Image

Abstract

Reducing the effect of heat island by environment construction is one of the key aspects for city development. With Landsat5 TM image of the year 2007 as the data source, this paper first has an inversion of the land surface temperature of Chongqing city with mono-window algorithm; secondly it gives a partition of the planetary brightness temperature hierarchical, and thirdly it studies both the intensity of Chongqing urban heat-island effect and heat field analysis and the relationship between the urban land use type and the effect of heat island, thermal field level and profile analysis. The above analysis indicates that the urban island effect is notable and it is not well-distributed; the influences of different land-use types on the heat-island effect vary. And finally combining the actual situation of the researched area, this paper proposes some countermeasures and solutions for alleviating the urban heat-island effect, including enhancing the urban planning and adjusting the city layout; constructing the optimal structures of the green belts and improving the urban green coverage rate; changing the structure of energy sources, improving the efficiency of the energy utilization and controlling the petrol-engine waste gas emission of factories. The urbanization is an inevitable tendency of the social development. With the rapidity of urbanization, the effect of heat island strengthens. The city heat island is a kind of city public hazard; the high temperature generated will not only severely threaten the human health, but also lead to pressure difference between the city and the country which will further cause the air circulation between urban and rural areas and aggravate the city air-pollution. Besides, the effect of heat island increases electricity use and water use sharply and exacerbates the intensive situation of the supply of the water, electricity and coal and acts negatively to the city life. In order to weaken and eliminate the negative effects, scholars both at home and abroad have been giving researches to the