| Increasing level of CO2 in air gives rise to global wanning, which affect the growth, production and distribution of cotton as well. China is the main cotton production country. Climate change can cause the change of temperature suitability of cotton in China. So it is necessary to research on the response of temperature suitability of cotton to temperature change in China to make use of climate resource in different regions.Based on these, using model of temperature suitability, under the technical support of GIS and statistical software, such as ArcView, ArcMap and SPSS, Excel so on, the article calculates the temperature suitability value of cotton from 1961 to 1995 and after temperature changes. The results are the followings:(1) Taking study of other researcher into account and using fuzzy mathematics, the ten-day temperature suitability function is set up by combining with the physiology ecological characteristic of cotton and modifying the parameters, the formula is :S (T)=[(T-T1)(T2-T)B]/ [(T0-T1)(T2-T0)B]B=(T2-T0)/(T0-T1)We find that the function can reflect if the temperature is suitable to the cotton growth through the test. Similarly to the study of temperature suitability of cotton, the GIS methods based on grid map is as good as the method on statistical data through the test.(2) In the total growth stages, the temperature suitability of cotton in the seeding stage and opening stage is low with big change value and sensitive to the temperature change and that in another growth stages are high with low change value.(3) Calculating the average temperature suitability of cotton from 1961 to 1995,we find the temperature suitability in the east is higher than that in the west, and that in the north is than in the south. The distribution of temperature suitability shows some regional characteristics, which are going up from the north to the south; the same is from the west to east. As far as the terrain is concerned, the temperature suitability of cotton of plain ranks first, that of basin runs second, the third is hill land, and themountain is the last one, which is in correspondence to the distribution of temperature. This regularity is caused by the unevenly distribution of solar radiation and from difference of the current terrain with the west higher but the east lower. In the northeast region, the temperature suitability distributes like a belt extending from the east to the west but increasing from the north to the south. The temperature suitability of cotton in the southern China and the middle of China are both higher and centrally distributed. Taking into the terrain account, we can classify China into 5-temperature suitability regions, the Yangtze River valley cotton district, the basin cotton district of the Yellow River, the northwest inland cotton district, South China cotton district, the specially early-maturing cotton district in the north,(4) The change of temperature suitability of cotton is obviously different, which takes on the increasing tendency since 1970s'and that in 1980s' is lower than in 1970s' but increases in 1990s'.The places of temperature suitability changing greatly lie in the northeast and the northwest region, where suitability change are the slightly increase and strong increase and the most suitable area and sub suitable area expands correspondingly. The area with slightly decrease and strong decrease lie in the Changjiang valley and few regions of south china, which are expanding. Climate change makes temperature suitability in some places of in Changjiang river valley and few regions of south china decrease and the area of most suitable area and sub suitable area dwindle. The suitability change is in correspondence with temperature change.(5) Analyzing the change trend of temperature suitability in different districts from 1984to 1995, all districts except the middle region have the ascendait trend, and the Northeast China is the biggest. In East China the change value of temperature suitability is the highest but that in southe...
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