Abstract: The characteristics of climatic change within a year and between years in Shapotou region were studied. By means of functional spectral analysis we studied quantitatively the periodic oscillations of temperature and rainfall. Using cross over functional spectral analysis method we studied the mechanism of coordinated changes, periodicity and their influences on planted vegetation of temperature and rainfall. The main conclusions are as follows: (1) The temperature of this region fluctuates to a large extent within a year, but little between years. Statistical data show that the average temperature of January is -6.7℃, and that of July is 24.1℃; the yearly fluctuation is between 8.8℃ and 10.2℃. The functional spectral analysis of temperature change s hows that its yearly change exhibits the periodicities of 7.2 years, 3 years an d 2.4 years. (2) The average rainfall in this region is 182 mm, and the distribution within a year is uneven: about 87% of total rainfall concentrates on the period of June to October, with peak in August. The yearly fluctuation of rainfall is violent and the largest coefficient of variation reaches 63%. The functional spectral analysis of yearly fluctuation of rainfall demonstrates that the average rainfall per year exhibits the periodicities of 8.4 years, 5 years, 3.5 years and 3 years. (3) The temperature and rainfall in this region coincides seasonally, forming dry cold winter and moist hot summer. The spring and autumn are relatively dry, so spring plants germinate late and stop growing early in autumn. The joint action of temperature and rainfall shortens the growth period of plants in this a rid region. The results of cross over functional spectral analysis of water and temperature show that the coordinated effect of water and temperature has periodicities of 9 years, 7.2 years and 3~3.2 years. The above conclusions are in accordance with observational results. Main conclusions provide quantitative basis for the efficient utilization of climatic resources and establishment of sand fixing vegetation in this region.

Key words: Climatic resources, Characteristics, Functional spectral analysis