The Response Of Air Quality To Tourist Number In Typical Tourist Cities By EEMD And DCCA Statistical Method

In recent years,there is a fast development of tourism industry in China.People prefer choose the natural scenic spots with good air quality for travel and vacation.But the air quality problem in tourist cities has attracted more and more attention because of the disorderly development of some tourist destinations and explosive growth of tourist population.Atmospheric pollutant emission is the most direct cause of urban air quality decline.The time series of urban atmospheric pollutant concentration and number of tourists show non-linear and non-stationary time scale characteristics because of the meteorological factors and tourism policies.Especially the current human tourism activities show short-term,high-intensity characteristics.It is difficult to separate short-cycle and high-intensity human tourism activities from complex human tourism sequences with the traditional statistical methods.It caused that traditional statistical methods can not describe the dynamic characteristics of the changes and the relationship between them clearly,comprehensively and accurately.The present paper is aimed to study Relationship between human tourism activities and atmospheric pollutant concentrations in Zhangjiajie City,Hunan.Select the tourist number of WuLingYuan and TianMen Mountain scenic spot and the daily average concentration of pollutants data such as NO₂ and PM_2.5.5 during 2015 to 2017 as research data.The data come form 4 national air quality monitoring site?Yuanjiajie,Weiyang Road,Electric Power Bureau and Yongding New District?.Using Ensemble Empirical Mode Decomposition method and Detrended Cross-Correlation Analysis method to analyze the characteristics of short-cycle high-intensity human tourism activities and their impact on urban air quality from three steps.Firstly,analyze the normality,non-stationarity and trend of the research data by statistical parameters and statistical methods.Secondly,Using the ensemble empirical mode decomposition?EEMD?method to decompose all time series and figure out the period and variance contribution rate of each IMF.Thirdly,using the DCCA method analyzed the long-range correlations between short-term,high-intensity human tourism activities of Wulingyuan?Tianmen Mountain and atmospheric pollutant concentrations of NO₂,PM_2.5.And also analyzed the long-range correlations between the tourism numbers of Wulingyuan?Tianmen Mountain scenic spot.And studied the long-range correlations of Concentration of atmospheric pollutants between different scenic spots.The results show that:?1?The tourists number of Wulingyuan and Tianmen Mountain scenic spot and the concentration of atmospheric pollutants in Zhangjiajie showed non-stationary,nonlinear and multi-scale variation characteristics.?2?The atmospheric pollutants has a significant positive correlation with short-cycle high-intensity human tourism activities in Zhangjiajie.This correlation has long lasting characteristics,and gradually weakened with time.?3?The tourist number of Wulingyuan and Tianmen Mountain scenic spots shows the relationship between competition and linkage.In the short period,the tourist number of two scenic spots showed a negative correlation,showing a competitive relationship.With the increase of tourism time cycle,the tourist number of two scenic spots is positively correlated which is long-term sustainability.It is shown as a linkage relationship.?4?There is a strong long-lasting positive correlation between the same atmospheric pollutant concentration monitored in different scenic spots in Zhangjiajie.The research of this paper can provide theretical basis for the development of tourism and environmental pretection plocies in Zhangjiajie city.It also provides a scientific statistical method for the quantitative assessment of the impact of human tourism activities on urban air quality.