College of Mathematics and Statistics, Jishou University, Jishou, Hunan, China.
College of Environmental Science and Engineering, China West Normal University, Nanchong, 637009, China.
Environ Monit Assess. 2021 Oct 7;193(11):697. doi: 10.1007/s10661-021-09366-7.
Short-duration high-strength human tourism activities (SHHTA) can result in more air pollution emissions owing to increase motor vehicle usage, energy consumption and cooking fume emissions. Because of the strong uncertainty of human tourism behaviour, it is difficult to accurately assess the impact of SHHTA on air quality of natural scenic spots. To overcome this difficulty, we propose a novel ensemble empirical mode decomposition and detrended cross-correlation analysis (EEMD-DCCA) model to assess the influence of short-duration high-strength human tourism activities (SHHTA) on air quality. Zhangjiajie in China was selected as the study area. Hourly concentrations of NO were analysed from 1 January 2016 to 31 December 2018 at two monitoring sites, in an urban area and a scenic spot. Through EEMD, the main modes of NO with short-duration high-frequency were obtained for both sites. The DCCA method was used to study the cross-correlation relationship between high-frequency modes of NO2 for the urban area and scenic spot. The results show that high-frequency modes of NO between the two sites displayed long-range cross-correlation at the 24-h time scale. Furthermore, the quantitative impacts of meteorological factors (e.g. precipitation, temperature, and wind speed) on the DCCA exponent for high-frequency modes of NO at the two sites were investigated. The novel model proposed in this study is not restricted by the uncertainty of pollution emission inventory. The relationship between meteorological factors and DCCA exponents corresponds to the hypothesis that NO pollution of the natural scenic spot mainly came from SHHTA.
短期高强度人类旅游活动（SHHTA）会增加机动车使用、能源消耗和烹饪油烟排放，从而导致更多的空气污染排放。由于人类旅游行为具有很强的不确定性，因此很难准确评估 SHHTA 对自然风景区空气质量的影响。为了克服这一困难，我们提出了一种新的集合经验模态分解和去趋势交叉相关分析（EEMD-DCCA）模型，以评估短期高强度人类旅游活动（SHHTA）对空气质量的影响。选择中国张家界作为研究区。在城市地区和风景区的两个监测点，从 2016 年 1 月 1 日至 2018 年 12 月 31 日，分析了每小时的 NO 浓度。通过 EEMD，获得了两个站点的具有短时间高频的 NO 的主要模态。使用 DCCA 方法研究了城市地区和风景区的 NO2 高频模态之间的交叉相关关系。结果表明，两个站点之间的 NO 高频模态在 24 小时时间尺度上显示出长程交叉相关。此外，还研究了气象因素（如降水、温度和风速）对两个站点高频模态 NO 的 DCCA 指数的定量影响。本研究提出的新模型不受污染排放清单不确定性的限制。气象因素与 DCCA 指数之间的关系符合自然风景区 NO 污染主要来自 SHHTA 的假设。
