In the context of climate change, it is of great significance to explore how winter wheat responds to temperature increase in terms of main agronomic traits and dry matter distribution during its growth stage in the tablelands of Guanzhong, Shaanxi, which can provide references for assessing its sensitivity and adaptability under climate change. In this paper, Zhengmai No. 1860 was selected as the research object to analyze the influence of the warming effect simulated by Open Top Chamber (OTC) on the growth and development of winter wheat. The results show that there were significant differences in temperature inside and outside OTC during growth stage (p<0.05) of winter wheat. The average temperature in OTC was 0.8 ℃ higher than that of the outside. In OTC, all the phenological stages of winter wheat came in advance of those in the control group, with an average of 6 days earlier. The plant height inside OTC was higher than that of the outside. OTC promoted leaf area of wheat at the stage of greening and heading, while inhibited leaf area at the stage of flowering and milk ripening.The warming effect promoted root growth, increasing root length by 37.48% and surface area of fine roots by 35.28%, but inhibited root biomass, decreasing it by 7.60%. The warming effect of OTC can promote the dry matter weight of stem, leaf and ear, except the dry matter weight of leaf at milk-ripening stage. In conclusion, OTC can significantly promote the functional traits of winter wheat at the vegetative growth stage, but at the reproductive growth stage, it can not promote the functional traits and even show a certain inhibitory effect.

In order to study the transport characteristics of air pollution in Linfen City, based on the hourly air quality index (AQI) data in Linfen City from the Ministry of Ecology and Environment from 2016 to 2017, the six-hour reanalysis data and the global data assimilation system (GDAS) data with a horizontal resolution of 1°×1° from the National Centers for Environmental Prediction (NCEP), the influence of topography and weather situation on air pollution during the 24 pollution processes in Linfen City was analyzed by using backward trajectory clustering analysis of HYSPLIT4 (hybrid single-particle lagrangian integrated trajectory) model. The results are as follows: (1) The sea-level circulation situation during the 24 pollution processes mainly included the following six types: front of Mongolian high pressure bottom type, front of low pressure type, rear of North China high pressure type, front of invert trough near the Hetao area type, uniform pressure field and low pressure belt type. (2) The 24 h and 60 h backward trajectory can represent the impact of topography conditions and weather conditions on pollution in Linfen City, respectively. (3) The 24 h backward trajectories show that the air flow can sink and transport pollutants along the leeward slope of the Lüliang Mountain. The pollution in Linfen City was formed from inverted “concave” shape terrain opening to the south and the southwest wind near the ground. The air flow can also return to Linfen City after touching the surrounding mountains. Among them, the transportation along the subsidence of the Lüliang Mountain from the northwest direction was main. (4) The 60 hour backward trajectories show that the air flow transporting pollutants met with the easterly or southerly airflow under the influence of the weather situation, and then turned back to Linfen City. The pollutant particles hygroscopic grew with the increase of humidity caused by southwesterly or easterly wind. The topography and weather situation have an impact on the transport route of air pollution in Linfen City.