Impact of agricultural tourism activity on the soil environment in karst regions

In order to clarify the influence of leisure agriculture tourism activity, which is booming in eastern Sichuan, on the soil ecological environment and provide a scientific basis for assessing the impact of agricultural tourism activity on the environment in the future. This paper takes the soil sample regions of tour trail on both sides of Chongqing Beibei Jinguoyuan(leisure sightseeing orchard) (hereinafter refers to as the "Jinguoyuan") and Huangjiaomen Tongliang area, Qicaimengyuan (yellow door modern agricultural park) (hereinafter refers to as "Qicaimenyuan") as the research objects. Using the quadrat method of two parks on either side of the main route, the soil samples are investigated. Through on-site survey and laboratory analysis on samples, this work systematically studied the soil environment affected by the distance, the ecological index hit rule and its potential risk. Results show that in both the areas affected by the agricultural recreation, the soil moisture content, soil organic matter, soil total nitrogen and alkaline hydrolysis nitrogen decrease with the decreasing distance from trails. The soil bulk density rises with the decrease of the distance from trails, while the soil pH value only in the Qicaimengyuan presents a rising trend with the decrease of the distance from trails. Each index of the affected range is mainly concentrated in the range of 4 m. The trampling index analysis shows that the two parks are in a state of mild trample. The soil humus layer and herb have not been completely destroyed and soil ecological environment under the natural state can be restored. Evaluation the soil heavy metal content of the two parks indicates that in general every area of soil is in a clean environment or still clean state. The Cd and Pb content in the part of the sample zone reaches the security alert (pollution index > 0.7) where it needs to take measures to prevent and control as a focused object.