Undergrowth vegetation niche in scenic-recreational forest communities of Platycladus orientalis and Robinia pseudoacacia in Beijing suburb Variation in Particle Matters of Recreational Forests by the Continued High Temperature Weather in Hui Mountain of Wuxi City Spatial Structure and Scenic Beauty Estimation of Scenic-Recreational Forests of the Tiantai Mountain in Longmenshan National Geopark,Sichuan Principle of Tending Techniques on Recreational Forest of Pinus tabulaeformis in Beijing Mountainous Area by SBE Method Effect of Different Tending Regimes on Scenic Quality of the Platycladus orientalis Recreational Forest Human Comfort Level of Typical Recreational Forests in Mountain Area of Southern Ji’nan in Summer Stand Spatial Structure of Cunninghamia lanceolata Recreational Forest Based on Voronoi Diagram and Delaunay Triangulated Network