Studies on the dynamics of patch size and grain structure of landscape elements in the forest restoration process SPATIAL CORRELATION INDICES AMONG FOREST LANDSCAPE STRUCTURAL COMPONENTS AND LANDSCAPE PATTERN ANALYSIS IN GUANDISHAN FOREST REGION Species Diversity in Overlapped Zones of Typical Secondary Forests in Guandishan Mountains Decomposition process and nutrient dynamic of litterfall in a Larix principis\|rupprechtii stand in Guandishan Mountains