Man-made versus natural forests in mid-Yunnan, Southwestern China: Plant diversity and initial data on water and soil conservation

Plant diversity, water, and soil conservation of man-made versus natural forests in Mouding (25 degrees 24'09 '' N, 101 degrees 28'18 '' E), mid-Yunnan, were investigated and analyzed. Various plant communities exist in this mountainous region: 4-year-old shrubland, a 10- to 14-year-old plantation of Eucalyptus smithii, a 35- to 45-year-old plantation of Pinus yunnanensis, a 35- to 45-year-old semi-natural forest of Keteleeria evelyniana and Pinus yunnanensis, a 35- to 55-year-old natural secondary forest of Keteleeria evelyniana and Cyclobalanopsis glaucoides, and a climax forest of Cyclobalanopsis glaucoides, Castanopsis orthacantha and Castanopsis delavayi as the original mid-subtropical, semi-moist, evergreen broad-leaved trees in the region. The species diversity and the regenerative quality were poorest under the Eucalyptus forest. The Pinus forest had the lowest interception and stemflow (26.4%) of rainfall, followed by the Eucalyptus forest (29.5%). The leaching loss of nutrients was greater in the two planted forests than in the natural ones. The soil under the Eucalyptus forest was impoverished and showed deterioration of its chemical characteristics, as compared to the shrubland, semi-natural, natural, secondary, and climax forests in the same area.