Effects of Thinning on Community Characteristics of Larix principis-rupprechtii Plantations in Hebei, China

The plots of thinning intensity with five different treatments of C(control), L(35.48%), M(43.15%) , H(57.66%) and G(81.85%) on the undergrowth, carried out in the Larix principis-rupprechtii plantations of Saihanba forestry centre, Hebei province of China, were repeated four times respectively in order to find out the effects of thinning on community characteristics of Larix principis-rupprechtii plantations. By means of field investigation and statistical analysis, results are as follows: 1) The different thinning intensities have changed ecological conditions of forest and regulated the stand density which has the significant effects on the height growth and girth growth of Larix principis-rupprechtii plantations. 2) The first dead branch height and fresh one present the increasing tendency with the increase of the thinning intensity. 3) Different thinning intensity has different dominant species of undergrowth vegetation and these vegetations happen to succession from shade plants to sun plants. 4) Thinning can improve species richness and diversity.