Effects of Thinning Intensities on Cunninghamia Lanceolata Growth and Soil
The effects of thinning intensity on understory vegetation and soil characteristics of Cunninghamia Lan-ceolata in state-owned forest farm were analyzed.A Cunninghamia Lanceolata forest base was selected from the Muse State-owned Forest Farm in Chishui City,Zunyi City,Guizhou Province,and four treatments were divided according to different thinning intensity.CK(no thinning),Z1(thinning intensity 20％),Z2(thinning intensity 30％)and Z3(thinning intensity 50％)were used to investigate the vegetation quantity and soil characteristics of Cunninghamia Lanceolata under different thinning intensity.The newly added species of shrubs,herbs and vines under Z2 treatment were higher than those under other treatments.The newly added species of shrub plants under Z2 increased 2.8 times,2 times and 1.4 times compared with CK,Z1 and Z3,respectively,and the newly added species of herbs increased 2.33 times,2 times and 1.4 times compared with CK,Z1 and Z3,respectively.Compared with CK,Z1 and Z3,the new species of vines increased 2.75 times,1.83 times and 1.38 times,respectively.The av-erage DBH growth,average tree height growth,average stock growth and average volume growth of Z2 treatment were higher than those of other treatments(P＜0.05).Under different thinning intensities,the vegetation diversity of Cunninghamia Lanceolata forests was Z2＞Z1＞Z3＞CK,indicating that the tending of Cunninghamia Lan-ceolata with thinning intensity of 30％was more conducive to the increase of plant diversity than that without thinning,thinning intensity of 20％and thinning intensity of 50％.The available phosphorus,alkali-hydrolyzed nitrogen,available potassium and organic matter of Z2 treatment were higher than those of other treatments(P＜0.05),and there was no difference in pH of the four treatments(P＞0.05).The overall trend was Z2＞Z3＞Z1＞CK.Different thinning intensities affect the growth of Cunninghamia Lanceolata.Thinning intensities of 30％can maintain the stability of Cunninghamia Lanceolata forest ecosystem,increase the vegetation diversity of Cunning-hamia Lanceolata forests,improve the soil properties of Cunninghamia Lanceolata forests,and promote the growth of Cunninghamia Lanceolata forests.
万方数据
维普
