四川杉木混交造林树种选择研究

杉木纯林耗肥力强,自肥力差,引起地力严重衰退,致使杉木采伐迹地上更新的第2、3代杉木林生长差,不能成林。本研究选择桤木、水杉、漆树、灯台、香樟、柳杉和擦木7个自肥力和适应性强的树种与杉木混支造林。其结果表明:混交林枯落物增加;土壤有机质含量比纯林高0.26～3.92％,水解氮高18.1～36.49mg/100g,速效磷高1.46～2.59ppm,速效钾高0.38～0.60mg/100g,土壤肥力明显提高,6年生时,混交林蓄积量比纯杉木林高23.3～117.4％。这7个树种均可作为杉木混交造林的混交树种。

Preliminary Study on Species Selection for Afforesting Mixed China Fir Stand in Sichuan Province

The nutrient consumption of pure China fir (Cunninghamia lanceoluta) stand is very high and its nutrient recycle is very poor, thus causing rapid reduction of soil fertility. The establishment of the second and third generations of afforested China fir is not satisfactory,and in some cases,the artificially planted pure China fir can not form closed canopy. In this work, Alnus cremastogyne, Metasepuoia glyptostrubuides, Rhits uerniciflua, Cornus controuersa, Cinnamomum campliara,Cryptomeria fortunei and Sassafras tsumu which have strong nutrient recycling ability and environmental adaptability, are choosen to afforest mixed forest stand with China fir. The results show: 1. The litterfall of mixed stand increases; 2. The soil fertility of mixed stand is obviously improved. The contents of organic matter,soluble nitrogen, available phosphorus and available potassium of mixed stand are 0. 26% -3. 92%, 18. 11-36. 49 mg/100 g, 1. 46-2. 59 ppm,0. 38-0. 60 mg/100 g more than those in pure China fir stand,respectively. For 6 years old stand, the stocking of mixed stand is 23. 3- 117. 4% higher than that of pure stand. Therefore, the above -mentioned 7 species can be used as mixed components of China fir afforestation.