粤北地区杉木林与阔叶纯林土壤肥力特征

以粤北地区杉木(Cunninghamia lanceolata)林及6种典型阔叶纯林为研究对象,分析和比较了不同林分类型的林下土壤肥力状况,通过主成分分析法对不同林型下土壤肥力进行综合评价。结果表明:火力楠(Michelia macclurei)林、乐昌含笑(Michelia chapensis)林和杉木林土壤孔隙度及土壤层持水性各指标较其他林分高。7种纯林土壤pH为4.28~4.78,属强酸性土壤。各林型间土壤全氮、碱解氮质量分数,红锥(Castanopsis hystrix)林最高,香樟(Cinnamomum camphora)林最低。不同林型的土壤有机质质量分数不同,其中杉木林最高(32.91 g·kg^-1),香樟林最低(12.07 g·kg^-1)。7种人工林的土壤全磷、全钾质量分数均较低,且有效磷质量分数均小于3 mg·kg^-1,整体水平偏低。土壤肥力由高到低综合排序为火力楠林、乐昌含笑林、杉木林、红锥林、香樟林、米老排(Mytilaria laosensis)林、木荷(Schima superba)林,表明该区杉木林下土壤肥力较高,采取适当措施可提高其生态效益和经济效益。

Soil Fertility of Chinese Fir and Several Typical Broad-leaved Pure Forests in Northern Guangdong

The soil fertility of different forest stands of northern Guangdong was investigated based on principal component analysis method. The results illustrate that Michelia macclurei forest, M. chapensis forest and Cunninghamia lanceolate(Chinese fir) forest had higher soil porosity and water holding ability than those of other stands. The pH value of soil of the forest stands spanned from 4.28 to 4.78. Castanopsis hystrix forest had the highest content of total nitrogen and available nitrogen among different forest types, and the lowest one was still in Cinnamomum camphora forest. Soil organic matter of different forest stands seemed to be different, Chinese fir forest appeared to be the highest one(32.91 g·kg^-1), while camphor forest was the lowest one(12.07 g·kg^-1). The content of total phosphorus and total potassium in soil of the present stands was low. And the content of available phosphorus was less than 3 mg·kg^-1, and the overall level was low. The comprehensive ranking of soil fertility were in descending order of M. macclurei forest, M. chapensis forest, Chinese fir forest, Castanopsis hystrix forest, Cinnamomum camphora forest, Mytilaria laosensis forest and Schima superba forest. It indicates that the soil fertility under the Chinese fir forest in this area is not lower than that of the broad-leaved forest. Taking appropriate measures can enhance its ecological and economic benefits.