不同植被对广西石漠化地区土壤有机质的影响

为了客观评价不同植被在石漠化生态恢复中的作用,以便为先锋物种的选择提供理论依据.作者在大量野外调查和试验研究的基础上,利用数理统计方法,对广西石漠化地区不同植被恢复样地土壤有机质含量及其与其他土壤肥力因子的相关性进行了比较分析.结果表明:不同植被及恢复模式对土壤有机质含量影响的效果不同,植被类型与土壤有机质含量的相关性极为显著.乡土物种在石漠化生态恢复过程中具有极重要的作用,青檀样地土壤有机质含量明显高于原始森林及其他样地,侧柏、任豆、青冈、黄荆等乡土树种样地土壤有机质含量也高于外来物种湿地松和桉树样地.随着恢复年限的增加,土壤有机质含量有增加的趋势,但恢复50年后的森林样地土壤有机质含量却稍有下降.石漠化治理必须合理配置物种,重视乡土植物,充分考虑生态经济效益.

Influence of Different Vegetation on Soil Organic Matter Content in Karst Rocky Desertification Region, Guangxi Province

Taking experimental and mathematical statistics method, the soil organic matter content (SOM) and relevance between SOM and other soil fertility factors were comparative analysis. The result showed that the influence of different vegetation and different restoration patterns on SOM content are different, the relevance of vegetation types and SOM content is extremely significant. Native species play a very important role in eco-restoration of karst rocky desertification. The SOM content of the plots which dominant species is Pteroceltis tatarinowii are obviously higher than that of the primeval forest and any other plots. The SOM content of other native trees, such as Platycladus orientalis, Zenia insignis, Cyclobalanopsis glauca, Vitex negundo, etc. plots are higher than that of the alien species, such as Pinus eliottii, Eucalyptus robusta plots. With the recover time increase, the SOM content also has the increase trend. But, after 50 years, the SOM content of the primeval forest plots decreased slightly. Base on the analysis related, some suggestion, such as rational allocating species, pay attention to local plants, full account of eco-economic benefits in karst rocky desertification management, etc. were put forward by the authors.