典型石漠化植被恢复区土壤理化特征及多指标聚类研究

Physicochemical Properties and Multi-Indicator Clustering of Soils in Typical Rocky Desertification Vegetation Restoration Area

为揭示造林20年后不同石漠化恢复模式对土壤结构和理化性质的影响,以滇中地区7种恢复模式下样地土壤为研究对象,研究不同石漠化恢复模式下土壤理化性质分布特征并进行多指标聚类分析。结果表明:除油杉林外,其他样地土壤养分等级均为中高级;土壤颗粒组成较为合理,分形程度较好,抵抗侵蚀的能力较强;不同恢复类型对石漠化土壤的改良存在明显不同,混交林明显优于纯林;由于受土壤母质、地形以及水文等因素的影响,相同恢复类型间存在差异,华山松林和油杉林总体较差;研究区土壤可蚀性因子K值与粉粒含量呈正向变化特征;对土壤理化性质进行Q型聚类可以将受试样地土壤分为4类,油杉林和华山松林被单独分出。研究结果可为地方政府制定科学合理的喀斯特石漠化地区生态防治措施提供理论基础和技术支撑。

In order to reveal the influence of different rocky desertification restoration modes on soil structure and physicochemical properties after 20 years of afforestation,the distribution characteristics of soil physicochemical properties under seven rocky desertification restoration modes in central Yunnan Province were studied and multi-index clustering were conducted.The results showed that,except for Keteleeria fortunei,the soil nutrient grade of the other plots were medium and high level;the soil particle composition was more reasonable,the degree of fractal was better,and the resistance to erosion was stronger.The different types of vegetation restoration had obviously different effects on the improvement of rocky desertification soils,and mixed forests were significantly better than pure forests.Due to the influences of soil parent material,topography,and hydrology,there were differences among the same restoration types,the Pinus armandii Franch.and Keteleeria fortunei;were generally poor.The soil erodibility factor K in the study area was characterized by positive variation in relation to the content of powder particles.The Q-clustering of soil physicochemical properties could classify the sample soils into four categories,and Keteleeria fortunei and Pinus armandii Franch.were separated out separately.The results of this research could provide theoretical basis and technical support for the local government to formulate scientific and reasonable ecological prevention and control measures of karst rocky desertification.