不同地貌形态下植物地境结构特征研究——以河南省南太行地区为例

Research on the structural characteristics of underground plant habitat in different geomorphic forms:a case study of the south Taihang region in Henan Province

【目的】通过调查南太行丘陵与山地区域植物地境中不同层片植物根群结构、土壤肥力,探究不同地貌形态下植物地境结构特征的差异,为南太行地区的生态修复提供理论依据。【方法】采用植物样方调查及植物地境调查,记录不同地貌形态下植物的各项指标,统计地境剖面植物根群分布,测试地境剖面各土层有机质、水解性氮、有效磷、速效钾、含水量等土壤肥分指示性因子的含量。【结果】丘陵区域地下0~30 cm为草本植物根群圈,30~60 cm为灌木植物根群圈,60~100 cm为乔木植物根群圈;山地区域地下0~20 cm为草本植物根群圈,20~40 cm为灌木植物根群圈,40~70 cm为乔木植物根群圈。植物根系数量和土壤肥力随土壤深度增加呈下降趋势,山地区域土壤肥力空间异质性属于中等变异,丘陵区域不同土层土壤肥力空间异质性不同,属于中等变异或强变异,植物根系空间异质性均属于中等变异。丘陵区域地下30、60 cm左右植物根系的空间异质性出现拐点,山地区域地下20、40 cm左右植物根系的空间异质性出现拐点。【结论】乔灌草植物根系占据不同的地境空间,植物根群圈与土壤肥力对应层片具有较好的相关性。在地境剖面垂向上,植物根系空间异质性出现拐点的位置与植物根群圈位置具有相关性。不同地貌形态的土壤资源异质性对一年生草本植物根系影响显著。土壤中有效磷含量极度缺乏,生态修复时应注意补充土壤磷肥的含量,根据优势种与亚优势种合理选择植物,本研究可对南太行地区生态修复提供理论依据。

【Objective】In this study,the structure of plant root groups and soil fertility in different layers of plant habitat in the hilly and mountainous areas of south Taihang were investigated to explore the different characteristics of plant habitat structure under different geomorphic forms,so as to provide a theoretical basis for ecological restoration in the south Taihang region.【Method】Plant quadrat survey and plant habitat survey were used to record the plant indexes and the distribution of plant root groups in different geomorphological profiles.The content of indicative factors of soil fertility in each soil layer of the environmental profile was tested,including organic matter,hydrolyzable nitrogen,available phosphorus,available potassium and water content.【Result】In the hilly area,the 0-30 cm soil layer was the herb root group circle,the 30-60 cm layer was the shrub root group circle,and the 60-100 cm layer was the arbor root group circle.In the mountainous area,the 0-20 cm layer was the herb root group circle,the 20-40 cm layer was the shrub root group circle,and the 40-70 cm layer was the arbor root group circle.The number of plant roots and soil fertility decreased with the increase in soil depth.The spatial heterogeneity of soil fertility in the mountainous area belonged to medium variation,the spatial heterogeneity of soil fertility in different soil layers in the hilly area was different,belonging to medium variation or strong variation,and the spatial heterogeneity of plant roots belonged to medium variation.The spatial heterogeneity of soil fertility in different soil layers was different in the hilly area,which belonged to moderate variation or strong variation.The spatial heterogeneity of plant roots was in moderate variation.There was an inflection point in the spatial heterogeneity of plant roots of the layers of 30 and 60 cm in the hilly area,and the layers of 20 and 40 cm in the mountainous area.【Conclusion】The roots of trees,shrubs and grasses occupy different geographical spaces,and there is a good correlation between the plant root group circle and the corresponding layer of soil fertility.In the vertical direction of the landscape profile,the inflection point of the spatial heterogeneity of plant roots is related to the position of the plant root circle.The heterogeneity of soil resources in different geomorphic forms has a significant impact on the roots of annual herbs.In addition,the content of available phosphorus in soil is extremely scarce.During ecological restoration,attention should be paid to supplementing the content of soil phosphorus fertilizers,and plants should be reasonably selected according to dominant species and sub-dominant species.This study can provide a theoretical basis for ecological restoration in the south Taihang areas.