南方红壤侵蚀区不同植被恢复年限下芒萁叶功能性状对土壤因子的响应

Response of functional traits of Dicranopteris dichotoma leaves to soil factors in different vegetation restoration years in red soil erosion area of Southern China

目前关于我国南方红壤侵蚀区生态恢复植被-芒萁(Dicranopteris dichotoma)功能性状(Functional Traits)的研究鲜有报道。以该区域不同植被恢复年限下(包含0年未恢复地、6年、12年、18年、36年以及80年的次生林地)芒萁叶功能性状为研究对象,结合不同植被恢复年限下土壤因子的变化,采用样方调查分析法,探讨随植被恢复年限的增长芒萁叶功能性状的变化规律及其相互关系,以及芒萁叶功能性状对土壤因子的响应。结果表明,芒萁叶功能性状各指标随着植被恢复年限的增加变化差异明显(P<0.05),并随植被恢复年限的增长表现出胁迫型、扩展型、竞争型不同功能性状组合;芒萁叶功能性状间的相关性也表现出显著的特征(P<0.01);主成分分析(Principal Component Analysis, PCA)表明叶全氮含量、比叶面积和叶全磷含量主成分贡献排名高,可作为芒萁叶功能性状评价的主要指标。通过冗余分析(Redundancy Analysis, RDA)发现,土壤全碳含量、土壤全氮含量、土壤全磷含量对芒萁叶功能性状各项指标影响显著(P<0.01)。芒萁伴随着植被恢复年限的增长,叶功能性状表现出不同的组合状况,且受土壤因子变化表现出相应的适应策略,反映了芒萁叶片随土壤因子变化形态可塑性强,作为重要的生态恢复植被有利于南方红壤侵蚀区植被的有效建植与恢复。

At present, there are few reports on the ecological restoration vegetation of the red soil erosion area in southern China. In this study, the functional traits of Dicranopteris dichotoma were studied under different vegetation restoration years in the region(including non-recovered land, 6 years, 12 years, 18 years, 36 years, and 80 years), combined with different vegetation restoration years. Changes of soil factors were studied to investigate the changes of the functional traits of the leaves and the relationship between the functional traits of the leaves and the response to the soil factors. The results showed that the functional traits of the leaves were significantly different with the increase of vegetation restoration years(P<0.05), and showed the combination of different functional traits of stress, expansion and competition with the increase of vegetation recovery years. The correlation between leaf functional traits also showed significant characteristics(P<0.01). The principal component analysis showed that the total nitrogen content, specific leaf area and total phosphorus content of leaves were ranked high, which could be used as the main evaluation index of functional traits of the leaves. Through redundant analysis(P<0.01), soil total carbon content, soil total nitrogen content, and soil total phosphorus content had significant effects on the functional traits of the leaves of Dicranopteris dichotoma(P<0.01). With the growth of vegetation restoration years, leaf functional traits showed different combinations, and corresponding adaptation strategies by soil factors which reflected the strong plasticity of the leaves of Dicranopteris dichotoma with soil factors, as an important ecological restoration. Vegetation is conducive to the effective establishment and restoration of vegetation in the red soil erosion area of southern China.