贵州喀斯特山区花椒林小生境的土壤质量特征

Soil Quality Characteristics of Different Micro-Habitat in Zanthoxylum bungeamun Forest of Guizhou Karst Areas

【目的】探明不同小生境土壤性质的空间变化特征,弄清其土壤养分的变化规律,为花椒种植的合理布局提供科学依据,以促进喀斯特地区石漠化的生态恢复。【方法】选择贵州喀斯特山区花椒林内石槽、土面、石沟、石缝和石坑5种小生境为研究对象,采用单因素方差分析及主成分分析等方法研究花椒林下不同小生境0～20 cm土层不同矿质元素对土壤质量的影响。【结果】石槽、石缝、石沟小生境的土壤pH显著高于石坑和土面;土面、石槽小生境土壤的碳、氮、磷元素含量较高,石坑、石沟则较低;中量、微量矿质元素在不同小生境土壤间变化较小;土壤有机碳、速效氮、速效磷与其他矿质元素间的相关性显著,存在相互制约的关系;土壤质量优劣依次为土面(0. 73)、石槽(0. 49)、石缝(-0. 01)、石坑(-0. 46)和石沟(-0. 75)。【结论】矿质元素对土壤质量的影响均较大,将中量、微量矿质元素纳入土壤质量评价指标体系具有合理性;土面、石槽、石缝土壤可加以改造利用,石洞、石沟土壤以自然恢复为主。

[ Objective] The pusent paper aims to explore the spatial variation characters of soil property in micro-habitat, and the variation regulation of soil nutrients, thus to provide scientific basis for rational layout of Z. bungeamun plantation, so as to promote the ecological re- covery of rock desertification in karst area. [ Method] Taking five kinds of micro habitats, including stone trough, earth surface, stone groove, stone seam and stone pit, as the research objects in Guizhou karst mountainous area, ANOVA and principal component analysis were conducted to explore the influence of 0 - 20 cm soil layer in different micro-habitats of Z. bungeamuu forest on soil quality. [ Result] Soil pH in stone trough, stone seam and stone groove were significantly higher than stone pit and earth surface ; Earth surface and stone trough were of higher contents of carbon, nitrogen and phosphorus, while that in stone pit and stone groove were lower ; medium and trace mineral ele- ments varied little among various micro-habitats ; soil organic carbon, available nitrogen and available phosphorus and significantly correlated with other mineral elements, with mutual restraints ; Soil quality followed the sequence of earth surface （0.73） 〉 stone trough （0.49） 〉 stone seam（ - 0.01 ） 〉 stone pit （ - 0.46） 〉 stone groove （ - 0.75 ）. [ Conclusion ] Mineral elements affect soil quality greatly, so it was ra- tional to absorb medium and trace mineral elements into soil quality assessment indicator system; Earth surface, stone trough and stone seam could be transformed and utilized, while stone pit and stone groove should be in natural recovery.