贵州喀斯特山区不同海拔花椒人工林土壤质量评价

阐明贵州喀斯特山区花椒人工林的土壤养分含量及其质量综合指数至关重要。以不同海拔样地的土壤为研究对象,采用土壤农业化学、环境矿物学技术对矿质元素等进行分析。结果表明:不同样地土壤的pH值呈显著差异,随海拔增加表现为升高—降低的变化趋势;最低海拔(594m,HJ1)与最高海拔(884m,HJ5)样地的土壤有机碳、总氮、速效氮总体显著高于中间3个海拔样地(660m、705m、778m,HJ2—HJ4),总磷与速效磷的变化则相反;除大量元素外,矿质元素在不同海拔花椒林地之间变化规律不明显,其中总硫、铅、镉、硒等元素表现为最高海拔样地急剧升高的趋势;氮、磷与其他矿质元素之间表现出一定的显著性相关,表明其关系密切;土壤质量综合指数为HJ5(2.16)HJ3(0.43)HJ4(0.19)HJ1(-0.21)HJ2(-2.60),表明高海拔花椒林地表层土壤质量总体优于低海拔,揭示了土壤养分随海拔变化表现出分异规律。土壤管理上应同时施用有机肥和矿质元素肥料,提高土壤养分供给能力和利用效率。以上结论可为贵州喀斯特山区花椒林养分管理和可持续经营工作提供借鉴和参考。

Evaluation of soil quality of Chinese prickly ash artificial orchard at different altitudes in Guizhou karst mountainous area

We examined the soil nutrient content of a Chinese prickly ash artificial orchard in the Guizhou karst mountainous area; its comprehensive quality index is of great significance. In this study, soils at different altitudes have been collected from Guizhou karst mountainous area and samples were analyzed by using techniques of agricultural soil chemistry and environmental mineralogy. The study results indicated that the pH values of soils at different altitudes had significant differences, with a trend of increasing-decreasing with increased altitude; the soil organic carbon, total nitrogen, and available nitrogen of soil in the sample plots at the lowest altitude (594 m, HJ1) and the highest altitude (884 m, HJ5) were all significantly higher than those of the three sample plots at the middle altitudes (660 m, 705 m, 778 m, HJ2-HJ4), while the trend in the total phosphorus was exactly opposite to that of the available phosphorus. However, there is no significant differences among concentrations of mineral elements in the Chinese prickly ash orchards at different altitudes was not obvious; the contents of total sulfur, lead, cadmium, and selenium with the highest altitude have been determined. There were significant correlations among nitrogen, phosphorus, and other mineral elements, suggesting a close relationship. The soil quality comprehensive index was HJ5 (2.16) > HJ3 (0.43) > HJ4 (0.19) > HJ1 (-0.21) > HJ2 (-2.60), suggesting that the surface soil quality of Chinese prickly ash orchard at high altitudes is better than that at low altitudes, comprehensively speaking, revealing that soil nutrient content changed along with the change in altitude. As a result, it is suggesting that organic fertilizer and mineral element fertilizer could be used simultaneously to improve the soil nutrient supply capacity and utilization efficiency. This study could be helpful for the nutrient management and sustainable management of Chinese prickly ash orchards in the Guizhou karst mountainous area.