不同海拔的大别山山核桃林地土壤性质和叶片营养元素分析

为了比较不同海拔大别山山核桃林地土壤性质和叶片营养元素的差异及相关性，为大别山山核桃林地科学施肥和养分管理提供参考，采用酸度计法、重铬酸钾容量法、半微量凯氏定氮法、碱解扩散法、盐酸氟化铵浸提-分光光度法和醋酸铵-火焰光度计法分别测定了不同海拔大别山山核桃林地0 ~ 30 cm土层pH、有机质、速效氮、速效磷、速效钾，采用原子吸收分光光度法测定了土壤和叶片的氮、磷、钾、钙、镁、锌含量，并进行显著性分析和相关性分析。结果表明：（1）不同海拔大别山山核桃林地土壤速效磷、全氮、全磷、全钾、钙、镁和锌含量存在显著性差异（P < 0.05），大别山山核桃叶片钾、钙和镁含量存在显著性差异（P < 0.05）。（2）不同海拔大别山山核桃林地土壤pH随着海拔升高而降低，而有机质和氮含量随着海拔升高而升高；叶片钾含量随海拔升高而升高，钙和镁含量则是随着海拔升高而降低，其余营养元素受海拔影响较小。（3）大别山山核桃叶片营养元素之间、土壤营养元素之间、以及叶片与土壤之间存在一定相关性，其中土壤间相关性达到显著水平的有2对，叶片间相关性达到显著水平的有4对，土壤和叶片间相关性达到显著水平的有2对（P < 0.05）。大别山山核桃林地土壤平均pH值为5.18，偏酸性；有机质含量均值为5.07%；速效氮、速效磷含量较高，速效钾较匮乏；微量元素平均含量依次为Mg>Ca>Zn。建议增施生石灰进行土壤改良，减少氮肥施用，增施磷钾肥，尤其是钾肥，将化学肥料和有机肥料混合增施，保持土壤养分平衡。

Analysis of soil properties and leaf nutrient elements in Carya dabieshanensis woodlands at different elevations of Dabieshan

In order to compare the differences and correlations of soil properties and leaf nutrients in woodlands of Carya dabieshanensis at different elevations of Dabieshan, and to provide references for scientific fertilization and nutrient management, the soil pH, organic matter, available N, available P and available K contents were determined by the acidity meter method, potassium dichromate volumetric method, semi-micro Kjeldahl method, alkaline diffusion method, ammonium fluoride hydrochloride leaching-spectrophotometric method and ammonium acetate-flame photometric method, respectively. The N, P, K, Ca, Mg and Zn contents in the soil and leaves were determined by atomic absorption spectrophotometry at different elevations of C. dabieshanensis woodlands, and significance and correlation analyses were performed. The results were: (1) There were significant differences (P < 0.05) in the contents of available P, TN, TP, TK, Ca, Mg and Zn in the soils of C. dabieshanensis woodlands at different elevations, and significant differences (P < 0.05) in the contents of K, Ca and Mg in the leaves of C. dabieshanensis. (2) Soil pH decreased with increasing the elevation, while the organic matter and N content increased with increasing elevation in C. dabieshanensis woodlands at different elevations. The K content of leaves increased with elevation, while the