柑橘园土壤·植株叶片及根的钙含量调查与分析

[目的]研究广西柑橘主产区耕层土壤、叶片和侧根中的钙含量现状及其之间的相关关系,为钙肥的合理施用提供理论参考。[方法]采集不同树龄的土壤、叶片和侧根样品,分析钙元素含量状况,并用SPSS软件进行统计分析。[结果]柑橘园土壤交换性钙含量范围为162~7 550 mg/kg,平均1 343 mg/kg,叶片钙含量范围为1.35%~5.29%,平均3.15%,侧根钙含量范围为0.45%~2.67%,平均1.28%;柑橘侧根钙含量随树龄的增长而增加,二者呈0.01水平显著的正相关关系,而果园耕作层土壤交换性钙、柑橘叶片钙含量与树龄之间相关性不显著,但与土壤pH的相关性在0.01水平显著;柑橘园耕作层土壤交换性钙、柑橘叶片及侧根钙的含量之间存在0.01水平显著的正相关关系。[结论]柑橘园土壤、叶片和侧根中的钙含量差异较大,大部分的土壤和叶片样品钙含量低于临界值。在柑橘生产中,应因地制宜合理施用钙肥。

Investigation and Analysis of Calcium Contents in Soil, Citrus Leaves, and Branch Roots of Citrus Orchards

[Objective] The status of calcium contents in soil,citrus leaves,branch roots,and the correlation among the calcium contents were studied to provide references for reasonable application of calcium fertilizer.[Method] Top soil samples,citrus leaf samples and citrus root samples were taken from citrus orchards with different ages.The status of calcium contents were determined and analyzed by SPSS software.[Result]The contents of available calcium in cultivation layer soil ranged from 162-7 550 mg/kg,with an average of 1 343 mg/kg,while those in leaves and roots changed from 1.35% to 5.29% and 0.45%to 2.67%,with an average of 3.15% and 1.28%,respectively.Regression analysis showed that calcium concentrations in roots had the strongest positive correlation with the orchard age.Calcium concentrations branch roots increased with the increase of the orchard age.However,soil available calcium and leaf calcium both showed no significant correlation with the orchard age,but had significant correlation with pH.The results also indicated the significant positive correlations existed among the contents of available calcium in cultivation layer soil,the contents of calcium in the citrus leaf and the citrus branch root.[Conclusion] There was a great difference among the contents of calcium in top soil,citrus leaf samples and citrus root and the contents of calcium in top soil sample and citrus leaf samples were mostly lower than the critical concentration of calcium.It was suggested that calcium fertilizer should be used reasonably in citrus orchards.