红壤砂糖橘果园土壤和叶片养分状况研究

Study on Nutrient Status of Soil and Leaves in “Shatangju” Orchards in Red Earth Region

摘要: 为掌握广东省砂糖橘产区果园的营养状况，实现砂糖橘的优质高产。2015和2016年共采集土壤和叶片样品各130份进行检测并做相关性分析。广东省砂糖橘果园强酸性土壤占比68.46%，pH平均值4.52，土壤整体偏酸；有机质平均含量18.06 g/kg处于适量水平；有效锌和有效硼含量处于适量范围的比例分别为53.85%和42.31%；碱解氮、速效钾低于适量范围的土样分别占比76.16%、56.15%；交换性钙和交换性镁处于极缺范围的土样占比分别为52.31%、93.08%，另有55.38%的土样有效磷处于高量水平；叶片中磷、钾和硼处于适量范围的比例分别为40.77%、79.23%和81.54%；氮元素含量偏低，83.08%的叶样低于适量水平；钙、镁和锌则缺乏严重，处于极缺范围的叶样分别占比48.46%、51.54%和78.46%。相关性分析显示砂糖橘叶片各矿质元素之间以及土壤养分与叶片矿质元素之间存在一定的相关性。广东省砂糖橘果园土壤和叶片钙、镁大量不足，且叶片缺锌最为严重，生产中应注意结合土壤和叶片营养诊断的结果补充土壤钙、镁肥，同时喷施叶面锌肥，调整土壤pH，科学施肥以满足砂糖橘生长的需要。

Abstract: In order to master the nutritional status of “Shatangju” orchards in Guangdong province, 130 sam-ples of soil and leaves were collected in 2015 and 2016 for test and correlation analysis. The results showed that the overall soil was acid and 68.7% of soil sample was strongly acidic with average pH 4.52. The content of soil organic matter was 18.06 g/kg at suitable level. The content of available Zn and B in the optimum level account for 53.44% and 42.31%, respectively. The available N and K were at lower level and the proportions of soil sample below optimum were 76.16% and 56.15%, respectively. The exchange Ca and Mg were in serious shortage in most soil samples and the proportions in extreme deficiency status were 52.31% and 93.08%, respectively. The available P was at higher level with 55.38% of soil sample. The contents of P, K and B in the leaves were at optimum level with 40.77%, 79.23% and 81.54% leaf sample, respectively. The content of N element was at lower level, accounting for 83.08% of leaf sample. The proportions of leave Ca, Mg and Zn in extreme deficiency status were 48.46%, 51.54% and 78.46%. The correlation analysis showed that there was a certain correlation among the leaf mineral elements or between soil nutrients and the miner-al elements of the leaf. In conclusion, the contents of Ca and Mg in “Shatangju” orchards of Guang-dong province were largely insufficient, and Zn deficiency was the most serious in leaf. In practical production, the supplying of soil Ca and Mg and spraying of Zn foliar fertilizer are applied with paying attention to the results of soil and leaf nutrition diagnosis, together with adjusting soil pH, to meet the need of “Shatangju” growth.