三峡重庆库区柑橘园土壤养分丰缺状况研究

Status of soil fertility in citrus orchards of Chongqing Sanxia Reservoir Area

采集了三峡重庆库区柑橘主产区459个果园0—30 cm的土壤样品进行取样分析。结果表明,库区有78.7%柑橘园土壤pH值适合柑橘生长;有60.3%的柑橘园土壤有机质含量偏低。土壤速效氮和磷缺乏,分别占到72.4%和41.7%,土壤速效钾缺乏和过量并存。库区柑橘园缺乏有效B、Zn、Fe、Mn的比例分别为86.3%、37.9%、27.0%、20.3%;土壤有效Fe、Mn和Cu含量在部分果园存在过量现象,分别占柑橘园的52.5%、36.4%和26.4%。因此,该区柑橘生产要因地制宜,建议在柑橘园增施B、Zn肥,石灰和其它碱性肥料,同时减少喷施含Cu杀菌剂。

Knowing soil nutrient fertility status is a basis to formulate a suitable fertilization strategy.Top soil（0-30 cm）samples collected from 459 citrus orchards in Chongqing Sanxia Reservoir Area were tested and classified in present study.The results showed that the soil pH of 78.7% orchards was suitable for citrus growth,soil organic matter of 60.3% orchards were low,and the deficiency rate of available macro-nutrients N and P was 72.4% and 41.7%,respectively,while soil available K were high in some orchards.The deficiency rate of available B,Zn,Fe and Mn was 86.3%,37.9%,27.0% and 20.3%,respectively.The results also indicated that amounts of citrus soils which have excessive available Fe,Mn and Cu accounted for 52.5%,36.4% and 26.4% of total citrus orchards.Therefore,it was suggested that more B,Zn,lime or other alkaline fertilizer and less Cu fungicide should be used in the tested citrus orchards.