重庆垫江柑橘园土壤和叶片养分状况分析

Research for nutrient status of citrus orchard soils and leaves in Dianjiang county,Chongqing city

为摸清重庆垫江柑橘园土壤和叶片营养元素状况,2019~2020年采集了重庆垫江柑橘主产区的118份土壤和130份叶片样品进行养分分析和相关性分析。结果表明:1)pH适宜的土样占94.45%,但是土壤有机质含量适宜的土样仅占33.33%;土壤大量元素碱解氮、有效磷和速效钾含量多数表现偏低,适宜的土壤分别占5.56%、16.67%和33.33%;中量元素交换性钙和交换性镁含量均表现为高量或过量;微量元素有效硼、有效铜、有效铁、有效锌和有效锰含量适宜的土壤分别占16.67%、38.89%、5.56%、27.78%和11.11%,有效锌含量缺乏和低量的样品占72.22%。2)在叶片营养中,大量元素氮、磷和钾含量适宜的样品占比分别为44.62%、53.08%和12.31%,钾表现为缺乏或偏低的样品比例达到87.70%;中量元素钙、镁和硫含量适宜的样品占比分别为68.46%、53.85%和94.61%,且缺乏和过量现象较少;微量元素铁、锰、锌、铜和硼含量适宜的样品占比分别为62.31%、46.15%、3.85%、36.92%和69.23%,锌和铜含量缺乏或低量的样品占比较高。3)土壤pH与有机质和有效养分含量之间存在一定的相关性,其中土壤pH与土壤有效铁、有效锰含量呈极显著负相关,土壤有机质与有效铜含量呈显著正相关;叶片各营养元素间存在一定的相关性,其与土壤营养元素之间也具有一定的相关性。4)不同柑橘品种影响叶片除钾和锌以外的营养元素含量,默科特叶片氮、镁、铁、锰和硼共5个元素的含量均为所有品种中最高。因此,重庆垫江柑橘园根据不同品种和养分情况施肥,注意在土壤中增施有机肥,适量补充氮肥、磷肥与钾肥以及微量元素硼、铜、铁、锌和锰,特别是锌,同时注重叶面适量补充大量元素钾和微量元素锌、锰和铜,为垫江乃至重庆柑橘高产优质和化肥减施增效提供依据。

In order to define the status of soil and leaf nutrient elements of citrus orchard in Dianjiang district,Chongqing city,118 soil and 130 leaf samples were collected from citrus orchards from 2019 to 2020 in Dianjiang,Chongqing for nutrient analysis and correlation analysis.The results indicated that,1)The soil samples accounted for 94.45%with suitable pH for citrus growth.There were only 33.33%of soil samples with suitable organic matters for citrus growth.In general,soil available nitrogen,available phosphorus and available potassium were deficient at large and only 5.56%,16.67%and 33.33%of soil samples were suitable,respectively.The exceeding proportions(high and excessive grades)of samples for available calcium and available magnesium were all 100%.Meanwhile,16.67%,38.89%,5.56%,27.78%and 11.11%of samples were suitable in available boron,available cuprum,available ferrum,available zinc and available manganese contents,respectively.The deficiency and low grades proportions of available zinc was 72.22%.2)In leaf nutrition,44.62%,53.08%and 12.31%of samples were suitable in nitrogen,phosphorus and potassium contents,respectively,especially the proportion of samples with insufficient(deficiency and low grades)potassium was reached to 87.70%.The proportion of soil samples with suitable calcium,magnesium and sulphur for citrus growth were 68.46%,53.85%and 94.61%,respectively,and there were fewer samples of deficiency and excessive grades.Meanwhile,62.31%,46.15%,3.85%,36.92%and 69.23%of samples were suitable in ferrum,magnesium,zinc,cuprum and boron contents,respectively.There were a little higher proportions of the deficiency and low grades samples of zinc and cuprum.3)There appeared some correlation between soil pH,soil organic matter and soil available nutrients.Among which,there existed significantly negative correlation between soil pH and soil available ferrum,manganese contents.And soil organic matters was significantly positively correlated with available cuprum.There were certain correlations among leaf nutrients,and which were also related to soil available nutrients.4)The contents of nutrient elements except potassium and zinc in leaves were affected by different citrus cultivars.The contents of nitrogen,magnesium,ferrum,manganese and boron in leaves of Murccot were the highest among all citrus varieties.Therefore,the fertilizer scheme of citrus orchard in Dianjiang,Chongqing city should be made according to different varieties and nutrient conditions.Furthermore,it should be paid more attentions to the increase of organic fertilizer.It was also needed to keep appropriate supplementary application of nitrogen,phosphorus,potassium,boron,cuprum,ferrum,zinc and manganese fertilizers,particularly zinc application in soil.At the same time,the foliar supplement of mass element potassium and trace element zinc,manganese and cuprum,which provides the reference for the high yield and quality of citrus as well as reducing chemical fertilizers application and efficiency improvement in Dianjiang or even in Chongqing city.