勐海县茶园土壤养分状况及肥力质量评价

Soil nutrient status and fertility evaluation of tea gardens in Menghai County

勐海是云南省产茶大县,深入了解全县茶园土壤养分状况与肥力水平,可为勐海县茶园土壤改良与精准施肥提供科学依据。本研究对勐海县茶园面积集中的6个乡镇进行实地调查和布点采样,分析了151个茶园土壤pH、有机质及大量营养元素的含量,并采用模糊数学隶属度函数模型,计算土壤肥力综合指数(IFI),进而对勐海县茶园土壤养分状况进行数值化综合评价。结果表明,勐海县各乡镇茶园pH为3.83~6.16,大部分土壤pH适合茶树生长。茶园土壤有机质含量范围在20.88~101.80 g·kg^-1之间,有机质含量比较丰富,均达到Ⅰ级标准。勐海县各乡镇茶园全氮、全磷和全钾含量较高,但碱解氮和有效磷含量不足。除勐混镇外,其他各乡镇达到优质高产茶园土壤碱解氮含量的比例低于30%。速效钾供应充足,仅勐阿镇和勐混镇分别有6.25%和20.00%土壤速效钾处于Ⅲ级标准。勐海县各乡镇茶园土壤肥力综合指数为0.30~0.84,勐阿镇、勐遮镇、格朗和乡和布朗山乡有部分茶园土壤达到Ⅰ级和Ⅱ级标准,茶园土壤肥力等级主要分布在Ⅲ级和Ⅳ级,除布朗山乡外,其余各乡镇茶园土壤肥力处于中低水平的比例超过60%。研究表明,勐海县茶园大部分土壤pH适合茶树的生长,土壤有机质、全氮、全磷、全钾及速效钾含量丰富,而碱解氮和有效磷含量不足,需要有针对性地调整施肥策略。

Menghai is a large tea-producing county in Yunnan Province.In order to provide a scientific basis for soil improvement and precise fertilization,we studied the soil nutrient status and fertility level of tea gardens in Menghai County.In this study,soil samples from 151 tea gardens was analyzed in terms of pH,organic matter content,and nutrient elements,through field investigation and spot sampling in six towns within an area of concentrated tea gardens in Menghai County.The integrated fertility index(IFI)was also calculated to evaluate the soil nutrient status of the tea plantations.The pH of tea garden soil varied from 3.83 to 6.16,with most soil pH suitable for the growth of tea trees.The organic matter contents ranged from 20.88 g·kg^-1 to 101.80 g·kg^-1 and the content of organic matter was rich,reaching gradeⅠstandard.The total nitrogen,total phosphorus,and total potassium contents in Menghai County tea gardens were high,but the supply of available nitrogen and available phosphorus were insufficient.The available potassium supply was sufficient,with only Meng′a and Menghun towns having soil with available potassium lower than the gradeⅢstandard(6.25%and 20.00%,respectively).The integrated fertility index varied from 0.30 to 0.84,and some tea garden soils in Meng′a,Mengzhe,Gelanghe,and Bulangshan townships met the standards of gradeⅠor gradeⅡ.However,the soil fertility of tea gardens in the villages and towns fell mainly in the gradeⅢorgradeⅣcategories.More than 60%of tea gardens had low or medium soil fertility levels,except for the Bulangshan townships.The soil pH levels of tea gardens in Menghai County are suitable for the growth of tea trees.The contents of organic matter,total nitrogen,total phosphorus,total potassium,and available potassium in these soils are high,but the supply of available nitrogen and available phosphorus is insufficient.This highlights the need for suitable fertilization schemes.