为了解黄土高原苹果园肥力状况，在大量调查研究的基础上，结合GIS采集苹果主产区黄陵县的304个苹果园的土壤和叶片样品，测定分析土壤有机质、全氮、速效氮、pH、速效磷、速效钾、CEC及有效铁、锰、铜、锌的含量和叶片全氮、全磷、全钾及微量元素的含量，并根据土壤和叶片相应的评价标准对其进行丰缺评价。结果表明：该地区土壤有机质含量很低，72% 的果园未达到绿色食品土壤肥力指标的正常值含量；土壤和叶片氮含量较低，磷和钾含量较高，其需肥顺序为氮>钾>磷；该地区微量元素含量较低，在以后的生产中需多施微肥。通过对土壤养分进行相关性分析，得知土壤有机质含量的提升有利于土壤中大量元素的有效养分增加。从土壤和叶片养分间的相关性分析得知，仅土壤钾和叶片钾呈负相关，而其余元素全部呈正相关，由此得出通过提升土壤中某元素的含量可以使得叶片中相应元素含量相应增加，而元素钾无此效应。

In order to understand the apple orchard soil fertility in Loess Plateau, this paper took the Huangling county which is one of the high apple yield areas as a representative example, collected the soil and leaf samples in 304 apple orchards, detected and analyzed soil organic matter, total nitrogen, available nitrogen, pH, available phosphorus, available potassium, CEC, effective trace-elements and the total nitrogen, phosphorus, potassium, copper, zinc, iron and manganese in leaves, evaluated the apple orchard fertility according to the corresponding evaluating standards. The results showed that soil organic matter contents in 72% of apple orchards was low. Nitrogen contents in soil and leaves were low while phosphorus and potassium contents were high. The need for fertilizers was in an order of Nitrogen>Potassium, phosphorus. The content of trace elements were low. Increasing soil organic matter content can increase the contents of soil available nutrients. The correlation between soil nutrients and leaf nutrients were positive but potassium was negative, which suggests fertilization can improve leaf nutrients except the potassium.

S158.3

陕西省黄陵县果业局横向经费(No.A304021308)