陕西省苹果园土壤肥力与施肥现状评估

为深入了解陕西省苹果园施肥现状及农户养分资源投入中存在的问题,提出解决对策,对2005—2009年测土配方施肥项目21个县的土壤数据和"3414"肥料实验数据以及农户抽样调查数据进行了统计分析,结果表明:陕西省苹果园土壤有机质、碱解氮、速效磷、速效钾含量分别为12.6 g·kg-1、56.9 mg·kg-1、18.0 mg·kg-1、151.6 mg·kg-1,与20世纪80年代相比,分别提高了17.8%、16.1%、168.7%、2.2%,说明土壤肥力状况得到了改善;苹果园化肥施用量由关中向陕北呈递减趋势,三个生态区施肥量均表现出氮肥偏高,磷、钾肥适中或偏低的现状,体现了农民普遍"重氮轻磷钾"的施肥习惯;全省苹果实际产量高低次序为关中灌区陕北高原渭北旱原;全省苹果园土壤养分盈亏状况总体上是氮、磷盈余,钾亏缺,氮素盈余196.5 kg·hm-2、磷素盈余205.5 kg·hm-2、钾素亏缺12 kg·hm-2,建议今后在苹果生产中适当增加钾肥的投入。

Evaluation on the situation of fertilization and soil fertility in apple fields in Shaanxi Province

In order to understand the current situation of fertilization and nutrients resource input problems for farm -ers in apple fields in Shaanxi Province ,and to put forward countermeasures to solving these problems ,household survey was used to evaluate the situation by collecting data from the project of soil testing and formulated fertilization from 2005 to 2009 .21 counties and 7141 households in total were included in this study .The results showed that the contents of soil organic matter ,available nitrogen ,available phosphorus and available potassium in Shaanxi were 12 .6 g·kg - 1 , 56 .9 mg·kg - 1 ,18 .0 mg·kg - 1 and 151 .6 mg·kg - 1 ,respectively .Compared with those in 1980s ,the indexes were in-creased by 17 .8% ,16 .1% ,168 .7% and 2 .2% ,respectively .This indicated that the situation of fertilization in apple fields had been improved .In addition ,the application rates of chemical fertilizer from the Guanzhong irrigated area to the Loess plateau area of northern Shaanxi had decreasing trends .Overall ,the current situation of household fertilization in apple fields in Shaanxi Province was that nitrogen fertilizer inputs were excessive ,phosphate and potassium fertilizer in-puts were reasonable or insufficient ,and the yields of apple field from the Guanzhong irrigated area to the Loess plateau area had decreasing trends .The nitrogen and phosphorus surplus in Shaanxi were 196 .5 kg·hm - 2 and 205 .5 kg·hm - 2 , respectively ,but the potassium deficiency was 12 kg·hm - 2 .Therefore ,increase of potassium fertilization should be con-cerned for households in Shaanxi Province .