陕西省苹果施肥状况评价

为了解陕西省苹果施肥现状及农户养分资源投入中存在的问题,提出解决问题的对策.对测土配方施肥项目2005～2009年的21个县7141户调查数据进行了分析和评价.结果表明,陕北高原、渭北旱塬和关中灌区有机肥施用农户分别占到99.96％、24.52％和20.37％,全省平均50.15％;化肥氮、磷、钾施用量从陕北高原、渭北旱塬到关中灌区均呈增加趋势,其中氮肥(N)由490 kg/hm2增加到619 kg/hm2,磷肥(RO5)由318 kg/hm2增加到447 kg/hm2,钾肥(K2O)由73 kg/hm2增加到382 kg/hm2.各区域苹果化肥氮磷钾和有机肥施用量整体上与产量都有显著的相关性,且化肥和有机肥养分投入均表现出报酬递减趋势.陕北高原、渭北旱塬和关中灌区化学氮肥施用适量农户分别占18％、17％和12％,全省平均17％,过量农户分别占67％、74％和78％,全省平均72％；磷肥施用适量农户分别占12％、27％和15％,全省平均20％,过量农户分别占42％、52％和65％,全省平均50％;钾肥施用适量农户分别占11％、12％和14％,全省平均12％,不足农户分别占84％、48％和15％,全省平均56％.陕西省农户苹果施肥中存在的问题为氮肥投入过量、磷肥投入过量和不足并存、钾肥和有机肥投入不足.因此,增加有机肥投入,大幅度降低氮肥投入和合理施用磷肥是今后陕西省果农施肥的重点.另外,在陕北高原和渭北旱塬要注重增施钾肥.

Evaluation of the situation of fertilization in apple fields in Shaanxi province

In order to understand the current situation of fertilization and nutrients resource input problems of farmers in apple fields in Shaanxi province, and to put forward countermeasures to solve the problems, we used household survey data, which collected from the project of soil testing and formulated fertilization from 2005 to 2009, to evaluate the situation. There were totally 21 counties and 7141 households. The results show that the ratios of households who used organic manure in the Loess plateau area of northern Shaanxi, the Weibei tablelands and the Guanzhong irrigated area are 99.96%, 24.52% and 20.37% respectively, and the averaged ratio in the whole province is 50.15%. The application rates of chemical fertilizer NPK from the Loess plateau area of northern Shaanxi to the Guanzhong irrigated area have increasing trends, and the amounts of nitrogen fertilizer are from 490 to 619 kg/ha, the amounts of phosphate fertilizer are from 318 to 447 kg/ha and the amounts of potassium fertilizer are from 73 to 382 kg/ha. On the whole, the chemical fertilizer NPK rates and organic manure rates have very significant correlations with the yield in all regions, and the fertilizer and organic manure inputs show diminishing return trends. Compared with the levels of fertilizer rates, in the Loess plateau area of northern Shaanxi, the Weibei tablelands and the Guanzhong irrigated area, for chemical N application, 18%, 17% and 12% are rational respectively and the average of the whole province is 17%, and 67%, 74% and 78% are excessive and the average of the whole province is 72%; for chemical P2O5 application, 12%, 27% and 15% are rational and the average of the whole province is 20%, and 42%, 52% and 65% are excessive and the average of the whole province is 50%; for chemical K₂O application, 11%, 12% and 14% are rational and the average of the whole province is 12%, and 84%, 48% and 15% are insufficient and the average of the whole province is 56%. The current situation of household fertilization in apple fields in Shaanxi province is that nitrogen fertilizer inputs are excessive, phosphate fertilizer inputs are both excessive and insufficient, and potassium fertilizer and organic manure inputs are both insufficient. Therefore, increasing organic manure inputs, significantly reducing nitrogen fertilizer inputs and reasonable application of phosphate fertilizer should be concerned for households in Shaanxi province. In addition, increasing potassium fertilizer inputs in the Loess plateau area of northern Shaanxi and the Weibei tablelands.