延长县2018年治沟造地项目新增耕地土壤养分特征分析

Analysis of soil nutrient characteristics in newly-increased farmlands of gully land consolidation project of 2018 in Yanchang County

通过对陕西省延安市延长县2018年治沟造地项目新增耕地土壤养分含量分析,以全国第二次土壤普查养分分级标准为依据,研究新增耕地土壤养分特征,探讨提升新增耕地土壤养分及加强其土地生产力的措施。结果表明,土壤pH整体呈现弱碱性至碱性;土壤有效磷(AP)和有机质(OM)含量偏低,处于4~5级水平;土壤速效钾(AK)和全氮(TN)含量极低,处于5~6级水平。从地域分布来看,黑家堡镇土壤pH较雷赤镇显著高5.41%,整体呈现西北部高于东南部的趋势;安沟镇土壤AP和TN较黑家堡镇分别高16.35%和21.87%,整体呈现中南部高于西北部和东南部的趋势;雷赤镇土壤AK较郑庄镇显著高55.92%,整体上呈现东南部高于西部的趋势。通过相关性分析可知,除AP与TN之间存在极显著相关(p<0.01)之外,pH、OM、TN、AP和AK之间均无明显的相关关系,养分协调性极差。因此,建议在新增耕地施肥上适当增加偏酸性肥料和氮磷复合肥料的施用量,在种植方式上通过种植绿肥作物逐渐改善土壤养分协调性,以全面调解土壤养分状况。

Based on the analysis of the soil nutrient content of the newly-increased farmland in gully land consolidation project of Yanchang County,Yan’an city,Shaanxi province in 2018,and based on the nutrient classification standards of the second national soil census,the soil nutrient characteristics of the newly-increased farmland were studied and measured to increase soil nutrients and strengthen land productivity were discussed.The results showed that the soil pH was weakly alkaline to alkaline as a whole;Soil available phosphorus(AP)and organic matter(OM)were low,at level of 4~5;Soil available potassium(AK)and total nitrogen(TN)were extremely low,at the level of 5~6.In terms of geographical distribution,the soil pH of Heijiapu Town was significantly higher than that of Leichi Town by 5.41%,showing a trend higher in the northwest than southeast.The AP and TN in Angou Town were higher than that in Heijiapu Town,respectively by 16.35%and 21.87%,the overall trend is higher in the central-southern than northwest and southeast;The soil AK in Leichi Town is significantly higher than Zhengzhuang Town by 55.92%,and the overall trend is higher in the southeast than west.Correlation analysis showed that there was no significant correlation between pH,OM,TN,AP and AK except for the significant correlation between AP and TN(p<0.01),and the soil nutrient coordination was poor.Therefore,in order to fully adjust the soil nutrient situation,it is recommended to appropriately increase the application of partial acid fertilizers and nitrogen and phosphorus review fertilizers,and gradually improve the soil nutrient coordination by planting green manure crops on newly-added farmland.