恩施州耕地土壤剖面理化特征及养分分布变化规律

Physicochemical Characteristics and Nutrient Profile Distribution of Cultivated Lands in Enshi Prefecture

对恩施州利川市齐岳山蔬菜、汪营粮食、恩施市芭蕉茶叶基地等3个观测点土壤剖面的理化特征及养分分布规律进行了研究。3个观测点土壤容重在1.23～1.43 g/cm3之间,为壤土或砂壤土;电导率23.57～38.83μS/cm,无盐碱化;pH 4.22～6.61,偏酸性或强酸性;有机质12.97～52.88 g/kg、铵态氮16.09～31.72 mg/kg、有效磷1.59～185.56mg/kg、速效钾0～131.03 mg/kg;总硒0.30～1.32 mg/kg,有效硒0.02～0.23 mg/kg,属富硒土壤。剖面有效养分从表层到底层呈下降趋势,绝对系数R2在0.132 9～0.939 9之间,不同养分差异大,剖面间分布规律基本一致。该项研究是土壤质量长期监测的基础工作,目的是监测不同施肥方式对蔬菜、粮食、茶叶基地土壤质量变化的影响,为修复土壤、提高农产品质量提供参考。

The physicochemical characteristics and nutrient profile distribution of vegetable soil in Qiyue mountain, grain soil in Wangying of Lichuan City and tea soil in Bajiao of Enshi City were studied. For the three observed points, soil bulk density was between 1.23–1.43 g/cm3, texture was loam or sandy loam, conductivity was 23.57–38.83 μS/cm with no salinization, pH was 4.22–6.61 with slightly or strongly acidity, organic matter was 12.97–52.88 g/kg, ammonium nitrogen was 16.09–31.72 mg/kg, available phosphorus was 1.59–185.56 mg/kg, available potassium was 0–131.03 mg/kg, total selenium was 0.30–1.32 mg/kg and available selenium was 0.02–0.23 mg/kg with Se-enrichment. The available nutrients were decreased with the increase of soil depth with the correlation coefficient R2 of 0.132 9–0.939 9, great difference existed in different nutrients but with the similar profile distribution. The purpose of this study is to monitor the effects of different fertilization methods on soil quality changes in vegetable, grain and tea bases, and to lay a foundation for soil restoration and improvement of agricultural product quality.