菜园土肥力特征及蔬菜硝酸盐污染的控制技术Ⅰ.长沙市郊专业蔬菜基地土壤磷素状况及无机磷形态的分级

来源 :湖南农业大学学报(自然科学版) | 被引量 : 0次 | 上传用户:hxz22
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为探明长沙市郊蔬菜基地菜园土磷素状况及土壤供磷水平,采用野外取样调查和室内分析相结合,对两种主要母质发育的菜园土耕作层和剖面分层样品进行了研究.结果表明,1)长沙市郊几个蔬菜基地土壤全磷和有效磷含量均较高,全磷含量0.78~2.72 g/kg,平均1.72 g/kg,有效磷12.82~286.7 mg/kg,平均156.7 mg/kg;2)土壤磷以无机磷形态为主,其变动范围为584.7~2 607.5 m g/kg,平均1 495.7 mg/kg,占全磷量的74.96%~95.86%,均显著高于其他农业土壤和自然土壤,是菜园土的一大显著肥力特征;3)土壤无机磷组成因成土母质不同而不同,第四纪红土母质发育的菜园土O-P含量最高,其次是Fe-P,Al-P较少,而由河流冲积母质发育的菜园土Fe-P含量最高,其次是Al-P和O-P;4)无机磷是土壤有效磷的主要来源,Ca2-P,Ca8-P,Al-P和Fe-P均与土壤有效磷呈极显著正相关. In order to find out the status of phosphorus and phosphorus supply in vegetable garden soils in suburbs of Changsha City, two kinds of vegetable cultivation layers and profile stratified samples with different parent materials were studied by field sampling and indoor analysis. 1) The contents of total phosphorus and available phosphorus in soils of several vegetable bases in the suburbs of Changsha were higher than those in other areas. The total phosphorus content was 0.78-2.72 g / kg with an average of 1.72 g / kg and available phosphorus was 12.82-28.67 mg / kg with an average of 156.7 mg / kg ; 2) Soil phosphorus is mainly in the form of inorganic phosphorus, with the range of 584.7 ~ 2 607.5 mg / kg, an average of 1 495.7 mg / kg, accounting for 74.96% ~ 95.86% of total phosphorus, which are significantly higher than other agricultural soils Natural soil is a significant fertility characteristic of vegetable garden soil. 3) The composition of inorganic phosphorus in soil is different due to different parent materials, and OP content of the garden soil with Quaternary red clay parent material is the highest, followed by Fe-P and Al-P Fe-P content was the highest in vegetable garden soil developed by alluvial parent material, followed by Al-P and OP; 4) Inorganic phosphorus was the main source of soil available phosphorus, Ca2-P, Ca8-P, Al-P and Fe -P were significantly and positively correlated with soil available phosphorus.
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