宁波市耕地有效硅含量及其影响因素

分析了宁波市9个县(市、区)的747个土壤样品的有效硅含量,并探讨了土地利用方式、土壤类型、地貌类型及土壤化学性质对土壤有效硅含量的影响。结果表明,宁波市耕层土壤有效硅(SiO2)平均含量为68 mg.kg-1,土壤有效硅含量丰富(≥130 mg.kg-1)、中等(100～130 mg.kg-1)、缺乏(50～100 mg.kg-1)和极缺水平(<50 mg.kg-1)的土壤分别占15.8%,5.5%,19.8%和58.9%。旱地有效硅的平均含量(95 mg.kg-1)高于水田(61 mg.kg-1),两者的缺硅土壤面积分别占各自总面积的58.8%和83.5%。不同土类的有效硅含量按以下次序递减:滨海盐土(133 mg.kg-1)>潮土(110 mg.kg-1)>水稻土(61 mg.kg-1)。在水稻土中,有效硅含量以渗育水稻土最高(88 mg.kg-1),淹育水稻土最低(49 mg.kg-1)。各地貌类型的土壤有效硅含量:滨海平原>水网平原>河谷平原>丘陵山区。土壤有效硅含量与pH、有机质的相关性均达极显著水平(P<0.01);而与有效磷、速效钾均无显著相关性。针对宁波市耕地严重的缺硅现状,提出了补施硅肥的建议。

Study on available silicon contents in cultivated land and its influencing factors in Ningbo city

An investigation study was conducted to analyze available silicon contents(SiO2)of 747 soil samples in nine counties(cities,districts) of Ningbo city,Zhejiang province and to determine the effects of land utilization,soil types,topography and soil chemical properties on available silicon contents in the soils.The results indicated that available silicon content in the cultivated soils averaged 68 mg·kg-1 and the soil samples with rich(≥130 mg·kg-1),medium(100-130 mg·kg-1),deficient(50-100 mg·kg-1),and very deficient levels(<50 mg·kg-1) accounted for 15.8%,5.5%,19.8% and 58.9% of total soil samples,respectively.The average silicon contents in upland soils(95 mg ·kg-1) were higher than that in paddy soils(61 mg·kg-1) and the soils with deficient silicon accounted for 58.8% and 83.5% of their total soil samples,respectively.Available silicon contents in different soil types decreased in the order: coastal saline soil(133 mg·kg-1)> fluvio-aquic soil(110 mg·kg-1)> paddy soil(61 mg·kg-1).Among paddy soils tested,the highest available silicon content(88 mg·kg-1) was obtained from percogenic paddy soil,and the lowest available silicon content(49 mg·kg-1) was obtained from submergic paddy soil.Available silicon contents in different landscape types decreased in the order: coastal plain> water-net plain> valley plain> hills and mountains.Available silicon contents in the soils were significantly correlated with pH and organic matter contents in the soils(P<0.01),and were not significantly correlated with available phosphorus and potassium contents in the soils.Aiming at the present situation of serious deficient silicon in Ningbo city,the corresponding recommendations of application of silicon fertilizer were put forward.