摘要
为了解设施地土壤的理化性质,以江苏省苏北地区大棚土壤为例,研究种植年限分别为1,3,5,7 a大棚土壤含水量、全N、全P、全K和重金属含量的变化情况。结果表明,随着种植年限的增加,设施地土壤含水量显著降低,随着土层深度的增加,土壤含水量进一步降低。设施地土壤全N、全P和全K含量比大田高,特别是全N和全K积累量大,且分布于耕作层,随着土层深度的增加全N和全K含量变化较大;同时,随着种植年限增加,设施地土壤全N、全P和全K含量显著增加,7 a左右的设施地土壤20 cm耕作层中的全N含量分别为1.99,1.87,2.40 g/kg;全P含量分别为1.03,1.01,1.74 g/kg;全K含量分别为1.94,3.52,4.40 g/kg,且全N和全K含量随着土层深度的增加而逐渐降低,与土层深度的变化呈显著负相关关系。随着种植年限的增加重金属含量增加,7 a左右大棚种植年限扬州和连云港地区20 cm土层中的Pb含量分别为194,225 mg/kg;淮安地区不同种植年限20 cm土层的Cd含量分别为0.80,0.93,1.14,2.49 mg/kg;扬州和连云港地区无论种植年限多久,Cr含量均大于120 mg/kg;扬州地区As含量均大于25 mg/kg,Pb、Cr和As含量随着土层深度的增加而逐渐降低,与土层深度的变化呈显著负相关关系。所以设施地随着种植年限的增加,土壤理化性质会发生变化,应采取措施保持土壤含水量,防止土壤板结、盐渍化,消除重金属累积。
In order to know the physical and chemical properties of protected vegetable soil,water content,total N,P,K and heavy metal content in the protected vegetable soil were studied in the north of Jiangsu province with the different years of cultivation（1,3,5,7 years）.The results showed that water content significantly decreased with the increase of the cultivation time and soil depth.Total N,P and K contents in the protected vegetable soil were higher than the field soil,especially total N and total K contents.At the same time,total N,P and K contents increased in the protected vegetable soil with the increase of the cultivation time.In the 20 cm plough layer soil of cultivation for 7 years,total N was 1.99,1.87,2.40 g/kg,respectively.Total P was 1.03,1.01,1.74 g/kg,respectively.Total K was 1.94,3.52,4.40 g/kg,respectively.However,total N and K content gradually reduced with the increase of soil depth.The relationship,which total N and K content had an obvious negative correlation with the soil depth,was found.With the increase of the cultivation time,heavy metal content gradually increased.The Pb contents were 194,225 mg/kg in the 20 cm plough layer soil of cultivation for 7 years in Yangzhou and Lianyungang.At the 20 cm plough layer soil of cultivation for different cultivation years in Huaian,the Cd contents were 0.80,0.93,1.14,2.49 mg/kg.All the Cr content was higher than 120 mg/kg in protected vegetable soil with different cultivation years in Yangzhou and Lianyungang.Meanwhile,the results found that all the As content was higher than 25 mg/kg in protected vegetable soil of Yangzhou.Pb,Cr and As contents gradually decreased with the increase of soil depth.At the same time,it was found that Pb,Cr and As contents had a significant negative correlation with the soil depth.So after a few years of protected cultivation,physical and chemical properties of soil would change.Measures should be taken to maintain soil content,prevent soil harden and salinization,and eliminate heavy metal accumulation.
出处
《水土保持学报》
CSCD
北大核心
2011年第4期125-130,共6页
Journal of Soil and Water Conservation
基金
江苏省农业科技自主创新资金(cx(10)437)
关键词
设施土壤
土壤养分
土壤肥力
重金属
protected vegetable soil
soil nutrient
soil fertility
heavy metal
