长期定位施肥对菜园土壤砷累积和分布的影响

Effect of Long-Term Located Fertilization on Arsenic Accumulation and Distribution in Garden Soil

为了解长期施肥对菜园土壤中砷累积和分布的影响,采集了沈阳农业大学蔬菜长期定位施肥试验基地5年的土壤样品(跨年份)进行分析。结果表明,1998-2009年,土壤砷含量只施有机肥的处理(A)比不施肥处理(B)高4.43%。2009年不同施肥处理不同土层土壤中砷的平均含量为0～20 cm 11.73 mg/kg、20～40 cm 8.28 mg/kg、40～60 cm 8.50 mg/kg;20～40 cm土层中As的平均含量比耕层中减少29.41%,40～60 cm土层中As的平均含量比耕层中减少27.54%;施用有机肥或化肥后土壤的砷含量多数有所提高,可见施肥是土壤中砷的主要来源;不施肥处理土壤中砷的含量呈逐年递增的趋势,说明土壤中的砷不仅仅是由施肥造成的,与小区的地理位置和环境也有很大的关系。

To understand the impact of long-term located fertilization on arsenic accumulation and distribution in the garden soil, the soil sample of 5-year （cross-year） from vegetable＇s long-term located fertilization experimental base in Shenyang A- gricultural University was analyzed. The results showed that only the As content in the soil of organic fertilizer processed（A） was 4.43 percentage points higher than that without fertilization （B） in 1998-2009. In 2009, the average As content in the soil of different soil layers in different fertilizer treatments was as following： 0-20 cm was 11.73 mg/kg, 20-40 cm was 8.28 mg/kg, 40~60 cm was 8.50 mg/kg; the As content in 20-40 cm soil layer was 29.41% less than that in plough layer; the As content in 40-60 cm soil layer was 27.54% less than that in plough layer. Moreover, the As content of the majority soil should be increased after organic manure or fertilize applied, it was thus clear that fertilization was one of the sources of arsenic in soil. However, the As content in control areas was also increasing year by year. Then it can be concluded the As content in the soil was not only caused by the fertilization, but also had a great relationship with the area location and its environment.