膨胀珍珠岩对土壤有效磷分布的影响

Research on Effect of Expanded Perlite on Distribution of Available Phosphorus in Soil

采用盆栽试验,设膨胀珍珠岩与土壤按1%、2%、3%配比混合和分层(膨胀珍珠岩在下层)2个处理,研究了采自沈阳农业大学农工学院实验基地塑料大棚0～24cm土壤的养分的积累状况及剖面分布特性。结果表明:混合处理中,土壤速效磷在膨胀珍珠岩与土壤配比为1%和3%时聚集在土壤深层,配比为2%时聚集在土壤表层及作物根系层;盐分离子在配比为1%和3%时聚集在土壤表层,2%时聚集在土壤深层;膨胀珍珠岩的不同配比都能缓解土壤酸化现象,这种缓解作用随着膨胀珍珠岩配比的增加而加大;分层处理中,膨胀珍珠岩配比为1%、2%、3%时,土壤速效磷向作物根系层聚集,盐分离子向16～24cm土壤深层聚集;土壤pH:在配比为1%时,作物根系层>土壤表层;配比为2%、3%时均是土壤表层>作物根系层。

In order to offer theoretical basic for proper management of available phosphorous in soil, pot experiment was introduced to study the accumulation condition and the cross-section distribution of nutrients 0-24 cm in soil obtained from plastic tunnels in Shenyang agriculture university. The samples including mixture of soil with expanded perlite and layered samples（the expanded perlite at the lower level） at the degree of 1%,2%,3% respectively. The results showed that among the mixed samples ,the available phosphorus in sample 10,4 and 3% moved to deeper level in soil ,while in the 2% sample ,it accumulated in both the surface area and the root-layer. In sample 1% and 3%, the salt ions moved to the surface area ,and that of sample 2% moved to the deeper level in soil. All the samples of different mix-rate with expanded perlite finally alleviated the acidation of soil ,and the trend became stronger along with the increased proportion of expanded perlite in mixture. For the layered samples ,the available phosphorous all transferred to the root -layer for different mix-rate ,and the salt ions moved to deeper layer of 16-24cm in soil . Besides , in sample 1%, the pH in the root-layer was higher thanthat in the surface area,while in the rate o{ 2% and 3% ,it was in contrary.