不同施肥处理对冬小麦干物质积累及土壤养分垂直分布的影响

采用田间试验法，在富磷缺钾的土壤上，研究了NP、NK、NPK处理与对照（CK）对冬小麦干物质积累和土壤养分垂直分布的影响。结果表明，随生育期的延长，小麦积累的干物质逐渐增加，直到成熟。同一生育期，小麦干物质积累表现为NPK〉NK〉NP〉CK。土壤中速效氮、磷、钾大多数分布在0～30cm土层，速效氮钾在50～70cm有富集，之后递减；速效磷在30cm以下骤减。随小麦的生长，同一处理土壤的速效氮、磷和钾呈“S”形变化，速效氮磷峰值在挑旗期，钾在返青期。同一生育期同一土壤深度，各施肥处理的速效氮、磷和钾均高于对照。由此，在生产上应该采取提高作物浅层根系活性和促进深层根系伸长的措施，充分利用土壤表层和深层富集的养分，这样既可增加作物产量，又可减少养分淋失造成的环境污染。

Effects of Different Fertilizer Treatments on the Dry Matter |Accumulation of Winter Wheat and Vertical Distribution of Soil Nutrient

In the rich P and deficient K soil,effects of different fertilizer treatments, such as CK,NP,NK and NPK,on the dry matter accumulation of winter wheat and vertical distribution of soil nutrient were studied under field conditions.The results showed that along with plant development,dry matter accumulation increased gradually until ripening stage.During the growth period,dry matter accumulated in wheat represented NPK>NK>NP>CK.Majority available N,P and K in soil distributed at the depth of 0~30cm.Partial available N and K can be collected in soil depth of 50~70 cm,then their concentration descending.Available P decreased sharply at depth of 30 cm.Along with wheat growth,available N,P and K in soil presented shape of "S",the peak value of the former two was at flagging stage,while that of the latter,at turning green stage.In the same growth period and at same soil depth,the three soil nutrients with different treatments were higher than those of CK.Therefore,measures of enhancing crop root activity at shallow soil depth and promoting crop root's development in deep soil depth should be adopted.Thus,rich nutrients at both shallow and deep soil depths can be fully utilized,which helped to increase crop yield and avoid environment contamination brought about by lost soil nutrients.