有机无机肥料配合施用对滨海盐土土壤生物量态氮及土壤供氮特征的影响

EFFECTS OF COMBINING APPLICATION OF ORGANIC AND INORGANIC NITROGEN FERTILIZERS ON BIOMASS NITROGEN AND NITROGEN- SUPPLYING CHARACTERISTICS OF COASTAL SALINE SOIL

采用盆栽试验研究滨海盐演化土上蚕粪与无机氮肥（碳铵和尿素）的施用对土壤生物量态氮和土壤供氮特征的影响，指出（１）施肥均能明显地提高土壤生物量态碳和生物量态氮的含量，蚕粪与无机氮肥配合施用比化肥单施或蚕粪单施更能增加土壤生物量态氮含量；（２）土壤生物量态氮是土壤氮素转化的重要环节，也是土壤有效氮的重要组成部分；（３）土壤生物量态氮的消长与土壤的供氮特征关系极为密切，只要前期有强烈的微生物固持无机氮肥过程，则中、后期势必会发生无机氮的释放过程，这一点对麦类作物生长发育极为重要；（４）蚕粪能有效地提高无机氮肥的利用率，尤其是碳铵，由于在滨海盐渍化土壤上氨的挥发很严重，因此，寻求与无机氮肥相配施的合适的有机肥料种类是提高滨海盐渍化土上氮肥利用率的最有效途径。

ot experiments were carried out to study the effect of combining applicationof organic manure(silkworm manure)and inorganic fertilizer(urea and ammoniumbicarbonate)on the biomass-N and N-supplying characteristics of coastal slightlysaline soil.The results obtained showed that(1)application of both organic andinorganic fertilizers could significantly increase the soil biomass-C and biomass-Nand the combining application of silkworm manure and inorganic fertilizer mightcause a more increase of biomass-N than single application of silkworm manure orinorganic fertilizer;(2)soil biomass-N was an important link in soil nitrogen tran-sformation and a major part of available N in soil,(3 )there was a significantlyclose relationship between the changes of soil biomass-Nand soil N-supplying cha-racteristics,thus a strong immobilization of N fertilizer by microorganisms wasalways followed by a net N mineralization, which was most favourable for the gro-wth and development of barley plant,and(4)silkworm manure was helpful in rai-sing fertilizer utilization efficiency,especially for ammonium bicarbonate which canvolatilize violently in coastal saline soil because of its higher pH,and it would bean efficient way to raise N utilization efficiency by combining application of variousorganic manures and inorganic fertilizers.