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

采用盆栽试验研究海盐渍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组成部分；（３）土壤生物量态氮的消长与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，

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

Pot experiments were carried out to study the effect of combining application of organic manure (silkworm manure) and inorganic fertilizer (urea and ammonium bicarbonate) on the biomass-N and N-supplying characteristics of coastal slightly saline soil. The results obtained showed that(1)application of both organic and inorganic fertilizers could significantly increase the soil biomass-C and biomass-N and the combining application of silkworm manure and inorganic fertilizer might cause a more increase of biomass-N than single application of silkworm manure or inorganic fertilizer; (2) soil biomass-N was an important link in soil nitrogen transformation and a major part of available N in soil; (3) there was a significantly close relationship between the changes of soil biomass-N and soil N-supplying characteristics, thus a strong immobilization of N fertilizer by microorganisms was always followed by a net N mineralization, which was most favourable for the growth and development of barley plant; and (4) silkworm manure was helpful in raising fertilizer utilization efficiency, especially for ammonium bicarbonate which can volatilize violently in coastal saline soil because of its higher pH, and it would be an efficient way to raise N utilization efficiency by combining application of various organic manures and inorganic fertilizers.