土壤速效养分的吸附特征与生物有效性

应用化学分析、吸附反应和生物诊断方法,系统研究了六个土壤中养分的丰缺状况,确定了供试土壤存在的养分限制因子及其严重程度。结果表明,供试土壤普遍缺氮,部分土壤中磷、钾、硫、铁和铜供应不足,个别土壤中锌和硼含量偏低。在低锰浓度的吸附液中.土壤对锰的吸附强烈;铜、锌和硼吸附率不受相应吸附液浓度的制约;在高磷、硫浓度的吸附液中,各土壤对磷、硫的吸附率差距增大。三大土类的基础生产力不同,植株干重在2.73～5.55克/盆范围内变化,补充营养元素后,生产力显著提高,土类间差距缩小。 运用系统研究法得出的这些结论,针对性强,但个别环节尚需继续改进。

THE ADSORPTION CHARACTERISTIC AND BIOLOGICAL AVAILABILITY OF SOIL NUTRIENTS

Chemical analysis, adsorptive reaction and biological diagnosis were systematically employed to study the status of nutrients in six soils and determine the demanding order for fertilizers. The results showed that N deficiency was widely existed in the soils, followed by P, K, S, Fe,Cu deficiency, and Zn and B in some soils. The deficient degree and order of soil nutrients varied among the test soils. A strong adsorption for Mn was found in the low Mn concentration solution. Cu, Zn and B adsorption rates were not influenced by their concentrations in corresponding adsorption solutions. Phosphorus adsorption differed among the six soils. The basic soil productivity (plant dry weight) varied from 2.73 to 5.55 g/ pot and was significantly increased by fertilization with small differences among three soil types.