EFFECTS OF EM (EFFECTIVE MICROORGANISM) ORGANIC FERTILIZER APPLICATION ON THE SOIL ENVIRONMENT UNDER GREENHOUSE CONDITION.

EM (effective microorganism) technique has been widely used in environmental protection field, while its application in the improvement of agricultural soil was seldom studied. In this study, EM was used to ferment the EM organic fertilizers, and these fertilizers were applied to the tomato cultivated soils under the greenhouse condition. Isolation layers were buried into the soils with different depths of 20 cm (D1), 30 cm (D2) and 40 cm (D3). The application amounts of organic fertilizer were 2800 kg/ha (F1), 3600 kg/ha (F2) and 4400 kg/ha (F3), respectively. The soil salt content, the available nutrient concentrations, as well as the physical indicators of the greenhouse soil were observed. Results showed that compared to CK, the treatments reduced the salinity of soil in plough layer by 7.7-39.2%. The salt removing effect is the most satisfactory when the EM organic fertilization amount was 3600 kg/ha. The treatments increased the soil organic matter content by 4.7-22.9% and field capacity by 3.4-18.8%, in comparison to CK. However, the soil available N, P and K concentrations were decreased by 4.4-18.4%, 5.4-23.7% and 5.3-16.2%, respectively, under different treatments. The buried depth of straw layer had no obvious effects on soil physical indicators and available nutrient concentrations. Our results suggested that the EM organic fertilizer application could create a better growth environment for crops when compared to inorganic fertilization. From the perspective of soil improvement, 3600 kg/ha of organic fertilizer application amount combined with 30 cm buried depth of straw layer was recommended. [ABSTRACT FROM AUTHOR]