| dc.description.abstract | The level of soil fertility can be known through the approach of soil properties such as the activity of microorganisms in the soil. Good soil for plants, namely topsoil, is the top layer of soil with a solum of about 15 cm. Microorganism activity is the process of microorganisms carrying out living activities in the soil. This study aims to calculate and analyze soil chemical properties and soil microorganism activity in teak (Tectona grandis) and mahogany (Swietenia mahagoni) stands. This research was conducted at the Laboratory of Soil Biology, Faculty of Agriculture, University of North Sumatra. This study used two soil samples, namely soil under teak stands and soil under mahogany stands. The Variety Print Test was used to determine the effect of the type of stand with soil depth on the activity of microorganisms. The results of this study obtained the highest total number of microorganisms found in the soil at a depth of 20 cm, namely in teak stands of 113.37 x 107 CFU/ml with soil microorganism activity of 5.25 mg CO2/day. Meanwhile, in the Mahogany stand, it had 138.36 x 107 CFU/ml with microorganism activity of 4.6 mg CO2/day. Based on the results of tests conducted the soil depth was significantly different from the number of microorganisms at a depth of 60 cm. While the test results on the activity of microorganisms there is no significant difference to the significance. | en_US |
