Aggregate stability by the “high energy moisture characteristic” method in an oxisol under differentiated management
01/Oct/2014
Studies testing the High Energy Moisture Characteristic (HEMC) technique in tropical soils are still incipient. By this method, the effects of different management systems can be evaluated. This study investigated the aggregation state of an Oxisol under coffee with Brachiaria between crop rows and surface-applied gypsum rates using HEMC. Soil in an experimental area in the Upper São Francisco region, Minas Gerais, was studied at depths of 0.05 and 0.20 m in coffee rows. The treatments consisted of 0, 7, […]
Nutritional diagnosis of coffee plantations in the Upper Jequitinhonha Valley, Minas Gerais State, Brazil: dris norms and critical nutrient ranges
01/Aug/2009
In the Diagnosis and Recommendation Integrated System (DRIS), norms for coffee in the Upper Jequitinhonha Valley, Minas Gerais, Brazil, have not been established yet. The lack of these norms hinders the application of the DRIS to the coffee plantations in the region. The foliar diagnosis, based on the DRIS and on critical reference ranges, stands out among the tools that allow an efficient use of fertilizers. This study aimed to determine DRIS norms as well as to establish values of […]
Use of microwave radiation to evaluate soil microbial biomass
01/Dec/1999
The objective of this work was to determine carbon and nitrogen content in the soil microbial biomass by comparing microwave radiation and chloroform fumigation using the extraction and incubation methods. Two soil samples (Dark-Red Podzolic) were submitted to incubation and extraction after chloroform fumigation and microwave radiation during different periods (2, 5, 10, 15, 20, 30, 40 and 50 min). Two minutes under microwave radiation were sufficient to determine C and N content in the soil biomass using incubation and […]
