SOIL PARAMETERS AT INTENSIVE RICE FIELD IN THE MEKONG DELTA

Abstract

The study aimed to evaluate the changes in total nitrogen, total phosphorus and organic matter content in the topsoil of intensive rice fields. The experimental field of 200m² is located in the corner of a large field to unify farming activities such as seeding density, fertilizer quantity, and pesticides application. Five topsoil samples at a depth of 10cm was collected at five points on the experiment field, mixed the samples and took about 1kg of samples for analysis and evaluation. Soil samples were collected in two consecutive farming seasons including the 3^rd crop and the next Winter – Spring crop. The results of the analysis showed that the changes in total phosphorus in both cultivation crops decreased in the first 2 weeks but there was a difference after that; soil in the 3^rd crop has the total phosphorus content increasing over time, but it tends to be stable in the Winter-Spring crop. However, total nitrogen content was opposite, in the first four weeks total nitrogen was stable in the 3^rd crop but tended to increase in the Winter-Spring crop; and in the later period are stable for both crops. The soil organic matter content tended to be stable from the beginning to the end of the growing season in both crops. The results show that there are fluctuations in the soil nutrient and soil organic matter content in the intensive rice cultivation rice field and need to be studied further.