Investigation of C-Organic Content, Nitrogen, Phosphorus, Potassium Nutrients, pH Soil and C/N Ratio of Tidal Rice Fields in Sidomulyo Village, Anggana District, Kutai Kertanegara Regency, East Kalimantan

Abstract

ABSTRACT The purpose of this study was to investigate the content of organic C, Nitrogen, Phosphorus, Potassium nutrients, pH soil and C/N ratio in tidal paddy fields in Sidomulyo Village, Anggana District, Kutai Kertanegara Regency, East Kalimantan; use for productivity sustainability conservation; and identify the current fertility condition of the land and for sustainable management actions. The research was carried out by taking 50 soil samples from 10 determined tidal fields, each 5 samples per field, made into 1 kg of soil in a composite manner, so that 10 soil samples were obtained. Soil samples were taken using a soil drill with a depth of ±30 cm. The composite sample was analyzed at the Laboratory of Soil Science, Faculty of Agriculture, Mulawarman University. The results of laboratory analysis provide information that: pH soil parameter, all samples showed very acidic with an average acidity number of 4.28 (lowest 2.13, highest 3.88), two categories of C-organic content parameters identified, namely the moderate category of 4 samples, (ie: 2.13 %, 2.71%, 2.91%, and 2.93%); and high category, totaling 6 samples (ie: 3.23%, 3.27%, 3.30%, 3.36%, 3.45%, and 3.88%); Total Nitrogen content parameters were also identified in the medium category, totalling 7 samples (0.27%, 0.35%, 0.38%, 0.39%, 0.48%, 0.48% and 0.48%); high category, totaling 3 samples (0.31%, 0.34%, 0.58%); parameter of C/N ratio, all 10 samples showed low category; Parameter of Phosphorus available shows variation, in the low category there is 1 sample (ie 6.73 ppm), the medium category is 1 sample (10.18 ppm), the high category, there are 2 samples (ie 14.27 ppm and 14.82 ppm), very high category, as many as 6 samples (18.36 ppm, 23.27 ppm, 17.64 ppm, 32.36 ppm, 17.45 ppm, and 15.64 ppm), Parameter of Potassium available, all samples show a very high category. Keywords: Investigation, C-organic, C/N ratio, pH soil, Tidal rice field.