Penentuan kategori konsentrasi berbagai peubah kimia kualitas, tanah pada kedalaman berbeda di tambak provinsi sulawei selatan, Indonesia [Determination of concentration categories of various soil quality chemical variables in different depths in brackishwater ponds of South Sulawesi Province, Indonesia]
Soil quality is one of the determining factors in the success and sustainability of brackishwater ponds, including brackishwater ponds in South Sulawesi Province, Indonesia. Nevertheless, up until now there have not yet been any data regarding the concentration categories of soil quality chemical variables for brackishwater ponds soil in Indonesia. This study was conducted with a purpose to determine the concentration categories of soil quality chemical variables as the first step in interpreting the soil quality of brackishwater ponds particularly in South Sulawesi and generally in Indonesia. Soil samples were taken at 1,196 sampling points, each of which was with two depths of soil. All of those sampling points were spread in 13 regencies in South Sulawesi. As many as 18 soil quality chemical variables were measured directly in the field or analyzed in the laboratory. t test was used to find out the difference of soil qualities in different depths. Concentrations of soil quality chemical variables were arranged from the smallest to the largest and then decile location and decile value were determined as a basis in determining the concentration category of each soil quality chemical variable. The results of study show that generally brackishwater ponds soil in South Sulawesi with the depth 0-0.2 m have lower acidity and toxic element (Fe, Al) and on the contrary the soil have higher macro nutrient element (N, P) compared to that in depth 0.2-0.5 m. Other soil quality variables such as SKCl, SP, and SPOS are relatively the same in both soil depths. The data of each soil quality variable have been arranged into concentration categories (very low, low, medium, high, very high) to facilitate comparisons with other data regarding soil quality for brackishwater ponds. The results of this study are not recommended to be used in determining the relationship between soil quality and brackishwater ponds productivity, but they can become a basis in determining the soil quality chemical variables of brackishwater ponds including the categories of very low, low, medium, high, or very high and make decisions to improve soil quality.