Drought Index Assessment Using Thermal Vegetation Index (TVI) Method and Soil Physic Approaches (A Case Study: Manyaran District, Central Java, Indonesia)

The early detection of areas that have the potential to experience drought is necessary to minimize the hazards of land drought. The study aimed to identify the current conditions of drought by TVI with actual soil physic characteristic approaches, and to find the determinant factors related to the dynamics of agricultural land drought conditions so as to determine land management strategies that are considered appropriate and efficient to prevent agricultural land drought. The method for analyzing the drought index was the Thermal Vegetation Index (TVI) method, which involved the calculation of the ratio between the Land Surface Temperature (LST) and the vegetation index using Normalized Difference Vegetation Index (NDVI). The method in this research was modified by adding soil physical indicators, including soil moisture content, bulk density, and pF value. The results showed that the land drought classes were normal drought (46.89% study area), mild drought (20.62% study area), moderate drought (14.10% study area), severe drought  (8.58% study area), and extreme drought (9.81% study area). Land drought was highly correlated to the soil's physical condition, negatively correlated with the moisture content (r -0.403) and bulk density (r -0.317), and positively correlated with the pF (r 0.429). Enhancing the soil’s capacity to absorb water and retain moisture through the addition of organic matter is one of the required techniques as a suitable recommendation to the issue after determining the determinant factors and present conditions.