No abstract

Watatu Village is one of the villages located in Donggala Regency and as the capital city of South Banawa Sub-District which has significant potential in the agricultural sector, including cocoa plantations, oil palm trees, and paddy fields. This research aims as a source of information correlated to land-use policies and the erosion hazard index in Watatu Village, South Banawa Sub-District, Donggala Regency. The research was carried out by using the descriptive explorative method, and the observed variables were carried out through a survey. Soil sampling was determined purposively (purposive sampling) based on the category of land use and slope at the research location. Intact and incomplete soil samples were taken as many as 21 samples at seven land-use units. Sample analysis was performed at the Soil Science Laboratory on the Erosion Hazard Index, namely (1) soil texture, (2) soil structure, (3) organic matter content, and (4) permeability, and (5) bulk density. The results of the Erosion Hazard Index analysis showed that the high erosion hazard index was found in Land use unit 2 (mixed gardens), Land use unit 4 (cocoa gardens), Land use unit 5 (mixed gardens), and Land use unit 7 (Shrub). Thereby, conservation actions needed to preserve the environment to prevent or inhibit the rate of erosion and maintain the stability of land use.

This study aimed to examine land physical change against the erodibility of soil erosion. This study is a form of land use survey. It was performed in the Taweli watershed in the city of Palu. Sample was randomly taken. Research variables were rainfall erosivity, physical characteristics and value of soil erodibility, Length and Slope (LS), vegetation factor and soil management. The value of erosion was calculated based on USLE (Universal Soil Loss Equation) method. Study result revealed that the forest had the value of soil erosion of 0.18-2.15 ton ha-1 year-1 that categorized as very low erosion hazard level. Mixed farming land had the value of soil erosion of 6.97-29.29 ton ha-1 year-1 that categorized as low, shrubs was categorized into average to heavy erosion hazardous level of 89.44-1687.64 ton ha-1 year-1 and the primary forests had value of erosion of 1.68, 9.80 and 19.85 ton ha-1 year-1 , respectively which categorized as very low. Therefore, it can be inferred that land of shrubs have high value of erosion compared to the land use for forest and mixed farming agriculture.