Initial soil properties of the restored degraded area under different vegetation cover in UB Forest, East Java, Indonesia

Abstract

Forest ecosystem degradation due to conversion into agricultural land is increasingly widespread in tropics. This study aimed to determine the initial properties of forest soils in some restoration areas under different vegetation cover. The restoration sites were divided into three areas, namely intensive agricultural land (PI), abandoned coffee plantation (KTT), and remnant protected forest (HLS). In each restoration area, soil samples were taken at top 20 cm depth of soil from five sampling points with three replications. As a comparison, soils were also sampled from the reference sites (RS). Soil samples were then analyzed for some soil properties in the laboratory such as soil physical properties (soil aggregate, bulk density, soil moisture), soil chemical properties (organic matter, pH, electrical conductivity), and soil biological properties (soil bacteria). Results showed that soil physical and chemical properties measured in restoration areas were significantly different from RS (p<0.05). Soil physics properties among three restoration areas were not statistically different (p>0.05), but the soil chemical properties were statistically different. This soil chemical difference was presumably caused by spatial variation and vegetation cover. The diversity of soil bacteria in all studied areas was not statistically different (p<0.05) even though the environmental conditions in each area were different. Among soil properties showed interactions that affected each other based on multivariate data analysis. Forest conversion into agricultural land use had a negative impact on soil properties and tends to decrease soil quality and health.