The soils physicochemical properties of monoculture land in several slopes at Northern Areas of Mount Talang

Abstract In the northern area of Mount Talang with some steep slopes (more than 30°), the local community implements an intensive monoculture agricultural system that can accelerate land degradation in the long term. Study was aimed to examine the soils physicochemical properties of monoculture land on several slopes in the northern foothill of Mount Talang. Survey method and soil sampling were implemented in this research, using a purposive random sampling toward the monoculture land on slopes> 45%, 25-45%, 15-25%, 8-15%, and the forest as control, at 0-20 cm and 20-40 cm depth. The results revealed that the soil texture that dominates the forest and monoculture cropping system is sandy loam. In addition, soil water content increases by the increased soil layer depth as well, with highest level observed in monoculture cropping system 25-45% (73.72%). Soil bulk density ranging from 0.4-0.6 g / cm3, or have the same tendency at both soil depths. The total pore space of forest land and monoculture agricultural land is 75%, categorized as high. The highest soil organic C content was found in monoculture agricultural land with a slope of >45%. The value of pH for all land uses was 5.15-5.29 on acid criteria. The cation exchange capacity was above 40 me / 100g and the total N content is 0.8-1.6%, so both of them are categorized as very high. Based on the data, the soils physicochemical properties of monoculture cropping system on several slope classes similar to the forest. The land quality for monoculture cropping system is still maintained, even though it is on the upper slopes of the foothill of Mount Talang. However, in the monoculture cropping systems will trigger the loss of soil organic matter, so the addition of soil organic matter content should be prioritized, especially in the agricultural land management of this area.