Deterioration of soil fertility by land use changes in South Sumatra, Indonesia: from 1970 to 1990

Effect of land use on soil nutrients in the loess hilly area of the Loess Plateau, China

“…This is similar to other researchers (Lumbanraja et al, 1998;Rhoades et al, 2000;Priess et al, 2001;Liu et al, 2002;Pamela et al, 2005). Land use change, for example, from natural vegetation to agricultural land, or from grassland to arable land, can strongly impact soil carbon and nutrient concentrations.…”

Effect of land degradation on soil microbial biomass in a hilly area of south Sumatra, Indonesia

“…In the sampling area the wet season extends over 7 -9 months while the dry season over less than 2 months. Annual rainfall is approximately 1,500-2,000 mm and mean temperature is 22-25°C (Lumbanraja et al 1998). Primary forest was located in the upper part of the slope, between 800-1,200 m above sea level.…”

“…In the past two decades, the area covered by primary forest decreased by 44% whereas coffee-planted areas increased by 60% in hilly areas in Lampung province, south Sumatra, Indonesia (Syam et al 1997). A large number of studies have been carried out on the changes in soil chemical properties (Lumbanraja et al 1998), organic matter content . humus composition , soil enzyme activities (Salam et al 2001).…”

Cassava-Based Intercropping Systems on Sumatra Island in Indonesia: Productivity, Soil Erosion, and Rooting Zone

“…In Gunung Batin, the southern end of Sumatra Island, Indonesia, cassava is widely cultivated on gently sloping areas for the production of starchy materials. The soil in this region is classifi ed as a red acid soil (Acrisol), which is known to rapidly lose fertility after it is reclaimed for cultivation (Lumbanraja et al, 1998;Iijima et al, 1999;Iijima et al, 2003). The monoculture system and/or intercropping with cereal crops, such as maize and upland rice, which are commonly adopted in this region, may tend to accelerate soil degradation.…”