Problems have been widely encountered when trying to scale erosion results from plot to catchment level. Due to the complex hydrological response in catchment, the soil erosion from plot level does not always correlate with erosion measured at the catchment scale. An exper-iment was conducted to measure the soil erosion at both plot and catchment levels under coffee tree based crop in Lampung, Indonesia. Runoff and sediment were measured at the catchment of 10.2 ha, while seven erosion plots of 75 m2 were constructed inside the catchment. The erosion plots were designed as follows; (a) bare soil (control), (b) natural weeds (NW), (c) clean weeded coffee, (d) coffee with Paspalumcon jugatum (PC) in spot weeding, (e) cof-fee with PC in strip along the contour line, (f) coffee with NW in spot weeding, and (g) coffee with NW in strips. After one and a half years measurement, the rate of soil loss ranged from 0.12 t ha−1 (natural weed plot) to 0.87 t ha−1 (bare soil plot). On the other hand, the sediment yield from the catchment was 6.7 t ha−1 for 8-months measure-ment during the rainy season. These experiments indicate that, the sediment yield from the catchment level is more than ten times that of soil loss from plot scale. This is sup-posed, to be responsible for the gully erosion, collapse and
soil erosion from paddy field which occurred in the catch-ment. This result showed that the soil conservation strategy which is now mainly focused on only cropped areas must be revised, and the other sources of sediment yield must be taken care of to curtail downstream soil erosion.
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