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Soil erosion is a severe risk on the sloping agricultural land due to improper managements. This study aimed to evaluate and compare the dynamics of soil loss and runoff under different land use types in order to fi nd the best soil erosion control for sustainable land use planning. A field trial was conducted in Bor Krai village, Mea Hong Son Province, North-Western Thai Highlands during 2008-2009. Four land use types were selected for comparative measurement, including i) 4-year-fallow land (FaL), ii) mixed orchard (MixO), iii) maize (M) and iv) upland rice (UR). Surface runoff (SR) and soil loss (SL) were monitored after each effective rainstorm using modifi ed Gerlach troughs (GT). The GT was made of a bamboo and linked to a 50-litre container by a rubber hose. The size of GTs was 0.5-0.7 m long and 0. 0.2 m diameter. The GTs were installed perpendicular to the contour line at the lower part of each land use. The results showed that, during the 2-yr, monoculture with inappropriate soil water conservation caused the fi rst average highest values of SR and SL (SR=299 m³ ha-1) and (SL=3.4 t ha-1) while FaL yielded the lowest SR (41 m³ ha-1) and SL (0.01 t ha-1) amounts. Moreover, further study is required for long-term prediction to estimate annual soil loss under different land use types. [ABSTRACT FROM AUTHOR]

Steep slopes, erodible soils, rill and ephemeral gullies, compaction due to wheel traffic and human trampling are common features in vineyards around the world and result in high soil erosion rates. However, little is known about seasonal and spatial variations of soil erosion rates due to factors such as the impact of the vine plantation, harvest, and tillage on the soil redistribution over the long-term temporal scale. The goal of this study is to assess long-term soil erosion rates and the impact of management on sediment and runoff yield by means of Gerlach troughs and a topographical approach based on botanic benchmarks in two paired vineyards with different ages (3 and 35 years) located on the hillslope of the Ruwer-Mosel Valley (Germany). We studied: i) soil profiles and properties at different hillslope locations and ii) soil redistribution and erosion by means of topsoil level maps applying botanic benchmarks using the Stock Unearthing Method (SUM), RUSLE (Revised Unviersal Soil Loss Equation) and Gerlach troughs. The SUM showed that the old vineyard’s erosion rates ranged from 3.3 to 3.8 Mg ha −1 yr −1 , which was similar to the Gerlach trough measurements, and we demonstrated that the soil erosion rates depended on rainfall characteristics and human disturbances due to tillage, harvest trampling, and compaction by heavy machinery. Data from the SUM in the young vineyard showed 62.5 Mg ha −1 yr −1 of soil loss, which is a consequence of severe soil disturbance during the planting of the new vineyard. Finally, to prove the reliability data, RUSLE showed higher soil loss in the young vineyards (19.46 Mg ha −1 yr −1 ) than in the old ones (11.28 Mg ha −1 yr −1 ). [ABSTRACT FROM AUTHOR]