Simultaneous measurement of runoff and leaching losses of bromide and phosphate using tilted beds and simulated rainfall

Abstract Small beds packed with soil were used to study intertill soil erosion and chemical transport processes. We compared the partitioning of bromide and phosphate between runoff and leaching, and related sediments rates (g/min) to bromide and phosphate concentrations in the runoff. Stainless steel tilted beds (1.0 x 0.5 x 0.1 m) with 2% slope were equipped with leaching and surface runoff collection funnels. A Tifton loamy sand was hand‐packed in the beds to a bulk density of 1.7 Mg/m3. Chemicals were sprayed uniformly to the soil surface and followed by a 2 h, 10 cm simulated rainfall. Runoff and leaching started after 27 min of rainfall and remained constant. Change in sediment rate, and bromide and phosphate concentrations from the first to the second runoff sample was related to splash transport. Breakthrough curves for leaching of bromide and phosphate were different and related to their affinity for the soil particle surfaces. This experimental technique may be useful for estimation of pesticide...