Uptake of a Hydrologic Tracer (Bromide) by Ryegrass from Well and Poorly‐Drained Soils

Abstract

Abstract Ryegrass ( Lolium perenne L.) accumulated an average 32% of applied bromide (Br − ) in aboveground biomass. Bromide uptake was greater on a well‐drained soil (38%) than a poorly drained soil (27%). Uptake was also affected by an interaction between season and N fertility. Bromide concentration of ryegrass was affected by interactions between soil drainage and season, and between soil drainage and N fertility. The magnitude of uptake shows Br − to be quite biologically reactive in the soil root zone. The impact of interactions between common experimental variables on Br − uptake makes it difficult to select settings where Br − uptake will be low. Consequently, the amount and pattern of uptake among common experimental variables greatly restricts the settings in which Br − is an appropriate hydrologic tracer.