The increased proportion of pesticide-vulnerable taxa downstream of the forested reaches was mainly observed several months after contamination and was explained by enhanced recolonization processes (Liess and von der Ohe, 2005). Most previous studies did not specifically consider the influence of the UFR during the main CGH 2466 of pesticide application, except for Schäfer et al. (2007), who observed the influence of forested stream reaches less than 1 month after pesticide exposure. In a different study, Schäfer et al. (2012) showed that the thresholds for community-level pesticide effects were higher in streams with UFR. However, follicle-stimulating hormone (FSH) remained unknown whether the higher threshold is related to reduced mortality of vulnerable invertebrates after pesticide exposure or enhanced recolonization. Furthermore, Harding et al. (2006) showed that forested headwaters can change physico-chemical habitat characteristics downstream. However, none of the previous studies using the SPEAR approach investigated exactly which characteristics of the forest influence the vulnerable taxa downstream of the forested reach.