The simple two-ray model and FRIIS free-space model have been widely used in the literatures as the propagation models for the performance analysis of Mobile Ad hoc NETwork (MANET). These models are too simple to represent a real world network. In the real world scenarios, the environmental clutter varies widely for a given distance between two mobile nodes and has a strong impact on the performance of the routing protocols. This paper shows the impact of different shadowing, fading and inter-channel interference effects on the performance of three categories of routing protocols i.e. proactive, reactive and hybrid, in MANET environment.