Fig. 8
From: Rural earthen roads impact assessment in Phewa watershed, Western region, Nepal
Increase of (a) black top roads network length and, (b) earthen roads network length in Phewa watershed over the past 3 decades. The horizontal scale starts in the year 1979 (0 corresponds to the year 1979). Note that for the black top roads increase case (plot (a)), the growth is defined by a 2nd order polynomial trend. Only 17 km of black top roads built more than 30 years illustrates well the few considerations in developing a paved road network in Nepal. For the earthen roads increase case (plot (b)), the growth is well defined by an exponential trend and clearly illustrates the earthen roads construction “boom” occurring in Nepal over the past decade