Experimental study on improving the utilization rate of underpasses of bundled linear infrastructure on Tibetan Plateau

Abstract

Wildlife crossing structures (WCSs) are an important measure to protect biodiversity and reduce human-wildlife conflict, especially for bundled linear infrastructure. The aim of this study was to evaluate two “management and behavioral” factors (salt blocks and feces) in relation to two “structural factors” (underpasses’ dimension and distance of bundled linear infrastructure) along Qinghai-Tibet bundled linear infrastructure (Qinghai-Tibet railway alignment runs parallel to the Qinghai-Tibet highway) and Gonghe-Yushu bundled linear infrastructure (Gonghe-Yushu expressway is parallel to the Gonghe-Yushu highway) using infrared cameras. Eight underpasses were monitored in the Qinghai-Tibet railway and six in the Gonghe-Yushu expressway, with half of the induced experimental group and half of the control group in each area. The monitoring shows that the Qinghai-Tibet railway area has richer species diversity than the Gonghe-Yushu expressway area. Salt block and feces induction experiments showed that the relative abundance index (RAI) of the experimental and control groups did not reveal significant differences in both areas. In addition, we found that the wider the width of the underpasses, the higher the utilization rate of kiang (Equus kiang) and wolly hare (Lepus oiostolus). And the distance from the adjacent linear infrastructure was positively correlated with the frequency of wolly hare, while no correlation was found with other species. In summary, this study found that salt block and feces induction could not improve the utilization rate of ungulates to underpasses of bundled linear infrastructure on Tibetan Plateau, and preliminary understood the factors affecting the utilization rate of underpasses.