Effects of different restoration measures on soil stoichiometric characteristics of plateau highway slopes

To effectively guide the protection and restoration of ecosystems in an ecologically fragile area of the Tibetan Plateau, we explored the short-term impacts of different restoration measures on soil stoichiometriccharacteristics of the plateau expressway slope. We carried out three types of slope restoration measures: 1) natural restoration, 2) replanting grass seed plus covering soil treatment, and 3) turf back-laying on the Jiuma highway in the Aba Tibetan and Qiang Autonomous Prefecture of Sichuan Province. We measured the soil organic carbon (SOC), total nitrogen (STN), total phosphorus (STP), and total potassium (STK) contents and soil stoichiometric characteristics of these slope restoration measures as well as controls. The results showed that the contents of SOC, STN, STP, SOC ꞉ STN, SOC ꞉ STP, SOC ꞉ STK, STN ꞉ STP, STN ꞉ STK, and STP ꞉ STK under the turf back-laying restoration measures were significantly higher than those under other restoration measures (P < 0.05). From the perspective of soil fertility, the soil quality index (SQI) was used to evaluate the restoration effects of the three measures, and the SQI value under the turf back-laying restoration measure was higher than that under the other two restoration measures. We believe that the turf back-laying restoration measure shows the best short-term results for the restoration of highway slopes in plateau areas.