Restoration of a Hillslope Grassland With an Ecological Grass Species (Elymus Tangutorum) Favors Rainfall Interception and Water Infiltration and Reduces Soil Loss on the Qinghai-Tibetan Plateau

Abstract

[Abstract] Ecological grasses (eco-grass) have poor palatability and are less popular than forage grasses, receiving little attention for many years, despite their increased survival regarding livestock on the Qinghai-Tibetan Plateau. Eco-grass restoration has the functions of increasing vegetation coverage, preventing soil and water loss, conserving water sources, and preventing pika and insect pests. However, the effects of the eco-grass on soil and water conservation are still unclear. Here, a field experiment was conducted to determine the effects of an ecograss species (Elymus tangutorum) on the processes of soil and water loss in alpine hillslopes grasslands on the eastern Qinghai-Tibetan Plateau. The results showed that the soil loss rate decreased with the increase of litter biomass in the presence of the selected eco-grass. The presence of eco-grass reduced the soil loss rate by 65% and this was mainly associated with the increase of the rainfall infiltration rate and litter interception rate. Our findings showed that eco-grass could take into account both soil and water conservation and ecological benefits in alpine hillslope grasslands. Therefore, eco-grass should be considered and extensive application to maintain the multifunctions and stability of artificial hillslopes grassland on the Qinghai-Tibetan Plateau.