Main content area

Impact of natural gullies on groundwater hydrology in the Zoige peatland, China

Li, Zhiwei, Gao, Peng
Journal of hydrology 2019 v.21 pp. 25-39
basins, cold, cutting, groundwater, highlands, peat, peatlands, ravines, saturated hydraulic conductivity, seepage, water table, China, Yellow River
The study area was in the upland peatland within the Zoige basin with elevations ranging between 3400 and 3800 m. It is located in the source area of Upper Yellow River that is developed on the Qinghai-Tibet Plateau, China.We examined possible influence of two different types of gullies on groundwater hydrology in this alpine peatland, the gullies whose beds cutting through the peat layer and those whose beds are within the peat layer. We measured saturated hydraulic conductivity, hydraulic head, and water table levels both vertically and horizontally in three representative sites distributed in the study area representing blanket peatland and peats surrounded by two types of the gullies during May 11–23, 2017. Using these data, we showed that different patterns of these parameters in both directions may be clearly observed among the three sites.We have shown for the first time in this region that (1) gullies with the bed cutting through the peat layer may have profound impact on peat groundwater hydrology; (2) groundwater seepage at the bottom of the peat layer may be enhanced by gullies with the bed cutting through the peat layer; and (3) increased groundwater seepage could be an additional cause for peatland degradation during the prolonged dry and cold period of a year.