Soil erosion under different plant cover types and its influencing factors in Napahai Catchment, Shangri-La County, Yunnan Province, China

Abstract

Data on soil erosion is scarce for the Napahai Catchment in the Qinghai-Tibet Plateau. Specifically, greater information on soil erosion under effects of different plant cover types within this region is required for soil and water conservation as well as to initiate sustainable land use resource practices in Shangri-La County, Yunnan Province, China. This study investigated five representative plant cover types in Napahai Catchment to observe surface runoff and sediment yield. These included barren land, 1-year revegetated plot, three-year revegetated plot, grassland, and pine forestland. They were subsequently analyzed to determine their effects on soil erosion. Results showed that surface runoff and sediment yield were reduced with an increase in plant cover. However, different plant cover types produced significantly different results in surface runoff and sediment yield. Surface runoff volume followed the order barren land > 3-year revegetated plot > pine forestland > 1-year revegetated plot > grassland, whereas sediment yield volume followed the order barren land > 1-year revegetated plot > 3-year revegetated plot > pine forestland > grassland. In addition, soil organic matter and plant cover were closely correlated to surface runoff and soil loss in the Napahai Catchment. Grassland revegetation, in particular, would be a good initial step to take to prevent and control surface runoff and sediment yield during ecological restoration of the Napahai Catchment. This is owing to its natural advantages in soil and water conservation. Field observations could also be helpful to collect much needed information on the region that can subsequently act to prevent and protect against soil erosion, preventing the Napahai Wetland from deteriorating further while simultaneously improving land resources.

Keywords:

• revegetation
• runoff
• sediment yield
• Napahai
• Shangri-La
• Qinghai-Tibet plateau

Acknowledgements

We thank Brian Doonan (McGill University, Canada) for providing language help in writing this article and providing useful suggestions. This work was supported by the Chinese National Science and Technology Support Program (grant numbers 2011BAC09B04-03 and 2014BAD15B03) and the National Nature Science Foundation of China (grant number 41261079).