Journal Article

Bare Patches Created by Plateau Pikas Contribute to Warming Permafrost on the Tibet Plateau

Zhao, Shuping, Nan, Zhuotong, Chen, Yuhong

2024

Overview

Plateau pikas, small mammals native to the Qinghai‐Tibet Plateau (QTP), create bare patches through burrowing. No previous assessment exists on their impact on permafrost. This study fills this gap by simulating hypothetical scenarios in the Three Rivers Headwaters Region of the QTP using the Noah‐MP model for the plant growing seasons during 2015–2018. Our findings reveal a significant increase in soil temperature in the active layer due to pika‐induced bare patches, particularly during July–August. The average temperature rise at 2.5 cm depth was 0.36°C in permafrost regions and 0.29°C in seasonally frozen ground regions during August. Minimal impact on unfrozen water content was observed, with a slight increase in deep soil layers in permafrost regions, and negligible in seasonally frozen areas. These findings underscore the previously unexplored influence of pika burrowing on permafrost temperature, suggesting a potential risk of accelerating permafrost degradation, especially in permafrost‐dominated regions. Plain Language Summary On the vast Qinghai‐Tibet Plateau (QTP), plateau pikas are actively excavating burrows, creating bare patches of exposed earth within the typical grassland landscape. These seemingly minor disturbances can have significant consequences, as they alter heat and water conditions within the underlying permafrost. However, a comprehensive understanding of how these pika‐made patches impact the permafrost remains elusive. To address this gap, our study employed a computer model and simulating scenarios with and without pika patches in the ecologically fragile Three Rivers Headwaters Region (TRHR) of the QTP. We found that the pika‐induced bare patches significantly raised permafrost temperatures, especially in the shallow soil layers. During August, the peak pika activity month, the average soil temperature at a depth of 2.5 cm increased by 0.36°C in permafrost zones and 0.29°C in seasonally frozen ground zones. While the patches had minimal impact on unfrozen water content in the active layer, the temperature rise in permafrost warrants future concern. Key Points Bare patches due to plateau pika burrowing warmed permafrost, particularly during peak activity months and in shallow soil layers Pika bare patches warmed permafrost and seasonally frozen ground by about 0.36°C–0.29°C, respectively, at a 2.5 cm depth in August Pika‐induced bare patches had negligible impact on the unfrozen water content in the active layer of permafrost

• Publisher: John Wiley & Sons, Inc,Wiley
• Subject: Active layer / bare patches / Frozen ground / Grasslands / Growing season / Headwaters / Moisture content / Permafrost / Permafrost temperatures / plateau pikas / Plateaus / Qinghai‐Tibet plateau (QTP) / Rivers / scenario analysis / Soil / Soil degradation / Soil layers / Soil temperature / Temperature / Temperature rise / warming permafrost / Water content