Multi-decadal variation and driving factors of the alpine meadow landscape fragmentation on the Qinghai-Tibet Plateau: A case study of Henan County

• Bare meadow patches far exceed healthy meadows in number, but are smaller in area. • Bare meadow patches decreased by 12.95 % during 1972–2019. • Wind speed accounts for 0.69 of variation in bare meadow patch area. • Abiotic drivers’ explanation rate (75.74 %) is three-time of biotic drivers (24.82 %) • Rodent damage has a higher explanation rate (0.78) than livestock size (0.20) The alpine meadow landscape on the Qinghai-Tibet Plateau (QTP) is facing the threat of fragmentation. At present, there is a lack of understanding about its long-term evolution and the roles of multi-factors in this process. With the assistance of satellite images spanning over five decades, this study comprehensively assessed the trend of meadow fragmentation and quantified the importance of abiotic (climate and topography) and biotic factors (livestock and small mammal) at the county scale. Their explanatory rates were quantified using innovative analytical methods, filling our knowledge gap in understanding the synergistic effects of multiple factors on long-term meadow evolution. The results show that: (1) The area of bare meadow patches decreased by 12.95 % (65.24 km 2 to 56.79 km 2 ) during 1972–2019, and the average landscape fragmentation index was 3.36 in 2019, and rose from 1972 to 2007 and then stabilized; (2) Abiotic drivers played a dominant role in meadow fragmentation, achieving an explanation rate of 75.74 %, three times higher than biotic factors. In particular, annual average wind speed was the most important (R 2 = 0.69, P < 0.01) to the change in the area of bare meadow patches; Altitude had a mixed effect (intensified fragmentation at 3201–3300 m and 4101–4300 m, and alleviated it at 3401–3500 m and 3901–4000 m, due mainly to differential accessibility and hence disturbance). Shady slopes, steep slopes and bottomland were all hotspots of bare patches; and (3) The most important biotic factor was identified as the area of small mammal-damaged meadow, achieving an explanation rate of 24.82 %, and its correlation with bare patch area was as high as 0.78 ( P < 0.01). In contrast, livestock quantity had a negligible effect on meadow fragmentation (R 2 = 0.02, P > 0.05). Thus, abiotic factors are the primary driving force behind the fragmentation of alpine meadows. These empirical results gathered from long-term satellite data provide convincing evidence as how the QTP alpine meadows should be precisely managed to prevent fragmentation (such as pika management and zonal protection of fragile terrain).