Full Title: Quantifying the ecological carrying capacity of alpine grasslands on the Qinghai-Tibet Plateau

Abstract

Ecological carrying capacity (ECC), as an efficient approach in sustainable management, also was used to indicate ecosystem stability in vulnerable ecoregions. In this study, we proposed a new framework of ECC quantification focusing on vulnerable ecoregions and analyzed ECC on the Qinghai-Tibet Plateau (QTP) based on the ecogeographical regionalization. Some indicators were introduced in ECC assessing, such as effective vegetation cover required to make soil water erosion lower than the threshold of soil loss (EVCwater), effective vegetation cover required to make soil wind erosion lower than the threshold of soil loss (EVCwind), and above-ground net primary production that can be used for human activities (UANPP). The results showed that: (1) EVCwater increased from northwest to southeast on the QTP, and exceeded 70% in the southeastern QTP; (2) EVCwind for the entire Qinghai-Tibet Plateau increased from southeast to northwest, and was ≤ 30% in most areas of the eastern QTP; (3) the UANPP in most study areas ranged from 0 to 408.69 g m−2 yr−1, with a regional average of 95.06 g m−2 yr−1, and areas with a UANPP < 0 g m−2 yr−1 were mainly distributed in the HID1 ecoregion; and (4) the average ECC for alpine grasslands on the Qinghai-Tibet Plateau is 1.47 sheep unit hm−2, although values increased gradually from northwest to southeast.