The traditional transhumance grazing system on the Qinghai-Tibetan Plateau (QTP) is being replaced by a system in which pastoralists are allocated fixed areas for grazing. In this context, we conducted experiments to evaluate a possible change to seasonal grazing of young animals for weight gain, and the effects of grazing management (continuous grazing (CG) vs rotational grazing (RG)) and stocking rate (SR) on the performance and behaviour of Oura-type Tibetan sheep. In Experiment 1 (June–December 2014), 72 Tibetan sheep (initial bodyweight (BW) 32.2 ± 3.37 kg) were allocated to one of three treatments: (1) CG24 – eight sheep grazed continuously in a single 2-ha plot for the entire duration of the experiment; (2) RG24 – eight sheep grazed in a 1-ha plot from June to September (growing season), and then moved to a new plot for September–December grazing (early cold season); (3) RG48 – eight sheep grazed in a 0.5-ha plot, but otherwise as for RG24. All treatments had three replicates. In Experiment 2 (September–December 2014), 48 Tibetan sheep (initial BW 46.3 ± 1.62 kg) were used to repeat the RG24 and RG48 treatments imposed in the early cold season of the Experiment 1. In both experiments, increasing SR significantly reduced bodyweight gain (BWG) per head and increased BWG per ha in the RG treatments. In Experiment 1, RG, compared with CG, did not significantly affect BWG per head, BWG per ha, or feed utilisation efficiency. In both experiments weight gain was small or negative in the early cold season. These results indicate that removal of sheep at the onset of the cold season will be important for retention of the weight gain achieved in the growing season but choice between a CG and RG grazing system is unimportant for the production efficiency in the proposed grazing system of Tibetan sheep.

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Large‐scale patterns of biodiversity and formation have garnered increasing attention in biogeography and macroecology. The Qinghai‐Tibet Plateau (QTP) is an ideal area for exploring these issues. However, the QTP consists of multiple geographic subunits, which are understudied. The Kunlun Mountains is a geographical subunit situated in the northern edge of the QTP, in northwest China. The diversity pattern, community phylogenetic structures, and biogeographical roles of the current flora of the Kunlun Mountains were analyzed by collecting and integrating plant distribution, regional geological evolution, and phylogeography. A total of 1911 species, 397 genera, and 75 families present on the Kunlun Mountains, of which 29.8% of the seed plants were endemic to China. The mean divergence time (MDT) of the Kunlun Mountains flora was in the early Miocene (19.40 Ma). Analysis of plant diversity and MDT indicated that the eastern regions of the Kunlun Mountains were the center of species richness, endemic taxa, and ancient taxa. Geographical origins analysis showed that the Kunlun Mountains flora was diverse and that numerous clades were from East Asia and Tethyan. Analysis of geographical origins and geological history together highlighted that the extant biodiversity on the Kunlun Mountains appeared through species recolonization after climatic fluctuations and glaciations during the Quaternary. The nearest taxon index speculated that habitat filtering was the most important driving force for biodiversity patterns. These results suggest that the biogeographical roles of the Kunlun Mountains are corridor and sink, and the corresponding key processes are species extinction and immigration. The Kunlun Mountains also form a barrier, representing a boundary among multiple floras, and convert the Qinghai‐Tibet Plateau into a relatively closed geographical unit.

Large-scale patterns of biodiversity and the underlying mechanisms that regulate these patterns are central topics in biogeography and macroecology. The Qinghai-Tibetan Plateau (QTP) is a natural laboratory for studying these issues. However, most previous studies have focused on the entire QTP, and the independent physical geographical subunits in the region are not well understood. We studied the current plant diversity on the Kunlun Mountains, an independent physical geographical subunit located in northwest China, on the northern edge of the QTP. We integrated measures of species distribution, geological history, and phylogeography, and analyzed the taxonomic richness, origin time, and community phylogenetic structure of the plants present in the area. The distribution patterns of 1,911 seed plants highlighted that species were located mainly in the eastern regions of the Kunlun Mountains. Chinese endemic species of seed plants accounted for 29.8% of the total species on the Kunlun Mountains. The biodiversity patterns and mean divergence times (MDT) indicated that the eastern region of the Kunlun Mountains was the center for biodiversity conservation, particularly in the southeastern region, which has served as a museum for plant diversity on the Kunlun Mountains. According to the MDT, the origin time of the Kunlun Mountains’ flora (KMF) was early Miocene (19.40 Ma), and the KMF is ancient. The biogeographical roles of the Kunlun Mountains were corridor and sink, and the corresponding key processes were species immigration and extinction. The extant biodiversity on the Kunlun Mountains has occurred through species recolonization after climatic fluctuations and glaciations during the Quaternary. The Kunlun Mountains also formed a barrier, representing a boundary among multiple floras, and converted the QTP into a closed physical geographical unit. The nearest taxon index indicated that habitat filtering may have played an important role in biodiversity patterns.

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