Wetland ecosystems in the Qinghai-Tibet Plateau (QTP), the region with the richest biodiversity and the most important ecological barrier function at high altitudes, are highly sensitive to global change, and wetland plants, which are important indicators of wetland ecosystem structure and function, are also threatened by wetland degradation. Therefore, a comprehensive study of changes in the geographical distribution pattern of plant diversity, as well as species loss and turnover of wetlands in the QTP in the context of global climate change is of great importance for the conservation and restoration of wetland ecosystems in the QTP. In this study, species turnover and loss of 395 endemic wetland plants of the QTP were predicted based on the SSP2-4.5 climate change scenarios. The results showed that there were interspecific differences in the effects of climate change on the potential distribution of species, and that most endemic wetland plants would experience range contraction. Under the climate change scenarios, the loss of suitable wetland plant habitat is expected to occur mainly in parts of the southern, north-central and north-western parts of the plateau, while the gain is mainly concentrated in parts of the western Sichuan Plateau, the Qilian Mountains, the Three Rivers Source Region and the northern Tibetan Plateau. Overlaying the analysis of priority protected areas with the established protected areas in the QTP has resulted in the following conservation gaps: the eastern Himalayan region, midstream of the Yarlung Zangbo River, the transition zone between the northern Tibetan Plateau and the Hengduan Mountains, Minshan-Qionglai mountain, Anyemaqen Mountains (southeast) to Bayankala (southeast) mountains, the southern foothills of the Qilian Mountains and the northern Tibetan Plateau region. In the future, the study of wetland plant diversity in the QTP and the optimisation of protected areas should focus on the conservation gaps. This study is of great importance for the study and conservation of wetland plant diversity in the QTP, and also provides a scientific basis for predicting the response of wetland plants to climate change in the QTP.

Industrial chili peppers contain more than 100 times the capsaicin content of common chili peppers; these peppers are primarily used for industrial processing and capsaicin extraction. Chili peppers thrive in warm temperatures, require plenty of sunlight, and are drought-resistant; therefore, making the high-altitude climate of Tibet ideal for their cultivation. Endophytes are microorganisms that can inhabit healthy plants at various stages of their life cycle. Through long-term co-evolution, endophytes and host plants establish a mutually beneficial symbiotic relationship, which assists plants in secondary metabolite production. This study investigated the differences in endophyte community structure across various lines of industrial chili peppers. It also explored the relationship between capsaicinoids and endophyte community composition in high-altitude habitats of Tibet using high-throughput sequencing to obtain fundamental data on industrial chili pepper endophytes. The results showed that the diversity of endophyte communities was characterized by conservatism among groups and that the composition and community structure of endophyte communities were specific to different groups. Community composition analysis revealed that there were generally consistent dominant phyla of endophytic microorganisms in industrial chili peppers, although differences in their relative abundance percentage were observed. Bacterial community composition at the genus level was less affected by capsaicin concentration across different groups; however, the fungal community composition at the genus level was more responsive to capsaicinoid concentrations than that of bacteria. Bacterial communities from four different chili pepper varieties showed significant differences in the enrichment of genera. Fungi were differentially enriched in two groups: the td1 group with high capsaicin concentrations and the sylj group with low capsaicin concentrations. Among the four groups, endophytic bacteria exhibited the highest percentage of genes associated with unknown functions, while fungal trophic patterns had the most significant percentage of unknown trophic types. Overall, this study provides a valuable reference for the efficient cultivation and utilization of industrial chili peppers in Tibet.

Actinobacteria play major roles in human health and soil nutrient biogeochemical cycles, which are important for environmental protection. On the northern Qinghai–Tibet Plateau, the Qiangtang Alpine Grasslands have recently become degraded to varying degrees due to global climate changes and human disturbances. Here, we compared the community diversity, composition, and potential metabolic functions of Actinobacteria in soil from different degradation conditions through Illumina MiSeq sequencing. The soil Actinobacteria community structure in the Qiangtang Alpine Grasslands of northern Tibet was dominated by Nocardioides, Gaiella, Solirubrobacter, and Pseudonocardia, with evidence of previously unidentified taxa. Compared with non-degraded and severely degraded grasslands, the moderately degraded grassland had the highest soil Actinobacteria alpha-diversity, and the community composition showed significant differences between degraded grasslands with different degrees of degradation. The interactions between Actinobacteria and KO functions predominantly show negative correlations, but significant positive correlations outnumber significant negative ones. This study showed that Actinobacteria diversity and potential ecological functions in the alpine grasslands of northern Tibet decreased with grassland degradation due to the loss of vegetation cover. Therefore, it is necessary to effectively manage and protect the Qiangtang Alpine Grasslands on the northern Tibetan Plateau.