Leymus chinensis alliance, one of the most widely distributed communities in China’s temperate steppe, is a grassland vegetation type with the highest utilization value for animal husbandry. Investigating the distribution and community characteristics of Leymus chinensis formations can provide data for the management and restoration of natural grasslands. In this study, we investigated the characteristics of L. chinensis communities of 46 sites in Nei Mongol, including species composition, ecological characteristics, and community classification of L. chinensis alliance. A total of 187 vascular species, belonging to 109 genera and 37 families, were recorded. Asteraceae was the family with the most species, while Artemisia was the genus with the most species. Perennial herbs were the dominant life form, accounting for 71.66% of the total species. Xerophyte dominated the communities, accounting for 67.38% of the total species. The geographic composition of the system was dominated by the Eastern Palearctic species, followed by the Central Asian species. The L. chinensis alliance could be divided into 8 association groups, including Leymus chinensis - tussock, Leymus chinensis - semi-shrubby, Leymus chinensis - rhizome, Leymus chinensis - Carex, Leymus chinensis - annual/biennial, Shrub - Leymus chinensis, Leymus chinensis - bulbiferous herb and Leymus chinensis - forb and 26 associations.

Located in the northeast of the Qingzang Plateau, the Qaidam Basin is a huge plateau-type closed basin. The vegetation is dominated by desert, including swamp wetlands, halophytic meadows and montane grasslands. In order to show the species composition, community characteristics and distribution pattern of vegetation on the Qaidam Basin in more details, this study used the field data of the Second Tibetan Plateau Scientific Expedition and Research of 2022 and the Comprehensive Scientific Investigation of the Data-scarce Area of the Qinghai-Tibet Plateau of 2014, including 157 sample plots and 458 sample plots, which are integrated into the sample data set of plant communities in Qaidam Basin. Through the collation and compilation of data, a total of 185 species information was obtained, among which the families with the largest number of species were Asteraceae (39 species), Poaceae (33 species), Fabaceae (17 species), Amaranthaceae (16 species) and Brassicaceae (10 species), and the genera with the largest number of species were Stipa, Artemisia, Astragalus, Oxytropis and Saussurea. The composition of plant life forms is dominated by herbs, accounting for 78.37%. The species of middle Asia account for 41.62% of the geographical composition of the flora. Based on the phytocoenological-ecological principles, 157 sample plots can be classified into 4 Vegetation Formation Groups, 7 Vegetation Formations, 11 Vegetation Subformations and 40 Alliances. This data set can provide the most original basic data for the in-depth exploration of vegetation characteristics in the Qaidam Basin, the compilation and research of the Vegegraphy of China, and the mapping of the Qingzang Plateau and the national vegetation map.

The valley forest in the Ertix River Basin is the germplasm bank of Salicaceae species and has important genetic diversity value of Altay, Xinjiang, China. It is of great significance for the protection and utilization of precious resources to study the distribution of plant species and vegetation types under the current human activities such as climate change, hydropower project and grazing. In this study, 80 squares of 20 plots were investigated at 4-8 km intervals in the Burqin River, Haba River and Bilizik River. The constructive species, quantitative characteristics and diameter class structure of the community were analyzed, and the community types were classified. The results showed that: (1) 121 species, 92 genera and 34 families of plants were investigated in the main tributaries of the Ertix River Basin, with a large number of perennial herbaceous plants. (2) Betula pendula and Populus laurifolia were constructive species in the Burjin River and Haba River, while P. alba was constructive species in the Bilizik River. P. nigra, Populus × berolinensis var. jrtyschensis, and P. canescens are associated species, while Salix alba is mainly distributed alone along the riparian edge and rarely mixed with poplar species. (3) The number of individuals of the dominant tree species Betula pendula reached the maximum at the middle altitude of the three tributaries, while the number of individuals of Populus laurifolia was smaller at the middle altitude. (4) The diameter class structure of tree layer species was greatly affected by grazing in summer, and the individuals of large diameter class were the most, and the number of saplings and seedlings were less. (5) The valley forest communities were divided into 6 formations and 34 associations.

Dongtou National Marine Park (DNMP) locates at the southeast coast of China, and the climax vegetation belongs to the subtropical evergreen broadleaf forests. However, we are still unclear about the vegetation types on most islands in DNMP. The objective of this study is to investigate vegetation types and characteristics across islands in DNMP. We conducted vegetation survey by setting up 90 sampling plots on the islands in DNMP. Species composition and habitat information in each plot were recorded and vegetation type classification and naming were referred according to the Vegegraphy of China. A total of 3 Vegetation Formation Groups, 8 Vegetation Formations, 34 Alliances, and 80 Associations were found in DNMP. The widely distributed vegetation types included Pinus thunbergii evergreen needleleaf forest, Casuarina equisetifolia evergreen broadleaf forest, Acacia confuse evergreen broadleaf forest, Eurya emarginata evergreen broadleaf shrubland, and Eurya japonica evergreen broadleaf shrubland. Our finding provides basic and detail information of vegetation structure and composition in these continental islands in eastern China.

Nine uninhabited islands with different sizes, laying on the coast of Bohai Sea, were selected as research objects for a further understanding and study of the characteristics of plant communities. By using the method of sample plot survey, we investigated a total of 66 sample plots, covering the study of species composition, and the number of individuals, height and diameter at breast height (DBH) of woody plants, etc. 140 species of vascular plants belonging to 38 families and 98 genera were investigated through sampling plot method. The results showed that Asteraceae, Poaceae, Fabaceae were the most abundant families in the communities. Moreover, the native forest vegetation has been replaced by secondary ones dominated by Robinia pseudoacacia, Pinus thunbergii, Ailanthus altissima, and Ulmus macrocarpa, respectively. Meanwhile, temperate deciduous shrubland became zonal vegetation type in this area, and the representative communities are dominated by Ziziphus jujuba var. spinosa, Periploca sepium, Flueggea suffruticosa, Celastrus orbiculatus, respectively. And representative herbaceous alliances are dominated by Artemisia argyi, Suaeda salsa, A. capillaris, and Themeda triandra, respectively. In general, the species diversity of island plant communities is relatively low, belonging to vulnerable vegetation.

Arid and semi-arid ecosystem areas, which constitute an important component of the global land surface, act to regulate the long-term trend and interannual variations in global carbon and water cycles. Previous studies on the mechanisms underlying ecosystem carbon and water cycling and the development of relevant data products focus primarily on forest, grassland, and cropland ecosystems, with few research attention given to semi-arid shrublands. This research gap hinders the evaluation and projection of ecosystem functions at the regional scale. Since 2011, we used the eddy covariance technique to make continuous in situ measurements of carbon, water and heat fluxes in a shrubland ecosystem at Yanchi Research Station, the Mau Us Sandy Land. Data processing steps mainly included data collection, post-processing of raw data, quality control, gap-filling and carbon flux partitioning. We produced flux and micro-meteorological datasets at half-hourly, daily, monthly, and annual temporal resolutions for the years 2012-2016, and analyzed the overall quality of the datasets in terms of the proportion of valid data and the energy balance closure of flux measurements. Results showed: (1) After quality control, the proportion of valid data for half-hour net ecosystem CO₂ exchange (NEE), latent heat flux (LE), and sensible heat flux (Hs) was 56.23%-62.19%, 79.40%-94.12%, and 77.56%-91.27%, respectively. (2) Annual and monthly energy balance ratio ranged 0.78-0.83 and 0.59-1.19, respectively. (3) The energy balance closure estimated using the “ordinary least squares” regression method showed that the interannual and seasonal variations in the slope of regression curves varied with a range of 0.73-0.79 at interannual scale and 0.73-0.92 at seasonal scale, respectively. These results indicate that our datasets have a high proportion of valid data and a reasonable energy balance closure, and thus can be used in studies related to ecosystem processes and functions at varing spatio-temporal scales.

Caryopteris mongholica is a key protected wildflower plant distributed in typical steppe, desertified steppe and desert areas. But there is a lack of research on its community characteristics and classification. This paper aims to study the distribution, characteristics and classification of C. mongholica in northern China and provide a reference for further protection and management. From 2018 to 2021, a total of 40 representative C. mongholica sites were selected in northern China, and their community characteristics were studied using the sample plot survey method. Results showed: (1) Caryopteris mongholica is concentrated in the eastern, central and western of Nei Mongol Plateau, the northern Loess Plateau, Hexi Corridor, Qilian Mountains and other northwest temperate desert or steppe areas in China, and is often the dominant or associated species in the communities. (2) According to the survey of 40 sample sites, a total of 149 species of seed plants were recorded, belonging to 107 genera of 37 families, among which 31 communities with C. mongholica as construction or dominant species and 140 species of seed plants were recorded, mainly Compositae, Leguminosae and Gramineae. Among them, 39 species were shrubs, dwarf- and semi-shrubs, 76 species were perennial herbs and 24 species were annuals and biennials. In the classification of species presence, 87.94% were occasional species with frequency distribution less than 20%. Wide-range xerophytes occupied the advantage (63.12%) in the water ecological types. Middle Asia elements (26.24%) were the major floristic geographic elements. (3) Based on the life form and dominance of species, the 31 C. mongholica communities were divided into 3 association groups, C. mongholica - herb association group, C. mongholica + shrub - herb association group and C. mongholica + shrub association group, which were further subdivided into 19 associations. (4) Longitude and annual precipitation significantly influence the distribution of C. mongholica communities and species diversity.