The development of carbon sequestration projects in plantation forests has the potential to offer win–win outcomes for the environment and economy. The Climate, Community, and Biodiversity (CCB) Standards ensure that a particular forest project will deliver tangible climate, community, and biodiversity benefits. According to the CCB Standards, it is necessary to assess community diversity in plantation forests. Our study provides indicators of community diversity based on Forest Integrity Assessment (FIA) according to the CCB Standards for carbon sequestration projects in Tianshui City, Gansu Province, China, which is located in the western Qinba Mountains. Herein, we estimated plantation forest conditions based on a forest condition assessment. Linear regression models were used to explore the relationships between FIA scores and community diversity (such as species richness, Shannon–Wiener index, inverse Simpson’s index, and Pielou’s evenness index quantified by species abundance) in plantation forests managed under carbon sequestration projects. The high community diversity reaches the CCB Standards. FIA scores were closely associated with Pielou’s evenness index of plant communities in plantation forests managed under carbon sequestration projects (R² = 0.104; mean square error = 0.014; standard error = 0.104; p = 0.012). A complex topography had positive effects on species richness, while a rich standing condition had negative effects on the Shannon–Wiener index. Forest conditions have been used as indicators of community diversity in plantation forests managed under carbon sequestration projects. The occurrence of climber and animal species should be used as indicators for enhancing community diversity to meet the CCB Standards. Furthermore, plant species richness benefits from a complex topography. However, our study had the limitation that the FIA could not cover the full range of environmental conditions. Our study provides a practical reference for applying the CCB Standards to plantation forests managed under carbon sequestration projects.

This study comprehensively analyzes the physical and chemical properties of soil across different layers under Salix paraplesia shrubs, comparing these properties inside and outside the shrub canopies. It also examines species diversity and community stability in these areas, discussing the impact of soil from resource islands at different formation stages on vegetation restoration. Focusing on Salix paraplesia shrubs over varying restoration periods (45 years, 25 years, and 13 years), with unrepaired mobile sandy land serving as the control, the results are as follows: (1) As vegetation restoration progresses, the content of soil organic matter (SOM) and alkali-hydrolyzable nitrogen (AN) significantly increase. After 45 years of restoration, SOM and AN contents are 250.08 % and 442.43 % higher than in the control. SOM, AN, and total phosphorus (TP) contents are greater under the shrubs than outside the canopies, indicating pronounced fertilizer accumulation. (2) The number of plant species increases during the restoration process, with 18 more species present after 45 years compared to the control. Community diversity is highest after 13 years of restoration, with greater overall diversity outside the canopies than under the shrubs. These differences decrease as restoration progresses. (3) The stability of Salix paraplesia shrub communities is higher outside the canopies compared to under the shrubs. As restoration proceeds, stability differences between these areas diminish. The Euclidean distances for community stability outside and under the canopies are 13.97 and 14.68, respectively, after 45 years, indicating relative stability. (4) In the early stages of restoration, soil carbon (C) and nitrogen (N) significantly impact species diversity, while in the later stages, phosphorus (P) content becomes more limiting. Resource islands enhance plant community stability and vegetation restoration, playing a crucial role in ecological protection and vegetation restoration in the alpine sandy land of the Yellow River's upper reaches.

This comprehensive dataset on the number of plant species, genera, and families in 383 national nature reserves in China has been compiled based on the available literature. Heilongjiang Province and the Guangxi Zhuang Autonomous Region have the highest number of nature reserves. Species richness is relatively high in the Jinfoshan, Dabashan, Wenshan, Hupingshan, and Shennongjia Nature Reserves. This dataset provides important baseline information on plant species richness coupling with genus and family numbers in Chinese national nature reserves and should help researchers and environmentalists understand the dynamic species changes in various nature reserves. This detailed and reliable information may serve as the foundation for future plant research in Chinese nature reserves and play a positive role in promoting more effective natural protection, biological distribution, and biodiversity conservation in these areas.