Mixed-species plantations are increasingly recognized for their potential to maintain forest biodiversity and soil health; however, a comprehensive assessment of their global effectiveness is lacking. To fill this knowledge gap, we conducted a meta-analysis of 7,045 paired observations between mixed-species and monoculture plantations, derived from 311 studies across diverse forest ecosystems worldwide. Our results show that mixed-species plantations significantly increased understory plant biomass, cover, and species richness by 32.6%, 55.4%, and 32.2%, respectively, compared to monocultures. Furthermore, the Shannon and Pielou diversity indices increased by 28.2% and 8.6%, respectively, and the Simpson index increased by 9.6%. When understory shrub and herbaceous species were considered separately, species mixing had significantly positive effects on shrub diversity but had no effect on herbaceous diversity. Moreover, mixed-species plantations markedly improved soil physical and chemical properties compared to monocultures. These improvements include increases in soil nutrient content (9.6 to 17.8%) and nutrient availability (14.7 to 33.5%), soil microbial biomass (17.2 to 28.8%), and soil carbon sequestration (7.2 to 19.9%). These enhancements were particularly pronounced in plantations that included legumes. Our findings reveal that the benefits of species mixing are influenced by climatic conditions, geographic location, and stand age, with the most substantial effects observed in temperate regions and mature stands. This study underscores the critical role of mixed-species plantations in promoting sustainable forest management and mitigating the ecological limitations of monocultures.

Davidia involucrata Baill. 1871 (D. involucrata), as a tertiary relict plant unique to China, is a national Class I protected plant with high economic value. Oil extracted from its seeds and peels can be used for both consumption and industrial purposes. It has become a popular income-earning export tree in China because of its graceful posture and beautiful white bracts. Climate change affects the distribution of the species’ potential habitat areas. Thus, studying its natural distribution pattern and future potential habitat distribution changes has great significance for the sustainable resource utilization and biodiversity conservation of D. involucrata. Here, we employed the MaxEnt model and ArcGIS software to predict the current and future (the 2050s and 2070s) potential habitats of D. involucrata via 130 species distribution records and 37 environmental variables. Meanwhile, we used the jackknife method to assess the importance of environmental factors. Our results showed the following: (1) When the RM = 4 and FC = LQHPT, the MaxEnt model exhibited the lowest complexity and overfitting degree while achieving high model prediction accuracy. The area under the curve (AUC) value of the simulated training was 0.958, indicating an excellent forecast. (2) Under the current climate scenario, D. involucrata was mainly concentrated in eastern Sichuan, western Hubei, northern Guizhou, and northwestern Hunan, with an area of 98.02 × 10⁴ km². (3) The precipitation in the warmest quarter (Bio18, 30%), mean temperature in the driest quarter (Bio9, 24.4%), annual mean radiation (Bio20, 14.6%), and elevation (ele, 12.7%) were the main environmental factors affecting its habitat distribution; the t contribution was 82.1%. (4) Under different future climate scenarios, the potential habitat area of D. involucrata decreased overall. Compared with the current climate scenario, the areas of potential habitats gradually decreased in both the 2050s and 2070s under the ssp126 and ssp585 climate scenarios but decreased in the 2050s and then increased in the 2070s under the ssp370 climate scenario. Therefore, it is of great significance to track and monitor the existing population or community on the basis of the possible changes in its distribution area. Moreover, the artificial breeding of its seedlings should be considered in the future to improve the quality of its germplasm resources. In summary, our findings can provide a scientific understanding of D. involucrata distribution in China and are conducive to conservation and utilization.

Acer truncatum Bunge and Xanthoceras sorbifolium Bunge are small deciduous trees distributed in East Asia and have high ecological and nutrient value due to their strong environmental adaptability and seed oil abundant in nervonic acid and unsaturated fatty acids. However, their natural distribution remains unclear, which will also be affected by the changing climatic conditions. The main purpose of this study was to map and predict the current and future potential suitable habitats of these two species using MaxEnt based on the presence location of species and environmental variables. The results showed that A. truncatum was more suitable for warm and humid climates and was more durable to climate change compared to X. sorbifolium. Under the current environmental conditions, the suitable habitat of A. truncatum was mainly concentrated in Inner Mongolia Plateau, Loess Plateau, Sichuan Basin, Northeast Plain, North China Plain, Korean Peninsula, as well as Japan, with an area of 115.39 × 10⁴ km². X. sorbifolium was mainly distributed in Inner Mongolia Plateau and Loess Plateau with an area of 146.15 × 10⁴ km². Under future climate scenarios, the model predicted that higher concentrations of greenhouse gas emissions could result in greater expansion of the potential distribution of both species. Meanwhile, the study also revealed that the two species migrated to the north by east to varying degrees with the change in suitable habitats. This work could provide scientific basis for resource protection and utilization of the two economic forest trees.

Moso bamboo ( Phyllostachys edulis ) expansion threatens subtropical forest biodiversity, yet how intraspecific root trait variation shapes rhizosphere microbial functional potential remains unclear. We aimed to elucidate how bamboo root trait variation and rhizosphere soil properties jointly shape microbial functional gene profiles during expansion. We investigated paired pure bamboo forests (PBF) and mixed bamboo forests (MBF) at four elevations in subtropical China, integrating individual‐level root trait measurements, rhizosphere soil analyses and shotgun metagenomic profiling. Bamboo in MBF exhibited acquisitive root strategies with significantly higher specific root length (615.33 vs. 446.03 cm/g) and specific root area (156.06 vs. 122.86 cm ² /g), but lower root tissue density (0.32 vs. 0.39 g/cm ³ ) compared to PBF. PBF rhizospheres harboured significantly enriched nitrogen and phosphorus cycling genes, with co‐occurrence networks showing substantially higher connectivity in phosphorus metabolism (1520 vs. 788 edges). Structural equation modelling demonstrated that forest type shaped functional gene assembly primarily through soil property modification, with root traits exerting limited direct effects. These findings reveal that established bamboo stands develop self‐reinforcing microbial feedbacks through soil modification, creating functionally integrated rhizosphere communities with enhanced nutrient cycling potential. Expansion fronts, where these feedbacks are not yet established, offer a critical window for management intervention before positive feedbacks strengthen. Read the free Plain Language Summary for this article on the Journal blog.

Genus Paeonia L. has important economic values in ornamental, medicine and food. China is one of the distribution centers of Paeonia and the origin to all wild species of section Moutan . Nowadays, most tree peonies species are in danger of extinction, but their geographical distribution is still unclear, hindering further resource protection. In this work, based on comprehensive environmental data and long-term presence records, the maximum entropy (MaxEnt) model was used to predict the future potential distribution of two Chinese endemic and endangered species, Paeonia decomposita and Paeonia rotundiloba. The results showed that the two species were narrowly distributed in Western Sichuan (Aba and Ganzi), China, with the temperature seasonality and UV-B seasonality being the most important environmental variables to determine the habitat suitability of the both tree peonies. In addition, growing degree days and precipitation seasonality also had an important impact on P. decomposita and P. rotundiloba, respectively. The reconstitution for the past distribution showed that they were mainly distributed in the south foot of Hengduan Mountain in the last interglacial (LIG) period. The reconstitution for historical suitable distribution indicated that the two tree peonies would migrated along Hengduan Mountain and Yarlung Zangbo River into the southeast of Qinghai Tibet Plateau, northeast from the current distribution. The areas of current potential distribution of the two tree peonies, which were partially crossed, were 14050 km 2 and 45299 km 2 respectively. Under different future climate scenarios, the potential distribution of the two peonies continued to expand and migrated to high-altitude areas in the north if the greenhouse gas concentration will continue to increase. This study will not only provide theoretical guidance for the conservation of P. decomposita and P. rotundiloba , but also help to understand the evolution and migration process of section Moutan.