Styrax is a gorgeous species combined with high medicinal and ornamental values, however, information about its floral scents is limited. This study aimed to reveal the floral scent compounds and the dynamic changes in the flowering process of Styrax japonicus, S. grandiflora and S. calvescens. Static headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was adopted in the present study. The results showed that 24, 22 and 22 volatile compounds were present at three flowering stages, among which linalool, ocimene, α-pinene and germacrene D dominated in different species. Terpenes were the main floral scent compounds in all species, whereas there was considerable relative content of ketones in S. japonicus. Among the major terpenes, α-pinene, ocimene and myrcene were the common volatiles in these species, while β-elemene and allo-ocimene were the specific volatiles in S. japonicus and S. calvescens, respectively. The highest content of terpenes occurred at initial flowering stage in three species. The differences in the type and content of principal compounds contributed to the fragrance diversity among these species. A solid foundation for understanding the complexity of volatile emission could be obtained from our findings, meanwhile, effective utilization of abundant terpenes in flowers of Styrax species should be applied.

Background: The conventional fertilization regime ignores the allometric characteristics of Quercus nuttallii seedlings, challenging them to meet the nutritional needs at each growth stage. This study was conducted to determine the impact of exponential fertilization on the growth and nutrient status of Q. nuttallii container seedlings. Methods: Two fertilization regimes (average/exponential) were performed on Q. nuttallii container seedlings, and varied gradients (0, 300, 500, 700, and 900 mg/seedling) of N supply were set for the two regimes. Result: N application promoted the seedling height, root collar diameter, total biomass, and N/P/K accumulation of Q. nuttallii, and the exponential fertilization obtained better effects in general. An appropriate amount of exponentially N application was beneficial to the growth of root system, whereas excessive dosages inhibited it. Judging from seedlings growth status and nutrient accumulation, 900 mg/seedling under exponential fertilization was adequate for Q. nuttallii seedlings. However, 500 and 700 mg/seedling under exponential fertilization may have advantages in improving seedlings’ stress resistance. Conclusions: Exponential fertilization did not only meet the nutrient requirements and promote the growth of Q. nuttallii seedlings, but also facilitated the root growth to indirectly accelerate the assimilation of N/P/K, therefore improving the afforestation quality.

As the germ of a highly productive oil tree species, Styrax tonkinensis seeds have great potential to produce biodiesel and they have marvelous fatty acid (FA) composition. In order to explore the molecular regulatory mechanism of FA biosynthesis in S. tonkinensis seeds after methyl jasmonate (MJ) application, transcriptomic and metabolomic techniques were adopted so as to dissect the genes that are related to FA biosynthesis and their expression levels, as well as to discover the major FA concentration and composition. The results revealed that 200 μmol/L of MJ (MJ200) increased the crude fat (CF) mass fraction and generated the greatest impact on CF accumulation at 70 days after flowering. Twenty FAs were identified, among which palmitic acid, oleic acid, linoleic acid and linolenic acid were the major FAs, and the presence of MJ200 affected their concentrations variously. MJ200 could enhance FA accumulation through elevating the activity of enzymes that are related to FA synthesis. The number of differentially expressed genes increased with the seeds’ development in general. Fatty acid biosynthesis, the biosynthesis of unsaturated fatty acid, fatty acid elongation and glycerolipid metabolism were the main lipid metabolism pathways that were found to be involved. The changes in the expression levels of EAR, KAR, accA, accB and SAD2 were consistent with the changes in the CF mass fraction, indicating that they are important genes in the FA biosynthesis of S. tonkinensis seeds and that MJ200 promoted their expression levels. In addition, bZIP (which was screened by weighted correlation network analysis) also created significant impacts on FA biosynthesis. Our research has provided a basis for further studies on FA biosynthesis that is regulated by MJ200 at the molecular level and has helped to clarify the functions of key genes in the FA metabolic pathway in S. tonkinensis seeds.

Accurate quantification of terrestrial carbon dynamics is essential for assessing ecosystem–climate feedbacks and informing climate mitigation in the Anthropocene. China, as both the world’s largest emitter and a region of rapid ecological change, plays a key role in the global carbon cycle. Yet uncertainties in atmospheric forcing datasets remain a significant source of uncertainty in land surface model simulations and are rarely assessed systematically. Here, we assess China’s terrestrial carbon budget (1979–2014) using the Community Land Model (CLM _5.0 ) driven by three widely used meteorological datasets: CRUNCEP, the Global Soil Wetness Project Phase 3 (GSWP3), and the China Meteorological Forcing Dataset (CMFD), and evaluated against more than 800 FLUXNET site-months and nine eddy covariance towers. Forcing choice strongly alters the magnitude and trend of carbon fluxes, and China’s terrestrial ecosystems acted as either a weak carbon sink or a net source, depending on the forcing. GSWP3 performed best overall in simulating gross primary productivity (GPP), CRUNCEP relatively poorly, and CMFD best in high-altitude and cold-dry regions. Total ecosystem carbon storage was estimated at 86.30–90.00 PgC, primarily in soil (84.1%) and vegetation (15.9%). Interannual GPP variability was mainly controlled by precipitation (29.4%), followed by temperature (17.2%), while shortwave radiation had negative effects (11.5%). Shapley additive explanations analysis further showed that moisture-related variables (precipitation and humidity) dominate interannual GPP variability. By combining process-based modeling and machine learning, this study shows how uncertainties in meteorological inputs affect terrestrial carbon dynamics. These findings underscore the limitations of single-forcing simulations in Earth system modeling and highlight the need for improved meteorological inputs to support robust carbon budgeting and climate neutrality goals.

Forests deliver multiple essential ecosystem functions, and most natural forests occur in highly heterogeneous environments and span different developmental stages. Despite this complexity, the relative influences of biotic and environmental drivers on ecosystem multifunctionality (EMF) remain insufficiently understood across temporal and spatial scales. Here, we surveyed forests along elevational (1800–3500 m) and successional (early to late) gradients on the eastern Tibetan Plateau, quantify how climate, soil properties, and forest attributes (diversity, stand structure, and functional traits) regulate EMF. EMF was constructed from eight indicators representing nutrient cycling, plant productivity, and water conservation. Further, we assessed variation in biodiversity effects, including selection and complementarity effects. We found that soil moisture, functional diversity, and the coefficient of variation in stand diameter exert significant positive effects on EMF, whereas species richness—the most commonly used diversity metric—shows no significant effect. Mean annual temperature and soil bulk density, by contrast, have significant negative effects. The strengths of both selection and complementarity effects vary along elevational and successional gradients, with complementarity effects becoming markedly stronger at higher elevations. Overall, our findings reveal the mechanisms through which climate, soil properties, and forest attributes jointly regulate EMF, underscoring the pivotal roles of plant functional diversity and structural heterogeneity in sustaining the multifunctionality of subalpine forests. Results provide a robust empirical foundation for improving natural forest EMF and restoration management.