Interspecific plant–soil feedback (PSF)—the influence of soil conditioned by one plant species on another—is key to ecosystem processes but remains challenging to predict due to complex factors like species origin and phylogenetic relatedness. These aspects are underexplored, limiting our understanding of the mechanisms driving PSFs and their broader implications for ecosystem functioning and species coexistence. To shed light on the role of plant species origin and phylogenetic distance in interspecific PSFs, we conducted a greenhouse experiment with 10 native responding species and soils conditioned by 10 native and 10 exotic species resulting in 20 species pairs. These pairs represented a range of phylogenetic distances between both species, spanning up to 270 million years of evolutionary history since their last common ancestor. Conditioning by both native and exotic species reduced biomass production, with stronger inhibition observed for native-conditioned soils. Native-conditioned soils also exhibited lower phosphorus levels, higher basal and specific respiration, and greater cation exchange capacity, base saturation, and magnesium content compared to exotic-conditioned soils. Contrary to expectations, phylogenetic distance did not influence PSFs, regardless of conditioning species origin. Our findings suggest that co-evolution drives native plants to foster microbial communities with low carbon-use efficiency, highlighting soil biota’s critical role in PSFs. This advances our understanding of interactions between plant species origin and microbial communities and underlines the importance of microbial management for promoting native species and controlling invasives. The lack of phylogenetic distance effects aligns with prior studies, indicating evolutionary relatedness alone does not reliably predict PSF outcomes.

Fine root dynamics are crucial for terrestrial ecosystem productivity and nutrient cycling. However, the effects of nitrogen (N) deposition on fine root dynamics in temperate ecosystems remain poorly understood. In this study, we used a meta-analysis to explore the general patterns and key drivers of fine root biomass and turnover in temperate forests and grasslands in response to N application. We found that N application significantly reduced fine root biomass compared to the control group (no N application), with notable differences across N forms. However, the impact of N application on fine root biomass remained consistent across ecosystem types, soil depths and root diameters. In terms of fine root turnover rate, N application had no significant overall effect, and the response did not vary across N forms, ecosystem types, soil depths or root diameters. However, significant differences were observed across methods for estimating fine root turnover rate. Multiple regression analysis showed that mean annual temperature (MAT) and experimental factors (including duration and N application rates) were the primary determinants of fine root biomass response to N application. In contrast, fine root turnover was not significantly influenced by any of the factors analyzed. Overall, our findings highlight the negative impact of N application on fine root biomass and the neutral effect on fine root turnover, and also suggest that find root dynamics are closely associated with experimental factors, including experiment duration and N application rate. This study provides an important advancement in understanding the feedback between root dynamics and global change, offering insights for developing management strategies to address belowground ecological processes under global change scenarios.

Ecological theories and field observations indicate a strong allometric relationship between plant biomass and leaf area. Here, we aimed to rigorously investigate how this allometry can predict the biomass responses to global warming. We conducted a global synthesis on a dataset of 188 species from warming experiments. The reliability of metabolic scaling theory (MST) and functional equilibrium theory (FET) was tested by estimating an allometric coefficient (β) under a Bayesian framework. The results showed that the high β in areas suffering low precipitation was consistent with both theories, while the high β in areas suffering low-temperature stress was consistent with the MST but not the FET. These differences in β between ambient and stressed environments might be derived from the hydraulic constraints in stressed environments. Using general allometry across all species explained 58% of the total variance in the warming responses of plant biomass. The predictive power was not largely improved when factors, such as plant functional type, mean annual temperature and precipitation, warming magnitude, and other experimental treatments, were considered. The predictive error was primarily due to the theoretical assumptions that are based on long-term adaptation failing to capture the changes in specific leaf area (SLA) under rapid global warming. Fortunately, integrating the information on plant traits such as SLA and leaf biomass fraction in the ambient environment effectively improved the predictive power from 58% to 81%, highlighting the necessity of incorporating plant traits into ecosystem models for better predicting the ecosystem carbon cycle in a changing world.

China represents a significant global hotspot for species in the family Fagaceae, which are widely distributed across the country and play a crucial role in various ecological and social systems. As the global cliamte is changing rapidly, predicting the future distribution and richness of these species in China holds substantial importance. This study presents the first national-scale assessment of the future distribution of 243 Fagaceae species in China, utilizing ensemble species distribution models (SDMs) for the 2050s and 2070s under various climate change scenarios. The SDM projections indicate notable changes in the distribution of Fagaceae species, characterizing with an overall decline in the distribution area, an upward migration in elevation and a northeastward shift in their range. These changes are expected to significantly alter the spatial pattern of species richness, creating possible refugia in the southwestern mountainous regions and the western Qinling Mountains. We further revealed that a considerable amount of China’s natural reserves will show decreased richness of Fagaceae under climate change. Our study systematically evaluates the impact of future climate change on the distribution of Fagaceae species in China, potentially helpful for conservation planning of these species in China.

During the restoration of degraded ecosystems, different shrub species often segregate along environmental water gradients. However, the physiological mechanisms driving this segregation remain unclear. To address this gap, we conducted a drought stress experiment (70%–80% field water holding capacity, CK; 40%–50% field water holding capacity, MD; 20%–30% field water holding capacity, SD) to explore the physiological mechanisms driving the dominance of different shrub species at various stages of ecosystem restoration. Salix gordejevii, a species dominant in the early stages of restoration with high water availability, and Caragana microphylla, a species dominant in the later stages under low water availability, were studied. The results showed that the living state index (LSI) of S. gordejevii was significantly lower than that of C. microphylla under drought stress (P < 0.05). Differences in plant hydraulics and water-use strategies explained how these species adapt to varying soil moisture conditions. Salix gordejevii employed a proactive water-use strategy with lower water-use efficiency (WUE) and reduced resistance to xylem embolism (xylem water potentials corresponding to 50% loss of conductivity, P₅₀), making it better suited to environments with more abundant water. In contrast, C. microphylla adopted a conservative water-use strategy. This strategy was characterized by increased WUE and enhanced resistance to drought-induced xylem embolism, which allowed it to thrive under more drought-prone conditions. Importantly, hydraulic efficiency (⁠K_leaf, K_s, and K₁) emerged as the primary determinant of living state in both S. gordejevii (47.30%) and C. microphylla (62.20%). The lower embolism resistance of S. gordejevii (⁠P₅₀ = 1.3 MPa) made it more susceptible to xylem cavitation, leading to a decline in hydraulic efficiency under SD. In contrast, C. microphylla’s higher embolism resistance (⁠P₅₀ = 2.3 MPa) enabled it to maintain stable hydraulic conductance across all drought treatments. These differences in hydraulic efficiency, driven by xylem embolism resistance, were key factors influencing shifts in shrub dominance during ecosystem restoration. These findings provide a physiological explanation for the replacement of shrub species during ecosystem restoration, where soil moisture is the main limiting factor.

Invasive alien species threaten global biodiversity and ecosystems. Understanding the context-dependency of invasion dynamics is crucial for uncovering the processes driving the establishment and spread of alien species. This study investigates how abiotic (soil characteristics) and biotic factors (resident vegetation diversity and similarity to the invader) affect the invasion success of Senecio inaequidens (South African ragwort) across high- and low-productivity habitats in northern Italy. Our results revealed that abiotic and biotic factors affect S. inaequidens success. We found evidence of biotic resistance from resident plant communities, driven mainly by diversity and cover. However, a negative relationship between S. inaequidens performance and both phylogenetic and functional similarity to resident species was found, indicating better performance when growing with more similar species. We additionally observed stronger resistance in more nutrient-rich environments, highlighting the context-dependent nature of such relationships. Our results suggest that S. inaequidens is more susceptible to competition than adverse abiotic conditions, making it as a good colonizer rather than a strong competitor. These findings emphasize the complexity of invasion dynamics and the importance of considering both biotic and abiotic factors in developing management strategies for invaded ecosystems.

Soil seed banks (SSBs) play an important role in the recovery and renewal of plant ecosystems. Numerous studies have explored the effects of grazing on the density, diversity, and composition of SSBs in grasslands. However, information on how different livestock species affect SSBs in semi-arid grasslands remains limited. Here we examined shift in species diversity, plant density, and community structure in both SSBs and aboveground vegetation in grasslands grazed by three livestock species under adaptive grazing management. We found that (i) Grazing by three livestock species increased plant density and species richness in both SSB and aboveground vegetation, with cattle grazing increased the most. (ii) Grazing leads to a notable increase in the seed density of annual and biennial plants while decreasing that of perennial plants in the upper 5 cm of soil; grazing also increases burial depth of seeds, with cattle and goat grazing significantly increasing the seed density of annual and biennial plants in the 5-10 cm soil layer, as well as that of perennial forbs in the 0-10 cm layer. (iii) The species composition of aboveground vegetation and SSB differed, but cattle grazing significantly increased the similarity between the two. Our results provide significant insights into SSB responses to three livestock species, and indicate that adaptive grazing management, which maintains grassland residual height above a certain level, may benefit the SSB and support vegetation regeneration.

The allocation of annual growth in biomass to primary plant organs is a central theme in ecology due to its role in developing ecological theories and agricultural applications. Classic theories have significantly improved our understanding of biomass allocation patterns influenced by various factors. However, increasing contrasting observations cannot be explained by classic theories. Recently, transient dynamic theory can resolve the problem. Here, we provide empirical evidence describing transient variations of biomass allocated to stems for four crop species (i.e. corn, soybean, flax, and wheat) in single and mixed systems. We show that plant ontogeny and increasing intraspecific competition promote variations in stem mass fractions. However, variations in stem mass fractions are reduced under strong interspecific competition. Plants with large total biomass have relatively stable stem mass fractions. These findings provide empirical foundations for integrating transient dynamics into general theoretical frameworks of biomass allocation patterns and may stabilize agricultural crop yields.

Unraveling the legacy effects of long-term climate warming is essential to for an integrated understanding of plant invasion success. However, knowledge regarding how these legacy influences invasive offspring and natural enemies remains lacking. This work was built on a long-term warming experiment established in 2012. Here, we selected invasive Solidago canadensis and performed a series of experiments to explore the effects of experimental warming on offspring S. canadensis from its native and invaded range, as well as the legacy effect of warming on three insect species, and three pathogens. The experience of long-term maternal warming facilitated the growth of offspring from invasive S. canadensis, regardless of the presence of insects or pathogens. This experience decreased insect growth when feeding on native S. canadensis, and inhibited pathogens when infecting invasive S. canadensis. Additionally, the presence of natural enemies could modulate the legacy effects of warming and population provenance. These results suggest that long-term climate warming could facilitate invasion success via coordinated increases in growth and defense, and that legacy effects of climate warming and maternal provenance are important for understanding the cascading effects of climate warming.

Compared to terrestrial plants whose diversity is more directly influenced by climate, aquatic plant diversity is considered to be more dependent on water environments. Therefore, it could be predicted that the phylogenetic relatedness of terrestrial plants is more susceptible to climate filtering than that of aquatic plants. We compiled a comprehensive distribution dataset of herbaceous angiosperms in China, including both terrestrial and aquatic species. We compared the phylogenetic relatedness and its environmental correlation of the two groups, using the standardized effect size of phylogenetic diversity (PD_ses) and the standardized effect size of mean phylogenetic distance (MPD_ses), which reflect shallow and deep evolutionary histories, respectively. We also use the deviation of PD_ses (ΔPD_ses) and MPD_ses (ΔMPD_ses) between terrestrial and aquatic plants to reflect differences in the phylogenetic relatedness between terrestrial and aquatic plants. Our results showed that the geographical patterns of PD_ses and MPD_ses between aquatic and terrestrial plants are roughly consistent. ΔPD_ses and ΔMPD_ses between terrestrial and aquatic plants vary across the geographical scale and environmental gradient. Environmental variables (current climate, historical climate change and topography) explained more of the variation in PD_ses and MPD_ses of terrestrial plants than that of aquatic plants, with the current climate explaining more of ΔPD_ses and ΔMPD_ses between terrestrial and aquatic plants. Our results reveal the differential impacts of large-scale environmental factors on the phylogenetic relatedness of terrestrial versus aquatic plant communities, providing a new perspective for understanding the ecological and evolutionary dynamics of these two distinct plant assemblages.

Studies on diversity–biomass relationships (DBRs) provide insights into the mechanisms underlying ecosystem functioning and services. While manipulative experiments indicate that both functional diversity and functional dominance influence biomass, with functional diversity often becoming the stronger predictor over time, their relative contributions during natural forest succession remain unclear. Here, we analysed tree data from 2010 to 2020 across early, middle and late-successional forests in subtropical China to investigate how the effect of taxonomic diversity on aboveground biomass (AGB) is related to shifts in the roles of functional diversity and functional dominance of five functional traits, corresponding to the complementarity and biomass ratio hypothesis. Our results showed that mean AGB increased with succession, reaching its highest at the middle stage. Taxonomic diversity influenced AGB primarily through its impact on functional properties rather than directly. From early to late-successional stages, functional dominance consistently emerged as the stronger predictor of AGB compared to functional diversity. Specifically, in earlier stages, the dominance of species with fast leaf economic traits directly and negatively impacted AGB, whereas, in the late stage, the dominance of tall species had a direct positive impact. Although functional diversity contributed increasingly to AGB in a positive manner during succession, its effect was primarily indirect, largely mediated through functional dominance. Overall, our findings support the biomass ratio hypothesis as the primary mechanism underlying DBRs throughout succession. This highlights the importance of functional dominance in driving forest biomass production and emphasizes the need to consider dominant species’ traits in forest management and restoration strategies.

Elevation changes may affect intraspecific relationships or interspecific relationships among species. However, previous studies on Quercus variabilis have rarely investigated how its population interactions vary with elevation and how the factors affect them. Here, we examined the species relationships in Q. variabilis natural secondary forests across the three different elevation ranges (lower, medium, and higher elevation areas) using the niche and the Hegyi competition method. As the elevation increased, Q. variabilis strengthened its dominant position, and the overall association between populations shifted from positive to negative, as evidenced by a significant decrease in the positive-to-negative correlation ratio from 0.45 (85/191) to 0.41 (80/196) and then to 0.32 (29/91), indicating that the interspecific relationship gradually transitioned from facilitation to competition. The ratios of the intraspecific competition index to interspecific competition index were 3.09, 8.92 and 6.82, respectively, indicating that Q. variabilis forests had greater intraspecific competition compared to interspecific competition, especially in the medium elevation area. The intraspecific and interspecific competition in the lower and medium elevation areas showed a decreasing trend with the increase of diameter class, while the competition among individuals in the higher elevation area became more stable. The SEM showed that soil properties were indirectly negatively correlated with the species competition through a significant negative effect on forest density, while community characteristics only had a significant negative effect on intraspecific competition. Our results demonstrated that elevation factors decreased the intraspecific and interspecific relationships within Q. variabilis forests, providing new insights into the effective conservation of Q. variabilis natural forests.

It is feasible for widely distributed mosses to monitor atmospheric nitrogen deposition in northern China, a global hotspot of atmospheric nitrogen pollution. Based on the nitrogen contents and nitrogen isotope values of mosses collected at Mengshan, Shandong Province in 2012, 2018 and 2022, we established a bottom-up method to calculate local atmospheric nitrogen deposition levels and source contributions. Moss nitrogen contents increased from 1.9 ± 0.2% in 2012 to 2.1 ± 0.4% in 2018, and to 2.4 ± 0.3% in 2022. On the contrary, moss nitrogen isotope values decreased from −7.5 ± 1.5‰ in 2012 to −8.6 ± 1.6‰ in 2018 and to −9.6 ± 1.3‰ in 2022. From 2012 to 2022, the total nitrogen deposition fluxes increased significantly (from 34.2 to 39.9 kg N ha⁻¹ yr⁻¹), especially the fluxes of ammonium-nitrogen deposition increased. Based on the results of Bayesian stable isotope analysis, volatilization-related ammonia (mainly from fertilizer applications and wastes) was predominant in ammonium-nitrogen deposition in the last decade. Fossil fuel nitrogen oxides contributed more than non-fossil fuel nitrogen oxides to nitrate-nitrogen deposition. Our results reveal that it is urgent to control volatilization-related ammonia and fossil fuel nitrogen oxides emission sources, which are the major contributors to atmospheric nitrogen deposition in the Mengshan area.

The north-south transitional zone in central China is a climatic and ecological sensitive area, and the southern margin of Pinus tabuliformis distribution, yet regional response to climate has not been investigated. Here, we developed different regional chronologies from 14 samplings along an east-west gradient in the Funiu Mountains. Correlation results indicated that regional tree growth was mainly limited by temperature and precipitation in May, especially for YM. Temperature in the south and precipitation in the north were significant limiting effects, except in LCM, where trees were more limited by temperature in the south than precipitation in the north. The limiting effect of temperature in May gradually weakened from east to west, while the effect of precipitation in May was higher in YM (east) and BB (west) than in LCM (middle), and the promoting effect of precipitation in the north was stronger than that in the south. The self-calibrating Palmer Drought Severity Index (scPDSI) had significant positive correlations with tree growth from April to June, with the highest correlation in May. Tree growth increased in the 1970s–80s and then decreased after the 1990s indicated that the growth had degraded under global warming. This result supports the ecological marginal effect theory of growth degeneration of P. tabuliformis in NSTZ under global warming. However, whole regional tree growth also showed stronger recovery and resilience under extreme drought, the resilience basically restored to the pre-disturbance level after three years, which is obviously contradictory with tree growth trend and needs to be further studied.

While substantial nitrogen (N) input from yak urine in intensively grazed grasslands on the Qinghai-Tibetan Plateau (QTP) is well documented, the species-specific responses of dominant forage plants—particularly regarding N uptake efficiency, environmental impacts, and associated microbial dynamics—remain poorly understood. This study investigated Elymus nutans (Gramineae) and Kobresia graminifolia (Cyperaceae), two ecologically dominant species, to elucidate the divergent nitrogen transformation features under urine deposition. During the growing season, we simulated yak urine input by applying 640 mL urine per 40 cm × 40 cm patch in natural grasslands. Over six weeks, we measured total plant N uptake and soil nitrous oxide (N₂O) emissions and evaluated soil nitrification rates through a 2-week indoor incubation experiment. To elucidate the underlying microbial mechanisms, we analysed the abundance and composition of rhizosphere ammonia-oxidizing archaea (AOA) and bacteria (AOB). Results showed that K. graminifolia exhibited significantly lower soil nitrification rates and N₂O emissions but higher total N uptake compared to E. nutans. Furthermore, K. graminifolia soil had lower AOB and higher AOA abundances. Specifically, the relative abundances of Nitrosophaera and Candidatus Nitrosocosmicus within AOA, as well as Nitrosovibrio and Nitrosomonas within AOB, were higher in K. graminifolia soil. These findings indicate that variations in nitrifier populations may be key drivers of differences in N uptake and N₂O emissions across dominant forage species. This study provides valuable insights for developing effective management strategies for intensively grazed grasslands on the QTP.

Plant reproductive phenology is sensitive to climate change and has great implications for plant reproduction, community structure and ecosystem functions. Shifts in reproductive phenology under warmer temperatures have been widely studied, but how other global change factors, such as nitrogen enrichment and altered precipitation, interact with warming to influence phenology remains poorly understood. We conducted a field experiment in a Tibetan alpine meadow to examine the effects of warming, nitrogen addition, precipitation reduction and their interaction on plant reproductive phenology in 2017 and 2021. We found that warming interacted with precipitation reduction to affect reproductive phenology, independent of nitrogen addition. Specifically, warming led to an advance in flowering (3.5 days) and fruiting onset (3.8 days), but precipitation reduction offset this effect. Warming also extended the duration of flowering and reproduction, but only when interacting with precipitation reduction. Nitrogen addition delayed the onset of flowering (2.1 days) and fruiting (1.8 days). Moreover, the effects of warming depended on the phenological niche of each species as well as its pollination mode. Early-flowering species advanced more in flowering onset than late-flowering species. The duration of flowering and reproduction of wind-pollinated species was prolonged while that of insect-pollinated species was shortened by warming. Our study highlights the necessity of considering the interaction of multiple factors in predicting phenological responses under global change and suggests that plant life-history traits should be taken into account in future studies.

The physiological response mechanisms of trees to climate change are complex, particularly across varying elevations and among different tree species. In this study, we collected tree ring samples from two dominant conifer species (Picea crassifolia and Pinus tabuliformis) at three elevations at the edge of the Tengger Desert. We used tree-ring width (TRW) and tree ring oxygen isotopes (δ¹⁸O_TR) to investigate how species and elevations affect their responses to climate change. Pearson's correlation analysis and relative importance analysis were used to study the specific response processes of the two conifers to climate. The results showed that the TRW was mainly controlled by SPEI during the growing season, which means that drought stress had the greatest effect on it. And δ¹⁸O_TR mainly responded to summer relative humidity (RH). Both TRW and δ¹⁸O_TR of Picea crassifolia showed higher sensitivity to climate change. This sensitivity is largely attributed to the rapid uptake of precipitation by its developed shallow-rooted root system, which allows it to retain the precipitation signal in both TRW and δ¹⁸O_TR. However, Picea crassifolia may be more susceptible to drought stress and growth decline or even death in the context of a warming region. Our results are important for understanding the impacts of climate change on forest ecosystems using multiple indicators and developing corresponding ecological conservation measures.