Clonality is the ability of an organism, in natural conditions, to spontaneously produce independent or potentially independent offspring with the same genotype as their parents via clonal growth or clonal reproduction. Plants that possess clonality are clonal plants. They are ubiquitous in various types of ecosystems and dominate many ecosystems such as grasslands, tundra, wetlands and bamboo forests and play vital roles therein. Therefore, exploring clonal plants’ responses to and effects on changing environments and then their adaptive significances can deepen our understanding of the key processes and factors determining ecosystem composition, structure, functions and services, and help establish reliable natural solution-based ecosystem conservation and restoration techniques and programs. Starting from concept of plant clonality and clonal traits and in conjunction with over 40 years of progress in clonal plant ecology, we systematically tease out ecological responses of clonal plants to environmental changes, review the effects of clonal plants on ecosystems’ composition, structure, functions and services, and summarize basic and applied aspects of clonal plant ecology in the background of sustainable development. Finally, we propose future research directions of clonal plant ecology: using trait-based response-effect approach as new paradigm for clonal plant ecology/plant clone ecology; conducting clonal plant research in the context of vital eco-environmental challenges such as global climate change, land degradation, environmental pollution, biological invasion, and biodiversity loss; answering clonal plant ecology, plant clone ecology and and other-related scientific questions, at multiple organizational levels from individual to ecosystem; strengthening clonal plant research at the level of community/ecosystem; exploring phylogenetic pattern and molecular evolution process of plant clonality.

Changes in belowground ecological processes in the context of global change have become one of the hot issues of concern in the field of ecology. Mycorrhiza are symbiotic relationships between plant roots and mycorrhizal fungi, widely distributed in terrestrial ecosystems. As two major types of mycorrhizal fungi related to trees, arbuscular mycorrhizal fungi and ectomycorrhizal fungi exhibit significant differences in morphology and function. Root exudates, as an important medium for exchange of matter, energy, and information between plants and soil, play a crucial role in soil carbon dynamics. The root exudates of tree species associated with different mycorrhizal types can actively respond to environmental changes by continuously adjusting their quantity and chemical composition, and influence the belowground carbon dynamics and cycling processes of forest ecosystems. Currently, the composition and function of root exudates from different types of mycorrhizal fungi, as well as the variation and impact on plant and soil, remain unclear. Therefore, this article combines current frontiers in the field both domestically and internationally, and summarizes the root exudate characteristics, influencing mechanisms, and rhizosphere effects of tree species associated with different mycorrhizal types. This review is expected to provide references for further research on the response and adaptation mechanism of root systems and exudates to global changes. In addition, it also proposes directions for future research on root exudates among different types of mycorrhizal fungi that require further investigation: (1) strengthening systematic research on root exudates among different types of mycorrhizal fungi; (2) studying the influence mechanism of mycorrhizal type on root exudates in combination with other environmental factors; (3) using more precise technological means to comprehensively understand the changes in root exudate characteristics among different types of mycorrhizal fungi; (4) deeply revealing the influencing mechanism of root exudates among different types of mycorrhizal fungi from the perspective of plant physiology and metabolism; (5) conducting long-term dynamic monitoring and simulation experiments on different types of mycorrhizal fungi to predict their impact on soil ecological processes.

In the context of carbon sequestration, emission reduction, and the “Dual Carbon” goals, the impact of climate change characterized by the combined effects of elevated atmospheric carbon dioxide (CO₂) concentration and global warming on the dynamics of soil organic carbon (SOC) has emerged as a critical research focus. Understanding the mechanisms through of climate change influences SOC pools remains a significant challenge in academic research. Previous studies on the effect of climate change on terrestrial ecosystem carbon cycling have predominantly examined single factors, such as increased CO₂ concentration or warming, with a focus on plant growth, litter substrate quality, soil physicochemical properties, physical/chemical fractions of organic carbon, and microbial community structure. Building on recent advancements in both domestic and international research, this review synthesizes the effects and underlying mechanisms of elevated CO₂ concentration and warming on SOC accumulation. By integrating the coupling effects of SOC fractions, molecular composition, structural characteristics, and the differential responses of topsoil and subsoil, we elucidate the intrinsic mechanism governing SOC carbon accumulation and transformation under these climatic conditions. Furthermore, we highlight key areas for future research, including (1) clarifying the coupling relationships among SOC end-member inputs, molecular composition, and structural characteristics, and (2) uncovering the mechanisms by which long-term climate change influences the stability and burial potential of SOC across diverse ecosystems. To fully understand the carbon source/sink functions of soil, it is essential to comprehensively investigate the biogeochemical processes governing SOC sources, transformation, burial, and decomposition in terrestrial ecosystems under climate change. This review aims to provide a robust scientific foundation for future soil carbon management strategies and decision-making in support of carbon neutrality goals.

Aims The grasslands of Mongolian Plateau are the core of the Eurasian grassland ecosystem and serve as an important ecological barrier in northern China. Climate change has significantly increased the intensity, frequency, and duration of drought events across the Mongolian Plateau. Therefore, assessing the resistance and resilience of the Mongolian Plateau grasslands quantitatively helps deepen our understanding of their responses to climatic anomalies. However, few studies have explored how different grassland types on the Mongolian Plateau withstand consecutive droughts.
Methods In this study, we used long-term series data from 2000 to 2020 on the standardized precipitation evapotranspiration index (SPEI) and net primary productivity (NPP) to quantify the resistance and resilience of the Mongolian Plateau grassland ecosystem to consecutive droughts (1-4 a) and analyze its spatiotemporal variations. Furthermore, we compared the responses of three main types of grasslands (meadow steppe, typical steppe, and desert steppe) to extreme and moderate droughts.
Important findings Our results show that: (1) Grasslands generally exhibit higher resistance under moderate drought compared to extreme drought, except during two consecutive drought years. However, they are more resilient to extreme drought. (2) As the number of consecutive drought years increases, the resistance declines for both extreme and moderate droughts, while resilience initially increases under extreme drought but decreases under moderate drought. (3) Along the spatial gradient of decreasing precipitation, meadow steppe exhibits the highest resistance, followed by typical steppe, while desert steppe shows the lowest resistance. In contrast, desert steppe demonstrates the highest resilience, whereas meadow steppe has the lowest resilience. (4) Over time, the resistance of grasslands was higher from 2011-2020 compared to 2001-2010, while resilience was lower in the later period. As consecutive drought years increase, the resistance for all types of grasslands declines in both periods (2000-2010 and 2011-2020), while resilience initially increases (2000-2010) and then decreases (2011-2020). These insights are crucial for maintaining the Mongolian Plateau’s ecological barrier, ensuring its ecological services, and supporting both regional and global ecological security and sustainable development.

Aims The accumulation of nutritional components in plants is critically linked to their survival capacity and productivity. Investigating how arbuscular mycorrhizal fungi (AMF) inoculation regulates drought tolerance in plants through nutrient component changes in various organ will establish a theoretical framework for applying AMF to improve crop resilience under water-limited conditions.
Methods The study employed a controlled pot experiment with two water regimes (75% vs. 55% field capacity) and AMF inoculation treatments, using oat (Avena sativa) cultivar ‘Bayou 1’. Mycorrhizal colonization rates were quantified at jointing and filling stages, followed by analysis of non-structural carbohydrates (NSC), carbon (C), nitrogen (N), phosphorus (P) contents in root, stem, and leaf. Grain yield was recorded at the maturity stage.
Important findings In oat plants inoculated with AMF under drought stress, the AMF colonization rate, plant height, and root-to-shoot ratio were significantly enhanced, resulting in 13.31% increase in grain yield. Notably, these improvements in growth parameters and yield exceeded those observed in AMF-inoculated plants under well-watered conditions. Furthermore, AMF inoculation under drought stress increased soluble sugar accumulation in stem and leaf. Concurrently, the contents of C, N, P in root, stem, leaf, as well as the leaf C:N significantly increased, especially the contents of P in leaf. In contrast, the leaf N:P significantly declined. Redundancy analysis revealed that the contents of leaf soluble sugars, and stem C, root N contents served as key indicators explaining variations in growth traits and grain yield under drought stress and AMF inoculation, respectively. Overall, AMF inoculation under drought conditions enhanced oat drought tolerance and hence improved grain yield, primarily attributed to increase AMF colonization rate, which facilitated synergistically the accumulation of soluble sugar and C, N, P in organs, and modulated the leaf stoichiometric ratios (C:N and N:P).

Aims Smart agriculture requires real-time monitoring of crop growth and accurate yield prediction. In this study, we aim to investigating the capacity for using multiple phenological indicators from phenocam images to monitoring forage growth and predicting forage yield.
Methods Phenocam and unmanned aerial vehicle (UAV) images were taken during a one-year field experiment on the forage production of two forage species, silage maize (Zea mays) and oats (Avena sativa), under different fertilizer treatments. Based on the green chromatic coordinate (GCC) extracted from phenocam images, and the normalized difference vegetation index (NDVI) and leaf chlorophyll index (LCI) extracted from UAV images, we explored the capacity of using phenocams in tracking the growth status and estimating forage yield at the site scale.
Important findings (1) Nitrogen application rate affected the phenological metrics and harvest index of the forage grasses. The longest growing period ((68 ± 5) d) and the highest dry matter yield ((28 548.30 ± 4 269.30) kg·hm^-2) for silage maize were observed under high fertilizer treatment, while for oats, the longest growing period ((59 ± 1) d) and the highest dry matter yield ((5 180.70 ± 1 939.05) kg·hm^-2) were found under medium fertilizer treatment. (2) GCC and LCI showed high correlation with plant height. Before reaching the position of peak greenness (POP), GCC can well capture the dynamics of the plant height (R² was 0.86 for silage maize and 0.49 for oats), and had the smallest bias in capturing the plant height dynamics of silage maize. (3) The phenological indicators from phenocam can effectively predict forage yield (R² was 0.829 for silage maize, 0.935 for oat). This study confirmed that phenocam can effectively capture the dynamics of forage growth and predict yield. The phenological indicators from phenocam could provide an effective way for real-time monitoring of forage growth and for informing management practices.

Aims Intra-annual radial growth monitoring using the micro-coring method provides high-resolution and dynamic tree growth information, which is essential for understanding trees’ responses to climate change.
Methods In this study, we utilized the micro-coring method to monitor the seasonal growth dynamics of Pinus koraiensisand Ulmus davidianavar. japonicain the mixed broadleaf-Korean pine forest of Changbai Mountain.
Important findings Our comparative analyses revealed that: (1) The cell enlargement for U. davidianavar. japonica (day of the year (DOY) 116.0 ± 4.70) occurred earlier than that for P. koraiensis (DOY 125.0 ± 2.64), with both species showing a similar trend of initial increase followed by a decrease in cell enlargement length; (2) The growth rate peak for P. koraiensis occurred earlier than that for U. davidianavar. japonica, but the growth duration of U. davidianavar. japonica was longer than that of P. koraiensis. The average xylem growth rate of P. koraiensis was 3.4 μm·d^-1, with a maximum rate of 9.4 μm·d^-1, whereas for U. davidianavar. japonica, the rates were 11.0 and 23.0 μm·d^-1; (3) Both species exhibited highly consistent response trends to environmental factors, although U. davidianavar. japonica exhibited a less intense response to climatic factors compared to P. koraiensis. The radial growth lengths of both species showed significant positive correlations with mean, maximum and minimum air temperatures, relative humidity, and soil temperature, and significant negative correlations with photosynthetically active radiation and vapor pressure deficit. No significant correlations were observed with soil water content and precipitation. Temperature emerged as the primary climatic factor influencing radial growth of P. koraiensis and U. davidianavar. japonica throughout the year, with soil temperature being the most critical climatic factor.

This study aimed to investigate intraspecific variations in seed morphology and germination traits of Primula denticulataacross an elevational gradient in a mountain ecosystem, providing insights into ecological adaptations of plants to environmental changes.
Seeds from 13 P. denticulatapopulations were collected along an elevational gradient of 2 180-3 451 m in the Gaoligong Mountains of southwestern Yunnan in China. We measured a variety of seed traits, including length, width, width-to-length ratio, perimeter, area, biomass, optimum germination temperature (T_o), germination percentage (GP), mean germination time (MGT), variance in germination rate (VGR) and germination synchronization (GS) at the optimum temperature. Then, we tested relationships between these seed traits and elevation.
Results showed that: (1) Seed width, area and biomass of P. denticulata increased significantly with increasing elevation, while seed length, width-to-length ratio and perimeter were not significantly associated with elevation. (2) T_o and GS decreased significantly with increasing elevation, and MGT at T_o increased significantly with increasing elevation. No significant relationships were found between GP and VGR and elevation. (3) Elevation had a significant positive effect on seed width, area, and biomass, and variations in these morphological traits contributed to longer MGT and reduced GS along the elevational gradient. These findings show that the width and biomass of P. denticulata seeds increased with elevation, leading to delayed germination and lower synchronization, suggesting that high-elevation populations tend to adopt a “long bet” germination strategy.

Aims In-depth research on the hydraulic traits of plant xylem and leaf functional traits would be helpful to reveal their adaptation strategies to the environment, providing a theoretical basis for vegetation management and restoration.
Methods This study focuses on three typical shrub species in the mixed Pinus-Quercus forests of Beijing mountains areas: Vitex negundo, Grewia biloba, and Morus mongolica. Leaf functional traits (e.g., leaf area, net photosynthetic rate, leaf water potential, etc.) are determined through outdoor measurements and indoor experiments, while the xylem anatomical structure of the roots, stems, and branches of the three shrub species (e.g., vessel diameter, vessel density, etc.) is observed through sectioning, and hydraulic traits (e.g., specific hydraulic conductivity, hydraulic vulnerability index) are calculated, so as to understand the plant hydraulic structure and leaf functions and to reveal the adaptation strategies of these three shrub species to the shaded understory environment.
Important findings (1) Significant differences in leaf morphology, hydraulics, and functional traits were observed among the three shrubs; Vitex negundo had smaller leaf area but greater specific leaf mass, with the highest specific leaf mass and net photosynthetic rate; Grewia biloba had the largest vein volume but the lowest net photosynthesis and transpiration rates; Morus mongolica had the largest leaf area and midday leaf water potential. (2) Notable differences were found in the xylem vessel characteristics and hydraulic traits of the roots, stems, and branches of the three shrubs; Vitex negundo’s aboveground water transport efficiency exceeded that of its underground part; Grewia biloba maintained a balanced water transport efficiency across all xylem parts, with the strongest resistance to embolism; Morus mongolica maintained high water transport efficiency in all parts, with the weakest resistance to embolism. (3) Correlation analysis indicated that the xylem hydraulic traits of the three shrubs influence most of the variations in leaf structural traits and hydraulic traits. (4) Principal component analysis reveals that Grewia biloba tends towards a conservative slow strategy, Morus mongolica leans towards a water-consuming fast strategy, and Vitex negundo’s adaptation strategy lies between the former two.

Aims To comprehensively explore the physiological and ecological characteristics and adaptability of Rhododendron tomentosum in different forest types.
Methods This study investigated the physiological and biochemical characteristics and adaptability of R. tomentosum in four forest types (Betula platyphyllaforest, Larix gmeliniiforest, Pinus pumila forest and mixed coniferous broadleaf forest of B. platyphylla and L. gmelinii), and conducted a fuzzy evaluation for each forest type.
Important findings The results showed that different forest types had significant effects on the photosynthetic physiological characteristics of R. tomentosum. In B. platyphylla forest, R. tomentosum showed strong photosynthetic ability, high photosynthetic pigment content, high antioxidant enzyme activity, relatively high total polyphenols and total flavonoids content, and strong photosynthetic growth and stress resistance, indicating that R. tomentosum was better adapted to this forest type. In mixed coniferous broadleaf forest and L. gmelini forest, R. tomentosum had high volatile oil content, and the rest of the indexes were in the moderate level, and the thus adaptability was moderate. However, in P. pumila forest, the photosynthetic capacity of R. tomentosum was weak, the antioxidant enzyme activity was low, but its total polyphenols and total flavonoids and anthocyanins contents were high, which showed a certain degree of adaptability to adapt to the high alpine environment. This study provides a theoretical basis for the in-depth understanding of the growth pattern and adaptive mechanism of R. tomentosum under different forest types, and also provides theoretical support and practical guidance for the ecological protection, resource utilization and forestry production of R. tomentosum.

Aims Loquat (Eriobotrya japonica) is evergreen tree that often suffers photoinhibition or photodamage at low temperature in winter, which affects its growth. Therefore, this study explored the photoinhibition of two photosystems of loquat leaves in winter.
Methods In this study, the photoinhibition of two photosystems of loquat leaves in winter was compared using simultaneous measurements of chlorophyll fluorescence and 820 nm light reflection.
Important findings From autumn to winter, the maximum quantum yield of photosystem II (PSII) (F_v/F_m) in loquat leaves decreased significantly, while the photosynthetic electron transfer capacity at both the donor and acceptor sides of PSII did not change. The activity of photosystem I (PSI) did not change either. However, the actual photochemical efficiencies of both PSII and PSI decreased significantly. Non-photochemical quenching decreased significantly under high light. From winter to spring, the value of F_v/F_m in loquat leaves increased significantly. The electron transfer capacity at the acceptor side of PSII and the activity of PSI also decreased. Moreover, the actual photochemical efficiency of PSII increased significantly, while that of PSI remained unchanged. Non-photochemical quenching increased significantly under high light. These results indicate that the photoinhibition of PSI occurred later than PSII in loquat leaves in winter. The activity of PSI also recovered slowly. Photoinhibition of PSII occurred earlier, and its activity recovered earlier.

Aims Long-term grazing profoundly affects the external environment for plant growth and development in grassland ecosystems, and plants adapt to environmental changes through interactions with rhizosphere microbes. However, there is limited research on how grazing affects the rhizosphere microbial diversity of plants with different survival strategies in grasslands.
Methods In this study, based on a long-term grazing experiment on typical grasslands in Nei Mongol, we selected the dominant plant species Stipa grandis and Cleistogenes squarrosa as research subjects. Using high-throughput sequencing technology, we investigated the changes in rhizosphere bacterial diversity under different grazing intensities (control, light: 1.5 sheep·hm^-2, moderate: 4.5 sheep·hm^-2, and heavy: 7.5 sheep·hm^-2), and analyzed the differences in the responses of two dominant plant rhizospheric bacteria and their intrinsic connection with plant functional traits.
Important findings The results showed that: (1) Heavy grazing significantly reduced the rhizosphere bacterial richness (8.97%) and Chao1 index (9.48%) for Stipa grandis, but had no significant effect on the rhizosphere bacterial α-diversity of Cleistogenes squarrosa. Additionally, the α-diversity of Stipa grandis was significantly lower than that of Cleistogenes squarrosa. Moreover, heavy grazing significantly altered the bacterial community composition of both plant species, with the change being more pronounced in Stipa grandis than in Cleistogenes squarrosa. (2) As grazing intensity increased, Stipa grandiswas enriched with both plant growth promoting rhizobacteria and biocontrol agents, whereas Cleistogenes squarrosa was primarily enriched with plant growth promoting rhizobacteria. (3) Changes in the diversity and relative abundance of rhizosphere bacterial communities in Stipa grandiswere significantly correlated with its larger root diameter, lower specific leaf area, and lower specific root length, which reflect grazing avoidance and resource-conserving strategies. In contrast, changes in the bacterial communities of Cleistogenes squarrosa were significantly correlated with its higher carbon to nitrogen ratio in aboveground biomass and larger specific leaf area, which reflect grazing tolerance and resource-consuming strategies. In conclusion, this study demonstrated that the responses of rhizosphere bacterial communities of different dominant plant species to grazing pressure are closely related to their survival strategies, enriching our understanding of the synergistic adaptations between plants and rhizosphere microbial communities in the context of long-term grazing.