Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020

Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.

An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana.In this study,we investigated the impact of invasive plants on the regeneration of forests dominated by K.evelyniana,a subtropical relict species in southwestern China.For this purpose,we characterized forest dynamics of 160 forest plots featuring K.evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K.evelyniana.We identified four distinct forest types in which K.evelyniana was dominant.We found that radial growth of K.evelyniana trees is faster in younger ageclasses today than it was for older trees at the same age.The population structure of K.evelyniana in each forest type exhibited a multimodal age-class distribution.However,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina adenophora.This invasive species resulted in a reduction of understory species diversity.Additionally,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern Yunnan.This suggests closely related invasive species face heightened competition,hindering successful invasion.Taken together,our findings indicate that successful establishment and habitat restoration of K.evelyniana seedling/saplings require effective measures to control invasive plants.

Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China

Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.

N-fixing tree species promote the chemical stability of soil organic carbon in subtropical plantations through increasing the relative contribution of plant-derived lipids

Biodiversity experiments have shown that soil organic carbon(SOC)is not only a function of plant diversity,but is also closely related to the nitrogen(N)-fixing plants.However,the effect of N-fixing trees on SOC chemical stability is still little known,especially with the compounding effects of tree species diversity.An experimental field manipulation was established in subtropical plantations of southern China to explore the impacts of tree species richness(i.e.,one,two,four and six tree species)and with/without N-fixing trees on SOC chemical stability,as indicated by the ratio of easily oxidized organic carbon to SOC(EOC/SOC).Plant-derived C components in terms of hydrolysable plant lipids and lignin phenols were isolated from soils for evaluating their relative contributions to SOC chemical stability.The results showed that N-fixing tree species rather than tree species richness had a significant effect on EOC/SOC.Hydrolysable plant lipids and lignin phenols were negatively correlated with EOC/SOC,while hydrolysable plant lipids contributed more to EOC/SOC than lignin phenols,especially in the occurrence of N-fixing trees.The presence of N-fixing tree species led to an increase in soil N availability and a decrease in fungal abundance,promoting the selective retention of certain key components of hydrolysable plant lipids,thus enhancing SOC chemical stability.These findings underpin the crucial role of N-fixing trees in shaping SOC chemical stability,and therefore,preferential selection of N-fixing tree species in mixed plantations is an appropriate silvicultural strategy to improve SOC chemical stability in subtropical plantations.

Caulerpa J. V. Lamouroux (1809) (Chlorophyta: Bryopsidales) Species and Sites in Eastern Samar, Central Philippines

A descriptive survey was conducted in Eastern Samar to identify the Caulerpa species, sites where these species exhibit massive populations, and the most preferred edible species. Results revealed that only four of the eleven species, C. racemosa, C. lentillifera, C. chemnitzia var. peltata, and C. cylindracea, have massive populations;The four Caulerpa sites are the municipalities of Arteche, Guiuan, Salcedo (Matarinao Bay) and Quinapondan, and species C. racemosa, C. lentillifera, and C. chemnitzia var. peltata are most preferred edible species which are considered in the local diet. The study concludes that the distribution of Caulerpa in Eastern Samar is area-specific and should therefore be considered in resource planning and management, particularly in relation to aquaculture.

Shells in the cabinet:four new species of Tellinidae(Mollusca:Bivalvia:Tellinoidea)identified from existing South China Sea collections

Four species new to science were identified in the Tellinidae museum collections in the Marine Biological Museum of Chinese Academy of Sciences.Pinguitellina triquetra sp.nov.,collected in 1981,has not previously been described or reported.It differs from other Pinguitellina species by its trigonal shape,rose-colored valve interior,and deep and wide pallial sinus,which is confluent with the pallial line.Pinguitellina protuberangla sp.nov.has a broad and deep dorsal corner,short and straight posterodorsal margin,comparatively large adductor scars,depressed and fragile shells,and deep socket at the anterior edge of the right valve.Pinguitellina minuta sp.nov.was previously misidentified as Arcopella casta in China.It is a new species based on its unique characteristics,which include small,fragile,inflated,translucent,and triangularly ovate-shaped shells with acuminated and convex umboes.As the first species described in China within the genus Abranda Iredale,1924,Abranda xui sp.nov.has internal ligaments and thin,fragile,and translucent elliptical shells with fine radials on the surface.In this study,we reorganized the species currently contained in the two genera Pinguitellina and Abranda and created keys to the known species.We believe that numerous collected bivalve specimens have been overlooked in the South China Sea,and to date,mollusk has not been adequately sampled.Thus,further exploration and analysis are required to understand species diversity in this area.

Polypore funga and species diversity in tropical forest ecosystems of Africa,America and Asia,and a comparison with temperate and boreal regions of the Northern Hemisphere

Polypores play a cru cial role in energy recycling and forest regeneration in forest ecosystems.The majority of them are wood degraders;some are forest pathogens and others are ectomycorrhizal symbionts.The basidiocarps provide food and shelter for many organisms,mostly invertebrates,but also some vertebrates,as well as food and medicine for humans.Despite extensive research on the species diversity and phylogenetic relationships of polypores in recent years,there remains a lack of comprehensive understanding of their distribution patterns and species composition at the large scale.Checklists of polypores from the tropical zone,including tropical Africa,tropical America,and tropical Asia,were analyzed for species diversity,distribution patterns,major taxa,and nutritional modes.A total of 1,902 polypore species was found in the three regions,representing 8 orders,46families,and 250 genera of Agaricomycetes.The orders Polyporales(especially the family Polyporaceae)and Hymenochaetales(especially the family Hymenochaetaceae)had the most prolific taxa,with their species accounting for 93.4%of the total polypores listed.Each of 1,565(or 82.3%)of the total 1,902 species were found in only one of the three regions studied,and we treat them temporarily as"regional endemic species".Only 141species were shared among all three regions,accounting for a mere 7.4%.Tropical Africa and tropical America had the greatest number of shared species and the highest S?rensen similarity index(SC)value.Tropical forests had a higher species richness compared with temperate to boreal forests of the Northern Hemisphere,and in addition,also a higher proportion of white rot polypores compared to brown rot and ectomycorrhizal species.This study outlines the distribution patterns and species diversity of polypores in the world,shedding light on their ecological significance in diverse ecosystems.

Morphological and Molecular Data Revealed One New Species of the Short-legged Toads Brachytarsophrys Tian and Hu,1983(Anura,Megophryidae)from Yunnan,China

A new species of the genus Brachytarsophrys,named Brachytarsophrys wenshanensis sp.nov.,has been identified in southeastern Yunnan,China.This new species can be readily distinguished from other known congeners by both morphological criterion and molecular analysis of three mitochondrial gene segments:16S,COI,and Cytb.This classification is based on the following morphological characters:(1)medium body size(SVL 83.8–85.1 mm in two adult males);(2)enormous head,with head width nearly 1.2 times the length;(3)tongue pyriform,feebly notched;(4)non-meeting heels;(5)male lacking nuptial pad;(6)tibiotarsal articulation reaching angle of mouth when hindlimbs are extended forward alongside the body;(7)absence of outer metatarsal tubercle,inner metatarsal tubercle elliptic and approximately equal to first toe;(8)rudimentary toe webbing,webbing formula:Ⅰ(2–)–(2^(++))Ⅱ(2^(–))–(3^(++))Ⅲ(2^(½))–(4)Ⅳ(4^(+))–(2^(⅔))V;(9)lateral fringes narrow;(10)dermal ridge or glandular fold on dorsum absent;(11)pectoral glands distinct and irregular,femoral gland small.Our work increases the number of species within the genus Brachytarsophrys to 9.

A new species of Discostella guiyangensis sp.nov.(Bacillariophyta,Stephanodiscales)from Guiyang,China:morphology and phylogeny

We describe a new species of Discostella from Guiyang based on light and scanning electron microscopic observations,as well as molecular analysis.This species is morphologically distinguished from other species by a relatively smooth and slightly recessed central area with marginal striae of unequal lengths forked near the margin.Marginal fultoportulae and a single rimoportula are situated between every two costae or on the costae.Both morphological characters and the concatenated data of rbc L and SSU rDNA indicate that Discostella guiyangensis is a unique and new species.According to divergence time estimation analysis,Discostella guiyangensis is the oldest species among the Discostella species sequenced currently.In addition,we complement molecular data of Discostella asterocostata and Discostella stelligera.

Optimal Control for Age Distribution and Weighted Size Competitive Species in a Polluted Environment

In the paper,we study an optimal control for a system representing a competitive species model with fertility and mortality depending on a weighted size in a polluted environment.A fixed point theorem is applied to obtain the existence and uniqueness exhibited by a non-negative solution of above mentioned model.A maximum principle helps to carefully verify the existence of the optimal control policy,and tangent-normal cone techniques help to obtain the optimal condition specific to control issue.

The role of reactive oxygen species in gastric cancer

Gastric cancer(GC)ranks fifth in cancer incidence and fourth in cancer-related mortality worldwide.Reactive oxygen species(ROS)are highly oxidative oxygen-derived products that have crucial roles in cell signaling regulation and maintaining internal balance.ROS are closely associated with the occurrence,development,and treatment of GC.This review summarizes recent findings on the sources of ROS and the bidirectional regulatory effects on GC and discusses various treatment modalities for GC that are related to ROS induction.In addition,the regulation of ROS by natural small molecule compounds with the highest potential for development and applications in anti-GC research is summarized.The aim of the review is to accelerate the clinical application of modulating ROS levels as a therapeutic strategy for GC.

Impacts of Human Activities and Season on Species Diversity and Abundance of Butterflies in Mpanga Kipengere Game Reserve and Surrounding Farmlands, Tanzania

Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing disturbance due to human activities, which is putting many wildlife species, particularly larger mammals, at risk. To determine the impact of human activities on butterfly species diversity and abundance in the reserve and its surrounding areas, we conducted a study from November 2021 to October 2023. We collected butterfly data using transect walks and baited traps in two habitat types. Our study yielded 2799 butterfly Individuals ranging in 124 species divided into five families habitat, season, and anthropogenic factors are significant environmental variables influencing species diversity and abundance of butterflies. Therefore, it’s important to protect habitat and dry-season water for the conservation of invertebrates such as butterflies. Our study findings provide essential information for ecological monitoring and future assessment of the Mpanga/Kipengere Game Reserve ecosystem health.

Contemporary Asymmetric Genetic Introgression Between Two Pelophylax Species in Shanghai

Human disturbances are considered to break reproduction barriers among species.Significant increases in hybridization events have been reported among a large number of taxonomic groups in anthropogenic environments,providing novel insights into species evolution mechanisms and conservation management in the Anthropocene.The Eastern Golden Frog(Pelophylax plancyi)and BlackSpotted Frog(P.nigromaculatus)are two sympatric anuran species with a long history of mitochondrial genome introgression in highly urbanized continental East Asia.However,there is only limited understanding of the pattern of their contemporary hybridization and factors influencing their interspecific relationship under anthropogenic disturbances.Here,interspecific hybridization between P.plancyi and P.nigromaculatus at the population level was investigated in Shanghai.All except two haplotypes obtained from both species in Shanghai were mixed together,and located in the introgression clade,implying multiple ancient mitochondrial introgression events occurred in the populations of our study area.Asymmetric genetic introgression was detected by microsatellite markers,with 0.7%of P.plancyi and 14.6%of P.nigromaculatus identified as contemporary admixed individuals.Consistent with the trend of population density,higher genetic diversity of neutral microsatellite loci was found in the more abundant P.plancyi;however,variation in mitochondrial(Cyt-b)and nuclear(POMC)genes was higher in relatively rare P.nigromaculatus.The population density of P.plancyi and number of water patches within local habitats were significantly positively correlated with both occurrences and proportions of admixed individuals in the populations of P.plancyi and P.nigromaculatus.Considering the prevalent transformation of habitats in urbanized areas,these results imply that a high population density in isolated artificially altered habitats is likely to increase interspecific hybridization.Thus,population monitoring and improvement of landscape connectivity between habitats would be needed to control the intensity of interspecific hybridization between P.plancyi and P.nigromaculatus in anthropogenic-disturbed environments.

Impacts of Aggregation Methods and Trophospecies Number on the Structure and Function of Marine Food Webs

Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also the accuracy of models’outputs.Selection of aggregation methods and the number of trophospecies are the keys to study the simplification of food web.In this study,three aggregation methods,including taxonomic aggregation(TA),structural equivalence aggregation(SEA),and self-organizing maps(SOM),were analyzed and compared with the linear inverse model–Markov Chain Monte Carlo(LIM-MCMC)model.Impacts of aggregation methods and trophospecies number on food webs were evaluated based on the robustness and unitless of ecological net-work indices.Results showed that aggregation method of SEA performed better than the other two methods in estimating food web structure and function indices.The effects of aggregation methods were driven by the differences in species aggregation principles,which will alter food web structure and function through the redistribution of energy flow.According to the results of mean absolute percentage error(MAPE)which can be applied to evaluate the accuracy of the model,we found that MAPE in food web indices will increase with the reducing trophospecies number,and MAPE in food web function indices were smaller and more stable than those in food web structure indices.Therefore,trade-off between simplifying food webs and reflecting the status of ecosystem should be con-sidered in food web studies.These findings highlight the importance of aggregation methods and trophospecies number in the analy-sis of food web simplification.This study provided a framework to explore the extent to which food web models are affected by dif-ferent species aggregation,and will provide scientific basis for the construction of food webs.

Effects of Flowering Mode and Pollinator Sharing on Reproductive Success in Natural Hybrid of Two Epimedium(Berberidaceae)Species

Mediated by pollenflow,natural hybridization is deemed a crucial factor that propels speciation infloral plants.Despite the fact that the diversity of Epimedium species is concentrated mainly in Southwestern China,the poten-tial impact of interspecific pollination on natural hybridization has yet to be empirically scrutinized.To explore this,we studied theflowering period and the visitors offlowers in three frequently overlapping Epimedium species at Jinchengshan National Forest Park,located in Nanchong,Sichuan Province.Additionally,we performed a ser-ies of pollination experiments to examine breeding systems and hybrid compatibility.Morphologically,Epime-dium pubescens and Epimedium wushanense are clearly distinct and easily recognizable byflower morphology,while the putative hybrid is morphologically intermediate between them.Our observation revealed that E.pub-escens and E.wushanense had 15 days of overlapping anthesis.Both species are self-incompatible and require pol-linator services for successful reproduction.Although their pollinators differ in quantity and species,Lasioglossum sp.(Hymenoptera:Halictidae)visited all three species.Artificial pollination revealed no breeding barriers among the three species,and the resulting hybrid seeds exhibited fertility.The overlapping time offlowering,commonfloral visitors,and compatibility of hybrids may be important factors contributing to successful interspecific pol-lination and speciation for natural hybrid species of E.pubescens and E.wushanense.Consequently,the role of potential interspecific pollination is crucial for hybrid speciation and the evolutionary dynamics of Epimedium species.

Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

Microarrow sensor array with enhanced skin adhesion for transdermal continuous monitoring of glucose and reactive oxygen species

Conventional blood sampling for glucose detection is prone to cause pain and fails to continuously record glucose fluctuations in vivo.Continuous glucose monitoring based on implantable electrodes could induce pain and potential tissue inflammation,and the presence of reactive oxygen species(ROS)due to inflammationmay affect glucose detection.Microneedle technology is less invasive,yet microneedle adhesion with skin tissue is limited.In this work,we developed a microarrow sensor array(MASA),which provided enhanced skin surface adhesion and enabled simultaneous detection of glucose and H_(2)O_(2)(representative of ROS)in interstitial fluid in vivo.The microarrows fabricated via laser micromachining were modified with functional coating and integrated into a patch of a three-dimensional(3D)microneedle array.Due to the arrow tip mechanically interlocking with the tissue,the microarrow array could better adhere to the skin surface after penetration into skin.The MASA was demonstrated to provide continuous in vivo monitoring of glucose and H_(2)O_(2) concentrations,with the detection of H_(2)O_(2) providing a valuable reference for assessing the inflammation state.Finally,the MASA was integrated into a monitoring system using custom circuitry.This work provides a promising tool for the stable and reliable monitoring of blood glucose in diabetic patients.

Overexpression of PbrGA2ox1 enhances pear drought tolerance through the regulation of GA_(3)-inhibited reactive oxygen species detoxification and abscisic acid signaling

Drought stress is a devastating natural disaster driven by the continuing intensification of global warming,which seriously threatens the productivity and quality of several horticultural crops,including pear.Gibberellins(GAs)play crucial roles in plant growth,development,and responses to drought stress.Previous studies have shown significant reductions of GA levels in plants under drought stress;however,our understanding of the intrinsic regulation mechanisms of GA-mediated drought stress in pear remains very limited.Here,we show that drought stress can impair the accumulation of bioactive GAs(BGAs),and subsequently identified PbrGA2ox1 as a chloroplast-localized GA deactivation gene.This gene was significantly induced by drought stress and abscisic acid(ABA)treatment,but was suppressed by GA_(3)treatment.PbrGA2ox1-overexpressing transgenic tobacco plants(Nicotiana benthamiana)exhibited enhanced tolerance to dehydration and drought stresses,whereas knock-down of PbrGA2ox1 in pear(Pyrus betulaefolia)by virus-induced gene silencing led to elevated drought sensitivity.Transgenic plants were hypersensitive to ABA,and had a lower BGAs content,enhanced reactive oxygen species(ROS)scavenging ability,and augmented ABA accumulation and signaling under drought stress compared to wild-type plants.However,the opposite effects were observed with PbrGA2ox1 silencing in pear.Moreover,exogenous GA_(3)treatment aggravated the ROS toxic effect and restrained ABA synthesis and signaling,resulting in the compromised drought tolerance of pear.In summary,our results shed light on the mechanism by which BGAs are eliminated in pear leaves under drought stress,providing further insights into the mechanism regulating the effects of GA on the drought tolerance of plants.

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable information.However,the potential of GEE for forest resource management has not been fully exploited.To extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast China.Spectral and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant species.The results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source independently.Similarly,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was accurate.Including terrain factors and removing spatial correlation from NFRI sample points further improved the recognition accuracy.The optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,respectively.The high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant species.Visualizing the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change mitigation.Although forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been investigated.In this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,China.Our results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other regions.Furthermore,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species evenness.When we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast height.These findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in China.Notably,many natural forests in southern China are not fully stocked.Therefore,their continued growth will increase their carbon storage over time.