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Questions: Trait–environment relationships hold great promise for elucidating the mechanisms that drive community assembly. We asked to what extent does functional trait coordination underlie the differentiation of acquisitive–conservative strategies along environmental gradients? Also, to what extent does soil water availability determine trait combinations and subsequently shape microhabitat preferences for species with distinct ecological strategies? Location: Yunnan Province, southwest China. Methods: Pearson correlation and trait network analyses were used to quantify trait associations. A combined RLQ–fourth‐corner analysis and a spatial autoregressive error model were employed to examine trait–environment relationships and explain species distribution along environmental gradients. Results: Leaf and stem traits were tightly coordinated along the first RLQ axis. Herein, traits representing construction cost exhibited trade‐offs against traits representing resource acquisition rate, underlying an acquisitive–conservative strategy differentiation along the environmental gradients. Significant overall and bivariate trait–environment relationships were found. In addition, the topographic wetness index contributed substantially to the environmental variation, and significantly influenced most traits alone. These results supported the hypothesis that soil water availability was the key environmental factor in selecting trait combinations and driving the differentiation of acquisitive and conservative strategies for coexisting species compared with other environmental factors. Finally, deciduous and a proportion of the evergreen species were acquisitive, whereas the remaining evergreen species were conservative, preferring wetter and drier microhabitats, respectively. Conclusions: Our findings indicate that soil water availability plays a central role in shaping both the trait combinations and microhabitat preferences of species with different ecological strategies rather than different leaf habits. These findings also highlight the fundamental significance of functional traits in facilitating the differentiation between acquisitive and conservative strategies along environmental gradients. [ABSTRACT FROM AUTHOR]

The ecosystem services (ES) can be influenced by various environmental factors. In order to efficiently allocate resources and manage ecosystems, it is important to understand the mechanisms by which these environmental effects impact the interactions and trade-offs among different ES. While previous studies have primarily examined the impact of individual environmental factors on ES, the intricate mechanisms underlying the effects of multiple environmental factors have been largely overlooked. In this study, we adopted a path analysis approach that considered interactions among explanatory variables. We analyzed multiple geospatial datasets from various sources, including remote sensing and climate data, to examine the main drivers—precipitation, temperature, FVC (fractional vegetation cover), NPP (net primary productivity), human activities, and altitude—affecting five ecosystem services: carbon sequestration service (C), habitat provision service (HP), soil conservation service (SCS), sand-stabilization service (SSS), and water conservation service (WCS) in arid and semi-arid mountainous regions. Our investigation found that all five ES have shown an upward trajectory over the past two decades. The most significant growth was observed in C, which increased by 39.4%. Among the environmental factors examined, precipitation has been identified as the predominant factor influencing the ES and the synergies and trade-offs among ES. The influence of precipitation on SCS reached a coefficient of 0.726. Human activity factors had the greatest influence on HP of the five ES with a path coefficient of 0.262. Conversely, temperature exhibited a suppressive influence on ES. The impact of factors such as NPP and altitude on ES was comparatively modest. Notably, human activities assumed a substantial contributory role in shaping the relationship encompassing WCS. It is worth noting that individual factors exerted differential effects on ES along distinct environmental gradients, including anthropogenic gradients. In this context, the combination of high altitude and substantial FVC demonstrated a notable contribution to WCS. Our study can provide valuable insights for the management of ES which can be utilized to optimize the regulation of the Loess Plateau Ecological Screen (LPES) ecological construction and promote regional sustainable development. [ABSTRACT FROM AUTHOR]

Aim: Mean lineage age is an important metric of evolutionary history and community structure of biological assemblages. Many studies have investigated geographic patterns and ecological drivers of mean lineage age in plant assemblages but all previous studies focused on vascular plants. Similar studies for bryophytes, a lineage of the oldest land plants, are lacking. Here, we fill this critical knowledge gap by investigating geographic patterns and ecological correlates of the mean genus age (MGA) of liverworts, a major lineage of bryophytes, in regional floras across China. Location: China. Taxon: Liverworts (hepatics, Division Marchantiophyta of bryophytes). Methods: MGA and its standardized effect size (MGAses) of liverworts in each of the 28 province‐level regions across China were related to 12 explanatory variables representing geography, contemporary climate and historical climate change, using correlation and regression analyses, and a variation partitioning approach. Results: We found that (1) MGA and MGAses of liverworts were correlated negatively with latitude and elevational range, and positively with mean annual temperature, and annual precipitation in the regions across China, (2) MGA and MGAses of liverworts were more strongly affected by temperature‐related variables than by precipitation‐related variables, and (3) MGA and MGAses of liverworts were more strongly affected by climate extremes than by climate seasonality. Main Conclusions: The relationships of mean lineage age with climatic condition in one of the oldest lineages of land plants (i.e. liverworts) are consistent with those in angiosperms, a relatively young lineage of land plants. Our study is the first to show that geographic and ecological distributions of the oldest land plants are generally consistent with the pattern frequently observed in angiosperms that biological assemblages in colder and drier climates have, on average, younger lineage ages. [ABSTRACT FROM AUTHOR]

Deep evolutionary histories can play an important role in assembling species into communities, but few studies have explored the effects of deep evolutionary histories on species assembly of angiosperms (flowering plants). Here we explore patterns of family divergence and diversification times (stem and crown ages, respectively) and phylogenetic fuses for angiosperm assemblages in 100 × 100 km grid cells across geographic and ecological gradients in China. We found that both family stem and crown ages of angiosperm assemblages are older in southeastern China with warm and humid climates than in northwestern China with cold and dry climates; these patterns are stronger for family stem ages than for family crown ages; families in colder and drier climates are more closely related across the family‐level angiosperm phylogeny; and family phylogenetic fuses are, on average, longer for angiosperm assemblages in warm and humid climates than in cold and dry climate. We conclude that the fact that deep evolutionary histories, which were measured as family stem and crown ages and family phylogenetic fuses in this study, have shown strong geographic and ecological patterns suggests that deep evolutionary histories of angiosperms have profound effects on assembling angiosperm species into ecological communities. [ABSTRACT FROM AUTHOR]

Aim: The plant economics spectrum provides a fundamental framework for understanding functional trait variation along environmental gradients. However, it is unclear whether there is a general whole‐plant economics spectrum across organs at the finer taxonomic scale (e.g. within genera), and if there is, which factors affect the trait coordination of the different organs. Here, we examined whether resource economics spectra of different organs (i.e. leaf, stem and root) can be integrated at the whole‐plant level within a single genus, and how environment, intraspecific variation and taxonomic scale shape the whole‐plant spectrum. Location: China. Time period: 2018. Major taxa studied: Artemisia. Methods: We sampled 1,022 individuals of 62 Artemisia species in central and eastern China to test trait coordination patterns from organ to whole‐plant level. From the resource economics spectrum perspective, 15 traits were chosen to represent the trade‐off between structural and nutrient investments, including organs' C, N, P and dry matter content, specific leaf area, specific stem length and specific root length. Results: Pairwise trait correlations and the trade‐off patterns along the resource economic axis were consistent at both organ and whole‐plant levels. Environmental gradients did not strongly affect the correlations among leaf, stem and root economics spectra, that is, the intraspecific variation weakened but did not mask this coordination. Taxonomic scale did not affect the degree of trait coordination as the genus‐wide whole‐plant economics spectrum also emerged within each of the three subgenera. Main conclusions: Our results support the hypothesis that the coordination of economics spectra across organs forms a whole‐plant economics spectrum representing a 'fast–slow' resource management strategy, which is robust to recent evolution (genotypic variation, even for species within a single genus) and present‐day environmental variation. Further studies should elucidate in which circumstances or phylogenetic branches the coordinated pattern found for Artemisia is representative of other widely distributed genera. [ABSTRACT FROM AUTHOR]

Identifying patterns and drivers of plant community assembly has long been a central issue in ecology. Many studies have explored the above questions using a trait‐based approach; however, there are still unknowns around how patterns of plant functional traits vary with environmental gradients. In this study, the responses of individual and multivariate trait dispersions of 134 species to soil resource availability were examined based on correlational analysis and torus‐translation tests across four spatial scales in a subtropical forest, China. Results indicated that different degrees of soil resource availability had different effects on trait dispersions. Specifically, limited resource (available phosphorus) showed negative relationships with trait dispersions, non‐limited resource (available potassium) showed positive relationships with trait dispersions, and saturated resource (available nitrogen) had no effect on trait dispersions. Moreover, compared with the stem (wood density) and architectural trait (maximum height), we found that leaf functional traits can well reflect the response of plants to nutrient gradients. Lastly, the spatial scale only affected the magnitude but not the direction of the correlations between trait dispersions and environmental gradients. Overall, the results highlight the importance of soil resource availability and spatial scale in understanding how plant functional traits respond to environmental gradients. [ABSTRACT FROM AUTHOR]

We aim to assess the influence of phylogenetic scale on the relationships of taxonomic and phylogenetic turnovers with environment for angiosperms in China. Specifically, we quantify the effects of contemporary climate on β‐diversity at different phylogenetic scales representing different evolutionary depths of angiosperms. We sampled a latitudinal gradient and a longitudinal gradient of angiosperm assemblages across China (each ≥3400 km). Species composition in each assemblage was documented. Three metrics of β‐diversity (βsim.tax measuring taxonomic β‐diversity; βsim.phy and Dpw measuring tip‐ and basal‐weighted phylogenetic β‐diversity, respectively) were quantified among assemblages at sequential depths in the evolutionary history of angiosperms from the tips to deeper branches. This was done by slicing the angiosperm phylogenetic tree at six evolutionary depths (0, 15, 30, 45, 60, and 75 million years ago). β‐diversity at each evolutionary depth was related to geographic and climatic distances between assemblages. In general, the relationship between β‐diversity and climatic distance decreased from shallow to deep evolutionary time slice for all the three metrics. The slopes of the decreasing trends for βsim.tax and βsim.phy were much steeper for the latitudinal gradient than for the longitudinal gradient. The decreasing trend of the strength of the relationship was monotonic in all cases except for Dpw across the longitudinal gradient. Geographic distance between assemblages explained little variation in β‐diversity that was not explained by climatic distance. Our study shows that the strength of the relationship between β‐diversity and climatic distance decreases conspicuously from shallow to deep evolutionary depth for the latitudinal gradient, but this decreasing trend is less steep for the longitudinal gradient than for the latitudinal gradient, which likely reflects the influence of historical processes (e.g., the collision of the Indian plate with the Eurasian plate) on β‐diversity. [ABSTRACT FROM AUTHOR]

Agricultural drainage ditches (ADDs) are ubiquitous and regarded as active zones for biogeochemical reactions and microbe-mediated pollutant removal. However, little is known about the microbial distribution and community assembly in ADDs. Here, a typical large-scale irrigation district, including five orders of farmland drainage systems (namely field, sublateral, head, branch, and trunk ditches that could efficiently remove excess water from paddy fields to downstream water bodies), was selected to investigate the ecological processes of microbial communities and N- and P-transformation processes in multistage ditches. We found that scale effects drove distinct environmental gradients and microbial community dissimilarities and that the five ordered ditches were grouped into three clusters (field vs. sublateral vs. head, branch, and trunk ditches). Specifically, the microbial communities in the field ditches located adjacent to the paddy fields were strongly selected by agricultural fertilization and irrigation drainage, enriching salt-tolerant microbes with high nitrification and inorganic P solubilization capabilities. In comparison, the sublateral ditches showed the highest removal performance for total nitrogen (13.28–55.80%) and total phosphorus (9.06–65.07%) during the growth of rice, which was mainly attributed to the enrichment of versatile microbiota (e.g., C39 , Nitrospira, and Novosphingobium) as a result of the increased stochastic processes driven by the low redox potential. Notably, the specific gene (i.e., hzsB) for anaerobic ammonium oxidation in sublateral ditches was 1–2 orders of magnitude higher than in adjacent ditches, further contributing to N loss. As field water was discharged into the large-sized head, branch, and trunk ditches, the nutrient levels decreased sharply. At the same time, deterministic processes gained more importance (∼82%), leading to the flourishing of Synechococcus and increasing the potential risk of eutrophication. Overall, the microbial communities in multistage ADDs were co-shaped by agricultural practices and ditch size, which further governed the N and P removal performance. These results provide unique insights into microbiota assembly patterns and dynamics in multistage ADDs and important ecological knowledge for controlling agricultural non-point source pollutants by managing of small-sized ditches. [Display omitted] • Microbial dynamics and their contributions to N and P removal were investigated. • Microbial communities in multistage drainage ditches were scale dependent. • Agricultural practices and ditch size co-shape the microbial communities in ditches. • Local heterogeneity enhanced stochastic process and enriched functional microbiota. • Multistage drainage ditches were efficient to control non-point source pollutants. [ABSTRACT FROM AUTHOR]

Aim: Understanding patterns and drivers of phylogenetic beta diversity in a region is important to understanding the origin and maintenance of the regional species diversity and variation in species diversity between local sites. Here we used a phylogenetic beta diversity metric quantifying deep evolutionary histories to explore geographical and ecological patterns of phylogenetic beta diversity in angiosperm assemblages across China. Location: China. Taxon: Flowering plants (angiosperms). Methods: China was divided into 100 × 100 km grid cells. Species composition in each grid cell was documented. We used a basal‐weighted metric (Dpw) to quantify phylogenetic beta diversity among angiosperm assemblages with two sampling approaches (neighbourhood approach and pairwise approach). Dpw was related to latitude and climatic conditions of angiosperm assemblages and to geographical and climatic distances between angiosperm assemblages across China. Results: We found that the southeastern portion of China has much higher Dpw than the northwestern portion of China. The line of high versus low values of Dpw across China is generally consistent with the line of 500‐mm precipitation per year. Our study shows that precipitation is associated with Dpw more strongly than temperature, and Dpw decreases with latitude, particularly in the eastern part of China. Main conclusions: The emergence of the observed pattern of basal‐weighted phylogenetic beta diversity is at least partly because the southeastern portion of China retains a large number of Tertiary relicts, making it a biogeographical museum, whereas many Tertiary relicts went extinct from the northwestern portion of China, particularly the Tibetan Plateau, due to the uplift of the plateau and the Himalayas, which makes the region a biogeographical grave for Tertiary relicts. [ABSTRACT FROM AUTHOR]

Biomass allocation patterns reflect the adaptive strategies of plants growing in different environments, which is a central issue in comparative plant ecology and evolution. However, the factors underpinning specific allocation patterns across organs and the existence of general rules governing allocation remain contentious. Optimal partitioning theory (OPT) states that plants can respond to resource availability by allocating relatively more biomass to the organ that captures the most limiting resources to optimize growth. In contrast, allometric partitioning theory (APT) postulates that biomass allocation among organs is a power function of plant size independently of environmental variation. As phylogenetic and growth form constraints (e.g. formation of inert heartwood in tree clades) may also affect biomass allocation, comparison among and within closely related taxa of rather similar growth form may enable a more direct testing of which of these two theories prevails.To test whether OPT or APT was prevalent at wide geographical scale, we investigated biomass allocation patterns among leaves, stems and roots of 1,022 plants of 62 Artemisia species (Asteraceae) collected along broad climate (annual mean temperature range: −4.9 to 18.0°C, annual mean precipitation range: 193–1,668 mm) and soil gradients (soil carbon content range: 1.6–15.4 kg C m−2) in central and eastern China.There were strong allometric relationships among leaf mass (ML), stem mass (MS) and root mass (MR) at both interspecific and intraspecific levels. Moreover, the interspecific and intraspecific patterns were not different from general patterns for pooled plants, that is, ML/MR and ML/MS, but not MS/MR, generally decreased with plant size. However, the three organ mass ratios were not responsive to broad climatic or soil gradients after the effect of plant size was removed.Synthesis. Our results generally support APT instead of OPT, suggesting that Artemisia plants have evolved an allometric strategy rather than relying on adjustment of allocation among organs to adapt to the broadly varying environments at the regional scale. For follow‐up research, we hypothesize that the strong allometric constraints on biomass allocation should depend on strong physiological adaptive responses of the different organs of Artemisia to environmental gradients. [ABSTRACT FROM AUTHOR]

A full understanding of the origin and maintenance of β‐diversity patterns in a region requires exploring the relationships of both taxonomic and phylogenetic β‐diversity (TBD and PBD, respectively), and their respective turnover and nestedness components, with geographic and environmental distances. Here, we simultaneously investigated all these aspects of β‐diversity for angiosperms in China. Specifically, we evaluated the relative importance of environmental filtering vs dispersal limitation processes in shaping β‐diversity patterns. We found that TBD and PBD as quantified using a moving window approach decreased towards higher latitudes across the whole of China, and their turnover components were correlated with latitude more strongly than their nestedness components. When quantifying β‐diversity as pairwise distances, geographic and climatic distances across China together explained 60 and 53% of the variation in TBD and PBD, respectively. After the variation in β‐diversity explained by climatic distance was accounted for, geographic distance independently explained about 23 and 12% of the variation in TBD and PBD, respectively, across China. Overall, our results suggest that environmental filtering based on climatic tolerance conserved across lineages is the main force shaping β‐diversity patterns for angiosperms in China. [ABSTRACT FROM AUTHOR]

Anthropogenic conversion of natural to agricultural land reduces aboveground biodiversity. Yet, the overall consequences of land‐use changes on belowground biodiversity at large scales remain insufficiently explored. Furthermore, the effects of conversion on different organism groups are usually determined at the taxonomic level, while an integrated investigation that includes functional and phylogenetic levels is rare and absent for belowground organisms. Here, we studied the Earth's most abundant metazoa—nematodes—to examine the effects of conversion from natural to agricultural habitats on soil biodiversity across a large spatial scale. To this aim, we investigated the diversity and composition of nematode communities at the taxonomic, functional, and phylogenetic level in 16 assemblage pairs (32 sites in total with 16 in each habitat type) in mainland China. While the overall alpha and beta diversity did not differ between natural and agricultural systems, all three alpha diversity facets decreased with latitude in natural habitats. Both alpha and beta diversity levels were driven by climatic differences in natural habitats, while none of the diversity levels changed in agricultural systems. This indicates that land conversion affects soil biodiversity in a geographically dependent manner and that agriculture could erase climatic constraints on soil biodiversity at such a scale. Additionally, the functional composition of nematode communities was more dissimilar in agricultural than in natural habitats, while the phylogenetic composition was more similar, indicating that changes among different biodiversity facets are asynchronous. Our study deepens the understanding of land‐use effects on soil nematode diversity across large spatial scales. Moreover, the detected asynchrony of taxonomic, functional, and phylogenetic diversity highlights the necessity to monitor multiple facets of soil biodiversity in ecological studies such as those investigating environmental changes. [ABSTRACT FROM AUTHOR]

Peatlands are a specialized type of organic wetlands, fulfilling essential roles as global carbon sinks, headwaters of rivers and biodiversity hotspots. Despite their importance, peatlands are being lost at an alarming rate due to human disturbance and climatic variability. Both the scientific and regulatory communities have focused considerable attention on developing tools for assessing environmental changes in peatlands. Diatoms are widely used in biomonitoring studies of lakes, rivers and streams as they have high abundance, specific ecological preferences and can respond rapidly to environmental change. However, diatom-based assessment studies in peatlands remain limited. The aims of this study were to identify indicator species and genus for three types of habitats (hummocks, hollows and ditch edges) in peatlands (central China), to examine the effects of physiochemical factors on diatom composition at genus and species levels, and to compare the efficiency of species- and genus-level identification in environmental assessment. Our results revealed that hummocks were characterized by drought-tolerant diatoms, while hollows were dominated by species and genus preferring wet conditions. Ditch edges were characterized by diatoms with different life strategies. Depth to water table, redox potential, conductivity and calcium were significant predictors of both genus- and species-level composition. According to ordination analyses, pH was not correlated with species composition while it was a significant factor associated with genus-level composition. Genus-level composition outperformed species composition in describing the response of diatoms to environmental variables. Our results indicate that diatoms can be useful environmental indicators of peatlands, and show that genus-level taxonomic analysis can be a potential tool for assessing environmental change in peatlands. [ABSTRACT FROM AUTHOR]

• 4300 km long transects were established in the ecologically fragile areas of China. • Soil C:N:P stoichiometry in ecologically fragile areas was well-constrained. • C:N:P stoichiometry differed among the areas in response to environmental changes. • Climate and vegetation factors were the key drivers of soil C:N:P stoichiometry. Researchers are paying increasing attention to soil stoichiometry (carbon:nitrogen:phosphorus (C:N:P) ratios) in efforts to explore biogeochemical cycles, but little is known about the spatial pattern, implications, and driving factors of this stoichiometry in large, ecologically fragile areas. To explore these factors, we established three transects that covered a total length of about 4300 km in ecologically fragile areas of China, and sampled at intervals of about 25 km. These transects covered the karst area and the agro-pastoral ecotone of southwestern China, the Qinghai-Tibet Plateau, the Loess Plateau, and the forest-grassland ecotone. We collected 312 soil samples to a depth of 30 cm from 156 plots. The soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) in the ecologically fragile areas showed strong coupling relationships. Soil C:N:P was 51:4:1 to a depth of 30 cm, which is lower than the average global C:N:P (111:8:1). SOC and TN concentrations at 0 to 20 cm were significantly higher than that at 20 to 30 cm, but TP did not differ significantly among depths. SOC, TN, and TP concentrations were highest in the agro-pastoral ecotone, and were lowest in the Loess Plateau. C:N, C:P, and N:P were highest in the karst area. C:N were lowest in the Qinghai-Tibet Plateau, and C:P and N:P were lowest in the Loess Plateau. The spatial pattern of C, N, and P stoichiometry along environmental gradients was variable. The contributions to explaining the soil stoichiometry were highest for climate (21.7%), vegetation (8.9%), soil properties (6.4%), and topography (0.6%) to a depth of 20 cm, versus vegetation (35.9%), climate (5.3%), soil properties (3.3%), and topography (2.1%) at 20 to 30 cm. The results provide new insights into the biogeochemical cycles of C, N, and P and guidance for their impacts on ecological restoration in ecologically fragile areas. [ABSTRACT FROM AUTHOR]

Carbon (C), nitrogen (N) and phosphorus (P) stoichiometries play critical roles in the function and structure of ecosystems by affecting important ecological processes. Yet, most studies to date have concentrated on foliar stoichiometry of phylogenetically distantly related species., Here, we hypothesized that (i) plant stoichiometry of closely related species still shows biogeographic patterns because of the geographic patterns of abiotic environment at the regional scale and (ii) even related species still differ strongly in their stoichiometry owing to inherent differences in the absorption and retention of different elements., To test the hypotheses, we analysed the C:N:P stoichiometry of 48 species of Artemisia and its close relatives from 65 sites across northern China., Elemental concentrations and stoichiometry had no correlation with latitude or longitude but showed clear altitudinal trends. Climate had a weak effect on plant elemental concentrations and stoichiometry but not on C concentration. Soil chemistry had significant effects on C and P concentrations, C:P and N:P. Nested models revealed that species identity accounted for more than 30% of the total variance of all elemental concentrations and stoichiometric ratios, and different species responded differently to environmental gradients., Synthesis. Our results highlight that even closely related species can vary importantly in plant elemental stoichiometry. This suggests that ecologists and global change researchers should be careful not to simply take a species' stoichiometry as representative of an entire taxonomic group for upscaling of plant chemical responses to climatic and edaphic variation in our fast changing world. [ABSTRACT FROM AUTHOR]

• Forest landscape change is closely related to geographical environment factors. • Integrating geographical environment factors analysis is imperative. • Using spatially explicit methods to analyze geographical environmental factors. • Integrated geo-environmental factors index well explain forest landscape change. Analysis of forest landscape changes and its driving factors is vital to forest ecosystem management and sustainable development. However, it is difficult to integrate various environment factors and explain the change of forest landscape. Research on the impact of integrate geographical environment factors on forest landscape changes is still lacking. In this study, we quantified forest area and mapped forest landscape distribution in 1990, 1995, 2000, 2005, 2000, 2010, and 2015 in Luoning County in the middle of the Yiluo River watershed by using multi-temporal land use data, and detected spatio-temporal changes of the forest landscape. Three types of forest landscape changes (unconverted, reforestation, and deforestation) and ten geographical environment factors (elevation, slope, proximity to previous forest edge, distance to rivers, mean annual temperature, mean annual precipitation, distance to roads, distance to residential centers, population density, Gross Domestic Product) were identified. Pearson correlation analysis and line regression analysis were applied to examine the relationships between forest landscape changes and geographical environment factors. Based on the relationships, correlation coefficient and adjusted R2 , these environment factors were formed into an integrated geographical environment factors index (IGEF), and an approach for analyzing forest landscape changes along the geographical environment factors gradient was proposed. The results showed that: (1) the total area of forest landscape decreased from 1990 to 2000 and continued to increase from 2000 to 2015; (2) reforestation and deforestation were closely related to individual geographical environment factors and IGEF index; (3) reforestation and deforestation mainly occurred in the areas with low and medium IGEF index values, while forest landscape unconverted was mainly distributed in the areas with high and medium IGEF index values. The observed forest landscape changes could be explained by a set of given geographical environmental factors. Our findings are expected to enhance the understanding of integrated analysis method of geographical environmental factors and contribute to the targeted forest landscape management in mountain areas. [ABSTRACT FROM AUTHOR]

The intensity of disturbance is an important factor influencing functional diversity of mountain meadow communities. The change pattern of functional diversity of mountain meadow communities along a tourism disturbance gradient in the Donglingshan Reserve was studied. Sixty plots of 2 m × 2 m of meadow communities were established, and species composition, traits and environmental variables were measured and recorded in each plot. Five functional diversity indices based on functional distances, such as FAD, MFAD, FDp, FDc and Rao indices, were used to calculate functional diversity. The results showed that functional diversity in meadow communities varied greatly. Functional diversity showed a linear decrease pattern with increase of disturbance intensity. Functional diversity was significantly correlated with disturbance intensity, elevation and slope. Functional diversity was quadratically increased with species richness and also correlated with species diversity and evenness. Environmental filtering was important to functional diversity pattern. The five indices were all effective in the analysis of functional diversity of mountain meadow communities. And functional diversity can be used as indicator of disturbance and degradation of mountain meadows. [ABSTRACT FROM AUTHOR]

Grassland plants contribute to carbon fixation through photosynthesis, which can in turn produce plant biomass. Previous studies have demonstrated that vegetation productivity is enhanced by improved soil nutrient status in humid environments and is influenced by climate in arid environments. However, the responses of biomass productivity to different patterns of climate-plant-soil in different natural grassland ecosystems have not been clearly and comprehensively analyzed. In this study, we systematically explore the functional patterns of different grasslands, as well as the underlying mechanisms in the response to key climatic, soil, and plant factors. The survey range covered broad environmental gradients from humid, semi-arid, to arid environments in Tibetan and Inner Mongolian Plateaus. We found that the above- and belowground biomass production gradually decreased from humid, semi-arid, to arid environments. Biomass production was sensitive to climatic factors in different environments. However, compared to soil and plant factors, climate was always the most important factor determining biomass production in all grassland types. Furthermore, biomass production was regulated mainly by climate and soil characteristics in humid environments, but by climate in arid environments. Specifically, the corresponding limiting factors of each factor largely dominated the effects of the corresponding factors on different grasslands. For instance, the climate dominated by temperature negatively influenced the soil nutrient availability and then influenced the aboveground biomass production in alpine humid grasslands. These findings enhance our understanding of the heterogeneity of mechanisms of different grasslands along broad environmental gradients, which are crucial for predicting the effects and consequences of environmental change on terrestrial ecosystem functioning. • Plant communities were surveyed along two broad environmental gradients. • Climatic factors had different effects on grasslands in different environments. • Climate was invariably the dominant factor on grasslands in different environments. • The auxiliary promoting effect of soil was enhanced in more humid environments. [ABSTRACT FROM AUTHOR]

The subtropical evergreen broad-leaved forests of Yunnan and Taiwan were compared along environmental and successional gradients with the aim of identifying important taxon and species diversity as well as the drivers of mountain biodiversity patterns. A detrended correspondence analysis of an exhaustive set of data collected from 105 and 223 plots for Yunnan and Taiwan, respectively, was applied to classify natural mature forest types. Additional data from 72 and 68 plots for Yunnan and Taiwan, respectively, were used for analyses of secondary succession. The floristic richness and diversity index were calculated for each type of forest. In Yunnan, the monsoon forests in mesic-humid sites had more taxa and tended to show higher species diversity than the other two forest types. In Taiwan, species diversity values were significantly higher in the Machilus- Castanopsis zone in the middle altitudes (500-1500 m) than for the other three forest zones. For both Yunnan and Taiwan, the forests at the middle successional stage showed significantly higher species diversity than those at the early successional stage. Differences in diversity between the middle and late stages were not significant. These findings highlight the high species diversity of the natural mature evergreen broad-leaved forests of both Yunnan and Taiwan. In the secondary forests, as succession proceeds, species diversity comes to resemble that of the natural mature forests. In both ecosystems, the drivers of species diversity patterns are moisture, altitude, and succession/disturbance. [ABSTRACT FROM AUTHOR]

As an important part of terrestrial ecosystem and the most sensitive to environmental changes, mountainous areas are rich in biodiversity and high value of ecosystem productivity. However, due to the unsustainable exploitation of natural resources, most of the world's mountain ecosystems are being subjected to soil erosion and biodiversity is rapidly being lost, so the establishment of mountain ecological reserves is of great importance. In view of this, this paper used the Qinling-Daba Mountain, Qinling Mountain and Daba Mountain of China as the research area. On the basis of various simulated ecosystem service from 2000 to 2015, the root mean square deviation analysis and ordered weighted averaged model were used to determine the spatial changes of ecosystem service on environmental gradients, the tradeoff between ecosystem services and the selection of optimal protection areas. Our results proved that ① net primary production, soil conservation and habitat quality were increase significantly with increasing altitude and vegetation cover fraction gradient, but were weaken water yield and grain production. ② The change in the trade-off between multiple pairs of ecosystem services in the Daba Mountain was stronger than in the Qinling-Daba Mountain and the Qinling Mountain, especially the trade-off relationship related to water yield. ③ Considering various scenarios and conservation efficiency, it was found that scenario 7 was the best solution. The net primary production, soil conservation, habitat quality, grain production, and water yield protection efficiency were 1.261, 4.845, 1.059, 1.333, and 1.390 respectively. Priority conservation areas were mainly distributed in mid-altitude, high-vegetation, and high-mean annual precipitation areas. In this study, the combination of ecosystem services and priority conservation areas can play an important role in the management of the Qinling-Daba Mountain, and provides a meaningful reference for the selection of nature reserves. • Mountain ecosystem services have large spatial heterogeneity on different environmental gradients. • The priority protection area was selected by comparing the protection efficiency of different areas. • Explore the mechanism analysis and the trade-off relationship between mountain ecosystem services. • The combination of ecosystem services and protected areas can provide reference for mountain ecological planning. [ABSTRACT FROM AUTHOR]