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Until now, the earliest fossil echinoderms have been predominantly known from the early Cambrian of Laurentia and West Gondwana. Here, we describe Sprinkleoglobus extenuatus gen. et sp. nov. from the Chengjiang biota (Cambrian Series 2, Stage 3) of Yunnan Province, China. The overall profile of the theca and the morphology of the ambulacra clearly establish it as an edrioasteroid echinoderm. This represents the first discovery of an unequivocal echinoderm from the early part of the Cambrian of South China and is among the oldest records of echinoderms globally. Our material shows that edrioasteroids were diverse and widely distributed from their first occurrence in the fossil record, suggesting an earlier origin for the group. We infer that Sprinkleoglobus and other early echinoderms were adapted for attaching to hard substrates, implying that the so‐called Cambrian substrate revolution was not a strong control on the early evolution of attachment in echinoderms. [ABSTRACT FROM AUTHOR]

Ecologists have generally concluded that species distributions are not random (e.g. aggregate), based on single‐species studies that applied single‐species–based statistical methods, like the negative binomial model. Although it is common knowledge that some specific species in an ecological community present aggregate distributions, this does not necessarily imply that the entire community presents an aggregate distribution. Studying community‐level distributional aggregation patterns requires different statistical methods.Herein, by utilizing a novel conspecific‐encounter index derived from a multiple species Markov transition model that accounts for the non‐independent sampling of consecutive individuals along line transects, we were able to show that tree assemblages in tropical forest ecosystems can present a strong signal of extensive distributional interspersion.This interesting result is not unexpected, given the fact that neighbouring tree individuals in highly diverse tropical forests are usually of different species, resulting in strong niche packing or interspersed patterns. In contrast, for the amphibian assemblages surveyed from southwestern China and central‐south Vietnam, the conspecific‐encounter index was found to be consistently high, implying that amphibian communities tend to be highly aggregate in space.Conclusively, using the conspecific‐encounter index derived from the Markov non‐independent sampling model, we provide a legible definition of community‐level distributional aggregation as an interspersed or cluster‐like distribution of different species. This definition is not idiosyncratic, as it is coincident with the definition of the contagion index used in landscape ecology. To this end, the model used in this paper establishes a framework explicitly linking community ecology and landscape ecology from a multi‐object perspective. [ABSTRACT FROM AUTHOR]

Beta diversity patterns along environmental gradients and underlying mechanisms constitute key research inquiries in biogeography. However, ecological processes often also influence the functional traits of biological communities, making the assessment of functional β‐diversity crucial. Ground beetles (Coleoptera: Carabidae) are one of the most species‐rich groups in the insect community, displaying strong habitat specificity and morphological differences. In this study, we explored the patterns of taxonomic and functional beta diversity in ground beetle communities along the altitudinal gradient of warm‐temperature forests. By partitioning beta diversity into turnover and nestedness components, we evaluated their relationship with spatial distance. Our findings indicate a decline in species and functional trait similarity with increasing elevation and geographic distance. Further analysis attributed both types of beta diversity in carabids to a combination of dispersal limitation and environmental filtering, with elevation and geographic distance emerging as significant factors. Interestingly, forest‐type variations were found to have no impact on the beta diversity of these communities. Our study reveals the impact of environmental filtering and dispersal limitation on both taxonomic and functional beta‐diversity, shedding light on carabid community assembly in localized warm‐temperature forest areas in eastern China. [ABSTRACT FROM AUTHOR]

Aim: Understanding the patterns and drivers of biodiversity across space and time is commonly based on species diversity, which may ignore species' functional role and evolutionary history and result in an incomplete understanding of community assembly. It is suggested that integrating species, functional, and phylogenetic diversity could provide a more holistic assessment of community assembly in natural ecosystems. This study aimed to explore the elevational patterns and environmental drivers of multiple facets of fish diversity and community structure in a subtropical river during the wet and dry seasons. Location: The Chishui River basin, China. Methods: We investigated the responses of fish species richness, functional richness, and phylogenetic diversity to elevation in different seasons. Moreover, we compared functional dispersion and mean pairwise distance with those obtained from null models to infer assembly mechanisms shaping community structure. Additionally, we examined the environmental drivers (e.g. water chemistry, temperature, and river size) of fish diversity and community structure. Results: Fish species richness, functional richness, and phylogenetic diversity showed a negative relationship with elevation in the Chishui River basin. Fish communities tended to be on average functionally random but phylogenetically clustered. Furthermore, phylogenetic structure exhibited a decreasing pattern along the elevational gradient. Despite no significant seasonal changes for fish diversity (except for phylogenetic diversity), fish communities became more phylogenetically overdispersed and clustered at low and high elevations in the dry season. Additionally, the responses of fish diversity and community structure to environmental variables were not synchronous. Conclusions: At the basin scale, environmental filtering was prevalent in shaping fish phylogenetic structure, whereas stochasticity was likely more important for functional structure. Moreover, the ecological mechanisms shaping individual fish communities switched from limiting similarity to environmental filtering as elevation increased, and the underlying forces at two ends of the elevational gradient became more prominent in the dry season. [ABSTRACT FROM AUTHOR]

Diversity-manipulation experiments suggest a positive effect of biodiversity on ecosystem properties (EPs), but variable relationships between species richness and EPs have been reported in natural communities. An explanation for this discrepancy is that observed richness-EPs relationships in natural communities change with environment and species functional identities. But how the relationships change along broad-scale climatic gradients has rarely been examined. In this paper, we sampled 848 plots of 20 × 30 m2 from boreal to tropical forests across China. We examined plot biomass with respect to environmental factors, tree species richness and functional group identity (FGI, i.e. evergreen vs deciduous, and coniferous vs broadleaf). Variation partitioning was used to evaluate the relative effects of the three classes of factors. We found that, most of the 'effects' (percentage of variation explained) of richness and FGI on forest biomass were shared with environmental factors, but species richness and FGI still revealed significant effects in addition to environment for plots across China. Richness and FGI explained biomass mainly through their shared effects instead of independent effects, suggesting that the positive biodiversity effect is closely associated with a sampling effect. The relative effects of richness, FGI and environment varied latitudinally: the independent effects of environment and richness decreased from boreal to subtropical forests, whereas the total effect of FGI increased. We also found that the slope of richness-biomass relationship decreased monotonically from boreal to subtropical forests, possibly because of decreasing complementarity and increasing competition with increasing productivity. Our results suggest that while species richness does have significant effects on forest biomass it is less important than environmental gradients and other biotic factors in shaping large-scale biomass patterns. We suggest that understanding how and why the diversity-EPs relationships change along climatic gradient would be helpful for a better understanding of real biodiversity effects in natural communities. [ABSTRACT FROM AUTHOR]

Most of the world's terrestrial biome types can be found in China. To systematically investigate species composition and structure of China's forest communities, we launched a long-term project consisting forest vegetation surveys across China's mountains in the mid 1990s. Over the study period, we have conducted vegetation surveys for 65 mountains and collected vegetation data from about 1500 forest plots, using consistent sampling protocols. In this paper we first introduce the aims, protocols, and major research themes of the project, and then describe the major characteristics of forest communities and their geographic patterns and climatic controls. As latitude increased, diameter at breast height (DBH) and height of trees increased, while individual density of trees and woody species richness decreased. Total basal area (TBA) of trees and species richness of herbs did not vary with latitude. Contemporary climate seems to drive these patterns: temperature was the leading factor for DBH, precipitation was most important for tree height and individual density, actual evapotranspiration (a surrogate of productivity) determined woody (trees and shrubs) species richness, and rainfall was the major controller of the herb species richness. The species-abundance relationship showed that species dominance (measured by the number of individuals per species) declined significantly from boreal forests to evergreen broadleaf forests from north to south. Our results are in line with the idea that productivity drives woody species richness. Similarly, we find that biomass (measured as TBA) is invariant along the environmental gradients. However, individual density varies dramatically, in contrast to the assumptions underlying the metabolic theory of ecology. [ABSTRACT FROM AUTHOR]

The relationship between species diversity and ecotope diversity has long been debated. But these debates seem meaningless because most of them were based on different definitions. In this paper, diversity has two components: richness based on the total number and evenness based on the relative abundance. Species diversity is distinguished into individual-counting diversity and biomass-based diversity. Ecotope diversity is divided into individual ecotope-counting diversity and ecotope-area based diversity. Under this definition, we make a comprehensive investigation into Dongzhi tableland of Loess Plateau by cooperating with local technicians. We find that individual-counting diversity is significantly correlated with biomass-based diversity in grassland ecosystems; individual ecotope-counting diversity and ecotope-area based diversity have a significant correlation. Therefore, it is unnecessary to divide species diversity into individual-counting diversity and biomass-based diversity in grassland ecosystems and to distinguish ecotope diversity into individual ecotope-counting and ecotope-area based diversity for the issues that have no special requirement for accuracy. But the analyses of the investigation data demonstrate that species diversity has no significant correlation with ecotope diversity. [ABSTRACT FROM AUTHOR]

Compared to other ecosystems, estuarine ecosystems have distinct carbon flux dynamics – the lateral carbon flux incurred by tidal activities, and methane generation under the anaerobic conditions of wetland soils. The conventional estimation of gross primary production (GPP) based on the light use efficiency (LUE) model used for non-wetland terrestrial ecosystems, therefore, cannot be applied directly to estuarine wetland ecosystems. In this paper, we estimated the 2005's annual carbon budget of an estuarine wetland on Chongming Island, Shanghai, and partitioned the losses of carbon due to lateral tidal dynamics and anaerobic methane production using an innovative technique. The average GPP calculated from eddy covariance between March and November was 261.79 μmol m−2 day−1, whereas that from the LUE model was 58.84 μmol m−2 day−1. The correlation coefficient between GPP simulated from the LUE model and that calculated from flux tower data was low in the growing season ( R2=0.55). We hypothesized that tidal activities and uncounted methane release were responsible for the difference, which can be predicted from measurements of remote sensing products such as land surface water index (LSWI), evapotranspiration (ET), and tide height (TH). We developed an integrated GPP model by combining the LUE model and an autoregression model to estimate carbon budget. The average GPP from the modified model increased to 263.38 μmol m−2 day−1, and R2 for the correlation between the simulated and calculated data increased to 0.88, demonstrating the potential of our technique for GPP estimation and quantification of seasonal variation in estuarine ecosystems. The approach developed in this study has great potential for correcting unavoidable errors when estimating carbon budget of coastal wetlands. Furthermore, global warming is expected to accelerate sea level rise, which may enhance the effect of tidal activities and increase the difficulty in estimating coastal carbon budgets using conventional methods. [ABSTRACT FROM AUTHOR]

Seed dynamics is an important part of stand dynamics in forest ecosystems. In this paper, 26 gaps were randomly selected to study the influence of gaps on the spatial and temporal patterns of seed rains in a tropical montane rainforest of Hainan Island, South China. Three zones for each gap, including outside gap zone (Non-gap), transitional gap zone (EG-CG), and central gap zone (CG), were designed, and four seed traps (each 1m × 1m in size) were placed in each zone. Seed rains were collected by these traps every 10 days from June 2001 to May 2002. Seed rain varied greatly with season and generally exhibited a pattern of unimodal change during the study period: seed abundance and species richness were both greater in the wet season than in the dry season. Gaps significantly influenced the temporal patterns of both species richness and density of seed rains. Gaps had no significant influences on the spatial distribution patterns of seed rain species richness, but significantly affected the spatial distribution pattern of seed rain densities. Among the three different zones of gaps, the outside gap zone generally received more seeds inputs than the two other gap zones. [ABSTRACT FROM AUTHOR]

Organic carbon storage in agricultural soils plays a key role in the terrestrial ecosystem carbon cycle. Paddy soils support important croplands in many parts of the world, especially in Asia. A thorough understanding of organic carbon storage in Chinese paddy soils would be helpful to both greenhouse gases emission and carbon sequestration studies. This paper examines soil organic carbon density (SOCD) and storage (SOCS) of paddy soils in China using the newly compiled 1:1,000,000 digital soil map of China as well as data from 1490 paddy soil profiles. Results show that paddy soils in China cover about 45.7 M ha, nearly 1.5 times more than the results of other studies. In China, the mean SOCD of paddy soils at a depth of 0-100 cm is 111.4 t C ha-1, with a SOCS of 5.1 Pg. These results are 66-75% higher than studies from other scientists. However, the mean SOCD of paddy soils from 0 to 20 cm is 37.6 t C ha-1, with a SOCS of 1.7 Pg, which is 89% higher than studies from other scientists. [ABSTRACT FROM AUTHOR]

The objective of this paper is to obtain a net primary production (NPP) regression model based on the geographically weighted regression (GWR) method, which includes spatial non-stationarity in the parameters estimated for forest ecosystems in China. We used data across China. We examine the relationships between NPP of Chinese forest ecosystems and environmental variables, specifically altitude, temperature, precipitation and time-integrated normalized difference vegetation index (TINDVI) based on the ordinary least squares (OLS) regression, the spatial lag model and GWR methods. The GWR method made significantly better predictions of NPP in simulations than did OLS, as indicated both by corrected Akaike Information Criterion (AICc) and R2. GWR provided a value of 4891 for AICc and 0.66 for R2, compared with 5036 and 0.58, respectively, by OLS. GWR has the potential to reveal local patterns in the spatial distribution of a parameter, which would be ignored by the OLS approach. Furthermore, OLS may provide a false general relationship between spatially non-stationary variables. Spatial autocorrelation violates a basic assumption of the OLS method. The spatial lag model with the consideration of spatial autocorrelation had improved performance in the NPP simulation as compared with OLS (5001 for AICc and 0.60 for R2), but it was still not as good as that via the GWR method. Moreover, statistically significant positive spatial autocorrelation remained in the NPP residuals with the spatial lag model at small spatial scales, while no positive spatial autocorrelation across spatial scales can be found in the GWR residuals. We conclude that the regression analysis for Chinese forest NPP with respect to environmental factors and based alternatively on OLS, the spatial lag model, and GWR methods indicated that there was a significant improvement in model performance of GWR over OLS and the spatial lag model. [ABSTRACT FROM AUTHOR]

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Microorganisms are essential in soil biogeochemical processes and vegetation establishment. Nonetheless, investigating predictable patterns in the microbial structure during forest restoration damaged by natural or human factors in southwestern China is still limited. Hence, the study intended to explore the effects of forest restoration damaged by illegal construction, abandoned mines, and meteorological disasters on the microbial structure and its consequence on ecosystem functioning. The results uncovered that soil and plant attributes in the restoration forests damaged by illegal construction were similar to the natural community. Furthermore, the alpha diversity indexes were higher in the restoration forests damaged by human factors than in the natural community. Co‐occurrence network analysis identified hub bacterial (e.g., Roseiarcus and Comamonas) and fungal (e.g., Exophiala and Botryotrichum) taxa, proving densely connected interactions with other microorganisms. Restoration forests damaged by illegal construction harbored beneficial genera belonging to Proteobacteria (Nordella, Xanthobacteraceae, and Sphingomonas) and Basidiomycota (Panaeolus, Psilocybe, and Sebacina), whereas restoration forests damaged by abandoned mines presented specialized bacteria involved in dark sulfur oxidation and ureolysis. Correlation analysis showed that soil properties, especially water content and pH, were the dominant factors affecting the microbial communities. Tree and shrub alpha diversities were significantly related to Chloroflexi in the natural community, and herbaceous richness was remarkably related to Proteobacteria and Mortierellomycota in the restoration forest damaged by human factors. Collectively, this comprehensive analysis generates novel insights to explore the contrasting responses of microbial communities during the process of restoration and provides essential microbial indicators for habitat restoration in southwestern China. [ABSTRACT FROM AUTHOR]

Cnidarians are phylogenetically located near the base of the ‘tree of animals’, and their early evolution had a profound impact on the rise of bilaterians. However, the early diversity and phylogeny of this ‘lowly’ metazoan clade has hitherto been enigmatic. Fortunately, cnidarian fossils from the early Cambrian could provide key insights into their evolutionary history. Here, based on a scrutiny of the purported hyolith Burithes yunnanensis Hou et al. from the early Cambrian Chengjiang biota in South China, we reveal that this species shows characters distinct from those typical of hyoliths, not least a funnel-shaped gastrovascular system with a single opening, a whorl of tentacles surrounding the mouth, and the lack of an operculum. These characters suggest a great deviation from the original definition of the genus Burithes, and a closer affinity with cnidarians. We therefore reassign the material to a new genus: Palaeoconotuba. Bayesian inference of phylogeny based on new anatomical traits identifies a new clade, including Palaeoconotuba and Cambrorhytium, as a stem group of sessile medusozoan cnidarians that are united by the synapomorphies of developing an organic conical theca and a funnel-like gastrovascular system. This study unveils a stem lineage of medusozoans that evolved a lifelong conical theca in the early Cambrian. [ABSTRACT FROM AUTHOR]

Nitrogen (N) and phosphorus (P) are crucial nutrients for regulating plant growth. The classic growth rate hypothesis (GRH) proposes that fast‐growing organisms have lower N:P ratios, and it is promising to predict net primary productivity (NPP) using the leaf N:P ratio at the community level (N:PCom). However, whether leaf N:P ratio can predict NPP in natural ecosystems on a large scale remains nebulous. Here, we systematically calculated leaf N:PCom (community biomass‐weighted mean and species arithmetic mean) using the consistently measured data of 2192 plant species‐site combinations and productivity (biomass‐based aboveground NPP and flux‐based NPP) in 66 natural ecosystems in China. Unexpectedly, leaf N:PCom hardly predicted productivity in natural ecosystems due to their weak correlation, although significantly negative or positive relationships across different ecosystems were observed. The ambiguous relationship between leaf N:P and species dominance reflected a luxury consumption of N and P in turnover and structure in natural communities, unlike what GRH suggests. Climate, soil, and leaf nutrients (rather than N:P) influenced productivity, which highlighted the importance of external environment and nutrient constrains. Our findings pose a major challenge for leaf N:PCom as a direct parameter in productivity models and further question the direct application of classic hypotheses in short‐term experiments or model species to long‐term and complex natural ecosystems. [ABSTRACT FROM AUTHOR]

A number of well‐preserved fossil taxa from the early Cambrian Chengjiang biota of South China have played important roles in the construction and analysis of the early evolutionary tree of metazoans. Certain other Chengjiang taxa, erected based on limited characters, have yielded little or no information concerning key aspects of their palaeobiology, and consequently their phylogenetic significance has been difficult to assess. One such taxon is the large conical animal Glossolites magnus. Exceptionally preserved new material of this soft‐bodied species herein, bearing oral tentacles and internal structures, indicates that G. magnus is not, as previously proposed, a hyolith. This work provides further information about possible biological affinities and palaeoautecology, which still remain open questions. [ABSTRACT FROM AUTHOR]

The Middle‒Late Mesozoic massive volcanism formed a considerable thickness of volcanic‐sedimentary strata in western Liaoning, northern China. Concomitantly, it elevated phosphorus (P) availability for the rapid bloom of the terrestrial Yanliao and Jehol biotas, which developed highly abundant biodiversity and biomass. Hence, systematic tectonic and geochemical analyses of these volcanic‐sedimentary sequences with a significant P fluctuation would advance our understanding of the coevolutionary relationship between terrestrial biotas and regional tectonics. Here, we show that the secular variation of P availability in the Mesozoic volcanic rocks were the immediate results of the changes in volcanic intensity and lithospheric thickness controlled by the geological background of the cratonic destruction resulting from the paleo‐Pacific plate subduction. This study reveals the constraint effect of regional tectonics on the evolution of terrestrial ecosystems through the volcanism and P cycle. Plain Language Summary: The phosphorus (P) is necessary for biotas and mainly comes from volcanics in areas dominated by volcanism closely related to deep‐Earth processes. Thus, the origin of P changes in volcanics can provide key evidence for the intrinsic relations between deep processes and biota evolution. Here, we present tectonic and geochemical analyses for the Mesozoic fossil‐bearing volcanic‐sedimentary strata in northern China. The westward subduction of the paleo‐Pacific plate triggered the crustal thickening and subsequent lithospheric thinning of the East Asia continent. These dynamic processes controlled the volcanic intensity and P variation, resulting in remarkable changes in P availability that led to the rise and fall of terrestrial biotas. Hence, P variations in volcanic sequences reveal the linkage between regional tectonics and biota evolution. This study represents an effort to explore how tectonic processes constrained terrestrial biotas involving multidisciplinary methods. Key Points: The paleo‐Pacific subduction triggered the cratonic destruction and thus controlled the intensity of volcanism in the Middle‒Late MesozoicThe change of lithospheric thickness triggered by the paleo‐Pacific subduction caused the variation of P content in the volcanicsRegional tectonics could impact the evolution of terrestrial ecosystems through the volcanism and nutrient P cycle [ABSTRACT FROM AUTHOR]

Situated at the easternmost area of the Late Mesozoic Jehol Biota, China, abundant fossils, including invertebrates, vertebrates and plants, were collected from the Early Cretaceous Yingzuilazi Formation of the Baishan Basin, southeastern Jilin. The faunal remains from this formation distinctly belong to the Early Cretaceous Lycoptera-Ephemeropsis-Eosestheria assemblage of the Jehol Biota. Based on the gross leaf morphology and epidermal structures, two new species and one indeterminate species of genus Solenites (Czekanowskiales), S. baishanensis sp. nov., S. gracilis sp. nov. and S. sp. are described in this paper. This is the first fossil plant of Czekanowskiales reported from this new fossil locality of the easternmost area of the Late Mesozoic Jehol Biota, China. The new discovery contributes to improve our knowledge for understanding of leaf morphology, epidermal characters and diversity of this genus during the Early Cretaceous time, and extends geologic and geographic distribution of Solenites in northern China and Eurasia. Along with consideration of associated plant and faunal assemblages and sedimentology, we suggest that the regional climate was warm and moderately humid with seasonal temperature and precipitation variations in warm-temperate zone during the Early Cretaceous. [ABSTRACT FROM AUTHOR]

The Early Cretaceous Jehol Biota evolution has remarkable spatiotemporal correlation with the destruction of the North China craton though the coupling mechanism remains enigmatic. The craton destruction was accompanied by intense magmatic activity and the released volatiles and nutrients might have had climatic and environmental impacts on the biotic evolution. In this study, we investigated the mentioned hypothetical causal link by determining concentrations and total emissions of volatile elements (S, F, Cl) and bulk‐rock P contents of volcanic rocks that were erupted during the pre‐flourishing, flourishing and post‐flourishing stages of the Jehol Biota. Our results show that the volcanism near the flourishing stage has lower S (1,083–2,370 ppm), Cl (1,277–5,608 ppm) and higher P2O5 contents (0.48–0.84 wt.%) than that in the non‐flourishing stages with S of 1,991–3,288 ppm, Cl of 7,915–12,315 ppm and P2O5 of 0.17–0.23 wt.%. Fluorine contents in the three stages vary from 893 to 3,746 ppm. The total volatile emissions are minor in the flourishing stage (1–14 Gt S, 0.6–10 Gt Cl, 0.6–9 Gt F) but elevated in the non‐flourishing stages (2–766 Gt S, 4–1,168 Gt Cl, 1–175 Gt F). Our data suggest that regional climatic and environmental impacts of volcanism in the non‐flourishing stages probably hindered the species diversification. The high P flux released from lithospheric mantle‐derived lavas during the peak time of craton destruction might have enhanced primary productivity and contributed to the flourishing of the Jehol Biota. Our study provides insights into the relationship between the biosphere and deep geodynamic processes driven by volcanism. Plain Language Summary: It is generally believed that volatiles, such as S, Cl, and F, released by massive volcanic events may have strong ecological pressures both at the local and global scales. However, it is puzzling that the flourishing of the Jehol Biota, an Early Cretaceous terrestrial lagerstätte recording the origin and early evolution of feathered dinosaurs, birds, mammals, and angiosperms, occurred simultaneously with extensive volcanic activities in the northeastern China. To find the possible influence of volcanism on the biotic evolution, we determined the contents and total emissions of S, Cl, and F (toxic gases) and bulk‐rock P (nutrient) contents of volcanic rocks that were erupted during the pre‐flourishing, flourishing, and post‐flourishing stages of the Jehol Biota. Our results show that the volcanism at the flourishing period of the Jehol Biota was dominated by intermediate‐mafic magmas, with the total S, Cl, and F emissions having limited impacts on the local climate and environment, while the high P flux released from lavas might have enhanced primary productivity. On the contrary, the intermediate‐felsic volcanic rocks in the non‐flourishing stage released abundant toxic gases and the P flux was limited, which probably hindered the species diversification. Key Points: Volcanic gases (S, Cl, and F) had limited climatic effects in the flourishing stage of the Jehol BiotaHigh P flux from lithospheric mantle‐derived lavas facilitated the flourishing of the Jehol BiotaVolcanism associated with the North China craton destruction affected terrestrial biota evolution [ABSTRACT FROM AUTHOR]

Accurately understanding the characteristics of a wetland ecological restoration plant communities and their species diversity relationships is the key to improving wetland management and biodiversity protection. To see the effects of restoration strategies implemented in Xinqiang River National Wetland Park, China, we studied 4 models for ecological restoration, namely protection and conservation (PC), reasonable utilization (RU), restoration and reconstruction (RR) and the building of constructed wetland (CW). We then analyzed the features of the plant communities, species diversity and soil properties, and carried out a correlation analysis between plant communities and the species diversity. Finally, we selected four key communities and analyzed their features and soil properties using a symmetric matrix. Results showed that the soil in the PC model had the highest amount of available phosphorus, available nitrogen and pH value. The soil had higher moisture content in the RU model and CW model than the other 2 models. Based on the correlation analysis, we found that there are obvious common characteristics among different ecological restoration types, that is, the diversity characteristics of tree layer, shrub layer and herb layer have obvious differentiation characteristics. We identified four features of the community characteristics that could improve species diversity: SA, TH, HH and SCD. The results of this study have provided a theoretical basis that there is a coupling relationship between ecological community characteristics and species diversity. The above coupling results have practical significance for maintaining good ecological structure and diversity protection. [ABSTRACT FROM AUTHOR]

Aim: Both ecological and evolutionary processes shape biological communities along elevational gradients. Compared to above‐ground taxa, elevational patterns and processes of below‐ground animals are little studied. Here, we investigated how environmental gradients across elevation may affect species divergence in the past and act as filters of contemporary assembly of soil detritivores via traits. We asked: (1) Are environmental filtering processes due to elevation, vegetation or microhabitat‐related factors driving isotomid springtail community assembly across elevation; (2) did species divergences occur after mountain uplift; and (3) are there environmental factors related to species divergences in the past. Location: Changbai Mountain, north‐east China. Taxon Isotomidae, Collembola. Methods: We collected isotomid springtails from 800 to 2150 m above sea level and reconstructed the phylogeny using mitochondrial genome sequencing. We inspected the body length, number of ommatidia and pigmentation, and determined their evolutionary patterns. We then derived community parameters using trait‐based and metacommunity phylogenetic approaches and used linear mixed‐effects models to identify environmental variables that allow predicting community trait and phylogenetic parameters. Results: Isotomid springtails differed more in traits when co‐occurring in environments with lower soil nitrogen, typically at higher elevations. Most communities exhibited phylogenetic clustering, but this pattern was not related to elevation or any environmental variables. These isotomid species mainly diverged in the Mesozoic with some divergence events associated with soil N and pH, as well as other factors covarying with the contemporary elevational gradient studied. The current communities comprised old phylogenetic lineages possessing traits that have undergone evolutionary drift. Main conclusions: While environmental gradients act as filters for below‐ground detritivores, evolution of traits preconditions their assembly. Species divergence likely resulted from filtering processes of past environments resembling the present day. Below‐ground diversity in Changbai Mountain is mainly based on the persistence of old phylogenetic lineages, while recent speciation is of little importance. [ABSTRACT FROM AUTHOR]

The deep‐sea hexactinellid sponge Euplectella is an iconic living genus with no known fossil record. The family Euplectellidae (which includes a subset of genera that share the common name 'Venus' flower basket') has a very sparse record from the Middle Cretaceous onwards, and an estimated crown‐group origin at around 300 Ma based on molecular clocks. New material of Venus' flower baskets from the latest Ordovician Anji Biota of China (444 Ma) dramatically extends the known and predicted range of the group, with implications for the diversification of the class Hexactinellida and the timing of development of deep‐sea ecosystems. The new material is described as Anjiplectella davidipharus gen. et sp. nov., with an additional taxon remaining in open nomenclature but demonstrating diversification within the group by this time. [ABSTRACT FROM AUTHOR]

Peatlands, an important carbon pool in terrestrial ecosystems, are often characterised by a hummock–hollow microtopography, which has important implications for hydrologic conditions, biotic community structure and carbon cycling. However, dynamics of microtopography formation are poorly understood. Moss‐inhabiting diatoms are sensitive to water table change and may be used to infer microtopography formation. Sixty‐three surface moss samples were collected from four Sphagnum peatlands in the Changbai Mountains (north‐eastern China), covering a water table gradient of 0–55 cm. Ordination analyses revealed that depth to the water table (DWT) was the determinant of diatom distribution, and its sole effect explained 15% of total variance in diatom composition. Accordingly, a diatom‐based water table transfer function was developed using a weighted averaging model with inverse deshrinking (R2 = 0.82, RMSEP = 5.63 cm with leave‐one‐out cross validation), and applied to diatom records of a Sphagnum hummock profile. Quantitative reconstruction of DWT showed that the height of the Sphagnum hummock increased obviously in the early stage and then remained relatively stable when the reconstructed height was more than 35 cm. The results suggested that annual addition of Sphagnum litter exceeded its decomposition during the early stage of hummock formation, and Sphagnum production and decomposition reached equilibrium when the hummock had grown to a certain height. This is the first study to explore dynamics of hummock height using moss‐inhabiting diatoms, and hence provides a novel tool for quantitative reconstruction of microtopography formation in Sphagnum peatlands. [ABSTRACT FROM AUTHOR]

While the morphology and evolution of the quadrate among early birds and through the evolutionary origin of birds is not well known, we add to knowledge about that past diversity through description of the morphology of the quadrate in the unusually elongate skull of the Cretaceous enantiornithine bird Longipteryx chaoyangensis. The lateral and caudal surfaces of the quadrate are well exposed in two specimens revealing morphologies typical of early birds and their dinosaurian close relatives like a small otic head and two mandibular condyles. However, both skeletons exhibit quadrates with a unique, enlarged lateral crest that has not been previously described among Mesozoic birds. It is possible that the rostral surface of this lateral expansion served as the origination site for enlarged jaw musculature in a manner similar to the enlarged subcapitular tubercle in extant galloanserine birds. The caudally concave surface of the quadrate likely reflects some aspect of cranial pneumaticity, with its shape and position reminiscent of quadrates found in close non‐avialan maniraptoran relatives. It is possible that this lateral crest has a wider distribution among enantiornithines and other early birds and that the crest has been misidentified as the orbital process in some more damaged specimens. In addition, the enlarged lateral mandibular condyle (relative to the medial condyle) differs from the condition typically reported among enantiornithines and could indicate a difference in jaw function or mechanics in this bird with an elongated rostrum, or simply misinterpretations of morphology. Further examination of the quadrate in temporally early and phylogenetically stemward birds, along with their close outgroups, could greatly impact the study of several different aspects of bird biology including assessment of phylogenetic relationships, interpretation of the function and kinematics of the skull, reconstruction of foraging paleoecology, and evolution of skull morphological diversity among Mesozoic birds. [ABSTRACT FROM AUTHOR]

Summary: Climate and plant invasion can shape biotic communities at large spatial scales. Yet, how diverse groups of organisms associated with an invasive plant change simultaneously with latitude and the roles of climate and plant invasion remains unclear.We conducted a field survey of plants (native vs exotic), soil fungi (pathogenic, saprotrophic, arbuscular mycorrhiza fungi (AMF) and ectomycorrhizal (EcM) fungi) and arthropods (herbivores, predators and detritivores) associated with the invasive plant Alternanthera philoxeroides at 49 sites spanning 14 latitudinal degrees in China.Results showed that diversity and composition of these functional groups changed differently with latitude, partially due to their specific responses to climate, invasion of A. philoxeroides and other biotic environments. Moreover, A. philoxeroides invasion and/or composition of other plants, rather than climate, predicted the diversity and richness of major functional groups and partly explained variance in composition of putative fungal pathogens.Our results suggest that climate and plant invasion could affect the diversity and composition of diverse groups of organisms simultaneously and their relative importance might vary among functional groups. Thus, it is necessary to explore latitudinal patterns and underlying drivers of diverse groups of organisms simultaneously to improve our ability to predict and mitigate threats posed by plant invasion and climate change. [ABSTRACT FROM AUTHOR]

As the number of non‐native invasive species in the world is increasing, there is a pressing need to understand the effects of invasive species on recipient biotic communities to improve our ability to migrate or relieve their potential negative effects on biodiversity and ecosystem functions. Plant invasions have been shown to impose great threats to aboveground biotic communities; however, invasive impacts on soil biota remain ambiguous, partially because of the paucity of studies with a large number of species across biogeographic gradients. Here, we characterized rhizosphere fungal communities of 53 native and invasive plants spanning approximately 1800 km in China, as well as eight pairs of phylogenetically related native versus invasive plants in a greenhouse experiment. The results of both field survey and greenhouse experiment showed that rhizosphere fungal composition was primarily predicted by plant phylogeny (e.g. family and species), and plant geographic origin (native vs. invasive) and abiotic factors had much smaller effects. We detected no differences in the number and relative abundance of total and family/species‐specific OTUs (i.e. overall, pathogens and mutualists) associated with these native and invasive plants on average, suggesting novel co‐evolution between native soil fungi and these invasive plants. These results suggest that non‐native plant invasions had only a weak impact on soil fungi, partially due to stronger controls of plant evolution on rhizosphere fungi and adaptation of native fungi to these invasive species. Interestingly, rhizosphere fungal composition was more variable between invasive plants than between native plants at middle latitudes, potentially creating spatial variations in plant–soil interactions and, in turn, invasion dynamics. These novel findings highlight the importance of integrating phylogenetic and biogeographical approaches to explore invasive effects on native biota. [ABSTRACT FROM AUTHOR]

Soil methanogenic microorganisms are one of the primary methane‐producing microbes in wetlands. However, we still poorly understand the community characteristic and metabolic patterns of these microorganisms according to vegetation type and seasonal changes. Therefore, to better elucidate the effects of the vegetation type and seasonal factors on the methanogenic community structure and metabolic patterns, we detected the characteristics of the soil methanogenic mcrA gene from three types of natural wetlands in different seasons in the Xiaoxing'an Mountain region, China. The results indicated that the distribution of Methanobacteriaceae (hydrogenotrophic methanogens) was higher in winter, while Methanosarcinaceae and Methanosaetaceae accounted for a higher proportion in summer. Hydrogenotrophic methanogenesis was the dominant trophic pattern in each wetland. The results of principal coordinate analysis and cluster analysis showed that the vegetation type considerably influenced the methanogenic community composition. The methanogenic community structure in the Betula platyphylla–Larix gmelinii wetland was relatively different from the structure of the other two wetland types. Indicator species analysis further demonstrated that the corresponding species of indicator operational taxonomic units from the Alnus sibirica wetland and the Betula ovalifolia wetland were similar. Network analysis showed that cooperative and competitive relationships exist both within and between the same or different trophic methanogens. The core methanogens with higher abundance in each wetland were conducive to the adaptation to environmental disturbances. This information is crucial for the assessment of metabolic patterns of soil methanogenic archaea and future fluxes in the wetlands of the Xiaoxing'an Mountain region given their vulnerability. [ABSTRACT FROM AUTHOR]

Investigates nutrient compartmentation and ecosystem development on naturally-colonized clay wastes in China. Redistribution of soil nutrients to the developing vegetation; Importance of nutrient cycling; Successional development of ecosystems on wastes; Implications for reclamation schemes.

Despite several decades of study in community ecology, the relative importance of the ecological processes that determine species co‐occurrence across spatial scales remains uncertain. Some of this uncertainty may be reduced by studying the scale dependency of community assembly in the light of environmental variation. Phylogenetic information and functional trait information are often used to provide potentially valuable insights into the drivers of community assembly. Here, we combined phylogenetic and trait‐based tests to gain insights into community processes at four spatial scales in a large stem‐mapped subtropical forest dynamics plot in central China. We found that all of the six leaf economic traits measured in this study had weak, but significant, phylogenetic signal. Nonrandom phylogenetic and trait‐based patterns associated with topographic variables indicate that deterministic processes tend to dominate community assembly in this plot. Specifically, we found that, on average, co‐occurring species were more phylogenetically and functionally similar than expected throughout the plot at most spatial scales and assemblages of less similar than expected species could only be found on finer spatial scales. In sum, our results suggest that the trait‐based effects on community assembly change with spatial scale in a predictable manner and the association of these patterns with topographic variables, indicates the importance of deterministic processes in community assembly relatively to random processes. [ABSTRACT FROM AUTHOR]

A major challenge in community ecology is to understand the underlying factors driving metacommunity (i.e., a set of local communities connected through species dispersal) dynamics. However, little is known about the effects of varying spatial scale on the relative importance of environmental and spatial (i.e., dispersal related) factors in shaping metacommunities and on the relevance of different dispersal pathways. Using a hierarchy of insect metacommunities at three spatial scales (a small, within‐stream scale, intermediate, among‐stream scale, and large, among‐sub‐basin scale), we assessed whether the relative importance of environmental and spatial factors shaping metacommunity structure varies predictably across spatial scales, and tested how the importance of different dispersal routes vary across spatial scales. We also studied if different dispersal ability groups differ in the balance between environmental and spatial control. Variation partitioning showed that environmental factors relative to spatial factors were more important for community composition at the within‐stream scale. In contrast, spatial factors (i.e., eigenvectors from Moran's eigenvector maps) relative to environmental factors were more important at the among‐sub‐basin scale. These results indicate that environmental filtering is likely to be more important at the smallest scale with highest connectivity, while dispersal limitation seems to be more important at the largest scale with lowest connectivity. Community variation at the among‐stream and among‐sub‐basin scales were strongly explained by geographical and topographical distances, indicating that overland pathways might be the main dispersal route at the larger scales among more isolated sites. The relative effect of environmental and spatial factors on insect communities varied between low and high dispersal ability groups; this variation was inconsistent among three hierarchical scales. In sum, our study indicates that spatial scale, connectivity, and dispersal ability jointly shape stream metacommunities. [ABSTRACT FROM AUTHOR]

The Guanshan Biota of the Wulongqing Formation (Cambrian Series 2, Stage 4) is a typical Burgess Shale‐type Lagerstätte, containing not only a diverse assemblage of exceptionally preserved body fossils but also abundant, sophisticated trace fossils. Detailed ichnological study of the lower part of the Wulongqing Formation from the Longbaoshan and Xinglongcun sections in the Kunming area, Yunnan, South China, reveals the presence of 17 ichnospecies, including Aggregatella isp., Cruziana isp., Didymaulichnus lyelli, Diplichnites isp., Guanshanichnus glockerichnoides, Monomorphichnus isp., Palaeophycus isp., Planolites beverleyensis, Planolites montanus, Planolites isp., Psammichnites isp., Phycodes isp., Skolithos verticalis, Thalassinoides isp., Treptichnus pedum, and two types of non‐specific coprolites. These trace fossils represent burrowing or locomotion behaviours of arthropods and vermes, and belong to the Cruziana and Skolithos ichnofacies. As the outcrop at the Xinglongcun section is not well exposed, a systematic sedimentary study was conducted at the Longbaoshan section. The Guanshan ichnofauna in the lower Wulongqing Formation at the Longbaoshan section occur in fine‐grained siliciclastic rocks with wavy bedding, lenticular bedding, and wrinkle structures, reflecting a tidal flat environment. The abundance of diverse trace fossils in the tidal flat facies indicate that many taxa, mostly arthropods, were able to colonize the very shallow marine environments, supporting the landward expansion of the Early Cambrian ecosystems. [ABSTRACT FROM AUTHOR]

The avian digestive system, like other aspects of avian biology, is highly modified relative to other reptiles. Together these modifications have imparted the great success of Neornithes, the most diverse clade of amniotes alive today. It is important to understand when and how aspects of the modern avian digestive system evolved among neornithine ancestors in order to elucidate the evolutionary success of this important clade and to understand the biology of stem birds and their closest dinosaurian relatives: Mesozoic Paraves. Although direct preservation of the soft tissue of the digestive system has not yet been reported, ingested remains and their anatomical location preserved in articulated fossils hint at the structure of the digestive system and its abilities. Almost all data concerning direct evidence of diet in Paraves comes from either the Upper Jurassic Yanliao Biota or the Lower Cretaceous Jehol Biota, both of which are known from deposits in north‐eastern China. Here, the sum of the data gleaned from the thousands of exceptionally well‐preserved fossils of paravians is interpreted with regards to the structure and evolution of the highly modified avian digestive system and feeding apparatus. This information suggests intrinsic differences between closely related stem lineages implying either strong homoplasy or that diet in each lineage of non‐ornithuromorph birds was highly specialized. Regardless, modern digestive capabilities appear to be limited to the Ornithuromorpha, although the complete set of derived feeding related characters is restricted to the Neornithes. [ABSTRACT FROM AUTHOR]

Aim: The Hengduan Mountains (HDM) of southwest China is a biodiversity hotspot and harbours one of the world's richest temperate floras. However, the origin and evolution of its biota remain largely unresolved. Here we explore the impact of mountain uplift on the diversification process of biodiversity in this hotspot using alpine bamboos. Location: The HDM region, southwest China. Taxon: Alpine bamboos. Methods: We used ddRAD‐seq data from the most complete sampling of alpine bamboos undertaken to date (79% of the species diversity), to investigate their evolutionary history. The ancestral area of these bamboos was reconstructed using a time‐calibrated phylogeny in BioGeoBEARS and diversification rates were inferred using BAMM analyses. In addition, the impact of mountain uplift on the divergence of alpine bamboos was evaluated using trait‐dependent models of diversification. Results: The alpine bamboos were strongly supported as monophyletic, and the relationships within them were robustly resolved. Fargesia was found to be polyphyletic and Yushania was resolved as monophyletic. Alpine bamboos originated outside the HDM region during the late Miocene, and spread to this region in the Pliocene, undergoing a significant acceleration in net diversification, which is temporally congruent with the orogeny. The speciation rate increased with altitude and a high diversification rate, estimated to be 0.75 species per million years, was detected for alpine bamboos distributed in high elevations. Main Conclusions: Our study demonstrates that heterogeneous mountain habitats and geographical isolation of alpine bamboos, which have limited dispersal ability, are important drivers for their rapid diversification. This study also highlights the power of complementary analyses in revealing the link between species diversification and past geological changes. [ABSTRACT FROM AUTHOR]

The article focuses on a joint symposium of British Ecological Society and the Ecological Society of China on environmental problems of industrialized countries, which was held at Beijing, China, in September 1988. Industrial development is the main cause of the environmental pollution in both China and the Great Britain. Topics included in the symposium are, air and water pollution, its management, land restoration, rural and urban ecosystems and nature conservation. Environmental awareness among the people of the country lead to the formation of pollution control schemes.

Understanding how grazing activity drives plant community structure or the distribution of specific species in a community remains a major challenge in community ecology. The patchiness or spatial aggregation of specific species can be quantified by analyzing their relative coordinates in the community. Using variance and geostatistical analysis methods, we examined the quantitative characteristics and spatial distribution of Stipa breviflora in a desert steppe in northern China under four different grazing intensities (no grazing, NG, light grazing, LG, moderate grazing, MG, and heavy grazing, HG) at three small spatial scales (10 × 10 cm, 20 × 20 cm, 25 × 25 cm). We found that grazing significantly increased cover, density, and proportion in standing crop of S. breviflora, but decreased height. The spatial distribution of S. breviflora was strongly dependent upon the sampling unit and grazing intensity. The patchiness of S. breviflora reduced with sampling scale, and spatial distribution of S. breviflora was mainly determined by structural factors. The intact clusters of S. breviflora were more fragmented with increasing grazing intensity and offspring clusters spread out from the center of the parent plant. These findings suggest that spatial aggregation can enhance the ability of S. breviflora to tolerate grazing and that smaller isolated clusters are beneficial to the survival of this dominant species under heavy grazing. [ABSTRACT FROM AUTHOR]

Exploring the community assembly has been important for explaining the maintenance mechanisms of biodiversity and species coexistence, in that it is a central issue in community ecology. Here, we examined patterns of the community phylogenetic structure of the subalpine meadow plant community along the slope gradient in the Qinghai–Tibetan Plateau of China. We surveyed all species and constructed the phylogenetic tree of the plant community based on data from the Angiosperm Phylogeny Group III. We selected the net relative index (NRI) and evaluated the community phylogenetic structure along the five slope plants communities. We found that the phylogenetic structure varied from phylogenetic clustering to phylogenetic overdispersion with the slope aspect from north to south. In the north slope, the community phylogenetically cluster indicated that the limiting similarity played a leading role in the community assembly and the maintenance of biodiversity. Community phylogenetic overdispersion in the east, southeast, and south slopes indicated that habitat filtration was the driving force for community assembly. The NRI index of the northeast slope was close to zero, implying random dispersion. But it may be driven by the neutral process or limiting similarity, in that the community assembly process was the result of a combination of several ecological factors and thus required further study. [ABSTRACT FROM AUTHOR]

In recent years, the importance of microbial diversity and function to ecosystem restoration has been recognized. The aim of this work was to investigate the diversity and composition of bacterial communities in response to reclamation of a soil subsidence area affected by mining activities. Soil samples were taken in two seasons (December 2012 and July 2013) from a mining reclamation region at the Liuxin national reclamation demonstration area in China and an adjacent coal-excavated subsidence region. 454 high-throughput sequencing technology was used to compare the composition and diversity of bacterial communities in reclaimed soil to that in subsided soil. Predominant phyla in soils were Proteobacteria, Actinobacteria, Acidobacteria, and Planctomycetes, with Proteobacteria making up the majority of the community. Long-term reclamation was found to have significant influences on bacterial communities, and the bacterial community diversity and composition varied between reclaimed and subsided soil. Seasonal fluctuations also contributed to variation in soil bacterial diversity and community composition, but were minor in comparison to effects of reclamation. Differences observed in bacterial community structure and diversity were related to both fertilizer treatment and vegetation, likely through the effects of soil attributes. Soil organic matter and total nitrogen and available potassium were important factors shaping the microbial communities. The reclaimed soil had higher community diversity of bacteria than subsided soil, which suggests that long-term applications of organic amendments and vegetation mixed sowing had significant impacts on soil remediation and microbial diversity. [ABSTRACT FROM AUTHOR]

The processes that structure assemblages of species in hyper-diverse genera, such as Ficus (Moraceae), are not well understood. Functional diversity of co-occurring species can reveal evidence for assembly processes; however, intraspecific variation may weaken species-level patterns. We studied whether functional and phylogenetic diversity of Ficus species indicated the effects of spatial variation in filters associated with topography or niche partitioning related to resource use and biotic interactions. We also asked whether individual trait patterns supported species-level patterns. We studied six traits (leaf area, succulence, specific leaf area [SLA], maximum diameter breast high [dbh], fruit size, and latex exudation) for 22 Ficus species and 335 individuals ≥10 cm dbh on a 20-ha forest plot in China. We found that higher elevation was correlated to changes in mean and reduced diversity of five traits, possibly due to frequent disturbances at higher elevations that favored fast-growing, poorly defended species with high SLA. Maximum dbh showed phylogenetic conservatism but high diversity among co-occurring species, suggesting adult stature is an important axis of within-quadrat niche partitioning. At the individual level, trait patterns were qualitatively consistent but were stronger than species-level patterns, especially for the leaf traits with the greatest intraspecific variation (SLA and succulence). Individual-level SLA exhibited the strongest evidence for both traits among and within-quadrat niche partitioning and indicated elevational filtering. Local niche partitioning and elevational filtering likely play an important role in maintaining species and functional diversity in the most speciose genus at our study site. Our results highlight the importance of individual variation, as it may reveal otherwise obscured niche effects. [ABSTRACT FROM AUTHOR]

Ecology Letters (2012) Abstract Anthropogenic perturbations may affect biodiversity and ecological stability as well as their relationships. However, diversity-stability patterns and associated mechanisms under human disturbances have rarely been explored. We conducted a 7-year field experiment examining the effects of mowing and nutrient addition on the diversity and temporal stability of herbaceous plant communities in a temperate steppe in northern China. Mowing increased population and community stability, whereas nutrient addition had the opposite effects. Stability exhibited positive relationships with species richness at population, functional group and community levels. Treatments did not alter these positive diversity-stability relationships, which were associated with the stabilising effect of species richness on component populations, species asynchrony and portfolio effects. Despite the difficulty of pinpointing causal mechanisms of diversity-stability patterns observed in nature, our results suggest that diversity may still be a useful predictor of the stability of ecosystems confronted with anthropogenic disturbances. [ABSTRACT FROM AUTHOR]

ABSTRACT The Yangtze floodplain is characterized by numerous large (surface area > 1 km2; ∼25% are > 10 km2) and shallow lakes (maximum depth mainly < 5 m). Floodplain lakes are inherently dynamic and important sites for biogeochemical cycling, biodiversity as well as human resources. Importantly, the degree of hydrological connectivity between lakes and river channels is affected by climate, geomorphic processes as well as cultural disturbance of the catchment. This study investigated the long-term (∼200 years) interaction between a shallow floodplain lake (Taibai Lake; area 25 km2, mean depth 3·2 m) and the Yangtze River using high-resolution multi-proxy analysis (diatoms, geochemistry, and grain size) of a 210Pb-dated sediment core. Diatom assemblages in Taibai Lake exhibited a strong temporal succession and were successively dominated by Aulacoseira granulata (planktonic), Gyrosigma acuminatum (periphytic), and the facultatively planktonic Nitzschia palea over the past 200 years. Eutrophication as inferred by diatom inferred-total phosphorous (DI-TP), however, only started around 1990 with TP concentration increasing from 65 to 95 µg L−1. Prior to 1950 DI-TP was constant and detrended correspondence analysis axis 1 sample scores (of the diatom assemblages) were not correlated with DI-TP concentration suggesting that there were other stressors driving changes in the diatom assemblage besides nutrients. We used sediment grain size as a proxy for hydrological connectivity; median grain size is strongly correlated with the abundance of A. granulata ( R2 = 0·67). A comparison of the diatom stratigraphy with physical and geochemical proxies suggested that Taibai Lake shifted from a riverine-influenced, turbid algae-macrophyte mixed state to a clearwater macrophyte-dominated state around 1950 AD, primarily due to the changes in the hydrological regime of the floodplain resulting from land reclamation and building of reservoirs. After 1990 AD, the lake ecosystem deteriorated following continuous input of nutrients from agriculture and aquaculture, shifting to a hyper-eutrophic algae-dominated state. These results indicate the dynamic nature of floodplain ecosystems and the complexity of multiple stressors affecting them over decadal timescales and the long-term interaction between anthropogenic and natural forcing processes. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Indigenous ecological knowledge (IEK) can contribute to the management of local ecosystems and landscapes. Cultural landscapes are produced by and reflect the long-term interactions between humans and nature in indigenous societies. Yunnan Province, located in southwestern China, is the homeland of many ethnic groups, and is also a refuge for numerous species of wild plants and animals. Indigenous people in Yunnan, who have rich ecological knowledge, play an important role in the conservation of local biodiversity and the region's unique terraced agricultural landscapes. We used the Hani people and their outstanding cultural landscape of rice terraces in Yuanyang County of Yunnan Province as a case study to describe their worldview and discuss their formation of IEK; their roles in the preservation of rice landraces and in pest regulation; their management of water, forest, and soil resources; and the vertical landscape pattern and resource-circulation system that has evolved in the areas managed by the Hani. We also discuss the challenges and threats facing the Hani, their IEK, and their cultural landscape, as well as discuss the potential for integration of the Hani's IEK with modern conservation efforts. [ABSTRACT FROM AUTHOR]

This study investigated the taxonomic identities and diversity of fungal endophytes isolated from four Rhizophoraceae mangrove plant species, Ceriops tagal, Rhizophora apiculata, R. stylosa and Bruguiera sexangula var. rhynchopetala, using a combination of morphological and molecular approaches. Two hundred ninety-five isolates were classified into 38 taxa by morphological characteristics. The representative 38 isolates from each taxa were selected for further molecular identification using nuclear ribosomal DNA sequences, including both the internal transcribed spacers (ITS1 and ITS2) and the 5.8S gene region. The 38 representative endophytes were identified to various taxonomic levels. These results suggest that Pestalotiopsis and Phomopsis were the most frequent endophytes in the four host species. Some of the endophytes exhibit host and tissue specificity. The colonization frequencies of endophytic fungi in the stems of the four host plants are evidently higher than in the roots. The four Rhizophoraceae mangrove species have low similarities of endophyte communities. [ABSTRACT FROM AUTHOR]

Carbon (C) sequestration in terrestrial ecosystems can play a role in counteracting the rapid increase in CO concentration in the atmosphere. In this study, soils were sampled from some 2700 sites under contrasting land uses in four selected landscape units as representatives of the lowland (LL), low hill (LH), high hill (HH) and karst mountain (KM) areas in subtropical China. The aim was to quantify the potential for C sequestration in paddy ecosystems in the region. The mean values of organic C stocks in paddy soils (0-20 cm) in the landscape units varied from 37.8 to 60.4 t ha, and were considerably larger than those for soils under arable cropping and orchard managements, and even under woodland except in the KM landscape unit. In the LH unit, the mean organic C concentration in paddy soils increased by 1.67 times ( P < 0.05) during the period between 1979 and 2003. This increase was consistent with the prolonged increase (since the 1950s) in rice productivity in the region. It is concluded that paddy ecosystems in subtropical China have the ability to accumulate organic C faster than other ecosystems. Because these landscape units represent the real situation in paddy ecosystems under farmers' practices for rice production, the data confirm that prolonged organic C accumulation in paddy soils has occurred in subtropical China. [ABSTRACT FROM AUTHOR]

We compared species composition and diversity of the soil seed and seedling banks in three secondary vegetation types (shrubland, Populus bonatii forest, Lithocarpus regrowth forest) and a primary old-growth forest in the subtropical Ailao Mountains of southwestern China to clarify the importance of seed and seedling banks for forest dynamics. The average species richness was the highest in soil samples from the shrubland (26.80 ± 1.98), and the lowest from the primary forest (9.93 ± 0.50). The density of germinable tree seeds increased from the secondary vegetation to the primary forest, and the density of shrub, forb, and graminoid seeds decreased significantly. The most abundant seedlings recorded in soil samples were light-demanding species in the shrubland and Populus bonatii forest. For ground flora, the number of shrub seedlings strongly decreased with the increase in stand age, and shade-tolerant tree seedlings tended to increase. The species similarity between the seed bank and the aboveground vegetation in all sites was low (Sørensen's index = 0.11-0.33), however, the shrubland had higher similarity compared with the other three plant communities. In the primary forest, light-demanding woody species dominated in soil seed banks, while shade-tolerant species dominated in the overstory and the forest floor. In the primary forest, seedlings of dominant tree species were rare in the understory, and no seeds of the dominant species were found in the soil. Results indicated that the early stages of vegetation recovery should take into account the possibility of recovering soil seed bank processes. However, colonization and establishment of tree seedlings will be difficult once a primary forest is destroyed. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the biogeochemical characterization and reclamation strategies for ecosystem in the saline sodic soil of the western part of the Songnen plain, Northeastern China. Findings indicated that the physical and chemical qualities of saline sodic soil can be improved by applying farm yard manure, regenerating salt tolerant grasses and leaching with groundwater. Statistics of nutrients in the saline sodic soils are presented.

The article presents a study which investigates the effect of climate change on terrestrial ecosystem in China. The study employs various data and methods which include the 1961-2100 projected climatic data to lessen data noise and the atmospheric-vegetation interaction model (AVIM2) to simulate terrestrial ecosystem. Moreover, the study reveals that the net primary productivity (NPP) decreases when the projected temperature increases.

Landscape planning is clearly ecologically and socially relevant. Concern about sustainability between human and environment is now a driving paradigm for this professional. However, the explosion of the sustainable landscape in China is a very recent phenomenon. What is the sustainable landscape? How is this realized in practice? In this article, on the basis of the reviews of history and perplexities of Chinese landscape and nature analysis of sustainable landscape, the ecothinking model, an implemental tool for sustainable landscape, was developed, which applies ecothinking in vision, culture, conservation and development of site, and the process of public participation for a harmonious relationship between human and environment. And a case study of the south entrance of TongNiuling Scenic Area was carried out, in which the most optimum scenario was chosen from among three models according to the ecothinking model, to illustrate the construction of the ecothinking model and how to achieve a sustainable landscape. [ABSTRACT FROM AUTHOR]

The article presents a study on the impact of land use on distributed hydrological processes in a wetland-based ecosystem in Jilin, China. The study used Water and Energy Transfer between Soil, Plants and the Atmosphere under quasi-Steady-State (WetSpass) and MODFLOW model to simulate the water balance components of distributed recharge, runoff and evapotranspiration (ET). The study found that ET-limiting land/water resources are critical factors for the preservation of wetland-based ecosystem.

Conserving fish in lakes requires the systematic analysis and assessment of fish species. The issues, conservation needs and fish assemblage changes are described for Lake Qionghai (China). The annual fishery production (AFP) was analysed from 1949 to 2003, which indicated a high disturbance of the aquatic ecosystem in Lake Qionghai caused especially by fisheries. The continuous increase in AFP and the introduction of economically important fish species have changed the fish species structure and diversity of the lake. Only five of 20 native fish species remained extant in 2003. The alien species accounted for 83.58% of the total fish production in 2003. Scoring criteria for 10 indexes of biotic integrity (IBI metrics) were selected for Lake Qionghai. The overall IBI score decreased from 40 in the 1940s to 26 in the 1980s to 20 in 2003. Changes in biotic condition were mainly caused by the destruction of fish physical habitat, pollution, bycatch and the invasion of alien species. Based on the IBI analysis, an ecosystem approach was developed for fish conservation in Lake Qionghai, including conservation at the watershed scale, habitat improvement and restoration, rebuilding of aquatic ecosystems and adaptive ecosystem-based fishery management. [ABSTRACT FROM AUTHOR]