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This REgional Carbon Cycle Assessment and Processes regional study provides a synthesis of the carbon balance of terrestrial ecosystems in East Asia, a region comprised of China, Japan, North- and South-Korea, and Mongolia. We estimate the current terrestrial carbon balance of East Asia and its driving mechanisms during 1990-2009 using three di?erent approaches: inventories combined with satellite greenness measurements, terrestrial ecosystem carbon cycle models and atmospheric inversion models. The magnitudes of East Asia's natural carbon sink from these three approaches are comparable: -0.264±0.033 PgC yr-1 from inventory-remote sensing model-data fusion approach, -0.393±0.141 PgC yr-1 (not considering biofuel emissions) or -0.204±0.141 PgC yr-1 (considering biofuel emissions) for carbon cycle models, and -0.270±0.507 PgC yr-1 for atmospheric inverse models. The ensemble of ecosystem modeling based analyses further suggests that at the regional scale, climate change and rising atmospheric CO2 together resulted in a carbon sink of -0.289±0.135 PgC yr-1 , while land use change and nitrogen deposition had a contribution of -0.013±0.029 PgCyr and -0.107±0.025 PgC yr-1 , respectively. Although the magnitude of climate change effects on the carbon balance varies among different models, all models agree that in response to climate change alone, southern China experienced an increase in carbon storage from 1990 to 2009, while northern East Asia including Mongolia and north China showed a decrease in carbon storage. Overall, our results suggest that about 13-26% of East Asia's CO2 emissions from fossil fuel burning have been offset by carbon accumulation in its terrestrial ecosystems over the period from 1990 to 2009. The underlying mechanisms of carbon sink over East Asia still remain largely uncertain, given the diversity and intensity of land management processes, and the regional conjunction of many drivers such as nutrient deposition, climate, atmospheric pollution and CO2 changes, which cannot be considered as independent for their effects on carbon storage. [ABSTRACT FROM AUTHOR]

The issue of biological invasions in aquatic ecosystems is becoming increasingly severe in the contemporary world. Due to the lack of monitoring and management systems for aquatic invasive species, the difficulty in identifying aquatic invasive species, and the limited effectiveness of conventional control methods in aquatic environments, biological control in water bodies is comparatively more challenging than other types of interventions. In recent years, environmental DNA (eDNA) survey methods have rapidly developed in various fields, such as biological monitoring, community ecology, paleoenvironmental research, conservation biology, and invasion ecology, due to their unique advantages of being rapid, sensitive, efficient, and non-invasive. Because of these characteristics, this innovative molecular approach has gained wider acceptance and is being increasingly utilized for the detection of biological diversity in aquatic environments. Furthermore, it has emerged as a novel technology to address the pressing and significant issue of aquatic invasive species in the vast freshwater and marine resources of the East Asian region. This paper summarizes a variety of literature sources to summarize the major aquatic invasive species in East Asian countries and the current application status of eDNA technology in their survey processes. Using China as a case study, it expounds on the prospective incorporation of the 4E strategy with eDNA technology for the surveillance of biological invasions. Furthermore, it explores the potential prospects of eDNA technology in species diversity management and policy formulation, offering theoretical guidance for establishing aquatic invasive species monitoring systems. From a technological standpoint, the integration of eDNA technology with the 4E strategy holds significant potential for application, thereby offering a promising reference for the formulation of policies related to the management of aquatic biological invasions and biodiversity. [ABSTRACT FROM AUTHOR]

We present the largest freely available EcoPlate dataset for Japan, comprising data collected from a network of 33 natural forest sites (77 plots) in regions of East Asia ranging from cool temperate to subtropical. EcoPlate is a 96‐well microplate that contains three repeated sets of 31 response wells with different sole carbon substrates. The utilization of each carbon substrate by the microbial community is quantified by the color density of the well during incubation. EcoPlate can provide a multifunctional index of a soil microbial community. Soil properties (water content, carbon [C] and nitrogen [N] contents, the C/N ratio, and pH) that are essential for interpreting the EcoPlate results were also measured. The network is part of the Forest and Grassland Survey of the Monitoring Sites 1000 Project established by the Ministry of the Environment. Using a standardized protocol, soil was sampled between September and December 2020. A preliminary principal component analysis was performed on the temporal integration of color density using 31 substrates. For the temporal integration, we calculated the cumulative amount of color development by integrating the color density development curve. PC1 contributed 55.6% and is thought to represent the magnitude of the overall absorbance of all substrates. The model of environmental factors including elevation and the model of soil properties, including water content and pH, were selected as the best‐fit models for variation in PC1. EcoPlate data enable the meta‐analysis of comparative studies among forest types and testing community ecology and ecosystem function hypotheses at broad spatial scales. The complete data set for this abstract published in the Data Paper section of the journal is available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP‐2022‐01.1/jalter‐en. [ABSTRACT FROM AUTHOR]

In community ecology, trait‐based approaches have been strongly recommended in recent years to understand the responses of community functions against environmental changes. Trait‐based approaches have been used to solve the mechanistic rules in the relationship between soil animal communities and environmental change. However, databases of functional traits of soil animals are still lacking. Collembola is one of the most abundant and diverse group in land ecosystems, with more than 400 identified species in Japan. This data set provides taxonomic information, geographic, habitat distributions and 13 morphological trait items of 407 species of Japanese Collembola: described in Japanese literature. The workshop of Japanese Collembola, supported by the Japanese Society of Soil Zoology, summarized the taxonomy for the Japanese Collembola species. The data set presented here is mainly based on their work. The spatial coverage of this data set is in the land area of Japan. Suborder, superfamily, family, subfamily, genus and species names, as well as common Japanese names, are listed in this paper. The species distributions of Japanese Collembola in each global ecozone and in each area within Japan were described. Habitat preference for soil, cave, seashore and tree trunk habitats was recorded. The 13 morphological traits of Collembola species, which are body length; body weight of adult individual; body form; antenna length; furca length; body pigmentation; pairs of ocelli (eyes); post‐antennal organ; pseudocelli; body scale; anal spine; mandible and molar plate are listed in this dataset. These 13 morphological traits in this dataset are covered the most of trait items which have been internationally used in Collembola study. Trait‐based studies of Collembola have mainly been for European species, most of which are not found in Japan or East Asia. These data sets may provide an important first step to incorporating community data from the Asian region to the trait‐based global ecology. Data files are stored in the Ecological Research Data Archives at http://db.cger.nies.go.jp/JaLTER/ER_DataPapers/archives/2019/ERDP-2019-03. [ABSTRACT FROM AUTHOR]

A regional coupled soil–vegetation–atmosphere model is used to study changes and interactions between climate and the ecosystem in East Asia due to increased atmospheric CO[sub 2] . The largest simulated climate changes are due to the radiative influence of CO[sub 2] , modified slightly by vegetation feedbacks. Annual precipitation increases by about 20% in coastal areas of northern China and in central China, but only by 8% in southern China. The strongest warming of up to 4°C occurs in summer in northern China. Generally, the climate tends to be warmer and wetter under doubled CO[sub 2] except for inland areas of northern China, where it becomes warmer and drier. Most of the changes discussed in this paper are associated with changes in the East Asian monsoon, which is intensified under doubled CO[sub 2] . The largest changes and feedbacks between vegetation and climate occur in northern China. In some coastal and central areas around 40°N, temperate deciduous forests expand northward, replacing grassland due to warmer and wetter climate. Evergreen taiga retreats in the coastal northeast, causing extra cooling feedback due to less snow masking. The largest changes occur in extensive inland regions northward of 40°N, where deserts and shrub land expand due to warmer and drier conditions, and water supply is a critical factor for vegetation. These northern inland ecosystems experience considerable degradation and desertification, indicating a marked sensitivity and vulnerability to climatic change. [ABSTRACT FROM AUTHOR]

Caves are home to unique and fragile biotas with high levels of endemism. However, little is known about how the biotic colonization of caves has developed over time, especially in caves from middle and low latitudes. Subtropical East Asia holds the world's largest karst landform with numerous ancient caves, which harbor a high diversity of cave-dwelling organisms and are regarded as a biodiversity hotspot. Here, we assess the temporal dynamics of biotic colonization of subtropical East Asian caves through a multi-taxon analysis with representatives of green plants, animals, and fungi. We then investigate the consequences of paleonviromental changes on the colonization dynamics of these caves in combination with reconstructions of vegetation, temperature, and precipitation. We discover that 88% of cave colonization events occurred after the Oligocene-Miocene boundary, and organisms from the surrounding forest were a major source for subtropical East Asian cave biodiversity. Biotic colonization of subtropical East Asian caves during the Neogene was subject to periods of acceleration and decrease, in conjunction with large-scale, seasonal climatic changes and evolution of local forests. This study highlights the long-term evolutionary interaction between surface and cave biotas; our climate-vegetation-relict model proposed for the subtropical East Asian cave biota may help explain the evolutionary origins of other mid-latitude subterranean biotas. [ABSTRACT FROM AUTHOR]

A fossil eudicot, Gansufructus saligna gen. et sp. nov. is reported from the Early Cretaceous (late Aptian–early Albian) of the Gansu Province, Northwest China, based on numerous well-preserved axes with attached leaves and infructescences. The leaves are alternate, short petiolate and linear-lanceolate with low rank pinnate to reticulate venation. The infructescences are loose panicles bearing fruits in different stages of maturity, each containing four partly free carpels borne in a whorled arrangement. Each carpel has three to five seeds borne along its ventral margin. The nature of the leaves and axes indicates a terrestrial, herbaceous habit. In general organization, Gansufructus is closely similar to the fruit-bearing axes of Sinocarpus decussatus from the Early Cretaceous Jehol Biota, as well as other more or less contemporaneous angiosperms from the Far East, which together provide evidence of diverse eudicot angiosperms of low stature colonizing areas close to environments of deposition. [ABSTRACT FROM AUTHOR]

In many East Asia regions, spring (from March to May) precipitation is an important restricting factor to vegetation growth, and atmospheric circulation system may influence spring precipitation patter. It is helpful to under the response of ecosystem to climate change by studying the influence of atmospheric circulation system on the coupling relationship between spring net primary productivity and precipitation. Driving CASA (Carnegie-Ames-Stanford Approach) NPP (Net Primary Productivity) model, we estimated spring NPP for East Asia area (70°E–1 70°E, 10°N–70°N) from 1982 to 1999, and by the method of singular value decomposition we further analyzed the coupling features of spring NPP with precipitation. The result showed that the response features of NPP to precipitation were mainly embodied within the leading six NPP-precipitation paired-modes. The interpretation rates of the leading six paired-modes to the covariance of NPP-precipitation were 42.91, 23.29, 9.96, 5.60, 5.04 and 3.95%, respectively, and total to 90.75%. The temporal correlation coefficients of the leading six paired-modes were 0.830, 0.889, 0.841, 0.747, 0.912 and 0.923, respectively, and all the correlations were significant at significant level of 0.001. In some high latitude regions, there was no obviously corresponding relationship between NPP and precipitation in the leading two paired-modes, and the reason of it may be that spring temperature was the main restricting factor to NPP. In middle and low latitude regions, the effect of precipitation on NPP was relatively more notable. Nine atmospheric circulation factors in spring affected the patterns of NPP and precipitation greatly, and the regions with interpretation rate over 50% shared 60.41 and 65.58% of the whole study area, respectively. [ABSTRACT FROM AUTHOR]

The pattern of species abundance, represented by the number of individuals per species within an ecological community, is one of the fundamental characteristics of biodiversity. However, despite their obvious significance in ecology and biogeography, there is still no clear understanding of these patterns at large spatial scales. Here, we develop a hierarchical modelling approach to estimate macroscale patterns of species abundance. Using this approach, estimates of absolute abundance of 1248 woody plant species at a 10-km-grid-square resolution over East Asian islands across subtropical to temperate biomes are obtained. We provide two examples of the basic and applied use of the estimated species abundance for (1) inference of macroevolutionary processes underpinning regional biodiversity patterns and (2) quantitative community-wide assessment of a national red list. These results highlight the potential of the elucidation of macroscale species abundance that has thus far been an inaccessible but critical property of biodiversity. Measurement of species abundance is fundamental in ecology, yet challenging at large spatial scales. Here, the authors show estimates of abundance of 1248 woody plant species over the East Asian islands that highlight macroevolutionary processes of biodiversity and the status of the national red listing. [ABSTRACT FROM AUTHOR]

The most studied sections of the Triassic sequences in the lithotectonic zones along the Mongol–Okhotsk fold system from Eastern Transbaikalia to the Sea of Okhotsk are described. Changes in the composition, thickness, and characteristic biota are traced. Transgressive and regressive evolution stages are defined. The presented modern ideas on the geology of this region can serve as a reliable basis for geodynamic and metallogenic reconstructions. [ABSTRACT FROM AUTHOR]

An analysis is made of the changes in biotic components of landscapes during the Holocene Little Climatic Optimum on the island and mainland shores of the southern Far East which manifested themselves in all landscape zones. Some paleoclimatic parameters and the shift of landscape zones have been assessed. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated atmospheric deposition as an important source of bioreactive compounds to the ocean. The South China Sea (SCS), where aerosol loading is among the highest in the world, however, is poorly studied, particularly on the in situ response of phytoplankton community structures to atmospheric deposition. By conducting a series of microcosm bioassays at different hydrographical locations and simulating different aerosol event scales, we observed both positive and negative responses to the input of East Asian (EA) aerosol with high nitrogen (N) and trace metal contents, in terms of biomass, composition and physiological characteristics of phytoplankton communities. High levels of aerosol loading relieved phytoplankton nitrogen and trace metal limitations in SCS, and thus increased total phytoplankton biomass, enhanced their physiological indicators (e.g. photosynthetic efficiency) and shifted phytoplankton assemblages from being dominated by picoplankton to microphytoplanton, especially diatoms. However, under low levels of aerosol loading, the composition shift and biomass accumulation were not apparent, suggesting that the stimulation effects might be counterbalanced by enhanced grazing mortality indicated by increased abundance of protist grazers. Trace metal toxicity of the aerosols might also be the reason for the reduction of picocyanobacteria when amended with high EA aerosols. The magnitude and duration of the deposition event, as well as the hydrographical and trophic conditions of receiving waters are also important factors when predicting the influence of an aerosol deposition event. Our results demonstrated different responses of phytoplankton and microbial food web dynamics to different scales of atmospheric input events in SCS and highlighted the need for achieving an accurate comprehension of atmospheric nutrient on the biogeochemical cycles of the oceans. [ABSTRACT FROM AUTHOR]

We examined effects of seasonality of climate and dominant life form (evergreen/deciduous, broad-leaf/coniferous) together with energy condition on species diversity, forest structure, forest dynamics, and productivity of forest ecosystems by comparing the patterns of changes in these ecosystem attributes along altitudinal gradients in tropical regions without seasonality and along a latitudinal gradient from tropical to temperate regions in humid East Asia. We used warmth index (temperature sum during growing season, WI) as an index of energy condition common to both altitudinal and latitudinal gradients. There were apparent differences in patterns of changes in the ecosystem attributes in relation to WI among four forest formations that were classified according to dominant life form and climatic zone (tropical/temperate). Many of the ecosystem attributes-Fisher’s alpha of species-diversity indices, maximum tree height and stem density, productivity [increment rate of aboveground biomass (AGB)], and population and biomass turnover rates-changed sharply with WI in tropical and temperate evergreen broad-leaved forests, but did not change linearly or changed only loosely with WI in temperate deciduous broad-leaved and evergreen coniferous forests. Values of these ecosystem attributes in temperate deciduous broad-leaved and evergreen coniferous forests were higher (stem density was lower) than those in tropical and temperate evergreen broad-leaved forests under colder conditions (WI below 100°C). Present results indicate that seasonality of climate and resultant change in dominant life form work to buffer the effects of energy reduction on ecosystem attributes along latitudinal gradients. [ABSTRACT FROM AUTHOR]