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PurposeWhile the peer effects of technology adoption are well established, few studies have considered the variation in peer effects resulting from the mutual proximity between leaders and followers and the heterogeneity of farmers' learning technology. This study addresses the gap in the literature by analyzing the peer effects of technology adoption among Chinese farmers.Design/methodology/approachDrawing on a government-led soil testing and formulated fertilization program, this study uses survey data of farmers from three Chinese provinces to examine the peer effects of technology adoption. This study uses a probit model to examine how mutual proximity influences peer effects and their heterogeneity. Accordingly, farmers were divided into two groups, namely small- and large-scale farmers, and then into leaders or followers depending on whether they were selected by the government as model farmers.FindingsBoth small- and large-scale farmers are more likely to use formula fertilizer if their peers do so. However, a large-scale farmer is more likely to adopt formula fertilizer if the average adoption behavior of other large-scale model (leader) farmers is higher, while a small-scale farmer is more likely to adopt formula fertilizer if other small-scale non-model (follower) farmers have higher average adoption behavior. Moreover, the peer effect was weakened by geographic distance among small-scale farmers and by economic distance among large-scale farmers.Originality/valueThis study elucidates the means of optimizing social learning and technology adoption among farmers.

Recent climate change and vegetation greening have important implications for global terrestrial hydrological cycles and other ecosystem functions, raising concerns about the watershed water supply capacity for large water diversion projects. To address this emerging concern, we built a hybrid model based on the Coupled Carbon and Water (CCW) and Water Supply Stress Index (WaSSI) models and conducted a case study on the upper Han River basin (UHRB) in Central China that serves as the water source area to the middle route of the South-to-North Water Diversion Project (SNWDP). Significant vegetation greening occurred in the UHRB during 2001–2018, largely driven by the widespread afforestation in the region, with the normalized difference vegetation index increasing at a rate of 0.5±0.1 % yr−1 (p<0.05) but with no significant trends in climate during the same period (albeit with large interannual variability). Annual water yield greatly decreased, and vegetation greening alone induced a significant decrease in water yield of 3.2±1.0 mm yr−1 (p<0.05). Vegetation greening could potentially reduce the annual water supply by 7.3 km3 on average, accounting for 77 % of the intended annual water diversion volume of the SNWDP. Although vegetation greening can bring enormous ecosystem goods and services (e.g., carbon sequestration and water quality improvement), it could aggravate the severity of hydrological drought. Our analysis indicated that vegetation greening in the UHRB reduced about a quarter of water yield on average during drought periods. Given the future warming and drying climate is likely to continue to raise evaporative demand and exert stress on water availability, the potential water yield decline induced by vegetation greening revealed by our study needs to be taken into account in the water resources management over the UHRB while reaping other benefits of forest protection and ecological restoration.

It is widely known how acid rain negatively impacts plant physiology. However, the magnitude of these effects may depend on soil types. Although the response of aboveground parts has received much attention, the effects of soil types and acid rain on underground processes are yet to be studied, specifically with respect to the composition and diversity of bacterial communities in the rhizosphere. Based on a high throughput sequencing approach, this study examined how different soil types, acid rain of different pH, and interactions between the two factors influenced the growth and rhizosphere bacterial communities of Jatropha curcas L. The present study pointed out that the soil pH, total nitrogen (TN), total phosphorus (TP), total potassium (TK), and total organic carbon/total nitrogen (C/N) were more related to soil type than to acid rain. The growth of J. curcas aboveground was mainly affected by acid rain, while the underground growth was mainly influenced by soil type. Changes in bacterial abundance indicated that the genera (Burkholderia-Paraburkholde, Bryobacter, Cupriavidus, Mycobacterium, and Leptospirillu) and phyla (Acidobacteria and Actinobacteria) could likely resist acid rain to some extent, with Acidobacteria, Gemmatimonadetes and Proteobacteria being well adapted to the copiotrophic environments. Results of correlational analyses between Firmicutes and soil properties (pH, TN, TK) further indicated that this phylum was also well adapted to a nutrient-deficient habitat of low pH. Finally, while Mycobacterium and Bradyrhizobium could adapt to low pH, high soil TK contents were not conducive to their enrichment. The results also showed that acid rain shifted the bacterial groups from fast-growing copiotrophic populations to slow-growing oligotrophic ones. The RDA analysis, and Pearson's rank correlation coefficients indicated that soil pH and TK were the main factors influencing bacterial richness.

Given the increasingly fragmented forest landscapes, it is necessary to map forest cover with fine spatial resolution in a large area. The European Space Agency (ESA) released the 10 m global land cover map in 2020 based on Sentinel-1 and Sentinel-2 images, and Dynamic World provides near real-time possibilities of many land cover classes based on Sentinel-2 images, but they are not designed particularly for forest cover. In this research, we aimed to develop a method to automatically estimate an accurate 10 m forest cover map in 2020 by fusing the ESA forest cover map and Dynamic World near real-time forest cover possibilities. The proposed method includes three main steps: (1) generating stable forest samples, (2) determining the threshold T and (3) producing the fused forest cover map. China’s Han River Basin, dominated by complex subtropical forests, was used as the study site to validate the performance of the proposed method. The results show that the proposed method could produce a forest cover map with the best overall accuracy of 98.02% ± 1.20% and more accurate spatial details compared to using only one of the two data sources. The proposed method is thus superior in mapping forest cover in complex forest landscapes.

Code cloning facilitates software development but also causes recurring bugs and software quality problems. Some types of code clones have very low similarity in literal, leading to difficulty of detection. Aiming at this pro-blem, this paper proposes one method of code clone detection based on the program vector tree. First, the feature representations of lexical units are extracted based on a statistical language model and the semantic similarities between different literal words are analyzed. Second, the abstract syntax tree (AST) of each program is extracted by syntactical analysis, and each AST is transformed into a program vector tree with each leaf node assigned a feature representation of the corresponding literal word. Finally, one weighted encoding mechanism is proposed for encoding each program vector tree into a fixed-sized vector, considering different weight information of nodes in the tree, and code fragments with similar vector representations are reported as code clones. Experimental results on BigClone-Bench, an existing large benchmark of real code clones, show that this method outperforms many prominent clone detection methods, including NiCad, Deckard, SourcererCC and Oreo, etc., in detecting Moderately Type-3 or Type-4 clones that have low similarity in literal, which verifies the validity of this method.

Biological nitrogen (N) fixation plays an important role in terrestrial N cycling and represents a key driver of terrestrial net primary productivity (NPP). Despite the importance of N fixation in terrestrial ecosystems, our knowledge regarding the controls on terrestrial N fixation remains poor. Here, we conducted a meta-analysis (based on 852 observations from 158 studies) of N fixation across three types of ecosystems with different status of disturbance (no management, restoration [previously disturbed], and disturbance [currently disturbed]) and in response to multiple environmental change factors (warming, elevated carbon dioxide [CO2 ], increased precipitation, increased drought, increased N deposition, and their combinations). We explored the mechanisms underlying the changes in N fixation by examining the variations in soil physicochemical properties (bulk density, texture, moisture, and pH), plant and microbial characteristics (dominant plant species numbers, plant coverage, and soil microbial biomass), and soil resources (total carbon, total N, total phosphorus (P), inorganic N, and inorganic P). Human disturbance inhibited non-symbiotic N fixation but not symbiotic N fixation. Terrestrial N fixation was stimulated by warming (+152.7%), elevated CO2 (+19.6%), and increased precipitation (+73.1%) but inhibited by increased drought (-30.4%), N deposition (-31.0%), and combinations of available multiple environmental change factors (-14.5%), the extents of which varied among biomes and ecosystem compartments. Human disturbance reduced the N fixation responses to environmental change factors, which was associated with the changes in soil physicochemical properties (2%-56%, p < .001) and the declines in plant and microbial characteristics (3%-49%, p ≤ .003) and soil resources (6%-48%, p ≤ .03). Overall, our findings reveal for the first time the effects of multiple environmental change factors on terrestrial N fixation and indicate the role of human disturbance activities in inhibiting N fixation, which can improve our understanding, modeling, and prediction of terrestrial N budgets, NPP, and ecosystem feedbacks under global change scenarios.

Named entity recognition is an important stage in the construction of knowledge graph. Based on the national military standard and software testing documents, the entity type classification and the data set construction and labeling are completed. In the field of software testing, aiming at the problem that the character and word joint entity recognition method has low recognition precision, the character level feature extraction method is improved, and the CWA-BiLSTM-CRF (character and word attention- bi-directional long short term memory-conditional random field) recognition framework is proposed. The framework consists of two parts: the first part constructs a pre-trained word fusion dictionary, inputs the words and characters together to the bi-directional long short term memory network for training, and adds attention mechanism to measure the semantic contribution of each character in the word to extract the character-level features; the second part, the character-level features and word vectors are spliced, input to the bi-directional long short term memory network for training, and then through the conditional random field to solve the problem of unreasonable sequence of label results, the entities in the text are identified. The experimental results are compared with 3 commonly used deep learning character-level feature extraction methods. Both accuracy and recall rates are improved, and the optimal F1 value is 88.93%. Experiments show that the improved method is suitable for the named entity recognition task in the military software testing field, which lays the foundation for the next construction of the knowledge graph.

Land-use in uplands is an important factor affecting water quality in its respective catchment, and its influences at the different spatial scales and configurations warrant further investigation. Here, we selected 26 catchments in the upper Han River (China) and sampled the surface water at the outlet of each catchment in four seasons during 2019. Multivariate statistics were used to identify the relationships between land use characteristics in uplands and water quality in river system. The results indicated that organic pollution (CODMn), pH, dissolved oxygen (DO), ions concentration (EC), nutrient (i.e., NH+ 4-N, NO- 3-N and dissolved phosphorus (DP) in rivers displayed significant seasonal variations. Stepwise regression revealed that landscape metrics such as Patch Density (PD), Landscape Shape Index (LSI), and Splitting Index (SPLIT) were important factors influencing water quality in rivers regardless of their spatiality and seasonality. Urban was the most frequently appeared land-use type in the best prediction models, and forest area showed a negative correlation with water quality parameters in most cases. Overall, the influence of land-use on river water quality was slightly higher at reach scale than at catchment and riparian scales. Also, nutrients (i.e., NH+ 4-N, NO- 3-N, and DP) in rivers were primarily impacted by the land use characteristic at catchment and riparian scales. Overall, our results suggested that multi-scale explorations would help to achieve a fully understanding on the impacts of land use on river water quality.

Afforestation has been proposed as an effective strategy for restoration and carbon sequestration, however, its impacts on the functions of soils and microbiome remain poorly understood. By analyzing 144 afforestation sites across a 159 000 square kilometer watershed in China, a typical region characterized with rapid forest expansion in global land-use change map, we provided the first large-scale observation evidence that afforestation did not drive net accumulation of soil carbon and nitrogen in two decades. Afforestation significantly shifted the soil microbial community and their functional profiles of element cycling, increased soil prokaryotic diversity but reduced fungal diversity. Afforestation reduced the network complexity of soil prokaryotes but did not change the complexity of fungal networks. Planting introduced- poplar reduced soil multifunctionality while native trees did not change multifunctionality. Our results reveal the ecological responses of soils to afforestation across a broad geographic scale and provide new insights for forest restoration programs.

Acid rain remains a global environmental issue that can indirectly impact plant root growth and health by mediating soil acidification. The impact of acid rain on the roots of Jatropha curcas L., however, has not been thoroughly evaluated to date in soils with a range of buffering capacities. We, therefore, explored the ability of J. curcas roots to tolerate acid rain in a range of soil types by exposing samples to simulated acid rain (SAR) (pH2.5, pH3.5, pH4.5, pH5.6) and then examining the impact of such exposure on root morphology, relative growth rate (RGRroot), nutrient absorption, enzymatic activity, and microbial biomass. Yellow–brown soil (YBS) and purple soil (PS) were found to be better able to buffer SAR-mediated acidification, thereby providing superior benefits to J. curcas root growth as compared to red soil (RS) and yellow soil (YS) under these experimental conditions. SAR (pH 4.5) significantly enhanced Ca, K, and Mg absorption by J. curcas roots, thereby improving their growth characteristics, whereas SAR (pH 2.5) impaired K and Mg absorption and thus suppressed root growth. K and Mg absorption characteristics were regulated by changes in plasma membrane H + -ATPase activity under these different SAR treatment conditions. Morphological and growth (RGRroot) adaptations of J. curcas roots to SAR treatment were associated with superoxide dismutase activity levels therein. SAR (pH 4.5) was sufficient to bolster the rhizosphere microbial activity of J. curcas seedlings, and correlation analyses revealed that root growth was regulated by rhizosphere microbial biomass P content under SAR treatment conditions.

Recent global climate change and vegetation greening have important implications to Earth’s global biogeochemical cycles and climate, raising concern about the water supply of water diversion projects. To quantify how such a greening trend impacts local water balance and the capacity of water supply, we built a hybrid model based on the Coupled Carbon and Water (CCW) and Water Supply Stress Index (WaSSI) models. We conducted a case study using the Upper Han River basin (UHRB) in southern China that serves as the water source area to the middle route of the South-North Water Diversion Project (SNWDP). Significant vegetation greening occurred in the UHRB during 2001–2018, with the normalized difference vegetation index increasing at a rate of 0.5 % yr−1 (p

QUESTIONS: What are the primary types of intraspecific distribution patterns and interspecific associations of tree species in the temperate–subtropical transition region? Can potential ecological mechanisms such as habitat heterogeneity, dispersal limitation, density dependence, spatial segregation, and competition between species regulate these patterns? LOCATION: The Qinling Mountains, north‐central China. METHODS: Ripley's K‐function, D‐function and pair correlation function were applied to assess the spatial distribution of 15 dominant tree species in a fully mapped 25‐ha plot. Complete spatial randomness (CSR), heterogeneous Poisson (HP) and random‐labelling (RL) null models were used to reveal the potential process of community construction. RESULTS: (a) Thirteen of 15 adult tree species displayed an aggregation distribution at various scales. (b) Eleven adult species (73.3%) showed significant aggregation, especially at small distances, after removing the effect of habitat. (c) The percentage of species showing additional aggregation relative to adults decreased from saplings to juveniles. The maximum strength of density dependence was negative with species abundance. (d) Only 29 (13.8%) of the species pairs showed significant small‐scale interactions. Most of the significant small‐scale associations did not occur in abundant species pairs. (e) Negative interactions of interspecific associations were more prevalent than positive ones, yet there was no consistency of the characteristics among species pairs. CONCLUSIONS: Habitat heterogeneity and dispersal limitation likely contribute to the spatial pattern of tree species at different life stages. Density dependence remains the important factor in maintaining species diversity in this forest stand. Moreover, spatial segregation generates the interspecific spatial patterns of segregation and partial overlap. Unexpectedly, the species herd protection hypothesis and the low‐frequency hypothesis cannot well explain the mechanism of interspecific interaction at small distances. Resource competition might be responsible for negative associations being more frequent among species pairs.

Agricultural abandonment has been taken as one of the most widely used strategies for ecological restoration. Abandoned croplands expanded worldwide since the middle of the twentieth century and will increase considerably in the future. Whether agricultural abandonment alters the abundances of soil carbon (C) and nitrogen (N) mineralization genes, and whether these functional genes are linked to alterations in C and N mineralization rates remain unknown. We took advantage of a well-established chronosequence of nature restoration sites on abandoned croplands which represent a century of vegetation succession in China’s Qinling Mountains, to determine soil C and N mineralization rates, and their relationships with vegetation succession, edaphic characteristics, soil microbial communities, and functional genes based on GeoChip 5.0. We found that soil C and N mineralization rates, microbial biomass and composition, and the number and abundances of functional genes were significantly affected by vegetation succession following agricultural abandonment. Soil C and N mineralization rates increased by sixfold and threefold, respectively, along the cropland to forest successional gradient. The NO3-N, NH4-N and soil available phosphorus (P) concentrations were important factors associated with the C and N mineralization genes. The shifts in edaphic environments (i.e., soil moisture, cation exchange capacity, and C/P ratio), vegetation-derived substrates (i.e., soil organic C and N), and soil microbial composition (i.e., Fungi/Bacteria ratio, amounts of Gram-negative bacteria, Actinomycetes, and arbuscular mycorrhizal fungi), rather than the abundances of functional genes involved in mineralization processes, controlled soil C and N mineralization rates along the long-term vegetation successional gradient. Abandoning cropland for natural succession could facilitate the recuperation of soil C and N processes and alter soil microbial composition and functional genes. The abundances of microbial functional genes are less important than previously expected in regulating soil C and N mineralization rates.

A methodology for carbon accounting and net mitigation estimation for national ecological restoration projects in China (CANM-EP) was developed, and this method simultaneously considered carbon sequestration, on-site greenhouse gas (GHG) emissions from ecosystem management, off-site GHG emissions and other changes in the ecosystem GHG budget. Based on this methodology, the annual variance and composition of carbon sequestration, GHG emissions and net carbon sequestration were analyzed for the first stage of the Beijing-Tianjin Sand Source Control Project (BTSSCP) (2001–2010) in the respective project provinces. The total carbon sequestration in the BTSSCP from 2001 to 2010 was 71.25–71.66 Tg C, and the additional GHG emissions from the BTSSCP were 7.28–7.50 Tg Ce, which counteracted 10.2–10.5% of the sequestered carbon. Among the different project measures in their corresponding ecosystems, the counteraction effect of grassland management in the grassland ecosystem was over 50%, which was much higher than that of afforestation and the conversion of cropland to forest. The net carbon sequestration in the BTSSCP was 63.75–64.38 Tg Ce, and the annual average was 6.38–6.44 Tg Ce·yr−1. The annual rate of net carbon mitigation for Beijing, Tianjin, Hebei, Shanxi and Inner Mongolia was 1.16–1.17, 1.29–1.30, 1.06–1.07, 0.85–0.86 and 0.63–0.65 t Ce·ha−1·yr−1, respectively. The GHG emissions offset a minor part of the carbon sequestration in the BTSSCP. Therefore, the BTSSCP makes a relatively significant contribution to GHG mitigation in China.

In present study, berberine proliposomes (ber-PL) of powder state that can form liposomal structure via self-assemble in water was prepared using solution enhanced dispersion by supercritical CO2 (SEDS) to improve the oral bioavailability of berberine. Several important parameters were optimized using Box-Behnken design to get ber-PL with high entrapment efficacy (EE) of 90.3% ± 4.9%. Physicochemical characterization showed the optimum ber-PL was amorphous spherical nanoparticles and could form uniform liposomes around 80 nm easily via hydration. EE was closely related to the particle morphology of ber-PL. In vitro drug release study displayed a sustained release profile, and the drug released faster in neutral condition than acid medium. The oral bioavailability for ber-PL was 22.47 times greater than raw berberine, and the mean residence time of berberine in plasma was extended from 6.82 ± 2.99 to 10.83 ± 2.01 h as well. The proliposome formulated using SEDS is a favorable strategy to improve the bioavailability of berberine.

China began implementing the world’s most ambitious afforestation and forest conservation projects in 2000s. However, whether the forest restoration efforts facilitate forest recovery, and whether the changes in land-use/land-cover (LULC) driven by afforestation projects affect ecosystem services remains poorly understood. Here, we investigated the changes in LULC and water-related ecosystem services (i.e., water yield, water purification, and soil conservation) using the InVEST (Integrated Valuation of Environmental Service and Tradeoffs) model in China’s Han River basin, the water source region of the South-to-North Water Transfer Project (Middle Route). Our study indicated that forest restoration projects greatly facilitated conversion of shrublands and croplands into forests, which dominated the LULC change (LULCC) and subsequently improved the water purification and soil conservation services but slightly decreased water yield services during 2000–2010. By excluding the influence of climatic factors, we found that 4.79 × 108 m3 of water yield were reduced by LULCC, which equals to 0.69% of water yield in 2000. In contrast, the LULCC improved soil conservation services markedly and reduced 1.72 × 107 t sediment, i.e., 12.8% of sediment export in 2000. Meanwhile, 761.7 t nitrogen loading was cut down by the LULCC. The Danjiangkou Reservoir subwatershed, the water supply site for the water transfer project, showed a net decrease of 302 t nitrogen loading from 2000 to 2010. Although the nitrogen loading showed a decreasing trend in 40 out of 50 subwatersheds during 2000–2010, ten subwatersheds showed increasing trends, including the Ren River, Laoguan River, Bai River, Diao River, Youshui River, Tang River, Han River, Xushui River, Sanjia River, and Dan River. These regions should be taken as the priorities for ecosystem restoration and environmental management in the future.

Assessing the corporate green technology progress and environmental governance performance is essential to estimate the technological levels and environment regulation capabilities of enterprises. With the official statistics of collected panel data, we estimate and evaluate the differential levels of provincial corporate green technology and environmental governance performance of industrial enterprises above designated size (IEADSs) in Anhui Province across multiple dimensions. We firstly chose each surveyed city as the decision-making unit (DMU) in data envelopment analysis (DEA). Subsequently, we estimated the green technology efficiency of IEADSs from a static perspective by using the bootstrap DEA model and an improved super-efficiency (SE) DEA model. Secondly, we used the algorithm of Malmquist productivity index to analyze the dynamic efficiency development tendency and spatiotemporal characteristics in the DMUs. From a dynamic perspective, the evolutionary divergence and convergence characteristics of provincial green technology efficiency were brought about by the estimating algorithm of Malmquist productivity index based on the different regional divisions in Anhui Province. Furthermore, in combination with Malmquist-data envelopment analyses, we also used gray correlation analysis to analyze and evaluate the influencing factors of the industrial green technology efficiencies. This study shows many interesting findings across multiple dimensions. Among the 16 DMUs, there are only eight with the regional green technology efficiencies of IEADSs greater than the expected threshold of 0.9. Nevertheless, the green technology efficiencies of provincial industrial enterprises are still far from the national optimized goals in most of the surveyed cities. The regional green technology efficiencies of IEADSs were ranked as South Anhui > North Anhui > Middle Anhui. The overall average industrial green technology efficiency is 0.8650 in Anhui Province, but the provincial differences of sub-area distribution are relatively large and heterogeneous. The average provincial industrial green technology efficiency appeared as the overall tendency to rise, fall, and then rise, although there is an average bootstrapped Malmquist productivity indices of 1.009 in Anhui Province. Among the declined provincial Malmquist productivity indices, the effch, techch, and sech indices are vital causers of the overall decline of the provincial Malmquist productivity indices. Ultimately, based on all these quantitative estimates and findings, we put forward the following concluding remarks with policy implications and corresponding strategies.

Knowledge on how historical disturbances shaped the long-term development of forests is essential for understanding the present forest structure and for predicting the future forest ecosystem dynamics. In this study, dendroecological methods were used to reconstruct the disturbance history of an old-growth subalpine larch (Larix chinensis) forest in the Qinling Mountains of north-central China. Growth patterns of 690 and 582 increment cores extracted respectively from two climatically and topographically different larch stands in the northern and southern slope of the Qinling Mountains were examined for abrupt increases in radial growth indicating formation of past canopy gaps and for rapid early growth rates indicating recruitment in former canopy gaps. The findings demonstrated that there were no large-scale, stand-replacing disturbances during the past more than two centuries. Low- and medium-severity disturbance events predominated, which were probably caused by windthrows due to strong winds. The stand was unevenly aged, and the recruitment pulses associated with disturbance peaks could be distinguished. There were considerable spatio-temporal differences in disturbance dynamics of the subalpine larch stand between the topographically and climatically different sites, manifesting that the larch stand in the northern slope experienced frequent moderate but rare major disturbance events, contrasting with frequent major and moderate disturbance events in the southern slope. This study provided strong evidences that there were substantial variations in the intensity and frequency of disturbance dynamics, leading to considerable differences in the size and age structures of the subalpine larch forest.

Globally, the rate and extent of cropland abandonment increase greatly since 1950s. Knowledge of soil bacteria and fungi succession during long-term vegetation development is particularly limited for the abandoned croplands. In order to test the effects of agricultural abandonment on soil biota succession, we studied the soil bacterial and fungal composition and diversity in abandoned farmlands across a century of secondary vegetation successional gradient in China’s Qinling Mountains. Using high-throughput sequencing technologies, the soil fungal and bacterial communities were studied in 22 abandoned farmlands, as well as 7 adjacent arable fields representing non-abandoned references. The stand age, i.e., years since agricultural abandonment, affected the soil bacterial and fungal composition and explained 8.7 and 31.6% variations of bacterial and fungal communities (at order level), repectively. The Proteobacteria, dominated by chemoorganotrophic bacteria, kept its absolute dominance status (38.66% - 40.77%) constantly during succession even though the vegetation changed obviously from crop to grass, shrub, and forest. The relative abundances of Acidobacteria, Planctomycetes, Verrucomicrobia, Nitrospirae, and Spirochaetes increased significantly with stand age (i.e., years since abandonment), while the Firmicutes, Actinobacteria, Gemmatimonadetes, Cyanobacteria, and Armatimonadetes showed an opposite trend. A distinct shift in fungal communities from Ascomycota -dominant in young stands to Basidiomycota -dominant in older stands was observed, which could be attributed to the increase of vegetation coverage and soil moisture during succession. The soil bacterial richness and diversity increased logarithmically with increasing stand age and gradually reached equilibrium in late-successional stage. Soil fungal diversity tended to increase in the early successional stages and then followed by a decreasing trend. The soil pH was the most important environmental factor predicating the soil fungal α-diversity measurements. Both the soil bacterial and fungal communities displayed successional trends along with vegetation succession. The soil bacteria and fungi exhibited marked differences in successional pattern during secondary succession following agricultural abandonment.

The long-term stressful utilization of forests and grasslands has led to ecosystem degradation and C loss. Since the late 1970s China has launched six key national ecological restoration projects to protect its environment and restore degraded ecosystems. Here, we conducted a large-scale field investigation and a literature survey of biomass and soil C in China's forest, shrubland, and grassland ecosystems across the regions where the six projects were implemented (∼16% of the country's land area). We investigated the changes in the C stocks of these ecosystems to evaluate the contributions of the projects to the country's C sink between 2001 and 2010. Over this decade, we estimated that the total annual C sink in the project region was 132 Tg C per y (1 Tg = 1012 g), over half of which (74 Tg C per y, 56%) was attributed to the implementation of the projects. Our results demonstrate that these restoration projects have substantially contributed to CO2 mitigation in China.

Icotinib is the first self-developed small molecule drug in China for targeted therapy of non–small cell lung cancer. To date, systematic studies on the pharmacokinetic drug-drug interaction of icotinib were limited. By identifying metabolite generated in human liver microsomes and revealing the contributions of major cytochromes P450 (CYPs) in the formation of major metabolites, the aim of the present work was to understand the mechanisms underlying pharmacokinetic and pharmacological variability in clinic. A liquid chromatography/UV/high-resolution mass spectrometer method was developed to characterize the icotinib metabolites. The formation of 6 major metabolites was studied in recombinant CYP isozymes and human liver microsomes with specific inhibitors to identify the CYPs responsible for icotinib metabolism. The metabolic pathways observed in vitro are consistent with those observed in human. Results demonstrated that the metabolites are predominantly catalyzed by CYP3A4 (77%∼87%), with a moderate contribution from CYP3A5 (5%∼15%) and CYP1A2 (3.7%∼7.5%). The contribution of CYP2C8, 2C9, 2C19, and 2D6 is insignificant. Based on our observations, to minimize drug-drug interaction risk in clinic, coprescription of icotinib with strong CYP3A inhibitors or inducers must be weighed. CYP1A2, a highly inducible enzyme in the smoking population, may also represent a determinant of pharmacokinetic and pharmacological variability of icotinib, especially in lung cancer patients with smoking history.

Land use change has been widely considered as a key driver of global carbon (C) dynamics. However, the impact of agricultural land use change on soil respiration and its 13 C-isotopic signature of CO 2 are not fully understood. Therefore, we conducted a field experiment to investigate the seasonal variation of soil CO 2 flux and its 13 C-isotopic signature and their relationships with biotic factors and abiotic factors under land use conversion from croplands to afforested land (woodland and shrubland) after 30 years. Measurement of CO 2 flux was conducted once a month for a whole year. The results showed that the conversion cropland to afforested land significantly increased soil CO 2 flux and lowered the δ 13 C of soil CO 2 . The soil CO 2 flux showed similar seasonal patterns among land use types with the highest (994.87 mg m −2 h −1 ) in summer and the lowest (25.53 mg m −2 h −1 ) in winter. The soil CO 2 flux was positively related to soil organic C and labile C of topsoil (0–10 cm), as well as soil temperature, whereas the δ 13 C of soil CO 2 emission was positively correlated with the δ 13 C of microbial biomass and negatively correlated with soil temperature. Overall, our results reveal that subject to long-term land use change, soil CO 2 fluxes significantly increase in afforested land due to improved availability of soil C, and its 13 C-isotopic signature are strongly related to isotope signature of plant litter inputs.

The holistic quality evaluation of Traditional Chinese Medicine (TCM) is confronted with significant challenges due to its extreme chemical complexity. In this study, a sensitive strategy based on ultra-high-performance liquid chromatography-triple/time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) and chemometric analysis was established and validated for the qualitative and semi-quantitative analyses of characteristic components in Usnea. First, three mass spectrometry fragmentation patterns of phenolic acid standards were studied and summarized. Then, an extract of this herb was analyzed by the full-scan MS spectra and identified by extracted ion chromatography (XIC). Based on the abovementioned methods, a total of 38 compounds (8 dibenzofurans, 11 didepsides, 13 depsidones, and 6 mono-substituted phenyl rings) were identified. Subsequently, the qualities of Usnea samples from different regions were evaluated by the semi-quantitative analysis based on their relative peak areas. Furthermore, principal component analysis (PCA) was performed to compare the Usnea herbs and to find possible diagnostic chemical components. This novel and powerful strategy could provide a potential approach for the holistic quality control of TCM.

As the development of Yangtze River Delta urban agglomeration has been upgraded to a national level development strategy in China, relevant regions need to pay more attention to the environmental governance issues. Based on the 2013–2018 development data of 41 cities and the established evaluation indicator system with “press-state-response” (PSR) model, we mainly use a combination of global principal component analysis (GPCA) and entropy method to comprehensively measure regional environmental governance performance (EGP) in the Yangtze River Delta urban agglomeration. Next, the spatial relationship is explored and discussed with spatial autocorrelation analysis. Finally, the panel Tobit model is used to perform a regression analysis on the factors affecting the performance of environmental governance in the Yangtze River Delta region. The results are summarized as follows. (1) From 2013 to 2018, the overall environmental governance performance of the Yangtze River Delta region maintained a steady growth trend, of which the environmental governance performance of Jiangsu Province and Shanghai maintained a steady increase, and the environmental governance performance of Anhui and Zhejiang Province fluctuated greatly. (2) These cities with better EGP are mainly located in the central and southern regions of the Yangtze River Delta, and those cities with poor EGP are mainly located in the northern part of the Yangtze River Delta. The environmental governance performance gap between provinces and cities is obviously large, and there are significant spatial positive correlations, spatial spillover effects and a trend of agglomeration with increased volatility. (3) The regression analysis shows that the economic development level has a significant positive impact on the EGP of the Yangtze River Delta region. Meanwhile, the negative impact of industrial structure and foreign investment is significant, but the positive impact of R&D investment intensity is insignificant, on the performance of environmental governance in the Yangtze River Delta region.

Aescin nanoparticles (ANPs) were prepared using solution-enhanced dispersion by supercritical fluids (SEDS) in order to improve the dissolution properties of aescin and avoid complicated salt-forming procedures. Because aescin is a mixture, the effects of the operating conditions on the composition of the ANPs were first investigated. The compositional ratio of the four dominant active components in aescin changed with the pressure at low solution concentrations (5 mg/mL), but remained constant at higher concentrations (>10 mg/mL). Spherical ANPs with an average diameter below 50 nm was obtained at 12 MPa with solution concentration between 10 to 15 mg/mL. The morphology of ANPs was primarily influenced by the concentration and pressure but not affected by the nozzle diameter. The dissolution of aescin was increased by near 5.5 times from raw aescin to ANPs. Compared with the sodium aescinate, the ANPs exhibited the similar dissolution, but had a moderate initial dissolution burst.

Hydrologic pulsing and revegetation strongly affect both denitrification rate and denitrifier communities in riparian zones, yet how they drive the shifts in the denitrifying bacterial community and consequently alter denitrification remains unclear. In this study, we investigated denitrification rate and denitrifier community structure and their abundance in different hydrological pulsing phases and vegetation types (tree, shrub, and herb) in the water-level-fluctuate-zone of the Three Gorges Reservoir, China. Results revealed that hydrologic pulsing greatly affected denitrification rate possibly by regulating the soil NO3−-N concentration, with higher denitrification rate in the reflooding phase in tree soils than that in the saturated and drying phases. Hydrologic pulsing also significantly regulated the abundance and structure of denitrifier communities in herb soils by altering soil temperature, moisture, and NH4+-N. As expected, vegetation types affected the denitrifier communities by altering soil texture, pH, temperature, moisture, soil organic C, and C:N ratio, with higher abundance of nirS genes and higher diversity of nirS and nirK genes in herb soils. However, there was no significant relationship between denitrification rate and denitrifier communities, indicating that hydrologic pulsing regulated denitrification rate primarily by changing soil environmental factors rather than community composition or abundance of denitrifiers. Our results suggest that tree and herb plantations would potentially improve water quality in the riparian zone and adjacent rivers by increasing denitrification rate and abundance of denitrifiers, respectively.

With the completion of the Danjiangkou Dam, the impoundment and drainage of dams can significantly alter shorelines, hydrological regime, and sediment and can result in the loss of soil and original riparian vegetation. Revegetation may affect soil properties and have broad important implications both for ecological services and soil recovery. In this work, we investigated the soil properties under different restoration approaches, and before and after submergence in the water level fluctuation zone (WLFZ) of the Danjiangkou Reservoir. Soil physical (bulk density and soil moisture), chemical (pH, soil organic carbon, nitrogen, phosphorus and potassium contents), and heavy metals were determined. This study reported that restoration approaches have impacts on soil moisture, pH, N, soil organic carbon, P, K and heavy metals in the WLFZ of the Danjiangkou Reservoir. Our results indicated that different restoration approaches could increase the soil moisture while decrease soil pH. Higher soil organic carbon in propagule banks transplantation (PBT) and shrubs restoration (SR) indicate that PBT and SR may provide soil organic matter more quickly than trees restoration (TR). SR and TR could significantly improve the soil total P and available P. PBT and SR could improve the soil total K and available K. SR and TR could significantly promote Cu and Zn adsorption, and Pb and Fe release by plant. Submergence could significantly affect the soil pH, NO3－-N, NH4＋-N, total P and available P. Submergence could promote NO3－-N and available P adsorption, and NH4＋-N and total P release by soil. The soil quality index (SQI) values implied that TR and PBT greatly improved soil quality. The present study suggests that PBT and TR could be effective for soil restoration in WLFZ of the Danjiangkou Reservoir.

Ponicidin is an active natural ent-kaurane diterpenoid ingredient originating from many Isondon herbs and is expected to become a new anticancer agent. In this study, a practical strategy was developed for the identification of ponicidin metabolites in vivo and in vitro utilizing ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). The analytical strategy was as follows: potential ponicidin metabolites were detected by a novel on-line data acquisition approach, i.e., sequential window acquisition of all theoretical fragment-ion spectra (SWATH™). Compared to the traditional information-dependent acquisition (IDA) method, SWATH™ significantly improved the hit rate of low-level or trace metabolites because it could obtain all MS/MS spectra. Moreover, many data post-processing methods were used to deduce the metabolites structures. As a result, a total of 20 metabolites were characterized in vivo and in vitro. The results showed that ponicidin could undergo general metabolic reactions, such as oxidation, reduction, hydrolysis, methylation and glucuronidation. Furthermore, there was an obvious difference in the ponicidin metabolites among four species in vitro. This is the first time that the SWATH™ data acquisition mode has been used to characterize ponicidin metabolites in trace amounts or in a biological matrix. These results not only provided a better understanding of the safety and efficacy of ponicidin but also showed a valuable methodology for the identification of other ent-kaurane diterpenoid metabolites.

Knowledge of nutrient storage and partitioning in forests is imperative for ecosystem models and ecological theory. Whether the nutrients (N, P, K, Ca, and Mg) stored in forest biomass and their partitioning patterns vary systematically across climatic gradients remains unknown. Here, we explored the global-scale patterns of nutrient density and partitioning using a newly compiled dataset including 372 forest stands. We found that temperature and precipitation were key factors driving the nutrients stored in living biomass of forests at global scale. The N, K, and Mg stored in living biomass tended to be greater in increasingly warm climates. The mean biomass N density was 577.0, 530.4, 513.2, and 336.7 kg/ha for tropical, subtropical, temperate, and boreal forests, respectively. Around 76% of the variation in biomass N density could be accounted by the empirical model combining biomass density, phylogeny (i.e., angiosperm, gymnosperm), and the interaction of mean annual temperature and precipitation. Climate, stand age, and biomass density significantly affected nutrients partitioning at forest community level. The fractional distribution of nutrients to roots decreased significantly with temperature, suggesting that forests in cold climates allocate greater nutrients to roots. Gymnosperm forests tended to allocate more nutrients to leaves as compared with angiosperm forests, whereas the angiosperm forests distributed more nutrients in stems. The nutrient-based Root:Shoot ratios (R:S), averaged 0.30 for R:SN , 0.36 for R:SP , 0.32 for R:SK , 0.27 for R:SCa , and 0.35 for R:SMg , respectively. The scaling exponents of the relationships describing root nutrients as a function of shoot nutrients were more than 1.0, suggesting that as nutrient allocated to shoot increases, nutrient allocated to roots increases faster than linearly with nutrient in shoot. Soil type significantly affected the total N, P, K, Ca, and Mg stored in living biomass of forests, and the Acrisols group displayed the lowest P, K, Ca, and Mg.

China has been implementing the world's most ambitious afforestation and forest conservation programs and undergoing rapid forest expansion since 1990s, thus, understanding the forest dynamics in China has global implications for sustainable forest management. Through analyzing forest area, biomass dynamics, and factors influencing deforestation and forest restoration, we found that the natural disasters and economic development drove forest dynamics and transition in China. The growth of the economy and population drove up demand for forest products, facilitating deforestation. The booming economy also boosted government's investment in forest restoration and conservation programs. Natural disasters damaged and frequently destroyed forests, but they also served as stimuli for the authorities to adopt remedy forestry policies and programs that ultimately led to forest increase. Nationwide, increasing peaks of annual afforestation were observed in the late 1950s, early 1980s, and early 2000s, and the newly increased area closed for forest restoration reached the peak in 1998. All these peaks were closely associated with peaks of natural disasters (i.e., floods, drought, and dust storm events). Based on the dynamics of forest area, biomass and forest consumption over the past 40 years, forest transition occurred during the late 1980s to the early 1990s, and it also strengthened the carbon (C) sink function of forests in China (with an increasing rate of 0.137 Pg C yr.−1 during 1994–2008). Overall, our study highlighted the influences of natural disasters and economic development on the forestry policies and forest C dynamics in the newly industrialized country.

Examinations of upper elevational distribution limits of tree species can provide indications of how subalpine vegetation responds to the ongoing climate warming. Dynamics and functional mechanisms of elevational treelines are reasonably well understood, while explanations for tree species-specific upper elevational distribution limits below the treeline still remain unclear. In this study, we used a state-of-the-art dendroecological approach to reconstruct long-term changes of species-specific upper elevational distribution limits of different plant functional type (i.e., light-demanding deciduous coniferous larch at treeline, shade-tolerant evergreen coniferous fir and shade-intolerant deciduous broad-leaved birch below treeline) along elevational gradients in the Qinling Mountains of north-central China. Over the past three centuries, all the upper species limits shifted upslope as a response to climate warming. However, the warming-induced upslope migrations showed substantial differences, displaying the maximum upward shift of larch with an average elevation of 24.7 m during the past century, while only a slight advance of the non-treeline tree species. The disparity in elevational advance of upper species limits might be attributable to the presence of interspecific competition, showing that the non-treeline tree species experienced intermediate interspecific competition while the treeline tree species experienced no interspecific competition. Thus, our findings suggested that in addition to climate warming, biotic interaction may contribute much to shaping the species-specific upper limit dynamics. This study not only enhanced mechanistic understanding of long-term species-specific upper elevational distribution limit changes, but also highlighted the jointly effects of rising temperatures and species interactions on subalpine vegetation dynamics.

Biopharmaceutical technology is one of the most promising biotechnologies in the world. With the development of modern biotechnology, biopharmaceuticals are thriving and developing rapidly in the world as a high-tech biotechnology industry, bringing unprecedented market prospects to biopharmaceuticals in China and the world. Chinese biopharmaceutical industry is booming and growing up. The national biopharmaceutical industry of China, especially the development and industrialization with genetic engineering drugs as its core fields, has already reached a certain market scale after nearly 20 years of development. The biopharmaceutical industry will be one of the most active economic sectors in China, whereas the biotechnological revolution with modern biopharmaceutical technology has become the lifeblood of maintaining human health and food safety in the future. The article explores the current status, trend, existing problems and development strategies of the biopharmaceutical industry and industrial bases in China.