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Human activities have released a large amount of nitric oxides (NOx) into the atmosphere, leading to elevated regional atmospheric NOx concentration and nitrogen (N) deposition. Several studies have observed a downward NOx or NOy (NOx and its oxidation products) flux to the forest canopy, but attributed it to the photochemical reactions and conversion from gaseous N to particulate N. Here, we focus on the possibility of NOx sink by forest canopy based on an observed downward NOx flux of 0.28 kg N ha−1 yr−1 in a temperate forest of northeastern China, using hourly monitoring of NOx fluxes. In combination with results from previous studies, we find that the downward NOx or NOy fluxes ranged from 0.2 to 1.4 kg N ha−1 yr−1 in temperate forests and from 5.3 to 8.5 kg N ha−1 yr−1 in subtropical forests and they were positively related to atmospheric NOx concentration, mean annual air temperature and annual precipitation across eight forest sites from around the world. If assuming 50% of downward NOx or NOy was directly taken up by the canopy, we estimate a NOx or NOy sink of 0.2 and 1.1 Tg N yr−1 by global respective temperate and subtropical forests, representing an effective scavenger of atmospheric NOx and a considerable N source to forests. We suggest that interception of NOx or NOy by forest canopy should be considered in global NOx budgets and their contribution to the global forest N pool in global Earth System's models. Plain Language Summary: Canopy interception of reactive N has gained wide attention in recent several years, however, its quantification is still unclear. In the present work, we demonstrate the NOx downward movement in a typical temperate forest in northeastern China was partially driven by canopy biological uptake, and then combined results of our in situ observation of canopy NOx flux with other existing 10 monitoring sites worldwide. We estimated an N input of 0.2 and 1.1 Tg N yr−1 in global respective temperate and subtropical forests via downward NOx movement, representing an effective scavenger of atmospheric NOx and a considerable N source to forests. Key Points: The potential importance of canopy NOx uptake by forests for atmospheric NOx concentration and forest N pools is unclearCombining present and previous study results, we estimated a canopy N input of 0.2–1.1 Tg yr−1 in global temperate and subtropical forestsWe suggest that interception of NOx by forest canopy should be considered in global NOx budgets and forest N pools [ABSTRACT FROM AUTHOR]

Forests worldwide store large quantities of carbon (C), particularly in soils as soil organic C (SOC). In northeastern China, two dominant forest types, secondary mixed forest (MF) and larch plantation forest (LF), cover extensive areas. However, we lack an understanding of the patterns and the mechanisms of SOC storage and stabilization in MF and LF, especially in deep soil layers. This research aims to illustrate the vertical distribution and mineral protection of SOC over soil depth; we also used δ13C values of soil fractions to evaluate SOC stability. Samples from the surface litter (Oi), organic layer (Oa+e), and 0–40 cm mineral soils were collected from both MF and LF plots. We used two different methods to separate bulk soils into distinguished fractions: (1) macro- and micro-aggregates and the non-aggregated fraction, and (2) particulate organic matter (POM) and mineral-associated organic matter (MAOM). The C concentrations, C stocks, and δ13C of all soil fractions were determined. Our findings were as follows: (1) SOC was mainly stored in mineral soils and was 13.6% lower in LF (8609 ± 1180 g C m−2) than MF (9969 ± 2084 g C m−2). (2) In both MF and LF, the SOC stock was mainly stored in aggregates (averaged 92.7%); macroaggregates dominated in the surface layers (Oa+e layer and 0–10 cm) but microaggregates dominated in the deep layers (10–20 cm and 20–40 cm). In mineral soils, MAOM was the dominant fraction of the C stock (averaged 81.6%). (3) The proportion of C distributed in microaggregates and MAOM increased from Oa+e to the 20–40 cm layer. (4) The C/N ratios and δ13C values of MAOM were smaller and heavier compared to those of POM. Our study demonstrated that in both forests, aggregate formation and mineral association predominantly contributed to SOC storage, and large stocks of SOC were distributed in the deep soil. The increasing proportion of SOC in microaggregates and MAOM along the soil depth, most likely derived from microbial turnover and microbial necromass, influenced SOC stability in both forest types. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Increasing atmospheric nitrogen (N) deposition represents a major global change factor, but its long‐term effect on tree growth and carbon (C) sequestration remains uncertain. Our manipulation experiment and meta‐analysis reveal that N deposition in temperate and boreal forests promoted tree growth and the allocation of more C into wood than into leaves in China and worldwide. Thus, N deposition may increase forest C sequestration through enhanced wood production and distribution of C into stable sinks. In the context of achieving "Carbon Neutrality," understanding how N deposition affect long‐term forest C sinks will help us with mitigation strategies under climate change. Summary: Increased nitrogen (N) deposition is driving many temperate and boreal forests in the Northern Hemisphere towards N saturation. However, it is uncertain how long‐term N deposition affects tree growth and carbon (C) allocation in these forests.To investigate this, we treated temperate larch and mixed forests in northeastern China with N additions for 8 years. In addition, we collected data from 25 N‐addition experiments in temperate and boreal forests worldwide to reveal the overall effects of N on tree growth and C allocation.Nitrogen additions significantly promoted total biomass increment by 24% in both study forests, with on average additional 8 kg C per kg N gain into woody biomass over the study period. Nitrogen additions increased the ratio of woody biomass increment to foliage litterfall production in the larch forest (by 34%). Literature data analysis also revealed greater N promotion on wood (24%) over foliage (9%) production. However, the positive effect on foliage diminished over time.These results combined imply that N deposition may promote tree growth in temperate and boreal regions and drive proportionally more photosynthate allocation into wood than leaves, thus may enhance forest C sequestration in the long run. [ABSTRACT FROM AUTHOR]

Real-time semantic segmentation is a challenging task as both segmentation accuracy and inference speed need to be considered at the same time. In this paper, a Dual Context Network (DCNet) is presented to address this challenge. It contains two independent sub-networks: Region Context Network and Pixel Context Network. Region Context Network is main network with low-resolution input and features re-weighting module to achieve sufficient receptive field. Meanwhile, Pixel Context Network with location attention module is to capture the location dependencies of each pixel for assisting the main network to recover spatial detail. A contextual feature fusion is introduced to combine output features of these two sub-networks. The experiments show that DCNet can achieve high-quality segmentation while keeping a high speed. Specifically, for Cityscapes test dataset, it can achieve 76.1% Mean IOU with the speed of 82 FPS on a single GTX 2080Ti GPU when using ResNet50 as backbone and 71.2% Mean IOU with the speed of 142 FPS when using ResNet18 as backbone. [ABSTRACT FROM AUTHOR]

Greenwashing is an obstacle to the sustainable development of society, but the current governance of greenwashing is still a "common" governance, not a "collaborative" governance. Accordingly, this study focuses on the three stakeholders of greenwashing governance: company, media and government. Using a sample of listed companies that have published social responsibility reports from 2014 to 2018, this study analyzes the influence mechanism of media reports on greenwashing and discusses the moderating role of government regulation and mediating role of internal supervision. This study finds that internal supervision plays a hiding role in the process of media reports reducing greenwashing, but government regulation has a weakening effect on this hiding effect, showing a "common" governance. Simultaneously, this "common" governance is heterogeneous across time (i.e., corporate life cycle), space (i.e., spatial spillovers) and environment (i.e., the uncertainty of corporate external policies). However, when the cooperation between the government and the media is strengthened, the hiding behavior of the companies is suppressed and the performance of greenwashing governance is improved, so that "collaborative" governance is achieved. Against this backdrop, this study provides a macro‐to‐micro governance policy framework for corporate greenwashing from the four dimensions of strategy, systems, tools, and information to achieve "collaborative" governance. This study enriches the research on the corporate greenwashing governance and has practical implications for the government, media and other stakeholders. [ABSTRACT FROM AUTHOR]

Conversion of natural and secondary mixed forests to plantation monocultures can alter soil physical, chemical, and biological properties, which may lead to changes in ecosystem nitrogen (N) status by altering soil N availability. However, assessing and comparing N status between forest types within and across sites remain challenging because different indicators often yield contradicting conclusions. We developed a multiple‐indicator approach to evaluate N status across sites and between larch monocultures and mixed secondary forests paired at three sites (Daxinganling, Maoershan, and Qingyuan) in northeastern China. The selected indicators were foliar N content (%N), soil carbon‐to‐N ratio (C/N), soil inorganic N, foliar 15N natural abundance (δ15N), and δ15N of bulk soil, ammonium, and nitrate in the soil profiles. Our results, as shown mainly by C/N of soil organic layer and the fraction of nitrate in soil inorganic N, showed that N availability increased from north to south in the order Daxinganling < Maoershan < Qingyuan, along with the increasing climatic (mean annual temperature and mean annual precipitation) and N deposition gradients. We also found that the mixed forests had lower N availability than the larch plantations at the two north sites (Daxinganling and Maoershan), while the opposite was found in the south site (Qingyuan). The site‐specific pattern of N availability in the larch versus mixed stands reflects the difference in their succession and management histories. Our study demonstrated that a multiple‐indicator approach is needed for a comprehensive comparison of the N status of different forest types both within and across sites. [ABSTRACT FROM AUTHOR]

Environmental change factors can significantly affect the composition and physiology of soil microbes. How the resulting changes in the community composition are related to microbial functions, however, remains poorly understood. We investigated the effects of climate warming (+ 1.4°C of air temperature and + 0.75°C of soil temperature at 10 cm depth) and reactive nitrogen (N) input (12 g N m–2 year–1) on the community composition and physiologies of soil bacteria in a semiarid Loess grassland. Soil bacterial communities were assessed by Miseq sequencing of 16S rRNA gene amplicons while their physiological properties were assessed by microbial metabolic quotients (qCO2, microbial respiration per unit of microbial biomass) and microbial community-level physiological profiles (CLPPs). Our results showed that N input, but not warming, altered bacterial community structure, although both warming and N input significantly affected the abundances of certain phyla. While phyla Verrucomicrobia and Chloroflexi were sensitive to warming, Saccharibacteria, Bacteroidetes and Actinobacteria were primarily responsive to N input. Both warming and N input increased microbial metabolic quotients, but only warming significantly impacted soil microbial CLPPs with L-cysteine, oxalic acid, oxoglutaric acid and aminobutyric acid being the sensitive C sources. Structural equation modeling showed that warming and N input influenced soil bacterial phyla through soil moisture, soil NO3––N and plant biomass. The sensitive bacterial phyla, not the whole community property, were significantly correlated with qCO2 and microbial C utilization. Our findings suggest that responses of bacterial groups sensitive to environmental change factors, rather than the whole community, may exert dominant effects on soil microbial functions under future climate change scenarios. [ABSTRACT FROM AUTHOR]

Emissions of dinitrogen (N2) and nitrous oxide (N2O) from soil are important components of the global nitrogen cycle. Soil N2O emissions from terrestrial ecosystems have been well studied. However, patterns and mechanisms of N2 emissions remain unclear due to the technical difficulty in measuring N2 production. In this study, an in situ 15N labeling method was employed to determine soil N2 and N2O emission rates from the lower, middle, and upper slopes, which correspond to different moisture conditions, in a temperate forest in Northeast China. We found that N2 emissions varied from 85 to 3442 μg N m−2 h−1 across the slopes and were dominated by denitrification. The emissions of bulk N2O (22 to 258 μg N m−2 h−1) and denitrification-derived N2O (14 to 246 μg N m−2 h−1) were significantly lower than N2 emissions from their corresponding slope positions. Both N2 and N2O emissions significantly increased when soils become wetter. The ratios of N2O/(N2O + N2) were significantly higher at the upper and middle slopes (0.22 and 0.20, respectively) compared with those at the lower slope (0.08 ± 0.01). At the catchment scale, N2 accounted for 85% of the total gaseous N losses (N2O + N2). Our study shows that soil moisture drives the patterns of N2 and N2O emissions and field quantification of N2O/(N2O + N2) ratio should further consider the effect of slope position of forest ecosystems to estimate total soil gaseous N losses. [ABSTRACT FROM AUTHOR]

This study aimed to prepare effervescent tablets of traditional Chinese medicine Xianganfang with fresh juice using a semi-solid 3D printer with three cartridge holders to seperate acid and alkali source by drug paste through model design to avoid sticking impact and premature effervescence during the tableting in the conventional preparation process. The powder of Xianganfang including fresh juice of Phyllanthus emblica and licorice extract was obtained by vacuum freeze-drying with 50% mannitol as cryoprotectant. Then, the formulation of 3D-printed effervescent tablets was investigated. Further 5% HPMC hydroalcoholic gel was mixed with sodium bicarbonate and freeze-dried Xianganfang powder to prepare alkali source and drug paste respectively while 30% PVP ethanol solution was mixed with tartaric acid to prepare acid source paste; these three pastes had good printability. The pastes of drug, acid, and alkali were loaded into three syringe cartridges separately and numbered as "3," "5," and "7," according to cartridge holders of the 3D printer, and printed in the order of "537,353,735" for separating acid and alkali by drug to avoid premature effervescence. And the basic printing parameters were optimized. The tablets were evaluated by the appearance, tablet weight variation, hardness, disintegration time, friability, pH, and stability. The physicochemical properties all conformed to the Chinese Pharmacopoeia 2020 edition. The content of the active ingredient gallic acid was 0.769 ± 0.019 mg/g. This study provided a new method to prepare effervescent tablets of traditional Chinese medicine with fresh juice using 3D printing technology. [ABSTRACT FROM AUTHOR]

Background: Forest succession is an important ecological process and has been studied for more than a century. However, changes in nitrogen (N) availability during succession remain unclear as they may lead to either N saturation or N limitation. Here, we propose a conceptual model to illustrate changes in N availability during four stages of secondary succession using the natural abundance of 15N in plant leaves (foliar δ15N). We predicted that N availability would decline in the early stages of succession and then increase in late stages, coinciding with the changes in foliar δ15N, with the inflection point varying in different climate zones. Data on foliar δ15N from 16 succession sequences were synthesized to explore changes in N availability during forest succession. Results: The compiled data were consistent with the proposed conceptual model. Foliar δ15N in boreal and temperate forests decreased significantly in the first two stages of succession (estimated to last at least 66 years in temperate forests), at a rate of 0.18‰ and 0.38‰ per decade, respectively, and decreased slightly in tropical forests in the first 23 years. Foliar δ15N is projected to increase in later stages in all forests, which is supported by observations in both temperate and tropical forests. The inflection points of N availability when N limitation peaked during succession were different in different climate zones, implying different ecosystem N turnovers. Conclusions: Our study reconciles the controversies regarding changes in N availability during forest secondary succession. Our findings are also useful for predicting the recovery of N and carbon accumulation during succession. Nonetheless, studies on forest secondary succession using foliar δ15N have thus far been limited, and more research should be conducted to further verify the conceptual model proposed here. [ABSTRACT FROM AUTHOR]

Assessment of nitrogen (N) saturation of forests is critical to the evaluation of the manner in which ecosystems will respond to current and future global changes such as N deposition. However, quantifying N saturation remains a challenge. We developed a conceptual model of N saturation stages in forest ecosystems based on (1) a hypothetical relative rate of ammonification, nitrification, and denitrification, (2) concentrations of ammonium and nitrate in the soil, and (3) 15N enrichment pattern of bulk soil N, ammonium, and nitrate in the soil profile. We tested the hypotheses using data from forests located at five sites across eastern Asia. The fraction of nitrate in total inorganic N indicated that the sites represent an N saturation gradient with one boreal forest at stage 1 (least saturated), three temperate forests at stage 2, and one tropical forest at stage 3 (most saturated). The δ15N of bulk soil N increased from topsoil to subsoil more sharply at N‐limited sites than at the N‐rich sites along the N deposition gradient. We also found distinct 15N enrichment patterns of bulk soil N, ammonium, and nitrate in the soil profile across the study sites. At stage 1, nitrate was more 15N‐depleted than ammonium only in the organic soil horizon, indicating limited nitrification, while the 15N depletion of nitrate to ammonium was observed in the deeper mineral soil at stages 2 and 3. Furthermore, ammonium was more 15N‐depleted than bulk soil N at stages 1 and 2 but more 15N‐enriched than bulk soil N at stage 3. Our study suggests that soil profile patterns of δ15N of bulk soil N, ammonium, and nitrate provide information about the relative rates of mineralization, nitrification, and denitrification and thus can be an additional measure of N saturation of forest ecosystems across broad environmental gradients. [ABSTRACT FROM AUTHOR]

The impacts of enhanced nitrogen (N) deposition on the global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and their contributions to forest C sinks are unclear. Here, we analyze results from 13 ecosystem-scale paired 15N-labelling experiments in temperate, subtropical, and tropical forests. Results show that total ecosystem N retention is similar for ammonium and nitrate, but plants take up more labelled nitrate ( 20 15 25 %) ( mean minimum maximum ) than ammonium ( 12 8 16 %) while soils retain more ammonium ( 57 49 65 %) than nitrate ( 46 32 59 %). We estimate that the N deposition-induced C sink in forests in the 2010s is 0.72 0.49 0.96 Pg C yr−1, higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition. A study using paired 15N tracers shows atmospheric N deposited in oxidized form is more likely retained by trees, while the reduced form is retained in soil. The authors argue that this is a greater contribution of deposited N to the global forest C sink than previously reported. [ABSTRACT FROM AUTHOR]

Resource integration of coal enterprises is conducive to reducing pollution and carbon emissions, thus alleviating environmental problems such as global warming. Government regulation has a great influence on enterprise behavior. Therefore, it is necessary to analyze the strategies of government and coal enterprises in resource integration. Based on the perspective of government regulation, this paper discusses how to guide and restrict coal enterprises to conduct resource integration behavior, and whether the government supervises this behavior. First, through empirical research, government regulations of coal enterprises are given practical policy implications. Second, using evolutionary game and simulation technology, from the perspective of government regulation, we explore the complex behavioral interaction mechanism between the dominant and inferior coal enterprises, the mechanism between the government and coal enterprises, and analyze the impact of key factors on the dynamic evolution process. Finally, the sensitivity analysis of the selected parameters is discussed in details, which provides useful decision-making suggestions for the government and enterprises. In addition, this paper further analyzes the impact of different government policies on coal enterprises' green innovation strategies. Results demonstrate that (1) when the power gap between enterprises is large, the probability of dominant enterprises choosing resource integration converges to 1, while the probability of inferior enterprises converges to 0. Therefore, government regulations are invalid for inferior enterprises; (2) the combination of government regulations can help improve the efficiency of coal enterprises' strategic choices. With the increase in the intensity of government rewards and punishments, the probability of enterprise resource integration evolves from 0 to 1; (3) excessive government regulations make the choice between the government and coal companies tend to swing, because the probability of the two is between 0 and 1. Therefore, excessive government regulations cannot effectively achieve resource integration and government regulation. (4) The government subsidy strategy is less effective than the government's pollution penalty strategy in promoting the green innovation of enterprises. Our research shows that the government should choose different policy combinations and intensities to regulate resource integration according to the market power of coal enterprises, which provides theoretical reference and practical guidance for the government to regulate corporate resource integration behavior. [ABSTRACT FROM AUTHOR]

The effects of nitrogen (N) deposition on forests largely depend on its fate after entering the ecosystem. While several studies have addressed the forest fate of N deposition using 15N tracers, the long‐term fate and redistribution of deposited N in tropical forests remains unknown. Here, we applied 15N tracers to examine the fates of deposited ammonium (NH4+) and nitrate (NO3‐) separately over 3 years in a primary and a secondary tropical montane forest in southern China. Three months after 15N tracer addition, over 60% of 15N was retained in the forests studied. Total ecosystem retention did not change over the study period, but between 3 months and 3 years following deposition 15N recovery in plants increased from 10% to 19% and 13% to 22% in the primary and secondary forests, respectively, while 15N recovery in the organic soil declined from 16% to 2% and 9% to 2%. Mineral soil retained 50% and 35% of 15N in the primary and secondary forests, with retention being stable over time. The total ecosystem retention of the two N forms did not differ significantly, but plants retained more 15NO3‐ than 15NH4+ and the organic soil more 15NH4+ than NO3‐. Mineral soil did not differ in 15NH4+ and 15NO3‐ retention. Compared to temperate forests, proportionally more 15N was distributed to mineral soil and plants in these tropical forests. Overall, our results suggest that atmospherically deposited NH4+ and NO3‐ is rapidly lost in the short term (months) but thereafter securely retained within the ecosystem, with retained N becoming redistributed to plants and mineral soil from the organic soil. This long‐term N retention may benefit tropical montane forest growth and enhance ecosystem carbon sequestration. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori) infection has become an international public health problem, and antibiotic-based triple or quadruple therapy is currently the mainstay of treatment. However, the effectiveness of these therapies decreases due to resistance to multiple commonly used antibiotics. Sanguisorba officinalis L. (S. officinalis), a traditional Chinese medicine clinically used for hemostasis and treatment of diarrhea, has various pharmacological activities. In this study, in vitro antimicrobial activity was used for the preliminary evaluation of S. officinalis against H. pylori. And a pharmacology analysis approach was also utilized to elucidate its underlying mechanisms against H. pylori infection. Methods: Micro-broth dilution method, agar dilution method, checkerboard assay, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used for the assessment of anti-bacterial activity. Active ingredients screening, GO analysis, KEGG analysis, construction of PPI network, molecular docking, and RT-qPCR were used to elucidate the underlying pharmacological mechanisms of S. officinalis against H. pylori infection. Results: The minimum inhibitory concentration (MIC) values of S. officinalis against multiple H. pylori strains including clinically isolated multi-drug resistant (MDR) strains were ranging from 160 to 320 µg/ml. These results showed that S. officinalis had additive interaction with four commonly used antibiotics and could exert antibacterial effect by changing the morphology of bacteria without developing drug resistance. Through network pharmacology analysis, 8 active ingredients in S. officinalis were screened out for subsequent studies. Among 222 putative targets of S. officinalis, 49 targets were identified as potential targets for treatment of H. pylori infection. And these 49 targets were significantly enriched in GO processes such as protein kinase B signaling, protein kinase activity, protein kinase binding, and KEGG pathways such as Pathways in cancer, MicroRNAs in cancer, and TNF signaling pathway. Protein-protein interaction analysis yielded 5 core targets (AKT1, VEGFA, EGFR, SRC, CCND1), which were validated by molecular docking and RT-qPCR. Conclusions: Overall, this study confirmed the in vitro inhibitory activity of S. officinalis against H. pylori and explored the possible pharmacological mechanisms, laying the foundation for further research and clinical application. [ABSTRACT FROM AUTHOR]

Summary: Conifers are considered to prefer to take up ammonium (NH4+) over nitrate (NO3−). However, this conclusion is mainly based on hydroponic experiments that separate roots from soils. It remains unclear to what extent mature conifers can use nitrate compared to ammonium under field conditions where both roots and soil microbes compete for nitrogen (N).We conducted an in situ whole mature tree nitrogen‐15 (15N) labeling experiment (15NH4+ vs 15NO3−) over 15 d to quantify ammonium and nitrate uptake and assimilation rates in four 40‐yr‐old monoculture coniferous plantations (Pinus koraiensis, Pinus sylvestris, Picea koraiensis and Larix olgensis, respectively).For the whole tree, 15NO3− contributed 39% to 90% to total 15N tracer uptake among four plantations during the study period. At day 3, the 15NO3− accounted for 77%, 64%, 62% and 59% by Larix olgensis, Pinus koraiensis, Pinus sylvestris and Picea koraiensis, respectively.Our study indicates that mature coniferous trees assimilated nitrate as efficiently as ammonium from soils even at low soil nitrate concentration, in contrast to the results from hydroponic experiments showing that ammonium uptake dominated over nitrate. This implies that mature conifers can adapt to increasing availability of nitrate in soil, for example, under the context of globalization of N deposition and global warming. [ABSTRACT FROM AUTHOR]

To solve the problem of the autonomous collaboration of unmanned cluster under control rule failure, a cooperative evolution mechanism of unmanned cluster based on multi-player public goods evolutionary game is proposed. It starts with the requirement analysis of cooperative evolution in the unmanned cluster. And, the evolutionary game model of the multi-player public goods based on the aspiration driven rule is established. Then the average abundance function is constructed by theoretical derivation. Furthermore, the influence of cost, multiplication factor and aspiration level on the average abundance is simulated. Finally, the mechanism of the parameter change on the evolutionary cluster cooperation behavior is revealed via case study, and the rationalization proposals are suggested to provide a meaningful exploration for the transformation from theory to application. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) form symbiosis with most terrestrial plant roots, obtaining photosynthates in return for mineral nutrients. Ecological theories based on the economics of trading partnership predict that nutrient enrichment would suppress AMF. Experimental results from nitrogen (N) and phosphorus (P) additions, however, were highly variable, and the underlying mechanisms remain unclear. Here we show distinct AMF responses to soil N:P stoichiometry manipulations via gradients of long‐term N and P additions in a Mongolian steppe. A complementary experiment with an acid addition gradient was designed to help tease apart the effect of N‐induced acidification from N nutrient. AMF root colonization and extraradical fungal biomass progressively decreased along the P gradient under two distinct host plant species, suggesting a carbon (C)‐P tradeoff. In contrast, low to moderate N inputs increased both AMF parameters, corresponding to the increasing N:P ratio. Yet, high N inputs reduced AMF colonization and biomass, and the magnitudes of N‐led inhibition were similar to those under acid additions that induced comparable changes in soil pH. Structural equation modeling further showed that while soil N:P stoichiometry primarily controlled the effect of P addition on AMF, N‐induced soil acidity overtook the N:P stoichiometry under high N inputs and dominated the effects of reactive N on AMF. In addition, AMF community composition in roots was more dependent on host plants and unresponsive to changes in soil nutrients. We further proposed a comprehensive framework that integrates biological and geochemical effects of reactive N and P inputs on AMF. Together, these results indicate that while the C‐P tradeoff controls P suppression of AMF, N‐induced acidification dominates the N inhibition. Our findings suggest that incorporation of geochemical impacts of N and P inputs would facilitate modeling efforts to project mycorrhizal impact on plant interactions and soil C balance under future nutrient enrichment scenarios. [ABSTRACT FROM AUTHOR]

Measuring the nitrogen isotope compositions (δ15N) of nitric oxide (NO) from different sources helps to quantify the relative contributions of atmospheric NOx. Soil is one of the most important sources of atmospheric NOx, but only limited measurements on the δ15N of soil‐emitted NO exist, hampering our ability to partition sources to air pollution. Here we conducted soil incubations to measure the δ15N‐NO under defined aerobic or anaerobic conditions, favoring either nitrification or denitrification. Soils were collected from seven sites spanning three ecosystems in northern China (two agricultural, two forest, and three grassland sites). We found that the δ15N‐NO and their associated N isotope fractionations were significantly different between anaerobic and aerobic conditions in seven soils. Under aerobic condition, the δ15N‐NO ranged from −62‰ to −50‰ (averaged −56 ± 4‰), being significantly more negative (by 23‰) than those under anaerobic condition (−45‰ to −23‰, averaged −33 ± 7‰). The apparent N isotope fractionation for NO production under aerobic condition (15εaerobic = 61 ± 3‰) was significantly higher (by 26‰) than under anaerobic condition (15εanaerobic = 35 ± 6‰), with a small variability among ecosystem types. Our study demonstrates that the δ15N‐NO from different soils are very different from fuel combustions (mainly from 0‰ to +20‰), supporting that measuring 15N is a useful tool to partition the contributions of soil NO to atmospheric NOx. Our results also imply δ15N‐NO produced by nitrification and denitrification distinctly different, as these two processes are dominant processes producing NO under aerobic and anaerobic conditions, respectively. Plain Language Summary: Nitric oxide (NO) affects the atmosphere chemistry and NO itself a key component of air pollution and a precursor to other air pollutants like particulate matter and ozone. To reduce the air pollution, it is crucial to identify the atmospheric NO sources. Measuring 15N natural abundance has been considered as a promising tool to identify different sources, but the measurement on δ15N for soil‐emitted NO is limited, adding to the large uncertainties on NO partitioning. Here we measured the δ15N‐NO emitted from three ecosystem types across seven sites (two agriculture, two forest, and three grassland sites) under defined anaerobic or aerobic conditions. We found that soil‐emitted NO was 15N‐depleted (−62‰ to −23‰) related to the source from fossil fuel combustion (0–20‰), suggesting that δ15N can be used to separate these two sources. We also found that the δ15N‐NO under aerobic condition (nitrification prevailing, −62‰ to −50‰) was much lower than under anaerobic condition (denitrification prevailing, −45‰ to −23‰), which provide a useful tool to better understand the relative contributions of different sources of NO. In sum, soil‐emitted NO has their own different isotope fingerprint, depending on the soil oxygen conditions, and can be used to partition sources. Key Points: The δ15N‐NO from soil (−62‰ to −23‰) is different from fuel combustion (0‰ to 20‰), allowing effective source partitionThe δ15N‐NO produced under aerobic condition (favor nitrification) was more negative than under anaerobic condition (favor denitrification)The 15ε for NO production under aerobic condition (61 ± 3‰) was significantly higher than under anaerobic condition (35 ± 6‰) [ABSTRACT FROM AUTHOR]

To explore the feasibility of preparing traditional Chinese medicine using 3 D printing technology and reduce warpage commonly occurs in large-size tablets, we investigated the prescription, warpage optimization and influence factors of 3 D printing Jiuxiang Jianpi Yangwei (JJY) tablets. The procedures used conformed to the requirements of the 2015 edition of the Chinese Pharmacopeia. The results of the prescription screening showed that 75% ethanol and HPMC (9%) could be adhesives. Meanwhile, stevia (0.5%) and citric acid (0.5%) improved the taste of the 3 D printed JJY tablets. To ensure the quality and appearance of the printed tablets, the best parameters were as follows: drying at room temperature, 40% of the filling density, a 3 mm model height, two outer ring numbers and a printing speed of 15 mm/s. The optimized printed tablets had a smooth appearance, suitable hardness, with the weight uniformity in accordance with the Pharmacopeia. We also prepared personalized JJY cartoon tablets (which contained images of a big-headed pig and a small yellow duck) which were designed to increase the compliance of children when taking their medications. In conclusion, this study reported that 3 D printing technology has great potential for preparing traditional Chinese medicines, and it provided guidance for 3 D printing tablets without warpage. [ABSTRACT FROM AUTHOR]

Urbanization negatively impacts the diversity of aquatic insect assemblages in headwater streams and can lead to the homogenization of insect communities at the regional level. However, less is known about the impact of urbanization on insects in headwater streams within smaller cities that have significant upstream portions outside of urban land use. We collected insects monthly from April to September in 2014 and 2015 from five streams that flowed from rural upstream through urban downstream land use, plus two rural reference streams, in Greater Binghamton, New York, in the northeast USA. While urbanization was associated with lower insect taxonomic richness ( α ¯ ) and elevated stream water conductivity, the regional diversity (γ) was similar among urban and rural land use. This corresponded to higher dissimilarity among urban sites (β) than among rural sites. To our knowledge, this is the first report of higher urban stream insect community β-diversity. Our results suggest that urbanization in this medium-sized city negatively impacts stream insect richness, but the change of community assemblages is not homogenous across the urban landscape. Connectivity between upstream rural sites and downstream urban sites may provide some relief from the impacts of urbanization in smaller cities. [ABSTRACT FROM AUTHOR]

Quantifying soil organic carbon (SOC) changes is a fundamental issue in ecology and sustainable agriculture. However, the algorithm‐derived biases in comparing SOC status have not been fully addressed. Although the methods based on equivalent soil mass (ESM) and mineral‐matter mass (EMMM) reduced biases of the conventional methods based on equivalent soil volume (ESV), they face challenges in ensuring both data comparability and accuracy of SOC estimation due to unequal basis for comparison and using unconserved reference systems. We introduce the basal mineral‐matter reference systems (soils at time zero with natural porosity but no organic matter) and develop an approach based on equivalent mineral‐matter volume (EMMV). To show the temporal bias, SOC change rates were recalculated with the ESV method and modified methods that referenced to soils at time t1 (ESM, EMMM, and EMMV‐t1) or referenced to soils at time zero (EMMV‐t0) using two datasets with contrasting SOC status. To show the spatial bias, the ESV‐ and EMMV‐t0‐derived SOC stocks were compared using datasets from six sites across biomes. We found that, in the relatively C‐rich forests, SOC accumulation rates derived from the modified methods that referenced to t1 soils and from the EMMV‐t0 method were 5.7%–13.6% and 20.6% higher than that calculated by the ESV method, respectively. Nevertheless, in the C‐poor lands, no significant algorithmic biases of SOC estimation were observed. Finally, both the SOC stock discrepancies (ESV vs. EMMV‐t0) and the proportions of this unaccounted SOC were large and site‐dependent. These results suggest that although the modified methods that referenced to t1 soils could reduce the biases derived from soil volume changes, they may not properly quantify SOC changes due to using unconserved reference systems. The EMMV‐t0 method provides an approach to address the two problems and is potentially useful since it enables SOC comparability and integrating SOC datasets. [ABSTRACT FROM AUTHOR]

Aquatic insects play a large role in the processing of organic matter in headwater streams; however, anthropogenic disturbances associated with watershed urbanization can impact the biodiversity and abundance of these insects. Aquatic insects function on multiple trophic levels (i.e., shredders, collectors, scrapers, and predators) and interact in the nutrient cycling within lotic systems. The degradation or loss of any of these functional groups could disrupt stream biogeochemistry and the flow of energy in stream ecosystems. We used a paired reach site design to assess the insect functional group representation in five streams impacted by urbanization with downstream urban and upstream rural reach sites. We also sampled two non‐urban reference streams with rural upstream and rural downstream reach sites. We assessed functional group richness and abundance and measured insect biomass, insect body nitrogen (N) content, phosphorus (P) content, and N:P ratio. We found that collectors were numerically the most abundant and taxonomically the richest insect group in all site types. There were much fewer insects collected from urban sites than rural sites and individual insects were generally smaller in the urban sites. Collectors represented the most insect biomass in urban sites and predators the most insect biomass in rural sites. Insect N and P concentrations were not affected by urban landuse, ranging from 88.45 ± 12.50 to 121.74 ± 15.80 mg/g and 10.60 ± 2.10 to 18.36 ± 7.05 mg/g, respectively; and N:P ratios from 3.48 to 20.97. However, lower total insect biomass, particularly of predators and shredders, led to significantly lower total N and P mass in urban sites. Urbanization had clear effects on the diversity of functional groups, insect biomass, and their nutrient mass in this medium‐sized city. [ABSTRACT FROM AUTHOR]

The glycoside hydrolase family 18 chitinases degrade or alter chitin. Multiple catalytic domains in a glycoside hydrolase family 18 chitinase function synergistically during chitin degradation. Here, an insect group III chitinase from the agricultural pest Ostrinia furnacalis (OfChtIII) is revealed to be an arthropod‐conserved chitinase that contains two nonsynergistic GH18 domains according to its catalytic properties. Both GH18 domains are active towards single‐chained chitin substrates, but are inactive towards insoluble chitin substrates. The crystal structures of each unbound GH18 domain, as well as of GH18 domains complexed with hexa‐N‐acetyl‐chitohexaose or penta‐N‐acetyl‐chitopentaose, suggest that the two GH18 domains possess endo‐specific activities. Physiological data indicated that the developmental stage‐dependent gene‐expression pattern of OfChtIII was the same as that of the chitin synthase OfChsA but significantly different from that of the chitinase OfChtI, which is indispensable for cuticular chitin degradation. Additionally, immunological staining indicated that OfChtIII was co‐localized with OfChsA. Thus, OfChtIII is most likely to be involved in the chitin‐synthesis pathway. [ABSTRACT FROM AUTHOR]

Due to intensifying human disturbance, over half of the world's tropical forests are reforested or afforested secondary forests or plantations. Understanding the resilience of carbon (C) stocks in these forests, and estimating the extent to which they can provide equivalent carbon (C) sequestration and stabilization to the old growth forest they replace, is critical for the global C balance., In this study, we combined estimates of biomass C stocks with a detailed assessment of soil C pools in bare land, Eucalyptus plantation, secondary forest and natural old-growth forest after over 50 years of forest restoration in a degraded tropical region of South China. We used isotope studies, density fractionation and physical fractionation to determine the age and stability of soil C pools at different soil depths., After 52 years, the secondary forests had equivalent biomass C stocks to natural forest, whereas soil C stocks were still much higher in natural forest (97.42 t/ha) than in secondary forest (58.75 t/ha) or Eucalyptus plantation (38.99 t/ha) and lowest in bare land (19.9 t/ha). Analysis of δ13C values revealed that most of the C in the soil surface horizons in the secondary forest was new C, with a limited increase of more recalcitrant old C, and limited accumulation of C in deeper soil horizons. However, occlusion of C in microaggregates in the surface soil layer was similar across forested sites, which suggests that there is great potential for additional soil C sequestration and stabilization in the secondary forest and Eucalyptus plantation., Collectively, our results demonstrate that reforestation on degraded tropical land can restore biomass C and surface soil C stocks within a few decades, but much longer recovery times are needed to restore recalcitrant C pools and C stocks at depth. Repeated harvesting and disturbance in rotation plantations had a substantial negative impact on the recovery of soil C stocks. We suggest that current calculations of soil C in secondary tropical forests (e.g. IPCC Guidelines for National Greenhouse Gas Inventories) could overestimate soil C sequestration and stabilization levels in secondary forests and plantations., A is available for this article. [ABSTRACT FROM AUTHOR]

Geographic routing is becoming an attractive routing solution for WSNs since it offers a radical departure from traditional topology-dependent routing paradigms through use of geographic location in data delivery. However, it often suffers from the routing hole, referring to an area free of nodes in the direction closer to destination, in various real-world environments such as buildings and obstacles, leading to route failure. Currently, most geographic routing protocols tend to exploit face routing to recover the route. The basic idea behind it is to planarize the whole network by eliminating the crossing links before applying routing algorithms, thus achieving suboptimal network performance. In this article, we first survey representative face-based geographic routing approaches, including their design prerequisites and philosophy. Furthermore, we outline the emerging issues to be addressed in the future and illustrate the forming factors behind them in detail. Based on these observations, we then propose a CAGR to address the routing hole problem by employing relative coordinate systems, avoiding planarizing networks and preserving route optimality properties. Simulation results show that the proposed approach is superior to existing protocols in terms of packet delivery ratio, control overhead, and delivery delay in WSNs over a variety of communication sessions passing through the routing holes. [ABSTRACT FROM PUBLISHER]

Urban wetlands can serve to reduce flooding and improve water quality, yet we know little about their plant communities. Our study aims to characterize the vegetation and soil parameters of these important ecosystems, and to compare these features to those of previously sampled natural wetlands in south-central New York. Vegetation and soil characteristics were sampled in eight urban wetlands and compared to six forested wetlands, five scrub-shrub wetlands, and seven emergent wetlands. Urban sites had significantly lower species richness and a higher percent cover of invasives, including Typha x glauca, Phalaris arundinacea, and Lythrum salicaria. However, non-invasive species were also common in urban flora, including Leersia oryzoides, Ludwigia palustris, and Sagittaria latifolia. Urban wetlands had a high percentage of obligate wetland species, and most closely resembled emergent wetlands in their vegetation composition. Soil pH and soil electrical conductivity were significantly higher in urban sites, but potential net N-mineralization rates were significantly lower. Urban wetland vegetation and soil characteristics are different than those in nearby natural wetlands, and our increased knowledge of these urban ecosystems will lead to more successful restoration and creation projects. [ABSTRACT FROM AUTHOR]

Background and aims: Forest restoration has been proposed as an effective strategy for the sequestration of atmosphere CO. Understanding the mechanisms of soil organic carbon (SOC) dynamics in afforestation is important to quantifying and enhancing carbon (C) sequestration. Methods: After 70 years afforestation with two conifer and three broadleaf tree species in monocultures in Northeast USA, we measured soil C pools as well as C fractions in these plantations and nearby pasture control. Results: Soil C stored in forest floor was increased by afforestation, especially in conifer stands. Total C stock in mineral soils was not statistically different among species, but C fractions had been altered. Compared to pasture land, afforestation decreased coarse particle organic C (cPOC) fraction, while increased recalcitrant mineral associated SOC (mSOC) fraction. Afforestation decreased the macro-aggregate C fraction in the 0-5 cm soil, but increased the micro-aggregate C fraction in the 5-15 cm soil. Conclusions: 1) Afforestation using conifers could improve the whole soil-profile carbon stock compared to broadleaves when the forest floor is included; 2) Even though the overall mineral soil C stock was not changed, afforestation could improve soil C stabilization through increasing mSOC fraction and forming more micro-aggregate C fraction in deeper soils. [ABSTRACT FROM AUTHOR]

Roadside plants have the potential to accumulate pollutants and safeguard waterways. To assess growth and pollutant accumulation of roadside plants, the willow Salix miyabeana was grown (a) in a greenhouse on soil collected at different distances from an interstate highway to test the longer-term effects of pollutant deposition as manifested in soil, and (b) in the field on reference soil placed at different distances from that highway to test the shorter-term effects of proximity to pollutant sources during a single growing season. In the first experiment, relative growth rate (RGR) increased 150 % with distance of soil collection from the roadway, from a baseline near the highway to 100 m away. Relative nitrogen and phosphorus accumulation rates were positively correlated with RGR ( P <0.0001), and total contents of zinc, strontium, copper, nickel, cadmium, and lead in new shoots were also positively correlated with RGR ( P <0.05). Thus more rapidly growing plants accumulated more N, P, and metals. Reduced growth for plants grown on soils collected near the roadway was associated with very high tissue concentrations of sodium and soil concentrations of chloride, implicating the deposition of deicing agents in this northern temperate roadside ecosystem. In contrast, S. miyabeana showed the opposite pattern on reference soil in the field, with RGR decreasing 31 % as distance from the roadside increased. The latter trend appears to have resulted from greater soil moisture and reduced shading near the highway. We suggest that reducing road salt applications will promote growth and pollutant accumulation by roadside vegetation. [ABSTRACT FROM AUTHOR]

The quantitative role of the canopy size of nurse shrubs on microenvironment and native tree establishment in degraded tropical lands has been seldom studied. In a 21-month field experiment, we aimed to test the effect of a native shrub with different canopy sizes on the early establishment of native trees as part of the effort of forest restoration in tropical China. We examined the microenvironment, and the seedling establishment and growth of two native trees: Castanopsis fissa and Syzygium hancei in both open space (OS) microsite and microsite under the canopy of the native pioneer shrub Rhodomyrtus tomentosa. Shrub microsite was further divided into large canopy (LC), and medium canopy (MC) microsite, based on the shrub leaf area indices. Results showed that relative to OS, LC had higher soil nutrient concentration and water content, and lower photosynthetic active radiation (PAR), while MC had lower PAR and higher soil exchangeable Mg, K, and Ca. Survival and growth were mostly enhanced, while water stress and photoinhibition reduced for C. fissa seedlings in MC and S. hancei seedlings in LC. It is found that the beneficial effects of the native shrub on seedling establishment and growth result mostly from the improvement in nutrient and water availabilities, the reduction in plant stress caused by harsh summer light, and the specific ecological requirements of different tree species. We suggest that different canopy sizes of native shrub R. tomentosa may be explored to target different native trees and hence promote forest restoration in degraded tropical ecosystems. [ABSTRACT FROM AUTHOR]

To further research the extracting method of the pig gait features, the paper firstly focus on the extraction of the pig gait frequency. A gait frequency extraction method was proposed based on analyzing the skeleton endpoints of depth image. Firstly, a series of processes, including skeleton extracting and pruning, were taken to the frames of depth image sequences. Secondly, a path similarity skeleton graph matching method was introduced to distinguish the fore-leg endpoints and the hind-leg endpoints from the skeleton graph. Then considering the characteristics of the depth image, a rule to distinguish the far-side endpoint and the near-side endpoint was constructed by calculating the average value of neighbor skeleton points of the endpoint. After ascertaining the skeleton endpoints of four legs, a variable was defined to represent the relative position of the far-side endpoint and the near-side endpoint, along the horizontal direction between frames in a sequence. Furthermore, the fitting sine curves were used to represent the variations of the fore-leg endpoints and the hind-leg endpoints separately. At last, the reciprocal of the fitting sine curve frequency can be calculated and the INTPART of double reciprocal was regarded as the fore-leg steps (FS) or the hind-leg steps (HS). The complete step (CS) was defined as the minimum of FS and HS. The finally gait frequency can be calculated by using the CS value to divide the duration of the sequence. To verify the proposal method, 28 depth image sequences of pig moving were acquired by using the KINECT depth camera, at the Rongxin pig farming of Danyang city in Jiangsu province, China. Another 28 sequences were achieved by mirror transforming along the horizontal direction to the native sequences. Experiments were taken for all the 56 sequences by using the proposal method. Experimental results show that the success rate of the method proposed in this paper is 82.1%, up to 92% for the situation when the pig moves continuously and the moving directions is perpendicular or nearly perpendicular to the axis of the depth camera only. Incorrect results often appear when the pig stays for a long time between steps or by non-cross steps, it needs to further adapt the proposal method. For the situation of rough variation of the pig body occurring in the sequence, the proposal method is not suited because the matching of skeleton points can not be achieved. That is the insufficient point of the proposal method. The proposal method would help to carry the further research of the abnormal gait of pig and construct the abnormal monitoring system by fusion of multi-source vision features. [ABSTRACT FROM AUTHOR]

Aims Forest disturbance from extreme weather events due to climate change could increase the contribution of fresh green leaves to the litter layer of soil and subsequently alter the composition and activity of the soil microbial properties and soil carbon cycling. The objective of this study was to compare the effect of naturally fallen litter and fresh leaves on the soil microbial community composition and their activities. Methods Fresh leaves and normal fallen litter were collected from four tree species (Pinus elliottii, Schima superba, Acacia mangium, A. auriculaeformis) in subtropical China and mixed with soil. Soil microbial community composition was determined using PLFAs, and its activity was quantified by soil respiration. During a 12-month period, the decomposition rate of litter was measured bimonthly using a litterbag method. Soil microbial samples were collected after 6 and 12 months. Soil respiration was measured monthly. Important Findings We found that fresh leaves decomposed faster than their conspecific fallen litter. Although total microbial biomass and bacterial biomass were similar among treatments, soil fungal biomass was higher in fresh leaf than fallen litter treatments, resulting in greater values of the Fungal phospholipid fatty acids (PLFAs)/Bacterial PLFAs ratio. Fungal PLFA values were greater for Schima superba than the other species. The effect of litter type on soil respiration was species-dependent. Specifically, fallen litter released 35% more CO2 than fresh leaves of the conifer P. elliottii. The opposite pattern was observed in the broadleaf species whose fresh leaf treatments emitted 17%–32% more CO2 than fallen litter. Given future predictions that global climate change will cause more disturbances to forests, these results indicate that conifer and broadleaf forests in subtropical China may respond differently to increased fresh litter inputs, with net soil microbial respiration decreasing in conifer forests and increasing in broadleaf forests. [ABSTRACT FROM PUBLISHER]

Thousands of kilometers of shelterbelt plantations of Casuarina equisetifolia have been planted to protect the southeast coastline of China. These plantations also play an important role in the regional carbon (C) cycling. In this study, we examined plant biomass increment and C accumulation in four different aged C. equisetifolia plantations in sandy beaches in South China. The C accumulated in the C. equisetifolia plant biomass increased markedly with stand age. The annual rate of C accumulation in the C. equisetifolia plant biomass during 0–3, 3–6, 6–13 and 13–18 years stage was 2.9, 8.2, 4.2 and 1.0 Mg C ha−1 yr−1, respectively. Soil organic C (SOC) at the top 1 m soil layer in these plantations was 17.74, 5.14, 6.93, and 11.87 Mg C ha−1, respectively, with SOC density decreasing with increasing soil depth. Total C storage in the plantation ecosystem averaged 26.57, 38.50, 69.78, and 79.79 Mg C ha−1 in the 3, 6, 13 and 18- yrs plantation, with most of the C accumulated in the aboveground biomass rather than in the belowground root biomass and soil organic C. Though our results suggest that C. equisetifolia plantations have the characteristics of fast growth, high biomass accumulation, and the potential of high C sequestration despite planting in poor soil conditions, the interactive effects of soil condition, natural disturbance, and human policies on the ecosystem health of the plantation need to be further studied to fully realize the ecological and social benefits of the C equisetifolia shelterbelt forests in South China. [ABSTRACT FROM AUTHOR]

Chasing the active impurity: In the validation of a screening hit it was discovered that a polymeric trace impurity was responsible for the biological activity. Such a side product can be formed with similar compounds. During the investigations it was discovered that the negatively charged macromolecule interacts very efficiently with the protein surface of E. coli RNAP via electrostatic interactions. [ABSTRACT FROM AUTHOR]

Since wetland construction projects are becoming more commonplace, meaningful follow-up studies are needed to evaluate how these systems change over time. To that end, the objective of our study was to examine the temporal changes in plant community composition and water chemistry in two constructed wetlands. We investigated two wetland sites that were constructed in 2003 in northern Otsego County, NY, a county that is largely dominated by agriculture. Site 1 was previously an active cow pasture and site 2 was previously a wet meadow surrounded by agricultural fields. No active plant introduction was made during the construction; however, both sites were located in areas with many remnant wetlands and were connected to through-flowing streams. In 2004 (Year 1) and 2010 (Year 7), the plant community composition and nitrogen retention were assessed. We found that both sites experienced site-wide declines in plant species richness, including the loss of upland and facultative upland species and the unanticipated loss of facultative wetland and some obligate species. We propose that high water levels, which, at their maximum depth were >1.5 m deeper than in Year 1, maintained by landowners in the years after the initial survey, may have been responsible for the unexpected loss of wetland species. We also found that site 1 exhibited considerable nitrogen retention in both Year 1 and Year 7; however, N concentrations were low at site 2 in both years. [ABSTRACT FROM AUTHOR]