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Within the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) complex, two cryptic species, namely Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), are important invasive pests affecting global agriculture and horticulture. They were introduced into China sequentially in the mid-1990s and around 2003, respectively. Subsequently, the latter invader MED has outcompeted the earlier invader MEAM1, becoming the dominant population in the field. Although extensive studies have explored the underlying mechanisms driving this shift, the contribution of population genetics remains notably underexplored. In this study, we analyzed the genetic diversity and structure of 22 MED and 8 MEAM1 populations from various regions of China using mitochondrial DNA sequencing and microsatellite genotyping. Our results indicate low and moderate levels of genetic differentiation among geographically separate populations of MED and MEAM1, respectively. Median-joining network analysis of mtCOI gene haplotypes revealed no clear geographic structuring for either, with common haplotypes observed across provinces, although MED had more haplotypes. Comparative analyses revealed that MED presented greater genetic diversity than MEAM1 on the basis of two markers. Furthermore, analysis of molecular variance supported these findings, suggesting that while some genetic variation exists between populations, a significant amount is also present within populations. These findings reveal the population genetics of the two invasive cryptic species of the B. tabaci complex in China and suggest that the disparities in genetic diversity drive the displacement of their populations in the field. This work also provides valuable information on the genetic factors influencing the population dynamics and dominance of these invasive whitefly species. [ABSTRACT FROM AUTHOR]

Human cultivation facilitates the naturalization and subsequent invasion of non-native plant species through, for example, protection from predators or reducing environmental stochasticity. With the development of tourism, non-native plant species have been increasingly introduced into rural home gardens for landscape greening and amenity planting. However, few studies have examined non-native flora in rural home gardens, and in particular the importance of tourism in determining changes of garden non-native flora has not been scrutinized. In this study, we investigated non-native plant species in 135 home gardens across five rural tourism villages in tropical China. Attributes related to garden or household characteristics were also collected through interviews and questionnaires. A distance-based redundancy analysis was then performed to reveal the relationships between the non-native species composition and garden attributes. A total of 338 non-native plant species were recorded in the surveyed gardens. Among them, the majority (63%) were ornamentals, whereas 19% were for nutritional uses and 12% were spontaneous weeds. Gardening preference and distance to tourist attractions governed the non-native compositions, with gardens preferring cultural (ornamental) cultivation or gardens close to tourist attractions having more non-native species. These results highlight an increasing role of tourism in promoting non-native cultivation in rural gardens. Recommendations for species risk assessment, trade and supply regulation, and proper garden management are provided to help harness plant invasion along tourism development in rural China and other regions around the world. [ABSTRACT FROM AUTHOR]

As a major concern shared by parents globally, COVID-19 vaccine safety is typically being messaged to the public in a negative frame in many countries. However, whether the COVID-19 vaccine safety framing have an effect on parents when vaccinating their children is unclear. Here we implement an online survey with a convenience sample of 3,861 parents living in mainland China, all over 18 years old and with at least one child under 18. The parents were randomly assigned to receive information about COVID-19 vaccine safety in either a negative frame (incidence of side effects) or a positive frame (the inverse incidence of side effects), to compare parental reactions to a range of questions about communication, risk perception, trust, involvement and behavioral intention. We found that parents were more likely to regard vaccine safety as relevant to policy support and as a higher priority for government when receiving positively framed information (p = 0.002). For some specific subgroups, parents in positive framing group showed lower risk perception and higher trust (p<0.05). This suggests that positive framing of COVID-19 vaccine safety messages show more effective performance than negative framing in terms of involvement, as well as trust and risk perception in specific subgroups, which may lead to a reflection on whether to adjust the current widespread use of negative framing. Our findings inform how governments and health care workers strategically choose the framing design of COVID-19 vaccine safety information, and have important implications for promoting COVID-19 vaccination in children in the future. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) have serious environmental and economic impacts, especially in vulnerable areas of China. However, IAP richness distribution patterns, their driving factors, and the dynamic shifts in potential distribution areas remain elusive. We assessed IAP richness distribution patterns and drivers using 402 IAPs recorded in China at 88 926 occurrence points, and then predicted their potential distribution areas. The results show that IAP hotspots were mainly located in southeastern China, especially coastal areas of the South and East and large inland cities. Population density, gross domestic product (GDP), and four climate variables associated with precipitation and temperature jointly influenced the richness distribution pattern of all IAPs. Specifically, population density and GDP impacted the richness distribution pattern of narrow‐range IAPs, and population density, GDP, distance to the nearest national highway, and five climate variables affected the richness distribution pattern of widespread IAPs. Only GDP contributed significantly to the richness distribution pattern of the top 5% hotspot grid cells, whereas population density, GDP, and precipitation in the driest month (BIO14) significantly influenced the richness distribution patterns of hotspots for both the top 10% and top 20%. Prediction analysis demonstrated that southeastern China would have particularly high invasion risk under both current and future climate scenarios. Regions with increases in predicted species richness are more common (44.83–64.97%) than those with decreases, except under the Representative Concentration Pathway (RCP) 4.5 scenario. Climate change will contribute greatly to the expansion of potential IAP distribution areas under both optimistic (RCP 2.5) and pessimistic scenarios (RCP 8.5). The results of this study provide insights into the priority management of IAPs by developing promising strategies for the control and prevention of IAP invasion. [ABSTRACT FROM AUTHOR]

Changes in winter cloudy days (CDs) exert substantial impacts on agricultural production, public transport, and the solar photovoltaic (PV) power industry. However, the physical mechanism behind the variability of winter CDs over China remains largely unclear, making it challenging to predict the future dynamics of winter CDs. In this study, we explored the spatiotemporal features of winter CDs over China from 1961 to 2013 and identified two independent formation mechanisms associated with its leading mode. Then, we projected the future changes (2021–2099) in winter CDs under global warming constrained by the identified formation mechanisms. Results revealed that: (a) The leading mode of winter CDs from 1961 to 2013 presents a homogeneous pattern. The positive winter CDs anomaly is connected to the anomalous southerlies related to the Eurasian Rossby wave train triggered by the Barents Sea thermal forcing, as well as the Asia‐Pacific zonal geopotential height gradient induced by the convection over the Maritime Continent; (b) Selected state‐of‐the‐art climate models project a notable decrease in winter CDs in the Tibetan Plateau and southern China regions, and almost unchanged winter CDs over northern China, under global warming; (c) In contrast to present‐day mechanisms, in the future, the shift of the Eurasian mean flow will terminate the role of the Barents Sea thermal forcing. Instead, the enhanced convection over the Maritime Continent emerges as the primary contributor to the decline in winter CDs. Our findings provide valuable insights for policymakers in the solar PV industry, particularly in relation to the challenges faced under global warming. Plain Language Summary: Winter cloudy days (CDs) over China exhibit significant spatiotemporal variability, greatly impacting agriculture, transportation, and the solar photovoltaic (PV) power industry. However, the physical mechanism and future changes of winter CDs in China under global warming have not been extensively explored. We revealed two independent routes influencing the formation of winter CDs in China. Furthermore, state‐of‐the‐art climate models project a clear diminish in winter CDs over the Tibetan Plateau and southern China in the mid‐term and long‐term under global warming, providing valuable guidance to policymakers involved in the solar PV power industry. Key Points: The uniform pattern observed in the dominant mode of winter cloudy days (CDs) over China can be attributed to the anomalous southerlies in East AsiaThe warming Arctic forcing and negative convection anomalies over the Maritime Continent both lead to the anomalous southerlies in East AsiaWinter CDs will diminish with enhanced greenhouse forcing, owing to a shift in Eurasian westerly jet affecting the Arctic forcing on East Asian anomalous southerlies [ABSTRACT FROM AUTHOR]

BACKGROUND: Plant invasions are a global concern. In eastern China, bamboo is rapidly expanding, negatively influencing neighbouring forest communities. However, studies on how bamboo invasion affects belowground communities, especially for soil invertebrates, are still lacking. In the present study, we focused on a highly abundant and diverse fauna taxon – Collembola. Collembola communities have three typical life‐forms (i.e., epedaphic, hemiedaphic, and euedaphic) inhabiting different soil layers and playing distinct roles in ecological processes. Specifically, we studied their abundance, diversity, and community composition at the three stages of bamboo invasion: uninvaded secondary broadleaf forest, moderately invaded mixed bamboo forest, and completely invaded bamboo (Phyllostachys edulis) forest. RESULTS: Our results showed that bamboo invasion negatively influenced Collembola communities by decreasing their abundance and diversity. Moreover, Collembola life‐forms differed in their responses to bamboo invasion, with surface‐dwelling Collembola being more vulnerable to bamboo invasion than soil‐living Collembola. CONCLUSION: Our findings indicate differential response patterns to bamboo invasion within Collembola communities. The negative effects of bamboo invasion on soil surface‐dwelling Collembola may further influence ecosystem functioning. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The invasion of exotic plants in the river–lake ecotone has seriously affected the nutrient cycling processes in wetland soil. The South American species Alternanthera philoxeroides (Mart.) Griseb. is rapidly invading the river–lake ecotone in subtropical China, and has become the dominant species in the river–lake ecotone. However, there have been few studies on the effects of A. philoxeroides invasion on soil phosphorus (P) cycling and bioavailability in this ecotone. Here, we measured the bioavailable P fractions, physicochemical properties and nutrient content in the surface soils of the native plant (Zizania latifolia (Griseb.) Turcz and Nelumbo nucifera Gaertn.) communities and the adjacent invasive A. philoxeroides communities in three river–lake ecotones with different nutrient substrates in the subtropical Dongting Lake basin over a 3‐year period to reveal the effects of A. philoxeroides invasion on the morphology and concentrations of soil bioavailable P. The principal coordinate analysis results showed that the A. philoxeroides invasion significantly altered the bioavailable P concentrations in the soil of native plant communities in the different river–lake ecotones, and this effect was not disturbed by the heterogeneity of the soil matrix. However, the effects of invasion into different native plant communities on the fractions of soil bioavailable P were different. Compared with native Z. latifolia and N. nucifera communities, A. philoxeroides invasion increased the concentration of inorganic P by 39.5% and 3.7%, respectively, and the concentration of organic P decreased by 32.7% and 31.9%, respectively. In addition, the invasion promoted P cycling and accumulation in the river–lake ecotone, which resulted in average decreases in the soil N:P and C:P ratios of 7.9% and 12.5%, respectively. These results highlight the impact of exotic plant invasions on nutrient cycling in wetland ecosystems in the river–lake ecotone, and this process may be detrimental to the late recovery of native plants. [ABSTRACT FROM AUTHOR]

Due to the rapid development of China's economy, the demand for wood is steadily increasing. Eucalyptus species have been introduced in large quantities because of their fast growth, strong adaptability, and wide utility. To understand the phenological changes in introduced Eucalyptus in its new range, we carried out a field investigation to examine leaf functional and chemical defense traits of three introduced species (E. saligna, E. grandis and E. robusta) over latitudinal and altitudinal gradients in southern China. We sampled multiple stands of each species, and measured the leaf physical characteristics (e.g., leaf width, leaf thickness, and specific leaf area [SLA]), leaf nitrogen (N) and phosphorus (P) content, and phenolic compounds. We found that many functional traits (e.g., leaf size and thickness) decreased at lower latitudes, especially in E. grandis, possibly to reduce heat and water loss under higher temperatures. In E. grandis, we found that leaf P was lower at higher latitudes and altitude, and phenolics increased with elevation, while in E. robusta, both leaf N and P decreased with altitude. These findings suggested that both species were more conservative in resource allocation, with E. grandis possessing enhanced chemical defenses in response to the conditions experienced at higher elevations. In addition, we found the tree populations at the northern range limit of E. robusta had lower SLA, suggesting a more conservative growth strategy, In contrast, small populations in the northern part of the ranges of E. grandis had higher SLA, indicating range expansion at the edge of the species' geographic distribution. Overall, it is particularly important to consider intraspecific trait differences across wide geographic areas when studying the spread of invasive species in the new range. [ABSTRACT FROM AUTHOR]

Simple Summary: The stalk-eyed seed bug Chauliops fallax is an important agricultural pest of soybean and was first reported to occur outside East Asia. Here, the native evolutionary history, recent invasion history, and potential invasion threats of C. fallax were reported for the first time based on population genetic methods and ecological niche modelling. Four native genetic groups (EA, WE, TL, and XZ) and an east–west differentiation pattern consistent with the geographical characteristics of three-step landforms were well supported in China. The Kashmir sample was found to come from a recent invasion event, and the invasive source was determined to be the populations of the coastal areas of southern China. North America might have high a risk of invasion, which poses a serious threat to local soybean production. Our results provided new insights into the monitoring and management of Chauliops fallax in the early invasion stage. The short stay at the beginning of the invasion process is a critical time for invasive species identification and preventing invasive species from developing a wider distribution and significant economic impact. The stalk-eyed seed bug Chauliops fallax is an important agricultural pest of soybean and was first reported to occur outside East Asia. Here, we reported the native evolutionary history, recent invasion history, and potential invasion threats of C. fallax for the first time based on population genetic methods and ecological niche modelling. The results showed that four native East Asian genetic groups (EA, WE, TL, and XZ) were well supported, showing an east-west differentiation pattern consistent with the geographical characteristics of three-step landforms in China. Two main haplotypes existed: Hap1 might have experienced a rapid northwards expansion process after the LGM period, and Hap5 reflected local adaptation to the environment in southeastern China. The Kashmir sample was found to come from the recent invasion of populations in the coastal areas of southern China. Ecological niche modelling results suggested that North America has a high risk of invasion, which might pose a serious threat to local soybean production. In addition, with future global warming, the suitable habitat in Asia will move towards the higher latitude region and gradually deviate from the soybean planting area, which indicates the threat of C. fallax to soybean production in Asia will decrease in the future. The results could provide new insights into the monitoring and management of this agricultural pest in the early invasion stage. [ABSTRACT FROM AUTHOR]

In the context of global warming, the general increase in temperature has led to an increase in heatwave events, as well as a dramatic intensification of economic losses and social risks. This study employs the latest intensity–area–duration (IAD) framework that takes into account the temporal continuity and spatial dynamics of extreme events to identify regional heatwave events, and extracts key parameters of heatwave events to study the associated changes in frequency, intensity, influence area, and duration in seven geographic subregions of China in the 1979–2018 period. Heatwaves of all durations increased in frequency and intensity during the research period, with shorter heatwaves increasing in frequency and intensity at a faster rate than longer heatwaves. Among the seven geographic subregions, Xinjiang (XJ) and Southern China (SC) are the regions with the most frequent heatwave occurrence, while the Southwest (SW) and SC have the highest increase in heatwave frequency. In terms of regional distributions, XJ has the strongest heatwave event intensity and the largest affected area, while SC has the longest duration. However, in terms of spatial trends, SC, XJ, and the SW have the highest rates of intensity growth, influence area, and duration, respectively. In addition, heatwaves with extended durations and vast influence areas are more likely to occur in SC, and their frequency is on the rise. During the study period, the intensity, influence area, and length of heatwave occurrences in China exhibited an upward tendency, and it was shown that the longer the duration, the greater the intensity and the broader the influence area. In addition, the evolutionary characteristics of heatwave events with the longest duration indicate a certain consistency in their intensity and influence. These findings can contribute to the development of strategies to prepare for and mitigate the adverse effects of heatwave occurrences. [ABSTRACT FROM AUTHOR]

Interspecific competition determines the invasive capability of alien plants. Phytolacca americana, one of the most destructive invasive plants in China, was first discovered and recorded in China in 1935. Since its arrival, the rapid expansion of the species has driven out a native congener, Phytolacca acinosa. In this study, we assessed the competitive interaction of the invasive P. americana the native P. acinosa in a pot experiment at Yunnan University. Our results indicate that P. americana severely inhibits the growth and reproduction of P. acinosa. Furthermore, P. americana demonstrated a superior resistance against both insect predation and bacterial infection. We suggest that this improved tolerance against herbivory and potentional pathogen damage may be a cornerstone to the invasive success of Phytolacca americana. [ABSTRACT FROM AUTHOR]

Coastal environments are highly threatened by invasive alien plants (IAP), and Remote Sensing (RS) may offer a sound support for IAP detection and mapping. There is still a need for an overview of the progress and extent of RS applications on invaded coasts that can help the development of better RS procedures to support IAP management. We conducted a systematic literature review of 68 research papers implementing, recommending, or discussing RS tools for IAP mapping in coastal environments, published from 2000 to 2021. According to this review, most research was done in China and USA, with Sporobolus (17.3%) being the better studied genus. The number of studies increased at an accelerated rate from 2015 onwards, coinciding with the transition from RS for IAP detection to RS for invasion modeling. The most used platforms in the 2000s were aircraft, with satellites that increased from 2005 and unmanned aerial vehicles after 2014. Frequentist inference was the most adopted classification approach in the 2000s, as machine learning increased after 2009. RS applications vary with coastal ecosystem types and across countries. RS has a huge potential to further improve IAP monitoring. The extension of RS to all coasts of the world requires advanced applications that bring together current and future Earth observation data. [ABSTRACT FROM AUTHOR]

Identifying the distribution dynamics of invasive alien species can help in the early detection of and rapid response to these invasive species in newly invaded sites. Ageratina adenophora, a worldwide invasive plant, has spread rapidly since its invasion in China in the 1940s, causing serious damage to the local socioeconomic and ecological environment. To better control the spread of this invasive plant, we used the MaxEnt model and ArcGIS based on field survey data and online databases to simulate and predict the spatial and temporal distribution patterns and risk areas for the spread of this species in China, and thus examined the key factors responsible for this weed's spread. The results showed that the risk areas for the invasion of A. adenophora in the current period were 18.394° N–33.653° N and 91.099° E–121.756° E, mainly in the tropical and subtropical regions of China, and densely distributed along rivers and well-developed roads. The high-risk areas are mainly located in the basins of the Lancang, Jinsha, Yalong, and Anning Rivers. With global climate change, the trend of continued invasion of A. adenophora is more evident, with further expansion of the dispersal zone towards the northeast and coastal areas in all climatic scenarios, and a slight contraction in the Yunnan–Guizhou plateau. Temperature, precipitation, altitude, and human activity are key factors in shaping the distribution pattern of A. adenophora. This weed prefers to grow in warm and precipitation-rich environments such as plains, hills, and mountains; in addition, increasing human activities provide more opportunities for its invasion, and well-developed water systems and roads can facilitate its spread. Measures should be taken to prevent its spread into these risk areas. [ABSTRACT FROM AUTHOR]

Aim: We test (1) whether invasive angiosperm (flowering plant) species are a phylogenetically clustered subset of all naturalized angiosperm species within an angiosperm assemblage, (2) whether more harmful invasive species are more strongly, or less strongly, related to each other, (3) whether the result of the first test is consistent with those for geographic regions distributed in substantially different climatic conditions, and (4) whether patterns of phylogenetic relatedness for invasive species in regions across climatic gradients are consistent with those for overall naturalized species. Location: China. Time period: Current. Taxon: Angiosperms (flowering plants). Methods: We recognized 28 province‐level regions in China and collated naturalized and invasive species lists of angiosperms for each region. Two phylogenetic metrics (i.e., net relatedness index and nearest taxon index), which represent different depths of evolutionary history, were used to quantify phylogenetic relatedness of angiosperms in China and in each region. Values of the metrics of phylogenetic relatedness were related to temperature and precipitation. Results: At the national scale, invasive assemblage is a phylogenetically clustered subset of the naturalized species pool. More harmful invasive species are more strongly clustered. At the regional scale, both naturalized and invasive species are phylogenetically clustered subsets of the national naturalized species pool. Furthermore, invasive species in regional floras are also phylogenetically clustered subsets of their respective regional naturalized species pools. Main conclusions Invasive angiosperm species are a phylogenetically clustered subset of naturalized angiosperm species. More harmful invasive species are more strongly clustered with respect to their naturalized species pools, compared to less harmful invasive species. Our findings have significant implications to predicting and controlling invasive species based on phylogenetic relatedness among naturalized species. [ABSTRACT FROM AUTHOR]

To support future solar energy deployment in China, long‐term changes in solar energy resources over China were investigated based on high‐resolution dynamical downscaling simulations under three emission scenarios. First, an evaluation of model performance was conducted through comparison with station and ERA5 data, which indicated that although consistent overestimation was found, the spatial distribution and intra‐annual variation of solar radiation were captured well by ensemble simulation, showing added value over regions with complex topography as well. Then, the trends of the solar power output from photovoltaic (PV) systems during 2020–2099 were projected, characterized by an increase in east and central China, and a consistent decrease in the solar‐energy‐abundant regions (e.g., northeast China, the Tibetan Plateau, and northwest China) under the three scenarios. Except for under the low emission scenario, the regional averaged trends of PV were projected to decrease consistently over China in all four seasons, with significant magnitude apparent in both spring and winter. In addition, a more intense magnitude of decline was found under the higher emission scenario, with more subregions with a significant trend and higher intra‐annual and inter‐annual variability. However, it seems that the emission scenarios impact the spatial pattern only remarkably in the late century, however strengthened the decreasing magnitude in all future periods. In addition, results indicate decline in the future PV potential over most of subregions of China due to reduced radiation and increased temperature, but for the decrease over Tibetan Plateau the reduced wind speed also act as an important factor. Plain Language Summary: The long‐term goal of carbon neutrality in China involves new requirements for the development and utilization of solar energy. The present study was motivated by supporting future solar energy deployment at local scales. However, due to data limitations, relatively little effort has been made to project long‐term changes in solar energy over different subregions of China. Accordingly, we investigated this based on a set of high‐resolution dynamical downscaling simulations under different climate scenarios, and found that the higher emission scenarios reinforce the magnitude of the decline in solar energy and result in higher inter‐annual variability. These findings suggest an increased need for constraining emissions for the benefit of solar energy. In addition, we found that radiation will likely be the most important factor related to future changes in solar resources over most of subregions under RCP2.6 scenario, however the effect of wind speed should not be ignored over Tibetan Plateau. Key Points: Despite some overestimation, the spatial distribution and intra‐annual variation of solar radiation were captured well, showing added valuesFuture solar power were projected to generally increase in east and central China but decrease in solar‐energy‐abundant regionsRadiation was the most robust factor for future solar energy trend over China, however wind speed can not be ignored over Tibetan Plateau [ABSTRACT FROM AUTHOR]

In recent years, positive and negative effects of urbanization on forest ecosystem have been reported by many studies, while some uncertainties about the impact of urbanization-induced spatial heterogeneity of environmental factors on forest systems still remain unclear. In this study, we analyzed the urbanization effects on sap flux of a common subtropical evergreen tree species Schima superba along an urban–rural gradient in Guangdong Province, South China, and identified the consistency of these results among different groups (evergreen, deciduous, and coniferous species) using data from 83 previously published studies in China. The mean sap flux density (Fd) of S. superba in Xiaoqingshan (XQS), Heshan (HS), Dinghushan (DHS), and Shimentai (SMT), along the urban–rural gradient was 40.9 g m−2 s−1, 32.1 g m−2 s−1, 17.0 g m−2 s−1, and 17.5 g m−2 s−1, respectively, presenting a decreasing trend with the diminishing urbanization. This pattern in Fd tended to enlarge with tree size and was well confirmed by the enhanced leaf transpiration rate (by 119%) and photosynthetic rate (by 8.8%) for the S. superba in another urbanization gradient from the urban (Hangzhou, denoted as "HZ") to rural sites (Jiande, denoted as "JD") in Zhejiang Province, East China, which has similar climatic condition and urbanization with Guangdong Province. We attributed such positive effects to the decreased sapwood density and specific leaf area (SLA), as well as the increased Huber value (sap wood area/leaf area) and the sap wood specific hydraulic conductivity (KS). We also found that pollutant emission exerted more impact on Fd than climatic factors change, since the variation of the latter was not large enough to cause significant change of Fd under the same climatic zone. In addition, we conducted a principal component analysis (PCA) based on the published 83 studies. Results showed Fd of evergreen tree species was related positively to principle 1 and negatively to principle 2, respectively, whereas the Fd of deciduous broadleaf and coniferous tree species was positively and negatively related to both principles, respectively. This study demonstrated the potential impact of urbanization-related pollutant emission changes on water use of forest trees and the growth among different groups. [ABSTRACT FROM AUTHOR]

Aims The introduction of Robinia pseudoacacia (RP) has some effects on undergrowth herbaceous plants (UH), soil properties and their relationships, which may be related to the vegetation zone. However, few studies have tested effects of RP on UH and soil over a large-scale area of the Loess Plateau. Methods The study area consisted of three vegetation zones (the steppe, forest-steppe and forest zone). Two canopy plant types were selected: RP stands and adjacent native vegetation. We measured five leaf functional traits: leaf carbon content (LC), leaf nitrogen content (LN), leaf phosphorus content (LP), specific leaf area (SLA) and leaf tissue density (LTD). The functional diversity, species diversity and community-weighted mean (CWM) traits were calculated. Important Findings (i) CWM.LN, CWM.LP and CWM.SLA increased significantly, whereas CWM.LC and CWM.LTD decreased significantly in the three vegetation zones, compared with the native communities. (ii) Species diversity, functional diversity and community biomass decreased in the steppe zone, increased in the forest zone, and did not differ significantly in the forest-steppe zone. (iii) We found only soil organic carbon (P < 0.05) and soil total nitrogen (P < 0.05) in the forest zone decreased significantly compared with the native plots. (iv) The relationship between UH and soil properties was affected by RP and the vegetation zone. Overall, the effect of RP on UH and soil properties was associated with the vegetation zone. This result is of great significance to the planning of restoration and reconstruction of artificial forests in the Loess Plateau. [ABSTRACT FROM AUTHOR]

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A crucial step in the application of the Weather Research and Forecasting (WRF) model to regional climate research is the selection of the proper combinations of physical parameterizations. In this study, we examined the performance of various parametrization schemes in the WRF model in terms of precipitation and temperature over the Haihe river basin in northern China. The WRF experiments were integrated with 13-km horizontal resolution and driven by ERA-INTERIM reanalysis data over the period from 1st June to 31st August, 2016. Fifty-eight members of physics combinations derived from five types of physics options were assessed against the available observational temperature and precipitation data by utilizing the multivariable integrated evaluation (MVIE) method. Our results indicated that the best combination of physical schemes consisted of CAM5.1 microphysics, MRF PBL, BMJ cumulus, CAM Longwave/Shortwave radiation, and Noah Land Surface schemes. The optimal setup's differences with the observational data, temporally and spatially, were much smaller than other setups in terms of surface air temperature and precipitation, which proves that the optimal setup showed better performance than the other setups. Further analysis of the sensitivities of model outputs to different types of physics options suggests that the microphysics, planetary boundary layer (PBL), and cumulus schemes have a more significant impact on the model performances than the radiation scheme and Land Surface schemes. [ABSTRACT FROM AUTHOR]

Aim: Biological invasions threaten biodiversity globally. Large‐scale studies of non‐native plant species invasiveness typically focus on identifying ecological differences between naturalized and invasive species that account for their spread from sites of initial establishment (i.e., invasion success). However, invasive species differ widely in the magnitude of their impacts, suggesting the characteristics that favour invasion success might not necessarily predict the consequences of that invasion. Here we test whether those factors that increase the probability of plant species invasion also explain the severity of impacts. Location: China. Methods: We compiled a database of the invasiveness, biogeographic origins, life history traits, and introduction history for 538 non‐native plants in China and modelled differences in (a) naturalized and invasive species; (b) the spatial extent of invasion; and, (c) the severity of invasion impacts among successful invaders. Results: Invasion success and the spatial extent of invasion shared similar influencing factors. However, these clearly differed from the predictors of severe invasion impacts. Unintentionally introduced non‐native plants with shorter life cycles and longer residence times were more likely to become invasive and to invade a larger area, while taller plants introduced from the Americas tended to have more severe impacts on the native ecosystems of China. Main Conclusions: These results illustrate the different roles of introduction history, biogeographical origin and biological traits in determining the invasion success and spatial extent of invasion versus the severity of invasive species impacts. We suggest that factors associated with evolutionary adaptation and population expansion might determine invasion success and extent, while traits related to the relative competitive ability of invasive species determine the severity of impacts. Identifying specific characteristics of species that distinguish among successful invaders most likely to result in more severe impacts could help with planning more effective interventions. [ABSTRACT FROM AUTHOR]

Trade has long been considered a potent pathway throughout the global spread of alien species, while related links between them remain poorly tested at a global scale. We therefore took sweet cherry, an emerging commercial fresh fruit, as a case study to explore the international trade patterns and its impact on global pest transfer. We used data on annual bilateral trade volume between countries from 1961 to 2016 (from FAOSTAT) and the current occurrence of sweet cherry pests per country (from CABI). The international sweet cherry trade was highly concentrated, especially in Europe with obvious intracontinental self‐selling. Cluster analysis and nonmetric multidimensional scaling divided the 66 producing countries into five groupings on pest compositional similarities, for which both the short geographical distance and trade pattern above‐mentioned might be responsible. Meanwhile, the country‐level pest species richness increased linearly with the log of production and proportionally over‐represented in specific countries with large import volumes. Overall, ongoing regional and global cooperation for most trading countries should be promoted to improve international regulations, and to maximize the benefits of pest records in terms of facilitating trade and reducing invasion risks of alien species. This is particularly essential for China, who has already granted sweet cherry market permits to 10 main producing countries. Of those, all but three were in the same grouping as China which poses the greatest risk for pest introduction and establishment. [ABSTRACT FROM AUTHOR]

To resolve a series of ecological and environmental problems over the Loess Plateau, the "Grain for Green Program" (GFGP) was initiated at the end of 1990s. Following the conversion of croplands and bare land on hillslopes to forests, the Loess Plateau has displayed a significant greening trend, which has resulted in soil erosion being reduced. However, the GFGP has also affected the hydrology of the Loess Plateau, which has raised questions regarding whether the GFGP should be continued in the future. We investigated the impact of revegetation on the hydrology of the Loess Plateau using relatively high-resolution simulations and multiple realizations with the Weather Research and Forecasting (WRF) model. Results suggest that revegetation since the launch of the GFGP has reduced runoff and soil moisture due to enhanced evapotranspiration. Further revegetation associated with the GFGP policy is likely to further increase evapotranspiration, and thereby reduce runoff and soil moisture. The increase in evapotranspiration is associated with biophysical changes, including deeper roots that deplete deep soil moisture stores. However, despite the increase in evapotranspiration, our results show no impact on rainfall. Our study cautions against further revegetation over the Loess Plateau given the reduction in water available for agriculture and human settlements and the lack of any significant compensation from rainfall. [ABSTRACT FROM AUTHOR]

Background: Solidago canadensis is a notorious invasive species from North America that is spreading across East China. It is invading some coastal grasslands and replacing native grass species. The effects of the S. canadensis invasion on soil nutrient cycling in the grasslands remain unclear. This study examined the effects of the invasion of S. canadensis on macronutrient accumulation in species aboveground part and soil. Methods: Aboveground biomass, macronutrient (N, P, and K) pools in biomass, litter mass and decomposition rates, soil macronutrient availability and soil microbial biomass and enzyme activity that were related to nutrient transformation were compared between plots invaded by S. canadensis and uninvaded plots dominated by three different native grass species: Phacelurus latifolius , Phragmites australis , and Imperata cylindrica. Results: S. canadensis had higher aboveground biomass, higher leaf N, P, and K concentrations, and consequently, a larger macronutrient pool size in the standing biomass. S. canadensis also produced more litter with higher N, P, and K concentrations and faster decomposition rates. The S. canadensis invasion did not change the total N, P, and K concentration in the topsoil (0–10 cm), but the invasion did increase their availability. The S. canadensis invasion did not increase the total soil organic matter (TSOM) content but did increase the soil microbial biomass and the activities of urease, alkaline phosphatase, invertase, amylase, and glucosidase in the topsoil. Conclusion: The invasion of S. canadensis accelerates the macronutrient cycling rate via increases in aboveground productivity and nutrient accumulation in standing biomass, faster nutrient release from litter and higher soil microbial activity. An enhanced nutrient cycling rate may further enhance its invasiveness through a positive feedback on soil processes. [ABSTRACT FROM AUTHOR]

Global awareness of sustainability issues is growing rapidly, and business organizations are called to address wider social and environmental concerns along with economic performance. However, limited systematic knowledge exists on the interactions between forest industries and natural ecosystems. We thus investigated the role of ecosystem services in the context of China's forest sector. A qualitative research approach was used to elicit company external expert viewpoints on the topic. Our analysis focused on three themes: (1) forest company dependencies and impacts on ecosystem services; (2) business risks arising from dependencies and impacts; and (3) risk response strategies. The interviewed 20 experts identified a series of forest company dependencies and impacts (including negative and positive impacts) on several ecosystem services. The extent of dependencies and impacts is largely influenced by the business portfolio of the company. The perceived business risks include intense competition and the consequently increasing price for natural resources, which would affect forest company business plans, costs and outputs. The suggested strategies for turning risks into opportunities include outsourcing wood, changing production focus, promoting industrial upgrading and implementing regular assessments of corporate dependencies and impacts on ecosystem services. The findings of our study can guide companies' decision-making in managing forest ecosystems sustainably. [ABSTRACT FROM AUTHOR]

Aims Invasive species occurrence and their effects on biodiversity may vary along latitudes. We examined the occurrence (species cover) and relative dominance (importance value) of invasive alligator weed, Alternanthera philoxeroides, in its terrestrial habitat in China through a large-scale latitudinal field investigation. Methods We established 59 plots along the latitudinal transect from 21°N to 37°N. We recorded species name, abundance, height and individual species coverage of plants in every quadrat. We then measured α-species diversity variations associated with the A. philoxeroides community across the latitudinal range. We also analyzed the effect of latitude on plant species' distributions in this community by using canonical correspondence analysis (CCA). Important Findings We found that species cover and importance value of A. philoxeroides increased in areas <35°N, but decreased at higher latitudes. Lower latitudes supported greater species diversity than higher latitudes. Small-scale invasion of A. philoxeroides was associated with higher species diversity, but community diversity was lower when A. philoxeroides species cover exceeded 36%. Community plant species changed from mesophyte to hygrophyte gradually from low to high latitude. Our research suggests that latitude had significant influences on community diversity which interacted with the biotic resistance of a community and impact of invasion. Consequently, A. philoxeroides may become more invasive and have greater negative impacts on community species diversity in higher latitudes as global climate changes. [ABSTRACT FROM AUTHOR]

Controlling the invasion of non-native fish species necessitates a complete understanding of the distribution of these species and the key factors that influence such distribution. In order to research the situation of non-native fish and the relevant influencing factors in the Liao River Basin, we investigated and analyzed the characteristics of the distribution and the trophic levels of non-native fish species, as well their response to different types of factors in the basin. Nine non-native fish species were found during the investigation, and the trophic levels of these species ranged between 2.00 and 3.84. The results of generalized linear models indicate that the distribution of non-native fish species in the basin is mainly related to anthropogenic activities, socioeconomic development, and climate. The southeastern part of the Liao River Basin is conducive to the distribution of non-native fish species. Furthermore, on a spatial scale, we also found that the mean trophic level of non-native fish species was not correlated with anthropogenic activities and socioeconomic development in the Liao River Basin. By providing evidence for the links between non-native fishes and different types of factors, our study contributes to increasing the relevant references for and experiences in the early detection and management of non-native fishes on a basin scale. [ABSTRACT FROM AUTHOR]