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Aim: If the positive occupancy–abundance relationship prevails, locally abundant species are widely distributed. Although broadly supported, studies on lake fishes have thus far contributed little to this topic, especially at intermediate and small spatial scales. Here, the main objective was to investigate the relationship between occupancy and abundance of lake fish species within a large lake, as well as examine the relative importance of ecological niches, functional traits and phylogenetic relatedness in forming the relationship. Location: Poyang Lake, China. Taxon: Fishes. Methods: We calculated occupancy and mean abundance for 78 fish species and estimated niche position and niche breadth for each species based on a set of environmental variables. Additionally, we generated four functional trait vectors and one phylogenetic vector, describing trait similarity and phylogenetic relatedness, respectively. Linear models, hierarchical partitioning analyses and boosted regression trees were used in combination to explore the relative role of niche position, niche breadth, trait vectors and phylogenetic relatedness in determining fish occupancy, abundance and their relationship. Results: Occupancy and mean abundance of fish species in Poyang Lake showed a significantly positive and rather strong interspecific relationship. Interspecific variations in fish occupancy and abundance were well accounted for by niche position, followed by niche breadth. Nonetheless, trait vectors and phylogenetic relatedness were of minor importance in affecting fish occupancy and abundance. Additionally, occupancy was better explained than abundance by the predictor variables used, which was shown by both linear models and boosted regression trees. Main Conclusions: This study suggests that the positive correlation between occupancy and abundance also occurs in lake fish species. Furthermore, ecological niche features, especially niche position, were more important than functional traits and phylogenetic relatedness in accounting for occupancy and abundance of fish species in Poyang Lake. [ABSTRACT FROM AUTHOR]

Picea jezoensis (Siebold & Zucc.) Carrière forests are distributed in Korea and China and are crucial for phytogeographical research. Implementing conservation policies encompassing multiple species is necessary to conserve endangered species, particularly monitoring coexisting species and their interactions within an ecological network. Here, we identified plants within P. jezoensis forests in East Asia as generalist species to contribute foundational data for biodiversity conservation. We examined 91 standardized sites through the Braun-Blanquet method, while generalist indices were calculated using Levin's method. The top 5% of generalists in the P. jezoensis forests were Acer komarovii (0.7409), Betula ermanii (0.7214), Asarum sieboldii (0.7002), Lepisorus ussuriensis (0.6977), Acer pseudosieboldianum (0.6915), Tripterygium regelii (0.6876), Thelypteris phegopteris (0.6771), Dryopteris expansa (0.6745), Sorbus commixta (0.6642), and Rhododendron schlippenbachii (0.6625). Correlation analysis between ecological factors and generalist species revealed that the coverage of Abies spp., Acer spp., and Rhododendron spp. and the species diversity index were influenced by altitude. Convex hull analysis revealed that pteridophytes and broad-leaved plants regenerated through stump sprouts occupy ecological niche spaces, indicating diverse habitats within P. jezoensis forests. This study highlights the importance of the simultaneous monitoring of multiple species to conserve ecosystem health and offers broader implications for ecological understanding. [ABSTRACT FROM AUTHOR]

Zhujiangyuan Nature Reserve, located in Qujing City, Yunnan Province, China, is reported with high fauna and floral diversity, while the fungal diversity of the region is poorly documented. During the summer season in 2023, decaying wood-inhabiting microfungi were collected from different microhabitats. The novel species were identified based on morphological characteristics and phylogenetic analyses (based on combined datasets of ITS , LSU , SSU , tef1-α, and rpb2 regions). Two species belong to Dothideomycetes (viz., Spegazzinia zhujiangyuanensis sp. nov. and Phaeoseptum zhujiangyuanense sp. nov. in Pleosporales) while the other one resides in Sordariomycetes (Synnemasporella fanii sp. nov. in Diaporthales). The results are in conformity with the earlier studies that predicted higher fungal diversity in this region. [ABSTRACT FROM AUTHOR]

Background: In recent years, global concern over increasing multidrug resistance (MDR) among various Salmonella serotypes has grown significantly. However, reports on MDR Salmonella Paratyphi B remain scarce, let alone the extensively drug-resistant (XDR) strains. Methods: In this retrospective study, we investigated the isolates of Salmonella Paratyphi B in Jiangsu Province over the past decade and carried out antimicrobial susceptibility tests, then the strains were sequenced and bioinformatics analyses were performed. Results: 27 Salmonella Paratyphi B strains were identified, of which the predominant STs were ST42 (11), ST86 (10), and ST2814 (5). Among these strains, we uncovered four concerning XDR Salmonella Paratyphi B ST2814 strains (4/5) which were previously unreported. These alarmingly resistant isolates showed resistance to all three major antibiotic classes for Salmonella treatment and even the last resort treatment tigecycline. Bioinformatics analysis revealed high similarity between the plasmids harbored by these XDR strains and diverse Salmonella serotypes and Escherichia coli from China and neighboring regions. Notably, these four plasmids carried the ramAp gene responsible for multiple antibiotic resistance by regulating the AcrAB-TolC pump, predominantly originating from China. Additionally, a distinct MDR ST42(1/11) strain with an ICE on chromosome was also identified. Furthermore, phylogenetic analysis of global ST42/ST2814 isolates highlighted the regional specificity of these strains, with Jiangsu isolates clustering together with domestic isolates and XDR ST2814 forming a distinct branch, suggesting adaptation to local antibiotic pressures. Conclusions: This research underscores the pressing need for closely monitoring the MDR/XDR Salmonella Paratyphi B, particularly the emerging ST2814 strains in Jiangsu Province, to effectively curb its spread and protect public health. Moreover, surveillance should be strengthened across different ecological niches and genera to track resistance genes and horizontal gene transfer elements under the concept of "ONE HEALTH". [ABSTRACT FROM AUTHOR]

The relationship between bryophyte community characteristics, alterations in species diversity, and microhabitat characteristics on various types of urban walls remains ambiguous. This study investigates the distribution and habitat characteristics of bryophytes on various types of urban walls in karst areas. The α and β diversity indices were employed to examine the variation of bryophytes on these walls. Additionally, a canonical correspondence analysis was conducted to analyze the relationship between bryophyte species composition and their microhabitat. The results showed that: (1) There were 14 families, 32 genera, and 80 species of wall bryophytes (including six species of liverworts) on urban walls. Brachytheciaceae, Pottiaceae, and Hypnaceae were the dominant families. Bryophyte species were most abundant on stone retaining walls, followed by concrete revetment. Bryophytes were mainly distributed in the face and base of concrete walls, the top, face, and base of stone walls, and the top of brick walls. (2) The species distribution across the nine types of walls was highly uneven, stone retaining walls exhibited the highest species diversity, while concrete revetment and freestanding walls demonstrated strong habitat heterogeneity. (3) The species composition of wall bryophytes was intricately linked to the properties of the wall and micro-environmental factors, with wall temperature and air humidity being the key determinants. These findings can serve as a benchmark for assessing the diversity and ecosystems of urban wall bryophytes. By enhancing the conservation and restoration of various types of wall bryophytes, we can bolster the self-sustaining mechanisms of urban ecosystems. [ABSTRACT FROM AUTHOR]

Disentangling how climate oscillations and geographical events significantly influence plants' genetic architecture and demographic history is a central topic in phytogeography. The deciduous ancient tree species Ulmus macrocarpa is primarily distributed throughout Northern China and has timber and horticultural value. In the current study, we studied the phylogenic architecture and demographical history of U. macrocarpa using chloroplast DNA with ecological niche modeling. The results indicated that the populations' genetic differentiation coefficient (NST) value was significantly greater than the haplotype frequency (GST) (p < 0.05), suggesting that U. macrocarpa had a clear phylogeographical structure. Phylogenetic inference showed that the putative chloroplast haplotypes could be divided into three groups, in which the group Ⅰ was considered to be ancestral. Despite significant genetic differentiation among these groups, gene flow was detected. The common ancestor of all haplotypes was inferred to originate in the middle–late Miocene, followed by the haplotype overwhelming diversification that occurred in the Quaternary. Combined with demography pattern and ecological niche modeling, we speculated that the surrounding areas of Shanxi and Inner Mongolia were potential refugia for U. macrocarpa during the glacial period in Northern China. Our results illuminated the demography pattern of U. macrocarpa and provided clues and references for further population genetics investigations of precious tree species distributed in Northern China. [ABSTRACT FROM AUTHOR]

Terrestrial geothermal springs are physicochemically diverse and host abundant populations of Archaea. However, the diversity, functionality, and geological influences of these Archaea are not well understood. Here we explore the genomic diversity of Archaea in 152 metagenomes from 48 geothermal springs in Tengchong, China, collected from 2016 to 2021. Our dataset is comprised of 2949 archaeal metagenome-assembled genomes spanning 12 phyla and 392 newly identified species, which increases the known species diversity of Archaea by ~48.6%. The structures and potential functions of the archaeal communities are strongly influenced by temperature and pH, with high-temperature acidic and alkaline springs favoring archaeal abundance over Bacteria. Genome-resolved metagenomics and metatranscriptomics provide insights into the potential ecological niches of these Archaea and their potential roles in carbon, sulfur, nitrogen, and hydrogen metabolism. Furthermore, our findings illustrate the interplay of competition and cooperation among Archaea in biogeochemical cycles, possibly arising from overlapping functional niches and metabolic handoffs. Taken together, our study expands the genomic diversity of Archaea inhabiting geothermal springs and provides a foundation for more incisive study of biogeochemical processes mediated by Archaea in geothermal ecosystems. Here, Qi et al. assembled ~3000 archaeal genomes from hot springs, capturing temporal dynamics and environmental diversity, and systematically explored functional niches and metabolic handoffs, shedding light on Archaea's role in biogeochemical cycling. [ABSTRACT FROM AUTHOR]

Habitat fragmentation can facilitate local adaptation of species to heterogeneous environments and affect population demographic history. To understand the factors influencing evolutionary dynamics, such as climatic fluctuations and complex geomorphological features, we used 18 chloroplast microsatellites, 15 nuclear microsatellites, three chloroplast fragments, and two nuclear regions to explore the genetic structure and phylogeographical history of Pseudotaxus chienii. Furthermore, its current and past distributions were constructed based on ecological niche modelling. Moderate to high levels of genetic diversity were found at the species level. Precipitation was a decisive factor influencing the genetic structure of P. chienii. In addition, local adaptation to heterogeneous environments also contributed to maintain the fragmented distribution. Finally, incomplete lineage sorting led to the cyto-nuclear discordance. Overall, we show that pre-Quaternary and Quaternary climatic fluctuations and restricted gene flow exerted significant effects on the formation and maintenance of the fragmented distribution of P. chienii. The study provides new insights into the evolutionary history of plants in subtropical China. [ABSTRACT FROM AUTHOR]

Hylurgus ligniperda (Fabricius), a significant quarantine pest, has recently invaded China, marking a new spread outside its known global distribution. This study aims to clarify the invasion and colonization mechanisms of H. ligniperda in Shandong Province, a primary colonization site. This study employed sampling surveys and analysis of damaged wood, discovering that the wood-boring insects sharing the same host as H. ligniperda mainly include Cryphalus sp., Arhopalus rusticus, and Shirahoshizo sp. Through ecological niche theory, the study analyzed the ecological niche relationships between H. ligniperda and these three wood-boring insects, from the perspectives of temporal and spatial resource utilization. The results reveal that these insects could cause damage to P. thunbergii trees at different health levels, with H. ligniperda being the most destructive. The ecological niches of insect populations varied significantly by tree vigor and height. Cryphalus sp. occupied the entire trunk, whereas A. rusticus and Shirahoshizo sp. were concentrated in the lower-middle trunk and the root section up to a depth of 1 m. Notably, H. ligniperda primarily targeted tree roots. Due to the differences in spatial distribution, there was no intense competition between H. ligniperda and other wood-boring insects. With a decline in the health of the host tree, Cryphalus sp. ascended the trunk, whereas H. ligniperda spread deeper into the roots and A. rusticus moved towards the base of the trunk and the top of the roots. Shirahoshizo sp. showed a less defined distribution pattern. Therefore, H. ligniperda was more dominant during the later stage of damage. The position occupied by each insect on the trunk was relatively stable, and the ecological niche overlap value with H. ligniperda was low in terms of temporal resources. Therefore, H. ligniperda and other stem-boring pests exhibit coexisting populations mainly through the allocation and utilization of spatial resources, eventually promoting the successful colonization of H. ligniperda. [ABSTRACT FROM AUTHOR]

The Qinling Mountains in East Asia serve as the geographical boundary between the north and south of China and are also indicative of climatic differences, resulting in rich ecological and species diversity. However, few studies have focused on the responses of plants to geological and climatic changes in the Qinling Mountains and adjacent regions. Therefore, we investigated the evolutionary origins and phylogenetic relationships of three Pedicularis species in there to provide molecular evidence for the origin and evolution of plant species. Ecological niche modeling was used to predict the geographic distributions of three Pedicularis species during the last interglacial period, the last glacial maximum period, and current and future periods, respectively. Furthermore, the distribution patterns of climate fluctuations and the niche dynamics framework were used to assess the equivalence or difference of niches among three Pedicularis species. The results revealed that the divergence of three Pedicularis species took place in the Miocene and Holocene periods, which was significantly associated with the large-scale uplifts of the Qinling Mountains and adjacent regions. In addition, the geographic distributions of three Pedicularis species have undergone a northward migration from the past to the future. The most important environmental variables affecting the geographic distributions of species were the mean diurnal range and annual mean temperature range. The niche divergence analysis suggested that the three Pedicularis species have similar ecological niches. Among them, P. giraldiana showed the highest niche breadth, covering nearly all of the climatic niche spaces of P. dissecta and P. bicolor. In summary, this study provides novel insights into the divergence and origins of three Pedicularis species and their responses to climate and geological changes in the Qinling Mountains and adjacent regions. The findings have also provided new perspectives for the conservation and management of Pedicularis species. [ABSTRACT FROM AUTHOR]

In recent decades, ecological niche models (ENMs) have been widely used to predict suitable habitats for species. However, for invasive organisms, the prediction accuracy is unclear. In this study, we employed the most widely used maximum entropy (MaxEnt) model and ensemble model (EM) Biomod2 and verified the practical effectiveness of the ENM in predicting the distribution areas of invasive insects based on the true occurrence of Hyphantria cunea in China. The results showed that when only limited data of invasive areas were used, the two ENMs could not effectively predict the distribution of suitable habitats of H. cunea, although the use of global data can greatly improve the prediction accuracy of ENMs. When analyzing the same data, Biomod2's prediction accuracy was significantly better than that of MaxEnt. For long‐term predictions, the area of suitable habitat predicted by the ENMs was much greater than the occurrence area; for short‐term predictions, the accuracy of the predicted area was significantly improved. Under the current conditions, the area of suitable habitat for H. cunea in China is 118 × 104 km2, of which 59.32% is moderately or highly suitable habitat. Future climate change could significantly increase the suitable habitat area of H. cunea in China, and the predicted area of suitable habitats in all climate scenarios exceeded 355 × 104 km2, accounting for 36.98% of the total land area in China. This study demonstrates the use of ENMs to study invasive insects and provides a reference for the management of H. cunea in China. [ABSTRACT FROM AUTHOR]

The rape stem weevil (Ceutorhynchus asper Roel.) and its close relatives primarily breed on cruciferous plants and cause severe damage to rapeseed production. However, their genetic and molecular information is still scarce. Here, we generated mitogenomes for both C. asper and Ceutorhynchus albosuturalis. The lengths of the 2 mitochondrial genomes are 14,207 bp (C. asper) and 15,373 bp (C. albosuturalis), and both weevils exhibit identical numbers of protein-coding genes with the absence of trnI. A + T contents for both mitogenomes are high (80% and 79.9%, respectively). Haplotype and genetic distance analyses showed that the genetic differentiation of C. asper populations in northwestern China is low. Based on 5 datasets from mitogenomes, phylogenetic analyses with maximum-likelihood and Bayesian methods show that both species (C. asper and C. albosuturalis) fall in the CCCMS clade (Curculioninae, Conoderinae, Cossoninae, Molytinae, and Scolytinae) of Curculionidae and belong to clades H and I of the genus Ceutorhynchus , respectively. Larvae of the clade H weevils mainly are borers in petioles or stems of cruciferous plants, while larvae of the clade I weevils mainly inhabit the fruits of the same plants, suggesting that ecological niche specialization can play a critical role in the diversification of Ceutorhynchus species. This study generates baseline molecular and genetic information for future research of Ceutorhynchus -related taxa and provides insights into the phylogeny and evolution of Curculionidae. [ABSTRACT FROM AUTHOR]

Endangered species are being threatened by climate and land-use changes. However, the relative effects of climate and land-use changes on forest resident birds remain unclear. In this study, we employed an ecological niche model to forecast the potential influence of climate and land-use changes on Reeves's pheasant (Syrmaticus reevesii), while taking into account topographical limitations. We observed that climate and land-use changes would have a remarkably negative impact on Syrmaticus reevesii, and climate change would play a dominant role. Consequently, the potential distribution range of Syrmaticus reevesii would sharply decrease, and this species may face a significant risk of extinction in 2070. In addition, we found that the area change predicted by climate and land-use changes would be significantly lower inside the China Nature Reserve Network (NNR) than outside the NNR. However, less than 15% of the area suitable for Syrmaticus reevesii has been covered by NNR. Furthermore, our results showed that the response of Syrmaticus reevesii to climate and land-use changes largely depended on topographical factors, and Syrmaticus reevesii would face greater impacts from climate and land-use changes under topographical limitations. Taken together, we highlight that it is imperative to adjust and develop nature reserve networks and conservation strategies to cope with rapid global environmental change. [ABSTRACT FROM AUTHOR]

Pinus massoniana Lamb. is one of the main timber tree species. There is a large artificial planting area in South China, and this tree has important economic and ecological value. In this research, we built a comprehensive habitat suitability model based on 115 current data and 22 environmental variables to analyze the potential suitable habitat distribution of this species. Future climate change scenarios were defined as four shared socioeconomic pathways (SSPs): SSP 1–2.6, SSP 2–4.5, SSP 3–7.0, SSP 5–8.5) and four periods (including 2021–2040, 2041–2060, 2061–2080, and 2081–2100) based on nine global circulation model datasets. To fully consider the potential distribution of P. massoniana under specific climate change conditions and soil conditions, we constructed an ensemble model using four commonly used model algorithms. The results indicated that the current suitable habitat for P. massoniana covers approximately 1.10 × 106 km2 in southeastern China. In the future, the model results showed that under different climate change scenarios and at different times, the change in suitable habitat for P. massoniana varied; moreover, under moderate climate change scenarios, the average temperature decreased by less than 3 °C and the suitable habitat area decreased slightly, with an area larger than 0.95 × 106 km2. However, under intense warming scenarios, for which the average temperature increased above 3 °C, the suitable habitat for P. massoniana decreased. In the most severe warming scenario, the suitable habitat area for P. massoniana was reduced to 44% of the base climate conditions with severe habitat fragmentation, which should be fully considered in future planting initiatives and plant protection. [ABSTRACT FROM AUTHOR]

Against the backdrop of a global malaria epidemic that remains severe, China has eradicated indigenous malaria but still has to be alert to the risk of external importation. Understanding the distribution of vectors can provide an adequate and reliable basis for the development and implementation of vector control strategies. However, with the decline of malaria prevalence in recent years, the capacity of vector monitoring and identification has been greatly weakened. Here we have used new sampling records, climatic data, and topographic data to establish ecological niche models of the three main malaria vectors in China. The model results accurately identified the current habitat suitability areas for the three species of Anopheles and revealed that in addition to precipitation and temperature as important variables affecting the distribution of Anopheles mosquitoes, topographic variables also influenced the distribution of Anopheles mosquitoes. Anopheles sinensis is the most widespread malaria vector in China, with a wide region from the northeast (Heilongjiang Province) to the southwest (Yunnan Province) suitable for its survival. Suitable habitat areas for Anopheles lesteri are concentrated in the central, eastern, and southern regions of China. The suitable habitat areas of Anopheles minimus are the smallest and are only distributed in the border provinces of southern China. On this basis, we further assessed the seasonal variation in habitat suitability areas for these three major malaria vectors in China. The results of this study provide new and more detailed evidence for vector monitoring. In this new era of imported malaria prevention in China, regular reassessment of the risk of vector transmission is recommended. Author summary: Malaria, as one of the most important insect-borne infectious diseases in tropical and subtropical regions, poses a serious disease burden worldwide. Malaria has been prevalent in China for more than 4,000 years, seriously endangering the health of the Chinese people and restricting socio-economic development. Nowadays, there are three major species of malaria transmission in China, Anopheles sinensis, Anopheles lesteri, and Anopheles minimus. Due to vector control and climate change in recent years, the distribution range of these Anopheles mosquitoes has changed. Here, we applied an ecological niche model to simulate the potential distribution as well as seasonal variation of three species of Anopheles and to identify the factors affecting their survival. The results revealed that precipitation, temperature, and topographic variables were important influences on the distribution of Anopheles mosquitoes. A wide region from the northeast (Heilongjiang Province) to the southwest (Yunnan Province) is suitable for An. sinensis. Suitable habitat areas for An. lesteri are concentrated in the central, eastern, and southern regions of China. The suitable habitat areas of An. minimus are the smallest, which are only distributed in the border provinces of southern China. This study provides new information for policymakers to develop vector control measures. [ABSTRACT FROM AUTHOR]

In recent years, buckwheat (Fagopyrum spp.) is being increasingly damaged by the Siberian tortoise beetle (Rhinoncus sibiricus Faust). Adults and nymphs feed on leaf tissues and caulicles, thus damaging its stems and leaves. In this study, we investigated the habits, distribution, and environmental impact of R. sibiricus using MaxEnt, an ecological niche model. Geographic information about the infestation site from previous field surveys and climatic data from 2013 to 2018 were organized and optimized using R. The impact factors were calculated using MaxEnt software. The results indicate that population fluctuations in R. sibiricus are related to changes in temperature, humidity, and their spatial distribution. Under current climatic conditions, R. sibiricus is mainly distributed in northern China, with sporadic distribution in south–western China. The values for a survival probability threshold > 0.3 were: precipitation during the wettest month (bio13), 70.31–137.56 mm; mean temperature of the coldest quarter (bio11), -15.00–0.85°C; mean temperature of the warmest quarter (bio10), 11.88–23.16°C; precipitation during the coldest quarter (biol9), 0–24.39 mm. The main factors contributing > 70% to the models were precipitation during the wettest month and coldest quarter, and mean temperature during the warmest and coldest quarters. Under both future climate models, the center of the fitness zone moves northward. Our results will be useful in guiding administrative decisions and support farmers interested in establishing control and management strategies for R. sibiricus. This study could also serve as a reference for future research on other invasive pests. [ABSTRACT FROM AUTHOR]

A new erinaceine, Sonidolestes wendusui gen. et sp. nov., from the Early Miocene of Inner Mongolia in China, is described here. The tooth morphology of this new taxon is quite unique. Especially, the enlarged p4 has a regressed paraconid and lacks the metaconid and the paralophid, unlike any known member of the Erinaceinae. Sonidolestes wendusui probably feeds on snails or coleopteran insects. The new erinaceine demonstrates the experimentation of members of the Asian Erinaceinae with different food and ecological niches. [ABSTRACT FROM AUTHOR]

The ecological niche gradient is an important determinant of microbial community structure. In this paper, we studied variation in rhizosphere bacterial diversity and community composition along an ecological niche gradient. We used the high-throughput sequencing of 16S rRNA genes to study changes in the rhizosphere soil microbial communities of six grass and four shrub species during the secondary succession of abandoned farmland on the Loess Plateau of China. A structural equation model (SEM) was employed to disentangle the relative contribution of ecological niche and soil properties to bacterial diversity and community composition. Proteobacteria, Acidobacteria, and Actinobacteria were the dominant phyla of rhizosphere bacteria in all samples. During the dynamics of the plant niche from low to high, bacterial community composition transitioned from Actinobacteria + Acidobacteria to Proteobacteria + Bacteroidetes higher abundance. Moreover, the bacterial diversity and species richness changed with an increasing niche gradient, showing a clear differentiation in the rhizosphere bacterial community of grassland and shrubland. Further, diversity and species richness decreased from the middle niche of B. ischaemum to the poles, indicating that the succession process had not yet reached the climax community stage. Community assembly analysis suggested that the stochastic process gradually strengthened along the increasing ecological niche gradient, especially the drift effect. Furthermore, SEM analysis showed that the ecological niche had significant negative effects on soil properties and bacterial richness, while the effects on bacterial diversity and the stochastic processes of community assembly were weakened and insignificant. Altogether, our findings suggest that the complex interaction of the ecological niche with bacterial diversity and composition was determined by soil properties. Further, bacterial diversity was not necessarily higher with increasing ecological niche gradients. [ABSTRACT FROM AUTHOR]

The plant pathogenic fungus Cytospora is notoriously known for causing woody plant canker diseases, resulting in substantial economic losses to biological forests and fruit trees worldwide. Despite their strong negative ecological impact, the existing and prospective distribution patterns of these plant pathogens in China, according to climate change, have received little attention. In this study, we chose three widely dispersed and seriously damaging species, namely, Cytospora chrysosperma, Cytospora mali, and Cytospora nivea, which are the most common species that damage the Juglans regia, Malus domestica, Eucalyptus, Pyrus sinkiangensis, Populus spp., and Salix spp. in China. We utilized ecological niche modeling to forecast their regional distribution in China under four climate change scenarios (present, SSP 126, SSP 370, and SSP 585). The results show that temperature-related climate factors limit the current distribution ranges of the three species. Currently, the three studied species are highly suitable for northeast, northwest, north, and southwest China. Under future climate scenarios, the distribution ranges of the three species are projected to increase, and the centers of the adequate distribution areas of the three species are expected to shift to high-latitude regions. The three species coexist in China, primarily in the northwest and north regions. The ecological niches of C. chrysosperma and C. nivea are more similar. The distribution range of C. mali can reach the warmer and wetter eastern region, whereas C. chrysosperma and C. nivea are primarily found in drought-prone areas with little rainfall. Our findings can help farmers and planners develop methods to avoid the spread of Cytospora spp. and calculate the costs of applying pesticides to reduce contamination and boost yields. [ABSTRACT FROM AUTHOR]

China has the most numerous Danxia and Karst landscapes, which serve as special terrestrial islands harboring ample endemic species, though how did these endemic species spread among those isolated sites is still an unresolved issue. To address this question, we explored the phylogeographical structure and demographic history of Firmiana danxiaensis, a tree species endemic to Danxia and Karst landscapes. We collected 295 samples (28 populations) of F. danxiaensis. Plastid genomes were assembled for 25 representative samples. Sanger sequencing of four plastid regions and restriction‐site‐associated DNA sequencing were performed on the 28 populations. The phylogenetic tree constructed from plastid genomes and restriction site‐associated DNA sequencing (RAD‐seq) data supported that F. danxiaensis originated from Mount Danxia and Nanxiong Basin, spread to Karst landscapes near Yingde City, and then back to Danxia Mountain and the Nanxiong Basin. In the Nanxiong Basin, the latter arrivals captured the plastid of the former. Population analyses revealed strong population structure among and within Danxia and Karst landscapes, possibly due to low seed and pollen dispersal abilities of the species. The demographic and ecological niche modeling approaches suggested that F. danxiaensis have widely occurred in the southeast of China during the last glacial period, and later retreated to the cliffs of Danxia and Karst landscapes due to temperature rising and competition failure. The declining of the effective population size of the species throughout the postglacial period suggested that global warming, agriculture, and industrial civilizations could have affected the survival of this species, and more measures should be taken to conserve these species. [ABSTRACT FROM AUTHOR]

Clear species boundaries are crucial for plans and actions on biodiversity conservation. However, morphological similarities among allied species can result in taxonomic difficulties, thus impeding conservation efforts. In China, Cinnamomum japonicumSiebold is a well‐known endangered plant, yet suffers from longstanding taxonomic issues. Here, we explicitly evaluate whether C. japonicum, C. chenii, and C. chekiangense are the same phylogenetic species on the basis of a multi‐individual sampling strategy. We identified three sets of low‐copy orthologous genes from 19 Lauraceae taxa for phylogenetic inferences. Both the concatenation and coalescent‐based phylogenies supported that C. chenii individuals were embedded in the C. japonicum clade, indicating these two taxa are conspecific. Meanwhile, C. chekiangense accessions formed a monophyly which was not sister to C. japonicum. This result, together with the morphological differences that the leaves of C. japonicum are glabrous with a faveolate pattern of venation while those of C. chekiangense have trichomes and inevident lateral veins, led us to consider both as two distinct species. Based on 17 728 neutral single nucleotide polymorphisms (SNPs), the ADMIXTURE analysis suggested that the Chinese C. japonicum populations in Zhoushan Archipelago (=C. chenii) were genetically differentiated from the Japanese and Korean ones. Furthermore, ecological niche modeling predicted that the present distribution area of Chinese C. japonicum is likely to be unsuitable under global warming scenarios. Together with its limited distribution and genetic uniqueness, we recommend that Chinese C. japonicum deserves conservation priorities. [ABSTRACT FROM AUTHOR]

Functional traits play an important role in studying the functional niche in plant communities. However, it remains unclear whether the functional niches of typical forest plant communities in different climatic regions based on functional traits are consistent. Here, we present data for 215 woody species, encompassing 11 functional traits related to three fundamental niche dimensions (leaf economy, mechanical support, and reproductive phenology). These data were collected from forests across four climatic zones in China (tropical, subtropical, warmtemperate, and cold-temperate) or sourced from the literature. We calculated the functional niche hypervolume, representing the range of changes in the multidimensional functional niche. This metric quantifies how many functional niche spaces are occupied by existing plants in the community. Subsequently, we analyzed differences in functional niche hypervolume and their associated environmental factors across different types of forest vegetation. The results indicate that the functional niche hypervolume and the degree of forest vegetation overlap decrease with increasing latitude (e.g., from tropical rainforest to cold temperate coniferous forest). The total explanatory power of both climate and soil factors on the variation in functional niche hypervolume was 50%, with climate factors exhibiting a higher explanatory power than soil factors. Functional niche hypervolume is positively correlated with climate factors (annual mean temperature and annual precipitation) and negatively correlated with soil factors (soil pH, soil organic matter content, soil total nitrogen content, and soil total phosphorus content). Among these factors, annual mean temperature, soil pH, and soil total nitrogen content most significantly affect the difference in functional niche hypervolume among forest vegetation. Our study emphasizes the significant variation in the functional niche hypervolume among typical forest vegetation in China. [ABSTRACT FROM AUTHOR]

Simple Summary: Eutrophication is a significant challenge for urban aquatic ecosystems. Many studies suggest the negative effect of eutrophication on the diversity of planktonic communities; however, we still know little about the characteristics of aquatic functional groups in relation to varying degrees of eutrophication in urban river systems. The effects of urban river eutrophication on rotifer communities are investigated using an annual field survey of the Jinan section of the Xiaoqing River, a typical urban river in northern China. We observed that the functional diversity of the rotifer community decreased with the degree of eutrophication. Functional diversity exhibited an extremely low level across functional groups. These findings indicate that eutrophication led to the homogenization of rotifer communities, which can be attributed to the widely distributed species complementing the ecological niche space. Our findings provide valuable information on the conservation of the urban river under the threat of eutrophication caused by high-intensity human activities. Rapid urbanization has triggered nutrient loading, which will inevitably lead to the eutrophication of water bodies and further affect the structure of aquatic populations. At present, eutrophication is a significant challenge for urban aquatic ecosystems. However, we still know little about the correlation between eutrophication in urban rivers and the composition of aquatic functional groups. The effects of urban river eutrophication on rotifer communities were investigated using an annual field survey of the Jinan section of the Xiaoqing River, a typical urban river in northern China. Using functional diversity (FD) and beta diversity, the spatiotemporal variation of the aquatic biological functional groups regime along stretches subject to different eutrophication was investigated. The functional evenness (FEve) and functional divergence (FDiv) decreased significantly with the increment of the trophic level index. Functional diversity exhibits an extremely low level across functional groups, with the richness difference (RichDiff) being an important component. The results indicate that eutrophication led to the homogenization of rotifer communities. This can be attributed to the functional homogenization of the rotifer community in the Jinan section of the Xiaoqing River. The observed homogenization may be due to widely distributed species complementing the ecological niche space. Our findings provide valuable information on the conservation of the urban river under the threat of eutrophication caused by high-intensity human activities. [ABSTRACT FROM AUTHOR]

Simple Summary: Northwest China is characterized by unique geological and historical dynamics and endemic biota, but the joint influence of geography and past climate changes on the evolutionary history of endemic animals is poorly understood. We used two mtDNA genes (ND4 and Cytb) and ecological niche modeling (ENM) to explore how the Quaternary climatic fluctuations and complex geography in Northwest China have shaped genetic diversity, genetic structure, and demographic history of the Alashan pit viper (Gloydius cognatus). Our results clearly show that the lineage diversification of G. cognatus is related to the expansions of deserts and/or the early Pleistocene integration of the Yellow River. The strong spatial genetic structure fits an isolation-by-distance model. The signature of demographic and range contractions during the last glacial maximum (LGM) is rejected by both mitochondrial evidence and ENM. In addition, the suitable habitat of G. cognatus is predicted to be decreased in the future, suggesting that conservation and management of evolutionary significant units (ESUs) should be a priority. Our findings provide the first insights on the evolutionary history of G. cognatus in arid Northwest China and adjacent areas throughout the Quaternary. The joint impacts of historical geological events and Quaternary climatic oscillations in Northwest China on species evolution have been examined extensively in plant under a phylogeographic perspective. However, animal phylogeographic analyses in this region are still limited. The Alashan pit viper, Gloydius cognatus, occurs primarily in arid Northwest China and adjacent areas. Based on variation at two mtDNA genes (ND4 and Cytb) in 27 individuals representing 24 populations, the spatial genetic structure and demographic history of G. cognatus were examined across its geographic range. Phylogenetic analyses revealed two well-supported allopatric clades (each with two distinct subclades/lineages), distributed across the southern (Qaidam Basin, Lanzhou Basin, and Zoige Basin [S1]; Loess Plateau [S2]) and northern (Ily Basin [N1]; Junggar Basin and Mongolian Plateau [N2]) regions. AMOVA analysis demonstrated that over 76% of the observed genetic variation was related to these lineage splits, indicating substantial genetic differentiation among the four lineages. A strong pattern of isolation-by-distance across the sampling populations suggested that geographic distance principally shaped the genetic structure. The four lineages diverged by 0.9–2.2% for the concatenated data, which were estimated to have coalesced ~1.17 million years ago (Mya), suggesting that the expansions of the Badain Jaran, Tengger, and Mu Us deserts during the Xixiabangma glaciation likely interrupted gene flow and triggered the observed divergence in the southern and northern regions. Subsequently, the early Pleistocene integration of the Yellow River and associated deserts expansion promoted the differentiation of S1 and S2 lineages (~0.9 Mya). Both mitochondrial evidence and ecological niche modeling (ENM) reject the signature of demographic and range contractions during the LGM for G. cognatus. In addition, ENM predicts that the suitable habitat of G. cognatus will contract in the future. As such, the conservation and management of ESUs should be a priority. Our findings provide the first insights on the lineage diversification and population dynamics of the Alashan pit viper in relation to geological history and Pleistocene climatic oscillations in arid Northwest China. [ABSTRACT FROM AUTHOR]

Aim: Research on population genetic patterns and potential distribution dynamics can provide insights into the development of pest management strategies. Herein, we integrated population genetic analyses with the climatic niche approach to investigate spatial population genetic variations and potential geographical distribution (PGD) of the herbivorous pest Phytomyza horticola. We also analysed its population response patterns to both late Pleistocene climatic events and future climate change. Location: China. Methods: We analysed the patterns of genetic diversity distribution in 29 populations from 19 regions across China using three mitochondrial (COI, COII and Cytb) genes as markers. We estimated demographic histories using neutrality tests, mismatch distributions and Bayesian skyline plots. Changes in PGD were assessed using an ecological niche model. Results: High genetic diversity was found in most populations, and the northern population exhibited higher haplotype diversity. The population genetic structure included the Tibet lineage and a large lineage comprising the remaining populations. Demographic analyses indicated that rapid population expansion occurred during the cold Last Glacial Maximum. In addition, our projections suggested that P. horticola currently has a vast PGD in China, for which the human influence index was the strongest variable. Large areas of cold northern regions were highly suitable for its survival. Under future global warming, highly suitable habitats will shift towards the higher latitudes. Main conclusions: P. horticola is widely distributed across varied environments, which may be attributed to its high degree of genetic variation. Human activities likely facilitated the current PGD and the frequent gene flow that homogenized differentiation among most populations. In addition, P. horticola exhibits strong adaptability to cold climates and environments from the past to the future. Considering future climatic changes, prevention and control should focus on high‐latitude regions, and vigilance regarding human‐mediated pest dispersals and outbreaks should be maintained. [ABSTRACT FROM AUTHOR]

Disjunct distribution is a key issue in biogeography and ecology, but it is often difficult to determine the relative roles of dispersal vs. vicariance in disjunctions. We studied the phylogeographic pattern of the monotypic Conandron ramondioides (Gesneriaceae), which shows Sino‐Japanese disjunctions, with ddRAD sequencing based on a comprehensive sampling of 11 populations from mainland China, Taiwan Island, and Japan. We found a very high degree of genetic differentiation among these three regions, with very limited gene flow and a clear Isolation by Distance pattern. Mainland China and Japan clades diverged first from a widespread ancestral population in the middle Miocene, followed by a later divergence between mainland China and Taiwan Island clades in the early Pliocene. Three current groups have survived in various glacial refugia during the Last Glacial Maximum, and experienced contraction and/or bottlenecks since their divergence during Quaternary glacial cycles, with strong niche divergence between mainland China + Japan and Taiwan Island ranges. Thus, we verified a predominant role of vicariance in the current disjunction of the monotypic genus Conandron. The sharp phylogenetic separation, ecological niche divergence among these three groups, and the great number of private alleles in all populations sampled indicated a considerable time of independent evolution, and suggests the need for a taxonomic survey to detect potentially overlooked taxa. [ABSTRACT FROM AUTHOR]

Glyptostrobus pensilis (Cupressaceae) is the only surviving species of the genus Glyptostrobus. Although the species is widely cultivated throughout China, in the wild it only occurs as small stands in southeastern China, central Laos, and southern Vietnam. However, its low genetic variability, lack of recruitment, and the progressive destruction of its habitat caused by humans, have meant that the populations are showing a clear declining trend and the species as a whole is threatened. Ecological niche modeling is used here to study the present potential distribution, as well as in the future (2061–2080) using several global circulation models under two of the shared socioeconomic pathways (SSP 126 and SSP 585) that are being used to produce the IPCC Sixth Assessment Report. The current potential area of G. pensilis is of 1,452,481 km2 with the areas of greatest probability of presence located in southeastern China. This potential area is reduced for the future according to most models, with greater losses for the SSP 585 scenario. Between 6.9 and 31.3% of all wild populations of G. pensilis would be outside potential areas (including the Lao populations, which harbor the highest levels of genetic variability). Conservation measures include the expansion of the current network of protected areas (since over 90% of wild populations do not occur within them), the development of propagation techniques, and the carrying out of translocation activities that should require international collaboration among the countries in which the species is found. With the current knowledge, we have reassessed the threat status of the species under the IUCN criteria, downgrading it from CR to EN both for China and at global level. [ABSTRACT FROM AUTHOR]

Decreasing water volume and increasing pollutants in wetlands pose challenges to aquatic life. While environmental flow regulation is widely applied to enhance aquatic habitats, its effectiveness needs to be evaluated. In this study, a hydrodynamic-water quality model was used to simulate the fields of flow, temperature, and pollutants. The Ecological Niche Modeling at the MetaLand EcologyLab (ENMTML) was utilized to evaluate the area of suitable habitats for aquatic organisms under both environmental flow regulation and no environmental flow regulation conditions. The typical Baiyangdian Wetland in northern China was taken as the study area, and the important economic fish, Cyprinus carpio, served as the indicator of aquatic species. The effectiveness of environmental flow regulation was evaluated from December 1, 2017, to June 30, 2018. The results indicated that the variables of water depth, dissolved oxygen (DO), ammonia nitrogen (NH4+-N) and Chlorophyll a (Chla) were the major environmental factors determining the variability of the suitable habitat area for Cyprinus carpio. The environmental flow regulation capacity of the Baiyangdian Wetland was 2.6 × 108 m3, which produced a suitable habitat area of 135.538 km2 at the end of the water supply period. Compared with the no environmental flow regulation condition, the highly and moderately suitable habitat areas for Cyprinus carpio were enlarged by 56.30 km2 and 34.11 km2, respectively. The outcome provides not only a basic reference for wetland management, but also a scientific perspective for understanding the impact of environmental flow regulation on aquatic organisms. The proposed method demonstrates the important potential of evaluating the effectiveness of environmental flow regulation on aquatic organisms in wetlands. [ABSTRACT FROM AUTHOR]

With its nearly 200 species, the Mammillaria genus is the most species-rich within the Cactaceae family, yet surprisingly, few of its chloroplast genomes have been studied. We focused on the species Mammillaria elongata DC. 1828, a petite cactus native to Mexico and favored by horticulturists, yet whose phylogenetic relationships remain uncertain due to a lack of genomic data. We extracted the DNA from a sample obtained in China, sequenced it using the NovaSeq 6000 platform, and assembled the chloroplast genome using GetOrganelle software. Our assembly resulted in a chloroplast genome of 110,981 base pairs with an overall GC content of 36.28%, which included 100 genes (95 unique). Notably, several protein-coding genes were absent. Phylogenetic analysis using 59 shared genes across nine Mammillaria species and one Obregonia species revealed that M. elongata and M. gracilis are closely related, suggesting a recent common ancestor and possible shared evolutionary pressures or ecological niches. This study provides crucial genomic data for M. elongata and hints at intriguing phylogenetic relationships within the Mammillaria genus. [ABSTRACT FROM AUTHOR]

Two thrips, Megalurothrips usitatus (Bagnall) and Frankliniella intonsa (Trybom) are major pests of cowpea in South China. To realistically compare the growth, development and reproductive characteristics of these two thrips species, we compared their age-stage, two-sex life tables on cowpea pods under summer and winter natural environmental regimes. The results showed that the total preadult period of M. usitatus was 8.09 days, which was significantly longer than that of F. intonsa (7.06 days), while the adult female longevity of M. usitatus (21.14 days) was significantly shorter than that of F. intonsa (25.77 days). Significant differences were showed in male adult longevity (10.68 days for F. intonsa and 16.95 days for M. usitatus) and the female ratio of offspring (0.67 for F. intonsa and 0.51 for M. usitatus), and the total preadult period of M. usitatus (16.20 days) was significantly longer than that of F. intonsa (13.66 days) in the winter regime. The net reproductive rate (summer: R 0 = 85.62, winter: R 0 = 105.22), intrinsic rate of increase (summer: r = 0.3020 day−1, winter: r = 0.2115 day−1), finite rate of increase (summer: λ = 1.3526 day−1, winter: λ = 1.2356 day−1) and gross reproduction rate (summer: GRR = 139.34, winter: GRR = 159.88) of F. intonsa were higher than those of M. usitatus (summer: R 0 = 82.91, r = 0.2741, λ = 1.3155, GRR = 135.71; winter: R 0 = 80.62, r = 0.1672, λ = 1.1820, GRR = 131.26), and the mean generation times (summer: T = 14.73 days, winter: T = 22.01 days) of F. intonsa were significantly shorter than those of M. usitatus (summer: T = 16.11 days, winter: T = 26.25 days). These results may contribute to a better understanding of the bioecology of different thrips species, especially the interspecific competition between two economically important cowpea thrips with the same ecological niche in a changing environment. [ABSTRACT FROM AUTHOR]

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Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biodiversity patterns of microscopic organisms, such as bdelloid rotifers are generally lacking. In this study, bdelloid rotifers from moss and leaf litter habitats were collected from a small area of 14 square kilometres in Changde City, Southern China. Species diversity and habitat preferences were examined using morphological methods. A total of 64 morphological species (including subspecies) were identified, accounting for 65.3% of the bdelloid rotifers recorded in China. The DNA taxonomy of rotifers (Rotaria sordida with no preference and leaf litter-preferring Adineta beysunae) with high Indicator Values (IndVal) identified eight and two cryptic species, respectively, in Changde. The species richness of bdelloid rotifers was significantly (Student's t test, p < 0.01) lower in moss than in leaf litter, and the bdelloid rotifer communities differed significantly (analysis of group similarities, p < 0.01) between moss and leaf litter habitats. Indicator species analysis revealed that A. beysunae had a strong habitat preference (IndVal, p < 0.01). Additionally, Pearson's phi correlation analysis indicated that the cryptic species within the species complex of R. sordida had a weak habitat preference (phi, p < 0.05). Bayesian phylogenetic trees and genetic diversity analyses of R. sordida and A. beysunae indicated that genetic diversity differed between different habitats. These findings indicate high bdelloid rotifer biodiversity with strong habitat preferences between moss and leaf litter habitats at the morphological taxonomy level but weak habitat preferences at the genetic taxonomy level, implying that bdelloid species can be used as indicators of heterogeneous habitats and provide an ecological basis for the discovery and conservation of bdelloid rotifer species diversity. [ABSTRACT FROM AUTHOR]

Revealing the regional distribution and diversity of fungal sub-communities under different land management practices is essential to conserve biodiversity and predict microbial change trends. In this study, a total of 19 tilled and 25 untilled soil samples across different land-use types were collected from subtropical China to investigate the differences between the spatial distribution patterns, diversity, and community assembly of fungal sub-communities using high-throughput sequencing technology. Our results found that anthropogenic disturbances significantly reduced the diversity of abundant taxa but significantly increased the diversity of rare taxa, suggesting that the small-scale intensive management of land by individual farmers is beneficial for fungal diversity, especially for the conservation of rare taxa. Abundant, intermediate, and rare fungal sub-communities were significantly different in tilled and untilled soils. Anthropogenic disturbances both enhanced the homogenization of fungal communities and decreased the spatial-distance–decay relationship of fungal sub-communities in tilled soils. Based on the null model approach, the changes in the assembly processes of the fungal sub-communities in tilled soils were found to shift consistently to stochastic processes, possibly as a result of the significant changes in the diversity of those fungal sub-communities and associated ecological niches in different land-use types. Our results provide support for the theoretical contention that fungal sub-communities are changed by different land management practices and open the way to the possibility of predicting those changes. [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]

Invasive alien ant species pose serious threats to agricultural production, ecosystems, and human health in China. Solenopsis invicta Buren is the most destructive and aggressive invasive alien ant in China, causing serious agricultural and urban economic losses and public health concerns. Estimating its spatial distribution and ecological niche in China is crucial for S. invicta prevention and control. Based on 4195 occurrence records (4096 invasive occurrence records and 99 native occurrence records) and 10 environmental variables, we estimated the potential suitable area and ecological niche of S. invicta in China using the ensemble model and 'ecospat' package in R language. The mean AUC, KAPPA, and TSS values of the ensemble model were 0.989, 0.901, and 0.901, respectively, indicating that the ensemble model was better than the single-species distribution model for the simulation. Temperature, precipitation, and human factors are important variables that influence the distribution of S. invicta. Our results showed that the ecological niche similarity and equivalency test results showed that the ecological niches between native areas and China were not equivalent (D = 0.46, p = 0.001), but were more similar than would be expected by chance (p = 0.003). Under current climatic conditions, the total potential suitable area for S. invicta is 192.89 × 104 km2 in China, accounting for 20.09% of the land area in China; this land is mainly distributed in Hainan, Taiwan, Guangdong, Guangxi, Fujian, Zhejiang, Jiangsu, Anhui, Hubei, Hunan, Jiangxi, Guizhou, Yunnan, Chongqing, Sichuan, and Henan. Under future climatic conditions, the potential suitable areas of S. invicta will further increase, while the highly suitable areas will shift to higher latitudes. We suggest that early warning and monitoring of S. invicta in the central and northern areas of China should be strengthened to prevent its further spread. [ABSTRACT FROM AUTHOR]

Taking the core zone of Yancheng National Nature Reserve (YNNR) as an example, the landscape habitat stability was analyzed by Ecological Niche models from 1983 to 2021. The evaluation index system of landscape habitat stability was constructed from the 'State' and 'Trend' dimensions by using the 'State-Pressure-Response' model. The landscape structure changed significantly, showing a trend of continuous expansion of Phragmites australis (P. australis) marsh and Spartina alterniflora (S. alterniflora) marsh, and first increase and then decrease of Suaeda salsa (S. salsa) marsh. The niche breadth ranged from 2.4297 to 2.6187, the highest value appeared in 1992 and the lowest value was found in 2017. The niche overlap was high in different years, and there was still more than 50% overlap in the nearly 40 years span. The niche value was the highest in 1992 and the lowest in 2017, showing the trend of rising first, then falling, and then rising. The annual gradient of the ecological niche was 0.0002 in 1983-1992, -0.0058 in 1992-2017, and 0.0025 in 2017-2021. The niche expansion value showed a slow upward trend, indicating a good development trend of landscape habitat. The results can provide reference for the sustainable construction of Yancheng coastal wetlands. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidiosis is a zoonotic intestinal infectious disease caused by Cryptosporidium spp., and its transmission is highly influenced by climate factors. In the present study, the potential spatial distribution of Cryptosporidium in China was predicted based on ecological niche models for cryptosporidiosis epidemic risk warning and prevention and control. Methods: The applicability of existing Cryptosporidium presence points in ENM analysis was investigated based on data from monitoring sites in 2011–2019. Cryptosporidium occurrence data for China and neighboring countries were extracted and used to construct the ENMs, namely Maxent, Bioclim, Domain, and Garp. Models were evaluated based on Receiver Operating Characteristic curve, Kappa, and True Skill Statistic coefficients. The best model was constructed using Cryptosporidium data and climate variables during 1986‒2010, and used to analyze the effects of climate factors on Cryptosporidium distribution. The climate variables for the period 2011‒2100 were projected to the simulation results to predict the ecological adaptability and potential distribution of Cryptosporidium in future in China. Results: The Maxent model (AUC = 0.95, maximum Kappa = 0.91, maximum TSS = 1.00) fit better than the other three models and was thus considered the best ENM for predicting Cryptosporidium habitat suitability. The major suitable habitats for human-derived Cryptosporidium in China were located in some high-population density areas, especially in the middle and lower reaches of the Yangtze River, the lower reaches of the Yellow River, and the Huai and the Pearl River Basins (cloglog value of habitat suitability > 0.9). Under future climate change, non-suitable habitats for Cryptosporidium will shrink, while highly suitable habitats will expand significantly (χ2 = 76.641, P < 0.01; χ2 = 86.836, P < 0.01), and the main changes will likely be concentrated in the northeastern, southwestern, and northwestern regions. Conclusions: The Maxent model is applicable in prediction of Cryptosporidium habitat suitability and can achieve excellent simulation results. These results suggest a current high risk of transmission and significant pressure for cryptosporidiosis prevention and control in China. Against a future climate change background, Cryptosporidium may gain more suitable habitats within China. Constructing a national surveillance network could facilitate further elucidation of the epidemiological trends and transmission patterns of cryptosporidiosis, and mitigate the associated epidemic and outbreak risks. [ABSTRACT FROM AUTHOR]

Purpose: Microorganisms have a multidimensional influence on plants, and they play pivotal roles in the soil-root interface mechanism. However, little is known about microorganisms for plants in the riparian environment regarding the endosphere, rhizosphere, and bulk soil. Therefore, this study assessed rhizodeposition, the structure of bacterial communities, and the assembly processes among the endosphere, rhizosphere, and bulk soil. Methods: Salix matsudana, Taxodium distichum, Cynodon dactylon, and Hemarthria altissima were investigated in the riparian zone of the Ruxi River, China. We collected rhizospheres, bulk soil, and roots for these plants and analyzed the soil's physico-chemical properties, enzyme activities, bacterial community complexity, and assembly processes. Results: The results showed different abundant bacterial communities in the rhizosphere, bulk soils, and roots. Rhizodeposition of nitrogen and phosphorus had the greatest impact on bacterial diversity. Bacteria had more positive relationships in the endosphere than in soil compartments, indicating a relatively complex and stable community structure. The stochastic processes shape the microbial geographic variation of the endosphere, rhizosphere, and bulk soil for selected plants, with the proportional contribution in the rhizosphere and bulk soil being significantly less than that in the endosphere. Different microhabitats, via the assembly process, shape bacterial community structures. Conclusions: We discovered that the bacterial community in the endosphere was less affected by environmental factors and more stable than the bacterial community in the soil compartment. This will help us find the best ways to keep soil and water safe in the newly formed riparian zone and understand the ecological evolution of microbes for vegetation restoration. [ABSTRACT FROM AUTHOR]

Background: Hybridization is generally considered an important creative evolutionary force, yet this evolutionary process is still poorly characterized in karst plants. In this study, we focus on natural hybridization in yellow Camellia species, a group of habitat specialists confined to karst/non-karst habitats in southwestern China. Results: Based on population genome data obtain from double digest restriction-site associated DNA (ddRAD) sequencing, we found evidence for natural hybridization and introgression between C. micrantha and C. flavida, and specifically confirmed their hybrid population, C. "ptilosperma". Ecophysiological results suggested that extreme hydraulic traits were fixed in C. "ptilosperma", these being consistent with its distinct ecological niche, which lies outside its parental ranges. Conclusion: The identified hybridization event is expected to have played a role in generating novel variation during, in which the hybrid population displays different phenological characteristics and novel ecophysiological traits associated with the colonization of a new niche in limestone karst. [ABSTRACT FROM AUTHOR]

Determining whether the climatic ecological niche of an invasive alien plant is similar to that of the niche occupied by its native population (ecological niche conservatism) is essential for predicting the plant invasion process. Ragweed (Ambrosia artemisiifolia L.) usually poses serious threats to human health, agriculture, and ecosystems within its newly occupied range. We calculated the overlap, stability, unfilling, and expansion of ragweed's climatic ecological niche using principal component analysis and performed ecological niche hypothesis testing. The current and potential distribution of A. artemisiifolia was mapped by ecological niche models to identify areas in China with the highest potential risk of A. artemisiifolia invasion. The high ecological niche stability indicates that A. artemisiifolia is ecologically conservative during the invasion. Ecological niche expansion (expansion = 0.407) occurred only in South America. In addition, the difference between the climatic and native niches of the invasive populations is mainly the result of unpopulated niches. The ecological niche model suggests that southwest China, which has not been invaded by A. artemisiifolia, faces an elevated risk of invasion. Although A. artemisiifolia occupies a climatic niche distinct from native populations, the climatic niche of the invasive population is only a subset of the native niche. The difference in climatic conditions is the main factor leading to the ecological niche expansion of A. artemisiifolia during the invasion. Additionally, human activities play a substantial role in the expansion of A. artemisiifolia. Alterations in the A. artemisiifolia niche would help explain why this species is so invasive in China. [ABSTRACT FROM AUTHOR]

Simple Summary: Bemisia tabaci is a globally notorious agricultural pest due to its highly polyphagous characteristic, its composition as a cryptic species, and its transmission of plant viruses. The whitefly has endosymbiotic bacteria in cells inside their bodies that have strong effects on the host biology. Generally, the geographical distribution of these cryptic species and their endosymbionts' infection patterns are related to ecological factors. In this study, we determined eight cryptic species (MED, MEAM1, Asia I, Asia II 1, Asia II 2, Asia II 6, China 1, and China 6) from 29 geographical localities across China. Native cryptic species were still widespread in the Yangtze River Valley and eastern coastal areas. In addition, we found that the cryptic species distribution and their facultative endosymbionts' infection patterns were closely associated with the geographical and environmental factors, i.e., latitude and annual mean temperature. This work highlights that range expansion of invasive species and host–endosymbiont interactions need to be studied within an environmental and geographic context. The sweetpotato whitefly, Bemisia tabaci species complex, comprises at least 44 morphologically indistinguishable cryptic species, whose endosymbiont infection patterns often varied at the spatial and temporal dimension. However, the effects of ecological factors (e.g., climatic or geographical factors) on the distribution of whitefly and the infection frequencies of their endosymbionts have not been fully elucidated. We, here, analyzed the associations between ecological factors and the distribution of whitefly and their three facultative endosymbionts (Candidatus Cardinium hertigii, Candidatus Hamiltonella defensa, and Rickettsia sp.) by screening 665 individuals collected from 29 geographical localities across China. The study identified eight B. tabaci species via mitochondrial cytochrome oxidase I (mtCOI) gene sequence alignment: two invasive species, MED (66.9%) and MEAM1 (12.2%), and six native cryptic species (20.9%), which differed in distribution patterns, ecological niches, and high suitability areas. The infection frequencies of the three endosymbionts in different cryptic species were distinct and multiple infections were relatively common in B. tabaci MED populations. Furthermore, the annual mean temperature positively affected Cardinium sp. and Rickettsia sp. infection frequencies in B. tabaci MED but negatively affected the quantitative distribution of B. tabaci MED, which indicates that Cardinium sp. and Rickettsia sp. maybe play a crucial role in the thermotolerance of B. tabaci MED, although the host whitefly per se exhibits no resistance to high temperature. Our findings revealed the complex effects of ecological factors on the expansion of the invasive whitefly. [ABSTRACT FROM AUTHOR]

Only one third of the world average can be found in the per capita farmland in China. Furthermore, a large number of high-quality cultivated land has been occupied and replaced by low-quality farmland with the continuous development of urbanization in recent years. The unsuitable or uncultivable distribution of farmland in areas (such as beaches and mountains) has posed a serious threat to the national security of farmland. Great challenges have also been put the national food security in the context of emergencies, such as epidemics and disasters. It is a high demand for the high level self-sufficiency in food production under a large population during this time. In this study, a new understanding was offered to protect the farmland system, in order to change the perception from the farmland system to the cultivatable land. The ecological niche model and geographic information system (GIS) were used to measure the scale size and spatial distribution of cultivatable land, current farmland, and construction land. Firstly, the amount of cultivatable land was sufficient with the outstanding difference in spatial distribution. The cultivatable land was sufficient in the east of Chinese Heihe-Tengchongn line, where the area was approximately 2.05 times that of the current farmland. Secondly, there was the uneven quality of current farmland, where the less current farmland was distributed in the highly cultivable areas. There was an outstanding location difference in cultivatable land quality. The cultivatable land showed a hierarchical level in different areas, where the quality gradually decreased from the southeast to the northwest of China. Thirdly, there was a spatial mismatch between the cultivatable land and the current farmland. About 16.83% of the current farmland was in the unsuitable area for cultivation. The current farmland was distributed in the uncultivable areas, where the low quality of farmland led to low production in the essential goal of farmland protection, due to the mismatch between the cultivatable land and current farmland. The proposal of cultivatable land was provided the direction for the transformation of farmland protection. The "grain-land" mismatch rate of farmland also reduced resource consumption and environmental pollution. The cultivatable land grading and zoning protection were carried out to appropriately adjust the layout of current and new farmland, in order to realize the fertile land for grain use and storage. At the same time, the protection of cultivatable land can greatly contribute to the cultivatable capacity of the land, in order to avoid the encroachment and squeezing of the cultivatable land, due to urbanization. The retention of enough land can be expected to fully meet the possible future farming needs. Therefore, sufficient cultivatable land can be provided in time for agricultural production. [ABSTRACT FROM AUTHOR]

Accurate species delimitation is crucial for biodiversity conservation. The Acer series Campestria comprises four species, A. campestre L., A. miyabei Maxim., A. miaotaiense P. C. Tsoong, and A. yangjuechi Fang & P. L. Chiu. To clarify controversies over the taxonomic status of the latter three endangered species, we undertook phylogenomic, morphological, and niche differentiation analyses in series Campestria. Our coalescent species tree of 544 and 77 single‐copy nuclear genes supported series Campestria as monophyletic, with A. yangjuechi having the closest relationship with A. miaotaiense. However, in the plastome‐derived tree based on 64 protein coding sequences, the four species did not cluster together, and each of them grouped with some other sympatric Acer species. Given this nuclear‐cytoplasmic conflict, we hypothesize that A. yangjuechi have been subject to nuclear gene introgression and plastid (pt) capture involving another sympatric maple, that is, A. amplum Rehder. Principal component analysis and machine learning based on morphological data could not separate A. yangjuechi and A. miaotaiense, but they both could be clearly distinguished from A. miyabei. Moreover, the niche overlap tests of the two more widespread species, A. miyabei and A. miaotaiense, showed they clearly occupy distinct niches. Overall, we conclude that A. miyabei and A. miaotaiense are distinct species, while A. yangjuechi (endemic to Mt. Tianmu/East China) should be treated as a subspecies of A. miaotaiense. Our study points out that multiple lines of phylogenomic, morphological, and ecological evidence prove highly useful in species delimitation. Additionally, our results should help to inform conservation measures for endangered species of the genus Acer/series Campestria in East Asia. [ABSTRACT FROM AUTHOR]

The effects of invasive species on the local community (e.g., structure and stability) are highly environmentally dependent. Invasions of amphibious species usually take place in both xeric and humid environments, yet they are relatively poorly understood. In this study, we analyzed the communities that were dominated by Alternanthera philoxeroides using ecological niche and interspecific association. A total of 66 species and 67 species were recorded in the xeric environment and humid environment, respectively. In both environments, species in family Gramineae, such as Echinochloa crusgalli and Cynodon dactylon, exhibited a higher level of importance values and greater ecological niche widths. The interspecific association and stability of the dominant species were weak and the dominant species were relatively independent of each other. In the xeric environment, A. philoxeroides was more compatible with E. crusgalli and C. dactylon in terms of ecological niche requirements and habitat suitability. In humid habitats, A. philoxeroides had a greater correlation with E. crusgalli, C. dactylon, and Persicaria lapathifolia, suggesting a higher possibility of concomitant occurrence. Overall, we suggested that during the revegetation after A. philoxeroides invasion, E. crusgalli and C. dactylon can be the alternative plants. Meanwhile, alternative control measures for A. philoxeroides invasion in agricultural fields should give more consideration to the use of plants with economic or ecological value. [ABSTRACT FROM AUTHOR]

Potential vegetation distribution is an important study in environmental sciences. We utilized the Mixed Least Squares–Total Least Squares (MLS-TLS) method and the Signal Mode Decomposition method and the Ecological Niche model to identify the inter-correlations of internal climate change factors and constructed an environmental factor response regression model. We identified the resonance periods and trend relationships among climate factors (temperature, precipitation, and evapotranspiration) and found that the evapotranspiration of the watershed interferes with the correlation between temperature and precipitation on a five-year scale. The specific change degree of extreme climate indicators in the region was quantified by the Range of Variability Approach, among which the precipitation indicators were all below 33% (low change). There were significant differences between the key bioclimatic variables and Aspect of the development of suitable vegetation habitats. The difference between the Aspect and average daily air temperature is the main contributor to the spatial distribution of vegetation, and the mutual contribution is 76.19%. Our regression model can effectively simulate the potential distribution of vegetation (r = 0.854). Compared to the MaxEnt model, our regression model can quantitatively and intuitively provide suitable habitat values for Cryptomeria fortunei at any given location in the basin. Under future scenarios (2021–2040), suitable habitat for Cryptomeria fortunei in the eastern and western regions of the basin is projected to deteriorate further. The research results can provide some help for policymakers to eliminate the potential adverse effects of future climate change on regional ecology. [ABSTRACT FROM AUTHOR]

Simple Summary: The giant panda is an endemic species in China and the flagship species of global wildlife conservation. Habitat studies of the giant panda corridor can reveal their survival status, habitat environment, and the threats they face, which is crucial for giant panda population recovery and habitat conservation. The results of this study show that due to the opening of the National Road 5 (G5) Niba Mountain tunnel and the completion of the Niba Mountain giant panda corridor plan, the recovery of vegetation within the Niba Mountain giant panda corridor has led to the emergence of giant panda activity in the area, which may have spread to the central part of the reserve through the corridor. The habitat selection characteristics of the giant pandas in the corridor were clarified by investigating the microhabitats of the giant panda corridor in Niba Mountain. These findings can provide a reference for scientists to formulate practical habitat conservation and management measures for giant pandas in the study area. Habitat reduction and increased fragmentation are urgent issues for the survival and recovery of the giant panda (Ailuropoda melanoleuca). However, changes in the distribution and microhabitat selection of giant panda habitats in different seasons in the same region have rarely been assessed. To further understand giant panda habitat requirements, this study analyzed the giant panda habitat selection characteristics and differences using the sample data of the giant panda occurrence sites collected during 2020–2022. The results showed that the giant panda in both seasons selected medium altitudes (2000–2400 m), southeastern slopes, slopes less than 15°, taller tree layers (8–15 m) with a larger diameter at breast height (17–25 cm) and medium density (25–55%), shorter shrub layers (<4 m) with sparse density (<30%), and taller bamboo (>2 m) with high density (>35%). The giant panda microhabitat survey in the Niba Mountain corridor clarified the characteristics of suitable habitat selection for the giant panda in the corridor. The findings of the study can provide scientific references for the development of practical habitat conservation and management measures for giant pandas in the study area. [ABSTRACT FROM AUTHOR]

Global biodiversity decline and its cascading effects through trophic interactions pose a severe threat to human society. Establishing the impacts of biodiversity decline requires a more thorough understanding of multi‐trophic interactions and, more specifically, the effects that loss of diversity in primary producers has on multi‐trophic community assembly.Within a synthetic conceptual framework for multi‐trophic beta‐diversity, we tested a series of hypotheses on neutral and niche‐based bottom‐up processes in assembling herbivore and carnivore communities in a subtropical forest using linear models, hieratical variance partitioning based on linear mixed‐effects models (LMMs) and simulation.We found that the observed taxonomic, phylogenetic and functional beta‐diversity of both herbivorous caterpillars and carnivorous spiders were significantly and positively related to tree dissimilarity. Linear models and variance partitioning for LMMs jointly suggested that as a result of bottom‐up effects, producer dissimilarities were predominant in structuring consumer dissimilarity, the strength of which highly depended on the trophic dependencies on producers, the diversity facet examined, and data quality. Importantly, linear models for standardized beta‐diversities against producer dissimilarities implied a transition between niche‐based processes such as environmental filtering and competitive exclusion, which supports the role of bottom‐up effect in determining consumer community assembly.These findings enrich our mechanistic understanding of the 'Diversity Begets Diversity' hypothesis and the complexity of higher‐trophic community assembly, which is fundamental for sustainable biodiversity conservation and ecosystem management. [ABSTRACT FROM AUTHOR]

Dendrobium is a valuable traditional Chinese herb that contains active ingredients such as polysaccharides and alkaloids that have anti-aging, antioxidant, and immunomodulating effects. The appropriate distribution range of Dendrobium should be predicted from the perspective of ecological niche theory in order to preserve and utilize medicinal plant resources. In this study, Dendrobium nobile, Dendrobium officinale, and Dendrobium moniliforme were selected to predict the potential suitable distributions and ecological niche shifts. A comparison of 19 environmental variables of the three Dendrobium species revealed three climatic factors that differed significantly when the species were compared two at a time. The principal component analysis was carried out in order to screen seven climatic factors for ecological niche shift analysis. All three Dendrobium species were found to have a very similar ecological niche, but with a relatively small range of variability regarding certain climatic factors. Finally, the current and future suitable areas for these three Dendrobium species in China were predicted using the MaxEnt model and ArcGIS using the two representative concentration pathways (RCP 2.6 and 8.5). Overall, the analysis of the climatic factors' comparisons, niche shift, and current and future suitable areas of these three Dendrobium species provides a basis for medicinal plant resource conservation and utilization, and our methods could be applied to the study of other similar valuable medicinal plants. [ABSTRACT FROM AUTHOR]

The functional group (FG) system sensu Colin S. Reynolds of freshwater phytoplankton has been widely applied in many aspects of freshwater ecological assessments. However, there is no current consensus as to how and to why some functional coda shows multiple habitat templates in different water bodies. To test whether there are multiple habitat templates for some functional coda in the FG system, we used two mesotrophic deep reservoirs in China as examples, analysing phytoplankton taxonomic and environmental data collected in 4 seasons over two years. Results showed that a large proportion of the indicators had similar habitat templates within the FG system, whilst some species had multiple or different habitat templates according to their niche differentiation. The random forest (RF) model filtered a minimum set of environmental conditions and provided two potential habitat templates for Oocystis lacustris. One explanatory habitat template of clear water provided by the FG system was verified in the Nanwan Reservoir, and the other habitat template of high dissolved inorganic nitrogen (DIN) was found in the Nianyushan Reservoir. Further studies of the potential multiple habitat templates for some functional coda are recommended for its proper use. [ABSTRACT FROM AUTHOR]