Search Results (66)

Understanding the impacts of climate change on species’ geographic distributions is fundamental for biodiversity conservation and resource management. As a key plant group for ecological restoration and windbreak and sand fixation in arid and semi-arid ares in China’s Three Northern Regions (Northeast, North, and Northwest China), Caragana spp. exhibit distribution patterns whose regulatory mechanisms by environmental factors remain unclear, with a long-term lack of climatic explanations influencing their spatial distribution. This study integrated 2373 occurrence records of 44 Caragana species in China’s Three Northern Regions with four major environmental variable categories. Using the Biomod2 ensemble model, current and future climate scenario-based suitable habitats for Caragana spp. were predicted. This study innovatively combined quantitative analyses with Kira’s thermal indexes (warmth index, coldness index) and Wenduo Xu’s humidity index (HI) to elucidate species-specific relationships between distribution patterns and hydrothermal climatic constraints. The main results showed that (1) compared to other environmental factors, climate is the key factor affecting the distribution of Caragana spp. (2) The current distribution centroid of Caragana spp. is located in Alxa Left Banner, Inner Mongolia. In future scenarios, the majority of centroids will shift toward lower latitudes. (3) The suitable habitats for Caragana spp. will expand overall under future climate scenarios. High-stress scenarios exhibit greater spatial changes than low-stress scenarios. (4) Hydrothermal requirements varied significantly among species in China’s Three Northern Regions, and 44 Caragana species can be classified into five distinct types based on warmth index (WI) and humidity index (HI). The research findings will provide critical practical guidance for ecological initiatives such as the Three-North Shelterbelt Program and the restoration and management of degraded ecosystems in arid and semi-arid regions under global climate change. Full article

Climate change poses a major threat to forests, impacting the distribution and viability of key species. Quercus pyrenaica Willd., a marcescent oak endemic to the Iberian Peninsula (Portugal and Spain) and southwestern France and a structural species in submediterranean forests, is particularly susceptible to shifts in temperature and precipitation patterns. Aiming to assess its potential loss of suitable area under future climate scenarios, we developed high-resolution spatial distribution models to project the future habitat suitability of Q. pyrenaica under two climate change scenarios (SSP3-7.0 and SSP5-8.5) for the periods 2070 and 2100. Our model, which has an excellent predictive performance (AUC of 0.971 and a TSS of 0.834), indicates a predominantly northward shift in the potential distribution of the species, accompanied by substantial habitat loss in southern and lowland regions. Long-term potential suitable area may shrink to 42% of that currently available. This, combined with the limited natural dispersal capacity of the species, highlights the urgency of targeted management and conservation strategies. These results offer critical insights to inform conservation strategies and forest management under ongoing climate change. Full article

Dutch elm disease is one of the most devastating plant diseases, primarily spread through bark beetles. Scolytus scolytus is a key vector of this disease. In this study, distribution data of S. scolytus were collected and filtered. Combined with environmental and climatic variables, an ensemble model was developed using the Biomod2 platform to predict its potential geographical distribution in China. The selection of climate variables was critical for accurate prediction. Eight bioclimatic factors with high importance were selected from 19 candidate variables. Among these, the three most important factors are the minimum temperature of the coldest month (bio6), precipitation seasonality (bio15), and precipitation in the driest quarter (bio17). Under current climate conditions, suitable habitats for S. scolytus are mainly located in the temperate regions between 30° and 60° N latitude. These include parts of Europe, East Asia, eastern and northwestern North America, and southern and northeastern South America. In China, the low-suitability area was estimated at 37,883.39 km², and the medium-suitability area at 251.14 km². No high-suitability regions were identified. However, low-suitability zones were widespread across multiple provinces. Under future climate scenarios, low-suitability areas are still projected across China. Medium-suitability areas are expected to increase under SSP370 and SSP585, particularly along the eastern coastal regions, peaking between 2041 and 2060. High-suitability zones may also emerge under these two scenarios, again concentrated in coastal areas. These findings provide a theoretical basis for entry quarantine measures and early warning systems aimed at controlling the spread of S. scolytus in China. Full article

Ostryopsis davidiana shrubs, widely distributed in northern China, have been significantly affected by global warming. Based on the current geographical distribution data of O. davidiana in China, this study used climate data, soil data, topographic data, human activity data, and the “biomod2” integrated model to conduct an integrated study on the suitable habitat of O. davidiana under the current scenario and three future climate scenarios (SSP126, SSP370, and SSP585). The results showed the following: (1) The suitable habitats of O. davidiana are mainly concentrated in the northwest and north China regions, accounting for about 9.09% of the national area, centered in Shanyin County, Shuozhou City, Shanxi Province. (2) The suitable habitats of O. davidiana are mainly influenced by temperature and precipitation, with precipitation of wettest quarter (Bio16), isothermality (Bio3), and maximum temperature of warmest month (Bio5) being the key driving factors, with contribution rates of 25.69%, 24.31%, and 14.45%, respectively. (3) Under the three future climate scenarios, the suitable habitats of O. davidiana are expected to contract significantly, with only the low suitability areas expanding, while the rest would be contracting, showing a trend of losing most of their original habitat. The centroid of the suitable habitat would be shifting westward, and the suitable habitats would be generally migrating to higher elevation areas. (4) Climate change reduces the aggregation of O. davidiana, leading to gradual habitat fragmentation. This study provides a theoretical basis for the conservation of O. davidiana. Full article

The Chinese forest frog (Rana chensinensis) has high ecological and economic value and is an ecologically important species that is very sensitive to environmental changes. However, climate change and increasing human activity are posing growing threats to its natural habitat. To address these challenges, this study aimed to predict the current and future geographic distribution of the Chinese forest frog and to identify the environmental drivers influencing its habitat suitability. Here, the optimized MaxEnt and Biomod2 were used to assess 127 species occurrence records and 22 environmental variables and model and analyze changes in the geographic distribution of the Chinese forest frog in different periods. The environmental factors underlying geographical distribution changes and migration trends in distribution areas under climate change were assessed. The optimized MaxEnt model generated the best predictions, showing that the current most highly suitable areas are located in Chongqing, Sichuan, and Gansu provinces. The optimized MaxEnt model demonstrated exceptionally high predictive accuracy, with mean AUC values of 0.968 ± 0.000 and TSS values of 0.800 ± 0.089. The total area of the current potentially suitable habitat was estimated at 426 × 10⁴ km². The principal ecological factors influencing the distribution of the Chinese forest frog are Bio9, Bio10, and human activity. Under future scenarios, the potentially suitable habitat for the Chinese forest frog is projected to shift westward and southward. Compared to the current situation, the potentially suitable habitat for the Chinese forest frog is expected to significantly shrink across all four future scenarios (2050s-SSP126, 2050s-SSP585, 2090s-SSP126, and 2090s-SSP585), posing serious threats to its survival. This study not only identifies the key ecological factors limiting the potential distribution of the Chinese forest frog but also provides a scientific basis and data support for the development of conservation strategies and habitat restoration efforts. Full article

Argentina anserina (Rosaceae), a perennial herb, forms enlarged tuberous roots (commonly referred to as “ginseng fruit”) exclusively in the Qinghai–Tibet Plateau, making it a unique medicinal and edible plant resource in this region. The upper reaches of the Dadu River and Minjiang River are one of its primary production areas in China. This study employs an ensemble model to simulate the potential distribution of A. anserina in this region, predicting the impacts of future climate change on its distribution, ecological niche, and centroid migration patterns. Additionally, a cultivation productivity evaluation model integrating ecological suitability and nutritional components was developed to delineate potential cultivation areas. Results indicate that high-suitability habitats span 0.37 × 10⁴ km² (7.39% of the total suitable area), exhibiting a patchy and fragmented distribution in Aba County, Rangtang County, Jiuzhi County, and Banma County. Core cultivation areas cover 3.78 × 10⁴ km², distributed across Aba County, Rangtang County, Jiuzhi County, Seda County, Banma County, Hongyuan County, and Markam City. Under future climate scenarios, the suitable distribution area of A. anserina will gradually decline with rising temperatures, migrating to higher-latitude northern regions, accompanied by increased niche migration. By the 2090s under the SSP5-8.5 scenario, the centroid demonstrates the largest migration amplitude, with high-suitability habitats showing a “collapsing” polarization pattern and near-complete niche separation from the previous period, indicating significant changes. Collectively, these results provide a theoretical basis for the sustainable utilization of A. anserina in the upper Dadu River and Minjiang River basin. Full article

Planococcus minor is an invasive pest of significant economic importance that has attracted international attention. Predicting the potential geographic distribution of P. minor under climate change is crucial to developing effective prevention and control strategies for safeguarding agricultural productivity. In this study, we selected four species distribution models (GBM, GLM, MARS, MAXENT) and utilized the Biomod2 package to construct an ensemble model for predicting the suitable habitats of P. minor under the averaged climate conditions of 1970–2000 and 2041–2060 (2050s), including a low-emission pathway (SSP1-2.6) and a high-emission pathway (SSP5-8.5). Among the 19 bioclimatic variables considered, precipitation of the wettest quarter and temperature seasonality were identified as the most influential factors affecting the distribution of P. minor. Under the averaged climate conditions of 1970–2000, suitable habitats for P. minor are mainly distributed in tropical and subtropical regions worldwide. In China, highly suitable zones are concentrated in Yunnan, Guangxi, Guangdong, Hainan, and Taiwan. In the future, the global range of P. minor is projected to expand, with some highly suitable areas transitioning toward medium and low suitability. Under the high-emission pathway (SSP5-8.5) scenario, suitable habitats in China are anticipated to exhibit a pronounced trend of inland expansion. Establishing an ensemble model to predict the potential geographic distribution of P. minor will facilitate the assessment of invasion and spread risks, thereby providing a scientific foundation for developing targeted prevention and monitoring strategies for relevant regions. Full article

Climate change significantly impacts species distribution and survival, particularly for habitat specialists with limited dispersal abilities. This study investigates the current and future distribution of Tylonycteris pachypus, one of the world’s smallest bats specialized in bamboo-dwelling, using ensemble modeling approaches. Based on comprehensive occurrence data and seven environmental variables, we developed an ensemble model using the Biomod2 platform, achieving high predictive accuracy (AUC: 0.981, TSS: 0.877). Three environmental variables were identified as crucial determinants: minimum temperature of the coldest month (40.90% contribution), maximum temperature of the warmest month (38.38%), and precipitation of the wettest quarter (11.09%). Currently, highly suitable habitats (291.893 × 10⁴ km²) are concentrated in three main regions: southern China and Indochina Peninsula, Myanmar–Bangladesh–northeastern India, and isolated areas in southwest India and Thailand. Under future climate scenarios, particularly SSP585, suitable habitats are projected to decrease substantially (64.4% reduction by 2090s), with a notable northward shift in distribution. However, the species’ limited dispersal ability, specific habitat requirements, and geographical barriers may constrain its capacity to track these climate-driven changes. Our findings highlight the vulnerability of T. pachypus to climate change and emphasize the need for targeted conservation strategies, including protecting climate-resilient habitats and maintaining bamboo forest corridors. This study provides a comprehensive framework for monitoring and conserving this specialized species under climate change, while considering its unique ecological constraints and dispersal limitations. Full article

The Yancheng coastal wetlands serve as a crucial stopover site along the East Asian–Australasian Flyway. The rapid expansion of aquaculture has led to a significant decline in natural wetlands, impacting both the distribution and quality of waterbird habitats. Following the designation of the region as a World Natural Heritage site in 2019, the local government has prioritized the protection of waterbird habitats, leading to the large-scale withdrawal of aquaculture from the region. Nevertheless, the impact of the fishing withdrawal on waterbird habitat selection and the ecological benefits it brought remain unknown. In this study, based on the identification of fishing withdrawal zones in the Yancheng coastal area, six waterbird groups, Anatidae, Ardeidae, Charadriiformes, Laridae, Gruidae and Ciconiidae, were selected to construct an evaluation index system for habitat suitability. The Biomod2 ensemble model was employed to analyze the spatial differences of suitable habitats for waterbirds within the fishing withdrawal zones. The result revealed the following: (1) As of 2022, the area of fishing withdrawal zones had reached 2.23 × 10⁴ ha, primarily distributed in Beihuan and Nanhuan. Among these, the area of fishing withdrawal zones in Nanhuan was the largest, reaching 6.78 × 10³ ha. (2) Unsuitable area for waterbirds was largest in the fishing withdrawal zones, with a proportion of 60% and 58% for Gruidae and Ciconiidae, respectively. (3) The rich nutrients, high coverage and tall stature of emergent vegetation in the fishing withdrawal zones led to a reduction in water surface area, resulting in significant adverse effects on the suitable habitats for Charadriiformes and Gruidae. Therefore, the results suggest that most areas after fishing withdrawal were still not suitable habitats for waterbirds. The implementation of scientific fishing withdrawal practices, along with ecological restoration and management, is crucial for improving the habitat suitability in fishing withdrawal zones. This study provides valuable insights for more purposeful selection of fishing withdrawal sites, and more scientific management and restoration of these areas to enhance their ecological benefits. Full article

Rapid climate change has significantly impacted species distribution patterns, necessitating a comprehensive understanding of dominant tree dynamics for effective forest resource management and utilization. The Camellia subgenus Camellia, a widely distributed taxon in subtropical China, represents an ecologically and economically important group of woody plants valued for both oil production and ornamental purposes. In this study, we employed the BIOMOD2 ensemble modeling framework to investigate the spatial distribution patterns and range dynamics of the subgenus Camellia under projected climate change scenarios. Our analysis incorporated 1455 georeferenced occurrence records from 15 species, following the filtering of duplicate points, along with seven bioclimatic variables selected after highly correlated factors were eliminated. The ensemble model, which integrates six single species distribution models, demonstrated robust predictive performance, with mean true skil l statistic (TSS) and area under curve (AUC) values exceeding 0.8. Our results identified precipitation of the coldest quarter (Bio19) and temperature seasonality (Bio4) as the primary determinants influencing species distribution patterns. The center of species richness for the subgenus Camellia was located in the Nanling Mountains and eastern Guangxi Zhuang Autonomous Region. The projections indicate an overall expansion of suitable habitats for the subgenus under future climate conditions, with notable scenario-dependent variations: distribution hotspots are predicted to increase by 8.86% under the SSP126 scenario but experience a 2.53% reduction under the SSP585 scenario. Furthermore, a westward shift in the distribution centroid is anticipated. To ensure long-term conservation of Camellia genetic resources, we recommend establishing a germplasm conservation center in the Nanling Mountains region, which represents a critical biodiversity hotspot for this taxon. Full article

This study employs the Biomod2 model, along with 22 bioclimatic variables, to predict the geographic distribution of the medicinal plant Epimedium acuminatum Franch. for the current period and three future timeframes (2050s, 2070s, and 2090s). Ultimately, 11 key environmental variables were identified as critical for assessing the habitat suitability of the medicinal plant. These include the annual mean temperature (Bio 1), isothermally (Bio 3), temperature seasonality (Bio 4), maximum temperature of the warmest month (Bio 5), minimum temperature of the coldest month (Bio 6), mean temperature of the driest quarter (Bio 9), mean temperature of the coldest quarter (Bio 11), precipitation of the driest quarter (Bio 17), elevation (Elev), aspect, and slope. The results indicate that the current high suitability areas are primarily distributed across Yunnan, Chongqing, Sichuan, Hunan, Guangxi, and Hubei provinces. In the future, the extent of high suitability areas is expected to increase. This study aims to provide a theoretical reference for the conservation of E. acuminatum genetic resources from a geographic distribution perspective. Full article

Si₃N₄ ceramics and composites stand out for their exceptional mechanical and thermal properties. Compared with conventional ceramic forming processes, 3D printing via vat photopolymerization not only ensures high geometric precision but also improves the forming efficiency and strength of green body. Nevertheless, the grayish appearance of Si₃N₄ and its relatively high refractive index can adversely affect the photocuring behavior in ceramic slurries. The primary objectives focus on enhancing the curing performance and rheological properties of slurries, minimizing defects during post-processing, and improving the relative density and mechanical properties of Si₃N₄ ceramics. Key advancements include slurry optimization via refractive index matching, biomodal particle gradation and surface modification, while the integration of whisker/fiber additions or polymer-derived ceramic strategies enhances mechanical properties. In addition, controlling the atmosphere and heating rate of the post-processing innovations can achieve a relative density of more than 95%. This paper introduces the mechanisms of vat photopolymerization and then summarizes the strategies for improving Si₃N₄ ceramic slurries as well as controlling the printing and debinding/sintering processes. It further highlights the ways in which different approaches can be used to enhance the properties of Si₃N₄ slurries and ceramic parts. Finally, applications of Si₃N₄ ceramics and composites via vat photopolymerization in various fields such as aviation, aerospace, energy, electronics, chemical processes, and biomedical implants are also presented to point out future opportunities and challenges. Full article

Climate and land use directly influence species’ spatial distribution, which can alter species’ distribution and lead to significant changes in biodiversity spatial patterns. There are few reports on how climate and land use changes affect plant biodiversity spatial distribution patterns. This study focuses on Chinese endemic tree plants, analyzing the changes in hotspots under current and future conditions (2050 SSP1–2.6 and SSP5–8.5 climate and land use scenarios). Using spatial distribution data of endemic tree plants in China, the Biomod2-integrated species distribution model, and the “top 5% diversity” hotspot identification method, we examine species richness (SR), functional diversity (FD), and phylogenetic diversity (PD). The results indicate that with changes in climate and land use: (1) significant shifts occur in the spatial distribution patterns of hotspots. Although the number of hotspots identified by different diversity indices varies, fragmentation increases across all scenarios. (2) Hotspots tend to concentrate in low-latitude and high-altitude regions. In future scenarios, the longitudinal position of hotspots is significantly lower, and their elevation is significantly higher compared to the current scenario. (3) The spatial patterns of plant diversity in hotspots also change significantly. The SR and PD patterns show similar distribution trends across different scenarios. Under current conditions, the highest values of SR and PD are found in the eastern mountainous regions, such as the Wuyi Mountains and Nanling Mountains, while in future scenarios, they shift to central and western mountainous areas like the Qinling Mountains and Hengduan Mountains. The FD distribution pattern differs, with its highest values consistently found in southeastern Tibet and the Hengduan Mountains across all scenarios. Thus, climate and land use changes not only alter the spatial distribution of hotspots but also change plant diversity within them. This study provides scientific evidence for regional-scale biodiversity conservation under global change. Full article

Hippophae neurocarpa is a relatively new member of the Rhamnus genus that has various potential edible and medicinal values, but still needs to be further developed. To better develop H. neurocarpa, it is crucial to determine its current and future population distribution. This study utilized the “Biomod2” package in R to integrate five individual models and investigate the effects of climate change on the potential distribution of H. neurocarpa, as well as the key climatic factors influencing its distribution. The results indicated that, under the current scenario, the potential distribution of H. neurocarpa is mainly concentrated in the eastern parts of the Loess Plateau and the Qinghai–Tibet Plateau. In the future, its potential suitable habitats will undergo varying degrees of change: the area of medium/low suitability will decrease, while the area of high suitability will shift westward and increase. In the analysis of area changes, it was found that some potential suitable habitats in Sichuan and Shaanxi will directly transition from highly suitable to unsuitable areas. Key environmental variable analysis showed that temperature, particularly low temperature, is a crucial factor affecting the distribution of H. neurocarpa. Additionally, altitude also has a significant impact on its distribution. This study predicted the potential suitable habitats of H. neurocarpa, which will aid in its future development and provide reference for selecting regions suitable for its cultivation. Full article

Climate change has presented considerable challenges in the management of urban forests and trees. Varieties of studies have predicted the potential changes in species distribution by employing single-algorithm species distribution models (SDMs) to investigate the impacts of climate change on plant species. However, there is still limited quantitative research on the impacts of climate change on the suitable distribution ranges of commonly used urban tree species. Therefore, our study aims to optimize traditional SDMs by integrating multiple machine learning algorithms and to propose a framework for identifying suitable distribution ranges of urban trees under climate change. We took Michelia chapensis, a tree species of particular significance in southern China, as a pilot tree species to investigate the evolution of its suitable distribution range in the context of two future climate scenarios (SSP126 and SSP585) across four periods (2030s, 2050s, 2070s, and 2090s). The findings indicated that the ensemble SDM showed strong predictive capacity, with an area under the curve (AUC) value of 0.95. The suitable area for Michelia chapensis is estimated at 15.9 × 10⁵ km² currently and it will expand in most areas under future climate scenarios according to the projection. However, it will contract in southeastern Yunnan, central Guangdong, the Sichuan Basin, northern Hubei, and Jiangxi, etc. The central location of the current suitable distribution area is located in Hengyang, Hunan (27.36° N, 112.34° E), and is projected to shift westward with climate change in the future. The migration magnitude is positively correlated with the intensity of climate change. These findings provide a scientific basis for the future landscape planning and management of Michelia chapensis. Furthermore, the proposed framework can be seen as a valuable tool for predicting the suitable distribution ranges of urban trees in response to climate change, providing insights for proactive adaptation to climate change in urban planning and landscape management. Full article