Distribution Of Suitable Areas Research Articles

Predicting the Impact of Climate Change on the Distribution of a Neglected Arboviruses Vector (Armigeres subalbatus) in China

The geographic boundaries of arboviruses continue to expand, posing a major health threat to millions of people around the world. This expansion is related to the availability of effective vectors and suitable habitats. Armigeres subalbatus (Coquillett, 1898), a common and neglected species, is of increasing interest given its potential vector capacity for Zika virus. However, potential distribution patterns and the underlying driving factors of Ar. subalbatus remain unknown. In the current study, detailed maps of their potential distributions were developed under both the current as well as future climate change scenarios (SSP126 and SSP585) based on CMIP6 data, employing the MaxEnt model. The results showed that the distribution of the Ar. subalbatus was mainly affected by temperature. Mean diurnal range was the strongest predictor in shaping the distribution of Ar. subalbatus, with an 85.2% contribution rate. By the 2050s and 2070s, Ar. subalbatus will have a broader potential distribution across China. There are two suitable expansion types under climate change in the 2050s and 2070s. The first type is continuous distribution expansion, and the second type is sporadic distribution expansion. Our comprehensive analysis of Ar. subalbatus’s suitable distribution areas shifts under climate change and provides useful and insightful information for developing management strategies for future arboviruses.

Effects of Climate Change and Environmental Factors on Bamboo (Ferrocalamus strictus), a PSESP Unique to China

Bamboo is a plant that may replace plastics and wood as a new green environmental protection material that can be developed. Ferrocalamus strictus is a very special and rare bamboo which is a plant species with extremely small populations (PSESP) endemic to Yunnan, China, and it is listed as a China key national first-class protected wild plant. To explore the effects of extreme climate and environmental changes on this PSESP, we conducted a case study on the response of F. strictus to climate under two extreme future emission scenarios. We combined 29 environmental variables, including the temperature, precipitation, altitude, slope, aspect, soil pH, soil organic carbon content, and mean UV-B radiation of the highest month, to analyze the important environmental factors limiting the distribution of F. strictus and identified the priority conservation areas (PCAs) of F. strictus. Under the two future extreme climate scenarios, the core potential suitable distribution area of F. strictus would decrease by 26%–34% in 2040, 44%–46% in 2060, and 23%–58% in 2080, respectively. Bio18 (precipitation in the warmest quarter) and Bio3 (isotherm) were the two key factors limiting the geographical distribution of F. strictus (the contribution rates were 40.1% and 18.45%, respectively). The results of this study show that F. strictus is in urgent need of protection and PSESPs require more attention.

Analysis of potential distribution of Spodoptera frugiperda in western China

• Over 60% of the areas in western China are suitable distribution areas of Spodoptera frugiperda . • More than 20% of the areas in western China are high suitable distribution area for Spodoptera frugiperda. • Greenhouses may raise the risk of Spodoptera frugiperda infestations in western China. Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), a newly invaded pest that breaks out fast and severely, causes a serious threat to the national security of food production in China. In this study, the MaxEnt model was used to predict the potentially suitable distribution area of S. frugiperda in western China. The potential distribution of S. frugiperda was predicted using meteorological factors from the correlation analysis. According to the result, a satisfactory AUC value in the MaxEnt model indicates that the prediction model has good accuracy, which is sufficient for predicting the suitable distribution areas of S. frugiperda in western China. The prediction results show that the potential distribution risk of S. frugiperda is high in western Gansu, eastern Qinghai, Shaanxi, most regions of Ningxia, and part regions of Tibetan, and the most suitable areas for S. frugiperda in Xinjiang are Hami, Ili, Urumqi, Hotan and Aksu, and more than 60% of western China are suitable distribution areas for S. frugiperda . Western China is one of the main wheat and corn producing areas in China. Clarifying the potential geographical distribution of S. frugiperda in western China is essential for early warning as well as prevention and control.

Impacts of climate change on species distribution patterns of Polyspora sweet in China.

Climate change is an important driver of species distribution and biodiversity. Understanding the response of plants to climate change is helpful to understand species differentiation and formulate conservation strategies. The genus Polyspora (Theaceae) has an ancient origin and is widely distributed in subtropical evergreen broad-leaved forests. Studies on the impacts of climate change on species geographical distribution of Chinese Polyspora can provide an important reference for exploring the responses of plant groups in subtropical evergreen broad-leaved forests with geological events and climate change in China. Based on the environmental variables, distribution records, and chloroplast genomes, we modeled the potential distribution of Chinese Polyspora in the Last Glacial Maximum, middle Holocene, current, and future by using MaxEnt-ArcGIS model and molecular phylogenetic method. The changes in the species distribution area, centroid shift, and ecological niche in each periods were analyzed to speculate the response modes of Chinese Polyspora to climate change in different periods. The most important environmental factor affecting the distribution of Polyspora was the precipitation of the driest month, ranging from 13 to 25 mm for the highly suitable habitats. At present, highly suitable distribution areas of Polyspora were mainly located in the south of 25°N, and had species-specificity. The main glacial refugia of the Chinese Polyspora might be located in the Ailao, Gaoligong, and Dawei Mountains of Yunnan Province. Jinping County, Pingbian County, and the Maguan County at the border of China and Vietnam might be the species differentiation center of the Chinese Polyspora. Moderate climate warming in the future would be beneficial to the survival of P.axillaris, P.chrysandra, and P.speciosa. However, climate warming under different shared socio-economic pathways would reduce the suitable habitats of P.hainanensis and P.longicarpa.

Evaluation of climate factors affecting the quality of red huajiao (Zanthoxylum bungeanum maxim.) based on UPLC-MS/MS and MaxEnt model.

Through field investigation, UPLC-MS/MS technology and MaxEnt model were performed to predict the suitable distribution area for red huajiao (Zanthoxylum bungeanum maxim.) in China from 2021s to 2060s, and evaluate the effects of climate factors on the quality of red huajiao. The results demonstrated that mean temperature of the coldest quarter and min temperature of the coldest month were the most important environmental variables influencing red huajiao distribution. Suitable habitats for red huajiao were located mainly in dry and hot valley zone in the Qinba Mountains and the semi-humid and semi-arid areas of the Loess Plateau. The amides contents were higher in high suitability areas, while it was decreased in medium and low suitability areas, and temperature, wind speed and precipitation played a key role in their accumulation. This investigation was of great significance for the planting area optimization, quality control, benefit improvement and industrial development of red huajiao.

Evolutionary history of genus Coptis and its dynamic changes in the potential suitable distribution area.

The genus Coptis belongs to the Ranunculaceae family, containing 15 recognized species highly diverse in morphology. It is a conspicuous taxon with special evolutionary position, distribution pattern and medicinal value, which makes it to be of great research and conservation significance. In order to better understand the evolutionary dynamics of Coptis and promote more practical conservation measures, we performed plastome sequencing and used the sequencing data in combination with worldwide occurrence data of Coptis to estimate genetic diversity and divergence times, rebuild biogeographic history and predict its potential suitable distribution area. The average nucleotide diversity of Coptis was 0.0067 and the hotspot regions with the highest hypermutation levels were located in the ycf1 gene. Coptis is most likely to have originated in North America and Japanese archipelago and has a typical Eastern Asian and North American disjunct distribution pattern, while the species diversity center is located in Mid-West China and Japan. The crown age of the genus is estimated at around 8.49 Mya. The most suitable climatic conditions for Coptis were as follows: precipitation of driest quarter > 25.5mm, annual precipitation > 844.9mm and annual mean temperature -3.1 to 19 °C. The global and China suitable area shows an upward trend in the future when emission of greenhouse gases is well controlled, but the area, especially in China, decreases significantly without greenhouse gas policy interventions. The results of this study provide a comprehensive insight into the Coptis evolutionary dynamics and will facilitate future conservation efforts.

Assessing habitat suitability and selecting optimal habitats for relict tree Cathaya argyrophylla in Hunan, China: Integrating pollen size, environmental factors, and niche modeling for conservation

The endangered plant Cathaya argyrophylla Chun et Kuang is the only species in the genus and is endemic to China, and because of challenged regeneration and shrinking habitats, the protected areas (PAs) need to be expanded in Hunan Province. In this study, a maximum entropy model (MaxEnt) was used to predict the potentially suitable habitats and population centroid migrations for C. argyrophylla in Hunan under four climate change scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) at four time points (2030, 2050, 2070, and 2090) based on thirteen environmental variables. For the first time, optimal habitats that could support breeding Cathaya populations with good fruiting quality in Hunan were identified considering relations between pollen grain size and environmental variables. Of the total area, 10.69 % (22.63 × 103 km2) was suitable for C. argyrophylla, which was distributed primarily in western and southern parts of Hunan. Monthly precipitation in August was the environmental variable that contributed the most (28.2 %) to C. argyrophylla distribution. Other influential variables were annual mean temperature, annual precipitation, mean temperature of the wettest quarter, monthly solar radiation in May, and precipitation of the driest month. The suitable distribution area for C. argyrophylla decreased overall under the climate change scenarios, with SSP2-4.5 the exception. Population centroid of C. argyrophylla shifted overall slightly toward southeast areas with more abundant precipitation in Hunan under climate change. The average shift distance was 3.89 km, and the longest migration distance (8.84 km) was in 2090 under SSP1-2.6. In Hunan, 642.12 km2 were authority identified as optimal habitat based on the current climate. It is proposed that areas with altitudes between 758 m and 1,500 m be treated as crucial PAs networks for C. argyrophylla, mainly including Nanyue, Yanling, Guidong, Xinning, and Zixing counties and districts. The goal of the study was to assist in the conservation and management of C. argyrophylla, but it also provides an example of how to evaluate optimal habitats for those endangered species that need to produce populations with specific superior characteristics.

Prediction of the Current and Future Distributions of the Hessian Fly, Mayetiola destructor (Say), under Climatic Change in China.

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), is a destructive wheat pest worldwide and an important alien species in China. Based on 258 distribution records and nine environmental factors of the Hessian fly, we predicted the potential distribution area in China under three current and future (2050s and 2070s) climate change scenarios (RCP2.6, RCP4.5, and RCP8.5) via the optimized MaxEnt model. Under the current climate conditions, the suitable distribution areas of the Hessian fly in China were 25-48° N, 81-123° E, and the total highly suitable distribution area is approximately 9.63 × 105 km2, accounting for 9.99% of the total national area. The highly suitable areas are mainly located in northern Xinjiang and central and eastern China. With the rising global temperatures, except for the high-suitable areas under the RCP8.5 scenario, most potential geographic distribution areas would expand in the future. The minimum temperature in February (tmin-2), precipitation in March (prec-3), maximum temperature in November (tmax-11), and precipitation seasonality (bio-15) are important factors that affect the potential geographic distribution of the Hessian fly. This study provides an important reference and empirical basis for management of the Hessian fly in the future.

Simulation the potential distribution of Dendrolimus houi and its hosts, Pinus yunnanensis and Cryptomeria fortunei, under climate change in China.

Due to climate change, it is significant to explore the impact of rising temperatures on the distribution of Dendrolimus houi Lajonquiere (Lepidoptera) and its host plants, Pinus yunnanensis and Cryptomeria fortunei, and to simulate their suitable future distribution areas in order to provide a theoretical basis for the monitoring of, and early warning about, D. houi and the formulation of effective prevention and control policies. Based on the known distribution areas of, and relevant climate data for, D. houi, P. yunnanensis, and C. fortunei, their suitable habitat in China was predicted using the ENMeval data package in order to adjust the maximum entropy (MaxEnt) model parameters. The results showed that the regularization multiplier was 0.5 when the feature combination was LQHPT, with a MaxEnt model of lowest complexity and excellent prediction accuracy. The main climate variable affecting the geographical distribution of D. houi, P. yunnanensis, and C. fortunei is temperature, specifically including isothermality, temperature seasonality, maximum temperature of warmest month, minimum temperature of warmest month, average temperature of coldest quarter. The potential suitable distribution areas for P. yunnanensis and D. houi were similar under climate change, mainly distributed in southwest China, while C. fortunei was mainly distributed in southeast China. Under different future-climate scenarios, the areas suitable for the three species will increase, except for P. yunnanensis in the 2070s under Shared Socioeconomic Pathway 5-8.5. With climate change, all three species were found to have a tendency to migrate to higher latitudes and higher altitudes. The centroids of the areas suitable for P. yunnanensis and D. houi will migrate to the northwest and the centroids of the areas suitable for C. fortunei will migrate to the northeast.

Distributional Response of the Rare and Endangered Tree Species Abies chensiensis to Climate Change in East Asia.

Globally, increasing temperatures due to climate change have severely affected natural ecosystems in several regions of the world; however, the impact on the alpine plant may be particularly profound, further raising the risk of extinction for rare and endangered alpine plants. To identify how alpine species have responded to past climate change and to predict the potential geographic distribution of species under future climate change, we investigated the distribution records of A. chensiensis, an endangered alpine plant in the Qinling Mountains listed in the Red List. In this study, the optimized MaxEnt model was used to analyse the key environmental variables related to the distribution of A. chensiensis based on 93 wild distribution records and six environmental variables. The potential distribution areas of A. chensiensis in the last interglacial (LIG), the last glacial maximum (LGM), the current period, and the 2050s and 2070s were simulated. Our results showed that temperature is critical to the distribution of A. chensiensis, with the mean temperature of the coldest quarter being the most important climatic factor affecting the distribution of this species. In addition, ecological niche modeling analysis showed that the A. chensiensis distribution area in the last interglacial experiencing population expansion and, during the last glacial maximum occurring, a population contraction. Under the emission scenarios in the 2050s and 2070s, the suitable distribution area would contract significantly, and the migration routes of the centroids tended to migrate toward the southern high-altitude mountains, suggesting a strong response from the A. chensiensis distribution to climate change. Collectively, the results of this study provide a comprehensive and multidimensional perspective on the geographic distribution pattern and history of population dynamics for the endemic, rare, and endangered species, A. chensiensis, and it underscores the significant impact of geological and climatic changes on the geographic pattern of alpine species populations.

Niche divergence at the intraspecific level in an endemic rare peony (Paeonia rockii): A phylogenetic, climatic and environmental survey.

Ecological factors have received increasing attention as drivers of speciation but also in the maintenance of postspeciation divergence. However, the relative significance of the responses of species to climate oscillations for driving niche divergence or conservatism in the evolution of many species that pass through diverse environments and limited geographical boundaries remains poorly understood. Paeonia rockii (one of the ancient species of Paeonia) comprising two subspecies called Paeonia rockii subsp. rockii and Paeonia rockii subsp. taibaishanica is an endemic, rare, and endangered medicinal plant in China. In this study, we integrated whole chloroplast genomes, and ecological factors to obtain insights into ecological speciation and species divergence in this endemic rare peony. RAxML analysis indicated that the topological trees recovered from three different data sets were identical, where P. rockii subsp. rockii and P. rockii subsp. taibaishanica clustered together, and molecular dating analyses suggested that the two subspecies diverged 0.83 million years ago. In addition, ecological niche modeling showed that the predicted suitable distribution areas for P. rockii subsp. rockii and P. rockii subsp. taibaishanica differed considerably, although the predicted core distribution areas were similar, where the population contracted in the last interglacial and expanded in the last glacial maximum. Under the emissions scenarios for the 2050s and 2070s, the suitable distribution areas were predicted to contract significantly, where the migration routes of the two subspecies tended to migrate toward high latitudes and elevations, thereby suggesting strong responses of the distributions of the two subspecies to climate change. These findings combined with the phylogeographic relationships provide comprehensive insights into niche variation and differentiation in this endemic rare peony, and they highlight the importance of geological and climatic changes for species divergence and changes in the population geographic patterns of rare and endangered medicinal plants in East Asia.

Understanding the Effects of Climate Change on the Distributional Range of Plateau Fish: A Case Study of Species Endemic to the Hexi River System in the Qinghai–Tibetan Plateau

Prediction of species’ potentially suitable distribution areas and their range shifts under future climate change has long been the focus of macroecology and biogeography. Gymnocypris chilianensis of Schizothoracinae and Triplophysa hsutschouensis of Triplophysa are isolated to the Shiyang, Heihe, and Shule Rivers of the Hexi River system, listed from east to west, along the northeastern part of the Qinghai–Tibetan Plateau (QTP). This spatial distribution provides a valuable set of conditions for investigating patterns of habitat suitability and potential impacts of accelerated plateau climate change on endemic plateau fish species. Here, we employed the maximum entropy (MaxEnt) model to first evaluate potentially suitable habitats of the two species and identify the primary impact factors under the current climate based on occurrence records and environmental variables; then, we predicted changes in suitable habitat areas and distribution centers under two representative concentration pathways (RCPs), 2.6 and 8.5, for the future (2050 and 2070). The results showed that annual precipitation and altitude were the two most important environmental factors predicting the suitable habitat of G. chilianensis and T. hsutschouensis. The areas of suitable habitat for G. chilianensis and T. hsutschouensis experienced a sequential westward decrease from the Shiyang River towards the Heihe and Shule Rivers under the current climate conditions. Under future climate changes, the areas of the potential geographical distribution of G. chilianensis and T. hsutschouensis were concentrated eastward towards the Shiyang River, the area of the species’ ancestral origins. Suitable habitat centers of the two species shifted eastward from the Heihe River to the Shiyang River and higher altitude areas. Additionally, G. chilianensis showed a greater reduction in suitable habitat and greater eastward range shift compared to T. hsutschouensis. These findings provide empirical evidence that accelerated climate change on the QTP has severe consequences for endemic populations with restricted and isolated habitats. This study demonstrates that different plateau fish have similarities and differences in their responses to climate change. Our findings also highlight that the effects of climate change must be incorporated into the integrated conservation plans for fish species on the QTP and its adjacent areas.

Predicting the distribution of plant associations under climate change: A case study on Larix gmelinii in China.

Association is the basic unit of plant community classification. Exploring the distribution of plant associations can help improve our understanding of biodiversity conservation. Different associations depend on different habitats and studying the association level is important for ecological restoration, regional ecological protection, regulating the ecological balance, and maintaining biodiversity. However, previous studies have only focused on suitable distribution areas for species and not on the distribution of plant associations. Larix gmelinii is a sensitive and abundant species that occurs along the southern margin of the Eurasian boreal forests, and its distribution is closely related to permafrost. In this study, 420 original plots of L. gmelinii forests were investigated. We used a Maxent model and the ArcGIS software to project the potential geographical distribution of L. gmelinii associations in the future (by 2050 and 2070) according to the climate scenarios RCP 2.6, RCP 4.5, and RCP 8.5. We used the multi‐classification logistic regression analysis method to obtain the response of the suitable area change for the L. gmelinii alliance and associations to climate change under different climate scenarios. Results revealed that temperature is the most crucial factor affecting the distribution of L. gmelinii forests and most of its associations under different climate scenarios. Suitable areas for each association type are shrinking by varying degrees, especially due to habitat loss at high altitudes in special terrains. Different L. gmelinii associations should have different management measures based on the site conditions, composition structure, growth, development, and renewal succession trends. Subsequent research should consider data on biological factors to obtain more accurate prediction results.

Prediction of potential distribution of soybean in the frigid region in China with MaxEnt modeling

Soybean (Glycine max (L.) Merr.) is one of the most important grains and oil-producing plants grown in China. Understanding the potential suitable characteristics of areas where soybean is grown and predicting its potential habitat under different climate scenarios are a significant part of ensuring food security. This study compiled 65 occurrence locations of soybean and 32 environmental variables obtained from the WorldClim database. Nine environmental variables were selected for model training. We identified potential suitable distribution areas for soybean in the frigid region and predicted changes in its geographical distribution under four shared socioeconomic pathways, SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5, for the periods from 2021 to 2040, 2041 to 2060, 2061 to 2080, and 2081 to 2100 using the MaxEnt model. The results showed that annual mean temperature, elevation, and April solar radiation were the dominant factors affecting the distribution of soybean, contributing 48.8%, 17.9%, and 15.7% of the variability in the data, respectively. Highly suitable habitats (defined as having a suitability variable P of 0.66–1.0) for the current conditions included the Songnen and Sanjiang plains, covering about 2.36 × 105 km2. The total areas of highly (as defined above) and moderately suitable (0.33–0.66) habitats would be reduced under the four climate scenarios. However, the centroids of the highly suitable habitat had a small mobile range under different scenarios. These results along with previous research on the potential distribution of soybean offer useful information; ecological modeling approaches need to be considered in future crop planting management and land use.

Prediction of Suitable Distribution Area of Plateau pika (Ochotona curzoniae) in the Qinghai–Tibet Plateau under Shared Socioeconomic Pathways (SSPs)

The Qinghai–Tibet Plateau is one of the regions most strongly affected by climate change. The climate feedback of the distribution of plateau pika, a key species, is closely related to the trophic structure of the plateau ecosystem and the development of agriculture and animal husbandry on the plateau. In order to understand the impact of future climate change on the suitable distribution area of plateau pika, potential suitable distribution areas of Plateau pika were predicted using the MaxEnt model under three climate scenarios (SSP 1-2.6, SSP 2-4.5, and SSP 5-8.5) in the near term (2021–2040) and medium term (2041–2060). The predictions were found to be highly accurate with AUC values of 0.997 and 0.996 for the training and test sets. The main results are as follows: (1) The precipitation of the wettest month (BIO 16), mean diurnal range (BIO 2), slope, elevation, temperature seasonality (BIO 4), and annual mean temperature (BIO 1) were the main influencing factors. (2) In the historical period, the total suitable distribution area of Plateau pika in the Qinghai–Tibet Plateau accounted for 29.90% of the total area at approximately 74.74 × 104 km2, concentrated in the eastern and central areas of the Qinghai–Tibet Plateau. (3) The total suitable distribution area of pika exhibited an expansion trend under SSP 1-2.6 and SSP 2-4.5 in the near term (2021–2040), and the expansion area was concentrated in the eastern and central parts of the Qinghai–Tibet Plateau. The expansion area was the largest in Qinghai Province, followed by Sichuan Province and Tibet. In contrast, the suitable distribution area shrank in the Altun Mountains, Xinjiang. Under SSP 5-8.5 in the near term and all scenarios in the medium term (2041–2060), the suitable distribution area of Plateau pika decreased to different degrees. The shrinkage area was concentrated at the margin of the Qaidam Basin, central Tibet, and the Qilian Mountains in the east of Qinghai Province. (4) Plateau pika migrated toward the east or southeast on the Qinghai–Tibet Plateau under the three climate scenarios. Under most of the scenarios, the migration distance was longer in the medium term than in the near term.

Analysis on the hotspot characteristics of bird diversity distribution along the continental coastline of China

Global climate change and disturbances from human activities lead to habitat loss and changes in habitat quality, resulting in a reduction in biodiversity. The continental coastline of China distributes some cities with highly developed economies and coastal wetlands with rich biodiversity, and both economic development and biodiversity conservation are important topics. In order to clarify the spatial distribution of bird biodiversity in coastal areas, based on the MaxEnt model and GIS spatial analysis, the distribution data of 488 species of birds and 15 environmental variables were used to simulate the suitable distribution areas of birds, and to analyze the spatial distribution and hotspots of bird biodiversity in coastal areas. The main findings of this study are as follows. (1) A total of 488 species in 249 genera of 21 orders and 81 families of birds were involved in the modeling of coastal areas. The main environmental factors affecting the potential distribution of birds in general are: land use, monthly mean diurnal temperature range, and precipitation of the driest month. (2) High value areas of bird richness are distributed in different locations in the four sea areas: In the Bohai Rim region, they are mainly distributed in the Liaohe Estuary Wetland in Liaoning Province, the vicinity of the Yongdingxin River and Haihe River in Tianjin, the eastern part of Tianjin, and the Yellow River and Yellow River Delta Wetland in Shandong Province; In the coastal area of the Yellow Sea, they are primarily found in Kunyu Mountain National Nature Reserve, Laoshan Provincial Nature Reserve in Shandong Province, and Yancheng Wetland Rare Birds National Nature Reserve in Jiangsu Province; In the coastal areas of the East China Sea, they are mainly found at the mouth of the Yangtze River, at the national nature reserve of Dongtan birds on Chongming Island, along the southeastern coast of Zhejiang Province, near the Min River and along the coast of Quanzhou in Fujian Province; In the coastal areas of the South China Sea, they are mainly distributed in the Pearl River Delta wetlands of Guangdong Province, the southeastern coastal areas of the Guangdong-Hong Kong-Macao Greater Bay Area, and the Shiwanda Mountain National Nature Reserve in Guangxi Province. (3) The spatial trends in the distribution of hotspots of birds of national priority protection in coastal areas are generally consistent, but more concentrated than the distribution of all birds. (4) After the high-value areas of bird richness were superimposed with protected areas, it was found that the intersecting area accounted for a small proportion of the protected area, and many areas near the inland had low bird richness. Finally, the findings provide references for bird biodiversity conservation and planning in coastal areas.

Predicting the Potential Suitable Distribution of Larix principis-rupprechtii Mayr under Climate Change Scenarios

Larix principis-rupprechtii Mayr (larch) is a native conifer species in North China, and also a major silvicultural and timber species in the region. Climate change has led to a change in its suitable distribution area. However, the dominant factors affecting changes in its suitable distribution and migration trends are not clear. In this study, based on forest resource inventory data and bioclimatic data in Hebei and Shanxi provinces, China, we built an ensemble model based on seven algorithms to simulate the larch’s potential suitable distribution areas under three shared socioeconomic pathways (SSPs: SSP1-2.6, SSP2-4.5, and SSP5-8.5) for the current and future (2021–2040, 2041–2060 and 2080–2100). The results revealed that: (1) ensemble models significantly improved the predictive accuracy (ROC = 0.95, TSS = 0.81, KAPPA = 0.65); (2) the current potentially suitable distribution area was concentrated in the Bashang Plateau and the northwestern mountain range of the study area. Among them, 12.38% were highly suitable distribution areas, 12.67% were moderately suitable distribution areas, and 12.01% were lowly suitable distribution areas; (3) the main climatic factors affecting larch distribution were mean temperature of driest quarter, mean diurnal range, precipitation of warmest quarter, and temperature annual range; (4) under different future climate scenarios, the contraction of the suitable distribution area of larch increased significantly with increasing SSP radiation intensity. By 2100, the suitable distribution area of larch was expected to decrease by 26.5% under SSP1-2.6, 57.9% under SSP2-4.5, and 75.7% under SSP5-8.5 scenarios; (5) from 2021 to 2100, the different suitable distribution areas of larch showed a trend of migration to the northeast. Under the SSP5-8.5 scenario, the migration distance of different suitable distribution areas was the largest, in which the high suitable distribution area migrated 232.60 km, the middle suitable distribution area migrated 206.75 km, and the low suitable distribution area migrated 163.43 km. The results revealed the impact of climate change on the larch distribution, which provided a scientific basis for making forest management decisions.

Ecological Niche Overlap and Prediction of the Potential Distribution of Two Sympatric Ficus (Moraceae) Species in the Indo-Burma Region

Climate change is a major factor influencing the species distribution and population diversity of living creatures. In this study, the ecological niche model (ENM) MaxEnt was used to evaluate habitat suitability and predict potential habitats of two sympatric fig species, i.e., Ficus squamosa and F. heterostyla, in the Xishuangbanna region of China. Results indicated that mean diurnal range, isothermality, cation exchange capacity (at pH 7), and temperature seasonality were key variables influencing habitat suitability for F. squamosa. However, temperature seasonality and precipitation of the driest quarter showed the greatest contributions to F. heterostyla distribution. During the current period, the habitat suitability distributions of both Ficus species were considerably higher than known occurrences. In the future, potentially suitable distribution areas for both species will reduce overall across the whole study area, although some expansion may occur by 2070. Niche overlap of suitable areas for both species was initially high and then declined in the current period and future epochs in the RCP 2.6 scenario, but increased in the RCP 8.5 scenario. In short, the responses of both Ficus species to climate change differed. Thus, specific actions such as ex situ conservation and assisted migration may be needed to conserve both species.

Status, mechanism, suitable distribution areas and protection countermeasure of invasive species in the karst areas of Southwest China

Biological invasion is one of the major threats to global biodiversity attracting a primary focus of scientific attention. During the past decades, due to the diversity and peculiarity of species, coupled with the vulnerable ecosystem, karst areas have received more and more attention. Numerous investigations and studies have confirmed that the karst areas in Southwest China are suffering from biological invasions under the intensified human activities and the climate change they caused. Despite some fundamental research on invasive species that has been conducted to understand the species and distribution in the karst areas, the mechanism of biological invasions and the response of karst ecosystem are still lack sufficient knowledge. In this paper, we summarized the habitat characteristics and invasion status of karst areas to biological invasions. This paper comprehensively analyzed the research results on biological invasions in karst areas to understand the status and development trends of biological invasions in the karst of China, so as to promote the relevant research on biological invasions in the karst areas. We found that the biological invasions in the karst areas were increasing with years. We also revealed the possible mechanism including competition, mutualism, allelopathy and phenotypic plasticity of biological invasion in karst by summarizing the relevant research results of in the karst areas. Moreover, the response of karst to biological invasion was described from the aspects of ecosystem, community, species and genetic levels, etc. By comparing the characteristics of invasive species that have been found in karst area, we analyzed the common characteristics including strong fecundity and rapid growth rate, strong environmental adaptability, strong phenotypic plasticity and high genetic diversity of the existing invasive species, we simulated and predicted the habitat of invasive species. Overall, we found three areas with high habitat suitability covering Chinese southwest Karst ecosystem, which include the southern Yunnan-Guizhou Plateau, foothill area on the Min-Yue-Gui and foothill area of southern Yunnan. It is also worth noting that the Sichuan Basin has a higher invasive risk compared to its surrounding Karst ecosystem, mainly because of the high habitat suitability of some invasive species. Therefore, we suggest that a general survey of alien invasive species in the karst areas of Southwest China should be carried out as soon as possible, focusing on the survey of the suitable areas of alien species for early warning. In addition, to establish a database of invasive alien species in the karst areas of southwest China, strengthen the monitoring of alien species, and evaluate the impact of invasive species in key areas on the biodiversity and ecosystem in the karst areas of Southwest China, so as to maintain the stability of cave biodiversity and the fragile ecosystem.

Predicted changes in the distribution of Antarctic krill in the Cosmonaut Sea under future climate change scenarios

Antarctic krill (Euphausia superba) are the key species of the ecological system in the Cosmonaut Sea. Long-term habitat alterations in krill due to climate change have been considered in recent decades. However, there is still a lack understanding about krill distribution. The MaxEnt model was used to forecast the suitable distribution area of krill for this study, which is based on data from the Coupled Model Intercomparison Project in its sixth phase (CMIP6) in the near future and far future. A total of 145 occurrence points and 15 environmental factors were selected to build the MaxEnt model. The current suitable habitat regions for krill were mostly detected in the western and central regions of the Cosmonaut Sea, which accounted for 10.07% of the total area. The most important environmental variables that influenced krill distribution were minimum surface solar radiation downward (ssrdmin), the mean temperature (tem) and the mean northward velocity (v). In the near future and far future, the suitable area of krill was seen to decline under all shared socioeconomic pathways (SSPs), with the smallest reduction under SSP1-2.6 and the greatest reduction under SSP5-8.5. The suitable area for krill dropped quicker from the near future to the far future than the present to the near future. Krill habitats were expected to shift to the poles. The tem continued to rise in the future under all SSP scenarios, particularly under the high radiative forcing scenario. The increase in water temperature is the main reason for the decrease in suitable areas for Antarctic krill. Our results show the future distribution of krill in the future and provide a reasonable reference for the ecological protection policy of the Cosmonaut Sea.