不同SSP-RCP情景下中国生态系统服务价值评估

定量评估生态系统服务价值是人类合理利用和管理生态系统的重要依据,未来气候情景下土地利用变化模拟及其对生态系统服务价值的影响评估对于区域生态系统服务管理、开展生态功能区划及减缓和适应气候变化等方面具有重要意义。基于最新IPCC共享社会经济路径(SSPs)和典型浓度路径(RCPs)的科学组合情景模拟得到的土地利用情景数据,对2020—2050年我国生态系统服务价值进行估算,并对2050年生态系统服务间的权衡与协同关系进行讨论,主要得到以下结论：生态系统服务价值(ESV)在2020—2050年表现为SSP1-RCP2.6>SSP2-RCP4.5>SSP3-RCP6.0,SSP1-RCP2.6情景下2020年ESV为12.39×10⁴亿元,2050年ESV为12.34×10⁴亿元;SSP2-RCP4.5情景下2020年ESV为12.17×10⁴亿元,2050年ESV为12.11×10⁴亿元;SSP3-RCP6.0情景下2020年ESV为12.02×10⁴亿元,2050年ES...     

Will climate change affect ectoparasite species ranges?

Aim  Over the next 100 years, human-driven climate change and resulting changes in species occurrences will have global impacts on biodiversity, ecosystem function, and human health. Here we examine how climate change may affect the occurrences of tick species in Africa and alter the suitability of habitat outside Africa for African ticks.
Location  Africa and the world.
Methods  We predicted continental and global changes in habitat suitability for each of 73 African tick species, using multiple regression models in different climate change scenarios that cover a wide range of uncertainty.
Results  Global habitat suitability improves for nearly all tick species under each of a representative range of eight climate change scenarios. Depending on the scenario, African tick species experience an average increase in global habitat suitability of between 1 million and 9 million square kilometres between 1990 and 2100.
Main conclusions  The potential for successful translocations of ticks and their pathogens from Africa to the rest of the world is likely to increase over the next 100 years. Although the general trend is one of range expansion, there are winners and losers among tick species in each scenario, suggesting that tick community composition will be disrupted substantially by climate change. If this is also typical of other invertebrates, then climate change will disrupt not only the geographic location of communities but also their structure. Changes in tick communities are also likely to influence tick-borne pathogens.     

Pattern of Tick Aggregation on Mice: Larger Than Expected Distribution Tail Enhances the Spread of Tick-Borne Pathogens

The spread of tick-borne pathogens represents an important threat to human and animal health in many parts of Eurasia. Here, we analysed a 9-year time series of Ixodes ricinus ticks feeding on Apodemus flavicollis mice (main reservoir-competent host for tick-borne encephalitis, TBE) sampled in Trentino (Northern Italy). The tail of the distribution of the number of ticks per host was fitted by three theoretical distributions: Negative Binomial (NB), Poisson-LogNormal (PoiLN), and Power-Law (PL). The fit with theoretical distributions indicated that the tail of the tick infestation pattern on mice is better described by the PL distribution. Moreover, we found that the tail of the distribution significantly changes with seasonal variations in host abundance. In order to investigate the effect of different tails of tick distribution on the invasion of a non-systemically transmitted pathogen, we simulated the transmission of a TBE-like virus between susceptible and infective ticks using a stochastic model. Model simulations indicated different outcomes of disease spreading when considering different distribution laws of ticks among hosts. Specifically, we found that the epidemic threshold and the prevalence equilibria obtained in epidemiological simulations with PL distribution are a good approximation of those observed in simulations feed by the empirical distribution. Moreover, we also found that the epidemic threshold for disease invasion was lower when considering the seasonal variation of tick aggregation.     

中国柯属5种资源植物潜在地理分布及其对气候变化的响应

利用最大墒模型和地理信息系统软件对柯属（Lithocarpus）5种资源植物在我国的适宜分布区进行了定量预测,并对未来不同气候情景下其分布区的变化进行了分析。结果显示：木姜叶柯（L.litseifolius（Hance）Chun.）在我国秦岭淮河以南广泛分布,短尾柯（L.brevicaudatus（Skan）Hay.）主要分布在我国亚热带中东部区域;木姜叶柯在未来气候（2061-2080年）RCP2.6、RCP8.5两种情景下适生区面积分别减少了5.1%和3.0%,而短尾柯却分别增加了0.5%和1.5%。白柯（L.dealbatus（Hook.f.et Thoms.ex DC.）Rehd.）适宜区主要分布在云南北部、四川南部,烟斗柯（L.corneus（Lour.）Rehd.）主要分布在两广省份的南亚热带地区。白柯和烟斗柯在RCP2.6情景下适生区面积分别减少了12.1%和17.8%,在RCP8.5情景下分别减少了3.5%和15.9%,这两个种的适宜区面积减少较多。厚斗柯（L.elizabethae（Tutch.）Rehd.）主要分布于广西,在两种情景下适宜区面积分别增加了7.3%和6.3%。研究结果表明,由于分布区存在差异,同属不同物种的未来分布对气候变化的响应不同。     

Predicted changes in the potential distribution of seerfish (Scomberomorus sierra) under multiple climate change scenarios in the Colombian Pacific Ocean

Some projections predict that fishery resources in tropical areas will be negatively affected by climate change, resulting in the displacement of species and reducing their availability for fishing. In this study, the potential geographic distribution of Scomberomorus sierra under current conditions in the Colombian Pacific Ocean was simulated using maximum entropy (MaxEnt) modeling software, based on species presence data and satellite-derived environmental variables (Sea Surface Temperature (SST), Chlorophyll-a and bathymetry). The future distributions of S. sierra in 2020s (short term) and 2080s (long term) were projected under the RCP 2.6 and 8.5 scenarios for four ensembled global circulation models (GCM) obtained from the Coupled Model Intercomparison Project Phase 5 (CMIP5). The current and future geographical distributions were modeled for the species' fishing months (November to April), and pixel-wise change distribution and core shift were determined. The results indicated good performance for the distribution models in the present and future scenarios (AUC > 0.9). The RCP 8.5 scenario, in both, the short and long term, indicated the highest adverse changes in the species distribution. The distribution core shift indicates that under RCP 2.6 in the 2020s for November and December, the shift is towards the central zone of the Colombian Pacific. In the 2080s (long term), the distribution centroid tends to move towards the central zone, further from the coastline. Results also showed the same change tendency for RCP 8.5 in both the 2020s and 2080s. This is one of the first studies that elucidate the effects of climate change on a commercial species in the Colombian Pacific. The results give an insight into future management strategies for seerfish fisheries, which can also be used as a reference for studying other species.     

Influence of the Biotope on the Tick Infestation of Cattle and on the Tick-Borne Pathogen Repertoire of Cattle Ticks in Ethiopia

Background

The majority of vector-borne infections occur in the tropics, including Africa, but molecular eco-epidemiological studies are seldom reported from these regions. In particular, most previously published data on ticks in Ethiopia focus on species distribution, and only a few molecular studies on the occurrence of tick-borne pathogens or on ecological factors influencing these. The present study was undertaken to evaluate, if ticks collected from cattle in different Ethiopian biotopes harbour (had access to) different pathogens.

Methods

In South-Western Ethiopia 1032 hard ticks were removed from cattle grazing in three kinds of tick biotopes. DNA was individually extracted from one specimen of both sexes of each tick species per cattle. These samples were molecularly analysed for the presence of tick-borne pathogens.

Results

Amblyomma variegatum was significantly more abundant on mid highland, than on moist highland. Rhipicephalus decoloratus was absent from savannah lowland, where virtually only A. cohaerens was found. In the ticks Coxiella burnetii had the highest prevalence on savannah lowland. PCR positivity to Theileria spp. did not appear to depend on the biotope, but some genotypes were unique to certain tick species. Significantly more A. variegatum specimens were rickettsia-positive, than those of other tick species. The presence of rickettsiae (R. africae) appeared to be associated with mid highland in case of A. variegatum and A. cohaerens. The low level of haemoplasma positivity seemed to be equally distributed among the tick species, but was restricted to one biotope type.

Conclusions

The tick biotope, in which cattle are grazed, will influence not only the tick burden of these hosts, but also the spectrum of pathogens in their ticks. Thus, the presence of pathogens with alternative (non-tick-borne) transmission routes, with transstadial or with transovarial transmission by ticks appeared to be associated with the biotope type, with the tick species, or both, respectively.     

Severe Rhipicephalus sanguineus tick infestation in a home from rural area of Nanchang in China

On October 13, 2021, a tick infestation occurred in a home in rural area of Nanchang city, China, and we were asked to inspect the tick infestation. Ticks were collected in the largest number on courtyard door jambs, followed by living room and bedroom door jambs. Ticks were identified morphologically as Rhipicephalus sanguineus adults. The 16S rRNA analysis effectively distinguished the ticks in this study from other Rhipicephalus species, including R. sanguineus south-east, temperate and tropical lineages and identified genetically as R. sanguineus south China lineage. Tick samples were subjected to conventional PCR analysis and detected negative for the presence of tick-borne pathogens. Our findings indicate that there was low transmission risk of tick-borne pathogens to humans in the tick-infested home. Further studies are needed to proactively investigate the tick species in Nanchang, and determine the presence of tick-borne pathogens for assessing their threat to human health in the region.     

Comparison of tick-borne microorganism communities in Ixodes spp. of the Ixodes ricinus species complex at distinct geographical regions

Characterizing the tick-borne microorganism communities of Ixodes ricinus (sheep tick) and Ixodes persulcatus (taiga tick) from the I. ricinus species complex in distinct geographical regions of Eastern Europe and European Russia, we demonstrated differences between the two ticks. Taiga ticks were more frequently mono- and co-infected than sheep ticks: 24.4 % (45/184 tested ticks) versus 17.5 % (52/297) and 4.3 % (8/184) versus 3.4 % (10/297), respectively. Ginsberg co-infection index values were significant at the various sites. Diversity of the tick-borne microorganism communities was estimated by the Shannon index, reaching values of 1.71 ± 0.46 and 1.20 ± 0.15 at the sheep-tick and the taiga-tick harbored sites, respectively. Richness of the tick-borne microorganism community in the sheep tick collection sites was about twice the value of the taiga tick collection sites. Future investigations are warranted to further characterize the peculiarities of the tick-borne microorganism communities among the ticks of the Ixodes ricinus complex.     

Molecular Detection of Tick-Borne Pathogens in Humans with Tick Bites and Erythema Migrans,in the Netherlands

BackgroundTick-borne diseases are the most prevalent vector-borne diseases in Europe. Knowledge on the incidence and clinical presentation of other tick-borne diseases than Lyme borreliosis and tick-borne encephalitis is minimal, despite the high human exposure to these pathogens through tick bites. Using molecular detection techniques, the frequency of tick-borne infections after exposure through tick bites was estimated.MethodsTicks, blood samples and questionnaires on health status were collected from patients that visited their general practitioner with a tick bite or erythema migrans in 2007 and 2008. The presence of several tick-borne pathogens in 314 ticks and 626 blood samples of this cohort were analyzed using PCR-based methods. Using multivariate logistic regression, associations were explored between pathogens detected in blood and self-reported symptoms at enrolment and during a three-month follow-up period.ResultsHalf of the ticks removed from humans tested positive for Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Candidatus Neoehrlichia mikurensis, Rickettsia helvetica, Rickettsia monacensis, Borrelia miyamotoi and several Babesia species. Among 92 Borrelia burgdorferi s. l. positive ticks, 33% carried another pathogen from a different genus. In blood of sixteen out of 626 persons with tick bites or erythema migrans, DNA was detected from Candidatus Neoehrlichia mikurensis (n = 7), Anaplasma phagocytophilum (n = 5), Babesia divergens (n = 3), Borrelia miyamotoi (n = 1) and Borrelia burgdorferi s. l. (n = 1). None of these sixteen individuals reported any overt symptoms that would indicate a corresponding illness during the three-month follow-up period. No associations were found between the presence of pathogen DNA in blood and; self-reported symptoms, with pathogen DNA in the corresponding ticks (n = 8), reported tick attachment duration, tick engorgement, or antibiotic treatment at enrolment.ConclusionsBased on molecular detection techniques, the probability of infection with a tick-borne pathogen other than Lyme spirochetes after a tick bite is roughly 2.4%, in the Netherlands. Similarly, among patients with erythema migrans, the probability of a co-infection with another tick-borne pathogen is approximately 2.7%. How often these infections cause disease symptoms or to what extend co-infections affect the course of Lyme borreliosis needs further investigations.     

人参潜在地理分布以及气候变化对其影响预测

本文以人参为研究对象,基于人参分布点位数据和22个气候环境因子数据,运用BioMod2平台10个物种分布模型对当前我国东北地区人参潜在生境分布进行预测.以受试者工作特征曲线(ROC)为权重集成10个模型的模拟结果,构建组合模型,并基于该模型预测了IPCC 第五次评估报告中RCP 8.5、RCP 6.0、RCP 4.5和RCP 2.6等4种排放情景下21世纪50和70年代人参潜在分布范围.结果表明: 在基准气候条件下,人参适宜生境面积占研究区总面积的10.4%,此类地区主要分布于研究区东北部长白山地区以及小兴安岭东南部区域的森林地带.在未来不同的排放情景下研究区人参的适宜生境变化显著,总体上分布范围将有一定程度的缩小.同时参与建模的10种模型在统计学精度、预测结果以及变量权重上都有差异.模型精度计算结果表明,MAXENT模拟效果最好,GAM、RF和ANN次之,SRE模拟精度最低.本文构建的组合模型在一定程度上提高了现有物种分布模型的预测精度,从而使模拟效果更优.     

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.     

Cattle ticks of the genera <Emphasis Type="Italic">Rhipicephalus</Emphasis> and <Emphasis Type="Italic">Amblyomma</Emphasis> of economic importance in Tanzania: distribution assessed with GIS based on an extensive field survey

In order to implement a robust integrated tick and tick-borne disease control programme in Tanzania, based on ecological and epidemiological knowledge of ticks and their associated diseases, a national tick and sero-surveillance study was carried out in all 21 regions of the mainland, as well as on Mafia Island, between 1998 and 2001. The current distributions of Rhipicephalus appendiculatus, R. pravus, Amblyomma variegatum, A. gemma, and A. lepidum are illustrated and discussed. Tick distribution maps were assessed using the Weights-of-Evidence method (WofE), and employing temperature, humidity, NDVI, rainfall, and land-cover predictive data. Ground-truthing was done to check correspondence both of the data employed in prediction with land-cover characteristics discerned in the field as well as of the surveyed and predicted tick distributions. Statistical methods were used to analyse associations of the tick species with their environment, cattle density, and other ticks. Except for R. appendiculatus, no appreciable changes were demonstrated in the predicted and observed tick distributions compared to the existing maps that originated in the 1950–1960s. Cattle density influenced the distribution of A. variegatum and, to a certain extent, of A. lepidum, but had no appreciable influence on the distribution of any of the other ticks discussed in this paper, neither did livestock movement. Distinct differences for environmental requirements where observed between different tick species within the same genus. The predictive maps of R. appendiculatus and R. pravus suggest their mutually exclusive distribution in Tanzania, and simultaneous statistical analysis showed R. pravus as a greater specialist. Of the three Amblyomma species, A. variegatum is the most catholic tick species in Tanzania, while both A. gemma and A. lepidum belong to the more specialized species. Despite dissimilar habitat preferences, all three Amblyomma spp. co-exist in central Tanzania, where very heterogeneous habitats may simultaneously satisfy the environmental requirements of all three species. The current study, conducted about 4 decades after the last major survey activities, has shown that changing livestock policies, unrestricted livestock movement and a continuous change in climatic/environmental conditions in Tanzania have brought about only limited changes in the distribution patterns of R. appendiculatus, R. pravus and the three Amblyomma species investigated. Whether this observation indicates a relative indifference of these ticks to environmental and/or climate changes allows room for speculation.     

Using habitat models to map diversity: pan-African species richness of ticks (Acari: Ixodida)

Aims To show how logistic regression models for individual species can be used to produce improved estimates of species richness at a continental scale; to present these data for African ticks (Acari: Ixodida); and to address the question of whether there is a latitudinal gradient in tick species richness. Location Africa. Methods A database of 34,060 collection records for African ticks is used to produce a pan‐African map of known tick species richness at 0.25 × 0.25‐degree resolution. The likely distributions of seventy‐three species are then estimated from environmental factors using logistic regression, and localities where there is a suitably high probability of occurrence for a given species are added to the original data for that species. These augmented data are combined to produce a map of the predicted pan‐African distribution of tick species richness. The relationship of species richness to latitude is considered along a transect placed across some of the more extensively collected areas. Results Maps of known and predicted pan‐African tick species richness are presented, and deficiencies in the available data are highlighted. Correlations using both known and predicted estimates of tick species richness suggest that ticks follow similar species richness patterns to those described for African mammals and birds, with a latitudinal gradient and highest species richness in east equatorial Africa. Tick species ranges are log‐normally distributed. Main conclusions Carefully constructed probability surfaces offer a more powerful approach to mapping species ranges than simple presence‐absence maps. Such models are a useful extension to current biogeographical methods and have a wide range of potential applications in ecology, epidemiology and conservation. Tick species richness at a continental scale follows similar trends to those reported for mammals and birds.     

Ticks (Acari: Ixodida) infesting humans in the provinces of Kelkit Valley, a Crimean-congo hemorrhagic fever endemic region in Turkey

Ticks are mandatory blood feeding ectoparasites leading transmission of various tick-borne pathogens to human and animals. Since 2002, thousands of human tick bites and numerous Crimean-Congo Hemorrhagic Fever cases have been reported in several provinces in the Kelkit Valley region in Turkey. Despite increased cases of tick bites and tick-borne diseases, no taxonomic information is available about the tick species infesting humans in the region. In the present study, a tick survey on humans was performed to determine the species composition of ticks infesting humans in several provinces of Kelkit Valley. In the survey, 1,460 ticks (721 males, 516 females and 223 nymphs) were collected from tick-infested humans. A total of 19 tick species have been found on humans in the region, including 7 Hyalomma, 2 Argas, 2 Haemaphysalis, 2 Ixodes, Dermacentor and 3 Rhipicephalus species. Infestation of Dermacentor reticulatus on humans was documented for the first time in Turkey.     

Tracing the future of epidemics: Coincident niche distribution of host animals and disease incidence revealed climate-correlated risk shifts of main zoonotic diseases in China

Climate has critical roles in the origin, pathogenesis and transmission of infectious zoonotic diseases. However, large-scale epidemiologic trend and specific response pattern of zoonotic diseases under future climate scenarios are poorly understood. Here, we projected the distribution shifts of transmission risks of main zoonotic diseases under climate change in China. First, we shaped the global habitat distribution of main host animals for three representative zoonotic diseases (2, 6, and 12 hosts for dengue, hemorrhagic fever, and plague, respectively) with 253,049 occurrence records using maximum entropy (Maxent) modeling. Meanwhile, we predicted the risk distribution of the above three diseases with 197,098 disease incidence records from 2004 to 2017 in China using an integrated Maxent modeling approach. The comparative analysis showed that there exist highly coincident niche distributions between habitat distribution of hosts and risk distribution of diseases, indicating that the integrated Maxent modeling is accurate and effective for predicting the potential risk of zoonotic diseases. On this basis, we further projected the current and future transmission risks of 11 main zoonotic diseases under four representative concentration pathways (RCPs) (RCP2.6, RCP4.5, RCP6.0, and RCP8.5) in 2050 and 2070 in China using the above integrated Maxent modeling with 1,001,416 disease incidence records. We found that Central China, Southeast China, and South China are concentrated regions with high transmission risks for main zoonotic diseases. More specifically, zoonotic diseases had diverse shift patterns of transmission risks including increase, decrease, and unstable. Further correlation analysis indicated that these patterns of shifts were highly correlated with global warming and precipitation increase. Our results revealed how specific zoonotic diseases respond in a changing climate, thereby calling for effective administration and prevention strategies. Furthermore, these results will shed light on guiding future epidemiologic prediction of emerging infectious diseases under global climate change.     

Effects of climate change on the distribution of wild Akebia trifoliata

Understanding the impacts and constraints of climate change on the geographical distribution of wild Akebia trifoliata is crucial for its sustainable management and economic development as a medicinal material or fruit. In this study, according to the first‐hand information obtained from field investigation, the distribution and response to climate change of A. trifoliata were studied by the MaxEnt model and ArcGIS. The genetic diversity and population structure of 21 natural populations of A. trifoliata were studied by simple sequence repeat (SSR) markers. The results showed that the most important bioclimatic variable limiting the distribution of A. trifoliata was the Mean Temperature of Coldest Quarter (bio11). Under the scenarios SSP1‐2.6 and SSP2‐4.5, the suitable area of A. trifoliata in the world will remain stable, and the suitable area will increase significantly under the scenarios of SSP3‐7.0 and SSP5‐8.5. Under the current climate scenario, the suitable growth regions of A. trifoliata in China were 79.9–122.7°E and 21.5–37.5°N. Under the four emission scenarios in the future, the geometric center of the suitable distribution regions of Akebia trifoliata in China will move to the north. The clustering results of 21 populations of A. trifoliata analyzed by SSR markers showed that they had a trend of evolution from south to north.     

Nowhere to go: Potential distribution shifts of a widespread lizard under two climate change scenarios

Species range shifts under climate change scenarios are caused by many factors. An integrative approach combining demographic distribution models (DDMs) and correlative models can provide key information for making accurate predictions, especially for widespread species occupying diverse environments. Sceloporus grammicus is a lizard that occurs widely in North America and shows variation in its life history traits among environments. Here we assessed future changes in the distribution of S. grammicus in Mexico using mechanistic, correlative, and hybrid models, under two (RCP 4.5 and RCP 8.5) contrasting climate change scenarios, based on two General Circulation Models (GCM: ACCESS 1.0 and MIROC5). We measured the snout-vent length (SVL) of individuals of S. grammicus from 11 populations from central Mexico and input this trait as an indicator of vital rates into integral projection models (IPMs). We used the IPMs to calculate the growth rate (λ) of each population; we then modeled λ as a function of temperature to project λ across a temperature raster layer of Mexico. The correlative models were built using occurrence records of S. grammicus and the key environmental variables. For each scenario and GCM, we first built a map that displayed λ values (> 0.9) across the country; we then built a map that showed habitat suitability probability. We then overlaid the results of these two maps to build a map displaying presence/absence. In general, the results revealed that sites with high habitat suitability probability and λ > 0.9 will decrease under both climate change scenarios, with the decrease being more severe in the RCP 8.5 scenario compared to the RCP 4.5 scenario. Outputs were similar for all projections. Our results predict a range contraction to higher and cooler places such as mountainous zones and were more restrictive under the hybrid approach. The use of this hybrid approach can overcome the weaknesses of correlative models and DDMs. This is the first study to project a range contraction for this species, and the results are consistent with previous observations of other species exhibiting distributional shifts towards the poles or upwards in elevation as the climate warms. However, S. grammicus may overcome the negative effects of climate change via its plasticity in habitat use, thermal preferences, and life history traits.     

CLIMEX simulated predictions of the potential distribution of Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) considering the northern boundary: With special emphasis on Jeju,Korea

The global climate change has led to the distribution of Bactrocera dorsalis from its origin in Southeast Asia to mainland China, which is situated at latitudes similar to Jeju Island, South Korea. In order to evaluate the establishment of B. dorsalis in Korea, it is necessary to determine the climate suitability. When the parameters of CLIMEX model were adjusted to include Wuhan region in China as the northern limit, the model outputs explained well the distribution and occurrence characteristics (namely the annual number of generations) of B. dorsalis in major distribution regions in the world. In IPCC/RCP 8.5 scenario, the establishment of B. dorsalis was suitable to a small part of Jeju Island in the 2010s. The range might gradually spread until the 2090s, with many parts of the lowlands of Jeju Island being marginal to optimal in suitability. The present CLIMEX model with parameters that adjusted to known northern limit will be useful for annual risk mapping to facilitate a monitoring system for early detection of a possible founder population of B. dorsalis in Jeju, South Korea.     

不同气候条件下沙冬青属植物在我国的潜在分布——基于生态位模型预测

沙冬青属（Ammopiptanthus）植物是古地中海第三纪孑遗濒危物种,包括沙冬青（Ammopiptanthus mgolicus）和矮沙冬青（Ammopiptanthus nanus）,主要分布在我国西北干旱、半干旱地区,其不仅具有较高的研究价值,同时对我国西北干旱地区生态环境具有十分重要的作用。近年来由于全球气候变化及人为干扰等因素,沙冬青属植物天然分布面积骤缩,濒临灭绝。本研究利用MaxEnt模型、Bioclim模型和Domain模型对沙冬青属植物在我国末次间冰期（Last Interglacial）、末次冰盛期（Last Glacial Maximum）、当代和2050年（RCP4.5和RCP8.5）4个时期气候情景下的潜在适生区进行预测。结果表明：MaxEnt模型对沙冬青属植物潜在分布区的预测具有极高的准确度,所有模型的平均受试者工作特征曲线下面积（AUC测试值）均高于0.80。当代沙冬青最佳及高适生区占全国总面积的2.78%,主要集中在内蒙古中部、宁夏北部和甘肃北部等地;未来沙冬青最佳及高适生区在现有分布范围呈现向外扩张的趋势,主要分布在内蒙古鄂托克旗、鄂尔多斯、阿拉善左旗、宁夏吴忠和甘肃民勒县等地。当代矮沙冬青最佳及高适生区占全国总面积的2.23%,主要集中在新疆南部;未来矮沙冬青最佳及高适生区向新疆乌恰县南部、乌鲁木齐北部移动和扩大,主要分布在新疆乌恰县、乌苏市、吐鲁番市和乌鲁木齐市。未来2050年（RCP4.5和RCP8.5）两种气候情景下沙冬青和矮沙冬青的潜在分布总面积均有所增加,与当代相比变化不明显,但不同适生等级的潜在分布面积变化较大,在更高的CO₂排放量（RCP8.5）情景下沙冬青和矮冬青的最佳及高适生区范围的预测结果都将减少。从气候因素角度考虑,研究表明未来气候情景下沙冬青属植物的适生区变化过程中,年均温（Bio1）、最湿月降水量（Bio13）和温度季节性变化（Bio4）是影响沙冬青属植物分布的关键因子,并为我国西北干旱半干旱地区具有重要的经济价值并将持续其生态服务功能。     

Effects of elevated nutrients and CO2 emission scenarios on three coral reef macroalgae

Coral reef macroalgae are expected to thrive in the future under conditions that are deleterious to the health of reef-building corals. Here we examined how macroalgae would be affected by exposure to future CO₂ emission scenarios (pCO₂ and temperature), enriched nutrients and combinations of both. The species tested, Laurencia intricata (Rhodophyta), Turbinaria ornata and Chnoospora implexa (both Phaeophyceae), have active carbon-concentrating mechanisms but responded differently to the treatments. L. intricata showed high mortality under nutrient enriched RCP4.5 (“reduced” CO₂ emission) and RCP8.5 (“business-as-usual” CO₂ emission) and grew best under pre-industrial (PI) conditions, where it could take up carbon using external carbonic anhydrase combined, potentially, with proton extrusion. T. ornata’s growth rate showed a trend for reduction under RCP8.5 but was unaffected by nutrient enrichment. In C. implexa, highest growth was observed under PI conditions, but highest net photosynthesis occurred under RCP8.5, suggesting that under RCP8.5, carbon is stored and respired at greater rates while it is directed to growth under PI conditions. None of the species showed growth enhancement under future scenarios, nutrient enrichment or combinations of both. This leads to the conclusion that under such conditions these species are unlikely to pose an increasing threat to coral reefs.