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Ensemble species distribution modeling offers a robust approach to reduce the inherent uncertainties associated with single models, and ultimately providing more accurate predictions of regions with a heightened probability of occurrence. As Corythucha ciliata (Say) damages deciduous trees in diverse environments, including urban, suburban and forested regions, the objective of this study was to predict the potential distribution of C. ciliata by developing an ensemble model that comprehensively considered the biological and habitat traits of the pest using the CLIMEX and MaxEnt models. Although the ensemble model did not have significantly improved performance, compared with the single MaxEnt model, it was robust compared with distribution data. Our predictions suggest that C. ciliata will gradually expand its range from its current distribution in response to climate change, necessitating focused monitoring and pest‐control efforts in the predicted regions. This study not only evaluates pest distribution but also provides crucial insights into effective control strategies, which are adaptable to other pest management scenarios. [ABSTRACT FROM AUTHOR]

The western conifer seed bug (WCSB) Leptoglossus occidentalis (Heidemann) (Heteroptera: Coreidae) is a pest insect that causes significant losses of coniferous trees worldwide. In this study, we sought to project the potential distribution of the WCSB based on dual CLIMEX modeling and random forest (RF) analysis to obtain basic data for WCSB monitoring strategies. The CLIMEX model, a semimechanistic niche model that responds to climate‐based environmental parameters, is a species distribution model that focuses on regional climatic suitability. Given that this model can be used to select areas that are likely to reflect the climatically favorable spread of species, which we initially used CLIMEX to evaluate the potential distribution of the WCSB. The RF algorithm was used to predict the potential occurrence of WCSB and to evaluate the relative importance of environmental variables for WCSB occurrence. Using the RF model, land cover was found to be the most important variable for classifying the presence/pseudo‐absence of the WCSB, with an accuracy of 77.1%. Climatic suitability for the WCSB was predicted to be 2.4‐fold higher in Southern Europe than in Western Europe, and the WCSB was predicted to occur primarily near coniferous forests. Given that CLIMEX and RF analyses yielded different prediction results, using the findings of both models may compensate for the shortcomings of these models when used independently. Consequently, to ensure greater prediction reliability, we believe that it would be beneficial to base predictions on the combined potential distribution data obtained using both modeling approaches. [ABSTRACT FROM AUTHOR]

The Argentine ant (Linepithema humile) is an invasive species that rapidly enters into new areas, causing worldwide ecological concern. Early assessment of its potential habitat could indicate areas that we need to pay attention to in advance, to prevent its invasion; therefore, in this study we aimed to predict the potential spatial distribution of the Argentine ant and analyze the climatic characteristics of its occurrence sites. The CLIMEX model was used to predict the spatial distribution of this ant species, while the probability density function was employed to extract climatic preferences in places where their main habitats are located. High climatic suitability was predicted in the eastern United States, eastern South America, central Africa, eastern Australia, and a few regions in India and China, suggesting the high possibility of its invasion worldwide. The frequency of occurrence was highest at approximately 20°C monthly average maximum temperature, 8°C monthly average minimum temperature, and 10 mm monthly precipitation. In addition, the occurrence records of Argentine ants were mostly shown to be above sub‐zero temperatures. We expect that these results can be used to identify new areas exposed to the risk of Argentine ant invasion and for further application to establish monitoring strategies in advance. [ABSTRACT FROM AUTHOR]

Dasineura oxycoccana, the blueberry gall midge, has damaged domestic blueberry cultivation since its presence was confirmed in Korea. In this study, the domestic climatic suitability of D. oxycoccana was evaluated using the CLIMEX model, which comprehensively integrates the species biology and regional climate. In addition, we derived the risk posed to major areas of blueberry cultivation by considering the domestic potential distribution of D. oxycoccana based on climatic suitability D. oxycoccana showed the highest occurrence suitability on the southern coast under the current climate, and its population is expected to gradually increase inland due to climate change. Jeju and the southern coast were the major areas that were presently found to be at risk from D. oxycoccana; the area at risk from D. oxycoccana is expected to extend to southern Gyeonggi‐do and Ganwon‐do by 2040 and 2060, respectively. D. oxycoccana was predicted to occur throughout the country according to climate change, suggesting increase in its infestation in blueberry cultivation. Therefore, we expected this study provides precautionary evaluation for monitoring and controlling the pest. [ABSTRACT FROM AUTHOR]

Spatial ensemble modeling by overlaying host distribution and climatic suitability predicted by the developed CLIMEX model to evaluate the potential distribution of Leptoglossus occidentalis in South Korea. [Display omitted] • We develop the CLIMEX model suitable for L. occidentalis distribution. • The model could predict 99% of actual distribution in North America. • The developed model was applied to predict L. occidentalis in South Korea. • Ensemble map combining climatic suitability and coniferous forests was constructed. • L. occidentalis distribution would decrease by climate change in South Korea. Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae) is a notorious pest that causes irreversible damage to coniferous forests in South Korea. However, an effective control strategy is still under development. In this study, we used CLIMEX to analyze the potential distribution of L. occidentalis in relation to climate and host plants in South Korea for the identification of effective control spots. The climate needs of L. occidentalis under current and future climate conditions were analyzed and projected on a map along with the distribution of coniferous forests. The CLIMEX model projected that the area of L. occidentalis distribution would decrease slightly in 2060 compared with that at present. However, it was projected that occurrence in mountainous regions would be sustained, suggesting continued damage to coniferous forests in South Korea. [ABSTRACT FROM AUTHOR]

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) is a forest pest that damages a wide range of trees in areas where it has recently been introduced, demanding a proactive evaluation of its possible future distribution.This study aimed to project the potential distribution of A. glabripennis using species distribution modelling and constructed an ensemble map for evaluating global risk areas.We used CLIMEX and MaxEnt to evaluate the potential distribution of A. glabripennis as a function of current and future climates.The results showed that the models predicted a high probability of A. glabripennis distribution where this species is currently found, and the suitable climate was shifted northward due to climate change.The projected area differed between the models because of different modelling algorithm and climate change scenario; thus, an ensemble map projecting the consensus areas from two models was constructed to identify the risk areas that corresponded to the eastern United States, Europe, and native countries, Korea and China, and nearby Japan.From the perspective of ensemble modelling for evaluating species distributions with reduced uncertainties, this study will enhance the model reliability for defining areas at risk of A. glabripennis occurrence. [ABSTRACT FROM AUTHOR]

Predicting the potential distribution of longhorn crazy ants using CLIMEX and Maxent and ensemble mapping consensus areas using two models to evaluate the invasion risk in South Korea. [Display omitted] • CLIMEX and Maxent were used to evaluate potential longhorn crazy ant distributions. • Temperature-related variables mainly affect the distribution of longhorn crazy ants. • The consensus regions of two models were predicted in response to climate change. • An ensemble map projecting the consensus regions in South Korea was constructed. • Based on this, the invasion risk is high in coastal areas and the southern inland. The longhorn crazy ant (Paratrechina longicornis) is a globally distributed ant species with a high invasion risk, suggesting the need to use species distribution modeling to evaluate its potential distribution. Therefore, this study aimed to predict the potential distribution of longhorn crazy ants in response to climate change by using CLIMEX and Maxent and identifying the climatic factors that influence their habitat. Then, the model outcomes were used to construct an ensemble map to evaluate invasion risk in South Korea. The results indicated that temperature-related variables mainly affect the distribution of the longhorn crazy ant, and the two models showed consensus regions in South America, Africa, Australia, and Southeast Asia. Due to climate change, it was expected that the northern limit would somewhat rise. In South Korea, high-risk areas were predicted to be located along the coasts, but they would expand as a consequence of climate change. Since the invasion of longhorn crazy ants has occurred via commercial trades, a relatively high risk in coastal areas demands a high level of attention. We expect that this study will provide initial insight into selecting areas for longhorn crazy ant quarantine with ensemble species distribution modeling. [ABSTRACT FROM AUTHOR]

Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), known as common cutworm, is a worldwide pest that causes severe damage to various crops and vegetables in South Korea. In this study, we predicted the potential distribution of S. litura in South Korea in a climate change scenario by applying species distribution modeling. We used the CLIMEX software as a main tool and determined optimal parameter values to simulate the current distribution of S. litura in Asia. We then used these parameter values to predict the species' future distribution in South Korea. As a result, we prepared maps indicating areas with suitable climate for S. litura and showed that these areas gradually increased as a result of climate change. Approximately 98% of the areas in South Korea were predicted to have a favorable climate for S. litura in 2100; 63.2% of the area in South Korea is currently favorable. To the best of our knowledge, this is the first study to predict the potential distribution of S. litura in South Korea, and it provides the basic data necessary to establish an optimal control strategy of this species. [ABSTRACT FROM AUTHOR]

Abstract: Globalization has changed the habitats of various species, resulting in harmful pest invasion. Among these pests, Metcalfa pruinosa has caused worldwide economic and hygienic damage in both urban and agricultural/forested areas. It has been reported that prediction of pest distribution is key to the management of pest prevention. Hence, this study aimed to predict the potential geographic distribution of M. pruinosa under the current climate and under a climate change scenario. CLIMEX, modeling software that analyzes the habitat suitability of a target species based on comprehensive climatic and physiological data, was used mainly to establish a map of predictive distribution of M. pruinosa at present and in the future. Based on our simulations, we predict that M. pruinosa will tend to extend its distribution northward in North America and Europe. We conclude that climate change could result in M. pruinosa invasion in a northward direction, suggesting the need for a thorough system of control and prevention. [ABSTRACT FROM AUTHOR]

• CLIMEX is a mechanistic SDM tool, but its performance was hard to be measured. • True skill statistics was applied for quantitatively evaluating CLIMEX performance. • CLIMEX performance was evaluated according to regional scale and species records. • True skill statistics was compared with another metric to apply it the CLIMEX. • True skill statistics was differed with the scale, records and classification threshold. The species distribution model (SDM) predicts the potential distribution of a species as a function of abiotic variables. CLIMEX is a SDM that mechanistically evaluates the climatic suitability of a species in a specific area. However, compared with other SDMs, the metrics for quantitatively evaluating CLIMEX performance are limited. Hence, this study quantitatively evaluated the performance of the CLIMEX models of six example species by applying the metrics used for machine-learning-based SDMs. The results showed that the performance of CLIMEX had a minimum true skill statistic (TSS) of 0.35 and a maximum of 0.78 depending on the species. Depending on the scale of the prediction area, number of occurrence coordinates, and classification threshold, CLIMEX performance can be evaluated by applying true skill statistics (TSS). Although this method is not perfect because of the characteristics of CLIMEX modeling, we expect it to be a useful option before conceiving the best method to evaluate mechanistic SDM. [ABSTRACT FROM AUTHOR]

• PWD occurrence possibility was evaluated by MaxEnt based on five-year records. • Climatic suitability of insect vectors was predicted by using CLIMEX model. • Potential risk of PWD was evaluated with an ensemble of PWD and insect vectors. • PWD was predicted to occur in low-altitude areas around the existing records. • PWD was expected to be disperse by insect vectors throughout the country. Pine wilt disease (PWD), caused by Bursaphelenchus xylophilus , a pine wilt nematode (PWN), is one of the most serious forest diseases of the genus Pinus and a nationwide concern in South Korea. It is spread by vectors of the sawyer beetles, genus of long-horned beetles, and it rapidly kills the host plant, resulting in economic and ecological losses. Therefore, developing an early monitoring system using spatial evaluation to minimize PWD dispersion is necessary. In this study, we predicted the distribution of PWD and of its insect vectors using a spatial ensemble model with MaxEnt and CLIMEX. High-risk areas were mostly concentrated around low-altitude and current occurrence areas. The risk of PWD under future climatic change scenarios is significantly reduced. However, PWD is expected to be distributed in most of South Korea by insect vectors, suggesting a continuous damage from PWD without an appropriate control strategy of its insect vectors. This study provides fundamental data for efficiently establishing a monitoring strategy under limited resources by proposing areas to focus in advance. [ABSTRACT FROM AUTHOR]

The significant dependence of agricultural productivity on pest control requires pest distribution predictions at an early stage of pest invasion. Because pest cycles are critically affected by climate, climate is one of the most important factors for predicting an invasive pest. CLIMEX is a highly effective tool that can predict potential geographical species distributions, and test the regional suitability for a target species' habitat based on data including climate change scenarios. CLIMEX has been recently used in Europe, North America, China and Australia, among others. However, for modeling species distributions in Korea, the use of the model has been limited to date. This study aimed to first introduce the function and application of CLIMEX by reviewing important studies using this model. Second, we investigated previous studies using the model simulation to demonstrate the practical applicability of CLIMEX for the agricultural sector, and its use in forecasting. [ABSTRACT FROM AUTHOR]

Soil temperature is an important factor for determining ant species inhabitation, but it has rarely been applied in species distribution modeling due to limited data sources. Hence, this study aimed to develop a predictive model for soil temperature and evaluate the potential distribution of a few ant species in South Korea. The monthly maximum and minimum soil temperatures were predicted by linear regression as a function of the monthly maximum and minimum air temperatures. Then, the developed model was used to predict the potential distribution of the tropical fire ant (Solenopsis geminata Fabricius; TFA), red imported fire ant (Solenopsis invicta Buren; RIFA), and yellow crazy ant (Anoplolepis gracilipes Smith; YCA). Three ant species were selected because they have globally exerted negative impacts on the ecology of the invading area. The developed model could predict soil temperatures at 5, 10, 20, and 30 cm deep with an R 2 value of 0.95. The climate suitability of TFA, RIFA, and YCA, predicted by soil temperature in the CLIMEX model, was found to be up to 25, 12, and 65 times higher than the climate suitability predicted by air temperature, respectively. This study showed that the potential distribution predicted based on air and soil temperature could be different for a species inhabiting the ground, suggesting that it is necessary to consider not only the outside environment, but also the soil environment, for an accurate prediction. • This study developed a predictive model for soil temperature in South Korea. • Regional soil temperature was predicted as a function of air temperature. • Soil temperature DB was constructed for species distribution modeling. • Suitability of ants were evaluated under soil and air temperatures in South Korea. • Suitability in the soil was higher than that under air temperature for ants. [ABSTRACT FROM AUTHOR]

Potato tuber moth (Phthorimaea operculella), one of the leading potato-damaging pests in the world, has caused severe damage to potato production in South Korea after its introduction in the 1960s. This study surveyed the field occurrence of potato tuber moth in various sites in South Korea and used the results to validate the CLIMEX model, which spatiotemporally evaluated the potential distribution of potato tuber moths in response to climate change. The potato tuber moths were predicted to appear throughout the country, consistent with the results obtained for potato tuber moths in 96% of the field survey area. In addition, the climatic suitability of potato tuber moths will remain high due to climate change, suggesting a high risk for damage to seasonal potato production from seeding to harvesting. This spatiotemporal assessment of potato tuber moth distribution is expected to aid in establishing control strategies optimized based on time and place. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the potential distribution of red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), in response to climate change in South Korea using CLIMEX, a species distribution model. We further attempted to evaluate the risk of the distribution/invasion and subsequent dispersion by considering climatic suitability, and functional characteristics of cities and covered cultivated areas. The climatic suitability has extended from the southern and coastal regions to inland regions due to climate change. The number of areas with EI (Ecoclimatic Index) values of more than 20 was 9 (12%) in the current climate; the value was assumed to increase to 23% (2040), 24% (2060), 42% (2080), and 62% (2100) from the South Korea coast to inland. We predicted that May to October would be the most active period in seven domestic high-habitation areas. We also analyzed the invasive risk of the red imported fire ant into covered domestic cultivation areas. Considering climatic suitability, we determined that Jeju, Pohang, Busan, Ulsan, Mokpo, and Gosan would be the most affected areas. This study can provide baseline data for the management of invasive species nationally and for regional control through predictions of the probability of settlement and direction of spread. [ABSTRACT FROM AUTHOR]

This study evaluated the potential distribution of the potato tuber moth. This species severely impacts global potato production, especially in China and India, which have the world's largest potato production. We developed two indices considering host plant availability and production in addition to climatic suitability, which was simulated using the CLIMEX model. Thus, three different indices were used to project potential distribution of the potato tuber moth under a climate change scenario: (1) climatic suitability (ecoclimatic index (EI)) (EIM), (2) climatic suitability combined with host plant availability (EIN1), and (3) climatic suitability combined with host plant production (EIN2). Under the current climate, EIM was high in southern India and central to southern China, while EIN1 and EIN2 were approximately 38% and 20% lower than EIM, respectively. Under the Special Report on Emissions Scenario A1B, the potato tuber moth would probably not occur in India, but its distribution could be extended to the north, reaching N47°. The areas with the highest climatic suitability by potato tuber moth based on three indices were Sichuan and Karnataka in response to climate change. These areas require adequate pest control, such as prevention of spread through transport of potato seed or by using cold storage facilities. [ABSTRACT FROM AUTHOR]