Global warming can seriously influence on the interaction between pest and natural enemy in the agroecosystem due to the differences in optimal temperature ranges. Two aphid-ladybug systems, Myzus persicae-Coccinella septempunctata (M-C) and Aphis gossypii-Coccinella septempunctata (A-C) in the pepper crop were simulated, respectively under four different temperature scenarios including crop development over 244 days with the assumption that the average temperature is higher by 1, 3, and 5 °C than that in Seoul in 2000. Temperature-dependent functions for each aphid-ladybug system were embedded in Rosenzweig-Macathur predator-prey model to explore their population dynamics, and then Dynamic Index was used to quantify the strengths of species interactions. The result shows that the predator-prey population cycles as well as species interactions are getting shorter and stronger in both systems as temperature increased. Especially, the excessively high temperature scenario in Aphis gossypii-Coccinella septempunctata system could result in the extreme species interaction. Therefore, the increasing temperature can facilitate the effectiveness of biological control because of growing crop plant development and much stronger species interaction, although there are increases of the frequency of pest occurrences.

기후변화에 따른 해충개체군 증감모형은 해충방제를 위 한 초발생예찰과 연속적 해충변동 양상의 파악에 매우 중 요하다. 이러한 예측은 농약사용의 효율성을 높이고, 환경 에 적은 영향을 줄 수 있으므로, 현대 해충방제전략의 화두 로 볼 수 있다. 본 연구는 온도변화에 따른 해충의 농약효과 에 따른 사충률의 변화를 개체군 모형과 결합시켜 모의했다. 감수성 점박이응애를 강낭콩을 기주로 20, 25, 30, 35℃에서 Acrinathrin-Spiromesifen 혼합제와 Azocyclotin 유기주석계 농약에 노출시켰다. 생물검정 결과 점박이응애의 사충률은 온도와 농약의 종류에 따라 유의한 차이가 발생했다. 점박이 응애의 개체군 밀도변동 모의는 DYMEX를 이용했으며, 모 의결과 농약의 종류별로 기후변화에 따른 초기방제 시기와 방제횟수에 차이가 나타날 것으로 예측됐다. 본 연구결과는 미래의 기후변화에 대응한 해충방제 전략과 농약 선발에 있 어 중요한 시사점을 제공할 것으로 사료된다.

Araneae species are predators in natural ecosystem interact with various prey species. These linkage can be affected under climate change because species react not just individually but systematically. We focused on potential impact of climate change in Araneae fauna in national scale. In this study, potential species richness of Araneae in South Korea was predicted with MaxEnt (Maximum Entropy) model. Korea Forest Research Institute conducted national scale research of wandering arthropods. They monitored in uniformly set 366 points, and the data contain exact GPS points of study sites. Occurrence data were extracted from Prediction of Distribution and Abundance of Forest Spiders According to Climate Scenario (Korea Forest Research Institute, 2013). With the report, dominant 21 Araneae species that appeared more than 10% study sites were selected to estimate species richness. Training climate data were prepared from observation source of Korea Meteorological Administration. RCP 8.5 scenario data which represent future (2050, 2070) climate condition were downloaded from WORLDCLIM web site. In MaxEnt simulation, occurrence data for 21 species and 19 bioclimatic variables were used. Because the model outputs are expressed in index, the minimum training presence threshold rule was applied to distinguish presence/absence of each 21 species distribution model. We overlaid whole 21 thresholded output to get species richness map. The fluctuation between current and future species richness was calculated to observe changing trend in national scale. The results of Araneae fauna tends to move higher altitude and latitude. Species richness of lowlands is predicted to be diminished, but higher mountains are expected to be more suitable for many spider species. In some South Western coastal areas showed reduced richness in 2050 but will recover in 2070.

Behavioral response is commonly affected by heavy metal toxicity, and behavioral reaction can be measured as sensitive endpoint for sublethal toxicity test and obtained easily and quickly. Also behavioral endpoints may serve as an insightful evaluation tool of the ecological effects of toxic chemicals. In this study, Heterocypris incongruens (Crustacea: Ostracoda) was selected, which is usually used as an indicater species for water quality. H. incongruens was exposed to copper and arsenic for 5 minute and total distance, velocity, turn angle, and angle velocity were measured for 30 minute using video analysis system in laboratory condition. Each endpoints reflected the effects of copper and Arsenic toxicity appropriately. These endpoint have possibility that can be used to identify characteristic behavioral responses to metal toxicity.

Thc climate change has the potential to significantly modify the actual distribution of insect pest with unknown consequences on agricultural systems and management strategies. In this study, Thrips palmi Karny was selected to predict distribution under climate change. T. palmi was introduced and first recorded in 1993 in Korea, and has become a serious pest of vegetable and ornamental crops. The MaxEnt was applied to T. palmi to predict its potential geographic distribution in Korea and Japan under the RCP 8.5 climate changing scenario. The MaxEnt software package is one of the most popular tools for species distribution and environmental niche modeling. The habitat prediction model of T. palmi in Korea was validated by the distribution of T. palmi in Japan. Based on the MaxEnt modeling, T. palmi would expand their potential distribution to whole Korean peninsula except the alpine region in Gangwon-do and Yanggang-do and Hamgyeongbuk-do in 2070s. Therefore, the monitoring system and management strategy for T. palmi should be reconsidered and re-evaluated.

Understanding how species will respond to projected future climate change has become important. However, the impacts of climate change on the ecosystem are very complex and uncertain, we need a reliable tool for approaching it. Mechanistic modeling can be one of the solution for handling the various factors and responses of test organisms in regard to climate change. We introduce the case study on the copper toxicity on D. magna and show the applicability of these mechanistic model approaches. The overall objective of this case study was to simulate the chronic toxicity of copper on Daphnia magna using dynamic energy budget theory with the improved toxicity module component. The toxicity module includes toxic effects on allocation of reserve, structure, and maturity energy in the D. magna. Model calibration and verification were performed using data sets obtained from a laboratory experiment that include growth, maturity and survival measurement data of D. magna during copper exposure. The simulation results show that the response of D. magna under copper exposure was well estimated by toxicity module. Overall, the results show the dynamics model based on DEB theory can be used for estimating long-term metal toxicity on D. magna. Thus, mechanistic modeling can be utilized as a approach tool for evaluating the impacts of climate change on the ecosystem with more mechanistic description.

Climate change is a global phenomenon and has major impacts on ecotoxicology. A variety of environmental variables affected by climate change can alter the fate of chemical and responses of organism. Especially, soil temperature is an important factor in ecotoxicology. Increasing temperature results in an increase in the rate of uptake and degradation of toxic compound. Therefore, the research of temperature effect on toxicity is needed to understand the change of toxic effect under climate change. In this regards, the response of Paronychiurus kimi (Collembola) to Geunsami™ (glyphosate-based herbicide) were evaluated at different temperatures (20℃, 25℃) and soil aging time (7, 15 days). Survived adults and hatched juveniles were counted after 28-day exposures in artificial soil spiked with 1, 5, 50, 100, 500 mg/kg of glyphosate in different temperature and soil aging time conditions. In addition, we investigated the fatty acid composition of Paronychiurus kimi. Increasing soil aging time and temperature, EC20 value of P. kimi was increased. Fatty acid composition of P. kimi was similar with that of Folsomia candida mainly composed of 18:1 w9c, 16:0 and 18:0 fatty acids. UI (Unsaturation Index) and the ratio C16/18 of fatty acid composition decreased with increasing temperature. The 18:0 (Stearic acid) fatty acid increased with increasing concentration of glyphosate.

Behavioral reaction can be measured as a sensitive endpoint for sublethal toxicity of copper, and can be used to obtain easily and quickly. Also behavioral endpoints may serve as a more insightful evaluation tool of the ecological effects of toxic chemicals. In this study, four invertebrates in freshwater which are usually used indicate species for water quality were selected as test species (Chironomus riparius, Heterocypris incongruens, Daphnia magna, and, Triops longicaudatus). Each test species was exposed to copper for 6 hours, and total distance, velocity, and, turn angle were measured for 1 hour using video analysis system (Ethovision : Noldus Information Technology) in laboratory condition. Each endpoints reflected effect of copper toxicity appropriately for all test species. These endpoint have possibility that can be used to identify characteristic behavioral responses to a metal toxicity. We viewed this study as a preliminary experiment for future research to investigate the significance of behavioral endpoints to various toxic chemicals.

Insects reflect climate change dramatically because insects are poikilotherm and have huge biodiversity. Also, the prediction of insect distribution is very significant due to the position of this group giving diverse ecological services including their extraordinary economic importance. Accurate modeling of geographic distributions of insect species is crucial to various applications in ecology and conservation. The best performing techniques often require some parameter tuning, which may be prohibitively time-consuming to do separately for each species, or unreliable for small or biased data sets. The purpose of this study is to introduce and compare several models to predict insect distribution under climate change in Korea. This work would be helpful to researchers or decision makers by giving practical advice, for example, kinds of input/output data, applicability to GIS, to select appropriate model to predict insect distribution.

Environmental risk assessment aims to estimate the impacts of various stressors on populations and communities in the environment. However, most of the exposure tests conducted under the laboratory level. This gap between the controlled condition of the experiments and the complexity of the field situation can lead to irrelevant estimation of stress effects. For this reason, dynamic model approach in ecology that including integrated mechanistic understanding has become important. The dynamic models at the individual level can be used to interpret the individual’s response to stress, extrapolate which response to untested conditions, and predict the impacts on the higher ecological level. The overall objective of this case study was to simulate the chronic toxicity of copper on Daphnia magna using dynamic energy budget theory with the improved toxicity module component. The model system was constructed and evaluated, using the PowersimⓇ software. The toxicity model system was integrated with toxic effects on allocation of reserve, structure, and maturity energy of D. magna into improved toxicity module. The model was calibrated and verified by actual data sets where obtained from a laboratory experiment including growth, maturity and survival measurement of D. magna during copper exposure. The simulation results showed that the response of D. magna under copper exposure was well estimated by model system.

Recently, an integrated approach in insect ecology that including development of biological models and estimation of various effects using a logical model has become important. Through the biological components of ecosystem having complex temporal and spatial patterns, and complicated interactions of biotic and abiotic factors, dynamic models can be useful tools to investigate the whole ecosystems. Pollutants in terrestrial ecosystem can be transferred to insect body through insect’s sucking plant tissue, and effect on their biological properties. Trend of pollutants transfer from soil to plant root can be estimated using free ion activity model (FIAM), and distribution and accumulation in plant parts can be described by dynamic model with water potential, water translocation, and transfer rate. Biological response of plant and insect can be illustrated the dynamics model based on experiment data. The combination of these models show an overall behavior of toxicant and the interaction between plant and insect with time. The objectives of the research are to comprehensively analyze the transfer and effects of pollutant in soil, plant and insect system and to develop the assessment technique for soil ecosystem using dynamic modelling concerning the causal relationship and feedback processes. We are aimed specifically at prediction and assessment of various polluting scenarios of soil ecosystem through data collection from laboratory and field investigation, modelling and evaluation using module software programing.

The use of aquatic species in ecotoxicity research is well established in developed countries. However there are limitations of using the species that are not native to Korea, and the toxicity data produced by domestic test species are significantly needed to reflect the domestic situation. In this study, the applicability of 3 kinds of native species, Chironomus yoshimatsui Martin et Sublette, Ephemera orientalis McLachlan and Heterocypris incongruens Ramdohr, as aquatic toxicity test species was studied. Also, the integration method of each species response to various industrial effluent and surface water was developed. In ecotoxicological researches using macro invertebrates, temperature is one of the most important toxicity-modifying factors, and temperature effect is species specific. Besides temperature effect, there are other physico-chemical factors that can affect test organisms, such as pH, water hardness and dissolved organic matter. The ideal test species for freshwater quality assessment is very sensitive to various pollutant but resistant to wide ranges of physico-chemical properties of environmental media. Behaviour is the cumulative interaction of a variety of biotic and abiotic factors that represents the animal′s response to internal and external factors and relates one organism to another. So, it is a major mechanism by which animals adapt to changes in their environment, including exposure to contaminants. Despite the importance of behavioral ecotoxicological test, there are few researches to assess the quality of freshwater and its sediment, in part due to the difficulties to obtain detailed quantitative data. This study shows the potentiality of behavioral test for water quality assessment using burrowing behavior of midge species exposed to several heavy metals. Finally, we propose a method which integrates each test into one concise and useful index and can be applied to various field water.

A new collembolan species (Paranura rosea) which was native to Korea was selected for evaluating the effect of temperature on their biology. Development, and reproduction of P. rosea were investigated at 15, 20, 25 and 30℃ Hatchability of egg was not affected by experimental temperature, and the lower threshold temperature for development of P. rosea was estimated to be 7.53℃. The temperature reduced the juvenile and adult (maturity period). The intrinsic rate of natural increase and finite rate of increase per week at 20℃ which are maximum values showed significant difference with other experimental temperatures. Survival rate, cumulative reproduction and head capsule width was fitted by several models. Especially, the model which fitted for estimating head capsule width was used to determine their life stage. Estimated head capsule width of P. rosea at the initial oviposition varied with temperature from 0.36 ± 0.007 to 0.45 ± 0.007 with maximum at 20℃ and minimum at 30℃, and significant difference was observed at all the experimental temperature (P<0.05). However, estimated head capsule width at the last oviposition showed different statistically result at only 30℃. Molting frequency per week of one P. rosea was increased as the temperature increased. Based on this study, temperature greatly influenced on their life stage and reproduction. Therefore, relationship between temperature and P. rosea is very important for understanding their biology.

We evaluated the effect of water pH (6, 7, 8 and 9) and hardness (40mg/L and 160mg/L as CaCO3) on the growth of H. incongruens. Both water pH and hardness affected the growth parameter of H. incongruens such as head capsule width and maturity time. The head capsule width of the adults in the highest ph condition was 9.7% increased compared to the lowest ph condition. The maximum difference of the maturity time was 192 hours among the test conditions. Overall, as water ph level increase makes head capsule size of the test animal large, the inter-molt period and maturity time become shorter significantly. The effect of water hardness increasing showed a similar tendency with ph level. Especially, the difference of the growth parameter among the test conditions was increased by growing test animal. There are strong correlation between available amount of intake calcium and growth parameters of test animal. These results indicate that because of calcium demand for growth, water pH level and hardness are the important effect factor in life-cycle of the H. incongruens..

Proteomics may help to detect subtle pollution-related changes, such as responses to mixture pollution at low concentrations, where clear signs of toxicity are absent. Also proteomics provide potential in the discovery of new sensitive biomarkers for environmental pollution. We utilized SELDI-TOF MS (surface enhanced laser desorption. / ionization time-of-flight mass spectrometry) to analyze the proteomic profile of Heterocypris incongruens exposed to several heavy metals (lead, mercury, copper, cadmium and chromium) and pesticides (emamectin benzoate, endosulfan, cypermethrin, mancozeb and paraquat dichloride). Several highly significant biomarkers were selected to make a model of classification analysis. data sets obtained from H. incongruens exposed to pollutants were investigated for differential protein expression by SELDI-TOF MS and decision tree classification. Decision tree model was developed with training set, and then validated with test set from profiling data of H. incongruens. Machine learning techniques provide a promising approach to process the information from mass spectrometry data. Even thought the identification of protein would be ideal, class discrimination does not need it. In the future, this decision tree model would be validated with various levels of pollutants to apply field samples.

This study was conducted to examine the potential of surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) to screen Tetranychus urticae resistance to pyridaben and dicofol. T. urticae is one of the most important pests in greenhouse and orchard, and huge expense is needed to control because of its strong resistance to acaricides. Consequently speedy and accurate monitoring of acaricidal resistance is the key factor of IPM for T. urticae. SELDI-TOF MS is a novel approach to biomarker discovery that combines two powerful techniques: chromatography and mass spectrometry. It can provide a rapid protein expression profile of acaricidal sensitive and resistant T. urticae. In this study we had different protein and peptide patterns between sensitive and resistant strains to pyridaben and dicofol. In the future this results could be a useful data to develop a good monitoring tool of site and host specific mite resistance to various acaricides.

Soil contamination can be one path for stream and groundwater contamination. In this study, the toxicity of soils sampled in the vicinity of the abandoned mine located in the Gyeonggi province was evaluated using freshwater organisms Heterocypris incongruens. Two different exposure scenarios, one is in the aqueous only exposure, and the other is in the aqueous + soil exposure. The seven different soil samples were tested depending on the contamination level; reference (1 soil), moderately contaminated (4 soils) and highly contaminated (2 soils). In the toxicity tests, H. incongruens were exposed to water extracts (aqueous only exposure) and soils (aqueous + soil exposure) which were serially two-fold diluted with either EPA moderate hardwater or clean sand, respectively. After 6 days of exposure, no significant impact on the survival was found in the both systems for reference soil, while only significant impact was found in the aqueous + soil system for moderately contaminated soil. And the survival of H. incongruens was dramatically decreased with decreasing dilution series for highly contaminated soils. Interestingly, the toxicity of aqueous + soil system was higher than that of aqueous only system, implying the exposure of chemicals to H. incongruens may be a consequence of its foraging behavior onto the surface of sediment. From the results of this study, the freshwater organism H. incongruens can be used as surrogate test species to assess the soil contamination.

Sedimentation of soil particles in water is perhaps the most significant pathway to contamination of aquatic ecosystems. In this scenario, the use of freshwater organisms for assessing sediment toxicity will be considered more ecologically relevant than tests that use aqueous soil extracts. To evaluate the toxicity of soils sampled in the vicinity of the abandoned mine located in the Gyeonggi province, Daphnia magna were exposed to a 1:4 of soil to water which soil samples were serially two-fold serially diluted with clean sand to concentrations ranging from 6.25 to 100 % % (w/w) for 24- and 48-h. Irrespective of exposure time, the survival of D. magna for reference soil was not decreased, while the survival of D. magna showed high sensitivity to the soils with moderate as well as high metal concentrations. Moreover, the heavy metal concentrations in the water samples increased with increasing the heavy metal concentrations in the soils, which indicates the increased sensitivity is the consequences of the bioavailable fraction of contaminants in soils. These results clearly showed that the freshwater organism D. magna can be used as test species to assess the potential impact of soil contaminants into aquatic ecosystems.

Biological control of greenhouse whitefly, Trialeurodes vaporariorum in greenhouse tomatoes with the parasitoid Encarsia formosa has been evaluated in Korea. However implementation of biological control program is retarded due to the reasons that lacks of site specific strategies. Aims of the present research are: (1) To develop an effective biological control method of the whitefly in tomato plants; the following were studied: (a) development of proper introduction rate of parasitoid, E. formosa, for the control of whiteflies, and (b) development of the effective control method of American serpentine leafminers with a parasitoid, Diglyphus isaea. (2) To build a computer-simulation model in which all factors are incorporated which have been studied in the relationship between whitefly and the parasitoid. The computer-simulation models would be used to estimate the effect of future developments in the greenhouse industry on the biological control of the greenhouse whitefly using E. formosa. More general goals are to develop reliable evaluation techniques to test the pest-control ability of natural enemies prior to their use in practical situations and to determine which role simulation models may play in estimating the results of biological control in new situations.

Male cicadas produced species-specific calling songs to attract conspecific receptive females. Male cicadas typically occupy tree trunks or tree branches during calling song production. We studied calling site preference in four species of cicada: Cryptotympana dubia, Meimuna opalifera, Oncotympana fuscata, and Meimuna mongolica. Several males were observed to sing together in a tree in C. dubia, but males of other species tended to sing singly in trees. There were also cases in which two or three individuals of different species sang together in a tree. Species differed significantly in height of and distance to trunk from calling site. Both tree height and tree crown were significant factors for calling site preference. The height of calling site was the highest in C. dubia, followed by M. opalifera, M. mongolica, and O. fuscata. The distance to trunk from calling site in M. opalifera was the farthest and was significantly different from those of other species. Males of other species tended to sing close to tree trunks. Males of M. opalifera were mobile when they produced calling songs, whereas males of other species were stationary. That is, males of M. opalifera sang only for short periods of time and moved around adjacent trees. Segregation of calling sites suggests that these four cicada species occupy different sections of trees, thereby avoiding competition for calling sites.