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.

Myzus persicae, Heliothis assulta and Frankliniella occidentalis are the most severe pests of pepper in Korea. IPCC (Intergovernmental Panel on Climate Change) reported that the temperature would increase 7℃ at the end of this century. According to the elevated temperature, the pest population will be grow dramatically. We need to predict the pest-population size to maintain good crop productivity. DYMEX and CLIMEX are commercial software developed by CSIRO in Australia, to build and simulate population dynamics models. Using this software, we predicted population dynamics of M. persicae, H. assulta and F. occidentalis applying past climate data (1970) and future climate data (2070) which were generated by National Institute of Meteorological Research (NIMR). The population growth rates of M. persicae, H. assulta and F. occidentalis were 6300, 16 and 950 times, respectively, with 5 degree elevation. Therefore pest management should be conducted intensively in the future.

In Korea very few studies have been conducted in relation to collembola sensitivity to pollutants in populations exposed to soil contaminants in particular heavy metals. The objective of the current research were to study the thermal effects of selected heavy metals on the survival and reproduction of P. rosea in order to assess its applicability as a test species. Petri dishes (87 mm diameter, 15 mm height) were used for compact soil toxicity test and were filled to a depth of 0.5 mm with 6 g artificial soil and 3.5 mL distilled water was added. 20 adults (6 weeks from egg stage) were introduced to each petri dish and placed in two incubators set at 20℃ and 25℃, respectively under continuous darkness. The 28 days EC50s for cadmium in compact soil at 20℃ and 25℃ were 48.9031 and 91.3585 mg/kg, respectively. This thermal toxicity test of P. rosea is advantageous for various environmental sudies, such as toxicity tests.

Myzus persicae, Heliothis assulta and Frankliniella occidentalis are major pepper pests in Korea. The objective of this study was to assess the pepper-yield decrease caused by population change of M. persicae, H. assulta and F. occidentalis. with temperature elevation. It is easy to expect that climate change will increase crop damage caused by pests. Therefore we should predict pest-population dynamics exactly and find the best available strategy for the pest management. Based on the many reported results of temperature development of the three kinds of pest, we simulated the future population dynamics using the computer softwater, DYMEX, developed by CSIRO. The results were that the population sizes and outbreak frequency of 3 kinds pest would increase with global warming. This work may be helpful to establish an effective pest management.

Heliothis assulta is the most severe pest of pepper in Korea. The management of this pest is very difficult because the larva live in the pepper fruit and emerge continuously. There are relatively abundant studies about temperature development of H. assulta, but few works are available to describe its future population dynamics which is caused by global warming. If we predict the long-term-population dynamics we can manage the H. assulta more effectively. Therefore we simulated the population size using the computer softwater, DYMEX, developed by CSIRO in Australia. Especially, we predicted population dynamics of H. assulta applying past climate data (1965-1985) and future climate data (2065-2085) which were generated by National Institute of Meteorological Research (NIMR). Comparing to past population dynamics, the epidemic size and frequency would increase in the future. This means that the population management of H. assulta should be conducted more sophisticatedly.

Two cherry tomato plant cultivars (Lycopersicon esculentum Miller, cultivars ‘Koko’ and ‘Pepe’) were supplied with high (395 ppm), medium (266 ppm) and low (199 ppm) concentrations of nitrogen to determine the influence of nitrogen fertilization on development, cultivar preference and honeydew production by greenhouse whiteflies, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae). The nitrogen, protein, andchlorophyll content of tomato leaves were higher in the high nitrogen supplied plants than in the medium or low nitrogen supplied plants, but the sugar content showed an inverse relationship. The developmental times of eggsand nymphs decreased as the nitrogen concentrations increased in both cultivars. The preference of T. vaporariorum was compared by counting the number of eggs deposited on leaves in choice and non-choice tests. In the non-choice test, no significant nitrogen treatment effects were observedbut the upper plant stratum was preferred for egg laying. In the choice test, there were significant main effects of cultivar and nitrogen concentration. T. vaporariorum laid eggs more on leaves of plants with higher nitrogen at the upper stratum. In both experiments, T, vaporariorum preferred the ‘Koko’ cultivar to the ‘Pepe’ cultivar. The honeydew production of T. vaporariorum nymphs increased with decreasing nitrogen treatment concentrations. The largest honeydew production was detected in the ‘Pepe’ cultivar grown at low nitrogen concentration. It is concluded that cultivar ‘Pepe’ had an advantage over ‘Koko’ in term of T. vaporariorum management program in tomato greenhouses.