Pitfall traps that use ethylene glycol as a preservative solution are commonly used in arthropod research. However, a recent surge in cases involving damage to these traps by roe deer or wild boars owing to the sweet taste of ethylene glycol has prompted the addition of quinone sulfate, a substance with a pungent taste, to deter such wildlife interference. This study aimed to assess the effects of quinone sulfate on arthropods collected from pitfall traps containing ethylene glycol. We strategically positioned 50 traps using ethylene glycol alone and 50 traps containing a small amount of quinone sulfate mixed with ethylene glycol in a grid pattern for systematic sampling at the Gwangneung Forest long-term ecological research (LTER) site. Traps were collected 10 days later. The results revealed a notable effect on ants when quinone sulfate was introduced. Specifically, it decreased the number of ants. In a species-specific analysis of ants, only Nylanderia flavipes showed a significant decline in response to quinone sulfate, whereas other ant species remained unaffected. Additionally, among the arthropod samples obtained in this survey, we identified species or morpho-species of spiders, beetles, and ants and assessed species diversity. Consequently, the utilization of quinone sulfate should be undertaken judiciously, taking into account the specific species composition and environmental characteristics of the monitoring site. Our study also highlighted the significant response of various arthropod groups to variations in leaf litter depth, underscoring the crucial role of the leaf litter layer in providing sustenance and shelter for ground-foraging arthropods. Furthermore, we have compiled comprehensive species lists of both spiders and ants in Gwangneung forest by amalgamating data from this investigation with findings from previous studies.
The distribution pattern of species richness was determined by temperature. To examine the relationship between hemipteran richness and temperature, hemipteran species were collected using pitfall traps at six different oak forest sites with different annual mean temperatures in South Korea. Multiple linear regression analyses were conducted with mean annual temperature (MAT) and plant richness to evaluate differences in hemipteran richness. The influences of MAT and plant richness of study sites on hemipteran richness were examined by comparing three models (plant richness+MAT+MAT2, plant richness+MAT, and MAT) or two models (plant richness+MAT and MAT). Hemipteran richness showed an inverse diversity pattern as a function of temperature, with higher species richness at lower temperature sites. Meanwhile, Aphididae showed a bell-shaped diversity pattern with the highest value at low medium temperatures. The regression analysis showed that hemipteran richness was affected by temperature and plant richness in their habitats.
Using data from flies collected with pitfall traps in 365 forests on a nationwide scale in Korea, the abundance and distribution changes of two families (Phoridae and Lauxaniidae) in Korean forests were predicted at the genus level according to two climate change scenarios: RCP 4.5 and RCP 8.5. The most suitable temperature for the 17 major genera was estimated using a weighted average regression model. Stichillus and Anevrina displayed the lowest optimum temperature with 7.6℃ and 8.5℃ in annual mean temperature, respectively, whereas Chonocephalus had the highest optimum temperature with 12.1℃. Among thirty genera, seven genera (four from Phoridae and three from Lauxaniidae), which showed their abundance in a bell-type or linear pattern along the temperature gradient, were used for predicting the distribution changes according to the future climate change scenarios. All the taxa of this study are expected to decrease in abundance and distribution as a function of temperature increase. Moreover, cold-adapted taxa were found to be more affected than warmadapted taxa.
The effects of forest type and fragmentation of forests by a road on the beetle community were investigated in the Gwangneung Forest, South Korea. Beetles were collected monthly using pitfall traps and by sweeping at 16 sites (eight in coniferous forests and eight in deciduous forests) for one year from April 1993 to April 1994, excluding winter. A total of 17,616 beetles belonging to 271 species from 39 families were collected. Among them, Synuchus cycloderus was the dominant species, with 14,060 individuals accounting for 80% of the total population. The influence of forest type (coniferous and deciduous) or sampling region (fragmented by a road) on species richness (number of species) was observed. We found that species richness was substantially different depending on the sampling method and taxa used. Beetles collected using pitfall traps responded more sensitively to habitat types than those collected by sweeping. Four dominant families differently responded to forest fragmentation and forest types. Carabidae was influenced by forest fragmentation, whereas Staphylinidae and Curculionidae were influenced by forest types. Chrysomelidae was not influenced.
산불 후에 일어나는 개미군집의 변화양상을 파악하기 위해 산불이 난 산림에서 자연적으로 식생복원이 이루어진 곳, 인위적으로 조림한 곳, 산불이 나지 않은 곳의 3개 조사지에서 2005년부터 8년간 함정트랩으로 개미를 조사하였다. 모두 24종이 채집되었고 스미스개미(Nylanderia flavipes)가 가장 풍부하였다. 산림을 선호하는 개미종(예, 일본장다리개미, 민냄새개미, 노랑잘록개미)들은 산불이 나지 않은 조사지와 자연적으로 식생이 복원되는 조사지에서 많이 발생한 반면, 개활지를 선호하는 종(예, 곰개미, 일본왕개미, 주름개미)들은 인위적으로 조림된 곳에서 많이 나타 났다. 다변량분석 결과는 인위적으로 조림된 곳이 자연적으로 식생이 복원된 곳 보다 개미군집이 산불 후에 더 많이 달라지는 것을 보여준다. 자연 복원된 조사지에서는 개미군집이 산불이 난 5-6년후에 산불 이전으로 회복되는 데 비해, 인공복원된 조사지에서는 회복에 약 25년이 소요될 것으 로 추정되었다.
Butterflies are commonly used for environmental monitoring to assess biodiversity changes in the world. Occurrence of butterflies were monitored by a line transect method in Gwangneung forest for 10 years from 2005 to 2014. Totally, 8,484 individuals of 96 species of butterflies were identified. Among them, two species Libythea celtis (2807 individuals) and Pieris melete (1517 individuals) were the most abundant species, followed by Argynnis paphia (381 individuals) and Neptis philyroides (277 individuals). Meanwhile, Pieris melete and Libythea celtis showed high occurrence frequency with 84.6% (99 times among the 117 monitoring times) and 76.9% (90 times) respectively, followed by Argynnis paphia (42.7%) and Pieris canidia (40.2%). Species richness and abundance were varied at different years, and they were slightly decreasing in recent years. Most species showed annual variation in their abundance. Species abundance distribution model showed a log-normal distribution.
Winter phenology (diapause and activity) of insects is expected to change more greatly compared with those of other seasons, because the temperature in winter increased higher than those in other seasons in the temperate regions. However, studies on changes of insect winter phenology due to climate warming are rare. It is expected that winter flights of flies (Diptera) will increase as climate warms. This study is aimed to predict the increase of fly winter flight according to temperature increase using the relationship between the flight and temperature. The survey on flies and weather (temperature and rainfall) was carried out in the Hongneung arboretum in Seoul. Flies were collected weekly from December 2012 to February 2013 using sweeping and Malaise trap. In the survey, 106 flies belonging to 28 morpho-species and 17 families were collected. Richness and abundance of flies were positively correlated with temperature. The increase of fly winter flight (richness and abundance) was projected according to temperature rise using the regression models for relationships between the fly flights and temperature.
The population of Myrmica ants, which is most abundant in high altitudinal areas in South Korea, is expected to decrease significantly due to climatic warming, whereas Aphaenogaster japonica population is expected to increase in these areas. The two ant groups are similar in shape, size, and ecology, indicating intensive competition in overlapping areas. To determine the competitions between the two groups, I investigated the ants at a high mountain (Mt. Gaebangsan) during two ant foraging seasons (2010 and 2011) using pitfall traps and bait traps along altitudinal gradients. Two Myrmica species (kotokui and kurokii) were present between 800 m to 1577 m, whereas A. japonica appeared up to 1200 m. Fights between ants were observed 22 times and fights between these two ant groups were most frequently found. Although a competitive hierarchy was not apparent, A. japonica appears to be dominant over Myrmica species in food competition when considering the more timid behavior of Myrmica species and my unpublished data. However, food discovery speed is greater in Myrmica species than in A. japonica, indicating a dominance-discovery tradeoff. The food discovery capability of A. japonica was greatly reduced at 1050 m elevation, which is around the elevational limit. This elevational suppression of food discovery capability was not found in Myrmica species.
Distribution and abundance of species are influenced by their environmental condition. Among various environmental factors, a vegetation is one of the most influential factors, because it is used as habitats as well as food resources. Arthropods including insects play a important role in forest ecosystems as grazers, scavenger, predators, etc. Deciduous and coniferous forests have different plant community composition, resulting in different environmental condition. In this study, we collected arthropod communities at two different deciduous and coniferous forest stands in the Mountain Gariwang. At each stand, three different sampling methods were used: soil core for soil macroinvertebrate, pitfall trap for wandering insects, and sweeping net for insects in the shrups. Therefore, sampling was conducted at vertical habitats in the forest. The results showed that there were no difference in the number of orders from soil at both coniferous and deciduous stands. However, the abundance was higher at coniferous stand than at deciduous stand. Collembola was the dominant taxa in soil. Meanwhile, there were no statistically significant differences of community composition between coniferous stand and deciduous stands. Multivariate analyses was conducted to characterize differences of communities at different stands as well as vertical distribution in forest.
In South Korea, ants are predicted to shift their distributions northwards and upwards. It was predicted that ant fauna will be changed dramatically in highlands due to the range shifts. The Mymica ants which are most abundant in high altitudinal areas in South Korea will be nearly disappeared there in 2050s, and replaced by Aphaenogaster japonica which is abundant in lowlands. It was recently found that A. japonica shifted upwards in Mt. Hanla in Jeju island, South Korea. Interestingly, A. japonica is similar in shape and size with the Myrmica species, which indicate niche overlap and resulting intensive competition. To find elevational change of competitions between two specie, we investigated ants during two ant foraging periods (2010 and 2011) in a high mountain (Mt. Gaebang) using pitfall traps and bait traps along elevational gradients. Ten ant species were collected from a.s.l. 800 m to a.s.l. 1577 m. Myrmica sp. 1 was most abundant (35% of total ants) and collected at all elevations. Myrmica sp. 2 (19.7%) occurred from 1000 m to 1577 m. Meanwhile, A. japonica occurred up to 1200 m. Fights between ants were observed 22 times; fights between these two species were most frequently found. Although, competitive hierarchy was not recognized due to a low frequency of interspecific encounters, A. japonica is likely to be superior over Myrmica species in food competition when considering the slower and more timid behavior of Myrmica species compared with A. japonica. Therefore, it is likely that A. japonica would replace easily Myrmica species in Korean highlands when thermal barrier (i.e., cold climate in high elevations) will be removed due to climate warming.
Distributions of ants are mainly dependent on temperature. Hence, global warming would lead to shifts of distribution and abundance in ants. We surveyed ants at 366 forest sampling sites in South Korea using pitfall traps to predict change of ant abundance. Abundances of ant species were projected on the projected temperature based on A1B climate scenario. Common species (> 10 % occurrence) were analyzed on the relationship between abundance and temperature, and 16 species of the common species were selected for projection of abundance owing to future climate warming. Abundance of the selected species were projected on 900 m2 grid cells in 2011 and 2060 using GIS tool. In the projection, 11 species are predicted to decrease in 2060, whereas 5 species are predicted to increase. Myrmica kotokui, a most dominant highland species is expected to decrease up to 2.5% of current abundance in 2060, whereas Pachycondyla chinensis is expected to increase up to 264%. This abrupt change of ants would lead to cascade effects on other organisms such as insects, plants, mushrooms, and birds, which would disturb various functions and services of forest ecosystems.
In the Northern Hemisphere, northward shifts due to global warming are apparent in various organisms such as butterflies, birds, and plants. In South Korea, ranges of butterflies are expected to shift northwards. We tested whether distribution limits of Korean butterflies shift northwards. We used two Korean butterfly atlases (1938-1950, 1977-2011) for analysis of the range shifts. Northern limits of southern species moved significantly northward (ca. 60 km) for 50 years, whereas southern limits of northern species did not significantly move northwards nor southwards. This finding parallels with other studies on butterflies and birds in Europe and North America.
It is expected that the successful nationwide reforestation and the increased temperature would greatly change butterfly fauna in South Korea. We compared current data (2002~2007) regarding abundance and presence of butterfly species at two sites in the central portion of the Korean Peninsula to data from late 1950s and early 1970s for the same sites. The expected changes were documented by abundance change of butterflies at two study sites in the previous study. Using the same data, the greatly changed species and the change of species presence were analyzed. Population changes of 99 butterfly species which occurred at both sites were significantly correlated between two sites. The greatly increased species included three Southern (S) species and one Northern (N) species. However, the greatly declined species included five N species and no S species. This change is coincided with the expectation from the northward movements of butterfly species due to global warming. The current status of the greatly changed species was discussed on the review with other studies. The binary data(presence/absence) in present study support the expected changes of butterfly species based on global warming and reforestation. The interactive effect of two environmental changes was also recognized as like the change of abundance in the previous study.
Pine wilt disease (PWD) represents a major threat to forest ecosystems worldwide. Although PWD is now better understood, effective control measures for this disease have still not been devised. Here, we report several years of field studies on preventative silvicultural control of PWD. Silvicultural control through preventative clear-cutting and the manual removal of logs was implemented between 2005 and 2009 in 16 Korean districts that had newly PWD-infected stands. Preventative clear-cutting of neighbouring asymptomatic pine trees (within a 10 to 50-m radius ofwilt trees) and the removal of felled logs or branches suppressed spread of PWD. Occurrences of PWD wilt pines in districts (city or county) subjected to this silvicultural control method were significantly reduced compared with those in districts using conventional controls (physical or chemical treatment of wilt pine trees). Through silvicultural control, PWD was successfully suppressed in 11 of 16 districts investigated. In contrast, successful control was achieved in only 1 among 18 districts subjected to conventional control. Our results will be of considerable interest to those engaged in the very difficult battle against the global spread of PWD.
Ant species were reported to have specific vertical distribution in high mountains in Korea. The vertical distribution was recognized in Hanla mountain being highest in South Korea using pitfall traps in 2006. This phenomena suggests that temperature may be a main factor for distribution of ant species, since 0.5~0.6℃ of temperature decrease per each 100 m of altitude. The present study was carried out to test this hypothesis. Ant communities were surveyed using pitfall traps (ten traps per each site) at 234 sites, which included 9 high mountains in South Korea. The vertical distribution of ant species were found in all the high mountains. Abundance data (probability of occurrence, %) of seventeen abundant ant species which occurred at more than 10% of the study sites were analyzed using multiples regression analysis with four independent factors such as temperature, precipitation, light intensity, and NDVI. As results of the regression analysis, temperature was most important in determining the abundance in 11 of 17 species. Light intensity was most important in 3 species, and precipitation in 1 species. In the 11 species being highly dependent on temperature, determination index (R2) of regression model with one factor of temperature was approximately 90% of determination index of the regression model with all four factors. On the base of dependence on temperature and of ecological characteristics (ground foraging), six species such as Paratrechina flavipes, Myrmica kotokui, Pachycondyla javana, Pristomyrmex pungens, Camponotus atrox, and Crematogaster osakensis were selected as bioindicator for global warming. In the bioindicator ant species, M. kotokui and C. atrox were predicted to decline in abundance and distribution in Korean peninsula as temperature increases, whereas other four species including P. flavipes, P. javana, P. pungens, C. osakensis were predicted to increase. Temperature-Distribution models were established in four most temperature-responsive species including P. flavipes, P. javana, P. pungens, and M. kotokui, and distribution maps of the species were made from the model. Reversely, temperature was estimated from ant data of five bioindicator species using regression model, of which R2 is 0.66.
We've collected litter-dwelling predatory arthropods (spiders and carabid beetles) by using pitfall traps at four different fire intensity treatment areas (control, ground fire, canopy fire, and canopy fire with plantation) at four different regional areas in 2005. We analyzed the arthropod community structures with PC-Ord for the difference of arthropod community among the various fire intensity treatments and control. Our objective was to verify if there was any difference between fired areas and non fired area (control) and between canopy fire with plantation and canopy fire without plantation. From our arthropod community structures, we found there was distinct community composition difference between fired areas and non-fired area as well as between control and canopy fire treatment with plantation or non-plantation. However, we are not sure yet that there was any distinct difference between control and ground fire treatments. Our results from the multivariate analysis, Non-parametric Multidimensional Scaling ordination, could be relatively conclude that the main difference of arthropod community between fired areas and non-fired areal and canopy fire with plantation or non-plantation was caused from the difference of arthropod habitat pattern such as litter depth, litter volumem, CWD cover or volume, and et. al. When we compared to control and other treatments, we could also conclude that the canopy fire treatment with non-plantation was relatively closed to control than the canopy fire treatment with plantation.
The p-type Te functional gradient material (FGM) was fabricated by hot-pressing the mechanically alloyed and the 0.5 at% powders. Also, the n-type FGM was processed by hot-pressing the mechanically alloyed and the 0.3 wt% Bi-doped PbTe powders. With larger than , the p-type FGM exhibited larger thermoelectric output power than those of the and the 0.5 at% alloys. For the n-type FGM, the thermoelectric output power superior to those of the and the 0.3 wt% Bi-doped PbTe was predicted at larger than .