• 제목/요약/키워드: phenology

검색결과 223건 처리시간 0.027초

Abiotic effects on calling phenology of three frog species in Korea

  • Yoo, Eun-Hwa;Jang, Yi-Kweon
    • Animal cells and systems
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    • 제16권3호
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    • pp.260-267
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    • 2012
  • Calling behavior is often used to infer breeding patterns in anurans. We studied the seasonal and diel calling activities of anuran species in a wetland in central Korea to determine the calling season and to evaluate the effects of abiotic factors on male calling. Acoustic monitoring was used in which frog calls were recorded for a full day, once a week, throughout an entire year. Using acoustic monitoring, we identified three frog species in the study site. Males of Rana dybowskii called in late winter and early spring; we thus classified this species as a winter/spring caller. The results of binary logistic regression showed that temperature, relative humidity, and 1-day lag rainfall were significant factors for male calling in R. dybowskii. Temperature and relative humidity were important factors for the calling activity of R. nigromaculata, whereas 24-h rainfall and 1-day lag rainfall were not significant. Thus, we determined R. nigromaculata to be a summer caller independent of weather. In Hyla japonica, relative humidity, 24-h rainfall, and 1- day lag rainfall were significant for male calling, suggesting that this species is a summer caller dependent on local rain.

Growth and Maturation of Natural Population of Meristotheca papulosa in Jeju Island (제주도 유용 해조류 갈래곰보(Meristotheca papulosa) 야외개체군의 생장과 성숙)

  • Kim, Bo Yeon;Choi, Han Gil;Ko, Jun-Cheol
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제52권1호
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    • pp.59-66
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    • 2019
  • The growth and maturation pattern of a commercial and endemic red algae Meristotheca papulosa were investigated in Jeju Island. Ecological researches were performed in a natural population of 10 m water depth in Sinheung from march 2014 to November 2015. Maximal blade length and weight of M. papulosa were 8.7 cm and 5.49 g in July 2014 and 10.7 cm and 10.17 g in September 2015, respectively. Growth in blade area of the species reached a maximum of $43.84cm^2$ and $67.41cm^2$ in July 2014 and 2015, respectively. Thalli in the field population were rarely observed from October to December but new recruits were found from January, following year. Carposporophytes were observed from June to September when bottom seawater temperatures were around $20^{\circ}C$. At the study site, seawater temperature was in the range of $14.9-25.7^{\circ}C$. Growth parameters of M. papulosa and relative abundance of carposporophytes showed significant correlation with environmental factors (temperature, salinity, DIN). In this result, we clarified the growth and maturation period of M. palpulosa, and provided effective data on the protection and management of natural populations and basic data for mass culture of the alga.

Phenology of Zostera caespitosa in Tongyeong on the coast of Korea

  • Yoon, Joon-Sik;Kim, Nam-Gil
    • Fisheries and Aquatic Sciences
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    • 제24권3호
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    • pp.121-128
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    • 2021
  • The variations of morphological features, density and biomass of vegetative shoots and characteristics of reproductive shoots of Zostera caespitosa were examined in Tongyeong, Korea. Morphological features such as leaf length, width and sheath length of Z. caespitosa showed significant seasonal variation (p < 0.001). The highest aboveground value was recorded in late spring to summer and the lowest value in winter. Density and biomass also showed seasonal variations. Annual average shoot density and biomass of Z. caespitosa were recorded as 1,223.4 leaf m-2 and 5,956.9 g w.w.m-2, respectively, and had the highest value in June and lowest values in November and January. Reproductive shoots were observed from April (13℃) to June (21℃). Pistils erected outside sheath, anther dehiscing and small embryos were found in April. Mature fruit and released seeds were found in May and June. These results suggest that this species had a high growth rate in late spring and early summer (15℃-20℃). Reproductive shoots of Z. caespitosa may initially appear at about 10℃ in spring and seed have been released at about 20℃ in fall.

Effect of elevated pCO2 on thermal performance of Chattonella marina and Chattonella ovata (Raphidophyceae)

  • Lim, Myeong Hwan;Lee, Chung Hyeon;Min, Juhee;Lee, Hyun-Gwan;Kim, Kwang Young
    • ALGAE
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    • 제35권4호
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    • pp.375-388
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    • 2020
  • Ocean acidification and warming, identified as environmental concerns likely to be affected by climate change, are crucial determinants of algal growth. The ichthyotoxic raphidophytes Chattonella species are responsible for huge economic losses and environmental impact worldwide. In this study, we investigated the impact of CO2 on the thermal performance curves (TPCs) of Chattonella marina and Chattonella ovata grown under temperatures ranging from 13 to 34℃ under ambient pCO2 (350 μatm) and elevated pCO2 (950 μatm). TPCs were comparable between the species or even between pCO2 levels. With the exception of the critical thermal minimum (CTmin) for C. ovata, CTmin for C. marina and the thermal optimum (Topt) and critical thermal maximum (CTmax) for both species did not change with elevation of pCO2 levels. While CO2 enrichment increased the maximum photosynthetic rates (Pmax) up to 125% at the Totp of 30℃, specific growth rates were not significantly different under elevated pCO2 for the two species. Overall, C. ovata is likely to benefit from climate change, potentially widening its range of thermal tolerance limit in highly acidic waters and contributing to prolonged phenology of future phytoplankton assemblages in coastal waters.

Thermal plasticity of growth and chain formation of the dinoflagellates Alexandrium affine and Alexandrium pacificum with respect to ocean acidification

  • Lee, Chung Hyeon;Min, Juhee;Lee, Hyun-Gwan;Kim, Kwang Young
    • ALGAE
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    • 제36권4호
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    • pp.285-298
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    • 2021
  • The amount of CO2 absorbed by the oceans continues to rise, resulting in further acidification, altering some functional traits of phytoplankton. To understand the effect of elevated partial pressures of CO2 (pCO2) on functional traits of dinoflagellates Alexandrium affine and A. pacificum, the cardinal temperatures and chain formation extent were examined under two pCO2 (400 and 1,000 µatm) over the range of temperature expected to be associated with growth. The growth rate and chain formation extent of A. affine increased with higher pCO2, showing significant changes in cardinal temperatures and a substantial increase in middle chain-length (4-8 cells) fractionation under elevated pCO2 condition. By contrast, there were no significant differences in specific growth rate and any chain-length fractionation of A. pacificum between ambient and elevated pCO2 conditions. The observed interspecies variation in the functional traits may reflect differences in ability of species to respond to environmental change with plasticity. Moreover, it allows us to understand the shifting biogeography of marine phytoplankton and predict their phenology in the Korea Strait.

Nineteen new records of plant species including two new genera recorded from the Bhutan Himalayas

  • DORJI, Rinchen;PHUENTSHO, Phuentsho;DORJI, Kencho;TSHEWANG, Sangay;WANGDI, Phuntsho;TOBGAY, Kezang;GYELTSHEN, Nima;GYELTSHEN, Choki
    • Korean Journal of Plant Taxonomy
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    • 제52권3호
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    • pp.173-183
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    • 2022
  • Through the collection of herbarium specimens in Bhutan over the years, new plant species are discovered nearly annually. Thus, this paper reports two new genera and 19 new records of flowering plant species from Bhutan. The new genera include Eurycorymbus of the family Sapindaceae and Homalium of the family Salicaceae. The new records of plant species are Eranthemum erythrochilum (Acanthaceae), Hemidesmus indicus (Apocynaceae), Ilex umbellulata (Aquifoliaceae), Canarium strictum (Burseraceae), Ehretia acuminate (Boraginaceae), Vaccinium sikkimense (Ericaceae), Nothapodytes foetida (Icacinaceae), Machilus edulis (Lauraceae), Grewia asiatica (Malvaceae), Hibiscus fragrans (Malvaceae), Cipadessa baccifera (Meliaceae), Baccaurea javanica (Phyllanthaceae), Canthiumera glabra (Rubiaceae), Homalium napaulense (Salicaceae), Eurycorymbus cavaleriei (Sapindaceae), Acmella radicans (Asteraceae), Silene latifolia (Caryophyllaceae), Cleome rutidosperma (Cleomaceae), and Cuphea carthagenensis (Lythraceae). Morphological determinations of the genera and species were carried out at the National Herbarium (THIM) of the National Biodiversity Centre of Bhutan. Brief descriptions of the species, phenology, and photo plates are provided in this annotated checklist.

Development of K-Maryblyt for Fire Blight Control in Apple and Pear Trees in Korea

  • Mun-Il Ahn;Hyeon-Ji Yang;Sung-Chul Yun
    • The Plant Pathology Journal
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    • 제40권3호
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    • pp.290-298
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    • 2024
  • K-Maryblyt has been developed for the effective control of secondary fire blight infections on blossoms and the elimination of primary inoculum sources from cankers and newly emerged shoots early in the season for both apple and pear trees. This model facilitates the precise determination of the blossom infection timing and identification of primary inoculum sources, akin to Maryblyt, predicting flower infections and the appearance of symptoms on various plant parts, including cankers, blossoms, and shoots. Nevertheless, K-Maryblyt has undergone significant improvements: Integration of Phenology Models for both apple and pear trees, Adoption of observed or predicted hourly temperatures for Epiphytic Infection Potential (EIP) calculation, incorporation of adjusted equations resulting in reduced mean error with 10.08 degree-hours (DH) for apple and 9.28 DH for pear, introduction of a relative humidity variable for pear EIP calculation, and adaptation of modified degree-day calculation methods for expected symptoms. Since the transition to a model-based control policy in 2022, the system has disseminated 158,440 messages related to blossom control and symptom prediction to farmers and professional managers in its inaugural year. Furthermore, the system has been refined to include control messages that account for the mechanism of action of pesticides distributed to farmers in specific counties, considering flower opening conditions and weather suitability for spraying. Operating as a pivotal module within the Fire Blight Forecasting Information System (FBcastS), K-Maryblyt plays a crucial role in providing essential fire blight information to farmers, professional managers, and policymakers.

Relationship between the Time and Duration of Flowering in Several Woody Plants in Springtime

  • Min, Byeong-Mee;Lee, Ji-Sook;Jeong, Sang-Jin
    • Journal of Ecology and Environment
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    • 제31권2호
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    • pp.139-146
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    • 2008
  • To clarify the relationship between the timing and the duration of flowering among populations, plants, and individual flowers, the dates of flower budding, flowering and deflowering were monitored for ten woody species from March 1 to June 30, in 2005, 2006 and 2007, in temperate deciduous forests at three sites of Namsan, and individual plants from seven woody species were monitored from March 1 to May 31, in 2006. Total durations of flower budding, flowering, and deflowering varied among the plant species. Three durations of these phenological stages of Stephanandra incisa were the longest (74 days, 109 days, and 101 days, respectively), and those of Prunus serrulata var. spontanea were the shortest (7 days, 7 days, and 4 days, respectively). For each species, phenological durations varied among years but were similar among the study sites in the same year. There was no relationship between flowering time and flowering duration on the population level. On the plant level, the duration of flower budding was over 11 days in all specie; S. incisa had the longest duration (73.3 days), and that of Styrax japonica was long as well (29.0 days), while that of Prunus leveilleana was the shortest (11.3 days). The longer the mean flower budding duration, the greater the difference among the plants within a species. The flowering duration of for S. incisa was 92.2 days, while that of Forsythia koreana was 27.2 days. The flowering durations of all other species were $10{\sim}20$ days. The deflowering duration was 92.0 days in S. incisa and <15 days in all other species. Differences among the plants in deflowering duration were smaller than those of the other phenological stages. In the species that flowered in April, the correlation coefficient between the flowering duration and the first flowering date was negative and significant. However, in the species that flowered in May, the correlation between flowering duration and the first flowering date was not significant. For individual plants of all species except for S. alnifolia, the earlier the flowering time, the longer the flowering duration. Differences between flowering time and flowering duration across years were significant in six species.

Development of the Environmental Impact Assessment Techniques for the Grading of Rareness in Plant (식물의 희소성 평가를 위한 환경영향평가기법 개발)

  • Lee, You Mi
    • Journal of Environmental Impact Assessment
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    • 제6권2호
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    • pp.153-164
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    • 1997
  • This study was conducted to develop the new Environmental Impact Assessment techniques for the grading of rareness in plant. 17 EISs which were submitted in 1996 were analyzed to know the problems in existent EIA techniques for the conservation of rare plants. Category of rare plant was reevaluated and evaluation technique for the grading of rareness in plant was developed. The results obtained from this study were as follows: 1. The evaluation technique of rareness in plant was not reflected in the current preparation provision for EIS. And t his fact also appeared in most of the EIS which were reexamined in this study. 2. The category of rare species which have been considered as the subject of protection in EIA have to be enlarged to more than legally protected species designated by MOE. 3. The taxonomic characteristics and status of species, characteristics of population, geographical characters, extent of threat and its possibility by man resulted from the habitat loss were investigated. Each item was endowed scores from 1 to 5 and all the scores were summed, and then this value was used to evaluate the order of conservation. 4. Conservation measures for the rare plants have to be applied according to the levels of rareness grade, and they are absolute conservation, in situ conservation, transplanting and ex situ conservation, post observation and none by the levels from A to E. 5. Considering the phenology of rare plants, investigation for the rare plants have to be made a1 least three times. 6. Size of the MVP(Minimum Viable Population), pollination ecology also have to be considered for the conservation of rare plants. And in the case of adopting ex situ conservation measure, the site and methods for the conservation of rare plants have to be proposed in detail.

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A Comparison of the Land Cover Data Sets over Asian Region: USGS, IGBP, and UMd (아시아 지역 지면피복자료 비교 연구: USGS, IGBP, 그리고 UMd)

  • Kang, Jeon-Ho;Suh, Myoung-Seok;Kwak, Chong-Heum
    • Atmosphere
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    • 제17권2호
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    • pp.159-169
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    • 2007
  • A comparison of the three land cover data sets (United States Geological Survey: USGS, International Geosphere Biosphere Programme: IGBP, and University of Maryland: UMd), derived from 1992-1993 Advanced Very High Resolution Radiometer(AVHRR) data sets, was performed over the Asian continent. Preprocesses such as the unification of map projection and land cover definition, were applied for the comparison of the three different land cover data sets. Overall, the agreement among the three land cover data sets was relatively high for the land covers which have a distinct phenology, such as urban, open shrubland, mixed forest, and bare ground (>45%). The ratios of triple agreement (TA), couple agreement (CA) and total disagreement (TD) among the three land cover data sets are 30.99%, 57.89% and 8.91%, respectively. The agreement ratio between USGS and IGBP is much greater (about 80%) than that (about 32%) between USGS and UMd (or IGBP and UMd). The main reasons for the relatively low agreement among the three land cover data sets are differences in 1) the number of land cover categories, 2) the basic input data sets used for the classification, 3) classification (or clustering) methodologies, and 4) level of preprocessing. The number of categories for the USGS, IGBP and UMd are 24, 17 and 14, respectively. USGS and IGBP used only the 12 monthly normalized difference vegetation index (NDVI), whereas UMd used the 12 monthly NDVI and other 29 auxiliary data derived from AVHRR 5 channels. USGS and IGBP used unsupervised clustering method, whereas UMd used the supervised technique, decision tree using the ground truth data derived from the high resolution Landsat data. The insufficient preprocessing in USGS and IGBP compared to the UMd resulted in the spatial discontinuity and misclassification.