Flowering onset has attracted much attention in ecological research as an important indicator of climate change.Generally,warmer temperatures advance flowering onset.The effect of climate warming on flowering onset is...Flowering onset has attracted much attention in ecological research as an important indicator of climate change.Generally,warmer temperatures advance flowering onset.The effect of climate warming on flowering onset is more pronounced in spring because the difference between atmospheric and water temperatures creates more rapid convection than in other seasons.We analyzed the correlation between 73 species of spring woody plants in Hongneung Arboretum in Seoul,South Korea and the spring minimum temperature and average precipitation over the past 50 years(1968–2018).The spring minimum temperature and average precipitation have increased over the past 50 years,resulting in the advance of the first flowing date(FFD)in all 73 species by 8.5 days on average.A comparison of FFD changes over time by dividing the survey period into three time periods confirmed the advance of the FFD in 50 species(68%of investigated species)by 11.1 days on average in both Period 2(1999–2008)and Period 3(2009–2018)relative to Period 1(1968–1975).Additionally,a delay of the FFD by 3.2 days on average was observed in 8 species.The FFD of Lonicera chrysantha(Caprifoliaceae)advanced by over 40 days and was highly correlated with the increased spring minimum temperature.Analysis of the sensitivity of plant responses to climate change revealed that a temperature rise of 1℃ was associated with an FFD advance of 1.2 days in all species.The species that was most sensitive to temperature change was Spiraea pubescens for.leiocarpa(Rosaceae),whose FFD advanced by 4.7 days per 1℃ temperature rise.Each increase in precipitation by 1 mm was found to result in a 0.1-day advance of the FFD of all species.Prunus tomentosa(Rosa-ceae)was the most sensitive species,that advanced by 2.6 days for each 1 mm increase in precipitation.Thus,for all species,the FFD was more sensitive to the change in temperature than in precipitation.Assuming that the current greenhouse gas(GHGs)emission levels or atmospheric CO_(2) concentration is maintained,Seoul’s spring minimum temperature is projected to rise by 2.7℃ over the next 50 years.Accordingly,considering only the global temperature change,the mean FFD of the study’s 73 species is projected to advance by an additional 3.4 days.展开更多
The calling activity of anurans is influenced by environmental variables and calls produced by syntopic amphibians,among other variables.Some variables have a strong influence,such as temperature and predation dilutio...The calling activity of anurans is influenced by environmental variables and calls produced by syntopic amphibians,among other variables.Some variables have a strong influence,such as temperature and predation dilution,while others may have a periodical influence such as the moon cycle.Here,we hypothesised that the calling activity of the Suweon treefrog,Dryophytes suweonensis,is restricted by specific environmental variables but reinforced by the calling activity of specific syntopic anurans.Within the criteria set by the experimental design,D.suweonensis calling activity was significantly influenced by moon phase,temperature,date,time to sunset and the calling activity of Pelophylax nigromaculatus and D.japonicus.These variables are expected to be related to chorus size,predation,breeding phenology and competition,suggesting a broad plasticity in the calling activity of the species.展开更多
Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximit...Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximity.Because no extra traits need to evolve,spatial and temporal differentiation may readily take place to complement other isolating mechanisms.Two closely related treefrog species occur together in Korea:the endangered Hyla suweonensis and the widespread Hyla japonica.Advertisement calls are differentiated,but it is unclear whether call difference is sufficient for reproductive isolation.We tracked individuals of both species to study fine-scale differentiation in microhabitat use in the diel cycle of the breeding season using a harmonic direction finder.tracking male movement patterns of both species revealed spatial and temporal differentiation in microhabitat use for calling and resting during the breeding season.Males of both H.suweonensis and H.japonica occurred in all 5 microhabitats identified in this study:rice paddy,ground,buried,grass and bush.Both treefrog species showed general similarities in calling from rice paddies and resting in grass and bush.However,H.suweonensis moved into rice paddies and produced advertisement calls 3 h earlier than H.japonica.These differences likely minimize contact between the species and provide an additional isolating mechanism.In addition,the activity of H.suweonensis may be contributing to the decline of this species,as resting in grass would increase dangers from predatory birds and habitat disturbance.展开更多
基金This study was supported by the BK21 Plus Program(Creative Academy of Ecoscience,31Z20130012990)funded by the Ministry of Education and National Research Foundation of Korea.
文摘Flowering onset has attracted much attention in ecological research as an important indicator of climate change.Generally,warmer temperatures advance flowering onset.The effect of climate warming on flowering onset is more pronounced in spring because the difference between atmospheric and water temperatures creates more rapid convection than in other seasons.We analyzed the correlation between 73 species of spring woody plants in Hongneung Arboretum in Seoul,South Korea and the spring minimum temperature and average precipitation over the past 50 years(1968–2018).The spring minimum temperature and average precipitation have increased over the past 50 years,resulting in the advance of the first flowing date(FFD)in all 73 species by 8.5 days on average.A comparison of FFD changes over time by dividing the survey period into three time periods confirmed the advance of the FFD in 50 species(68%of investigated species)by 11.1 days on average in both Period 2(1999–2008)and Period 3(2009–2018)relative to Period 1(1968–1975).Additionally,a delay of the FFD by 3.2 days on average was observed in 8 species.The FFD of Lonicera chrysantha(Caprifoliaceae)advanced by over 40 days and was highly correlated with the increased spring minimum temperature.Analysis of the sensitivity of plant responses to climate change revealed that a temperature rise of 1℃ was associated with an FFD advance of 1.2 days in all species.The species that was most sensitive to temperature change was Spiraea pubescens for.leiocarpa(Rosaceae),whose FFD advanced by 4.7 days per 1℃ temperature rise.Each increase in precipitation by 1 mm was found to result in a 0.1-day advance of the FFD of all species.Prunus tomentosa(Rosa-ceae)was the most sensitive species,that advanced by 2.6 days for each 1 mm increase in precipitation.Thus,for all species,the FFD was more sensitive to the change in temperature than in precipitation.Assuming that the current greenhouse gas(GHGs)emission levels or atmospheric CO_(2) concentration is maintained,Seoul’s spring minimum temperature is projected to rise by 2.7℃ over the next 50 years.Accordingly,considering only the global temperature change,the mean FFD of the study’s 73 species is projected to advance by an additional 3.4 days.
基金financially supported by research grants from the National Research Foundation of Korea (2017R1A2B2003579)the Rural Development Administration (PJ012285) to Y JANGa grant from the French Rotary Club Lectoure-Fleurance to A Borzée。
文摘The calling activity of anurans is influenced by environmental variables and calls produced by syntopic amphibians,among other variables.Some variables have a strong influence,such as temperature and predation dilution,while others may have a periodical influence such as the moon cycle.Here,we hypothesised that the calling activity of the Suweon treefrog,Dryophytes suweonensis,is restricted by specific environmental variables but reinforced by the calling activity of specific syntopic anurans.Within the criteria set by the experimental design,D.suweonensis calling activity was significantly influenced by moon phase,temperature,date,time to sunset and the calling activity of Pelophylax nigromaculatus and D.japonicus.These variables are expected to be related to chorus size,predation,breeding phenology and competition,suggesting a broad plasticity in the calling activity of the species.
基金supported financially by the National Research Foundation of Korea(grant number 2012R1A2A2A01046977).
文摘Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximity.Because no extra traits need to evolve,spatial and temporal differentiation may readily take place to complement other isolating mechanisms.Two closely related treefrog species occur together in Korea:the endangered Hyla suweonensis and the widespread Hyla japonica.Advertisement calls are differentiated,but it is unclear whether call difference is sufficient for reproductive isolation.We tracked individuals of both species to study fine-scale differentiation in microhabitat use in the diel cycle of the breeding season using a harmonic direction finder.tracking male movement patterns of both species revealed spatial and temporal differentiation in microhabitat use for calling and resting during the breeding season.Males of both H.suweonensis and H.japonica occurred in all 5 microhabitats identified in this study:rice paddy,ground,buried,grass and bush.Both treefrog species showed general similarities in calling from rice paddies and resting in grass and bush.However,H.suweonensis moved into rice paddies and produced advertisement calls 3 h earlier than H.japonica.These differences likely minimize contact between the species and provide an additional isolating mechanism.In addition,the activity of H.suweonensis may be contributing to the decline of this species,as resting in grass would increase dangers from predatory birds and habitat disturbance.
