The phenologies of plants and animals in snow-covered landscapes are expected to accelerate with global warming.However,there are few studies that have examined a range of unrelated taxa in alpine environments to dete...The phenologies of plants and animals in snow-covered landscapes are expected to accelerate with global warming.However,there are few studies that have examined a range of unrelated taxa in alpine environments to determine whether there is commonality in the proximate causes,synchrony in timing,or the direction of any changes.Records for five alpine animal species and two alpine plant species,chosen primarily for their visibility,were examined to determine their temporal response to regional climate warming.Over the 30-year period studied,they showed an array of different phenological responses.Plant flowering appeared linked to date of snow melt,whereas animal responses varied.Although having accelerated phenologies,two migratory bird species exhibited contrary changes;one to low-altitude warming regardless of snow conditions in the alpine zone (flame robin) and the other to state of the snowpack regardless of low-altitude temperatures (Richard's pipit).By contrast,the migratory bogong moth arrived significantly later over the years with no apparent explanatory climatic cause.Although bogong moths are not responding to earlier snow melt,insectivorous predators on the ground are.This could lead to a serious mismatch in timing at different trophic levels,putting pressure on endangered vertebrates.Emergence of locally wintering insect species,March flies and Macleay's swallowtails,were not significantly related to measured climatic parameters over the study period.A consequence of the disparate responses to climate warming recorded here is the questionable value of 'indicator species' to examine the impact of climate warming on alpine ecosystems.展开更多
A 109.9 m ice core was extracted at a location about 300 m away from the Dome A summit （80°00′S, 77°21″E） by the Chinese team of the International Trans-Antarctic Science Expedition （ITASE） during the ...A 109.9 m ice core was extracted at a location about 300 m away from the Dome A summit （80°00′S, 77°21″E） by the Chinese team of the International Trans-Antarctic Science Expedition （ITASE） during the 21st Chinese National Antarctica Research Expedition （CHINARE） in January 2005. Two independent methods were used for dating the ice core, volcanic event markers shown by prominent non-sea-salt sulfate （nss-SO4^2-） and the Herron and Langway （H-L） firn densification model. Six promi- nent volcanic events （Agung 1963 AD, Tambora 1815 AD, Kuwae 1453 AD, Unknown 1259 AD, Taupo 186 AD and Pinatubo 1050 BC） were identified by comparison with other Antarctic ice cores. Based on the mean accumulation rates be- tween adjacent events, we estimate the age at the tim pore close-off depth （102 m） was 3516±100 a BP. This is the oldest close-off age ever reported from the Antarctic and the Greenland ice sheets. Calculations using the H-L model show that the age at the same depth is 3581±100 a BP. The two dating techniques differ by 65 years, or -1.8% of the record. We calculated the bottom age of the ice core as 4009±150 a BP using the volcanic dating method and 4115±150 a BP using the H-L model method.展开更多
文摘The phenologies of plants and animals in snow-covered landscapes are expected to accelerate with global warming.However,there are few studies that have examined a range of unrelated taxa in alpine environments to determine whether there is commonality in the proximate causes,synchrony in timing,or the direction of any changes.Records for five alpine animal species and two alpine plant species,chosen primarily for their visibility,were examined to determine their temporal response to regional climate warming.Over the 30-year period studied,they showed an array of different phenological responses.Plant flowering appeared linked to date of snow melt,whereas animal responses varied.Although having accelerated phenologies,two migratory bird species exhibited contrary changes;one to low-altitude warming regardless of snow conditions in the alpine zone (flame robin) and the other to state of the snowpack regardless of low-altitude temperatures (Richard's pipit).By contrast,the migratory bogong moth arrived significantly later over the years with no apparent explanatory climatic cause.Although bogong moths are not responding to earlier snow melt,insectivorous predators on the ground are.This could lead to a serious mismatch in timing at different trophic levels,putting pressure on endangered vertebrates.Emergence of locally wintering insect species,March flies and Macleay's swallowtails,were not significantly related to measured climatic parameters over the study period.A consequence of the disparate responses to climate warming recorded here is the questionable value of 'indicator species' to examine the impact of climate warming on alpine ecosystems.
基金supported by National Natural Scientific Foundation of China (Grant Nos.40776002,40825017,41171052)the Hundred Talent Project of Chinese Academy of Sciences,the Polar Scientific Explore Organizing Committee Foundation (Grant Nos. 20080202,0852H71001)State Oceanic Administration of People’s Republic of China Project on Climate in Polar Regions (Grant Nos.CHINARE2012-04-04 and CHINARE2012- 02-02)
文摘A 109.9 m ice core was extracted at a location about 300 m away from the Dome A summit （80°00′S, 77°21″E） by the Chinese team of the International Trans-Antarctic Science Expedition （ITASE） during the 21st Chinese National Antarctica Research Expedition （CHINARE） in January 2005. Two independent methods were used for dating the ice core, volcanic event markers shown by prominent non-sea-salt sulfate （nss-SO4^2-） and the Herron and Langway （H-L） firn densification model. Six promi- nent volcanic events （Agung 1963 AD, Tambora 1815 AD, Kuwae 1453 AD, Unknown 1259 AD, Taupo 186 AD and Pinatubo 1050 BC） were identified by comparison with other Antarctic ice cores. Based on the mean accumulation rates be- tween adjacent events, we estimate the age at the tim pore close-off depth （102 m） was 3516±100 a BP. This is the oldest close-off age ever reported from the Antarctic and the Greenland ice sheets. Calculations using the H-L model show that the age at the same depth is 3581±100 a BP. The two dating techniques differ by 65 years, or -1.8% of the record. We calculated the bottom age of the ice core as 4009±150 a BP using the volcanic dating method and 4115±150 a BP using the H-L model method.
