Many Chinese people leave big cities for family reunions during the Chinese New Year （CNY）, which is the most important public holiday in China. However, how modem mass human migration during the CNY holiday affects...Many Chinese people leave big cities for family reunions during the Chinese New Year （CNY）, which is the most important public holiday in China. However, how modem mass human migration during the CNY holiday affects the urban heat island （UHI） is still un- known. Here, the authors investigate the role of modem human migration for the UHI effects during the CNY holiday for the period of 1992-2006 in Harbin City, Northeast China. The results show that during the CNY week, the UHI effects expressed as daily mean, maxi- mum, and minimum temperature differences between urban and rural stations averaged over the period of 1992-2006 are 0.65℃ （43%）, 0.31℃ （48%）, and 1.14℃ （71%） lower than during the background period （four weeks before and four weeks after the CNY week）, re- spectively. Our findings identify previously unknown impacts of modem mass human migration on the UHI effects based on a case study in Harbin City.展开更多
Prehistoric human history on the Tibetan Plateau is a hotly debated topic. Archaeological research on the plateau during the past few decades has enormously improved our understanding of the topic and makes it possibl...Prehistoric human history on the Tibetan Plateau is a hotly debated topic. Archaeological research on the plateau during the past few decades has enormously improved our understanding of the topic and makes it possible for us to consider the processes and mechanisms of prehistoric human migration to the region. By reviewing the published archaeological research on the Tibetan Plateau, we propose that the first people on the plateau initially spread into the He-Huang region from the Chinese Loess Plateau, and then moved to the low elevation Northeastern Tibetan Plateau and perhaps subsequently to the entire plateau. This process consisted of four stages.(1) During the climatic amelioration of the Last Deglacial period(15–11.6 ka BP), Upper Paleolithic hunter-gatherers with a developed microlithic technology first spread into the Northeastern Tibetan Plateau.(2) In the early-mid Holocene(11.6–6 ka BP), Epipaleolithic microlithic hunter-gatherers were widely distributed on the northeastern plateau and spread southwards to the interior plateau, possibly with millet agriculture developed in the neighboring low elevation regions.(3) In the mid-late Holocene(6–4 ka BP), Neolithic millet farmers spread into low elevation river valleys in the northeastern and southeastern plateau areas.(4) In the late Holocene(4–2.3 ka BP), Bronze Age barley and wheat farmers further settled on the high elevation regions of the Tibetan Plateau, especially after 3.6 ka BP. Finally, we suggest that all of the reported Paleolithic sites earlier than the LGM on the Tibetan Plateau need further examination.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41275089 and 41305071)the National Basic Research Program of China(Grant No.2012CB955604)Jingyong ZHANG was supported by the Jiangsu Collaborative Innovation Center for Climate Change
文摘Many Chinese people leave big cities for family reunions during the Chinese New Year （CNY）, which is the most important public holiday in China. However, how modem mass human migration during the CNY holiday affects the urban heat island （UHI） is still un- known. Here, the authors investigate the role of modem human migration for the UHI effects during the CNY holiday for the period of 1992-2006 in Harbin City, Northeast China. The results show that during the CNY week, the UHI effects expressed as daily mean, maxi- mum, and minimum temperature differences between urban and rural stations averaged over the period of 1992-2006 are 0.65℃ （43%）, 0.31℃ （48%）, and 1.14℃ （71%） lower than during the background period （four weeks before and four weeks after the CNY week）, re- spectively. Our findings identify previously unknown impacts of modem mass human migration on the UHI effects based on a case study in Harbin City.
基金supported by National Natural Science Foundation of China (Grant Nos. 41101087 & 41171168)the Project of Tracing Civilization Origin (Grant No. 2013BAK08B02)Primary Supports for Scientific Research of Lanzhou University (Grant Nos. LZUJBKY-2014-121, LZUJBKY-2016-159, LZUJBKY-2015-K09 & LZUJBKY-2014-120)
文摘Prehistoric human history on the Tibetan Plateau is a hotly debated topic. Archaeological research on the plateau during the past few decades has enormously improved our understanding of the topic and makes it possible for us to consider the processes and mechanisms of prehistoric human migration to the region. By reviewing the published archaeological research on the Tibetan Plateau, we propose that the first people on the plateau initially spread into the He-Huang region from the Chinese Loess Plateau, and then moved to the low elevation Northeastern Tibetan Plateau and perhaps subsequently to the entire plateau. This process consisted of four stages.(1) During the climatic amelioration of the Last Deglacial period(15–11.6 ka BP), Upper Paleolithic hunter-gatherers with a developed microlithic technology first spread into the Northeastern Tibetan Plateau.(2) In the early-mid Holocene(11.6–6 ka BP), Epipaleolithic microlithic hunter-gatherers were widely distributed on the northeastern plateau and spread southwards to the interior plateau, possibly with millet agriculture developed in the neighboring low elevation regions.(3) In the mid-late Holocene(6–4 ka BP), Neolithic millet farmers spread into low elevation river valleys in the northeastern and southeastern plateau areas.(4) In the late Holocene(4–2.3 ka BP), Bronze Age barley and wheat farmers further settled on the high elevation regions of the Tibetan Plateau, especially after 3.6 ka BP. Finally, we suggest that all of the reported Paleolithic sites earlier than the LGM on the Tibetan Plateau need further examination.
