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Wood use and forest management by Neolithic millet farmers at the Xinglong site,northern China

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Science China Earth Sciences 2024年第6期67卷 1910-1921页

作者： Hui SHEN Zhenwei QIU keliang zhao Xinying ZHOU Xiaoqiang LI Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China National Museum of China Beijing 100006China University of Chinese Academy of Sciences Beijing 100049China

The origin and development of agriculture and its relationship with climate change are hotly debated topics among environmental *** this study,we analyzed wood charcoal materials from the Neolithic Xinglong site in northern China in order to understand the woody vegetation around the site and how early millet farmers shaped local *** results suggest that the area around the Xinglong sites during 8700-7000 yr BP was primarily woodlands,including Prunus sibirica shrubs,Ulmus and Acer forests,and Populus stands near *** 8000 to 7000 yr BP,the warm and humid climate probably contributed to the expansion of Acer,Rhamnus,and Juniperus,and may have facilitated the development of early millet *** these ancient wood fragments that we studied,the high percent of Prunus charcoal appears to indicate an abundance of fruit trees,which might have constituted the main component of local ***,the wood taxa illustrate the existence of a variety of ecological habitats,and it is logical to assume that people made full use of the locally available wood ***,Populus and Ulmus were the dominant sources of *** results of tree-ring curvature analyses indicate that people mainly collected trunks or large branches of Ulmus,Populus,Acer,and Juniperus *** interpret the increasing use of Prunus twigs and the declining percentage of Prunus charcoal in the period between 8000-7000 yr BP as indicating that people started to protect and manage wild fruit *** may have started pruning to acquire more food resources as part of the cultural responses and adaptation strategies employed by these early millet cultivators.

关键词： Xinglong site Wood charcoal Wood use Woodland management

Increased winter-spring precipitation from the last glaciation to the Holocene inferred from a δ^(13)C_(org) record from Yili Basin(Xinjiang, NW China)

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Science China Earth Sciences 2019年第7期62卷 1125-1137页

作者： keliang zhao Xiaoqiang LI Hai XU Xingying ZHOU John DODSON Junchi LIU Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment Institute of Surface-Earth System Science Tianjin University School of Earth Atmospheric and Life Sciences University of Wollongong Institute of Earth Environment Chinese Academy of Sciences

The nature and dynamics of climate change in central Asia since the late Pleistocene are controversial. Moreover,most of the published studies focus mainly on the evolution of moisture conditions, and there have been few attempts to address changes in seasonality. In this study, records of δ^(13)C_(org), TOC, TN, C/N and grain size were obtained from lacustrine sediments at Yili Basin, Xinjiang, NW China. Our aim was to reconstruct the trend in seasonality of precipitation from the last glaciation to the Holocene. The organic matter content of the sediments is derived predominantly from terrestrial plants. The δ^(13)C_(org)values vary from-19.4‰ to-24.8‰, indicating that the vegetation was dominated by C_3 plants. Winter-spring precipitation is identified as the factor determining the relative proportions of C_3 and C_4 plants in the region. A negative trend in δ^(13)C_(org)corresponding to an increase in the relative abundance of C_3 plants indicate a trend of increasing winter-spring precipitation from the last glaciation to the Holocene. The increased incidence of wintertime storms in the interior of Asia is suggested to result in the increase of winterspring precipitation in the Holocene.

关键词： Organic matter Central Asia C3 and C4 plants Seasonality changes Winter-spring precipitation

Modern pollen and vegetation relationships in the Yili Basin,Xinjiang, NW China

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Chinese Science Bulletin 2013年第30期58卷 4133-4142页

作者： zhao keliang LI XiaoQiang Key Laboratory of Vertebrate Evolution and Human Origin of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences

Fifty-six surface pollen samples from different vegetation zones in the Yili Basin,western Tianshan Mountains,Xinjiang were analyzed to examine the relationships between the surface pollen assemblages and the original vegetation.A pollen analysis and a vegetation investigation with a discriminant analysis show that the pollen assemblages greatly differ across disparate vegetation *** pollen taxa can be used as significant types for vegetation reconstruction in the *** taxa were the most abundant in the surface pollen *** pollen percentages were greater than 1%in Cupressaceae *** than5%of Picea pollen indicates the growth of a Picea forest within 5 *** subalpine meadow that is distributed widely in the basin is characterized by high content of Artemisia,Chenopodiaceae,Poaceae,Picea,Asteraceae,Taraxacum and Arenaria pollen *** Artemisia-Chenopodiaceae-Poaceae-Cannabaceae pollen assemblages indicate the presence of montane steppe in the *** and Chenopodiaceae pollen dominate the desert steppe and Populus *** pollen percentages were greater than 60%in the Artemisia desert,whereas Chenopodiaceae pollen percentages exceeded 65%in the Chenopodiaceae *** Artemisia/Chenopodiaceae(A/C)ratios reflect the vertical moisture changes in the Yili *** mean A/C ratios were greater than 1.2 in the subalpine meadow and montane steppe that occupy the humid zone in the *** ratios were between1 and 1.2 in the Cupressaceae shrubs,desert steppe,Populus forest and floodplain *** ratios were less than 0.5 in the Chenopodiaceae desert,which is an arid environment.

关键词：花粉分析伊犁盆地植被带新疆亚高山草甸孢粉组合中国西北

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Investigation of the ultrastructural characteristics of foxtail and broomcorn millet during carbonization and its application in archaeobotany

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Chinese Science Bulletin 2011年第14期56卷 1495-1502页

作者： YANG Qing LI XiaoQiang ZHOU XinYing zhao keliang JI Ming SUN Nan State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi 'an 710075 China The Laboratory of Human Evolution. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences. Beijing 100044 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008. China

Fossilized caryopses (or grains) of foxtail millet (Setaria italica) and broomcorn millet (Panicum miliaceum) are important archaeobotanical materials for the study of early human agricultural *** morphology and ultrastructural characteristics of carbonized modern millets caryopses treated in a drying oven and burning in a field were investigated at different temperatures to study how fossilized millets are *** caryopses shrank gradually at temperatures below 200°C,and starch granules in the endosperm retained their crystalline *** 250°C the foxtail millet caryopses expanded,whereas the broomcorn millet caryopses were greatly *** this temperature,the structure of the starch granules of both millets became *** 300°C the caryopses partially turned to ash and became porous,and the ultrastructure of the starch granules was transformed into alveolate *** caryopses from the prehistoric storage cellar at the Beiniu Site retained their crystalline structure and were formed by the dehydrating effect of carbonization,indicating that water molecules were not involved in the starch *** results of a field burning experiment demonstrated that the ultrastructure of carbonized caryopses placed on the ground under the fire was *** amorphous ultrastructure of the carbonized caryopses recovered from the archaeological layers is consistent with the expected structure of caryopses that have been carbonized at 250°***,we suggest that the recovered caryopses were formed at about 250°C by baking rather than by burning in an open fire.

关键词：超微结构特征谷子碳化淀粉颗粒黍燃烧实验晶体结构农业活动

Early agricultural development and environmental effects in the Neolithic Longdong basin(eastern Gansu)

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Chinese Science Bulletin 2011年第8期56卷 762-771页

作者： ZHOU XinYing LI XiaoQiang zhao keliang DODSON John SUN Nan YANG Qing State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Laboratory of Human Evolution and Archeological Science Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Graduate University of Chinese Academy of Sciences Beifing 100049 China Institute for Environmental Research the Australian Nuclear Science and Technology Organization Sydney NSW 1001 Australia

Neolithic agricultural development and environmental effects in the Longdong area were reconstructed using a synthetic approach,investigating pollen,charcoal,and seed remains for two cultural layer sections and five flotation *** show that Neolithic agriculture in the Longdong area had a simple organization and was dominated by the production of common millet,especially in the early and middle Yangshao *** the late Yangshao age,Neolithic agriculture developed into a more complex structure,dominated by both common and foxtail millet and the cultivation of rice and *** production of foxtail millet gradually increased through the Neolithic period,reaching its highest point during the Qijia *** were first cultivated during the late Yangshao culture,approximately 5000 cal a *** production began no later than 4800 cal a BP,and continued to exist in the Qijia culture,approximately 4000 cal a *** production in Neolithic Longdong,specifically in the "Yuan" area of the loess plateau,developed as a shrub and grass dominated *** in the river valleys was partly covered with Picea,Tusga,and Quercus coniferous and broadleaf mixed *** activity during the Neolithic period caused an increase in farmland on the loess tableland and a decrease in the abundance of shrub and grassland in the Longdong *** farmlands were abandoned,vegetation recovered with Hippophae-,Rosaceae-,Ephedra-,and Leguminosae-dominated shrublands and Artemisia-dominated grasslands.

关键词：新石器时代农业发展陇东地区环境影响甘肃东部早期新石器时期盆地

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格尼襟翼在冰风洞混合翼设计中的应用

航空学报 2019年第2期40卷 74-79页

作者：韩志熔赵克良颜巍中国商飞上海飞机设计研究院上海201210

提出面向工程、面向适航的混合翼设计准则,基于此准则提出将格尼襟翼应用于民机机翼结冰风洞试验的单段混合翼设计中。设计准则中只对驻点位置和前缘吸力峰值提出保守性要求,易于工程实现,满足结冰适航要求。对于偏离设计点较大的状态,... 详细信息

提出面向工程、面向适航的混合翼设计准则,基于此准则提出将格尼襟翼应用于民机机翼结冰风洞试验的单段混合翼设计中。设计准则中只对驻点位置和前缘吸力峰值提出保守性要求,易于工程实现,满足结冰适航要求。对于偏离设计点较大的状态,在单段混合翼后缘添加格尼襟翼并配合迎角调整,使得单段混合翼在此状态点处仍满足设计准则。这样使得单段混合翼也能应用于试验状态比较广的结冰风洞试验中。格尼襟翼的使用,降低了混合翼设计、试验费用,为民机结冰试航取证节约了时间。

关键词：面向适航混合翼设计准则格尼襟翼驻点位置前缘吸力峰值

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民用飞机攻角传感器安装定位研究

空气动力学学报 2015年第3期33卷 420-426页

作者：赵克良周峰张淼南京航空航天大学江苏南京210016 上海飞机设计研究院上海201210

对民用飞机风标式攻角传感器安装定位进行了研究。根据相关条例中攻角传感器安装使用的要求,提出了侧滑敏感性分析方法和攻角校线分析方法。利用数值模拟方法对传统机头和"流线型机头+翼身组合体"构型进行气动计算,通过侧滑敏感性分析... 详细信息

对民用飞机风标式攻角传感器安装定位进行了研究。根据相关条例中攻角传感器安装使用的要求,提出了侧滑敏感性分析方法和攻角校线分析方法。利用数值模拟方法对传统机头和"流线型机头+翼身组合体"构型进行气动计算,通过侧滑敏感性分析方法和攻角校线分析方法,对攻角传感器的安装位置规律进行分析,最终在两种机头外形上得到相同的攻角传感器安装定位规律——轴向48%~100%机头最大宽度线上为攻角传感器的最佳安装位置。将得到的规律应用至构型一的攻角传感器安装定位中,并通过风洞试验对安装位置处的侧滑敏感性以及攻角校线进行验证,结果表明侧滑敏感性和攻角校线试验结果与CFD计算结果完全一致,证明了本文提出的攻角传感器安装定位分析方法合理、可行,总结的规律正确,对机头外形类似飞机的攻角传感器安装定位具有一定的参考价值。

关键词：攻角传感器 CFD 侧滑敏感性攻角校线定位

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砂纸冰对民机平尾气动特性的影响

航空学报 2024年第2期45卷 151-166页

作者：李海星周峰颜巍白峰赵克良中国商用飞机有限责任公司、上海飞机设计研究院上海201210

平尾结冰严重影响飞机的纵向操纵性及稳定性。为研究结砂纸冰对平尾气动特性的影响,采用基于某民机平尾设计的大、小模型,在低速增压风洞中开展了带砂纸冰的测力试验,分析了砂纸冰粗糙度、雷诺数、角冰粗糙度对带冰平尾气动特性的影响规... 详细信息

平尾结冰严重影响飞机的纵向操纵性及稳定性。为研究结砂纸冰对平尾气动特性的影响,采用基于某民机平尾设计的大、小模型,在低速增压风洞中开展了带砂纸冰的测力试验,分析了砂纸冰粗糙度、雷诺数、角冰粗糙度对带冰平尾气动特性的影响规律,同时总结了砂纸冰的缩比方法。结果表明:砂纸冰粗糙度增加会导致平尾气动特性逐步恶化,在飞行雷诺数条件下,当冰型粗糙度相对高度为0.2×10^(-3)~0.6×10^(-3)时,相比于无冰条件,最大升力系数降低0.3~0.4;雷诺数对带砂纸冰平尾气动特性的影响超过对带角冰平尾的影响,但远小于对干净平尾的影响,当带砂纸冰平尾雷诺数由3.29×10^(6)提高至13.1×10^(6)后,其最大升力系数提高0.02~0.04;角冰表面粗糙度的变化对平尾气动特性的影响较小,由粗糙度带来的升力损失远小于角冰本身所带来的影响;当砂纸冰高度远超过当地边界层厚度时,风洞试验可根据模型比例对砂纸冰粗糙度进行几何缩比,而当砂纸颗粒较小时,采用几何缩比方式获得的砂纸冰对平尾气动力影响相对较小。提出了基于边界层厚度的砂纸冰粗糙度缩比方法,该方法的适用性还需要进一步验证。

关键词：砂纸冰平尾风洞试验气动特性粗糙度雷诺数边界层

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民用飞机静压孔布局规律

空气动力学学报 2017年第6期35卷 823-827页

作者：周峰赵克良张淼汪君红上海飞机设计研究院上海201210

对民用飞机静压孔布局规律进行了研究。确定相关条例中静压孔的安装使用要求,将其转换成具体的设计分析技术指标;利用数值模拟方法对翼身组合体构型进行气动计算,得到不同状态下机身表面压力分布;对机身表面压力分布均方根进行分析,得... 详细信息

对民用飞机静压孔布局规律进行了研究。确定相关条例中静压孔的安装使用要求,将其转换成具体的设计分析技术指标;利用数值模拟方法对翼身组合体构型进行气动计算,得到不同状态下机身表面压力分布;对机身表面压力分布均方根进行分析,得到机身表面静压随马赫数、攻角变化较小的区域,定义为稳压线;将机身等直段等效为圆柱体,将来流分解为轴向平直流动和圆柱周向绕流,通过圆柱绕流Cp分布理论分析,获得与计算结果一致的稳压线分布规律,表明稳压线分布规律的普适性。开展高低速测压风洞试验,对稳压线规律进行验证,结果表明稳压线上压力分布变化范围趋近于0,试验结果与CFD计算结果以及理论分析结果高度一致,证明了稳压线计算及分析方法合理、可行,静压孔布局规律的正确、普适。所得稳压线分布规律可为常规布局民用飞机静压孔布局提供直接参考。

关键词：静压孔 CFDD稳压线圆柱绕流见律