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Environmental significance exploration to Tamarix ConeAge Layer in Lop Nur Lake region

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Science Bulletin 2005年第20期 141-143页

作者： xia xuncheng1, ZHAO Yuanjie2,1, WANG Fubao3. & CAO Qiongying3. 1. Xinjiang institute of {3. and {3., Chinese Academy of Sciences, urumqi 83.011, china 2. College of Resources and Environmental Sciences, Hebei Normal University, Shijiazhuang 050016, china 3. Department of Urban and Resources Sciences, Nanjing University, Nanjing 210093. china

Climate and environment reconstruction during the Medieval Warm Period in Lop Nur of Xinjiang, china

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Chinese Science Bulletin 2008年第19期53卷 3016-3027页

作者： MA ChunMei WANG FuBao CAO QiongYing xia xuncheng LI ShengFeng Li XuSheng School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China Xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China

We made multi-proxy analysis of 14C, grain size, microfossils, plant seeds, and geochemical elements on samples from a profile in the central West Lake of Lop Nur. The grain size suggests relatively stable sedimentary environment around the Medieval Warm Period (MWP) with weak storm effect, which is followed by frequent strong storm events. Abundant microfossils and plant seeds in this stage indicate a warm and humid fresh to brackish lake environment. C, N, and stable elements are high in content in the sediments while Rb/Sr, Ba/Sr, and Ti/Sr are in a steady low level. In addition, plenty of red willows lived here prior to about 700 a B.P., indicating a favorable environmental condition. The results indicate that the environment in Lop Nur and its west bank turned to be favorable at about 2200 a B.P., where the Loulan Culture began to thrive. Then the climate and environment came to be in the good condition in the Tang and Song Dynasties, when the storm effect became weaker, rainfall increased and the salty lake water turned to be brackish to fresh lake water. Hence, limnic biomass increased with higher species diversity.

关键词：中世纪新疆气候变化环境进化

亚热带三种林分土壤酶活性和酶化学计量比特征

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应用生态学报 2024年第6期35卷 1501-1508页

作者：韩子琛郭强夏允杨柳明范跃新杨玉盛福建师范大学地理科学学院/碳中和未来技术学院福州350007 福建师范大学湿润亚热带生态地理过程教育部重点实验室/福建省植物生理生态重点实验室福州350007 福建师范大学地理研究所福州350007

本研究依托同质园观测样地,选择次生林(主要树种为米槠)、10年生的米槠人工林和杉木人工林为研究对象,分析亚热带不同林分土壤酶活性和计量比特征的差异及其影响因素。结果表明:与次生林相比,米槠人工林土壤有机碳、总氮和可溶性有机碳... 详细信息

本研究依托同质园观测样地,选择次生林(主要树种为米槠)、10年生的米槠人工林和杉木人工林为研究对象,分析亚热带不同林分土壤酶活性和计量比特征的差异及其影响因素。结果表明:与次生林相比,米槠人工林土壤有机碳、总氮和可溶性有机碳含量分别显著降低42.6%、47.4%和60.9%,杉木人工林显著降低了42.9%、3..7%和61.1%。相比于次生林,米槠人工林土壤微生物生物量碳、微生物生物量氮(MBN)以及微生物生物量磷分别显著降低40.6%、3..5%和45.9%,杉木人工林显著降低了53.7%、56.4%和61.7%。与次生林相比,米槠人工林土壤酶活性变化不显著,但杉木人工林的碳获取酶(β-1,4-葡萄糖苷酶和纤维二糖水解酶)活性显著降低51.2%和59.8%,氮和磷获取酶活性分别显著降低41.0%和29.8%,碳获取酶/氮获取酶以及碳获取酶/磷获取酶分别显著降低11.3.和7.7%。冗余分析表明,MBN和硝态氮是驱动土壤酶活性及酶化学计量比变化的主要因素。不同林分的土壤酶活性和微生物养分需求存在显著差异,与次生林相比,营造杉木人工林会刺激植物与微生物的养分竞争,加剧微生物的氮、磷养分限制。

关键词：土壤胞外酶亚热带地区养分限制土壤微生物

Some Latest Achievements in Research on Environment and its Evolution in Lop Nur Region

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Science Foundation in china 2005年第2期13卷 18-24页

作者： xia xuncheng Zhao Yuanjie Xinjiang institute of ecology and geography CAS Urumqi 830011 College of Resources and Environmental Sciences Hebei Normal University Shijiazhuang 050016

Lop Nur and its near region have been given attention again with implement of the Western Development Strategy of china by the united endeavors of concerned scientific researchers. Some latest achievements have been obtained in aspects of environment and its evolution in Lop Nut and its near region in recent years. In this paper, we briefly review some latest progresses.

关键词： Lop Nur lake environmental research achievement

A preliminary study of chronology for a newly-discovered ancient city and five archaeological sites in Lop Nor, china

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Chinese Science Bulletin 2010年第1期55卷 63-71页

作者： LU HouYuan xia xuncheng LIU JiaQi QIN xiaoGuang WANG FuBao YIDILISI Abuduresule ZHOU Li Ping MU GuiJin JIAO YingXin LI JingZhi Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China School of Geographic and Oceanographic Sciences of Nanjing University Nanjing 210093 China Xinjiang Archaeological Research institute Urumqi 830000 China Laboratory for Earth Surface Processes Department of Geography Peking University Beijing 100871 China Museum of Luolan Relic Ruoqiang 841800 China The Center of Popularization and Propaganda for Science Exploration Beijing 100029 China

In the past century, it has long been debated in the archeological, historical, geographical, and many other related communities where the capital of the Luolan and Shanshan states was in the Lop Nor region. This paper presents three AMS radiocarbon ages from a newly-discovered ancient city at about 6.3.km to the northwest of the xiaohe Graveyard, and fifteen new radiocarbon ages from the Loulan (LA), LE, Qieerqiduke, Milan, and Tuyin sites in Lop Nor. The new investigation shows that the age of newly-discovered ancient city is at ca. 440–500 AD, belonging to the Northern Wei Dynasty (3.6–53. AD). This is about 100–3.0 years younger than Loulan (ca. 100–23. AD), LE (ca. 23.–3.0 AD), Qieerqiduke (ca. 200 AD), and Tuyin (ca. 100 AD). A wooden beam from Milan fortress is dated to ca. 3.0 AD, while the age on north wall at west gate of the fortress is younger, around 770 AD, suggesting that its construction time might be at the Tang Dynasty. According to 14C ages, cultural relic style, and the geographical location, the newly-discovered ancient city is probably attributed to "Zhubin City", as documented in the historical literature. Temporally, we name the city "ancient Zhubin River City". However, the characteristics and functions of this ancient city are largely unknown and need more detailed archaeological excavation and investigation in the future. Given its location near the ancient postal relay of Alagan on the crossroad, there is no doubt that the newly-discovered city was at an important geographical position on the Silk Road, no matter whether it was called "Zhubin City", or "Lielo City", or the capital of Loulan state–"Yuni City". Our findings provide new evidence for the temporal and spatial distribution of ancient relic sites and the development of civilization in western china, thus contributing to our understanding of the relationship between human activities and environmental change in the Lop Nor region.

关键词：考古遗址古代城市罗布泊年代中国

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磷添加对森林土壤有机碳影响的研究进展

亚热带资源与环境学报 2024年第1期19卷 9-15页

作者：许秋月何敏夏允杨柳明杨玉盛范跃新福建师范大学地理科学学院、碳中和未来技术学院福州350117 福建师范大学湿润亚热带山地生态国家重点实验室培育基地福州350117 福建师范大学地理研究所福州350117

土壤养分供应能力的变化可能会改变森林土壤碳库的源、汇功能。磷是陆地生态系统的限制性养分之一,其有效性变化可直接或间接调控土壤有机碳的周转。目前已有诸多文献探讨了磷添加对森林土壤有机碳的影响及其调控机制,但还缺乏相对系统... 详细信息

土壤养分供应能力的变化可能会改变森林土壤碳库的源、汇功能。磷是陆地生态系统的限制性养分之一,其有效性变化可直接或间接调控土壤有机碳的周转。目前已有诸多文献探讨了磷添加对森林土壤有机碳的影响及其调控机制,但还缺乏相对系统全面的总结。本研究综述了磷添加对森林土壤有机碳含量的影响,并从有机碳输入(凋落物、根系分泌物)、有机碳输出(土壤呼吸)和有机碳固存机制3.方面揭示磷添加对森林土壤有机碳的影响机制。研究发现磷添加后土壤有机碳含量呈现增加、降低和变化不显著3.结果,主要与生态系统类型、磷添加的强度、土壤碳周转过程等有关。此外,施磷持续时间较短、有机碳组分测定方法不统一以及揭示碳周转过程的手段缺失,是系统预测和评估磷添加对土壤有机碳影响的制约因素。未来应重点关注长期施磷对土壤有机碳的影响,并加强与微生物功能组学新技术的融合,同时考虑全球变化背景下氮磷交互作用对森林土壤有机碳的贡献。结果有助于深入理解和准确预测未来气候变化情景下森林土壤碳动态,为森林管理提供理论依据。

关键词：土壤有机碳组分颗粒态碳矿物结合态碳微生物残体碳根际过程

New evidence of agricultural activity and environmental change associated with the ancient Loulan kingdom,china,around 1500 years ago

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New evidence of agricultural activity and environmental chan...

The continuing shrinkage of snow cover in High Mountain Asia over the last four decades

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： xiaoguang Qin Jiaqi Liu Hongjuan Jia Houyuan Lu xuncheng xia Liping Zhou Guijin Mu Qinghai Xu Yinxin Jiao Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Xinjiang institute of ecology and geography Chinese Academy of Sciences Peking University Heibei Normal University

The ancient kingdom of Loulan on china’s Silk Road has disappeared for about 1500 *** records have documented widespread cultivation in Loulan which supported the kingdom’s prosperity for hundreds of ***,no farmland ruins have been found although the ancient Loulan city was discovered more than 100 years *** this study,remotely sensed,geomorphic and geological observations of possible farmlands in Loulan were analyzed.A wide distribution of partly preserved plots with recognizable regular and straight boundaries,the existence of crossed canals,the occurrence of a gypseous incrustation layer(GIL) overlying on the surface of farmland-like blocks,and extracted large-sized pollen grains of cultivated grass from GIL samples provide new evidence for the ancient *** observations revealed that the upper cultivated soil layer overlaid on GIL,*** horizon A,had been wind-eroded and GIL is the ruined soil horizon *** new findings point to a well-developed agriculture of the ancient Loulan kingdom. The size and distribution of the farmlands and the thickness of the GIL suggests that irrigation for cultivation in this currently exceedingly arid area had lasted for a long *** and lacustrine sediments in Loulan area deposited during the about 4 to—8 ka BP period,revealing that the wet Holocene optimum and two arid events of about 4 and 8 ka BP occurred in the westerlies-dominated northwest *** Loulan kingdom period was another wet stage when the ecological environment was the typical cultivated grass of oasis near *** insufficiency of water during the late period of the Loulan kingdom led the decline of irrigation agriculture and finally the renunciation of the kingdom.

关键词： ancient Loulan cultivation large sized pollen Lop Nur of Xinjiang paleoclimate ruined farmland

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Science Bulletin 2022年第20期67卷 2064-2068,M0003,M0004页

作者： Yupeng Li fan Sun Yaning Chen Baofu Li Gonghuan fang Weili Duan Qianqian xia State Key Laboratory of Desert and Oasis ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 10049China Akesu National Station of Observation and Research for Oasis Agro-ecosystem Akesu 843017China School of geography and Tourism Qufu Normal UniversityRizhao 276826China College of geography and Remote Sensing Sciences Xinjiang UniversityUrumqi 830046China College of Biology and geography Yili Normal UniversityYining 835000China

High Mountain Asia (HMA), known as Earth's "Third Pole" and"Asia's water tower",. is the largest glacier and snow reservoir onEarth except for the polar ice sheets (Text S1 and Fig. S1 online)。Snow is an important component of the HMA cryosphere, and itsvariability directly affects the water and energy balances in theregion [1,2] The average warming rate in the HMA region in recentdecades is approximately twofold higher than the average warm-ing rate in china and the world in the same period. The climatologyand trends of snow cover in the HMA have been investigated basedon station and satellite observations. However, these methodshave some limitations, resulting in large uncertainties or limita-tions in assessing long-term snow cover changes in the *** changes in the HMA region analyzed over a short timeseries may also lead to conclusions that are inconsistent with con-ventional assertions. Several studies of the temporal and spatialvariability of snow cover in the HMA region using short-termModerate Resolution lmaging Spectroradiometer data revealed nosignificant shrinkage in the snow cover area (SCA) [3..

关键词：随机森林青藏高原东南部结束日期敏感性分析 SCP 雪盖 SCD

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植物磷获取机制及其对全球变化的响应

植物生态学报 2023年第3期47卷 291-305页

作者：何敏许秋月夏允杨柳明范跃新杨玉盛福建师范大学地理科学学院福州350007 福建师范大学湿润亚热带山地生态国家重点实验室培育基地福建师范大学地理研究所福州350007

磷是植物生长的必需元素,而陆地生态系统普遍存在磷限制,全球变化可能会影响土壤磷循环过程,进一步加剧磷限制,探讨植物磷获取策略对科学预测生态系统生产力如何适应全球变化具有重要意义。该文通过收集和梳理相关文献,从4个方面综述植... 详细信息

磷是植物生长的必需元素,而陆地生态系统普遍存在磷限制,全球变化可能会影响土壤磷循环过程,进一步加剧磷限制,探讨植物磷获取策略对科学预测生态系统生产力如何适应全球变化具有重要意义。该文通过收集和梳理相关文献,从4个方面综述植物的磷获取机制及其对全球变化的响应:1)植物的磷饥饿响应机制;2)植物的磷获取途径和策略;3.土壤微生物对植物磷吸收的影响;4)植物磷吸收对全球变化(温度升高、氮沉降和降水变化)的响应及其机制。该综述有助于深入理解全球变化背景下植物适应低磷胁迫的机理,也可为养分资源管理实践提供理论依据。

关键词：磷循环微生物植物磷饥饿响应全球变化