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Volume fractal dimension of soil particles and relationships with soil physical-chemical properties and plant species diversity in an alpine grassland under different disturbance degrees

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Journal of Arid Land 2013年第4期5卷 480-487页

作者： YanYan LIU yanming gong Xin WANG YuKun HU Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Xinjiang Branch of Chinese Academy of Sciences

Fractal geometry is an important method in soil science,and many studies have used fractal theory to examine soil properties and the relationships with other eco-environmental factors.However,there have been few studies examining soil particle volume fractal dimension in alpine grasslands.To study the volume fractal dimension of soil particles （D） and its relationships with soil salt,soil nutrient and plant species diversity,we conducted an experiment on an alpine grassland under different disturbance degrees：non-disturbance （N0）,light disturbance （L）,moderate disturbance （M） and heavy disturbance （H）.The results showed that （1） Ds varied from 2.573 to 2.635 among the different disturbance degrees and increased with increasing degrees of disturbance.（2） Shannon-Wiener diversity index,Pielou＇s evenness index and Margalef richness index reached their highest values at the M degree,indicating that moderate disturbance is beneficial to the increase of plant species diversity.（3） In the L and M degrees,there was a significant positive correlation between D and clay content and a significant negative correlation between D and soil organic matter （SOM）.In the H degree,D was significantly and positively correlated with total salt （TS）.The results suggested that to a certain extent,D can be used to characterize the uniformity of soil texture in addition to soil fertility characteristics.（4） For the L degree,there was a significant negative correlation between D and the Shannon-Wiener diversity index; while for the M degree,there was a significant negative correlation between D and Pielou＇s evenness index.

关键词： alpine grassland disturbance degree volume fractal dimension of soil particles species diversity

Fluxes of methane,carbon dioxide and nitrous oxide in an alpine wetland and an alpine grassland of the Tianshan Mountains,China

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Journal of Arid Land 2014年第6期6卷 717-724页

作者： GuiXiang HE KaiHui LI XueJun LIU yanming gong YuKun HU Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences College of Resources and Environmental Sciences China Agricultural University

Methane （OH4）, carbon dioxide （CO2） and nitrous oxide （N2O） are known to be major greenhouse gases that contribute to global warming. To identify the flux dynamics of these greenhouse gases is, therefore, of great significance. In this paper, we conducted a comparative study on an alpine grassland and alpine wetland at the Bayinbuluk Grassland Eco-system Research Station, Chinese Academy of Sciences. By using opaque, static, manual stainless steel chambers and gas chromatography, we measured the fluxes of CH4, N2O and CO2 from the grassland and wetland through an in situ monitoring study from May 2010 to October 2012. The mean flux rates of CH4, N2O and CO2 for the experimental alpine wetland in the growing season （from May to October） were estimated at 322.4 μg/（m2.h）, 16.7 μg/（m2.h） and 76.7 mg/（m2.h）, respectively; and the values for the alpine grassland were -88.2 μg/（m2.h）, 12.7 μg/（m2.h）, 57.3 mg/（m2.h）, respectively. The gas fluxes showed large seasonal and annual variations, suggesting weak fluxes in the non-growing season. The relationships between these gas fluxes and environmental factors were analyzed for the two alpine ecosystems. The results showed that air temperature, precipitation, soil temperature and soil moisture can greatly influence the fluxes of CH4, N2O and CO2, but the alpine grassland and alpine wetland showed different feedback mechanisms under the same climate and environmental conditions.

关键词： alpine wetland alpine grassland CH4 N2O CO2 Tianshan Mountains

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宋代帝后、内外命妇、宫人女官官衔研究

中原文化研究 2024年第2期12卷 75-84页

作者：龚延明殷其雷浙江大学人文学院古籍研究所暨宋学研究中心浙江杭州310028 浙江大学宋学研究中心《宋学研究》编辑部浙江杭州310028

宋代官衔,是目前宋代制度史研究中新开拓的领域。从宋代帝后、内外命妇、宫人女官的官衔制度这一视角,可以看出宋代官制的复杂性、多样性。皇帝,通常不视为官,实际某种意义上,皇帝也是官,且居于官僚机构的顶端,所以皇帝也有官衔,只是名... 详细信息

宋代官衔,是目前宋代制度史研究中新开拓的领域。从宋代帝后、内外命妇、宫人女官的官衔制度这一视角,可以看出宋代官制的复杂性、多样性。皇帝,通常不视为官,实际某种意义上,皇帝也是官,且居于官僚机构的顶端,所以皇帝也有官衔,只是名号比较特殊,显示其至高无上的地位。“皇帝”本身就是一个官号,其生前有尊号或圣号,死后有谥号、庙号。唐宋史称皇帝多用庙号,这就是法定官衔。皇后有官号,尊号有无,视其是否曾垂帘听政而定,死后谥号有二字、四字之别。内命妇,为皇帝姬妾名号之总称,其官衔有等级之分、秩品之差。外命妇官衔可分为公主官衔、卿大夫妻母官衔两类。内外命妇官衔亦特旨移用于宫人女官官衔。皇后、内外命妇、宫人女官的官衔,与文武百官相类,其名号等级分明,官衔成为其特殊身份的标志。

关键词：宋代官衔帝后内外命妇宫人女官

Dependency of litter decomposition on litter quality,climate change,and grassland type in the alpine grassland of Tianshan Mountains,Northwest China

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Journal of Arid Land 2022年第6期14卷 691-703页

作者： SU Yuan gong yanming HAN Wenxuan LI Kaihui LIU Xuejun College of Grassland Science Shanxi Agricultural UniversityTaigu 030801China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China

Litter decomposition is an important component of the nutrient recycling process and is highly sensitive to climate change.However,the impacts of warming and increased precipitation on litter decomposition have not been well studied,especially in the alpine grassland of Tianshan Mountains.We conducted a manipulative warming and increased precipitation experiment combined with different grassland types to examine the impact of litter quality and climate change on the litter decomposition rate based on three dominant species(Astragalus mongholicus,Potentilla anserina,and Festuca ovina)in Tianshan Mountains from 2019 to 2021.The results of this study indicated there were significant differences in litter quality,specific leaf area,and leaf dry matter content.In addition,litter quality exerted significant effects on litter decomposition,and the litter decomposition rate varied in different grassland types.Increased precipitation significantly accelerated the litter decomposition of P.anserina;however,it had no significant effect on the litter decomposition of A.mongholicus and F.ovina.However,warming consistently decreased the litter decomposition rate,with the strongest impact on the litter decomposition of F.ovina.There was a significant interaction between increased precipitation and litter type,but there was no significant interaction between warming and litter type.These results indicated that warming and increased precipitation significantly influenced litter decomposition;however,the strength was dependent on litter quality.In addition,soil water content played a crucial role in regulating litter decomposition in different grassland types.Moreover,we found that the litter decomposition rate exhibited a hump-shaped or linear response to the increase of soil water content.Our study emphasizes that ongoing climate change significantly altered litter decomposition in the alpine grassland,which is of great significance for understanding the nutrient supply and turnover of litter.

关键词： litter decomposition rate litter quality warming increased precipitation grassland type Tianshan Mountains

高寒草地土壤掩埋对凋落物分解速率的影响大于氮素富集

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Journal of Plant Ecology 2021年第6期14卷 1047-1059页

作者： Yuan Su Jiajia Le Xiaofei Ma Xiaolong Zhou Yunxin Zhang yanming gong Wenxuan Han Kaihui Li Xuejun Liu State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Bayinbuluk Grassland Ecosystem Research Station Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesBayinbuluk 841314China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Research Center for Ecology and Environment of Central Asia Urumqi 830011China Key Laboratory of Oasis Ecology Xinjiang UniversityUrumqi 830046XinjiangChina Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

由于高寒草地退化、鼠害严重、大风频繁等原因,凋落物被频繁掩埋在土壤中。但凋落物的位置变化和氮富集对高寒草原凋落物分解速率和养分动态影响的认识尚不清楚。为了研究凋落物位置变化(地表、掩埋10 cm和悬空60 cm)和氮富集对高寒草... 详细信息

由于高寒草地退化、鼠害严重、大风频繁等原因,凋落物被频繁掩埋在土壤中。但凋落物的位置变化和氮富集对高寒草原凋落物分解速率和养分动态影响的认识尚不清楚。为了研究凋落物位置变化(地表、掩埋10 cm和悬空60 cm)和氮富集对高寒草原优势植物凋落物分解的影响,本研究依托2009年在新疆天山巴音布鲁克高寒草原设置的长期模拟氮沉降研究平台,以对照和氮富集处理样方的优势植物羊茅(Festuca ovina)和赖草(Leymus tianschanicus)凋落物为试验材料,测定分解过程中凋落物质量损失和碳氮磷含量的变化特征。研究结果表明,掩埋凋落物分解速率显著快于地表凋落物,悬空处理凋落物分解速率慢于地表凋落物。氮富集显著影响凋落物质量,进而影响凋落物分解。而凋落物质量残留在对照与氮富集土壤掩埋之间无显著差异。这些结果表明,氮富集通过凋落物质量而不是通过土壤环境因素,影响短期凋落物分解。不同处理的所有试验凋落物均有碳和磷的释放现象。对照处理的凋落物,凋落物氮以累积为主,而氮富集处理的凋落物,凋落物氮以释放为主。这表明凋落物分解可能受到氮元素限制,氮富集改变了凋落物分解调控的氮循环过程。本研究提供了直接证据,掩埋处理的凋落物有更快的质量损失和碳元素释放,土壤掩埋是旱地凋落物分解速率比模型预测的快的一个候选解释。

关键词：高寒草地氮富集凋落物位置凋落物分解凋落物质量养分释放

Exciting broadband thermochromic transmission property opposite to vanadium dioxide in the atmospheric window

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Science China Technological Sciences 2024年第7期67卷 2244-2254页

作者： gong YiQuan GUO yanming CHEN ShuNi LI Meng PAN QingHui SHUAI Yong Ministry of Industry and Information Technology Key Laboratory of Aerospace Thermophysics School of Energy Science and EngineeringHarbin Institute of Technology

The traditional telecommunications band performs poorly in harsh weather conditions due to atmospheric absorption. In recent years, researchers have begun to study optical communication through atmospheric windows, and optical switches are an essential component of optical communication. A broadband atmospheric window optical switch was proposed based on Vanadium dioxide and magnetic polaritons(MP). It is formed by the stacking of two metal-dielectric-metal structures. The simulation results show that the modulation depth can reach 98.38%, and the extinction ratio is 17.93 dB. By calculating the magnetic field, we confirmed that the reason for the “off” mode is the coupling between the different MP modes, while the “on”mode is the excitation of MP. The optical switch we proposed may be applied to radiation cooling and optical satellite communication.

关键词： optical communication thermochromic property atmospheric window optical switch magnetic polariton

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宋代官品與品官制度

中华文史论丛 2022年第2期 101-154,398,399页

作者：龔延明浙江大學古籍研究所暨宋學研究中心

本文將官品與品官結合起來探討,從一個新的視角,嘗試研究宋代官品。官品是一個抽象的等級符號,流内一命之官即獲官品;有品之官,即爲品官。兩者相互聯繫不可分割。官品在宋代經歷了從九品正從三十階到九品正從十八階的變化。官品本身没... 详细信息

本文將官品與品官結合起來探討,從一個新的視角,嘗試研究宋代官品。官品是一個抽象的等級符號,流内一命之官即獲官品;有品之官,即爲品官。兩者相互聯繫不可分割。官品在宋代經歷了從九品正從三十階到九品正從十八階的變化。官品本身没有實際意義,必須通過品官的各種載體,其“尺規”作用纔能得到體現。宋代官品的載體有文武散官、職事官、職名、本官、寄禄官、勳、爵、内外命婦、内侍官等等。凡命官身分,必須通過其所繫官銜的官品,得到條法確認。宋代官品的多元職能,就在於它是表示品官官銜中各種不同官稱的“尺規”。官品不同,代表着命官相應的位遇之不同。諸如官品通過散官階、職事官、勳、爵、職名、寄禄官、章服等定位,決定品官的高下尊卑、俸禄位遇,從而決定品官官户、非官户,親屬蔭官、贈官,品官贖刑等等社會地位與依法可享受的待遇。官品與品官之影響,波及吏胥、庶民,至於黄冠道流,也以官品爲等。官品在宋代政治、社會生活中具有重要意義,是無可置疑的。

关键词：宋代官品品官官本位

Plant diversity-productivity patterns in the alpine steppe environment of the Central Tianshan Mountains

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Journal of Arid Land 2009年第1期1卷 43-48页

作者： Hu, YuKun Li, KaiHui gong, yanming Yin, Wei Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China

The biodiversity-productivity relationship is an important topic in the research of biodiversity and ecosystem function. The plant diversity productivity pattern is commonly unimodal and positively correlated. This paper researches the characteristics of plant diversity-productivity patterns in the Bayanbuluk alpine steppe in the central Tianshan Mountains, Xinjiang, China, and analyzes the effects of environmental factors on the distribution of plant communities, species composition, plant diversity and productivity in the steppe. The results show a positive correlation between plant diversity and productivity. DCCA (detrended canonical correspondence analysis) ordination reveals a significant relationship between the effects of air temperature, soil moisture content, available soil nitrogen, relative humidity and pH value on the distribution and composition of plant communities. There are significant correlations between the soil moisture content, relative humidity, pH value, air temperature and species richness and the aboveground biomass of Gramineae and Cyperaceae, and also significant correlations between the relative humidity, pH values and the total aboveground biomass of plant communities.

关键词： Tianshan Mountains plant diversity productivity DCCA ordination alpine steppe environmental factor

Contrasting effects of nitrogen addition on litter decomposition in forests and grasslands in China

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Journal of Arid Land 2021年第7期13卷 717-729页

作者： SU Yuan MA Xiaofei gong yanming LI Kaihui HAN Wenxuan LIU Xuejun State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Bayanbulak Grassland Ecosystem Research Station Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesBayanbulak 841314China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Research Center for Ecology and Environment of Central Asia Urumqi 830011China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Nitrogen(N)addition has profound impacts on litter-mediated nutrient cycling.Numerous studies have reported different effects of N addition on litter decomposition,exhibiting positive,negative,or neutral effects.Previous meta-analysis of litter decomposition under N addition was mainly based on a small number of samples to allow comparisons among ecosystem types.This study presents the results of a meta-analysis incorporating data from 53 published studies(including 617 observations)across forests,grasslands,wetlands,and croplands in China,to investigate how environmental and experimental factors impact the effects of N addition on litter decomposition.Averaged across all of the studies,N addition significantly slows litter decomposition by 7.02%.Considering ecosystem types,N addition significantly accelerates litter decomposition by 3.70%and 11.22%in grasslands and wetlands,respectively,clearly inhibits litter decomposition by 14.53%in forests,and has no significant effects on litter decomposition in croplands.Regarding the accelerated litter decomposition rate in grasslands due to N addition,litter decomposition rate increases slightly with increasing rates of N addition.However,N addition slows litter decomposition in forests,but litter decomposition is at a significantly increasing rate with increasing amounts of N addition.The responses of litter decomposition to N addition are also influenced by the forms of N addition,experiential duration of N addition,humidity index,litter quality,and soil pH.In summary,N addition alters litter decomposition rate,but the direction and magnitude of the response are affected by the forms of N addition,the rate of N addition,ambient N deposition,experimental duration,and climate factors.Our study highlights the contrasting effects of N addition on litter decomposition in forests and grasslands.This finding could be used in biogeochemical models to better evaluate ecosystem carbon cycling under increasing N deposition due to the differential responses of litter decomposition

关键词： litter decomposition rate N addition ambient N deposition litter quality meta-analysis forests grasslands