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Factors contributing to the oxygen concentration over the Qinghai-Tibetan Plateau and its contribution rate calculation

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Science China Earth Sciences 2024年第2期67卷 497-509页

作者： peijun shi Ying ZHANG Yanqiang CHEN Wenquan ZHU Xiaokang HU Heyi YANG Lu JIANG Yonggui MA Haiping TANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing100875China The Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China Academy of Plateau Science and Sustainability People’s Government of Qinghai Province&Beijing Normal UniversityXining810016China

A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still lacking.Here,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan Station.Using seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration.Our results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial differences.Vegetation significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing research.Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation.To better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration.

关键词： Qinghai-Tibetan Plateau Oxygen concentration Relative contribution rate Air temperature Vegetation

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Review and prospect of soil compound erosion

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Journal of Arid Land 2023年第9期15卷 1007-1022页

作者： YANG Wenqian ZHANG Gangfeng YANG Huimin LIN Degen shi peijun State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Academy of Disaster Reduction and Emergency Management Ministry of Emergency Management and Ministry of EducationBeijing Normal UniversityBeijing 100875China College of Land and Tourism Luoyang Normal UniversityLuoyang 471934China School of Business Wenzhou UniversityWenzhou 325035China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810016China

Soil erosion is one of the most serious environmental issues constraining the sustainable development of human society and economies.Soil compound erosion is the result of the alternation or interaction between two or more erosion forces.In recent years,fluctuations and extreme changes in climatic factors(air temperature,precipitation,wind speed,etc.)have led to an increase in the intensity and extent of compound erosion,which is increasingly considered in soil erosion research.First,depending on the involvement of gravity,compound erosion process can be divided into compound erosion with and without gravity.We systematically summarized the research on the mechanisms and processes of alternating or interacting soil erosion forces(wind,water,and freeze-thaw)considering different combinations,combed the characteristics of compound erosion in three typical regions,namely,high-elevation areas,high-latitude areas,and dry and wet transition regions,and reviewed soil compound erosion research methods,such as station observations,simulation experiments,prediction models,and artificial neural networks.The soil erosion model of wind,water,and freeze-thaw interaction is the most significant method for quantifying and predicting compound erosion.Furthermore,it is proposed that there are several issues such as unclear internal mechanisms,lack of comprehensive prediction models,and insufficient scale conversion methods in soil compound erosion research.It is also suggested that future soil compound erosion mechanism research should prioritize the coupling of compound erosion forces and climate change.

关键词： soil compound erosion soil erosion gravity erosion wind and water erosion freeze-thaw erosion

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Monitoring rock desert formation caused by two different origins(ice-snow melting and drying)in the Qinghai-Tibet Plateau of China by considering topographic and meteorological elements

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Journal of Arid Land 2022年第8期14卷 849-866页

作者： JIA Wei shi peijun WANG Jing'ai MA Weidong XIA Xingsheng ZHOU Yuantao Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal UniversityXining 810008China School of Geographical Sciences Qinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810008China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China

Monitoring rock desert formation caused by two different origins(ice-snow melting and drying)through remote sensing is crucial to our understanding of the interaction between the underlying surface of different rock desert and land-atmosphere types,as well as the relationship between bare land and soil erosion.A number of achievements have been made in remote sensing monitoring of desert areas,but there is a lack of accurate classification and remote sensing identification of rock desert types based on formation mechanism.In this study,the north and south sides of the eastern Kunlun Mountains in the northern part of the Qinghai-Tibet Plateau of China were taken as the study areas.Landsat operational landscape imager,digital elevation model,and precipitation and temperature grid data were used as data sources.By identifying the bare areas based on the normalized difference vegetation index(NDVI),we used the multi-element fusion method of contours,isotherms,and isohyets to identify the rock desert types in the ice-snow melting and dry areas.The results showed that:(1)the rock desert areas identified by remote sensing based on topographic and meteorological elements were highly accurate,with an overall accuracy of 88.45%and kappa coefficient of 0.77.The multi-element fusion method of contours,isotherms,and isohyets could effectively identify the rock desert types in the ice-snow melting and dry areas;(2)the optimal segmentation range of the ice-snow melting and dry areas was 3600 m contour,-2°C-2°C isotherms,and 100-130 mm isohyets.The areas with elevation less than 3600 m,annual average temperature higher than 2°C,and average annual precipitation less than 100 mm were rock desert in the dry areas.The range of-2°C-2°C isotherms and 100-130 mm isohyets was the transition area between the ice-snow melting and dry areas.The areas with elevation higher than 3600 m,annual average temperature less than-2°C,and average annual precipitation higher than 130 mm were rock desert in the ice-snow melting areas;and(3)the identifi

关键词： rock desert in the ice-snow melting areas rock desert in the dry areas contours isotherms isohyets Qinghai-Tibet Plateau

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Modeling the impacts of drying trend scenarios on land systems in northern China using an integrated SD and CA model

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Science China Earth Sciences 2014年第4期57卷 839-854页

作者： HUANG QingXu HE ChunYang LIU ZhiFeng shi peijun State Key Laboratory of Earth Surface Processes and Resource Ecology (Beijing Normal University)

Climate-induced drought has exerted obvious impacts on land systems in northern China.Although recent reports by the Intergovernmental Panel on Climate Change(IPCC) have suggested a high possibility of climate-induced drought in northern China,the potential impacts of such drying trends on land systems are still unclear.Land use models are powerful tools for assessing the impacts of future climate change.In this study,we first developed a land use scenario dynamic model(iLUSD) by integrating system dynamics and cellular automata.Then,we designed three drying trend scenarios(reversed drying trend,gradual drying trend,and acceleration of drying trend) for the next 25 years based on the IPCC emission scenarios and considering regional climatic predictions in northern China.Finally,the impacts of drying trend scenarios on the land system were simulated and compared.An accuracy assessment with historic data covering 2000 to 2005 indicated that the developed model is competent and reliable for understanding complex changes in the land use system.The results showed that water resources varied from 441.64 to 330.71 billion m3 among different drying trend scenarios,suggesting that future drying trends will have a significant influence on water resource and socioeconomic development.Under the pressures of climate change,water scarcity,and socioeconomic development,the ecotone(i.e.,transition zone between cropping area and nomadic area) in northern China will become increasingly vulnerable and hotspots for land-use change.Urban land and grassland would have the most prominent response to the drying trends.Urban land will expand around major metropolitan areas and the conflict between urban and cultivated land will become more severe.The results also show that previous ecological control measures adopted by the government in these areas will play an important role in rehabilitating the environment.In order to achieve a sustainable development in northern China,issues need to be addressed such as how to arrange land use struc

关键词：干旱化趋势中国北方土地系统 CA模型模拟未来气候变化土地利用系统社会经济发展

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宋朝的动物书写——以苏轼诗文所见为中心

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社会科学战线 2024年第6期 178-189页

作者：刁培俊厦门大学历史与文化遗产学院福建厦门361005

苏轼宦游一生,所历之地覆盖了北宋的大部分版图,其经历之广,观察之细,阅读之繁,描述之多,非庸常儒士能比。在他的作品中出现了数量众多、种类不一的动物,构成了苏轼视域下实在与意象的生物世界。其中“被书写”的有软体和节肢动物门的... 详细信息

苏轼宦游一生,所历之地覆盖了北宋的大部分版图,其经历之广,观察之细,阅读之繁,描述之多,非庸常儒士能比。在他的作品中出现了数量众多、种类不一的动物,构成了苏轼视域下实在与意象的生物世界。其中“被书写”的有软体和节肢动物门的鳆鱼、蛤蜊、红螺,虾、蟹、蚊、蛩、蜂、蝶、蝗虫等;鱼纲则有鲂鱼、鲤鱼、鲈鱼、鳊鱼、鳜鱼、鲟鱼、鲫鱼、河豚、■鱼、子鱼、白鱼、沙鱼等;爬行纲的有蛇、壁虎、鼍、龟、玳瑁;鸟纲动物有鸡、雁、鹤、鹰、隼、鸥、鹭、燕、鹘、鹌鹑、鸬鹚、鹈鹕、■鸟、白鹇、鸺鹠、斑鸠、快活鸟、提壶鸟、五色雀、桐花鸟等;属于兽类(哺乳纲)的有牛、羊、马、猪、狗、鼠、虎、猿、狨、狐、鹿、麋、犀、獐、蝙蝠、鼯鼠、竹■、牛尾狸等。文章通过苏轼的存世文本再现这一历史景观并对其进行解读,由此反思方法论意义上“历史上的动物转向”和“动物的自然史”。

关键词：苏轼动物写实意象动物的自然史

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An experimental study on the influences of water erosion on wind erosion in arid and semi-arid regions

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Journal of Arid Land 2019年第2期11卷 208-216页

作者： YANG Huimin ZOU Xueyong WANG Jing'ai shi peijun State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University School of Land and Tourism Luoyang Normal University Key Laboratory of Regional Geography Beijing Normal University Faculty of Geographical Science Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Beijing Normal University Academy of Disaster Reduction and Emergency Management Beijing Normal University

Complex erosion by wind and water causes serious harm in arid and semi-arid regions. The interaction mechanisms between water erosion and wind erosion is the key to further our understanding of the complex erosion. Therefore, in-depth understandings of the influences of water erosion on wind erosion is needed. This research used a wind tunnel and two rainfall simulators to investigate the influences of water erosion on succeeding wind erosion. The wind erosion measurements before and after water erosion were run on semi-fixed aeolian sandy soil configured with three slopes(5°, 10° and 15°), six wind speeds(0, 9, 11, 13, 15 and 20 m/s), and five rainfall intensities(0, 30, 45, 60 and 75 mm/h). Results showed that water erosion generally restrained the succeeding wind erosion. At a same slope, the restraining effects decreased as rainfall intensity increased, which decreased from 70.63% to 50.20% with rainfall intensity increased from 30 to 75 mm/h. Rills shaped by water erosion could weaken the restraining effects at wind speed exceeding 15 m/s mainly by cutting through the fine grain layer, exposing the sand layer prone to wind erosion to airflow. In addition, the restraining effects varied greatly among different soil types. The restraining effects of rainfall on the succeeding wind erosion depend on the formation of a coarsening layer with a crust and a compact fine grain layer after rainfall. The findings can deepen the understanding of the complex erosion and provide scientific basis for regional soil and water conservation in arid and semi-arid regions.

关键词： wind erosion water erosion sandy soil particle size surface roughness wind-water erosion agriculturalpastoral ecotone

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Quantifying social vulnerability for flood disasters of insurance company

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Journal of Southeast University(English Edition) 2008年第S1期24卷 147-150页

作者： Ge, Yi Liu, Jing Li, Fengying shi, peijun State Key Laboratory of Pollution Control and Resource Reuse Nanjing University Nanjing 210093 China Key Laboratory of Environment Change and Natural Disaster Beijing Normal University Beijing 100875 China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China

Social vulnerability assessments are largely ignored when compared with biophysical vulnerability assessments. This is mainly due to the fact that there are more difficulties in quantifying them. Aiming at several pitfalls still existing in the Hoovering approach which is widely accepted, a suitable modified model is provided. In this modified model, the integrated vulnerability is made an analogy to the elasticity coefficient of a spring, and an objective evaluation criterion is established. With the evaluation criterion, the assessment indicators of social vulnerability are filtered and their weight assignments are accomplished. There is an application in the city of Changsha where floods occur often. With the relative data from the PICC Hunan Province Branch, a generalized regression neural network model is established in Matlab 7.0 and used to evaluate a company's flood social vulnerability index (SoVI). The results show that the average flood social vulnerability in Yuhua district is the highest, while Yuelu district is the lowest. It is good for disaster risk management and decision-making of insurance companies.

关键词： social vulnerability index flood insurance generalized regression neural network (GRNN)

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An experimental study on the influences of wind erosion on water erosion

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Journal of Arid Land 2017年第4期9卷 580-590页

作者： YANG Huimin GAO Yuan LIN Degen ZOU Xueyong WANG Jing'ai shi peijun State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Key Laboratory of Regional Geography Beijing Normal UniversityBeijing 100875China School of Geography Beijing Normal UniversityBeijing 100875China College of Life Science&Technology Hebei Normal University of Science&TechnologyQinhuangdao 066000China Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Beijing Normal UniversityBeijmg 100875China Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875China

In semi-arid regions, complex erosion resulted from a combination of wind and water actions has led to a massive soil loss and a comprehensive understanding of its mechanism is the first step toward prevention of the erosion. However, the mutual influences between wind erosion and water erosion have not been fully understood. This research used a wind tunnel and two rainfall simulators and simulated two rounds of alternations between wind erosion and water erosion（i.e., 1^（st） wind erosion–1^（st） water erosion and 2^（nd） wind erosion–2^（nd） water erosion） on three slopes（5°, 10°, and 15°） with six wind speeds（0, 9, 11, 13, 15, and 20 m/s） and five rainfall intensities（0, 30, 45, 60, and 75 mm/h）. The objective was to analyze the influences of wind erosion on succeeding water erosion. Results showed that the effects of wind erosion on water erosion were not the same in the two rounds of tests. In the 1^（st） round of tests, wind erosion first restrained and then intensified water erosion mostly because the blocking effect of wind-sculpted micro-topography on surface flow was weakened with the increase in slope. In the 2^（nd） round of tests, wind erosion intensified water erosion on beds with no rills at gentle slopes and low rainfall intensities or with large-size rills at steep slopes and high rainfall intensities. Wind erosion restrained water erosion on beds with small rills at moderate slopes and moderate rainfall intensities. The effects were mainly related to the fine grain layer, rills and slope of the original bed in the 2^（nd） round of tests. The findings can deepen our understanding of complex erosion resulted from a combination of wind and water actions and provide scientific references to regional soil and water conservation.

关键词： wind-water interaction sandy soil particle size surface roughness wind and water erosion

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Correlation analysis of Normalized Different Vegetation Index(NDVI)difference series and climate variables in the Xilingole steppe,China from 1983 to 1999

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Frontiers in Biology 2007年第2期2卷 218-228页

作者： GU Zhihui CHEN Jin shi peijun XU Ming School of Architecture and Urban Planning Shenzhen UniversityShenzhen 518060China Key Laboratory of Environmental Change and Nature Disaster Ministry of Education of ChinaCollege of Resource Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Ecology Evolution and Natural ResourcesRutgers UniversityNew BrunswickNJ 08901-8551USA

There is a crucial need in the study of global change to understand how terrestrial ecosystems respond to the climate system.It has been demonstrated by many researches that Normalized Different Vegetation Index(NDVI)time series from remotely sensed data,which provide effective information of vegetation conditions on a large scale with highly temporal resolution,have a good relation with meteorological factors.However,few of these studies have taken the cumulative property of NDVI time series into account.In this study,NDVI difference series were proposed to replace the original NDVI time series with NDVI difference series to reappraise the relationship between NDVI and meteorological factors.As a proxy of the vegetation growing process,NDVI difference represents net primary productivity of vegetation at a certain time interval under an environment controlled by certain climatic conditions and other factors.This data replacement is helpful to eliminate the cumulative effect that exist in original NDVI time series,and thus is more appropriate to understand how climate system affects vegetation growth in a short time scale.By using the correlation analysis method,we studied the relationship between NOAA/AVHRR ten-day NDVI difference series and corresponding meteorological data from 1983 to 1999 from 11 meteorological stations located in the Xilingole steppe in Inner Mongolia.The results show that:(1)meteorological factors are found to be more significantly correlation with NDVI difference at the biomass-rising phase than that at the falling phase;(2)the relationship between NDVI difference and climate variables varies with vegetation types and vegetation communities.In a typical steppe dominated by Leymus chinensis,temperature has higher correlation with NDVI difference than precipitation does,and in a typical steppe dominated by Stipa krylovii,the correlation between temperature and NDVI difference is lower than that between precipitation and NDVI difference.In a typical steppe dominated by Stipa grandis,there is

关键词： Normalized Different Vegetation Index(NDVI)difference series autocorrelation and non-stationarity correlation analysis precipitation and temperature

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Climate change regionalization in China(1961–2010)

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Science China Earth Sciences 2014年第11期57卷 2676-2689页

作者： shi peijun SUN Shao WANG Ming LI Ning WANG JingAi JIN YunYun GU XiaoTian YIN WeiXia State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Beijing Normal University Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education School of Geography Beijing Normal University Key Laboratory of Regional Geography Beijing Normal University

Since climatic condition is the important foundation for human subsistence and development and the key factor in sustainable development of economy and society, climate change has been a global issue attracting great attentions of politicians, scientists, governments, and the public alike throughout the world. Existing climate regionalization in China aims to characterize the regional differences in climate based on years of the mean value of different climate indexes. However, with the accelerating climate change nowadays, existing climate regionalization cannot represent the regional difference of climate change, nor can it reflect the disasters and environmental risks incurred from climate changes. This paper utilizes the tendency value and fluctuation value of temperature and precipitation from 1961 to 2010 to identify the climate change quantitatively, and completes the climate change regionalization in China(1961–2010) with county administrative regionalization as the unit in combination with China's terrain feature. Level-I regionalization divides China's climate change(1961–2010) into five tendency zones based on the tendency of temperature and precipitation, which are respectively Northeast China-North China warm-dry trend zone, East China-Central China wet-warm trend zone, Southwest China-South China dry-warm trend zone, Southeast Tibet-Southwest China wet-warm trend zone, and Northwest China-Qinghai-Tibet Plateau warm-wet trend zone; level-II regionalization refers to fourteen fluctuation regions based on level-I regionalization according to the fluctuation of temperature and precipitation.

关键词：气候变化中国北方区域化中国西南地区社会可持续发展气候区划中国西北地区人类生存

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