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Nitrogen addition promotes soil carbon accumulation globally

Science China Life Sciences 2025年第01期 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling Zhu Chengjun Ji Biao Zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education key laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State key laboratory of Vegetation and environmental change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

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Measurement of ecological capital of Chinese terrestrial ecosystem based on remote sensing

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Science China Earth Sciences 2005年第6期48卷 786-796页

作者： PAN Yaozhong SHI Peijun ZHU Wenquan GU Xiaohe FAN Yida LI Jing key laboratory of environmental change and Natural disaster of the Ministry of Education of China Beijing Normal UniversityBeijing 100875China

The biosphere of the Earth is essential to human survival and *** services of ecosystems are critical to the functioning of the Earth’s life-support *** contribute to human welfare both directly and *** capital refers to the sum of the direct biological resources value and the indirect ecosystem services *** is necessary to estimate the ecological capital in order to bring it to the society and market economic system,and draw the social attention to ecological environment *** estimation model for eco-logical capital based on remote sensing is presented in this *** parameters in the model are quantitatively measured using NOAA/AVHRR and other ancillary data,including the land cover types,the vegetation coverage,and the vegetation net primary productivity(NPP)of ter-restrial *** on the economic parameters in previously published studies and a few original calculations,the annual ecological capital of the entire terrestrial ecosystem of China is quantitatively estimated at 6.44 trillion(10^(12))yuan(RMB),and the spatial distribution of the eco-logical capital is also *** ecological methods to ecological capital measurement are based on homogeneous plot scales,and the regional scaling is a key problem in their *** the proposed remote sensing approach,it provides a new method to ecological capital measurement completely based on observation *** can not only overcome the re-gional scaling problem easily,but also allows the ecological capital to be estimated objectively and spatial-explicitly.

关键词： terrestrial ecosystem ecological capital remote sensing quantitative measurement.

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The in situ observation of modelled sea ice drift characteristics in the Bohai Sea

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Acta Oceanologica Sinica 2019年第3期38卷 17-25页

作者： Yu Yan Wei Gu Yingjun Xu Qian Li key laboratory of environmental change and Natural disaster of Ministry of Education Faculty of Geographical Science Academy of disaster Reduction and Emergency Management Beijing Normal University

Sea ice drift is mainly controlled by ocean currents, local wind, and internal ice stress. Information on sea ice motion, especially in situ synchronous observation of an ice velocity, a current velocity, and a wind speed, is of great significance to identify ice drift characteristics. A sea ice substitute, the so-called "modelled ice", which is made by polypropylene material with a density similar to Bohai Sea ice, is used to complete a free drift experiment in the open sea. The trajectories of isolated modelled ice, currents and wind in the Bohai Sea during non-frozen and frozen periods are obtained. The results show that the currents play a major role while the wind plays a minor role in the free drift of isolated modelled ice when the wind is mild in the Bohai Sea. The modelled ice drift is significantly affected by the ocean current and wind based on the ice–current–wind relationship established by a multiple linear regression. The modelled ice velocity calculated by the multiple linear regression is close to that of the in situ observation, the magnitude of the error between the calculated and observed ice velocities is less than12.05%, and the velocity direction error is less than 6.21°. Thus, the ice velocity can be estimated based on the observed current velocity and wind speed when the in situ observed ice velocity is missing. And the modelled ice of same thickness with a smaller density is more sensitive to the current velocity and the wind speed changes. In addition, the modelled ice drift characteristics are shown to be close to those of the real sea ice, which indicates that the modelled ice can be used as a good substitute of real ice for in situ observation of the free ice drift in the open sea, which helps solve time availability, safety and logistics problems related to in situ observation on real ice.

关键词： Bohai Sea modelled ice in situ observation sea ice drift

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Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

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Journal of Integrative Plant Biology 2005年第9期47卷 1074-1083页

作者： Xiao-Bing LI Yun-Hao CHEN Hua YANG Yun-Xia ZHANG College of Resources Sciences and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education Beijing Normal University Beijing 100875 China

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that：（i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is s

关键词： color space transformation digital camera field measurement grassland vegetationfractional coverage.

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The Impact of Warm Pool SST and General Circulation on Increased Temperature over the Tibetan Plateau

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Advances in Atmospheric Sciences 2012年第2期29卷 274-284页

作者：王澄海余莲黄波 key laboratory of Arid Climate change and disaster Reduction of Gansu Province College of Atmospheric Science Lanzhou University key laboratory of Western China’s environmental Systems Ministry of EducationLanzhou University

In this paper, the possible reason of Tibetan Plateau （TP） temperature increasing was investigated. An increase in T min （minimum temperature） plays a robust role in increased TP temperature, which is strongly related to SST over the warm pool of the western Pacific Ocean, the subtropical westerly jet stream （SWJ）, and the tropical easterly upper jet stream （TEJ）, and the 200hPa zonal wind in East Asia. Composite analysis of the effects of SST, SWJ, and TEJ on pre and postabrupt changes in T a （annual temperature） and T min over the TP shows remarkable differences in SST, SWJ, and TEJ. A lag correlation between T a /T min , SST, and SWJ/TEJ shows that changes in SST occur ahead of changes in T a /T min by approximately one to three seasons. Partial correlations between T a /T min , SST, and SWJ/TEJ show that the effect of SWJ on T a /T min is more significant than the effect of SST. Furthermore, simulations with a community atmospheric model （CAM3.0） were performed, showing a remarkable increase in T a over the TP when the SST increased by 0.5 ？ C. The main increase in T a and T min in the TP can be attributed to changes in SWJ. A possible mechanism is that changes in SST force the TEJ to weaken, move south, and lead to increased SWJ and movement of SWJ northward. Finally, changes in the intensity and location of the SWJ cause an increase in T a /T min . It appears that TP warming is governed primarily by coherent TEJ and SWJ variations that act as the atmospheric bridges to remote SSTs in warmpool forcing.

关键词： TP temperature subtropical westerly jet tropical easterly jet warm pool

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Photosynthesis and biochemical responses to elevated O_3 in Plantago major and Sonchus oleraceus growing in a lowland habitat of northern China

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Journal of environmental Sciences 2017年第3期29卷 113-121页

作者： Benying Su Meihua Zhou Hong Xu Xiujie Zhang Yonggeng Li Hua Su Bao Xiang State key laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State key laboratory of Vegetation and environmental change Institute of BotanyChinese Academy of Sciences

A field experiment was carried out to compare the responses to ozone （03） in two common herbaceous plant species, Plantago major L. and Sonchus oleraceus L., by building open-top growth chambers in situ to simulate 03 stress （＋03, 85 ± 5 ppb, 9 hr/day for 30 days） in a lowland habitat in Inner Mongolia, Northern China. Responses to 03 of gas exchange, chlorophyll a fluorescence, leaf pigment content, andoxidant capability, soluble protein content, membrane lipid peroxidation and dark respiration （Rd） were analyzed. Results showed that elevated 03 exposure significantly reduced the light-saturated net photosyn- thesis （PNsat）, stomata] conductance （gs） and transpiration rate （E） in both species. Although non-significant interactive effect between species and 0s on PNsat was analyzed, the reduction in PNsat in S. oleraceus might be due primarily to the higher fraction of close PSII reaction centers and impaired activities of plant mesophyll cells as evidences by decreased maximum efficiency of PSII photochemistry after dark adapted state （Fv/Fm） and unchanged intercellular CO2 concentration （Ci）. Besides, biochemical analysis showed that S. oleraceus had lower antioxidant ability compared to P. major. As a result, S. oleraceus was damaged to the larger extent in terms of lipid peroxidation and visible O3 injury, indicating that S. oleraceus was more sensitive to O3 than P. major. Our results indicated that wild herbaceous plant species growing in a lowland habitat in sandy grassland were sensitive to O3 stress and S. oleraceus can be considered as one of the bio-indicators for high O3 concentration in semi-arid -rassland of northern China.

关键词： Biochemical analysisHerbaceous speciesGas exchangeOzoneSemi-arid grassland

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Modeling and Diagnostic Studies on the Variations of the Subtropical High over the Western Pacific from 1880 to 1999

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Advances in Atmospheric Sciences 2002年第6期19卷 1148-1152页

作者：王绍武蔡静宁慕巧珍谢志辉朱锦红龚道溢 Department of Atmospheric Sciences School of Physics Peking University Beijing 100871 key laboratory of environmental change and Natural disaster Beijing Normal University Beifing 100875

Index series of Subtropical High over the western Pacific was extended to AD 1880 by using of statistical and modeling method. Reconstructed indices by both methods show good accordance each other. Association of the ... 详细信息

关键词： subtropical high over the western Pacific modeling diagnostics

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A Time-dependent Stochastic Grassland Fire Ignition Probability Model for Hulun Buir Grassland of China

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Chinese Geographical Science 2013年第4期23卷 445-459页

作者： GUO Zhixing FANG Weihua TAN Jun SHI Xianwu Academy of disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education National Marine Hazard Mitigation Service State Oceanic Administration State key laboratory of Earth Surface Processes and Resource Ecology key laboratory of environmental change and Natural disaster Ministry of Education

Grassland fire is one of the most important disturbance factors in the natural *** paper focuses on the spatial distribution of long-term grassland fire patterns in the Hulun Buir Grassland located in the northeast of Inner Mongolia Autonomous Region in *** density or ratio of ignition can reflect the relationship between grassland fire and different ignition *** on the relationship between the density or ratio of ignition in different range of each ignition factor and grassland fire events,an ignition probability model was developed by using binary logistic regression function and its overall accuracy averaged up to 81.7%.Meanwhile it was found that daily relative humidity,daily temperature,elevation,vegetation type,distance to county-level road,distance to town are more important determinants of spatial distribution of fire *** Monte Carlo method,we developed a time-dependent stochastic ignition probability model based on the distribution of inter-annual daily relative humidity and daily *** this model,it is possible to estimate the spatial patterns of ignition probability for grassland fire,which will be helpful to the quantitative evaluation of grassland fire risk and its management in the future.

关键词： grassland fire binary logistic regression GIS spatial analysis ignition probability Monte Carlo method

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A Study of the Relationship between Air Pollutants and Inversion in the ABL over the City of Lanzhou

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Advances in Atmospheric Sciences 2011年第4期28卷 879-886页

作者：张强李宏宇 Gansu key laboratory of Arid Climatic change and Reducing disaster Key Open Laboratory of Arid Climatic Change and Disaster Reduction of CMAInstitute of Arid MeteorologyChinese Meteorological Administration Gansu Provincial Meteorological Bureau College of Atmospheric Sciences Lanzhou University

By analyzing the pollutant concentrations over the urban area and over the rural area of the city of Lanzhou, Gansu Province, China, the relationships between the daytime inversion intensity and the pollutant concentration in the atmospheric boundary layer （ABL） are studied with the consideration of wind speed and direction, potential temperature, specific humidity profiles, pollutant concentration in the ABL, the surface temperature, and global radiation on the ground. It was shown that the daytime inversion is a key factor in controlling air pollution concentration. A clear and positive feedback process between the daytime inversion intensity and the air pollutants over the city was found through the analysis of influences of climatic and environmental factors. The mechanisms by which the terrain and air pollutants affect the formation of the daytime inversion are discussed. The solar radiation as the essential energy source to maintain the inversion is analyzed, as are various out-forcing factors affecting the inversion and air pollutants. At last, a physical frame of relationships of air pollution with daytime inversion and the local and out-forcing factors over Lanzhou is built.

关键词： relationship Lanzhou City inversion pollutant out-forcing factors

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Mapping the Wind Hazard of Global Tropical Cyclones with Parametric Wind Field Models by Considering the Effects of Local Factors

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International Journal of disaster Risk Science 2018年第1期9卷 86-99页

作者： Chenyan Tan Weihua Fang key laboratory of environmental change and Natural disaster of Ministry of Education Faculty of Geographical Science Beijing Normal University Academy of disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University

Tropical cyclones(TCs) cause catastrophic loss in many coastal areas of the world. TC wind hazard maps can play an important role in disaster management. A good representation of local factors reflecting the effects of spatially heterogeneous terrain and land cover is critical to evaluation of TC wind hazard. Very few studies, however,provide global wind hazard assessment results that consider detailed local effects. In this study, the wind fields of historical TCs were simulated with parametric models in which the planetary boundary layer models explicitly integrate local effects at 1 km resolution. The topographic effects for eight wind directions were quantified over four types of terrain(ground, escarpment, ridge, and valley),and the surface roughness lengths were estimated from a global land cover map. The missing TC parameters in the best track datasets were reconstructed with local regression models. Finally, an example of a wind hazard map in the form of wind speeds under a 100-year return period and corresponding uncertainties was created based on a statistical analysis of reconstructed historical wind fields over seven of the world's ocean basins.

关键词： Surface roughness Topographic effect Tropical cyclone Wind field model Wind hazard

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