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Sensitivity analysis of the De Nitrification and De Composition model for simulating regional carbon budget at the wetlandgrassland area on the Zoige Plateau,China

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Journal of Mountain Science 2016年第7期13卷 1200-1216页

作者： WANG Ji-yan li ai-nong JIN Hua-an Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Although mathematical models(e.g., De Nitrification and De Composition(DNDC) provide a powerful tool to study regional carbon budget, it is still difficult to obtain accurate simulation results because there exists large uncertainties in modeling regional carbon budget. Through the investigation on the sensitivity of model output parameters to the input parameters, sensitivity analysis(SA) has been proved to be able to identify the key sources of uncertainties and be helpful to reduce the model uncertainties. However, some input parameters with discrete values(e.g., land use type and soil type) and the regional effect of the sensitive parameters were rarely examined in SA. In this paper, taking the Zoige Plateau as a case area, we combined the one-factor-ata-time(OAT) with Extended Fourier Amplitude Sensitivity Test(EFAST) to conduct a SA of DNDC for simulating the regional carbon budget, including Gross Primary Productivity(GPP), Net Primary Productivity(NPP), Net Ecosystem Productivity(NEP), autotrophic respiration(Ra), soil microbial heterotrophic respiration(Rh) and ecosystem respiration(Re). The result showed that the combination of OAT and EFAST could test the contribution of the input parameters with discrete values to the output parameters. In DNDC model, land use type and soil type had a significant impact on the regional carbon budget of the Zoige Plateau, and daily temperature was also confirmed to be one of the most important parameters for carbon budget. For the other input parameters, with the change of land use type or soil type at regional scale, the sensitive parameters of carbon budget would vary accordingly. The SA results would provide scientific evidence to optimize DNDC model and they suggested that we should pay attention to the spatial/temporal effect of SA and try to use the appropriate data in simulation of the regional carbon budget.

关键词： Sensitivity analysis OAT EFAST DNDC model Carbon budget Zoige Plateau

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Response of Lakes to Climate Change in Xainza Basin Tibetan Plateau Using Multi-Mission Satellite Data from 1976 to 2008

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Journal of Mountain Science 2015年第3期12卷 604-613页

作者： YI Gui-hua DENG Wei li ai-nong ZHANG Ting-bin Institute of Mountain Hazards and Environment Chinese Academy of Science College of Administrative Science Chengdu University of Technology College of Earth Sciences Chengdu University of Technology Key Laboratory of Geoscience Spatial Information Technology Ministry of Land and Resources of the P.R. China

Changes in the lake areas of Xainza basin in the past 33 years （1976 to 2008） were studied using Landsat data from Multispectral Scanners （1973- 1977）, Thematic Mapper （1989-1992, 2007-2009）, and Enhanced Thematic Mapper Plus （1999-2002）. The results indicated that lakes in the study area evidently expanded from 1976 to 2008, with total expansion of 1512.64km2. The mean annual air temperature presented an upward trend with certain fluctuations from 1966 to 2008. The air temperature rise rates in the cold season （o.31~C/loa） were higher than those in the hot season （0.24℃/1oa）, in the Xainza station example. Precipitation exhibited evident seasonal differences. Mean annual precipitation in hot season is 281.48 mm and cold season is 32.66 mm from 1966 to 2008 in study area. Precipitation in the hot season was the major contributor to the increase in annual precipitation. Grey relational analysis （GRA） was used to study the response of lake areas to climatic factors. The mean air temperature and precipitation were selected as comoared series, and the lake areas were regarded as the reference series. The grey relational grade （GRG） between compared series and reference series were calculated through GRA. The results indicated that changes in lake areas were mainly affected by climatic factors in the hot season. Lakes in this region were classified into three grades, namely, Grades I, II, and III according to the recharge source and elevation. The GRGs of each series varied for different grade lakes： the area of Grade III lakes were the most relevant to the hot season factors, the GRGs of precipitation and air temperature were 0.7570 and 0.6606; followed by the Grade II lakes; Grade I lakes were more sensitive to the air temperature.

关键词： Lake Climate change Remote sensing Grey relational analysis Xainza basin TibetanPlateau

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Mechanism of subsidence-buckling and instability of slopes in thick-layered rigid rock under mining

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Journal of Mountain Science 2023年第8期20卷 2370-2387页

作者： DENG Jie ZHAO Jian-jun Lai Qi-yi li ai-nong XIE Ming-li li Qing-miao ZHAO Xiao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China POWERCHINA Chengdu Engineering Corporation limited Chengdu 610072China

The deformation and failure of mining slopes in layered rocks predominantly result from shear ***,the instability process of the Pusa rock avalanche in Guizhou,China,revealed a unique damage phenomenon:prominent breaking and toppling of rock blocks occurred in the central section of the mountain,with a lack of commonly observed shear landslide *** paper aims to investigate the underlying reasons behind this distinctive damage *** study employs various methods including geological survey,UAV aerial survey,physical simulation,and discrete element numerical *** findings indicate that the geological conditions,characterized by a hard upper layer and a soft lower layer along with underground mining activities,play a significant role in triggering the ***,the presence of a columnar structured rock mass emerges as the primary factor influencing the instability of the Pusa rock *** elucidate the mining failure mechanism of the rock mass with vertical joints,we propose a"subsidence-buckling"failure *** the subsidence and collapse of the roof rock mass in the goaf,the columnar rock mass in the upper and middle portions of the slope undergoes deflection and deformation,forming a three-hinged arch *** structural configuration converts the pressure exerted by the overlying rock mass into both vertical pressure and lateral *** the influence of external loads,the slope experiences buckling failure,ultimately leading to instability upon *** shedding light on these findings,this study contributes to a better understanding of the spatiotemporal evolution of mining slope fractures and their impact on slope stability.

关键词： Mining landslide Failure mechanism Block structure Failure characteristics Soft-hard interbedding

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Validation of Global Land Surface Satellite (GLASS) Downward Shortwave Radiation Product in the Rugged Surface

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Journal of Mountain Science 2013年第5期10卷 812-823页

作者： JIN Hua-an li ai-nong BIAN Jin-hu ZHANG Zheng-jian HUANG Cheng-quan li Meng-xue Institute of Mountain Hazards and Environment Chinese Academy of Sciences Department of Geographical Sciences University of MarylandCollege Park

The downward shortwave radiation(DSR) is an essential parameter of land surface radiation budget and many land surface models that characterize hydrological,ecological and biogeochemical *** new Global LAnd Surface Satellite(GLASS) DSR datasets have been generated recently using multiple satellite data in *** study investigates the performances of direct comparison approach,which is mostly used for validation of surface insolation retrieved from satellite data over the plain area,and indirect comparison approach,which needs a fine resolution map of DSR as reference,for validation of GLASS DSR product in time-steps of 1 and 3 hours over three Chinese Ecosystem Research Network sites located in the rugged *** suggest that it probably has a large uncertainty to assess GLASS DSR product using the direct comparison method between GLASS surface insolation and field measurements over complex terrain,especially at *** 3,000 m station with root mean square error of 279.04 and 229.06 W/m2in time-steps of 1 and 3 hours,*** improvement for validation of GLASS DSR product in the rugged surface is suggested by generation of a fine resolution map of surface insolation and comparison of the aggregated fine resolution map with GLASS product in the rugged *** validation experience demonstrates that the GLASS DSR algorithm is satisfactory with determination coefficient of 0.83 and root mean square error of 81.91W/m2over three Chinese Ecosystem Research Network sites,although GLASS product overestimates DSR compared to the aggregated fine resolution map of surface insolation.

关键词： Downward shortwave radiation Validation Complex terrain

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Auto-registration and Orthorecification Algorithm for the Time Series HJ-1A/B CCD Images

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Journal of Mountain Science 2013年第5期10卷 754-767页

作者： BIAN Jin-hu li ai-nong JIN Hua-an LEI Guang-bin HUANG Cheng-quan li Meng-xue Digital Mountain and Remote Sensing Application Center Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences University of Chinese Academy of Sciences Department of Geography University of Maryland2181 LeFrak HallCollege Park

How to deal with geometric distortion is an open problem when using the massive amount of satellite images at a national or global scale, especially for multi-temporal image analysis. In this paper, an algorithm is proposed to automatically rectify the geometric distortion of time-series CCD multi- spectral data of small constellation for environmental and disaster mitigation （HJ-1A/B） which was launched by China in 2008. In this algorithm, the area-based matching method was used to automatically search tie points firstly, and then the polynomial function was introduced to correct the systematic errors caused by the satellite motion along the roll, pitch and yaw direction. The improved orthorectification method was finally used to correct pixel displacement caused by off-nadir viewing of topography, which are random errors in the images and cannot be corrected by the polynomial equation. Nine scenes of level 2 HJ CCD images from one path/row were taken as the warp images to test the algorithm. The test result showed that the overall accuracy of the proposed algorithm was within 2 pixels （the average residuals were 37.8 m, and standard deviations were 19.8 m）. The accuracies of 45.96% validation points （VPs） were within 1 pixel and 90.33% VPs were within 2 pixels. The discussion showed that three main factors including the distortion patterns of HJ CCD images, pereent of cloud cover and the varying altitude of the satellite orbit may affect the search of tie points and the accuracy of results. Although the influence of varying altitude of the satellite orbits is less than the other factors, it is noted that detailed satellite altitude information should be given in the future to get a more precise result. The proposed algorithm should be an efficient tool for the geo-correction of HJ CCD multi-spectral images.

关键词： HJ time series images Auto-geocorrection Topographic correction Widecoverage CCD cameras

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Landscape Pattern Evolution Processes of Alpine Wetlands and Their Driving Factors in the Zoige Plateau of China

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Journal of Mountain Science 2013年第1期10卷 54-67页

作者： Bai Jun-hong LU Qiong-qiong WANG Jun-jing ZHAO Qing-qing OUYANG Hua DENG Wei li ai-nong State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Zoige Plateau wetlands are located in the northeastern corner of the Qinghai-Tibet *** landscape pattern evolution processes in the Zoige Plateau and their driving factors were identified by analyzing the dynamic changes in landscape modification and conversion and their dynamic rates of alpine wetlands over the past four *** results showed that the landscape conversion between wetlands and non-wetlands mainly occurred during the period from 1966 to *** marsh wetland area converted from lake and river wetlands was larger because of swamping compared to other wetland ***,the larger area of marsh wetlands was also converted to lake wetlands more than other types of *** modification processes mainly occurred among natural wetland landscapes in the first three *** conversions were observed between wetland and nonwetland landscapes(i.e.,forestland,grassland,and other landscapes) in the Zoige *** natural wetland landscapes such as river,lake and marsh wetlands showed a net loss over the past four decades,whereas artificial wetland landscapes(i.e.,paddy field and reservoir and pond wetlands) showed a net *** annual dynamic rate of the whole wetland landscape was 0.72%,in which the annual dynamic rate of river wetlands was the highest,followed by lake wetlands,while marsh wetlands had the lowest dynamic *** integrated landscape dynamic rate showed a decreasing trend in the first three *** changes in wetland landscape patterns were comprehensively controlled by natural factors and human activities,especially human activities play an important role in changing wetland landscape patterns.

关键词： Zoige Plateau Alpine wetland Landscape pattern Modification Conversion Driving factors

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天然牙和牙科材料的摩擦学研究现状与进展

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摩擦学学报 2005年第4期25卷 379-384页

作者：熊菲周新聪李爱农严新平武汉理工大学可靠性工程研究所湖北武汉430063

评述了口腔摩擦学系统的特征与参数、口腔磨损环境以及天然牙和牙科材料的磨损机理,简要介绍了目前国内外关于天然牙和牙科材料的磨损性能测量方法以及口腔磨损环境模拟测试系统的研究现状,指出今后在考虑化学环境和各种力等因素协同作... 详细信息

评述了口腔摩擦学系统的特征与参数、口腔磨损环境以及天然牙和牙科材料的磨损机理,简要介绍了目前国内外关于天然牙和牙科材料的磨损性能测量方法以及口腔磨损环境模拟测试系统的研究现状,指出今后在考虑化学环境和各种力等因素协同作用条件下,应加强牙科材料的磨损机理、磨损预测模型及其标准的实验方法和模拟系统的建立等方面的研究.

关键词：天然牙牙科材料磨损机理

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中国山地起伏度计算中地形自适应滑动窗口获取与验证

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地理与地理信息科学 2017年第4期33卷 34-39页

作者：南希李爱农景金城中国科学院水利部成都山地灾害与环境研究所数字山地与遥感应用中心四川成都610041 成都理工大学地球科学学院四川成都610059

在地形起伏度研究中,多采用固定大小的"最佳计算窗口"进行运算,尚未见随地形特征变化的自适应窗口。针对单值最优窗口固有的不确定性,该文尝试构建适应局部地形的窗口阵列。首先对均值变点法作拓展与调整,遍历栅格单元,并求每一栅格处... 详细信息

在地形起伏度研究中,多采用固定大小的"最佳计算窗口"进行运算,尚未见随地形特征变化的自适应窗口。针对单值最优窗口固有的不确定性,该文尝试构建适应局部地形的窗口阵列。首先对均值变点法作拓展与调整,遍历栅格单元,并求每一栅格处最佳窗口取值,从而得到地形自适应的滑动窗口。最后,使用SRTM和ASTR GDEM在山地范围内进行实验与检验,结果表明:最佳计算窗口的尺寸随地形发生变化;与单值窗口相比,基于地形自适应窗口求得的起伏度与地表实际情况更为吻合、细节特征更加清晰、精度更高;地形自适应窗口较好地改善了单值计算窗口对高程数据源敏感的情况。中国山地自适应滑动窗口以3.57km2、4.28km2、5.06km2为主,其统计特征符合正态分布,总体均值可与全局单值窗口相互印证。

关键词：起伏度地形自适应滑动窗口变点法山地

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Discussion on Landscape Ecosystem Planning of Small Basins in the Qinghai-Tibet Plateau——Taking Nieruzangbu Basin as an Example

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Wuhan University Journal of Natural Sciences 2003年第03B期8卷 940-948页

作者： G He Xiao-rong, li Hui-xia, li ai-nong, Zhou Hong-yi, Wang Xiao-danInstitute of Mountain Hazards and Environment. Chinese Academy of Sciences, Chengdu 610041, Sichuan. China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 SichuanChina

In this paper, taking Nieruzanghu as an example, it is discussed that how to plan landscapes of small basin in the Qinghai-Tibet Plateau. With analyzed the status and character of landscape structure through the use of landscape diversity indexes and landscape dominant indexes, some major problems in the landscape ecosystem are pointed out. On the basis of regional restrictive principle and compliance principle of resources, environment and economy, Nieruzangbu Basin is divided into three landscape function areas. According to the demands of each function area, landscape structure planning is carried out to improve ecological environment through optimization and adjustment of landscape structure in Nieruzangbu Basin.

关键词： the Qinghai-Tibet Plateau Nieruzangbu Basin landscape landscape planning

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Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong li Peng ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

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