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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 *** 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 ***,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 *** seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen *** 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 *** significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing *** findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of *** 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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植被最大光能利用率的模拟方法对比评估

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遥感学报 2024年第3期28卷 649-660页

作者：赵涔良朱文泉谢志英北京师范大学遥感科学国家重点实验室北京100875 北京师范大学地理科学学部北京市陆表遥感数据产品工程技术研究中心北京100875

光能利用率模型是一种基于遥感数据估算植被生产力的参数模型,其核心参数最大光能利用率(LUE_(max))在早期模型中被认为是一个适用于所有植被类型的固定值,而从MODIS-LUE模型开始则成为一个依植被类型而变化的参数,直至近年来被认为需... 详细信息

光能利用率模型是一种基于遥感数据估算植被生产力的参数模型,其核心参数最大光能利用率(LUE_(max))在早期模型中被认为是一个适用于所有植被类型的固定值,而从MODIS-LUE模型开始则成为一个依植被类型而变化的参数,直至近年来被认为需要进一步根据植被的物候及生理状态而进行实时调整。相较于基于静态LUE_(max)参数估算的植被生产力,尽管目前基于季节性动态LUE_(max)参数估算的植被生产力都显示出更高的精度,但这些研究结果大多局限于特定的植被类型或空间范围,而在更广泛的植被类型和区域的适用性以及不同的动态LUE_(max)参数在地域间的适用性差异等问题尚不明确。因此,本文针对目前已有的3种典型动态LUE_(max)参数模拟方法 (基于叶绿素遥感指数、基于LAI季节调节因子、马尔可夫链蒙特卡洛模拟),通过采用相同的生产力估算与评估数据集(FLUXNET 2015数据集)和模型结构(MODIS-LUE模型结构)对该3种方法进行了对比分析。结果显示,不同的动态LUE_(max)参数在各植被类型上的季节性变化特征有明显差异,总体上呈现出单峰、“U”型和水平波动3种特征。相比于原静态LUE_(max)参数,基于各动态LUE_(max)参数估算的总初级生产力(GPP)精度均有一定的提升,但是依赖于特定的动态LUE_(max)参数模拟方法,其中的马尔可夫链蒙特卡洛方法对LUE_(max)参数有着较好的模拟效果,并且其GPP的估算精度在全植被类型的所有时段都不低于基于原静态LUE_(max)参数的结果 (相比静态参数的GPP结果,RMSE总体降低了10.9 g/(m^(2)·月),以碳计),尤其在郁闭灌丛、落叶针叶林以及常绿阔叶林上的提升效果十分明显。本文研究结果可为植被生产力光能利用率模型的不确定性分析以及发展新的模型提供依据。

关键词：遥感植被生产力总初级生产力光能利用率模型最大光能利用率参数评估

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Integration of multiple climate models to predict range shifts and identify management priorities of the endangered Taxus wallichiana in the Himalaya–Hengduan Mountain region

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Journal of Forestry Research 2020年第6期31卷 2255-2272页

作者： Peixian Li wenquan zhu Zhiying Xie Kun Qiao State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875People’s Republic of China Beijing Engineering Research Center for Global Land Remote Sensing Products Institute of Remote Sensing Science and EngineeringFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875People’s Republic of China

Taxus wallichiana Zucc.(Himalayan yew)is subject to international and national conservation measures because of its over-exploitation and decline over the last 30 *** the impact of climate change on ***’s distribution might help protect the wild populations and plan effective ex situ measures or cultivate *** the complexity of climates and the uncertainty inherent in climate modeling for mountainous regions,we integrated three Representative Concentration Pathways(RCPs)(i.e.,RCP2.6,RCP4.5,RCP8.5)based on datasets from 14 Global Climate Models of Coupled Model Intercomparison Project,Phase 5 to:(1)predict the potential distribution of *** under recent past(1960–1990,hereafter‘‘current’’)and future(2050s and 2070s)scenarios with the species distribution model MaxEnt.;and(2)quantify the climatic factors influencing the *** respond to the future warming climate scenarios,(1)highly suitable areas for *** would decrease by 31–55%at a rate of 3–7%/10a;(2)moderately suitable areas would decrease by 20–30%at a rate of 2–4%/10a;(3)the average elevation of potential suitable sites for *** would shift upslope by 390 m(15%)to 948 m(36%)at a rate of 42–100 m/*** annual temperature(contribution rate ca.61%),isothermality and temperature seasonality(20%),and annual precipitation(17%)were the main climatic variables affecting *** *** protected areas and suitable planting areas must be delimited from the future potential distributions,especially the intersection areas at different suitability *** is helpful to promote the sustainable utilization of this precious resource by prohibiting exploitation and ex situ restoring wild resources,as well as artificially planting considering climate suitability.

关键词： Taxus wallichiana Zucc. Climate warming Potential distribution MaxEnt Conservation and cultivation

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Comprehensive analysis of the impact of climatic changes on Chinese terrestrial net primary productivity

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Chinese Science Bulletin 2007年第23期52卷 3253-3260页

作者： zhu wenquan PAN YaoZhong YANG XiaoQiong SONG GuoBao State Key Laboratory of Earth Surface Processes and Resource Ecology College of Resources Science & Technology Beijing Normal University Beijing 100875 China

Recent climatic changes have affected terrestrial net primary productivity (NPP). This paper presents an investigation of the impact of climatic changes on Chinese terrestrial vegetation NPP by analyzing 18 years’ (1982 to 1999) climatic data and satellite observations of vegetation activity. Results indicate that climatic changes in China have eased some critical climatic constraint on plant growth. (1) From 1982 to 1999, modeled NPP increased by 1.42%·a-1 in water-limited regions of Northwest China, 1.46%·a-1 in temperature-limited regions of Northeast China and Tibet Plateau, and 0.99%·a-1 in radia- tion-limited regions of South China and East China. (2) NPP increased by 24.2%, i.e. 0.76 petagram of carbon (Pg C) over 18 years in China. Changes in climate (with constant vegetation) directly contrib- uted nearly 11.5% (0.36 Pg C). Changes in vegetation (with constant climate) contributed 12.4% (0.40 Pg C), possibly as a result of climate-vegetation feedbacks, changes in land use, and growth stimula- tion from other mechanisms. (3) Globally, NPP declined during all three major El Ni-o events (1982 to 1983, 1987 to 1988, and 1997 to 1998) between 1982 and 2000, but Chinese vegetation productivity re- sponded differently to them because of the monsoon dynamics. In the first three events (1982 to 1983, 1987 to 1988, and 1992), Chinese vegetation NPP declined, while in the later two events (1993, 1997 to 1998) increasing obviously.

关键词：气候变化遥控技术中国实验数据

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A correction technique for false topographic perception of remote-sensing images based on an inverse topographic correction techniqu

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International Journal of Digital Earth 2016年第10期9卷 1021-1034页

作者： Donghai Zhang wenquan zhu Xiang Chen Zhoutao Zheng Xiafei Zhou Tao Jiang State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingPeople’s Republic of China College of Resources Science and Technology Beijing Normal UniversityBeijingPeople’s Republic of China Department of Emergency Management Arkansas Tech UniversityRussellvilleARUSA

The false topographic perception phenomenon(FTPP)refers to the visual misperception in remote-sensing images that certain types of terrains are visually interpreted as other types in rugged lands,for example,valleys as ridges and troughs as *** this reason,the FTPP can influence the visualization and interpretation of images to a great *** scrutinize this problem,the paper firstly reviews and tests the existing FTPP-correction techniques and identifies the inverse slope-matching technique as an effective approach to visually enhance remote-sensing images and retain the colour *** paper then proposes an improved FTPP-correction procedure that incorporates other image-processing techniques(*** stretch,histogram matching,and flat-area replacement)to enhance the performance of this technique.A further evaluation of the proposed technique is conducted by applying the technique to various study areas and using different types of remote-sensing *** result indicates the method is relatively robust and will be a significant extension to geovisual analytics in digital earth research.

关键词： Remote sensing false topographic perception phenomenon topographic correction mapping visual interpretation

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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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SIMULATION OF MAXIMUM LIGHT USE EFFICIENCY FOR SOME TYPICAL VEGETATION TYPES IN CHINA

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Chinese Science Bulletin 2006年第4期51卷 457-463页

作者： zhu wenquan PAN Yaozhong HE Hao YU Deyong HU Haibo Key Laboratory of Environmental Change and Natural Disaster ofMinistry of Education College of Resources Science and TechnologyBeijing Normal University Beijing 100875 China Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China

Maximum light use efficiency (εmax) is a key parameter for the estimation of net primary pro-ductivity (NPP) derived from remote sensing data. There are still many divergences about its value for each vegetation type. The εmax for some typical vegetation types in China is simulated using a modi-fied least squares function based on NOAA/AVHRR remote sensing data and field-observed NPP data. The vegetation classification accuracy is introduced to the process. The sensitivity analysis of εmax to vegetation classification accuracy is also conducted. The results show that the simulated values of εmax are greater than the value used in CASA model, and less than the values simulated with BIOME-BGC model. This is consistent with some other studies. The rela-tive error of εmax resulting from classification accuracy is ?5.5%―8.0%. This indicates that the simulated values of εmax are reliable and stable.

关键词：植物生理学植被类型最大日光利用效率遥感净初级生产力

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青藏高原各主要植被类型特征及环境差异

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生态学报 2024年第7期44卷 2955-2970页

作者：张慧朱文泉史培军赵涔良刘若杨唐海萍王静爱何邦科北京师范大学遥感科学国家重点实验室北京100875 北京师范大学地理科学学部北京市陆表遥感数据产品工程技术研究中心北京100875 北京师范大学应急管理部教育部减灾与应急管理研究院北京100875 北京师范大学地理科学学部北京100875 青海省人民政府北京师范大学高原科学与可持续发展研究院西宁810016

青藏高原高海拔引起的地形、气候和土壤空间差异造就了其独特的植被类型及其空间变化,当前研究缺乏针对青藏高原全域范围内各植被类型特征和环境差异的定量与系统性分析。针对青藏高原特殊的地理环境和植被类型,选用植被、地形、土壤、... 详细信息

青藏高原高海拔引起的地形、气候和土壤空间差异造就了其独特的植被类型及其空间变化,当前研究缺乏针对青藏高原全域范围内各植被类型特征和环境差异的定量与系统性分析。针对青藏高原特殊的地理环境和植被类型,选用植被、地形、土壤、气候4个维度共计58个空间化指标,采用频数分布统计方法对这些指标开展了定量分析,系统揭示了青藏高原全域范围内各主要植被类型的特征及环境差异。通过定量分析发现,大部分的环境及植被特征指标对青藏高原各主要植被类型的区分度较高,其中,遥感归一化植被指数、植被净初级生产力、裸地覆盖度、海拔、土壤温度、年最低温度、年总蒸散发7个指标对青藏高原各主要植被类型的区分度较高。揭示的青藏高原各主要植被类型的特征及环境差异,可提高灌丛和草地之间、各草地类型之间、高山苔原-垫状-稀疏植被与其他植被类型之间的可区分性,有助于解决青藏高原植被精细分类中广泛存在的灌丛和草地区分、草地类型细分、高山苔原-垫状-稀疏植被识别和山地垂直地带植被识别四个难点问题。研究结果一方面可服务于青藏高原的植被精细分类,另一方面也可服务于青藏高原的自然地带划分、生物多样性和生态系统功能评估、地表物质循环研究等。

关键词：青藏高原植被类型环境特征植被特征频数分布统计

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Box-Behnken响应面法优化厚朴酚与小檗碱共载脂质体的处方工艺

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中国医院药学杂志 2024年第7期44卷 796-801,858页

作者：马晓星隋小宇刘畅李慧朱文全徐涛张宏宇李永吉韩翠艳齐齐哈尔医学院药学院黑龙江齐齐哈尔161006 黑龙江中医药大学药学院黑龙江哈尔滨150040 齐齐哈尔医学院黄芪产业研究院黑龙江齐齐哈尔161006

目的:采用Box-Behnken响应面法优化厚朴酚与小檗碱共载脂质体(Lip-MB)的处方工艺。方法:HPLC法同时测定小檗碱、厚朴酚含量。薄膜分散结合pH梯度法制备Lip-MB。在单因素考察基础上,采用Box-Behnken响应面法,以小檗碱和厚朴酚包封率为指... 详细信息

目的:采用Box-Behnken响应面法优化厚朴酚与小檗碱共载脂质体(Lip-MB)的处方工艺。方法:HPLC法同时测定小檗碱、厚朴酚含量。薄膜分散结合pH梯度法制备Lip-MB。在单因素考察基础上,采用Box-Behnken响应面法,以小檗碱和厚朴酚包封率为指标,优选Lip-MB最佳处方和工艺。同时对Lip-MB形态、粒径、Zeta电位、释放度进行评价。结果:最优处方工艺为HSPC与CHOL质量比3.6∶1、药脂比1∶23、外水相pH 8.4、孵育温度59℃。小檗碱和厚朴酚在Lip-MB中的包封率分别为(91.74±1.91)%和(83.17±1.05)%。平均粒径为(106.6±2.60)nm,Zeta电位为(–9.88±2.33)mV,小檗碱和厚朴酚84 h累积释放度分别为98.41%和81.83%。结论:Box-Behnken响应面法所建立的模型可用于Lip-MB的处方工艺优化。优化的Lip-MB包封率较高,粒径小,分布均匀,具有缓释作用。

关键词：小檗碱厚朴酚 Box-Behnken响应面法脂质体

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Mesoporous carbon as a carrier for celecoxib:The improved inhibition effect on MDA-MB-231 cells migration and invasion

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Asian Journal of Pharmaceutical Sciences 2014年第2期9卷 82-91页

作者： wenquan zhu Qinfu Zhao Xin Zheng Zhiwen Zhang Tongying Jiang Yaping Li Siling Wang School of Pharmaceutics Shenyang Pharmaceutical UniversityNo.103 Wenhua RoadShenyangLiaoning Province 110016China Center of Pharmaceutics Shanghai Institute of Materia MedicaChinese Academy of SciencesNo.501 Haike RoadShanghai 201203China

In the current study,mesoporous carbon(MC)with pore volume(1.53 cm3/g)and pore size(9.74 nm)was successfully prepared as a carrier for celecoxib(CEL).Celecoxib was loaded into the pore channels of MC using three different methods:solvent evaporation method,absorption method and physical mixing ***-state characterization methods,such as SEM,TEM,BET,DSC and XRD were used to systematically investigate the process of the drug loading *** tests were performed to examine the effects of MC on the release of ***,the cytotoxicity,wound healing,migration and invasion experiments were carried out to measure the contribution of MC to the anti-tumor metastasis ability of celecoxib on MDA-MB-231 *** results showed that CEL could be kept in a non-crystalline state when they were incorporated into the MC using the solvent evaporation method or absorption *** dissolution rate of CEL released from MCS(Mesoporous carbon e Celecoxib e Solvent evaporation method)and MCA(Mesoporous carbon e Celecoxib e Absorption evaporation method)was all significantly higher than that of pure *** cumulative release for MCS within the 5 min was up to 51.86%.MCS enhanced the inhibitory effect of CEL on the migration and invasion of MDAMB-231 cells.

关键词： Mesoporous carbon Carrier Dissolution Migration Invasion

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