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Chinese Science Bulletin 2001年第11期46卷 895-901页

作者： Guoshun Zhuang Jinghua Guo Hui Yuan chengyi zhao Beijing Normal Univ Ctr Atmospher Environm Study Beijing 100875 Peoples R China

The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollution elements As, Sb and Se were higher than those in the non-dust storm days. This indicated that As, Sb and Se resulted from the pollution sources of those areas, through which the dust storm passed during their long-range transport, in addition to the local pollution sources in Beijing. The enrichment factors of the Pb, Zn, Cd and Cu were much less than those in the non-dust storm days, suggesting that the local pollution sources in Beijing area contributed to them mostly. The enrichment factors of elements Al, Fe, Sc, Mn, Na, Ni, Cr, V and Co were close to 1, showing that these elements originated from crust. The concentration of S in the dust storm was -10 μg · m-3,4 times as high as that in non-dust storm. S in the aerosols resulted from the adsorption of gaseous SO2 and the consequent

关键词： dust storm aerosols particles pollution sources trans- formation global change.

Competition between Populus euphratica and Tamarix ramosissima seedlings under simulated high groundwater availability

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Journal of Arid Land 2016年第2期8卷 293-303页

作者： WU Guilin JIANG Shaowei LIU Weiyang zhao chengyi LI Jun State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China College of Plant Science Tarim UniversityAlar 843300China

Desert riparian plants experience high variability in water availability due to hydrological fluctuations. How riparian plants can survive with low water availability has been well studied, however, little is known about the effects of high water availability on plant community structuring. We conducted a mesocosm experiment to test whether seedling competition under simulated high groundwater availability can explain the shift of co-dominance of Populus euphratica and Tamarix ramosissima in early communities to P. euphratica dominance in mature ones along the Tarim River in northwestern China. Seedlings of these two plant species were grown in monoculture and mixture pools with high groundwater availability. Results indicated that the above-ground biomass and relative yield of T. ramosissima were higher than those of P. euphratica. The competitive advantages of T. ramosissima included its rapid response in growth to groundwater enrichment and its water spender strategy, as evidenced by the increased leaf biomass proportion and the inert stomatal response to leaf-to-air vapor pressure deficit （VPD）. In comparison, P. euphratica showed a conservative strategy in water use, with a sensitive response to leaf-to-air VPD. Result of the short-term competition was inconsistent with the long-term competition in fields, suggesting that competition exclusion is not the mechanism structuring the desert riparian plant communities. Thus, our research highlights the importance of mediation by environmental fluctuations （such as lessening competition induced by disturbance） in structuring plant communities along the Tarim riparian zones.

关键词： community succession vapor pressure deficit (VPD) stomatal conductance riparian plant water usestrategy

Regional partitioning of agricultural non-point source pollution in China using a projection pursuit cluster model

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Journal of Arid Land 2011年第4期3卷 278-284页

作者： XinHu LI chengyi zhao Bin WANG Garry FENG State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China College of Water Conservancy and Building Engineering Northeast Agricultural University Harbin 100500 China Department of Biological Systems Engineering Washington State University Washington 99164-6120 USA

A projection pursuit cluster（PPC） model was used to analyze the regional partitioning of agricultural non-point source pollution in *** environmental factors impacting the agricultural non-point source pollution were compiled into a projection index to set up the projection index function.A novel optimization algorithm called Free search（FS） was introduced to optimize the projection direction of the PPC *** making the appropriate improvements as we explored the use of the algorithm,it became simpler,and developed better exploration ***,the multi-factor problem was converted into a single-factor cluster,according to the projection,which successfully avoided subjective disturbance and produced objective *** cluster results of the PPC model mirror the actual regional partitioning of the agricultural non-point source pollution in China,indicating that the PPC model is a powerful tool in multi-factor cluster analysis,and could be a new method for the regional partitioning of agricultural non-point source pollution.

关键词： nonpoint pollution regional partitioning projection pursuit Free search

Pedotransfer functions for predicting bulk density of coastal soils in East China

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Pedosphere 2023年第6期33卷 849-856页

作者： Guanghui ZHENG Caixia JIAO Xianli XIE Xuefeng CUI Gang SHANG chengyi zhao Rong ZENG School of Geographic Sciences Nanjing University of Information Science&TechnologyNanjing 210044China Meteorology and Climate Centre School of Mathematics and StatisticsUniversity College DublinBelfieldDublin 4Ireland Institute of Soil Science Chinese Academy of ScienceNanjing 210008China School of Systems Science Beijing Normal UniversityBeijing 100875China

Soil bulk density(BD) is an important physical property and an essential factor for weight-to-volume conversion. However, BD is often missing from soil databases because its direct measurement is labor-intensive, time-consuming, and sometimes impractical, particularly on a large scale. Therefore, pedotransfer functions(PTFs) have been developed over several decades to predict BD. Here, six previously revised PTFs(including five basic functions and stepwise multiple linear regression(SMLR)) and two new PTFs, partial least squares regression(PLSR) and support vector machine regression(SVMR), were used to develop BD-predicting PTFs for coastal soils in East China. Predictor variables included soil organic carbon(SOC) and particle size distribution(PSD). To compare the robustness and reliability of the PTFs used, the calibration and prediction processes were performed 1 000 times using the calibration and validation sets divided by a random sampling algorithm. The results showed that SOC was the most important predictor, and the revised PTFs performed reasonably although only SOC was included. The PSD data were useful for a better prediction of BD, and sand and clay fractions were the second and third most important properties for predicting BD. Compared to the other PTFs, the PLSR was shown to be slightly better for the study area(the average adjusted coefficient of determination for prediction was 0.581). These results suggest that PLSR with SOC and PSD data can be used to fill in the missing BD data in coastal soil databases and provide important information to estimate coastal carbon storage, which will further improve our understanding of sea-land interactions under the conditions of ongoing global warming.

关键词： partial least squares regression particle size distribution soil organic carbon stepwise multiple linear regression support vector machine regression

Effect of groundwater depth on riparian plant diversity along riverside-desert gradients in the Tarim River

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Journal of Plant Ecology 2019年第3期12卷 564-573页

作者： Yong Zeng chengyi zhao Jun Li Yan Li Guanghui Lv Tong Liu State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences818 South Beijing RoadUrumqi 830011China College of Resources and Environment Sciences Xinjiang University14 Shengli RoadUrumqi 830046China University of Chinese Academy of Sciences 55 East Zhongguancun East RoadBeijing 100049China Land Science Research Center Nanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China College of Life Sciences Shihezi University4 North RoadShihezi 832003XinjiangChina

Aims Riparian plant diversity is sensitive to changes in groundwater in arid ***,little is known about how plant diversity responds to changes in environment along riverside-desert gradi-ents in riparian *** objectives were to(i)identify ri-parian plant diversity along riverside-desert gradients in Tarim desert riparian forests,(ii)analyze the impact of environment variables on plant diversity,(iii)determine the optimum groundwater depth for different plant *** Six transects 90 quadrats(with each size 100 m×100 m)distributed vertically to river bed along riverside-desert gradients~30 km in length were *** each quadrat,the morphological features of riparian plant communities were measured,and the groundwater depth,soil water,soil salinity,soil nutrient were also monitored at same *** Finding Three distinct vegetation communities were identified based on cover and richness in the tree,shrub and herb layers:the riparian zone,the transitional zone and the desert margin *** spe-cies were indicators of the three vegetation *** plant diversity was influenced by groundwater depth,distance from river,soil moisture content,soil salinity and soil nutrient by redundancy *** response to groundwater depth,the op-timal groundwater depths for species diversity,evenness and shrub cover were 2.8,2.7 and 3.7 m,***,maintaining high plant diversity requires managers to ensure stable groundwater depth for different plant life-forms rather than for some of them.

关键词： vegetation community distance from river groundwater depth Tarim River

Projection of precipitation extremes over South Asia from CMIP6 GCMs

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Journal of Arid Land 2023年第3期15卷 274-296页

作者： Adnan ABBAS Asher S BHATTI Safi ULLAH Waheed ULLAH Muhammad WASEEM zhao chengyi DOU Xin Gohar ALI Land Science Research Center Nanjing University of Information Science&TechnologyNanjing 210044China Department of Geology Bacha Khan UniversityCharsadda 24420Pakistan Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Center of Excellence in Water Resources University of Engineering and TechnologyLahore 54890Pakistan Pakistan Meteorological Department Sector H-8/2Islamabad 44000Pakistan

Extreme precipitation events are one of the most dangerous hydrometeorological disasters,often resulting in significant human and socio-economic losses *** is therefore important to use current global climate models to project future changes in precipitation *** present study aims to assess the future changes in precipitation extremes over South Asia from the Coupled Model Intercomparison Project Phase 6(CMIP6)Global Climate Models(GCMs).The results were derived using the modified Mann-Kendall test,Sen's slope estimator,student's t-test,and probability density function *** extreme precipitation indices were assessed,including wet days(RR1mm),heavy precipitation days(RR10mm),very heavy precipitation days(RR20mm),severe precipitation days(RR50mm),consecutive wet days(CWD),consecutive dry days(CDD),maximum 5-day precipitation amount(RX5day),and simple daily intensity index(SDII).The future changes were estimated in two time periods for the 21^(st) century(i.e.,near future(NF;2021-2060)and far future(FF;2061-2100))under two Shared Socioeconomic Pathway(SSP)scenarios(SSP2-4.5 and SSP5-8.5).The results suggest increases in the frequency and intensity of extreme precipitation indices under the SSP5-8.5 scenario towards the end of the 21^(st) century(2061-2100).Moreover,from the results of multimodel ensemble means(MMEMs),extreme precipitation indices of RR1mm,RR10mm,RR20mm,CWD,and SDII demonstrate remarkable increases in the FF period under the SSP5-8.5 *** spatial distribution of extreme precipitation indices shows intensification over the eastern part of South Asia compared to the western *** probability density function of extreme precipitation indices suggests a frequent(intense)occurrence of precipitation extremes in the FF period under the SSP5-8.5 scenario,with values up to 35.00 d for RR1mm and 25.00-35.00 d for *** potential impacts of heavy precipitation can pose serious challenges to the study area regarding floodin

关键词： precipitation extremes extreme precipitation indices climate change Coupled Model Intercomparison Project 6(CMIP6) Global Climate Model(GCM) South Asia

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基于ADRV9009的雷达干扰系统设计

电子信息对抗技术 2025年第1期40卷 1-10页

作者：王贤铧孙全常诚余科董阳阳赵成义西安电子科技大学电子工程学院西安710126 南京航空航天大学航天学院南京211106 上海机电工程研究所上海201109 中国电子科技集团公司第二十九研究所成都610036

如何快速高效地实现高灵活性、高集成度、可配置性好、低成本且易于维护的雷达干扰系统是当前雷达对抗领域的研究重点。针对以上需求,采用高集成度宽带射频收发器ADRV9009和FPGA芯片XC7Z100来设计雷达干扰系统,实现从射频到基带的全链... 详细信息

如何快速高效地实现高灵活性、高集成度、可配置性好、低成本且易于维护的雷达干扰系统是当前雷达对抗领域的研究重点。针对以上需求,采用高集成度宽带射频收发器ADRV9009和FPGA芯片XC7Z100来设计雷达干扰系统,实现从射频到基带的全链路信号收发,提高了系统的集成度。通过串口通信对雷达干扰参数进行实时配置,提高了雷达干扰系统的灵活性和可配置性。采用System Generator开发工具对雷达干扰系统进行层次化、模块化设计,缩短了系统开发周期,提高了系统的可维护性。

关键词：高灵活性雷达干扰系统 ADRV9009 FPGA System Generator

自由搜索算法的投影寻踪模型在湿地芦苇调查中的应用

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生态学报 2013年第22期33卷 7204-7210页

作者：李新虎赵成义中国科学院新疆生态与地理研究所乌鲁木齐83001

针对传统湿地芦苇调查统计方法中的问题,建立了自由搜索的投影寻踪模型,将芦苇的生理特征指标和环境因子指标作为投影指标构建了投影指标函数,通过自由搜索算法优化得到最佳投影方向,由最佳投影指标函数来反映各类芦苇的特征,避免了人... 详细信息

针对传统湿地芦苇调查统计方法中的问题,建立了自由搜索的投影寻踪模型,将芦苇的生理特征指标和环境因子指标作为投影指标构建了投影指标函数,通过自由搜索算法优化得到最佳投影方向,由最佳投影指标函数来反映各类芦苇的特征,避免了人为赋予权重的干扰,客观性强,数学概念清晰,并在博斯腾湖芦苇调查统计中进行了应用,结果表明:博斯腾湖芦苇的种类及群落特征没有发生显著的变化,在8个环境因子中水质及水量是影响芦苇产量的主要环境因子,土壤有机质对芦苇产量的影响最小;通过实际应用表明模型应用效果较好,为湿地芦苇资源调查及湿地芦苇的生态保护提供了新的思路。

关键词：投影寻踪自由搜索算法芦苇调查博斯腾湖

基于COMSOL软件的绿洲盐渍化土壤中多离子耦合运移模型构建

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农业工程学报 2018年第15期34卷 100-107页

作者：焦会青盛钰赵成义李保国中国农业大学资源与环境学院农业部华北耕地保育重点实验室国土资源部农用地质量与监控重点实验室北京100193 中国科学院新疆生态与地理研究所乌鲁木齐830011

了解盐分离子在土壤中的迁移规律可以为盐渍土的综合治理以及高效利用提供科学依据,在COMSOL多孔介质和地下水流模块模拟非饱和土壤水流的基础上,自定义偏微分方程组构建盐渍化土壤SO42–、Ca2+、Na+、Cl–、Mg2+耦合运移模型,考虑阳离... 详细信息

了解盐分离子在土壤中的迁移规律可以为盐渍土的综合治理以及高效利用提供科学依据,在COMSOL多孔介质和地下水流模块模拟非饱和土壤水流的基础上,自定义偏微分方程组构建盐渍化土壤SO42–、Ca2+、Na+、Cl–、Mg2+耦合运移模型,考虑阳离子交换过程以及硫酸钙的沉淀溶解反应,并通过新疆绿洲膜下滴灌田间试验对模型进行检验,对比不同活度系数估算方法对模拟结果的影响。结果表明,各离子模拟值与实测值吻合较好,平均相对误差介于9.15%~28.57%,决定系数介于0.41~0.88,该模型能够较好地反映土壤中盐分离子的动态变化规律;在膜下滴灌条件下,膜下0~40 cm土层的盐分离子有不同程度的淋洗,Cl–和Na+的淋洗效果好于Ca2+和SO42–;活度系数的估算对模拟结果的准确性有重要影响,尤其是盐分含量较高时,采用通用的函数关系可能会带来较大的模拟误差。

关键词：土壤灌溉模型盐分离子 COMSOL 离子运移离子反应膜下滴灌

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阿克苏河流域近46年气候变化研究

干旱区资源与环境 2011年第3期25卷 78-83页

作者：孙晓娟赵成义郑金丰塔里木大学水利与建筑工程学院阿拉尔843300 中国科学院新疆生态与地理研究所乌鲁木齐830011

利用线性回归、突变分析和小波分析方法,分析了阿克苏河流域1961-2006年6个地面台站的平均气温和降水量的变化。结果表明:1)46 a来阿克苏河流域气温呈上升趋势,气候倾向率为0.18℃/10 a;2)阿克苏河流域46 a来年降水量以13.1mm/10 a的变... 详细信息

利用线性回归、突变分析和小波分析方法,分析了阿克苏河流域1961-2006年6个地面台站的平均气温和降水量的变化。结果表明:1)46 a来阿克苏河流域气温呈上升趋势,气候倾向率为0.18℃/10 a;2)阿克苏河流域46 a来年降水量以13.1mm/10 a的变化倾向率呈增加趋势;3)阿克苏河流域的年平均气温在1993年发生了由低向高的突变,降水在1987年发生了由低向高的突变;4)阿克苏河流域年降水量较大尺度12-16 a和8-12 a左右的振荡周期非常明显。

关键词：阿克苏河气候变化气温降水突变分析小波分析