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吉林省德惠市土壤速效钾的空间分异及不同插值方法的比较

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水土保持学报 2004年第4期18卷 97-100页

作者：李晓燕张树文中国科学院东北地理与农业生态研究所

基于地统计学和地理信息系统,采用区变量的半变异理论定量研究了土壤速效钾的空间变异特征,分析比较了不同空间插值方法的插值精度,并利用最优Kriging法插值生成了研究区土壤速效钾的分布格局图。结果表明:研究区土壤速效钾具有中等强... 详细信息

基于地统计学和地理信息系统,采用区变量的半变异理论定量研究了土壤速效钾的空间变异特征,分析比较了不同空间插值方法的插值精度,并利用最优Kriging法插值生成了研究区土壤速效钾的分布格局图。结果表明:研究区土壤速效钾具有中等强度的空间自相关,步长为108.5km;块金效应显著,C0/sill值为0.43。所有插值方法中,球面多项式插值的RMSE最大,平常克吕格的指数模型插值精度最高。IDW虽然也常常被用来进行土壤属性特征的插值分析,但它只与距离有关,对于区域性的较大差异或存在多因子影响时,Kriging方法有其明显的优势;土壤速效钾的分布以中部饮马河为线,东西差异较大,总体自东北向西南呈有规律地逐渐增大的趋势。

关键词：吉林德惠市土壤速效钾空间分异插值方法

矿山泥石流成灾度模糊综合评价——以神府东胜矿区为例

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山地学报 2002年第2期20卷 212-217页

作者：张丽萍唐克丽浙江大学环境与资源系中国科学院水土保持研究所浙江杭州31002. 陕西杨陵712.00

在神府东胜矿区 ,以矿山泥石流成灾的人为特殊性为基础 ,经济区位影响为目的 ,选择泥石流形成和成灾的自然、经济区位、人为三个方面的 9个因子 ,43条矿山泥石流样沟 ,应用运筹学原理 ,将层次分析与模糊信息推断相结合 ,进行了成灾程度... 详细信息

在神府东胜矿区 ,以矿山泥石流成灾的人为特殊性为基础 ,经济区位影响为目的 ,选择泥石流形成和成灾的自然、经济区位、人为三个方面的 9个因子 ,43条矿山泥石流样沟 ,应用运筹学原理 ,将层次分析与模糊信息推断相结合 ,进行了成灾程度分析。结果显示 :5 0 %以上的泥石流沟属于强成灾范围

关键词：矿山泥石流成灾程度神府东胜矿区运筹学综合评价

Advances in carbon flux observation and research in Asia

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Science china Earth sciences 2005年第Z1期48卷 1-16页

作者： YU Guirui, zhang Leiming, SUN Xiaomin, FU Yuling & li Zhengquan Synthesis Center of chinese Ecosystem Research Network (CERN), {2. of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china Graduate School of the chinese academy of sciences, Beijing 100039, china Synthesis Center of chinese Ecosystem Research Network CERN Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Synthesis Center of chinese Ecosystem Research Network (CERN) Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China

As an important component of FLUXNET, Asia is increasingly becoming the hotspot in global carbon research for its vast territory, complex climate type and vegetation diversity. The present three regional flux observation networks in Asia (i.e. AsiaFlux, KoFlux and chinaFLUX)have 54 flux observation sites altogether, covering tropic rainforest, evergreen broad-leaved forest, broad-leaved and coniferous mixed forest, shrubland, grassland, alpine meadow and cropland ecosystems with a latitudinal distribution from 2.N to 63°N. Long-term and continuous fluxes of carbon dioxide, {2. vapor and energy between the biosphere and atmosphere are mainly measured with eddy covariance technique to (1) quantify and compare the carbon, {2. and energy budgets across diverse ecosystems; (2. quantify the environmental and biotic controlling mechanism on ecosystem carbon, {2. and energy fluxes; (3) validate the soil-vegetation-atmosphere model; and (4) serve the integrated study of terrestrial ecosystem carbon and {2. cycle. Over the last decades, great advancements have been made in the theory and technology of flux measurement, ecosystem flux patterns, simulation and scale conversion by Asian flux community. The establishment of chinaFLUX has greatly filled the gap of flux observation and research in Eurasia. To further promote the flux measurement and research,accelerate data sharing and improve the data quality, it is necessary to present a methodological system of flux estimation and evaluation over complex terrain and to develop the integrated research that combines the flux measurement, stable isotope measurement, remote sensing observation and GIS technique. It also requires the establishment of the Joint Committee of Asian Flux Network in the Asia-Pacific region in order to promote the cooperation and communication of ideas and data by supporting project scientists, workshops and visiting scientists.

关键词： terrestrial ecosystem, flux observation and research, carbon flux, eddy covariance, Asia.

Development of a novel critical nitrogen concentration-cumulative transpiration curve for optimizing nitrogen management under varying irrigation conditions in winter wheat

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The Crop Journal 2024年第4期12卷 1242-1251页

作者： Tianyang Ye Yu zhang Jingyan Xuan Xintian Wang Yang li Junhao Xu liujun Xiao Leilei liu liang Tang Weixing Cao Bing liu Yan Zhu National Engineering and Technology Center for Information Agriculture Engineering Research Center of Smart AgricultureMinistry of EducationKey Laboratory for Crop System Analysis and Decision MakingMinistry of AgricultureJiangsu Key Laboratory for Information AgricultureJiangsu Collaborative Innovation Center for Modern Crop ProductionNanjing Agricultural UniversityNanjing 210095JiangsuChina institute of Remote Sensing and Digital Agriculture Sichuan Academy of Agricultural SciencesChengdu 610066SichuanChina

Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop *** widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop water *** three-year field experiments with winter wheat,encompassing two irrigation levels(rainfed and irrigation at jointing and anthesis)and three N levels(0,180,and 2.0 kg ha1),this study aims to establish a novel approach for determining the Nc dilution curve based on crop cumulative transpiration(T),providing a comprehensive analysis of the interaction between N and water *** Nc curves derived from both crop dry matter(DM)and T demonstrated N concentration dilution under different conditions with different *** equation Nc=6.43T0.2. established a consistent relationship across varying irrigation *** test results indicated that the nitrogen nutrition index(NNI),calculated from this curve,effectively identifies and quantifies the two sources of N deficiency:insufficient N supply in the {2. and insufficient {2. water concentration leading to decreased N availability for root ***,the NNI calculated from the Nc-DM and Nc-T curves exhibited a strong negative correlation with accumulated N deficit(Nand)and a positive correlation with relative grain yield(RGY).The NNI derived from the Nc-T curve outperformed the NNI derived from the Nc-DM curve concerning its relationship with Nand and RGY,as indicated by larger R2.values and smaller *** novel Nc curve based on T serves as an effective diagnostic tool for assessing winter wheat N status,predicting grain yield,and optimizing N fertilizer management across varying irrigation *** findings would provide new insights and methods to improve the simulations of water-N interaction relationship in crop growth models.

关键词： Crop dry matter Crop cumulative transpiration Bayesian statistical model Critical nitrogen dilution curve Nitrogen nutrition index

STUDIES ON ION BEAM APPliCATION TO IMPROVE AQUATIC MACROPHYTE REMEDIATION CAPACITY IN EUTROPHIC waterS

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水生生物学报 2006年第6期30卷 711-717页

作者： li Miao1, WU Yue-Jin 1, zhang Jun 1, YU Han-Qing 2. WU Xiao-Lei 3 and YU Zeng-liang 1 (1. Key Laboratory of Ion Beam Bioengineering, institute of Plasma Physics, the{2., Hefei, china 2.0031 2. School of Chemistry and Material Science, the University of Science and Technology of china, Hefei, china 2.002. 3. Department of Environmental Science and Engineering, Tsinghua University, Beijing, china 100084 ) institute of Plasma Physics the Chinese Academy of Sciences Key Laboratory of Ion Beam Bioengineering CAS Hefei 230031 School of Chemistry and Material Science the University of Science and Technology of China Hefei 230026 Department of Environmental Science and Engineering Tsinghua University Beijing 100084

Using ion beam biotechnology in combination with soil-less plant cultivation on artificial substratum (floating beds), the experiments were conducted with Ipomoea aquatica Forsk. Plants were attached to floating-beds which were placed on the surface of artificially nutrient-enriched tank water, in order to study the purification and remediation efficiency of ion beam-treated I. aquatica cultivars. The results show that N + ion beams with 2.keV energy and dosages of 0, 2.6, 3.9, 5.2. 6.5, 7.8, 9.1×10 13N +(ions)/cm 2.affected I. aquatica dry seeds differently, with the dose of 3.9×10 13N + (ions)/cm 2.improving effectively the performance as expressed by various biological indices. After ion beam app{2.cation, I. aquatica cultivars grew well in nutrient-enriched water bodies, increasing the growth of leaves and stem, number of leaves, length and area of roots, plant height, and weight more remarkably than observed in the control. The net removing rates of TN, TP were as high as 75% and 82., respectively. Especially under the dose of 3.9×10 13N +(ions)/cm 2. the net removing rates of TN, TP were highest, for 77% and 85%, respectively. It was proved that ion beam app{2.cation improves phytoremediation and may be used to purify nutrient rich water bodies.

关键词： Ion beam treatment Aquatic macrophyte Ipomoea aquatica Forsk Nutrient-enriched waters Remediation capacity

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水土流失研究中尺度效应及其机理分析

水土保持学报 2003年第2期17卷 167-169,180页

作者：王飞李锐杨勤科张晓萍中国科学院水利部水土保持研究所西北农林科技大学陕西杨陵712100

空间尺度的大小对水土流失研究影响很大,尺度效应是地理分异规律和地理综合规律在时间和空间上的表现。随着尺度变大,研究对象内的综合性、概括性增强,研究对象之间的主导分异因子级别提高;随着尺度变小,研究对象内的分异性、多样性增强... 详细信息

空间尺度的大小对水土流失研究影响很大,尺度效应是地理分异规律和地理综合规律在时间和空间上的表现。随着尺度变大,研究对象内的综合性、概括性增强,研究对象之间的主导分异因子级别提高;随着尺度变小,研究对象内的分异性、多样性增强,研究对象之间的主导分异因子级别降低。在尺度变化的同时,水土流失规律、主要影响因子、评价方法等同时发生变化。水土流失研究的尺度效应,对水土流失与泥沙资料扩展应用,以及提高流域/区域等较大尺度水土流失量的评价与预测精度等尺度转换问题研究有重要意义。

关键词：水土流失尺度效应尺度转换机理分析

Energy balance closure at chinaFLUX sites

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Science china Earth sciences 2005年第Z1期48卷 51-62页

作者： li Zhengquan, YU Guirui, WEN Xuefa, zhang Leiming, REN Chuanyou & FU Yuling chinese Ecosystem Research Network Synthesis Research Center, {2. of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china Graduate School of the chinese academy of sciences, Beijing 100039, china chinese Ecosystem Research Network Synthesis Research Center Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China chinese Ecosystem Research Network Synthesis Research Center Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Network of eddy covariance observation is measuring long-term carbon and water fluxes in contrasting ecosystems and climates. As one important reference of independently evaluating scalar flux estimates from eddy covariance, energy balance closure is used widely in study of carbon and water fluxes. Energy balance closure in{2.FLUX was evaluated by statistical regression of turbulent energy fluxes (sensible and latent heat) against available energy (net radiation, soil heat flux, canopy heat storage) and the energy balance ratio (EBR) and the frequency distribution of relative errors of energy balance (S). The trends of diurnal and seasonal variation of energy balance in{2.FLUX were analyzed. The results indicated that the imbalance was prevalent in all observation sites, but there were little differences among sites because of the properties variation of sites. The imbalance was greater during nocturnal periods than daytime and closure was improved with friction velocity intensifying. Generally the results suggested that estimates of the scalar turbulent fluxes of sensible and latent heat were underestimated and/or that available energy was overestimated. Finally, we discussed certain factors that are contributed to the imbalance of energy, such as systematic errors associated with the sampling mismatch, systematic instrument bias, neglected energy sinks, low and high frequency loss of turbulent fluxes and advection of heat and water vapor.

关键词： energy balance, chinaFLUX, eddy covariance technique.

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玛纳斯河流域山前平原区地下水系统模型研究

水动力学研究与进展（A辑） 2005年第5期20卷 648-653页

作者：高佩玲雷廷武张石峰李茜山东理工大学资源与环境工程学院山东淄博255049 中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室

新疆干旱少雨,冰川融水季节性较强,要满足工、农业的快速、持续发展,需合理有效地开采、利用地下水资源。玛纳斯河流域周边地区经济发展较快,以灌溉为主的农业生产及工业发展更离不开水资源的供给。本文分析了玛纳斯河流域平原区地下水... 详细信息

新疆干旱少雨,冰川融水季节性较强,要满足工、农业的快速、持续发展,需合理有效地开采、利用地下水资源。玛纳斯河流域周边地区经济发展较快,以灌溉为主的农业生产及工业发展更离不开水资源的供给。本文分析了玛纳斯河流域平原区地下水资源赋存特点,依据开采区含水层水文地质特征,在对研究区边界及初始条件进行合理概化基础上建立了地下水系统模拟模型。考虑到地下水资源动态变化受人工开采型、水文-人工开采型、气候型等混合形式影响的特点,将水资源补给、排泄项划分到7个时段,研究区划分为62.个单元和339个结点,采用有限元方法对模型进行数值离散,在边界条件及垂向水交换量进行动态模拟基础上对潜水和承压水非稳定流动态流场进行了拟合,拟合结果中误差小于0.5m的结点数超过总结点数的85%。得到了该区地下水系统水文地质参数,实现了地下水开采较大的冲洪积扇区较高精度的水资源动态模拟,同时为水资源变化预报预测提供了可靠参数及模型基础。

关键词：地下水资源冲洪积扇动态模拟有限元方法模拟模型

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在降雨侵蚀中黄土地面坡度变化的高分辨研究

山地学报 2005年第5期23卷 79-85页

作者：王春汤国安张婷李占斌王雷吴良超南京师范大学地理信息科学江苏省重点实验室中国科学院水利部水土保持研究所西北大学城市与资源学系西北大学城市与资源学系江苏南京2.0097 陕西杨陵712.00 陕西西安710069

运用近景数字摄影测量方法,获得在不同人工降雨时段黄土模拟小流域高精度、高分辨率的DEM数据,并以地面坡度及其组合形态的变化为切入点,通过对比分析和理论验证,探讨黄土小流域降雨侵蚀过程中地面坡度变化特征,在更宏观空间尺度和高分... 详细信息

运用近景数字摄影测量方法,获得在不同人工降雨时段黄土模拟小流域高精度、高分辨率的DEM数据,并以地面坡度及其组合形态的变化为切入点,通过对比分析和理论验证,探讨黄土小流域降雨侵蚀过程中地面坡度变化特征,在更宏观空间尺度和高分辨的时间尺度上,揭示黄土地貌形成与发育特征。研究结果表明:1)在较好地维持黄土的土壤结构与抗蚀特征,较真实地模拟自然降雨的条件下,模拟流域地面的变化能很好地反映自然地面的发育进程。2.在降雨侵蚀过程中,黄土小流域地面坡度呈现持续性变化规律,平均坡度在地貌发育幼年期呈加速增长趋势,到了壮年期增长幅度呈递减性变化;坡度组合以侵蚀临界角度为轴点呈持续逆转变化,侵蚀临界坡度单元所占面积基本保持稳定。3)黄土地面坡度的变化,一方面受地表物质被侵蚀和迁移程度的影响,另一方面,也是沟间地、沟坡地和沟底地空间面积重新分配的结果。

关键词：黄土侵蚀小流域坡度 DEM