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Mathematical Analyses for the influence of Soil Conditions and Nntrient Interactions on Cotton Yields

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Pedosphere 1994年第3期4卷 255-263页

作者： zhang JIANHUI TANG SHIJIA LUO YOUFANG HU CHANGQING and YANGXIAO(Department of Soil Science, {1. of {2. {3. and environment, chinese academy of Sciencesand Ministcy of Water Conseruancy, chengdu 61.O41.(china))(Cotton {1., Si

he influence of soil chemical properties and soil nutrition on cotton yields was studied by means ofestablishing mathematical models. The nultivariate quadratic regression equations developed by a stepwiseregression method not only presented the single effect of soil factors but also displayed the interaction (syn-ergistic or antagonistic) of soil nutrients. The effect of individual factor and the way of nutrient interactionwere further analysed by the path analysis method. The results showed that among major factors affectingcotton yields, there existed the interactions between macronutrients(available P × available K), and betweenmacronutrients and microelements (N×Zn, P×Mo, P×Cu, P × Zn, K×Mo) besides the single effect of soilpH, total P, available Cu and available Zn.

关键词： combined effect cotton yield multivariate quadratic regression path analysis soil nutrient

Possible effect of ENSO on annual sediment discharge of debris flows in the Jiangjia Ravine based on Morlet wavelet transforms

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International Journal of Sediment Research 2008年第3期23卷 267-274页

作者： J. H. zhang1, F. Q. WEI2. S. Z. LIU3. C. GAO41 Dr., Research Scientist, Hainan Meteorological Science institute, South-Sea Meteorology & Disaster Mitigation Research Key Laboratory, Haikou,{2., No. 60 Haifu Road, Haikou,{2., 2.Dr., Research Scientist, 3.Research Scientist,4 Dr.,institute of mountain hazards and environment, CAS, No. 9, Sec. 4, South Renmin Road, chengdu,{2. [a]Dr. Research Scientist Hainan Meteorological Science institute South-Sea Meteorology & Disaster Mitigation Research Key Laboratory Haikou china No. 60 Haifu Road Haikou china [b]Dr. Research Scientist [c]Research Scientist institute of {1. {2. and {3. CAS No. 9 Sec. 4 South Renmin Road chengdu china [d]Dr. Research Scientist institute of {1. {2. and {3. CAS No. 9 Sec. 4 South Renmin Road chengdu china

The multi-time-scale structures of an annual sediment discharge series of debris flow in the Jiangjia Ravine and the Southern Oscillation index are analysed using the method of Morlet wavelet transformations. The possible effects of El Nio episodes on the annual sediment discharge are discussed by comparing the period variations of ENSO and the discharge. The results show that the annual sediment discharge series of debris flow is related to El Nio episodes. Generally, the annual sediment discharge of debris flow is less than usual during an El Nino episode and debris flow is less active. On the contrary, the annual sediment discharge of debris flows is greater than usual during a La Nia episode and debris flows are more frequent. There is a relationship between the annual sediment discharges of debris flow in the Jiangjia Ravine and the summer Southern Oscillation index, with both having quasi-periodic variations of 2.and 5–6 years.

关键词： Debris flow ENSO Wavelet transform Periodic variation

Antecedent snowmelt and orographic precipitation contributions to water supply of Pakistan disastrous floods,2.2.

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Advances in Climate Change Research 2024年第3期15卷 419-430页

作者： Yan WANG Peng CUI Chen-Di zhang Guo-Tao zhang Jian-Sheng HAO Xu {2. Yao-Zhi JIANG Lu WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of mountain {1. and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Polar and Marine Research institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China School of Resources and environment University of Electronic Science and Technology of ChinaChengdu 610054China Hebei Province Tangshan Caofeidian Meteorological Bureau Tangshan 063000China

In 2.{1.,the Pakistan witnessed the hottest spring and wettest summer in *** devastating floods inundated a large portion of Pakistan and caused enormous ***,the primary water source and its contributions to these unprecedented floods remain *** on the reservoir inflow measurements,Multi-Source Weighted-Ensemble Precipitation(MSWEP),the fifth generation ECMWF atmospheric reanalysis(ERA5)products,this study quantified the contributions of monsoon precipitation,antecedent snow-melts,and orographic precipitation enhancement to floods in *** found that the Indus experienced at least four inflow up-rushes,which was mainly supplied by precipitation and snowmelt;In upper Indus,abnormally high temperature continued to influence the whole summer and lead to large amounts of snowmelts which not only was a key water supply to the flood but also provided favorable soil moisture conditions for the latter *** July,the snowmelt has higher contributions than the precipitation to the streamflow of Indus River,with contribution value of more than 60%.Moreover,the snowmelt could still supply 2.%-40%water to the lower Indus in July and August;The leading driver of 2.{1. mega-floods over the southern Pakistan in July and August was dominated by the precipitation,where terrain disturbance induced precipitation account to approximately 3.%over the southern *** results help to understand the mechanisms of flood formation,and to better predict future flood risks over complex terrain regions.

关键词： Extreme heavy rainfall Snowmelt Orographic precipitation Floods Pakistan

Erosion and Sediment Production in Small Watershed in Purple Hilly Areas and Prevention Techniques

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Wuhan University Journal of Natural Sciences 2003年第3B期8卷 1041-1046页

作者： zhang Bao-hua, He Yu-rong, Zhou Hong-yi, Zhu Boinstitute of {2. {3. and environment, chinese academy of Sciences, chengdu 610041, sichuan, china Department of Geography, Liaocheng University, Liaocheng 2.2.59, Shandong, china institute of {1. {2. and {3. Chinese Academy of Sciences Chengdu 610041 SichuanChina Department of Geography Liaocheng UniversityLiaocheng 252059 Shandong China institute of {1. {2. and {3. Chinese Academy of Sciences Chengdu 610041 SichuanChina

Purple Soil distributes extensively and mainly in china. Because of abundant easily weatherable parent rocks/ materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gradients, erosion and sediment production of purple soils are very severe with main fashions of water erosion and gravitational erosion. Basing on observed data in small watersheds, rainfall erosivity, vegetation coverage, previous soil water content, flow and relating factors such as climate, topograph of small watershed, land usage, and soil kinds are all the influence factors of erosion and erodibility of purple soil as well as sediment production and transport in small watershed of purple hilly areas. The effective technological countermeasures of ecosystem restoration, agricultural tillage for water conservation and erosion prevention, agriculture project, and soil changing for fertility and anti-erosion were provided.

关键词： purple soil characteristics of erosion and sediment production) influence factors prevention techniques

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山区生态果园建设对农业小气候的影响

山地学报 2007年第5期25卷 602-607页

作者：张丹陈红高庭艳中国科学院水利部成都山地灾害与环境研究所四川省凉山彝族自治州农业高新技术发展有限公司中国科学院水利部成都山地灾害与环境研究所四川成都610041 中国科学院研究生院北京1.003. 四川西昌61.000

在四川省凉山彝族自治州西昌市海拔1.500 m的半山荒坡地种植系列果树,建设生态果园,观察其气温、空气相对湿度和地温变化。数据分析表明,生态果园建设对微区气候条件有很好的调节作用。气温日较差变小,年平均减小0.7℃,空气相对湿度明... 详细信息

在四川省凉山彝族自治州西昌市海拔1.500 m的半山荒坡地种植系列果树,建设生态果园,观察其气温、空气相对湿度和地温变化。数据分析表明,生态果园建设对微区气候条件有很好的调节作用。气温日较差变小,年平均减小0.7℃,空气相对湿度明显增加,年平均提高1.0},平均地表温度的日较差减小,年平均减小{1.6℃,极端地表高温和极端地表低温有所下降。

关键词：生态果园农业小气候

元胞自动机在模拟土壤侵蚀时空演化过程中的应用

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水土保持研究 2005年第6期12卷 58-60,155页

作者：原立峰周启刚中科院成都山地灾害与环境研究所

土壤侵蚀作为一个全球性的环境问题已经越来越受到人们的广泛关注。动态模拟和预测土壤侵蚀的发育及演化过程具有十分重要的意义。元胞自动机(C e llu lar A u tom ata简称CA)是一种“自下而上”的动态模拟建模框架,具有模拟地理复杂系... 详细信息

土壤侵蚀作为一个全球性的环境问题已经越来越受到人们的广泛关注。动态模拟和预测土壤侵蚀的发育及演化过程具有十分重要的意义。元胞自动机(C e llu lar A u tom ata简称CA)是一种“自下而上”的动态模拟建模框架,具有模拟地理复杂系统时空演化过程的能力。从元胞自动机的概念和原理入手,介绍了CA模型的特征及其在土壤侵蚀学科中的应用情况和存在问题,对CA模型应用于土壤侵蚀过程的模拟、预测的可行性和可操作性进行了探讨。

关键词：元胞自动机复杂性时空模拟地理模型

Impoverishment of Soil Nutrients in Gully Erosion Areas in yuanmou Basin

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Wuhan University Journal of Natural Sciences 2003年第3B期8卷 1034-1040页

作者： zhang Jian-guo, Li Hui-xia, He Xiao-rong, Sheng Xin-ju, Fan Jian-rong, Zhu Bo{1. of {2. {3. and environment, chinese academy of Sciences, chengdu 610041, sichuan, china institute of {1. {2. and {3. Chinese Academy of Sciences Chengdu 610041 SichuanChina

The impoverishment of soil nutrients of nine gully head areas in yuanmou Basin is assessed through an integrated evaluation method established on the basis of Fuzzy mathematics and multivariate mathematical theory. Results show that soil erosion of gully erosion area in yuanmou basin has resulted in severe impoverishment of soil nutrients. All gully head areas are at high leves of impoverishment except for one at middle. By probing into and analyzing the mechanism of impoverishment of soil nutrients, we find that soil erosion has led to impoverishment of soil nutrients in a way of compacting soil, heightening position of obstacle horizon, and reducing the content of organic matter, as well as the direct loss of nutrient elements. Finally, this paper points out that soil and water conservation arming at the prevention of soil erosion is the most effective way against impoverishment of soil nutrients in yuanmou basin.

关键词： dry red soil soil erosion soil nutrients impoverishment integrated evaluation

四川盆地紫色丘陵区土地利用类型对土壤理化性质的影响

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山地学报 2005年第2期23卷 209-212页

作者：刘刚才范建容张建辉高美荣王道杰西南农业大学资源与环境学院中国科学院水利部成都山地灾害与环境研究所中国科学院水利部成都山地灾害与环境研究所中国科学院水利部成都山地灾害与环境研究所中国科学院水利部成都山地灾害与环境研究所重庆400716 中国科学院水利部成都山地灾害与环境研究所四川成都610041 四川成都610041四川成都610041四川成都610041四川成都610041

为了提供土地利用结构调整的科学依据,调查和测试了四川盆地紫色丘陵区南充和盐亭两个典型小流域内草地、林地和耕地的土壤理化性质,结果表明:不同土地利用对土壤理化性质的影响是明显的。林/草地较耕地能显著增加(约1.)土壤有机质含... 详细信息

为了提供土地利用结构调整的科学依据,调查和测试了四川盆地紫色丘陵区南充和盐亭两个典型小流域内草地、林地和耕地的土壤理化性质,结果表明:不同土地利用对土壤理化性质的影响是明显的。林/草地较耕地能显著增加(约1.)土壤有机质含量。研究结果还揭示了耕地的长期耕种,使其土壤理化性质和功能退化,如土壤抗蚀性和持水性能降低。因此,增加耕地的有机肥投入是耕地可持续发展的重要举措

关键词：土地利用土壤性质土壤退化耕地

Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science china Earth Sciences 2024年第5期67卷 1529-1544页

作者： Chuan yuan Xiaoping YUE Yafeng {1. Yu {1. Yanting HU Qiang TANG Li GUO Shuai WANG Xingwu DUAN Wenhua XIANG Xiaohua WEI Xiaoyan LI College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Hydraulics and mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China Department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community *** advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely *** address this gap,we conducted a systematic review of 1.2. papers published between{1.00 and{1.2.,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2.),Mg^(2.),NH_(4)^(+),Cl^(-),NO_(3.^(-)and SO_(4)^(2.))from the Web of Science and {2. Knowledge Infrastructure *** aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and *** results of this study indicate that stemflow exhibits,on average,2.1.imes greater ion concentration(6.1.6}mg L^(-1.)compared to *** particular,among the investigated ions,SO_(4)^(2.)(1.0}45and 6.3.0}mg L^(-1.)for stemflow and throughfall,respectively,and Cl^(-)(9.2. and 4.81.mg L^(-1.)exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(1.6}7 and 5.8)and Mg^(2.)(5.6 and{1.8)have the highest enrichment *** climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid *** the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing *** addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1.to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural *** findings emphasize the need for increased attentions to artificial ecosystems,such as urban

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones