Impact of acid effluent from Kawah Ijen crater lake on irrigated agricultural soils: Soil chemical processes and plant uptake     

A.M.D. van Rotterdam-Los  A. Heikens  S.P. Vriend  M.J. van Bergen  P.F.M. van Gaans 《Journal of Volcanology and Geothermal Research》2008

Volcanogenic contamination of irrigation water, caused by effluent from the hyperacid Ijen crater lake, has severely affected the properties of agricultural soils in East Java, Indonesia. From a comparison of acidified topsoil with subsoil and with top- and subsoil in a reference area, we identified processes responsible for changes in soil and soil solution chemistry induced by acid irrigation water, with emphasis on the nutrients Ca, Mg, Fe, and Mn, and on Al, which may become phytotoxic under acid conditions in soils. Compositional data for bulk soil composition and selective extractions with 1 M KCl and 0.2 M acid ammonium oxalate are used in a mass balance approach to specify element fluxes, including uptake by rice plants. The results show that input via irrigation water has produced an increase in the total aluminum content in the affected topsoil, which is of the same order of magnitude as the increase in labile Al. High bioavailability of Al, as reflected by concentrations in KCl extracts, is consistent with elevated concentrations observed in rice plants. In contrast, and despite the high input via irrigation water, Ca and Mg concentrations have decreased in all measured soil fractions through dissolution of amorphous phases and minerals, and through competition of Al for adsorption sites on the exchange complex and plant roots. Strong leaching is also evident for Fe and especially Mn. In terms of the overall mass balance of the topsoil, plant uptake of Al, Ca, Fe, Mg and Mn is negligible. If the use of acid irrigation would be stopped and the soil pH were to increase to values above 4.5, the observed phytotoxicity of Al will be halted. However, crops may then become fully dependent on the input from irrigation water or fertilizer for essential elements, due to the previous removal from the topsoil through leaching.  相似文献   

数据库连接池的构建及在JSP中的应用     

周世勇  和晓军 《成都信息工程学院学报》2004,19(1):66-71

分析了几种通过JDBC连接数据库的方法,说明使用数据库连接池的优越性,比较数据库连接池与传统的数据库连接的区别,同时实现了一个数据库连接池的创建以及对这个连接池的使用.  相似文献   

基于Java的审批流程管理设计及实现   总被引：2，自引：1，他引：1  

舒红平  舒灿  蒋建民 《成都信息工程学院学报》2004,19(1):12-17

设计了两种审批流程的设定、申请、审批及归档等功能模块.在Java开发平台上,利用组件技术实现了两种审批流程的管理.  相似文献   

浅析C#和Java的细微差别     

徐家良 《成都信息工程学院学报》2004,19(3):422-429

C#是微软推出的新一代程序语言.对C#与Java的一些容易被忽视的细微的差别进行了讨论.C#设计非常精巧,它的编译器能检查出代码设计过程中一些潜在的错误;而这一点,其它的程序语言要用静态分析工具才能实现.这样程序员就可以专注于设计代码,而不必浪费很多时间来调试难以发现的程序语言陷阱,从而节约了调试时间,缩短了开发周期;同时也提出了在Java中的相应解决方法.相信在不久的将来,新版的Java也可能会增进这些新特性.  相似文献   

网络GIS及其实现方式   总被引：11，自引：0，他引：11  

边馥苓  朱国宾 《测绘工程》1998,7(4):1-6

根据不同的网络体系－局域网、Ｉｎｔｅｒｎｅｔ（ＷＥＢ）网,分别介绍了ＧＩＳ的实现方式以及各自的特点和功能的差异。特别阐述了Ｉｎｔｅｒｎｅｔ（ＷＥＢ）ＧＩＳ的三种实现手段－ＣＧＩ方式、Ｊａｖａ方式及ＣＯＭ／ＤＣＯＭ模型和各自的优缺点。在总结三种网络ＧＩＳ特点后,文章分析指出：ＧＩＳ网络实现方式的不同,从本质上讲是由于其功用不同形成的。  相似文献   

基于SuperWaba平台的SVG地图显示技术     

陈建斌  朱宝山  韩文娟 《测绘工程》2009,18(2):63-65

在移动GIS的客户端解决方案中，目前有很多系统采用JavaME＋SVG技术来解决地图显示，取得较好的效果。但由于在WindowsCE上还没有通用的Java虚拟机，上述移动客户端解决方案存在一定的局限性。介绍一个可以运行于WindowsCE、PalmOS、SymbianOS等嵌入式环境下的一个类Java虚拟机SuperWaba，对基于该平台的SVG地图显示技术作初步探讨，解决移动GIS客户端的跨平台问题。  相似文献   

基于Java3D的三维景观网络发布   总被引：3，自引：2，他引：1  

田茂义  张燕  卢秀山  徐文锦  刘峰 《测绘科学》2006,31(4):115-116,125

论文提出了基于J2EE三层体系构架,浏览器/服务器(B/S)结构模式的三维景观W eb发布系统模型。该模型综合利用了App le、tJSP、Servle、tJava3D、BC4 J技术,其基本思路是:利用Java3D三维图形库开发植入JSP的App let插件用于三维景观的显示与交互,通过BC4 J、代理服务器技术实现App let与O rac le数据库服务器之间的数据通讯。实验结果证明了这种结构模型具有一定的优越性。  相似文献   

Characteristics and variability of the Indonesian throughflow water at the outflow straits   总被引：1，自引：0，他引：1  

Agus Atmadipoera  Robert Molcard  Gurvan Madec  Susan Wijffels  Janet Sprintall  Ariane Koch-Larrouy  Indra Jaya  Agus Supangat 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(11):1942-1954

Property structure and variability of the Indonesian Throughflow Water in the major outflow straits (Lombok, Ombai and Timor) are revised from newly available data sets and output from a numerical model. Emphasis is put on the upper layers of the Indonesian Throughflow that impacts the heat and freshwater fluxes of the South Equatorial Current in the Indian Ocean. During the April–June monsoon transition the salinity maximum signature of the North Pacific thermocline water is strongly attenuated. This freshening of the thermocline layer is more intense in Ombai and is related to the supply of fresh near-surface Java Sea water that is drawn eastward by surface monsoon currents and subject to strong diapycnal mixing. The freshwater exits to the Indian Ocean first through Lombok Strait and later through Ombai and Timor, with an advective phase lag of between one and five months. Because of these phase lags, the fresher surface and thermocline water is found in the southeast Indian Ocean from the beginning of the monsoon transition period in April through until the end of the southeast monsoon in September, a much longer time period than previously estimated.  相似文献   

Design and elementary realization of the Vision Earth System     

Yunliang YU Shixiang LIU Narenna WU Xudong ZHANG 《东北亚地学研究》2007,10(1):59-64

The Vision Earth System is a interactive system by employing B/S model.The system has the function of query display and mutually displays relevant geologic information,integrating image information of one outcrop and realizing 3D geologic visualization.In this system,the basis is effective store,transmitting,display and quick query of enormous images and their properties data.From Java technology,this essay researches the elementary realization of Vision Earth System by adopting store formality of enormous images database,quick display image of website and quick image storage method.  相似文献   

功耗分析平台中混合编程的应用研究     

孙敦灿  陈运  万武南  索望 《成都信息工程学院学报》2011,(4):127-131

功耗分析平台是有效实施功耗分析攻击的工具,需要服务器与示波器等多种外设进行通信,同时还需要处理大量高维数组并且要求有良好的可操作性,如果采用单一编程语言来开发,则存在功耗分析攻击效率较低的问题。针对该问题,提出了一种新的解决方法,将Java、C＋＋和Matlab这3种编程语言结合,在功耗波形采集、波形特征处理等方面采用混合编程技术进行开发,充分发挥这3种编程语言各自的优势。实验结果表明,在保证功耗分析攻击准确率的基础上,攻击的效率比采用单一语言编程时提高了30％以上。  相似文献