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1.
A.M.D. van Rotterdam-Los S.P. Vriend M.J. van Bergen P.F.M. van Gaans 《Journal of Geochemical Exploration》2008,96(1):53-68
Acid water from the Banyuputih river (pH 3.5) is used for the irrigation of agricultural land in the Asembagus coastal area (East Java, Indonesia), with harmful consequences for rice yields. The river water has an unusual composition which is caused by seepage from the acidic Kawah Ijen crater lake into the river. This unique irrigation setting allows the study of soil acidification in situ. This paper assesses the effects of volcanogenically contaminated irrigation water on the chemical properties of the agricultural soils.The changes in soil properties were evaluated by comparing samples taken from the topsoil and sub-soil (1–3 m depth) from areas irrigated with acid water and areas irrigated with neutral water. The field survey thus resulted in four soil categories. Bulk soil composition, organic matter content, moisture content and particle size distribution were determined. Reactive phases were quantified with the selective extractions 1 M KCl, 0.1 M Na-pyrophosphate and 0.2 M acid ammonium oxalate (AAO).By comparing the four soil categories it is shown that the use of the naturally polluted irrigation water has had a large influence on the chemical composition of the topsoil. The composition of the soil solution has changed over the entire investigated soil profile. Furthermore the acid irrigation water has strongly modified the composition of the reactive phases, extracted as KCl, pyrophosphate, and AAO extractable elements, and also the bulk soil composition has been significantly modified. Overall this has resulted in the net dissolution of some elements and the net precipitation of others. The changes in the reactive phases and bulk soil composition are only apparent in the topsoil (0–20 cm) but not in the deeper soil. 相似文献
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Wolfgang H. Berger Memorie K. Yasuda Torsten Bickert Gerold Wefer 《International Journal of Earth Sciences》1996,85(3):466-495
We provide a reconstruction of atmospheric CO2 from deep-sea sediments, for the past 625000 years (Milankovitch chron). Our database consists of a Milankovitch template
of sea-level variation in combination with a unique data set for the deep-sea record for Ontong Java plateau in the western
equatorial Pacific. We redate the Vostok ice-core data of Barnola et al. (1987). To make the reconstructions we employ multiple
regression between deep-sea data, on one hand, and ice-core CO2 data in Antarctica, on the other. The patterns of correlation suggest that the main factors controlling atmospheric CO2 can be described as a combination of sea-level state and sea-level change. For best results squared values of state and change
are used. The square-of-sea-level rule agrees with the concept that shelf processes are important modulators of atmospheric
CO2 (e.g., budgets of shelf organic carbon and shelf carbonate, nitrate reduction). The square-of-change rule implies that, on
short timescales, any major disturbance of the system results in a temporary rise in atmospheric CO2. 相似文献
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马春萍 《测绘与空间地理信息》2009,32(4):126-130
着重于网络地图与行业结合的思想,详述了开发过程的思路和所用技术.对网络地图与行业结合的入门有重要意义.尤其对于智能交通、120急救平台等有很好参考价值.应用结果表明,本开发过程对于应急管理是个辅助平台,对决策起着重要的参考价值,为类似的工作可以提供借鉴. 相似文献
6.
基于Android的移动气象信息服务系统设计与实现 总被引:2,自引:0,他引:2
为了丰富移动气象信息服务手段提升服务能力,使用Java,C#,VB,Delphi编程,开发了基于智能终端的移动气象信息服务系统。系统以用户体验为切入点结合智能终端特有的设备特性和移动应用软件特性提供创新型移动气象产品。该系统是一种集气象信息处理、发布和接收为一体的服务系统,用户可以通过该系统随时获取气象信息。介绍了系统的架构设计与客户端设计。详细阐述了采用Java技术在Android平台上研发移动客户端软件过程中所涉及问题的解决方法,包括手势控制、GIS服务、软件管理、系统稳定性和兼容性等问题的解决。 相似文献
7.
Java环境下基于Hibernate的GIS数据库访问策略 总被引:5,自引:0,他引:5
全关系型数据存储模式将GIS数据的空间数据和属性数据统一存储于关系数据库中,分析Java应用程序通过JDBC和SQL语言访问关系数据库中存储的GIS数据的不足,提出基于。Hibernate的解决方案,并给出地理信息共享系统的开发实例。 相似文献
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网络地图平台设计是数字地图应用的一个重要发展方向。作者着重论述了采用Java Applet建立网络地图服务平台的实现思路、基本框架、数据组织及系统实施的关键技术,在此基础上介绍了地图发布软件的基本功能设计、结合COM组件技术实现公交换乘功能设计、界面设计等,最后给出具体实例。 相似文献
10.
Yoshinobu Tsuji Fumihiko Imamura Hideo Matsutomi Costas E. Synolakis Puspito T. Nanang Jumadi Satoshi Harada Se Sub Han Ken'ichi Arai Benjamin Cook 《Pure and Applied Geophysics》1995,144(3-4):839-854
A field survey of the June 3, 1994 East Java earthquake tsunami was conducted within three weeks, and the distributions of the seismic intensities, tsunami heights, and human and house damages were surveyed. The seismic intensities on the south coasts of Java and Bali Islands were small for an earthquake with magnitudeM 7.6. The earthquake caused no land damage. About 40 minutes after the main shock, a huge tsunami attacked the coasts, several villages in East Java Province were damaged severely, and 223 persons perished. At Pancer Village about 70 percent of the houses were swept away and 121 persons were killed by the tsunami. The relationship between tsunami heights and distances from the source shows that the Hatori's tsunami magnitude wasm=3, which seems to be larger for the earthquake magnitude. But we should not consider this an extraordinary event because it was pointed out byHatori (1994) that the magnitudes of tsunamis in the Indonesia-Philippine region generally exceed 1–2 grade larger than those of other regions. 相似文献