Seamless integration of spatial statistics and GIS: The S-PLUS for ArcView and the S+Grassland Links     

Shuming Bao  Luc Anselin  Doug Martin  Diana Stralberg 《Journal of Geographical Systems》2000,2(3):287-306

The extension of the functional capacity of geographic information systems (GIS) with tools for statistical analysis in general and exploratory spatial data analysis (ESDA) in particular has been an increasingly active area of research in recent years. In this paper, two operational implementations that combine the functionality of spatial data analysis software with a GIS are considered more closely. They consist of linkages between the S-PLUS software for data analysis and two different GIS implementations, the ArcView desktop system, which is mostly vector-oriented, and the primarily raster-based Grassland open GIS environment. We emphasize conceptual and technical issues related to the software implementation of these approaches and suggest future directions for linking spatial statistics and GIS. Received: 14 January 1999 / Accepted: 11 May 1999  相似文献   

Low-field magnetic susceptibility: a proxy method of estimating increased pollution of different environmental systems   总被引：18，自引：0，他引：18  

E. Petrovský  A. Kapička  N. Jordanova  M. Knab  V. Hoffmann 《Environmental Geology》2000,39(3-4):312-318

 A need for rapid and inexpensive (proxy) methods of outlining areas exposed to increased pollution by atmospheric particulates of industrial origin caused scientists in various fields to use and validate different non-traditional (or non-chemical) techniques. Among them, soil magnetometry seems to be a suitable tool, at least in some cases. This method is based on the knowledge that ferrimagnetic particles, namely magnetite, are produced from pyrite during combustion of fossil fuel. Besides the combustion processes, magnetic particles can also originate from road traffic, for example, or can be included in various waste-water outlets. Magnetite, Fe₃O₄, ranks among the main ferrimagnetic minerals and its identification in various ecosystems can contribute to fast and simple outlining of areas and sites exposed to higher pollution impact. Here the method of magnetic mapping of anthropogenic pollution will be introduced using a review of our recent case studies on different ecosystems in the Czech Republic and Germany. Received: 20 June 1998 · Accepted: 9 November 1998  相似文献   

Deposition of nanoparticles on school eyeglasses in urban and rural areas:A methodology for a more real assessment of the possible impacts     

Kátia Martinello  James C.Hower  Guilherme L.Dotto  Claudete G.Ramos  Carlos E.Schnorr  Diana Pinto 《地学前缘(英文版)》2022,(1):498-505

Because incomplete confirmation is available concerning the influential role of atmosphere contamination on conjunctivitis,myopia,asthma,and allergic rhinitis in Brazil,the focus of the present work is to explore the possible relations among atmosphere contamination and eye problems.Rather that a case study on eye diseases,by way of questionnaires supplemented by the investigation of nanoparticles(NPs)on eyeglasses,the study examines the mechanisms in which NPs and ultra-fine particles are deposited on the glasses of children up to 10 years of age in urban and rural area.The important connection between atmosphere contaminants and individual protection equipment justifies improving indoor school properties in order could protect children’s eyes,particularly in high-pollution/high-particulate areas.  相似文献   

Mental preparation for climate adaptation: The role of cognition and culture in enhancing adaptive capacity of water management in Kiribati   总被引：3，自引：0，他引：3  

Natasha Kuruppu^{Author Vitae}  Diana LivermanAuthor Vitae 《Global Environmental Change》2011,21(2):657-669

In many Least Developed Countries (LDCs) and Small Island Developing States (SIDS), such as in Kiribati, formal national adaptation programmes are currently being operationalised or are in the pipeline. A key focus is on motivating householders to adapt in anticipation of climate change through pilot community projects. In this paper, we argue that the water sector must pay equal attention to how communities cognitively perceive the process of adaptation if interventions are to be effective. Adopting a cognitive model to gain such insights we conclude that individual's belief in their own abilities to manage water stress play a crucial role in driving intentions to adapt and therefore greater attention needs to be placed on understanding the underling drivers shaping such beliefs.  相似文献   

Strongly magnetic soil developed on a non-magnetic rock basement: A case study from NW Bulgaria     

Hana Grison  Eduard Petrovský  Neli Jordanova  Aleš Kapička 《Studia Geophysica et Geodaetica》2011,55(4):697-716

The enhanced magnetic susceptibility of modern soils is assumed to have several reasons including, e.g., weathering of an iron-rich geological basement, natural fires, bacterial processes and atmospheric deposition of anthropogenic particles. We report on a case where none of the above sources of magnetic enhancement is evident: a modern soil with high magnetic susceptibility over the whole soil profile, developed on nonmagnetic limestones, in an area with no industrial activities. The surface magnetic susceptibility varies from 60 to 110×10⁻⁵ SI, while that of the rock basement is nearly zero. Moreover, significant frequency-dependent magnetic susceptibility (> 12%) suggests that superparamagnetic secondary magnetite/maghemite plays an important role. Possible mechanisms, responsible for this magnetic enhancement, are discussed.  相似文献   

Impact of mining activities on sediments in a semi-arid environment: San Pedro River, Sonora, Mexico     

Agustín Gómez-Álvarez  Jesús L. Valenzuela-García  Diana Meza-Figueroa  Margarita de la O-Villanueva  Jorge Ramírez-Hernández  Javier Almendariz-Tapia  Efrén Pérez-Segura 《Applied Geochemistry》2011,26(12):2101-2112

A study of the San Pedro River (SPR), which is located in a semi-arid region in Sonora, Mexico, was conducted to evaluate the chemical, spatial and temporal (mobilization) trends of potentially harmful metals in its sediment in the rainy and dry seasons. High total concentrations of metals were detected in the following order: Fe > Cu > Mn > Zn > Pb > Cd. All studied metals except for Pb were increased during the dry season showing the effect of climate on the metal distribution in sediments. The results of sequential extraction indicated that the residual and Fe/Mn oxide fractions were the most important with regard to retaining potentially harmful metals in the sediments. In the exchangeable carbonate and Fe oxide fractions, high concentrations of metals were detected, representing high environmental risk. The geoaccumulation index shows slight to moderate contamination in most samples, and sampling point E4 (related to cattle activity) shows strong contamination for Cd, Cu, Pb and Zn. Enrichment factors (EFs) demonstrate anthropogenic origins for Pb (EF: 3–57), Cd (EF: 6–73) and Cu (EF: 1.5–224). This study shows that sediments are impacted by anthropogenic activities related to the mining industry, untreated wastewater discharges from the city of Cananea and cattle activities. Metal mobility in the SPR can disrupt the development of aquatic species in the river.  相似文献   

Ascomycete fungi on dimension stone of the “Burg Gleichen”, Thuringia     

Christine Hallmann  Diana Fritzlar  Lorena Stannek  Michael Hoppert 《Environmental Earth Sciences》2011,63(7-8):1713-1722

In the present study, the diversity of ascomycete fungi was investigated on two wall areas of the “Burg Gleichen”, Thuringia (Germany), made of various types of sandstones, travertine and Grenzdolomit. From a W-exposed, shaded wall area, free-living ascomycetes (mainly “black fungi”) and green algae could be retrieved from sandstone lithologies. Sandstone from an ESE-exposed area was mainly colonized by lichen ascomycetes and the lichen alga Trebouxia. Both areas share a small number of generalist species, related to the ascomycete black fungi Sarcinomyces petricola, Phaeococcomyces chersonesos and Stichococcus mirabilis. Free-living black fungi were isolated and characterized with respect to cell wall morphology and melanin content. A remarkably rigid melanin layer, incorporated in the cell wall of a Cladosporium isolate is presented in detail.  相似文献   

Multicolour Photometry of RX and During 1994/95     

Diana Kjurkchieva  Dragomir Marchev  Waldemar Ogloza 《Astrophysics and Space Science》1997,250(2):261-269

The cataclysmic star RX And was observed in the states standstill and quiescence. They differed not only in the light level but in the type of variations around this level. The standstill observed by us turned out quite near to the maximum light and its duration was unusually long. The energy distribution of RX And at the standstill seemed similar to the spectrum of an accretion disk. Two variabilities with periods 3 h 43 min and 1 h 26 min were found at the standstill but only the second of them was present at quiescence too. The star did not show light variability with the spectroscopic period. We tried to interpret some of the results by the supposition that the Z Cam-stars are an intermediate subtype of the cataclysmic stars evolving from UX UMa-subtype to U Gem-subtype and that probably RX And presents a pattern of Z Cam-star that is very near to the U Gem-subtype.  相似文献   

RING CURRENT DYNAMICS DURING THE 13–18 JULY 2000 STORM PERIOD     

Jordanova  V.K.  Thorne  R.M.  Farrugia  C.J.  Dotan  Y.  Fennell  J.F.  Thomsen  M.F.  Reeves  G.D.  McComas  D.J. 《Solar physics》2001,204(1-2):361-375

We study the development of the terrestrial ring current during the time interval of 13–18 July, 2000, which consisted of two small to moderate geomagnetic storms followed by a great storm with indices Dst=−300 nT and Kp=9. This period of intense geomagnetic activity was caused by three interplanetary coronal mass ejecta (ICME) each driving interplanetary shocks, the last shock being very strong and reaching Earth at ∼ 14 UT on 15 July. We note that (a) the sheath region behind the third shock was characterized by B _z fluctuations of ∼35 nT peak-to-peak amplitude, and (b) the ICME contained a negative to positive B _z variation extending for about 1 day, with a ∼ 6-hour long negative phase and a minimum B _z of about −55 nT. Both of these interplanetary sources caused considerable geomagnetic activity (Kp=8 to 9) despite their disparity as interplanetary triggers. We used our global ring current-atmosphere interaction model with initial and boundary conditions inferred from measurements from the hot plasma instruments on the Polar spacecraft and the geosynchronous Los Alamos satellites, and simulated the time evolution of H⁺, O⁺, and He⁺ ring current ion distributions. We found that the O⁺ content of the ring current increased after each shock and reached maximum values of ∼ 60% near minimum Dst of the great storm. We calculated the growth rate of electromagnetic ion cyclotron waves considering for the first time wave excitation at frequencies below O⁺ gyrofrequency. We found that the wave gain of O⁺ band waves is greater and is located at larger L shells than that of the He⁺ band waves during this storm interval. Isotropic pitch angle distributions indicating strong plasma wave scattering were observed by the imaging proton sensor (IPS) on Polar at the locations of maximum predicted wave gain, in good agreement with model simulations.  相似文献   

Internal structure of massive terrestrial planets     

Diana Valencia  Richard J. O'Connell 《Icarus》2006,181(2):545-554

Planetary formation models predict the existence of massive terrestrial planets and experiments are now being designed that should succeed in discovering them and measuring their masses and radii. We calculate internal structures of planets with one to ten times the mass of the Earth (Super-Earths) to obtain scaling laws for total radius, mantle thickness, core size and average density as a function of mass. We explore different compositions and obtain a scaling law of R∝M0.267-0.272 for Super-Earths. We also study a second family of planets, Super-Mercuries with masses ranging from one mercury-mass to ten mercury-masses with similar composition to the Earth's but with a larger core mass fraction. We explore the effect of surface temperature and core mass fraction on the scaling laws for these planets. The scaling law obtained for the Super-Mercuries is R∝M∼0.3.  相似文献