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Virtual globes have been developed to showcase different types of data combining a digital elevation model and basemaps of high resolution satellite imagery. Hence, they became a standard to share spatial data and information, although they suffer from a lack of toolboxes dedicated to the formatting of large geoscientific dataset. From this perspective, we developed Geolokit: a free and lightweight software that allows geoscientists – and every scientist working with spatial data – to import their data (e.g., sample collections, structural geology, cross-sections, field pictures, georeferenced maps), to handle and to transcribe them to Keyhole Markup Language (KML) files. KML files are then automatically opened in the Google Earth virtual globe and the spatial data accessed and shared. Geolokit comes with a large number of dedicated tools that can process and display: (i) multi-points data, (ii) scattered data interpolations, (iii) structural geology features in 2D and 3D, (iv) rose diagrams, stereonets and dip-plunge polar histograms, (v) cross-sections and oriented rasters, (vi) georeferenced field pictures, (vii) georeferenced maps and projected gridding.Therefore, together with Geolokit, Google Earth becomes not only a powerful georeferenced data viewer but also a stand-alone work platform. The toolbox (available online at http://www.geolokit.org) is written in Python, a high-level, cross-platform programming language and is accessible through a graphical user interface, designed to run in parallel with Google Earth, through a workflow that requires no additional third party software. Geolokit features are demonstrated in this paper using typical datasets gathered from two case studies illustrating its applicability at multiple scales of investigation: a petro-structural investigation of the Ile d’Yeu orthogneissic unit (Western France) and data collection of the Mariana oceanic subduction zone (Western Pacific). 相似文献
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R. S. Reddy D. Goosen G. W. W. Elbersen 《Journal of the Indian Society of Remote Sensing》1985,13(2):1-11
A methodology for the preparation of semi detailed soil maps using medium scale aerial photographs for an area of about 3600 ha in Merida area, Spain is presented. The new concepts such as ‘Basic Land Units’, ‘Soil Consociation’ and ‘Soil Set’ developed by Elbersen (1976) were adopted for this study to see their utility for the preparation of semidetailed soil maps which can be used for land evaluation, land classification and also for making prodictions about the feasibility of a particular project for rural development plannning purposes. Basic land units and their subdivisions like major and minor compo-nents were used for the delineation of interpretation units. Mapping units, viz, Soil Consoication, Soil Complex and miscellaneous land type were used for mapping soils. Soils were classified upto family level and shown as subgroups in the 1:50,000 scale soil map. Soils were mapped as soil sets per basic land unit per subgroup. A model legend for use in the preparation of seimdetailed physiographic cum soil maps is given which is in terms of physiography and Soil Taxonomy qualified by soil sets. 相似文献
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Soil maps have been prepared hitherto by conventional ground surveys and by using aerial photographs. In this paper, the use of LANDSAT data for preparation of small scale soil maps upto association of sub-group level has been discussed. Typical spectral curves for various soils and landuse categories were given based on the mean spectral levels for each LANDSAT band obtained from Multispectral Data Analysis System (M-DAS). Soil characterization using the multispectral data could be done by both image oriented and numerically oriented approaches. The small scale soil maps thus prepared by using the satellite data could be used for regional planning and as map base for further detailed surveys. 相似文献
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Many of the processes involved in soil erosion have dimensions on the millimetre scale. Modelling and quantification of such processes require information on soil surface topography with adequate resolution. The purpose of this study was to generate digital elevation models (DEMs) from soil surfaces with high spatial and temporal resolution. Digital photogrammetry was applied for measuring erosion rates on complex-shaped soil surfaces under laboratory rainfall conditions. A total of 60 DEMs were generated, covering a planimetric area of 16 m2 . The DEMs had a grid resolution of 3 mm. A vertical precision of approximately 1 mm was desired for DEM analysis. A consumer-grade digital camera was used for image acquisition. The camera was calibrated using BLUH software. Homologous points in overlapping images were identified with least squares matching software. Irregularly spaced object coordinates were interpolated to a regular grid in a geographic information system. The resulting DEMs represented the soil surface well. A precision of 1·26 mm in the vertical was attained. The precision of DEM production was limited to camera calibration. Improvements of the setup presented could include the use of better control points and more advanced image matching strategies for identification of homologous points. The DEMs allowed for detailed analysis of soil surface evolution. 相似文献
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M. L. Manchanda Jitendra Prasad H. S. Iyer S. K. Deb R. Pathak 《Journal of the Indian Society of Remote Sensing》1984,12(1):7-18
Soil and Soil Conservation surveys for watershed management were conducted using aerial photos of 1:60,000 scale in parts of North Cachar and Karbi-Anglong districts of Assam. The area was divided into different river catchments and sub-watersheds. The erosion, slope, landuse and soils in relation to physiogrphy were studied in each sub-watershed. The different physiographic units identified in the area were high, medium, low and very low hills; pediplains; alluvial plain and the valleys. These units were further subdivided based on slope, landuse and erosion etc. The soils were classified according to Soil Taxonomy. For priority determination, weightage was alloted to each of the sub-watersheds considering their physiography, slope, landuse, erosion,soil texture, depth and delivery ratio and sediment yield was calculated for each subwatershed. It has been found that out of 122875 ha, an area of 1745 ha had very high priority, 30590 ha high, 37290 ha medium, 51957 ha low and 1294 ha very low priority for soil conservation purposes. 相似文献
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Ian D. Bishop Mike Barry Elsworth McPherson Joiana Nascarella Karen Urquhart & Francisco Escobar 《Transactions in GIS》2002,6(3):311-326
Informal settlements are a chronic issue in developing countries. Management and formalisation processes require good spatial data and analytical tools. While software such as geographic information systems (GIS) are widely available, access to good data and skilled users may be limited. In this paper we suggest that digital multimedia learning tools, accessible via the World Wide Web (WWW) may be part of the solution. We present the rationale for, and structure of, a suite of prototype learning modules for neighbourhood operations. We illustrate the use of these operations by converting shack locations into population density maps for the Imizamo Yethu settlement near Cape Town, South Africa. This prototype forms a part of a larger web site that also includes background information, data sources and software. 相似文献
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A seamless vegetation type map of India (scale 1: 50,000) prepared using medium-resolution IRS LISS-III images is presented. The map was created using an on-screen visual interpretation technique and has an accuracy of 90%, as assessed using 15,565 ground control points. India has hitherto been using potential vegetation/forest type map prepared by Champion and Seth in 1968. We characterized and mapped further the vegetation type distribution in the country in terms of occurrence and distribution, area occupancy, percentage of protected area (PA) covered by each vegetation type, range of elevation, mean annual temperature and precipitation over the past 100 years. A remote sensing-amenable hierarchical classification scheme that accommodates natural and semi-natural systems was conceptualized, and the natural vegetation was classified into forests, scrub/shrub lands and grasslands on the basis of extent of vegetation cover. We discuss the distribution and potential utility of the vegetation type map in a broad range of ecological, climatic and conservation applications from global, national and local perspectives. We used 15,565 ground control points to assess the accuracy of products available globally (i.e., GlobCover, Holdridge’s life zone map and potential natural vegetation (PNV) maps). Hence we recommend that the map prepared herein be used widely. This vegetation type map is the most comprehensive one developed for India so far. It was prepared using 23.5 m seasonal satellite remote sensing data, field samples and information relating to the biogeography, climate and soil. The digital map is now available through a web portal (http://bis.iirs.gov.in). 相似文献
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Collins O. Oduor Nancy Karanja Richard Onwong’a Stephen Mureithi David Pelster Gert Nyberg 《Carbon balance and management》2018,13(1):24
Background
Pasture enclosures play an important role in rehabilitating the degraded soils and vegetation, and may also influence the emission of key greenhouse gasses (GHGs) from the soil. However, no study in East Africa and in Kenya has conducted direct measurements of GHG fluxes following the restoration of degraded communal grazing lands through the establishment of pasture enclosures. A field experiment was conducted in northwestern Kenya to measure the emission of CO2, CH4 and N2O from soil under two pasture restoration systems; grazing dominated enclosure (GDE) and contractual grazing enclosure (CGE), and in the adjacent open grazing rangeland (OGR) as control. Herbaceous vegetation cover, biomass production, and surface (0–10 cm) soil organic carbon (SOC) were also assessed to determine their relationship with the GHG flux rate.Results
Vegetation cover was higher enclosure systems and ranged from 20.7% in OGR to 40.2% in GDE while aboveground biomass increased from 72.0 kg DM ha?1 in OGR to 483.1 and 560.4 kg DM ha?1 in CGE and GDE respectively. The SOC concentration in GDE and CGE increased by an average of 27% relative to OGR and ranged between 4.4 g kg?1 and 6.6 g kg?1. The mean emission rates across the grazing systems were 18.6 μg N m?2 h?1, 50.1 μg C m?2 h?1 and 199.7 mg C m?2 h?1 for N2O, CH4, and CO2, respectively. Soil CO2 emission was considerably higher in GDE and CGE systems than in OGR (P?<?0.001). However, non-significantly higher CH4 and N2O emissions were observed in GDE and CGE compared to OGR (P?=?0.33 and 0.53 for CH4 and N2O, respectively). Soil moisture exhibited a significant positive relationship with CO2, CH4, and N2O, implying that it is the key factor influencing the flux rate of GHGs in the area.Conclusions
The results demonstrated that the establishment of enclosures in tropical rangelands is a valuable intervention for improving pasture production and restoration of surface soil properties. However, a long-term study is required to evaluate the patterns in annual CO2, N2O, CH4 fluxes from soils and determine the ecosystem carbon balance across the pastoral landscape.14.
Pilar Burgos Engracia MadejónAlfredo Pérez-de-Mora Francisco Cabrera 《International Journal of Applied Earth Observation and Geoinformation》2008
The spatial distribution of some soil chemical properties and trace element contents of a plot affected by the Aznalcóllar mine spill were investigated using statistical and geostatistical methods to assess the extent of soil contamination. Total and EDTA-extractable soil trace element concentrations and total S content showed great variability and high coefficients of variation in the three examined depths. Soil in the plot was found to be significantly contaminated by As, Cd, Cu, Pb and Zn within a wide range of pH. Total trace element concentrations at all depths (0–60 cm) were much higher than background values of non-affected soil, indicating that despite the clean-up operations, the concentration of trace elements in the experimental plot was still high. The spatial distribution of the different variables was estimated by kriging to design contour maps. These maps allowed the identification of specific zones with high metal concentrations and low pH values corresponding to spots of residual sludge. Moreover, kriged maps showed distinct spatial distribution and hence different behaviour for the elements considered. This information may be applied to optimise remediation strategies in highly and moderately contaminated areas. 相似文献
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Mushtak Jabbar 《地球空间信息科学学报》2013,16(1):34-37
This paper describes the use of the Arc/Info and ArcView GIS tools to estimate soil erosion with Universal Soil Loss Equation (USLE). Calculations are be done by using capabilities available. This study start with a digital elevation model (DEM) of Shaanxi, which was created by digitizing contour and spot heights from the topographic map on 1∶250 000 scale and grid themes for the USLEK andC factors. It is note worthy that USLEK can be obtained by adding the K factor as an attribute to a soil theme's table. TheC can be obtained from tables or using the information about land use and management given by USLE program. A land use theme can be used to add theC factors as an attribute field. The purpose of this study is to establish spatial information of soil erosion using USLE and GIS and discuss the analysis of the soil erosion and slope failures in GIS and formulate the possible framework. 相似文献
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Application of GIS to estimate soil erosion using RUSLE 总被引：9，自引：0，他引：9
Mushtak Talib Jabbar 《地球空间信息科学学报》2003,6(1):34-37
This paper describes the use of the Arc/Info and ArcView GIS tools to estimate soil erosion with Universal Soil Loss Equation (USLE).Calculations are be done by using capabilities available.This study start with a digital elevation model(DEM) of Shaanxi,which was created by digitizing contour and spot heights from the topographic map on 1:250000 scale and grid themes for the USLE K and C factors.It is note worthy that USLE K can be obtained by adding the K factor as an attribute to a soil theme‘s table.The C can be obtained from tables or using the information about land use and management given by USLE program.A land use theme can be used to add the C factors as an attribute field.The purpose of this study is to establish spatial information of soil erosion using USLE and GIS and discuss the analysis of the soil erosion and slope failures in GIS and formulate the possible framework. 相似文献
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Mikael Egberth Gert Nyberg Erik Næsset Terje Gobakken Ernest Mauya Rogers Malimbwi Josiah Katani Nurudin Chamuya George Bulenga Håkan Olsson 《Carbon balance and management》2017,12(1):8
Background
Soil carbon and biomass depletion can be used to identify and quantify degraded soils, and by using remote sensing, there is potential to map soil conditions over large areas. Landsat 8 Operational Land Imager satellite data and airborne laser scanning data were evaluated separately and in combination for modeling soil organic carbon, above ground tree biomass and below ground tree biomass. The test site is situated in the Liwale district in southeastern Tanzania and is dominated by Miombo woodlands. Tree data from 15 m radius field-surveyed plots and samples of soil carbon down to a depth of 30 cm were used as reference data for tree biomass and soil carbon estimations.Results
Cross-validated plot level error (RMSE) for predicting soil organic carbon was 28% using only Landsat 8, 26% using laser only, and 23% for the combination of the two. The plot level error for above ground tree biomass was 66% when using only Landsat 8, 50% for laser and 49% for the combination of Landsat 8 and laser data. Results for below ground tree biomass were similar to above ground biomass. Additionally it was found that an early dry season satellite image was preferable for modelling biomass while images from later in the dry season were better for modelling soil carbon.Conclusion
The results show that laser data is superior to Landsat 8 when predicting both soil carbon and biomass above and below ground in landscapes dominated by Miombo woodlands. Furthermore, the combination of laser data and Landsat data were marginally better than using laser data only.18.
Satellite remote sensing images play an important role in environmental monitoring for mining industry. There are a number of environmental variables, soil and surface variables, associated with mineral activities, that are to some extent detectable easily with satellite earth observation data. The aim of this paper is to detect the quarrying-mining activities are located in seismically active regions of Turkey using satellite images. Because mining-quarrying blasts have been observed and listed as earthquakes in the seismicity catalogue by seismic networks. The presence of mines-quarries in an active seismic zone can cause errors during the analysis of the distribution of microseismicity and the editing of seismic catalogs. Therefore, this study is a meaningful analysis for seismic networks interested in tectonic researches, because it highlights areas where need to pay careful attention is advisable for identification of mining-quarrying blasts. The new digital database was created using the satellite images of mining and quarrying areas taken from the Google Earth program (http://maps.google.com). In the study, approximately 721 known and illegal mining-quarrying sources have been detected. That were organized in an informational atlas includes information on locations, geographic coordinates and satellite images of the mining-quarrying sources in Turkey which can be distributed as a CD or on the WEB. Kekovali et al. (International Journal of the Physical Sciences 6(15), 3784–3794, 2011) estimated potential mining and quarry areas of Turkey from the Kandilli Observatory Earthquake Research Institute & National Earthquake Monitoring Center (KOERI-NEMC) seismic catalogs using daytime to nighttime ratio analysis (Qm). In this study, the correlation between the estimated satellite locations of the mining and quarrying activities and the areas with Qm?≥?2.0 values taken from the previous study was examinated. The result of the study, the important potential mining-quarrying sources were estimated for Turkey includes: Kütahya, Mu?la, Manisa, Bal?kesir, ?stanbul, ?zmit, Edirne, Bursa, Bilecik, Tekirda?, Ankara, Konya, Eski?ehir, Malatya, Yozgat, K?r?kkale, Malatya, ?anl?urfa, Sinop, Trabzon. Monitoring and controlling mining-quarrying activities through traditional methods is quite difficult due to high costs and lengthy time in obtaining accurate and updated maps. The use of satellite images is an inexpensive and effective tool for mapping large mining-quarrying activity areas that can be also used to supplement data from environmental studies. In the future work, the satellite database can be processed and analyzed in order to produce a proper GIS database that includes important mining-quarrying sources of Turkey. 相似文献
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Anthony C. Robinson Scott Pezanowski Sarah Troedson Raechel Bianchetti Justine Blanford Joshua Stevens 《制图学和地理信息科学》2013,40(5):415-426
Maps are a primary means for supporting information sharing and collaboration in emergency management and crisis situations. While a variety of formalized map symbol standards for emergency contexts exist, they have not been widely adopted by mapmakers. Informal symbol conventions are commonly used within emergency management stakeholder groups, but until now there has not been a flexible mechanism for discovering, sharing, and previewing these symbol sets among mapmakers. In this paper, we describe the design and development of the Symbol Store, a visually enabled, web-based interactive tool intended to help mapmakers share point symbols. The Symbol Store allows users to browse symbols by keyword, category tags, and contributors. It also allows for symbols to be previewed on realistic maps prior to download. An initial prototype of the Symbol Store was evaluated by flood mapping experts from the State of California, and the results of this user study led to multiple refinements now implemented in the public version of Symbol Store located at www.symbolstore.org. 相似文献
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Usefulness of Landsat imagery in discerning major arid zone soils has been studied. Results are based on analysis of Band 7 coverage and Band 5 and 7 for a limited area followed by a comparison of these with the known soil distribution as seen in Bikaner, Jodhpur and part of Jalore, Pali and Nagaur districts. Results show that at Band 7 the dominant course loamy Typic Camborthids in association with dunes could be recognised. Vegetation was found non-interfering though surface soil moisture variation of the period immediately following monsoon months (Sept.–Dec.) appeared to do so. Hardpan soils were identifiable largely by their associated features than by soil characteristics proper. Fine loamy typic Camborthids could not be recognised at series level and as a group also these could be identified only in post-monsoon period when the land is devoid of much of its vegetation cover. Saline areas could be recognised but those occurring in South-eastern tract were largely inseparable from adjoining shallow soils. For these, Band 5 image of monsoon months was quite satisfactory. For all other soils, Band 7 was better than Band 5. Though light brown sandy soils in association with dunes are the dominant formations, past evolutionary history and source rock variability have given considerable heterogeniety to the soil cover of the arid zone. Natural resource survey activity over the years has provided ground information for nearly 30 percent of Westren Rajasthan and this incidentally covers major soils of the area albeit with few exceptions. With the Landsat imagery now becoming accessible, it was thought befitting to see how far soil variations as recognised in the course of above surveys could be discerned from the Landsat. Some encouraging reports on the use of the Landsat or similar data in small cale soil mapping are available in literature (Kristof and Zachary, 1970; El-Baz, 1978; Everitt and Gerbermann 1977). In our own country also usefulness of this tool has been demonstrated by Krishnamurthy and Srinivanan (1973) and Hilwig (1975). Recently Bhandariet al; (1976) while working in northern part of arid zone have shown that soil salinity mapping could be attempted with the help of Landsat data. 相似文献