Soil erosion is a serious problem arising from agricultural intensification, land degradation and other anthropogenic activities. Assessment of soil erosion is useful in planning and conservation ...works in a watershed or basin. Modelling can provide a quantitative and consistent approach to estimate soil erosion and sediment yield under a wide range of conditions. In the present study, the soil loss model, Revised Universal Soil Loss Equation （RUSLE） integrated with GIS has been used to estimate soil loss in the Nethravathi Basin located in the southwestern part of India. The Nethravathi Basin is a tropical coastal humid area having a drainage area of 3128 km2 up to the gauging station. The parameters of RUSLE model were estimated using remote sensing data and the erosion probability zones were determined using GIS. The estimated rainfall erosivity, soil erodibility, topographic and crop management factors range from 2948.16 to 4711.4 MJ/mm.ha-1hr-1/year, 0.10 to 0.44 t ha-1 -MJ-1.mm 1, 0 to 92,774 and 0 to 0.63 respectively. The results indicate that the estimated total annual potential soil loss of about 473,339 t/yr is comparable with the measured sediment of 441,870 t/yr during the water year 2002 2003. The predicted soil erosion rate due to increase in agricultural area is about 14,673.5 t/yr. The probability zone map has been derived by the weighted overlay index method indicate that the major portion of the study area comes under low probability zone and only a small portion comes under high and very high probability zone. The results can certainly aid in implementation of soil management and conservation practices to reduce the soil erosion in the Nethravathi Basin.
•Geographic information system has been used to Prepare a groundwater vulnerability map of the study area using DRASTIC Model.•The impact of pipeline interdiction to the underlying aquifers of the ...study area has been highlighted.•The ROC/AUC curves and PAHs has been used to validate DRASTIC Model.
Extensive environmental pollution has affected the water resource, agricultural lands, economy and health of the inhabitants of Ahoada communities of the Niger Delta region, Nigeria. The main sources of pollution are oil spills emanating from pipeline interdiction and production-related spillages. Oil spills in the Niger Delta adversely affects the physical, chemical and biological properties of soil, which subsequently results in food shortages due to the reduction of nutrient contents of soils. Therefore, it is crucial to understand the patterns and the types of contaminants for appropriate remediation of the polluted areas. This study applied a novel DRASTIC model approach, incorporating a data-driven method Weight of Evidence (WoE) to examine subsurface aquifer vulnerability to oil spills contamination and present same as in the maps. Geographic Information System (GIS) in combination with DRASTIC and a modified DRASTIC model called DRAPSTIC were used in assessing the extent and vulnerability of the aquifers of the area to contamination. The maps of the DRAPSTIC show similarity in terms of the distribution and classification of the vulnerability index. Very high and high vulnerability classes covered larger areas in Ahoada east under DRAPSTIC compared to DRASTIC. However, under the same DRAPSTIC, larger areas were covered by low vulnerability class in Ahoada West.
To gain a better understanding of the global application of soil erosion prediction models, we comprehensively reviewed relevant peer-reviewed research literature on soil-erosion modelling published ...between 1994 and 2017. We aimed to identify (i) the processes and models most frequently addressed in the literature, (ii) the regions within which models are primarily applied, (iii) the regions which remain unaddressed and why, and (iv) how frequently studies are conducted to validate/evaluate model outcomes relative to measured data. To perform this task, we combined the collective knowledge of 67 soil-erosion scientists from 25 countries. The resulting database, named ‘Global Applications of Soil Erosion Modelling Tracker (GASEMT)’, includes 3030 individual modelling records from 126 countries, encompassing all continents (except Antarctica). Out of the 8471 articles identified as potentially relevant, we reviewed 1697 appropriate articles and systematically evaluated and transferred 42 relevant attributes into the database. This GASEMT database provides comprehensive insights into the state-of-the-art of soil- erosion models and model applications worldwide. This database intends to support the upcoming country-based United Nations global soil-erosion assessment in addition to helping to inform soil erosion research priorities by building a foundation for future targeted, in-depth analyses. GASEMT is an open-source database available to the entire user-community to develop research, rectify errors, and make future expansions.
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•Peer-reviewed research literature on soil-erosion modelling was reviewed.•66 soil-erosion scientists from 25 countries contributed to this study.•Overall, 8471 articles identified as potentially relevant were reviewed.•1697 articles were reviewed in a comprehensive manner extracting 42 attributes.•A free and open-source database was created.
The complexity of tenure claims in the informal settlements has been difficult to incorporate into the formal systems owing to their dynamic and continuously changing nature. Innovative tools are ...therefore required to capture these claims. This requires the development of a cadastral data model specifically for informal settlements that would document such claims to make it easier to manage the current situation as well as prepare for future formalization processes such as regularization or relocation. The main aim of this study was develop a typology of informal settlements in Kenya as a basis for developing a cadastral data model. A data model was developed based on the Social Tenure Domain Model (STDM) using open source geo-solution (SOLA). The model was found to be generally suitable for all the different informal settlement typologies.
The use of GIS (Geographic Information System) systems to manage investments in cities is becoming more and more popular. Current technology enables the use of GIS system with the use of network ...technology. In this way, the same maps can be used by users of different units. Implementation of investments in cities often requires cooperation between different institutions, offices and other entities. For this purpose, it is possible to create electronic communities, which can be realized through electronic channels. This concept was called the Regional Business Spatial Community. The GIS tools can be considered as an integrating element between actors in the environment. GIS tools can be an element integrating the environments in which investments are made. On shared maps, not only existing facilities can be marked, but also implemented, planned or even postulated projects. The aim of the paper is to present the results of research conducted to identify whether, at a specific stage, the use of GIS technology in cities can serve as a platform conducive to the creation of regional electronic communities to facilitate investment in the city.
The study covered 10 largest cities in Poland in the form of observations. In the case of 5 entities, a questionnaire interview was conducted. Based on the analysis of the results, it can be concluded that from a technical point of view, GIS software can be such a platform. The problem is the business, information and organizational platforms.
Urban green and blue spaces provide mental and physical health benefits for their surrounding communities, but the key to many of these benefits is the utilization of the urban greenspace for ...recreation or relaxation. For some communities, use is limited by physical access to the greenspace while for other communities, the characteristics of the greenspace play an important role in encouraging or discouraging use. What drives communities to use their local greenspace with respect to all other available greenspace in an urban area remains an underexplored question. To fill this gap, we leverage a large human mobility dataset to track a year of park visitation by residents across the Phoenix, AZ, metropolitan area combined with a spatial autoregressive model using spatially lagged dependent variables. Our results suggest that it is not vegetation but the presence of water features within a park that encourages higher visitation to local parks. Water features also influence visitation to parks outside a communities local area; its presence within a local park decreased how often individuals visited non-local parks as a proportion of their total park visitation. We discuss the implications of these finding in the context of a desert city that lacks both greenspace and water.
Air pollution epidemiological studies increasingly rely on high-resolution exposure prediction models. However, to date, few models of this type exist for use in China.
We produced a national ...land-use regression model (LUR) to estimate monthly average PM2.5, PM10 and NO2 from 2014 to 2016 in China.
We developed a spatiotemporal semi-parametric model using generalized additive mixed models. A variety of predictor variables were included in model: time varying meteorological data, high resolution land cover data from Globaland30, satellite measures of aerosol optical depth, and Geographic Information System (GIS)-derived predictors. We assessed model performance with two cross-validation (CV) approaches, including hold-out CV, and 10-fold CV.
Over 22,000 monthly observations at 1382 monitoring locations were included to estimate the air pollution exposure. The time-varying spatial terms explained 87%, 71%, and 69% of variability with a hold-out cross-validated R2 of 0.85, 0.62, and 0.62 for PM2.5, PM10 and NO2 models, respectively. Models show that meteorological variables, population density, elevation, distance to road, and land cover types were important predictors for air pollution exposure.
we have developed a new nationwide model to estimate residence-level air pollution exposures, which can be used in studies of the chronic adverse effects of air pollution.
•We developed national scale spatiotemporal land use models to estimate monthly PM2.5, PM10 and NO2 concentrations in China.•For the PM2.5, PM10 and NO2 models, predictors explained 87%, 71%, and 69% of variability of the pollutant distributions.•Meteorological, AOD, and GIS-derived covariates were important predictors for air pollution exposure.
The article deals with the application of GIS in different types of cities. The development of GIS technology is opening up new applications. In addition to the collection and cartographic ...visualisation of data, higher-level information functions such as automatic analysis, control, spatial planning or decision support can be realised. GIS technology can also be used to visualise abstract spaces. The article deals with the application of GIS in different types of cities. The article is intended to be the result of an analysis of the direction of the use of GIS technology in public administration in Poland. For this purpose, a model was developed to examine the state of GIS technology application. Two criteria were used to determine the state: groups of factors influencing the use of GIS technology (organisational, functional, informational and technical) and the level of maturity of GIS tools. Four levels were distinguished (from zero, i.e. no application of GIS technology, to a third level indicating the strategic importance of the tools studied). To this end, an empirical study was developed to determine the level of maturity of the application of the tools in question. After analysing the results, it can be concluded that the systems studied are still evolving. From the perspective of the proposed model, it can be assumed that the development of GIS tools has reached the second level in most of the surveyed offices. However, it will still be difficult to develop the software if not all the currently available GIS software capabilities are used.
Geographic information systems (GIS) are fundamental information technologies. The capabilities and applications of GIS continue to rapidly expand, requiring practitioners to have new skills and ...competencies, especially in computer science. There is little research, however, about how best to prepare the next generation of GIScientists with adequate computer science skills. This article explores how U.S. geography departments are introducing and developing computer science and programming skills in their geography and GIS degree programs. We review the degree requirements in fifty-five geography departments and discover that forty-four of them offer some kind of GIS programming course. Of the 210 separate degree options identified, however, only 22 require one of these courses for a degree. There is little consistency or emphasis on computer science and programming skills in geography or GIS degrees, despite the immense importance of these components in geography and GIS careers. We propose future research along distinct investigative tracks to build a research-based understanding of the educational interactions among GIS, computer science, programming, and geography.
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