Spatial Data Mapping Research Articles

Impacts of Contaminants on Groundwater Quality in Rukpokwu, Delta Region of Nigeria

This study investigated the characterization of borehole sediment and the impact of contaminants on groundwater quality in the Rukpokwu Community in the delta of Nigeria. The investigation supported by spatial data supported by GIS techniques provides a data baseline for the monitoring of organo-contaminants in groundwater quality in Rukpokwu. This low pH of the groundwater and irritation of the throat and mouth became a concern to the residents. This study is necessary because of the limited data on the level of organic contamination in groundwater in this section of the delta of Niger in Nigeria. So, there was a need to track the source of contamination in this part of the delta of Niger in Nigeria. These previous studies have suggested a highly permeable open aquifer in similar deltaic terrain. Ten (10) samples of borehole sediment and water collected at 30 m depth were being analyzed for textural and physicochemical characteristics. The parameters analyzed include Iron (Fe), Total Petroleum Hydrocarbon &Total Hydrocarbon Content (i.e., TPH and THC respectively) of borehole sediment in association with groundwater quality. Ten (10) sediment samples collected at a depth of 30m and were being analyzed for mean, sorting, skewness and kurtosis, using standard laboratory procedures. Coarse silt, poorly sorted and negatively skewed were the characteristics of the borehole silt. The Kurtosis suggested the leptokurtic and platykurtic nature of the sediment. The TPH and THC range from 0.58 to 0.85 mg/L and 1.26 to 2.84 mg/L respectively. The Fe and pH range in the sediment were 0.85 to 2.46 mg/L and 4.43 to 6.02 respectively. However, Fe in the groundwater ranges from 0.12 to 0.21 mg/L. The results were above the World Health Organization's acceptable contaminant level. Based on the piece of evidence provided by spatial data mapping and textural parameters, the characteristics of the borehole sediment significantly controlled the ingress of contaminants into the groundwater. The source of groundwater contamination is the abnormal concentrations of organic contaminants. These results significantly impact human health in the food chain. This study provides information to the environmental agency for a clean-up process.

Spatial distribution prediction of agro-ecological parameter using kriging

In modern agroecology, one of the most pressing problems is the problem of spatial data mapping. The development of information technology opens up a wide range of approaches for solving this problem. One of these approaches is based on the use of geostatistical methods. This study was carried out with the aim of developing ideas about the applicability of the ordinary kriging method for predicting the spatial distribution of the agro-ecological indicator with identifying the boundaries of in-field heterogeneity according to remote sensing data. For the model computational experiment, aerial photographs of the agricultural field in the red and near infrared ranges were used, which made it possible to obtain sets of uniformly distributed values of the vegetative index NDVI that were randomly generated. The high spatial resolution of the images allowed us to analyze the observational data for the studied agricultural field.

Relationships between landslides and land use changes in the Sanbagawa and Mikabu Belts, Shikoku, Japan

Abstract. Changing land use is an increasingly important issue as human habits, behaviors, and needs change. There has been an increase in land and agricultural abandonment in some places of the world. In Japan, movement of the population from rural to urban areas have resulted in much land and agricultural abandonment. In 2016, a land ministry survey showed that 4.1 million hectares of land in Japan had unclear ownership, with farmland making up 16.9% of the total. As vegetation cover changes after land abandonment, this temporal and spatial effect may have important effects on geomorphic processes such as landslide susceptibility and landslide kinematics.Here we track long-term land use changes over vegetated landslide areas of the Sanbagawa and Mikabu Belts of Shikoku Island, Japan. The Sanbagawa and Mikabu Belts are metamorphic belts that run across Southwest Japan, and are home to numerous large crystalline schist landslides, including the widely-studied slow but continuously moving Zentoku landslide. Villages and communities have been built on these landslide areas due to historical and cultural factors, as well as the fertility of the soil. Consequently, given the changing land uses including land abandonment in these landslide areas over time, we use long-term high-resolution land cover vegetation datasets to examine first the long-term land use changes, and then use statistical methods to explore their relationships with landslide susceptibility and kinematics. Mapping of spatial data and their analysis using GIS constitute a core part of the research. The results suggest interconnections between land use changes and land movement.

Interactive mapping of urban tree benefits using Google Fusion Tables and API technologies

Geographic Information Systems (GIS) and web-based GIS platforms are typically used by large organizations and government agencies for the purpose of data storage, query, analysis, and spatial data mapping. Google Fusion Tables, however, provides cloud-based computing services for data management and easy user collaboration through the Google Maps interface. Fusion Tables are oriented towards smaller organizations that previously were unable to publish data online due to limitations of database knowledge, high cost of start-up, and restrictions on implementation. In this research project, we assess the functionality and limitations of Fusion Tables and associated API as a spatial data management system by programming an interactive web-based mapping platform, the CityTrees.ca Project, designed to showcase the benefits of trees growing on the campus of Ryerson University, Toronto. Specifically, Fusion Tables functionality, such as data storage and manipulation, is used to build a query interface (both attribute and spatial) that permits users of CityTrees.ca to search for and map trees by species, diameter, height, and location. We found that Fusion Tables performed well as a storage medium for our campus tree data, which could easily be explored through our creation of a JavaScript-enabled query tool. Our project provides a unique roadmap for small to medium-sized urban forestry organizations and environmental non-profits seeking to create interactive mapping applications where data privacy and advanced spatial analysis are not fundamental.

Institutionalization of Racial Inequality in Local Political Geographies

Municipalities create a local political geography that can institutionalize subordinate positions for minority groups. Most importantly, local governments determine which areas are incorporated into a municipality through annexation and which are excluded. Through these powers, local governments can diminish or deny minority political standing in local affairs, limit access to public services, and reduce the value of minority property. The boundaries are a component of racial residential segregation. Racially disparate application of local governments' power to shape local political geography creates barriers to equality that are difficult to discern on the ground, but which can be made visible by the mapping of spatial data. This study presents four cases where governmental decisions concerning a municipal boundary have institutionalized racial inequality, which is documented with maps created from public GIS data and other public records (e.g., City Council meeting minutes) as well as legal documents. This pattern of systematic exclusion of minority neighborhoods is receiving attention in the legal community, but studies in the social sciences have been limited.

Role of GIS in Distribution Power Systems

Abstract —With the prevalence of computer and developmentof information technology, Geographic Information Systems(GIS) have long used for a variety of applications in electrical en-gineering. GIS are designed to support the analysis, management,manipulation and mapping of spatial data. This paper presentsseveral usages of GIS in power utilities such as automated routeselection for the construction of new power lines which usesa dynamic programming model for route optimization, loadforecasting and optimizing planning of substation’s location andcapacity with comprehensive algorithm which involves an accu-rate small-area electric load forecasting procedure and simulatesthe different cost functions of substations. Index Terms —Geographic information systems (GIS), optimallocation and capacity, power distribution planning, route selec-tion, spatial load forecasting. I. I NTRODUCTION T HE ability to consume and control energy is one ofthe initial contributions to the development in our lifeall over the years. The use of GIS in power system hasgreatly enhanced the efficiency in energy sector. Proximityto the furthest customer and high cost to invest capital, arethe reasons that make the distribution system as an importantpart of electrical utility, which endeavor to improve the re-liability of general power system [1]. Problems of planningin distribution system can be solved by using new methodsand specific techniques. Complexity of electrical distributionsystem and necessity of accurate up-to-date information of thenetwork assets is a reasonable intention for introducing newmethod of information technology. GIS software breakthroughtechnology which help utilities discover new things abouttheir investments and risks, reduce the cost of manual main-tenance of the maps, and allows the simultaneous assessmentof technical, financial, and environmental factors. GIS havebeen proven to be a workable system to connect databaseinformation such as billing, material account, distributionanalysis and outage reporting in power utility. GeographicInformation Systems (GISs) are now being used widely forthe mapping and modeling of utility network systems. Utilitiesuse network models to monitor and analyze their distributionsystems. Network analysis conclude network tracing whichselects a particular path through the network based on user’scriteria, network routing which determines the optimal paththat has the shortest and the fastest distance and minimum

Application of Fuzzy Sets Function for Land Attributes Mapping

A study was conducted to evaluate the potential use of Geographical Information System (GIS) for mapping thebiophysical resources of watershed PC-based GIS soft-wares were used in the analysis, processing and mapping of spatialdata. The conventional mapping technique that presents land attribute in form of polygon with abrupt change across classboundaries was improved using Fuzzy technique. This technique involves the generation of membership maps for each soiltype based on the relationship between the soil type and it's forming factors like geology, elevation, slope gradient, slopeaspect, slope curvature, and land cover. The fuzzy technique was found to be more appropriate than the conventionaltechnique of mapping in expressing continuous and gradually changing soil or land attributes. Validation with observed soilor land attributes values indicated that root mean square error (RMSE) obtained for Fuzzy method was lower than that fromthe conventional method

System Integration of GIS and a Rule-Based Expert System for Urban Mapping

A rule-based expert system has been the most common artificial intelligence (AI) technique for system integration with geographic information systems (GIS) because of its simple rule structure. In this paper, a rule-based expert system is presented that uses an interactive question-and-answer sequence integrated with GIS for spatial data mapping. The integrated system consists of three main parts: expert, user, and map. Rules can be constructed easily in the expert part using English. Users can derive a solution to a specific problem from the rules in the user part through the interactive question-and-answer sequence. The solution can then be mapped directly in the GIS (map) part. This system is applied to the interactive interpretation and mapping of aerial photographs for an urban area. The land-use/land-cover map results in 93.44 percent overall accuracy with a kappa index of 0.9288.

Wavelet analysis residual kriging vs. neural network residual kriging

This paper deals with the problem of spatial data mapping. A new method based on wavelet interpolation and geostatistical prediction (kriging) is proposed. The method – wavelet analysis residual kriging (WARK) – is developed in order to assess the problems rising for highly variable data in presence of spatial trends. In these cases stationary prediction models have very limited application. Wavelet analysis is used to model large-scale structures and kriging of the remaining residuals focuses on small-scale peculiarities. WARK is able to model spatial pattern which features multiscale structure. In the present work WARK is applied to the rainfall data and the results of validation are compared with the ones obtained from neural network residual kriging (NNRK). NNRK is also a residual-based method, which uses artificial neural network to model large-scale non-linear trends. The comparison of the results demonstrates the high quality performance of WARK in predicting hot spots, reproducing global statistical characteristics of the distribution and spatial correlation structure.

Fortran iv program for grey-level mapping of spatial data

Afortran iv computer program for grey-level mapping of spatial data using a CDC 6600 is described. The program produces maps for irregularly distributed data in as many as 10 intensity levels which are displayed in grey tones by a lineprinter. Unlimited map size and unrestricted data input provide for as many as 5000 data points per 13-in.-wide strip of map. The program is easily modified for other installations. Examples are given of geochemical analyses of stream sediments in Northern Ireland.

Fortran IV program for grey-level mapping of spatial data

Fortran IV program for grey-level mapping of spatial data