Geographic Information System Software Package Research Articles

ESTIMATION OF WHEAT CROP PRODUCTIVITY OF DISTRICT NAWAB SHAH USING METRIC EEFLUX IMAGERY

Water scarcity and food security are global concerns, which require morefood production from less water. Therefore, for effective management of water resources and improved food production, identification of Crop water Productivity (CWP) is of prime importance. Current study was conducted at Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, Pakistan during year 2020 estimates CWP of wheat during the Rabi season (winter season) in the Nawab Shah District of Sindh (located in Rorhi canal command area) using Mapping Evapotranspiration at High Resolution with internalized calibration (METRIC) - Earth Engine Flux (EEFLUX) application. Cloud corrections were applied where cloud cover was approximately 50% and missing data were interpolated. Actual evapotran spiration (ETa ) for each season (initial, development, mid and late, required for estimating CWP) were calculated from reference evapotranspiration (ETr ) by evapotranspiration factor (ETr F) which were available at the Food and Agriculture Organization (FAO) website, using geographical information system software package (ARC-GIS). Total ETa for the entire season came out to be 367.57 mm. Inshort, wheat crop productivity can be assessed by using matric EEFLUX imagery

Use of Geographic Information Systems by American Evaluation Association Members in their Professional Practice

Background: As geographic information systems (GIS) technology continues to develop and expand in its capacity and applications, it is becoming increasingly useful to many disciplines. Even so, little has been written about the place of GIS technology in evaluation practice, and there is a paucity of information as to the extent to and applications for which evaluation practitioners use such technology.
 Purpose: In this investigation, the prevalence and common applications of GIS technology in professional evaluation practice are examined. Particularly, the study was designed to estimate what proportion of American Evaluation Association (AEA) members who self-identify as evaluation practitioners use GIS in their practice, if at all, and, if so, to what extent. For those who use GIS in their evaluation practice, the specific GIS software packages and applications used also are explored.
 Setting: Not applicable.
 Intervention: Not applicable.
 Research Design: A simple random sample of American Evaluation Association (AEA) members were surveyed, with an emphasis on evaluation practitioners.
 Findings: Less than less than half (41.04% ±6.09%) of AEA members who consider themselves evaluation practitioners have ever used GIS in their evaluation practice and less than one-third (31.47% ±5.75%) have received some form of training in GIS methods. Data visualization is, by far, the most frequent application of GIS in evaluation practice.
 Keywords: American Evaluation Association; geographic information systems; technology in evaluation; evaluation practice; research on evaluation

A Five-Star Guide for Achieving Replicability and Reproducibility When Working with GIS Software and Algorithms

The availability and use of geographic information technologies and data for describing the patterns and processes operating on or near the Earth’s surface have grown substantially during the past fifty years. The number of geographic information systems software packages and algorithms has also grown quickly during this period, fueled by rapid advances in computing and the explosive growth in the availability of digital data describing specific phenomena. Geographic information scientists therefore increasingly find themselves choosing between multiple software suites and algorithms to execute specific analysis, modeling, and visualization tasks in environmental applications today. This is a major challenge because it is often difficult to assess the efficacy of the candidate software platforms and algorithms when used in specific applications and study areas, which often generate different results. The subtleties and issues that characterize the field of geomorphometry are used here to document the need for (1) theoretically based software and algorithms; (2) new methods for the collection of provenance information about the data and code along with application context knowledge; and (3) new protocols for distributing this information and knowledge along with the data and code. This article discusses the progress and enduring challenges connected with these outcomes.

Quantum GIS (QGIS): An introduction to a free alternative to more costly GIS platforms

Geographic information system (GIS) software packages can be prohibitively expensive, causing many to shy away from mapping and spatial analysis. This 7-page fact sheet written by Jeffry M. Flenniken, Steven Stuglik, and Basil V. Iannone III and published by the UF/IFAS School of Forest Resources and Conservation introduces the reader to a free GIS software package called Quantum GIS (QGIS), walking the reader through simple GIS processes that can be used to visualize spatial patterns of importance to a variety of fields, including natural resources, agriculture, and urban planning. Learn how to create a land-cover map for a county of interest and create heatmaps that illustrate the density of a given attribute (Florida Springs for this example). This publication will benefit those interested in incorporating GIS into their work but who are unable to afford expensive proprietary GIS software packages, as well as anyone interested in learning a new GIS software package. https://edis.ifas.ufl.edu/fr428

Process modeling for slope and aspect with application to elevation data maps

Learning about the behavior of land surface gradients and, in particular, slope and aspect over a region from a dataset of levels obtained at a set of (possibly) irregularly spaced locations assumes importance in a variety of applications. A primary example considers digital terrain models for exploring roughness of land surfaces. In a geographic information system software package, gradient information is typically extracted from a digital elevation/terrain model (DEM/DTM), which usually presents the topography of the surface in terms of a set of pre-specified regular grid points, each with an assigned elevation value. That is, the DEM arises from preprocessing of an originally irregularly spaced set of elevation observations. Slope in one dimension is defined as “rise over run”. However, in two dimensions, at a given location, there is a rise over run in every direction. Then, the slope at the location is customarily taken as the maximum slope over all directions. It can be expressed as an angle whose tangent is the ratio of the rise to the run at the maximum. In practice, at each point of the grid, rise/run is obtained through comparison of the elevation at the point to that of a set of neighboring grid points, usually the eight compass neighbors, to find the maximum. Aspect is defined as the angular direction of maximum slope over the compass neighbors. We present a fully model-based approach for inference regarding slope and aspect. In particular, we define process versions of the slope and aspect over a continuous spatial domain. Modeling slopes takes us to directional derivative processes; modeling angles takes us to spatial processes for angular data. Using a stationary Gaussian process model for the elevation data, we obtain distribution theory for slope and associated aspect as well as covariance structure. Hierarchical models emerge; fitting in a Bayesian framework enables attachment of uncertainty. We illustrate with both a simulation example and a real data example using elevations from a collection of monitoring station locations in South Africa.

Overview of the application of geospatial technology to groundwater potential mapping in Nigeria

Sustainable development of groundwater resources in many developing nations like Nigeria is hampered by paucity of information about the resource. Geospatial technology has provided useful information in understanding the distribution of groundwater throughout the world for the purpose of planning, exploration, monitoring and conservation. Numerous studies have integrated remote sensing (RS) and geographical information system (GIS) in the assessment of groundwater potential in different parts of Nigeria. This paper therefore aims to review the literatures and reveal the successes and most importantly the challenges faced by such studies and provide useful recommendations for improvement in future research. A global perspective of advances in the application of geospatial technology to groundwater mapping was first captured from where the strength and weaknesses of the same application in Nigeria in terms of methodology of data extraction, modelling and validation were assessed. The review shows that less than 20 bibliographies are available with about 50% from the south-western part of the country. Few parameters controlling groundwater are often analysed and categorised without any standard. Most models are produced from software packages that do not allow weighting of thematic layers hence cannot incorporate expert judgements. Areas needing urgent attention for improvement include: time of remote sensing data acquisition, methods of parameter extractions, standard GIS software packages used, novel models and comparison between models and the need for model and map validations. Recommendations on country wide coverage of groundwater potential assessment, provision of groundwater monitoring facilities and strict adherence to groundwater development standards were also made.

The implications of land use/cover dynamics on resources development in Tubah sub-division, Cameroon

The environment at various scales is greatly modified through the activities of man and his dynamic science and technology. These modifications essentially constitute land use/cover changes. This paper describes the implications of land use dynamics on resource development in Tubah Sub-division over time and space from 1983 to 2013. This research has made use of remote sensing techniques and Geographic Information System (GIS) in describing land use/cover changes in Tubah Sub-division. Primary data was obtained through field observations and ground truthing in order to confirm observations on satellite imageries. Land use maps were produced using the GIS software packages of Google Earth, ENVI 4.3, Global Mapper 15 and ArcGis 10.2. Maps were generated to show changes in land use/cover which were transposed into tables and bar graphs to show the magnitude of changes, percentage of change and the rate of change. These changes are necessary for economic development and social progress, but often come at a substantial cost on the environment and resources. The analysis of static land use maps of 1983, 2000, and 2013, all pointed to the fact that, there have been significant changes observed on forest cover, farmland, grazing land and settlement land uses.Keywords: Land use/cover, Dynamics, Remote Sensing Techniques, Geographic Information System, Resource Implications, Tubah

LEFT—A web‐based tool for the remote measurement and estimation of ecological value across global landscapes

Abstract The overall aim in the development of the Local Ecological Footprinting Tool (LEFT) was to design a web‐based tool that could provide quickly obtained quantitative data on ecological risk to assist landowners when making land‐use change decisions. The Local Ecological Footprinting Tool works for almost any region in the world and uses freely available satellite imagery, biotic and abiotic data from existing global databases, models and algorithms to deliver a customised report for a selected area within one hour of job submission. Biotic data automatically obtained for a selected landscape includes terrestrial vertebrate and plant species occurrence data, information on their conservation status and remotely sensed vegetation productivity. Abiotic information obtained includes temperature, precipitation, water availability, insolation, topography, elevation, distribution of urban infrastructure and location of wetlands. The tool performs a number of analyses on the biotic and abiotic data to produce maps for the selected area at a 30 m resolution depicting land cover type, numbers of globally threatened terrestrial vertebrate and plant species, beta‐diversity of terrestrial vertebrates and plants, habitat intactness, wetland habitat connectivity, numbers of migratory species and vegetation resilience. Results are also aggregated to produce a summary map demonstrating areas of high and low ecological risk across the selected area. The Local Ecological Footprinting Tool has been designed to be intuitive to use, requiring no specialised software or user expertise. Input is extremely easy and requires the user to highlight the area of interest on a map or using grid co‐ordinates. Output is delivered via the web application and comprises a customised PDF containing the maps and a zip file of geographical information system (GIS) data for the area requested. Users may run an unlimited number of LEFT analyses and download reports free of charge. In addition to the free tool described in this paper, there is also a paid service: individual LEFT analyses can be upgraded for a charge to allow access to the geographically subsetted datasets generated for each report. These data are supplied as a zip file containing raster datasets for the layers in the LEFT analysis in GeoTIFF format. These can be opened and queried in a GIS software package.

Gully erosion: A comparison of contributing factors in two catchments in South Africa

Gully erosion is an environmental, agricultural and social problem requiring extensive research and mitigation actions to control. This study assesses the influence of factors contributing to gully erosion using Geographic Information System (GIS) and Information Value (InfVal) statistics from two catchments coded X12 and W55 in the Mpumalanga province of South Africa. Existing spatial data representing contributing factors; soil, geology, vegetation and land use were analyzed. Topographic variables were extracted from a 10m Digital Elevation Model (DEM) interpolated from map contours, and gullies were mapped from aerial photos with 0.5m spatial resolution. A zonal approach was used to extract the proportion of gullies in each of the contributing factor classes using GIS software packages, and InfVal weighting was performed to determine the influence of each class. Comparison of the results shows the variation in the level of influence of factors contributing to gully erosion. The findings in catchment X12 support a commonly held assumption that gully formation is influenced by duplex soils underlain by colluvium and alluvial deposits on a lower slope position where overland flow converges and accumulates, resulting in high soil moisture. Gullies were also influenced by soils developed over weathered granite, gneiss and ultramafic rocks. The influence of a granite rock was further highlighted in catchment W55 where there is a variable thickness of very deep Hutton dominant soil form and shallow Lithosols with sandy texture, on an area of moderate to steep slopes where overland flow converges and accumulates, with high stream power in overgrazed grassland. An understanding of these factors will assist future modelling of the vulnerability to gully erosion over a wider geographical area.

Land Suitability Evaluation to Determine the Appropriate Areas of Development: A Case Study of Hormuz Island

One of the basic prerequisites for the development of spatial programs and policies is evaluating the land suitability for future land uses based on the principals of ecological sustainability. This analysis is critical in islands due to special characteristics such as limited natural resources, interdependent and more complex ecosystems, high vulnerability to natural hazards, climate change and economic vulnerability. Accordingly, this paper based on the ecological approach and using Geographic Information System software package and Analytic Hierarchy Process and developing appropriate criteria has analyzed the land suitability of Hormuz Island. The findings clearly show the land suitability to develop industrial, agriculture, tourism land uses and can be the basis for planning the future development of the island based on the ecological sustainability.

Integrated GIS and AHP for Marine Aquaculture Site Selection in Penghu Cove in Taiwan

Marine cage culture has been developed quickly in recent years from land-based operation transfer to marine cage culture by government policy in Taiwan. Therefore, the suitable site selection is an important premised and key factor for successful marine cage culture and sustainable development in the future. Especially, it’s greatly influences economic viability by determining capital outlay and affecting running costs, production and mortality. Hence, the decision factors such as climate factors, geographic environmental factors, bio-environmental factors and social-economic factors are more important for site selection. This study use AHP (analytic hierarchy process) to evaluate the criteria weight for site selection. From AHP analysis, the weights of suitability of the four Geographic Information System (GIS) grid themes were 0.322, 0.410, 0.127 and 0.141, respectively. The result shows that the geographic environmental factors are the most important factors in selection suitable marine culture sits in Penghu cove in Taiwan. At the meanwhile, by using ArcMap, a GIS software package, a suitable map was made based on the selected grid themes. The suitable sites for marine cage culture development identified on the individual GIS grid themes, the GIS software and AHP method can be integrated to select objectively the optimal sites for marine cage culture development.

The Implications of Land Use/Cover Dynamics on Resources Development in Tubah Sub-Division, Cameroon

The environment at various scales is greatly modified through the activities of man and his dynamic science and technology. These modifications essentially constitute land use/cover changes. This paper describes the implications of land use dynamics on resource development in Tubah Sub-division over time and space from 1983 to 2013. This research has made use of remote sensing techniques and Geographic Information System (GIS) in describing land use/cover changes in Tubah Sub-division. Primary data was obtained through field observations and ground truthing in order to confirm observations on satellite imageries. Land use maps were produced using some GIS software packages such as Google Earth, ENVI 4.3, Global Mapper 15 and ArcGis 10.2. Maps were generated to show changes in Land use/cover which were transpose into tables and bar graphs to show the magnitude of changes, percentage of change and the rate of change. The analysis of static land use maps of 1983, 2000, and 2013, all pointed to the fact that, there have been significant changes observed on forest cover, farmland, grazing land and settlement land uses

A brief review of spatial analysis concepts and tools used for mapping, containment and risk modelling of infectious diseases and other illnesses

Fast response and decision making about containment, management, eradication and prevention of diseases, are increasingly important aspects of the work of public health officers and medical providers. Diseases and the agents causing them are spatially and temporally distributed, and effective countermeasures rely on methods that can timely locate the foci of infection, predict the distribution of illnesses and their causes, and evaluate the likelihood of epidemics. These methods require the use of large datasets from ecology, microbiology, health and environmental geography. Geodatabases integrating data from multiple sets of information are managed within the frame of geographic information systems (GIS). Many GIS software packages can be used with minimal training to query, map, analyse and interpret the data. In combination with other statistical or modelling software, predictive and spatio-temporal modelling can be carried out. This paper reviews some of the concepts and tools used in epidemiology and parasitology. The purpose of this review is to provide public health officers with the critical tools to decide about spatial analysis resources and the architecture for the prevention and surveillance systems best suited to their situations.

A Comparison of Recreational- and Intermediate Survey-Grade GPS Units for Importing Data into GIS Software Packages

Global positioning systems (GPS) and Geographic Information Systems (GIS) have become common tools for Extension professionals. These systems vary in terms of accuracy and cost. GPS ranges from recreational-quality to survey-quality, with intermediate levels in between. As the user moves from recreational-quality to survey-quality, both accuracy and cost increase. We compare a recreational GPS unit (Garmin) and importing data into Google Earth software and an intermediate survey-grade GPS unit (Trimble Juno) and importing data into ArcMap GIS software. These represent two of the most common GIS choices available to natural resource professionals. Cost effectiveness will depend on accuracy requirements.

An Evaluation of Small Area Population Estimation Techniques Using Open Access Ancillary Data

National census data represent the “gold standard” for authoritatively portraying a country's residential population distribution, but their aggregated counts for fixed administrative areas present problems for many geographic information system (GIS) analyses. Intelligent areal interpolation algorithms assist by transferring data from one zonal system to another using ancillary data to improve accuracy. All areal interpolation methods make assumptions and generate errors, and performance varies with both specific location and the data inputs used. This study adds to our understanding of the relative merits of alternative methods by comparing dasymetric, street network, and surface‐based models interpolating across two spatial resolutions. It examines the importance of the ancillary data source used to drive the process, particularly the efficacy of open access products. Results from an empirical study show that interpolation accuracy is influenced by the choice of ancillary data input as well as the methodological approach adopted. The strongest overall performance is delivered by dasymetric mapping combined with open access data identifying the locations of buildings. Open access data sets offer considerable potential for widening the use of intelligent population interpolation tools, especially if plug‐in tools to execute these algorithms can be made available for commonly used GIS software packages.全国人口普查数据代表了一个国家居民人口分布权威描述的黄金标准，但以固定行政区域汇总的数据进行GIS分析则存在诸多问题。智能区域插值算法利用辅助数据将数据从一个区域系统转换至另一区域系统以提高数据精度。所有的区域插值方法都作出假设并产生误差，且插值性能随着具体位置和数据输入的变化而变化。本研究对密度、街道网络、基于区域模型在两种空间分辨率下插值结果进行比较，加强对于可选插值方法优缺点的理解。它检验了应用辅助数据源，尤其是开放获取数据源对于驱动这个过程的重要性。实证结果显示，插值精度受所选择的输入辅助数据和方法的影响。总体上最好的插值效果来自于采用分区密度图并结合开放获取数据识别建筑位置。尤其是当可以常用GIS软件包中以插件工具执行这些算法时，开放数据集可为拓展智能人口插值工具应用领域提供很高的可能。

An algorithm for generating geometric buffers for vector feature layers

The paper presents an algorithm for constructing geometric buffers for vector feature layers and dissolving those buffers using a sweep-line approach and vector algebra. The algorithm works by first constructing a geometric buffer for a vector feature layer, then dissolving each single geometric buffer for that feature layer, and finally dissolving the overlapping buffers of the entire layer. The algorithm has been implemented successfully in a commercial Geographical Information System software package.

Temporal Three-Dimensional Ontology for Geographical Information Science (GIS)—A Review

While the use of three-dimensional (3D) geographical information system (GIS) is becoming in rapid development and being used in various fields such as urban and regional planning, disaster management and planning, mobile navigation and etc., commercial and open source GIS software packages tend to offer 3D-GIS functionalities for their products. On the basis, GIS analysis functions are to provide information with respect to geographical location and by having 3D spatial data as an input, it will give advantages in providing horizontal position information. However, to analyze moving objects (temporal) in 3D seems not an easy task and not fully supported by current GIS platform packages. Previously in two-dimensional (2D) GIS practice, main issue addressed by researchers in managing temporal spatial objects is GIS packages were designed based on hardware and software constraints whereby it should be based on the temporal spatial objects ontology. Nowadays, the trend of managing temporal 3D data is via 3D spatial simulation or animation. This approach will not in assistance for GIS users in conducting spatial queries. Without having a suitable ontology and valid topological data structure for temporal 3D data, it will cause repetitive of temporal data (redundancy) and complications in executing spatial analysis in 3D environment. Therefore this paper focuses on the ontology for managing moving 3D spatial objects (i.e. air pollution, flood). The characteristics of moving objects were reviewed thoroughly by categorizing it based on its different appearances. Moreover, existing methods in managing temporal database were addressed and discussed for its practicalities. Another important aspect in managing temporal 3D objects is the implementation of topological data structures for 3D spatial objects were reviewed. In the last section of this paper it summarized the issues and further ideas towards implementing and managing temporal 3D spatial objects in GIS based on the Geoinformation Ontology (GeO).

Enhancing ArcGIS Decision Making Capabilities Using an Intelligent Multicriteria Decision Analysis Toolbox

Spatial decision making problems are multi-facetted challenges. Not only they often involve numerous technical requirements, but may also contain economic, social, environmental and political dimensions that may have conflicting values. Solutions for these problems involve highly complex spatial data analysis processes and frequently require advanced means to address physical suitability conditions while considering the multiple socio-economic variables. Geographic Information Systems (GIS) and Multicriteria Decision Making (MCDM) techniques are the most common tools employed to solve these problems, each of these tools has its own shortcoming and could not be used alone to reach an optimum solution. The need for combining the strengths of these techniques has prompted researchers to seek integration of GIS and MCDM. Most GIS software packages do not support MCDM such as ArcGIS ® which is a great tool for handling spatial analysis. However, it has limited capabilities of handling multicriteria decision problems. In the same time, decision makers need intelligent guidance for selecting a suitable MCDM technique for their decision situation because different MCDM techniques suit different kinds of decision situation. In this study, an intelligent ArcGIS extension (MCDM Analyst) is developed to enhance ArcGIS decision making capabilities and to help the GIS analysts to select and implement the suitable MCDM techniques for their problems. The component object model (COM) technology is used in designing and integrating this extension with ArcGIS to achieve software interoperability. A typical case study is presented to demonstrate the application of this extension.

Developing a Flow Mapping Module in a GIS Environment

The serious drawback of traditional flow mapping commonly representing geographical movement with straight lines of varying widths is a visual cluttering problem. To resolve these issues, several alternatives reducing the problem or enhancing pattern detection have been suggested. Despite being successful in some aspects, they have their shortcomings such as partial representation or misrepresentation of geographical movement and difficulty in interpreting visualized results. In addition, flow mapping functionality has yet to be fully implemented in modern geographic information systems (GIS) applications. Given these problems, this paper proposes the new designed symbols for improving the traditional flow mapping and develops a flow mapping module implementing them within a commercial GIS software package. Application results demonstrated that the developed module can represent gross, net, two-way and location-specific flows from a single dataset efficiently and can make better flow maps with the alternative symbols. The alternative symbols successfully reduced the visual overlap of symbols and improved the estimation of values.

GIS-based data model and tools for creating and managing two-dimensional cross sections

While modern Geographic Information Systems (GIS) software is robust in handling maps and data in plan view, the software generally falls short when representing features in section view. Further complicating the issue is the fact that geologic cross sections are often drawn by connecting a series of wells together that do not fall along a single straight line. In this case, the x-axis of the cross section represents the distance along the set of individual lines connecting the series of wells, effectively “flattening out” the cross section along this path to create a view of the subsurface with which geologists often work in printed folios. Even 3D-enabled GIS cannot handle this type of cross section. A GIS data model and tools for creating and working with two-dimensional cross sections are presented. The data model and tools create a framework that can be applied using ESRI's ArcGIS software, enabling users to create, edit, manage, and print two-dimensional cross sections from within one of the most well-known GIS software packages. The data model is a component of the arc hydro groundwater data model, which means all two-dimensional cross sections are inherently linked to other features in the hydrogeologic domain, including those represented by xyz coordinates in real world space. Thus, the creation of two-dimensional cross sections can be guided by or completely driven from standard GIS data, and geologic interpretations established on two-dimensional cross sections can be translated back to real world coordinates to create three-dimensional features such as fence diagrams, giving GIS users the capacity to characterize the subsurface environment in a variety of integrated views that was not possible before. A case study for the Sacramento Regional Model in California demonstrates the application of the methodology in support of a regional groundwater management plan.