Handheld Global Positioning System Research Articles

Assessment of road infrastructure using remote sensing and GIS methodology for monitoring the condition of paved and unpaved roads

This research primarily aims to develop a method in which road distress can be identified at early stage so that it could be maintained and fixed early thus avoiding critical damage. The primary source of data for the project was obtained by field survey with the use of vehicle and a handheld GPS to obtain the coordinates of each distress and a digital camera was used to take the pictures of the distress. The secondary sources of data include the Google Earth Imagery and the Remote sensing data. The approach adopted in this work involves obtaining the Global Positioning System (GPS) and the photographs of each distress noticed on the road, and then attaching the photographs to the classified map. The study was conducted in Yewa South Local Government in Ogun State in Nigeria which cover an area of 656,54 sqkm with population of 168,850 at the 2006 census. The study area has a total road length of 893.017 km. Assessment of road infrastructure using remote sensing and ArcGIS Geodatabase methodology for monitoring the condition of paved and unpaved road is an efficient approach utilized in management, planning and subsequent development of the road network in the study area.

Assessment of Community-led Total Sanitation Sustainability in Ejigbo Local Government Area of Osun State, Nigeria

Nigeria is among the nations of the world with the highest number of people practising Open Defecation. This study among others assessed the level of community-led total sanitation (CLTS) in the selected triggered communities and focused on the rationale for the reversion of CLTS programme implemented in some of some rural communities with poor sanitation coverage in Ejigbo Local Government Area of Osun state, Nigeria, with the technical and financial support of donor agencies. The qualitative, semi-structured questionnaires were administered in 296 households in 41 selected communities. Spatial positioning of communities and water points coordinates were collected through the use of a hand-held Global Positioning System- GPS model etrex 10 GARMIN to produce a digital map through the Arc view Geographical Information System software. Two batches of CLTS were conducted in the Local Government Area across 182 communities in 2006 and 2012 with and without subsidy. Communities were triggered and declared open defecation free while some were certified ODF. The majority (75.7%) of the respondents reverted to OD as a result of caved-in of pit latrine due to the use of log of wood, wooden slab as platform over the pit. 5.1% of the respondents improved on CLTS latrine 81.7% of household used the latrine for just two years before defectiveness set in. All respondents agreed to have benefited in the CLTS programme and were willing to return to construct durable latrine provided they get a subsidy or are financially buoyancy. This study revealed that emphasis was on latrine construction while other components of environmental sanitation were not properly addressed as any scalability was near to nothing. Monitoring and follow up was found to be weak among the stakeholders.

Spatial variations of women\u2019s home delivery after antenatal care visits at lay Gayint District, Northwest Ethiopia

BackgroundHome delivery is the most frequent childbirth practice in Ethiopia and brings health risks for many mothers and their babies which in turn affecting the whole families. Characterizing the spatial variations and the associated factors of home deliveries after antenatal care visit is necessary to prioritize risks and facilitate geographically based interventions.MethodA community-based cross-sectional study design was carried out between February and March 2016. A total of 528 women who had just given birth were interviewed face-to-face using a questionnaire. Geo-referenced data were collected using a handheld global positioning system (GPS). The Bernoulli model was applied using the SatScan ™ software to analyze the purely spatial clusters of home deliveries. ArcGIS version 10.1 was used to visualize clusters of home delivery.ResultsThe overall proportion of home deliveries was 278(52.7%), and home deliveries had spatial variations. A primary cluster [LLR = 14.54, p < 0.001] was detected in village of Safida Giorgis. Secondary clusters were detected in Checheho [LLR = 9.17, p < 0.05] and ZurAmba [LLR = 8.51, p < 0.05]. Predictors for home delivery included the distance between the health extension worker’s and mother’s house [AOR = 2.2, 95% CI: 1.1, 4.3], residence [AOR = 3.8, 95% CI: 1.3, 10.9], source of information for ANC [AOR = 0.3, 95% CI: 0.13, 0.7], ANC visits [AOR = 6.1, 95% CI:1.9, 19.3], health education [AOR = 3.4, 95% CI: 1.5, 7.4], decision on place of delivery [AOR = 0.3, 95% CI: 0.1, 0.8], and knowledge on place of delivery [AOR = 0.04, 95% CI: 0.0, 0.1].ConclusionThe proportion of home delivery after ANC visit was decreasing compared to other studies conducted in the region. In addition, spatial variations of home delivery were observed in the study area. Promoting women’s education and behavioral change communication at the grass root level, provision of the services both at home and health facilities and improving the quality and capacity of the health providers are some of the recommendations forwarded.

Compact broadband dual‐band circularly polarised antenna for universal UHF RFID handheld reader and GPS applications

This study introduces a simple, compact broadband dual-band circularly polarised slot antenna suitable for the use in the compact universal ultra-high frequency (UHF) radio-frequency identification (RFID) reader devices and Global Positioning System (GPS) applications. The proposed antenna is fed using an open-end coplanar waveguide with an inverted `L' structure. To realise a broadband circular polarisation and good impedance matching, an inverted L-shaped strip line is inserted adequately into a square slot at the right centre of the slot toward the slot centre. The experimental results demonstrate that the proposed antenna exhibits a 10 dB return loss bandwidth of 552 MHz (716-1268 MHz) and 3-dB axial ratio (AR) bandwidth of 564 MHz (824-1388 MHz). Additionally, the antenna gains are 3.8 and 4.29 dBi throughout UHF RFID band and GPS band, respectively. The proposed antenna has a wide AR bandwidth, a compact size, and a simple structure. Furthermore, the proposed antenna is printed on one substrate layer with an overall size of 112 × 112 × 1.6 mm 3 , which makes it more practical for universal UHF RFID handheld readers and GPS applications.

Land use\u2212land cover changes and Mopani worm harvest in Mangwe District in Plumtree, Zimbabwe

BackgroundMopani worms have been considered a critical food security resource as people living in Mopani woodlands depend on the worms both as a food source and as an income generating resource. These become a readily available substitute if agriculture fails and droughts loom. However the yields from these worms have been dwindling over the years and this has been associated with land use−land cover changes as the worms depend on vegetation. This research sought to investigate the relationship between land use−land cover changes and Mopani worm harvests in Mangwe District in Plumtree from the period 2007 to 2016 in Zimbabwe.MethodsSatellite imagery was collected using LandSat 5 and LandSat 8 satellite and then classified using the Semi-Automatic Classification plugin in Quantum Geographic Information System to identify trees, dams, bare soil and settlements. Thematic maps were then produced and used to quantify extent of Land Use–Land Cover changes in the period from 2007 to 2016. Ground control data was collected using hand held Global Positioning System. Harvests trends (and reasons thereof) were estimated through usage of interviewer administered questionnaires on selected Mopani worm harvesters and harvest data kept by the community leaders.ResultsResults showed that settlements and bare soil cover had greatly increased from 2007 to 2016. There was a significant decline on vegetation cover from 2007 to 2016. There was also decline in the Mopani worm harvest over the years. Reasons for reduction of harvest were cited as deforestation, drought, overharvesting, cooking with lids on and occurrence of veld fires.ConclusionsFindings of this study highlight that land use−land cover changes impacted negatively on Mopani worm harvests over the period 2007 to 2016. It is also of paramount importance to note that major reasons for this decline has been associated with Land Use changes that are associated with human activities. There is need for Natural Resource Conservation Agencies to embark on awareness campaigns to encourage reforestation and also control cutting down of Mopani woodlands. Research needs to be conducted to determine the association between cultural beliefs and Mopani worm conservation and utilisation.

GIS Based Appraisal of Waste Disposal for Environmental Assessment and Management in Mainland Area of Lagos State, NG

An appraisal of Waste disposal for environmental assessment and management in Lagos Mainland of Lagos state using the GIS has been carried out. GIS has been a veritable tool for analyzing, storing, querying, capturing, displaying and managing of Geographic information or data. This paper addressed the usefulness of Geographic information system applications in Waste disposal distribution and in management. The coordinates of the existing waste dump were collected through field survey and a Garmin 78Sc hand held Global positioning system (GPS) receiver was used in the coordinate acquisition. The result of the field observations and analysis showed that the GIS can be used to efficiently monitor waste disposal location, Scheduling of Waste-Bin and this can invariably be used for proper planning in environmental sanitation, assessment and management holistically. This study shows that the use of Geographic Information system cannot be overemphasized in the spatial mapping of solid waste disposal for environmental management and sanitation assessment. Keywords: GIS, Spatial Mapping, GPS, Waste Disposal, Lagos Mainland.

Managing Filling Stations Spatial Database Using an Innovative GIS Tool – Case Study Afipko City in Nigeria

With the Nigeria economy and her citizens over reliance on crude oil and its refined products, the use of petrol, diesel and kerosene in fuelling of generators and automobiles or for domestic cooking becomes very essential. Hence, constant visit to filling stations is necessary at one time or the other. This has in turn enthused the siting of so many filling stations and one is forced to wonder if they all complied with the standards required for their establishment. The question of where to buy fuel and which filling station is sited short of the regulatory standards can be appropriately answered using Geographic Information System (GIS). This study focuses on analysing the location of filling stations within Afikpo, in Ebonyi State Nigeria against the laws/regulations guiding their establishment. The coordinates of the filling stations were acquired with a handheld Global Positioning System (GPS) receiver and plotted on a georeferenced map in ArcMap environment of ArcGIS 10.2 software. All the analyses were performed in the ArcMap environment using spatial analyst, spatial statistics and proximity tools available in the software. The findings revealed that the filling stations are spatially distributed in a dispersed pattern. The results of the analysis reveals that 44.4% of the filling stations did not meet the criteria of 15 meters minimum distance from the pump to the edge of the road. 22.2% of the filling stations were sited too close (lesser than 100 meters) to a health care centre. 66.7 % % did not meet the criteria of 400 meter minimum distance to other stations when located on the same road side (with no road separation). This database created on filling stations provides a platform to help policy makers (regulatory agencies) in planning, management and effective monitoring/supervision. It is there recommended that the regulatory bodies should be proactive in the discharge of their duties.

Study of potential environmental factors predisposing ewes to subclinical mastitis in Greece.

Objectives of the work presented herewith were to investigate association of prevalence of subclinical mastitis with environmental (climatic and topographic) factors and to identify factors potentially predisposing ewes to the disease. Milk samples were collected from 2198 sheep in 111 farms, in all 13 administrative regions of Greece, for bacteriological and cytological examination. Data on farm location were collected in the field using hand-held Global Positioning System Garmin units. The geo-references were resolved to specific farm level. Prevalence of subclinical mastitis was 0.260. Main aetiological agents were staphylococci (Staphylococcus aureus and coagulase-negative species), which accounted for 0.699 of all isolates recovered. In a multivariable mixed-effects analysis, the two environmental variables found to be associated with increased prevalence of subclinical mastitis were the minimum temperature of coldest month (coefficient: -0.084 ± 0.033, P = 0.014) and the mean temperature for 30 days prior to sampling date (coefficient: 0.031±0.014, P = 0.029).

Use of geographical information system and ecological niche modelling for predicting potential space distribution of subclinical mastitis in ewes

Objective was to recognise areas potentially of high risk for increased frequency of subclinical mastitis in ewes. Milk samples were collected, for bacteriological and cytological examination, from 2198 clinically healthy ewes in 111 farms in all administrative regions of Greece. Data on farms were located in the field using hand-held Global Positioning System Garmin units. Collected data were analysed by an Ecological Niche Model under the framework of a geographic information system. Two separate analyses were performed: one for subclinical mastitis independently of causal agent (prevalence in population sampled: 0.260) and one for subclinical mastitis caused specifically by slime-producing staphylococci (prevalence in population sampled: 0.153). A model was constructed in which sheep farms were divided into two clusters, according to prevalence of subclinical mastitis: farms in the upper three quartiles of prevalence were used as occurrence points for the Ecological niche modelling procedure (‘infected farms’); farms in the lower quartile of prevalence within each category were (pseudo)negative points. Significant differences in environmental parametres prevailing in locations of farms into the study, were identified for up to 13 parametres between locations of farms according to management system applied in farms. When farms in each management system were considered separately, differences became evident between farms in each management system, as well as between the two infections. The factor with the highest relative contribution in the analyses was the distance from other sheep farms; other factors also of importance in the predictive models were the altitude, the maximum temperature of warmest month and the total precipitation of driest month. Verification of the model revealed that ≥ 0.760 of infected farms’ were located in areas predicted as high risk for prevalence of subclinical mastitis or slime staphylococcal subclinical mastitis. The paper describes for the first time potential association of mastitis with environmental factors and presents predictive models for mastitis in ewes taking into account environmental parametres.

Integrating Drone Technology with GPS Data Collection to Enhance Forestry Students Interactive Hands-On Field Experiences

Undergraduate students pursuing a Bachelor of Science in Forestry (BSF) at Stephen F. Austin State University (SFA) within the Arthur Temple College of Forestry and Agriculture (ATCOFA) attend an intensive 6-week hands-on instruction in applied field methods. The second week of field station is focused on land measurement activities to introduce students to practical, hands-on, and technology based ways to survey forest boundaries. On Monday of the second week students are introduced to the concepts of how to use a handheld compass to navigate from point to point, use a consumer-grade handheld Global Positioning System (GPS) unit for collecting the geographic coordinates of given locations, use a GPS unit to calculate the area of a forest opening, use a GPS unit to walk and record a forest hiking trail, and evaluate the accuracy of their GPS derived locations via a Root Mean Square Error (RMSE) analysis. RMSE analysis between a students collected geographic coordinates and the instructors collected geographic coordinates indicated that the students were sufficient in correctly recording the geographic coordinates of point, line, and polygon features identified in the field. Grades on the student submitted reports summarizing Monday’s activities resulted in 33 of 56 students (59.0%) receiving a high A, 14 of 56 students (25.0%) receiving a low A, and 9 of 56 students (16.0%) receiving a high B indicating that the interactive hands-on nature of ATCOFA’s field station is effective at providing students with real-world applications whereby they will be ready to make a difference the day after graduation. Interactive drone imagery and video integrated into the daily activities in the field to enhance a student’s understanding of their specific objectives provided the students in the field with a bird’s eye perspective of the landscape to aid their understanding and planning of the field tasks assigned. In conclusion, employers can have confidence that when hiring recent BSF graduates from ATCOFA that the students have been introduced to geospatial technologies within a proven one-on-one instruction methodology designed to increase cognitive retention and can traverse from location to location accurately and record the geographic coordinates of earth surface features correctly.

Geographic mapping of tube wells and assessment of saltwater intrusion in the coastal areas of la union

A large number of coastal aquifers are threatened by saltwater intrusion. Over-abstraction due to high demands for domestic water supply is the main cause of saltwater intrusion. This can also be accelerated by the rise in sea level due to climate change and global warming. This reduces the fresh groundwater resources. With the impact of sea level rise and over-pumping combined together, the problem becomes even more serious.A large part of the province of La Union in the Ilocos Region, Northern Philippines is lying along the coastline, with its community stakeholders depending on wells for their source of water. Considering the safety of users, the study aimed to determine the incidence of saltwater intrusion in the coastal communities of La Union. In this study, the descriptive-qualitative research design was used. A questionnaire was formulated to determine the perceptions of the community stakeholders on the quality of water they are using but their responses were verified by the use of salinity meter to test the actual water salinity from the tube wells. Through the use of handheld Global Positioning System (GPS), the geographical coordinates depicting the location of the wells included in the study were identified. There was a total of 42 barangays selected as study sites. Using quota sampling, a total of 420 tube wells were subjected to analysis. A geographical map of tube wells showing the affected areas served as an output of the study.The research revealed that salt intrusion already exists into tube wells along coastal areas of La Union. Community stakeholders had already resorted to other sources/means for their water consumption.

Comparison of different GPS's used in different areas in our country's forestry

Aim of study: Terrestrial measurements have an important place in the production of spatial databases for use in forestry activities in Turkey. Terrestrial methods develop in parallel to the advancing technology while the mechanical measuring devices used in the past are replaced by computer-assisted digital measuring devices.Area of study:. The Forestry Faculty area of Istanbul University at the European side of province of Istanbul was determined as study area for the present study.Material and Methods: Global positioning systems (GPS) developed to collect satellite-based spatial data are among the devices derived from this technology. This study explored the possibilities to use this technology for forestry purposes and the performance of hand held Global Positioning System, Differential Global Positioning System (DGPS), DGPS-Continuously Operating Reference Stations (CORS) and Total Station on the areas representing the very closed forest area, open area and forest boundary selected for the study was assessed.Main results: According to the results, DGPS CORS type GPS is the most accurate one for all three areas types. It was most accurate in closed forest area as the error margin in dense foliage was 3,41 m in horizontal and 3,88 m in vertical; 0,06 m in horizontal and 0,05 m in vertical for open area; 0,62 m in horizontal and 1,16 m in vertical for forest boundary.Research highlights: It is predicted that DGPS CORS systems to be preferred in forestry operations requiring high sensitivity, whereas usage of hand held GPS systems for time saving.

Applicability of Surveying Professional Practice in Land Use Planning for Community Land Conflict Extrication in Mbeya Rural Area

Land conflict has been noted to be an intervening phenomenon for quite longer as it has caused many misunderstanding, competition and violence between different society group as well as adjacent land owners. Different factors has been noted in different literatures related to land conflict like scarcity of resource (water, land, pasture), policies, politics on land decision matters, land law, irregularities on land allocation procedures etc. This study explains the applicability of surveying professional practice in land use planning for community land conflict extrication in Mbeya rural area. Three districts were randomly selected as a pilot survey area for the study. Land officer, land surveyor and planners were considered as important participants in land related issues as well as participating in land conflict extrication. The study revealed that poor procedure on land planning and demarcation, poor technical survey skills, poor adherence to survey practice as well as poor participation of surveyors from inception and or during base map and or town planning drawing preparation mostly results to poor and or incorrect drawing which would always be used by the planner for land use planning. However the use of inaccurate surveying equipment like a hand held Global positioning system (GPS) which has the accuracy of up to ±3m was noted to facilitate encroachment and hence the land conflict between neibour if not well and early settled. Nevertheless the applicability of the surveying professional practice was considered to resolve the problems. A well trained and experienced surveyor should be engaged during preliminary spatial data capture for base map and or town planning drawing preparation, a work which to-date at large is being done by the planner who in reality lacks the surveying professional practice in either using surveying equipment or data analysis something in turn leads to prolonged land conflict.

Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana.

The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn). Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area.

Soil organic carbon mapping using remote sensing techniques and multivariate regression model

Soil organic carbon (SOC) is an important aspect of soil quality and plays an imperative role in soil productivity in the agriculture ecosystems. The present study was applied to estimate the SOC stock using space-borne satellite data (Landsat 4–5 Thematic Mapper [TM]) and ground verification in the Medinipur Block, Paschim Medinipur District and West Bengal in India. In total, 50 soil samples were collected randomly from the region according to field surveys using a hand-held Global Positioning System (GPS) unit to estimate the surface SOC concentrations in the laboratory. Bare soil index (BSI) and normalized difference vegetation ndex (NDVI) were explored from TM data. The satellite data-derived indices were used to estimate spatial distribution of SOC using multivariate regression model. The regression analysis was performed to determine the relationship between SOC and spectral indices (NDVI and BSI) and compared the observed SOC (field measure) to predict SOC (estimated from satellite images). Goodness fit test was performed to determine the significance of the relationship between observed and predicted SOC at p ≤ 0.05 level. The results of regression analysis between observed SOC and NDVI values showed significant relationship (R2 = 0.54; p < 0.0075). A significant statistical relationship (r = −0.72) was also observed between SOC and BSI. Finally, our model showed nearly 71% of the variance of SOC distribution could be explained by SOC and NDVI values. The information from this study has advanced our understanding of the ongoing ecological development that affects SOC dissemination and might be valuable for effective soil management.

Association between full service and fast food restaurant density, dietary intake and overweight/obesity among adults in Delhi, India

BackgroundThe food environment has been implicated as an underlying contributor to the global obesity epidemic. However, few studies have evaluated the relationship between the food environment, dietary intake, and overweight/obesity in low- and middle-income countries (LMICs). The aim of this study was to assess the association of full service and fast food restaurant density with dietary intake and overweight/obesity in Delhi, India.MethodsData are from a cross-sectional, population-based study conducted in Delhi. Using multilevel cluster random sampling, 5364 participants were selected from 134 census enumeration blocks (CEBs). Geographic information system data were available for 131 CEBs (n = 5264) from a field survey conducted using hand-held global positioning system devices. The number of full service and fast food restaurants within a 1-km buffer of CEBs was recorded by trained staff using ArcGIS software, and participants were assigned to tertiles of full service and fast food restaurant density based on their resident CEB. Height and weight were measured using standardized procedures and overweight/obesity was defined as a BMI ≥25 kg/m2.ResultsThe most common full service and fast food restaurants were Indian savory restaurants (57.2%) and Indian sweet shops (25.8%). Only 14.1% of full service and fast food restaurants were Western style. After adjustment for age, household income, education, and tobacco and alcohol use, participants in the highest tertile of full service and fast food restaurant density were less likely to consume fruit and more likely to consume refined grains compared to participants in the lowest tertile (both p < 0.05). In unadjusted logistic regression models, participants in the highest versus lowest tertile of full service and fast food restaurant density were significantly more likely to be overweight/obese: odds ratio (95% confidence interval), 1.44 (1.24, 1.67). After adjustment for age, household income, and education, the effect was attenuated: 1.08 (0.92, 1.26). Results were consistent with further adjustment for tobacco and alcohol use, moderate physical activity, and owning a bicycle or motorized vehicle.ConclusionsMost full service and fast food restaurants were Indian, suggesting that the nutrition transition in this megacity may be better characterized by the large number of unhealthy Indian food outlets rather than the Western food outlets. Full service and fast food restaurant density in the residence area of adults in Delhi, India, was associated with poor dietary intake. It was also positively associated with overweight/obesity, but this was largely explained by socioeconomic status. Further research is needed exploring these associations prospectively and in other LMICs.

Spectral similarity approach for mapping turbidity of an inland waterbody

Turbidity is an important quality parameter of water from its optical property point of view. It varies spatio-temporally over large waterbodies and its well distributed measurement on field is tedious and time consuming. Generally, normalized difference turbidity index (NDTI), or band ratio, or regression analysis between turbidity concentration and band reflectance, approaches have been adapted to retrieve turbidity using multispectral remote sensing data. These techniques usually provide qualitative rather than quantitative estimates of turbidity. However, in the present study, spectral similarity analysis, between the spectral characteristics of spaceborne hyperspectral remote sensing data and spectral library generated on field, was carried out to quantify turbidity in the part of Chilika Lake, Odisha, India. Spatial spectral contextual image analysis, spectral angle mapper (SAM) technique was evaluated for the same. The SAM spectral matching technique has been widely used in geological application (mineral mapping), however, the application of this kind of techniques is limited in water quality studies due to non-availability of reference spectral libraries. A spectral library was generated on field for the different concentrations of turbidity using well calibrated instruments like field spectro-radiometer, turbidity meter and hand held global positioning system. The field spectra were classified into 7 classes of turbidity concentration as <5, 5–10, 10–15, 15–25, 25–45, 45–100 and >100NTU for analysis. Analysis reveal that at each location in the lake under consideration, the field spectra matched with the image spectra with SAM score of 0.8 and more. The observed turbidity at each location was also very much falling in the estimated turbidity class range. It was observed that the spectral similarity approach provides more quantitative estimate of turbidity as compared to NDTI.

An adaptive household sampling method for rural African communities

Investigators working in rural communities and small towns in Africa face many obstacles to obtaining a random and representative sample of households for their research. The civic infrastructure used as the building blocks of survey sampling in developed countries are mostly absent in rural Africa. The purpose of the study described in this paper was to pilot an innovative and cost-effective approach to household sampling designed to generate probability samples representative of the socio-economic diversity of the small town of Berekuso, in the Eastern Region of Ghana, without relying on existing census data, household registers, or a regular layout of roads and dwellings. Utilizing Google Earth images and a Graphical Information System (GIS) map of Berekuso, sampling units were defined as 15-degree wedge-shaped sectors radiating from the center of the original township. All households within randomly selected sectors were surveyed, and based on a household classification scheme, each household type was identified. Additional sectors were randomly selected and surveyed in sequence until no new household types were identified – a notion recognized by laboratory scientists as an ‘end point’. The adaptive sampling strategy was cost and time effective: freely available versions of Google Earth and QGIS software were employed along with inexpensive handheld Global Positioning System (GPS) devices; a total of 57 households were surveyed by teams of two enumerators over three consecutive Sundays. The survey method yielded a probability sample that is representative of the socioeconomic diversity of Berekuso, and produced generalizable results for median household size, median age of residents, sources of potable water and toilet types, among others. For example, based on the results of the survey, a 95% confidence interval estimate of the proportion of residents of Berekuso under the age of 20 years is between 0.49 and 0.58. These figures are consistent with results of Ghana’s 2010 census which pegged the proportion of the population of the Eastern Region under the age of the 20 years at 0.49. The authors believe that the methodology described in this paper may be applicable to household research in many rural African villages and small towns where little civic infrastructure exists to create more traditional sampling frames. Key words : Google Earth, area sampling, household survey, impact evaluation, wealth ranking

Modeling Vegetation Lifeforms Abundance based on &amp;lt;i&amp;gt;Epigeal Termitaria&amp;lt;/i&amp;gt; Physiography and Altitude in Tropical Savannah of Katolo Sub-Location, Kisumu County

Termite mounds are major sites of functional heterogeneity in the tropical ecosystems globally; through their prodigious influence on vegetation and soil perturbation. They aid soil aeration, water infiltration and catabolism of vegetative matter into nutrient rich humus. There is no documentation of a model for prediction of vegetation lifeforms with respect to mound basal radii, heights and altitude. Objective of this study was therefore to develop a model for rapid prediction of vegetation lifeforms (trees, shrubs, lianas and grass) abundance based on physiography (basal radii and heights) and altitude of the termite mounds. Study population of the mounds was unknown. Cross sectional research design was used. Saturated sampling was done where sixty accessible termite mounds were studied. Both basal radii and heights of termite mounds were measured using 50 m tape measure or hand-held inclinometer. Altitude data were captured by hand-held Global Positioning System (GPS). Trees, shrubs and lianas were identified visually and counted on the mounds while grass abundance was estimated using 0.3 m by 0.3 m quadrat on every termitarium. Multiple Linear Regressions were done to model vegetation lifeforms abundance based on termite mound basal radius, height and altitude. Results indicated that predicted MLR significantly (p ≤ 0.05) predicted trees, shrubs and lianas but not grass abundance. Predicted trees abundance = -89.2587 + 10.46157 (radius (m)) - 4.96989 (height (m)) + 0.074074 (altitude (m)), predicted shrubs abundance = 19.26065 + 6.780626 (radius (m)) - 6.09157 (height (m)) - 0.00822 (altitude (m)) and predicted lianas abundance = -24.9345 + 5.881659 (radius (m)) - 0.68423 (height (m)) + 0.020729 (altitude (m)). This study demonstrated significant effect of termite mound physiography on vegetation lifeforms abundance as well as developed a model for rapid prediction of their abundance on termite mounds.

Evaluating the Impacts of Hunting Paths on Northern Bobwhite Survival, Economic Costs, and Hunter Satisfaction

The amount and spatial configuration of habitat is known to influence the abundance, movements, resource use, and persistence of many species. As such, land managers must be judicious in their application of management actions to minimize its impact on wildlife while concurrently providing recreational opportunities. Mowing or roller-chopping is a common management technique implemented on intensively managed northern bobwhite (Colinus virginianus) plantations to increase hunter accessibility, provide travel corridors for pointing dogs, manage vegetation succession, among other benefits. Managers typically create hunting paths in a grid pattern at 30 ft spacing resulting in approximately 35% of vegetation removed prior to hunting season. However, the optimal spacing for paths is unknown and some concern exists over the presence of paths in general as they may facilitate predation. Our objectives were to determine how different densities of paths (i.e., reduced cover and increased edge) impacted northern bobwhite survival, quantify the costs per hectare of paths, and determine hunter satisfaction. We developed two path treatments (30 ft and 90 ft spacing) and a control (no paths) on Tall Timbers Research Station in Leon County, Florida. We radio-tagged a subset of northern bobwhites (n = 150), equally distributed within each treatment, and monitored survival in each treatment using radio-telemetry during the non-breeding season (October through April) in 2013-2016. We used Burnham’s joint model within program MARK to compare survival of radio-tagged bobwhites among treatment groups. We analyzed data collected from a hand-held global positioning system used to delineate paths during creation to compute implementation cost. Hunter satisfaction was assessed using a pre- and post-hunt survey. Optimization will be used to determine which treatment achieves the greatest utility under current management objectives. Results of this research will provide managers information to make informed decisions about the implementation of hunting paths under various management scenarios.