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High-throughput phenotyping of large wheat breeding nurseries using unmanned aerial system, remote sensing and GIS techniquesHaghighattalab, Atena January 1900 (has links)
Doctor of Philosophy / Department of Geography / Douglas G. Goodin / Jesse A. Poland / Kevin Price / Wheat breeders are in a race for genetic gain to secure the future nutritional needs of a growing population. Multiple barriers exist in the acceleration of crop improvement. Emerging technologies are reducing these obstacles. Advances in genotyping technologies have significantly decreased the cost of characterizing the genetic make-up of candidate breeding lines. However, this is just part of the equation. Field-based phenotyping informs a breeder’s decision as to which lines move forward in the breeding cycle. This has long been the most expensive and time-consuming, though most critical, aspect of breeding. The grand challenge remains in connecting genetic variants to observed phenotypes followed by predicting phenotypes based on the genetic composition of lines or cultivars.
In this context, the current study was undertaken to investigate the utility of UAS in assessment field trials in wheat breeding programs. The major objective was to integrate remotely sensed data with geospatial analysis for high throughput phenotyping of large wheat breeding nurseries. The initial step was to develop and validate a semi-automated high-throughput phenotyping pipeline using a low-cost UAS and NIR camera, image processing, and radiometric calibration to build orthomosaic imagery and 3D models. The relationship between plot-level data (vegetation indices and height) extracted from UAS imagery and manual measurements were examined and found to have a high correlation. Data derived from UAS imagery performed as well as manual measurements while exponentially increasing the amount of data available. The high-resolution, high-temporal HTP data extracted from this pipeline offered the opportunity to develop a within season grain yield prediction model. Due to the variety in genotypes and environmental conditions, breeding trials are inherently spatial in nature and vary non-randomly across the field. This makes geographically weighted regression models a good choice as a geospatial prediction model. Finally, with the addition of georeferenced and spatial data integral in HTP and imagery, we were able to reduce the environmental effect from the data and increase the accuracy of UAS plot-level data.
The models developed through this research, when combined with genotyping technologies, increase the volume, accuracy, and reliability of phenotypic data to better inform breeder selections. This increased accuracy with evaluating and predicting grain yield will help breeders to rapidly identify and advance the most promising candidate wheat varieties.
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An assessment of using least squares adjustment to upgrade spatial data in GISMerritt, Roger, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2005 (has links)
The GIS Industry has digitised cadastre from the best available paper maps over the last few decades, incorporating the inherent errors in those paper maps and in the digitising process. The advent of Global Positioning Systems, modern surveying instruments and advances in the computing industry has made it desirable and affordable to upgrade the placement, in terms of absolute and relative position) of these digital cadastres. The Utility Industry has used GIS software to place their assets relative to these digital cadastres, and are now finding their assets placed incorrectly when viewed against these upgraded digital cadastres. This thesis examines the processes developed in the software program called the ???Spatial Adjustment Engine???, and documents a holistic approach to semi-automating the upgrading of the digital cadastre and the subsequent upgrading of the utility assets. This thesis also documents the various pilot projects undertaken during the development of the Spatial Adjustment Engine, the topological scenarios found in each pilot, their solution, and provides a framework of definitions needed to explore this field further. The results of each pilot project are given in context, and lead to the conclusions. The conclusions indicate the processes and procedures implemented in the Spatial Adjustment Engine are a suitable mechanism for the upgrade of digital cadastre and of spatially dependant themes such as utility assets, zoning themes, annotation layers, and some road centreline themes.
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An assessment of using least squares adjustment to upgrade spatial data in GISMerritt, Roger, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2005 (has links)
The GIS Industry has digitised cadastre from the best available paper maps over the last few decades, incorporating the inherent errors in those paper maps and in the digitising process. The advent of Global Positioning Systems, modern surveying instruments and advances in the computing industry has made it desirable and affordable to upgrade the placement, in terms of absolute and relative position) of these digital cadastres. The Utility Industry has used GIS software to place their assets relative to these digital cadastres, and are now finding their assets placed incorrectly when viewed against these upgraded digital cadastres. This thesis examines the processes developed in the software program called the ???Spatial Adjustment Engine???, and documents a holistic approach to semi-automating the upgrading of the digital cadastre and the subsequent upgrading of the utility assets. This thesis also documents the various pilot projects undertaken during the development of the Spatial Adjustment Engine, the topological scenarios found in each pilot, their solution, and provides a framework of definitions needed to explore this field further. The results of each pilot project are given in context, and lead to the conclusions. The conclusions indicate the processes and procedures implemented in the Spatial Adjustment Engine are a suitable mechanism for the upgrade of digital cadastre and of spatially dependant themes such as utility assets, zoning themes, annotation layers, and some road centreline themes.
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