TY - BOOK

T1 - Out of the darkness and into the light

T2 - the quest for fluorescence-based soil tracers

AU - Hardy, Robert

PY - 2016

Y1 - 2016

N2 - This thesis explores the use of fluorescent tracers to monitor the redistribution of soil at hightemporal and spatial resolutions. Soil redistribution happens on a second by second basiswith individual particles moving millimetres at a time. There are few, if any, existing tracingmethods which permit the monitoring of soil movements at temporal and spatial scales thatare commensurate with the scales at which these movements happen. This thesis charts thedevelopment of new tracing technologies that allow for the movement of soil to bemonitored at high spatial and temporal resolution, resolutions which are commensurate withthe movement of individual particles. This will allow for deeper insight into how soil movesand has a range of applications for fundamental soil movement studies to applied agriculturalinvestigations. In order to study the movement of clay a novel fluorescent clay tracer wascreated along with fluorescent imaging techniques which allowed for the movement of thistracer to be captured. The movement of larger soil particles is also important and by using acommercially available fluorescent tracer combined with fluorescent videography it waspossible to track the movement of individual soil particles across a soil surface during asimulated rainfall event. The movement of these particles was captured 50 times a secondwith sub-mm precision. A similar system was then developed for use in the field environmentand was demonstrated at field scale by monitoring the redistribution of a tracer across a soilsurface as a result of tillage. It was also possible to monitor the vertical redistribution of thetracer within the soil profile by digging soil pits. The methods detailed here show that it ispossible to gain much information about the redistribution (i.e. change in location) of soilacross a soil surface without the inconvenience, expense and system perturbation that iscaused by traditional sampling. Overall these methods demonstrate that it is possible for soiltracing to operate in a data rich environment providing new opportunities to develop,parameterise and evaluate soil movement models.

AB - This thesis explores the use of fluorescent tracers to monitor the redistribution of soil at hightemporal and spatial resolutions. Soil redistribution happens on a second by second basiswith individual particles moving millimetres at a time. There are few, if any, existing tracingmethods which permit the monitoring of soil movements at temporal and spatial scales thatare commensurate with the scales at which these movements happen. This thesis charts thedevelopment of new tracing technologies that allow for the movement of soil to bemonitored at high spatial and temporal resolution, resolutions which are commensurate withthe movement of individual particles. This will allow for deeper insight into how soil movesand has a range of applications for fundamental soil movement studies to applied agriculturalinvestigations. In order to study the movement of clay a novel fluorescent clay tracer wascreated along with fluorescent imaging techniques which allowed for the movement of thistracer to be captured. The movement of larger soil particles is also important and by using acommercially available fluorescent tracer combined with fluorescent videography it waspossible to track the movement of individual soil particles across a soil surface during asimulated rainfall event. The movement of these particles was captured 50 times a secondwith sub-mm precision. A similar system was then developed for use in the field environmentand was demonstrated at field scale by monitoring the redistribution of a tracer across a soilsurface as a result of tillage. It was also possible to monitor the vertical redistribution of thetracer within the soil profile by digging soil pits. The methods detailed here show that it ispossible to gain much information about the redistribution (i.e. change in location) of soilacross a soil surface without the inconvenience, expense and system perturbation that iscaused by traditional sampling. Overall these methods demonstrate that it is possible for soiltracing to operate in a data rich environment providing new opportunities to develop,parameterise and evaluate soil movement models.

U2 - 10.17635/lancaster/thesis/154

DO - 10.17635/lancaster/thesis/154

M3 - Doctoral Thesis

PB - Lancaster University

ER -