A preliminary assessment of the efficiency of using drones in land cover mapping

This study represents a preliminary assessment of the efficiency of drones in surveying land cover at both large (c: 10 ha) and smaller (1m2) spatial scales. A DJI Mavic 2 drone was used to image the entire area of study and an orthomosaic was produced. This was converted into a land cover map through k-means clustering, with k = 3, where `Vegetation', `Bedrock' and `Bare soil' corresponded to the land cover categories. Regions of interest (ROIs) were selected and sub- sequently surveyed from close range. The correspondence between predicted land cover (pLC) and observed land cover (oLC) was then assessed. On a large spatial scale, absolute correspondence was present between pLC and oLC. In terms of relative representation of land cover categories, `Vegetation' was the only significantly correlated category across pLC and oLC, whilst the analogous correlations for `Bedrock' and `Bare soil' were weaker. The lower correspondence between pLC and oLC for `Bedrock' and `Bare soil' was due to the low value of k = 3 in the k-means clustering algorithm. This constrains a mixture of land covers into just one land cover category, with consequent reduction of the correlation between pLC and oLC. The method's accuracy and cost-effectiveness were compared to that of standard methods for land cover surveying. The entire process, including verification and orthomosaic land cover map processing times, approximated 32 hours. Consequently, this method is much shorter than standard surveys, which take days or weeks, and also requires less manpower.peer-reviewe

A preliminary assessment of the efficiency of using drones in land cover mapping

This study represents a preliminary assessment of the efficiency of drones in surveying land cover at both large (c: 10 ha) and smaller (1m2) spatial scales. A DJI Mavic 2 drone was used to image the entire area of study and an orthomosaic was produced. This was converted into a land cover map through k-means clustering, with k = 3, where `Vegetation', `Bedrock' and `Bare soil' corresponded to the land cover categories. Regions of interest (ROIs) were selected and sub- sequently surveyed from close range. The correspondence between predicted land cover (pLC) and observed land cover (oLC) was then assessed. On a large spatial scale, absolute correspondence was present between pLC and oLC. In terms of relative representation of land cover categories, `Vegetation' was the only significantly correlated category across pLC and oLC, whilst the analogous correlations for `Bedrock' and `Bare soil' were weaker. The lower correspondence between pLC and oLC for `Bedrock' and `Bare soil' was due to the low value of k = 3 in the k-means clustering algorithm. This constrains a mixture of land covers into just one land cover category, with consequent reduction of the correlation between pLC and oLC. The method's accuracy and cost-effectiveness were compared to that of standard methods for land cover surveying. The entire process, including verification and orthomosaic land cover map processing times, approximated 32 hours. Consequently, this method is much shorter than standard surveys, which take days or weeks, and also requires less manpower.peer-reviewe

Chapter A drone’s eye view: A preliminary assessment of the efficiency of drones in mapping shallow-water benthic assemblages

The study assesses consumer drone efficiency for surveying shallow-water benthic cover. We hypothesised that using a drone would reduce duration, and manpower requirements, while increasing accuracy, relative to manual surveys. Results obtained during this study clearly indicated that automated drone surveys were faster and more accurate than manual survey methods under most circumstances. This result has important implications for the scientific and economic aspects of the process and would have a multiplicative effect in monitoring programs that require regular surveys

Hotspots of vegetation diversity within the maltese islands

Plant growth and diversity are controlled by a large number of factors, including water availability, light intensity, soil depth, pH and salinity, the level of exposure to wind and the degree of human disturbance. The interaction between these factors creates a set of local conditions that favour certain species over others. Malta’s valleys present a broad range of environmental conditions, where these factors vary dramatically over short distances. Changes in conditions along the length and across the width of the valleys interact with each other to form complex ecological units, capable of supporting a wide variety of plant species.peer-reviewe

Efecto del cambio del plan de estudio sobre el desempeño de los alumnos de Edafología

El curso de Edafología se encuentra ubicado en tercer año de la carrera de Ingeniería Agronómica. La promoción de los alumnos se realiza mediante tres modalidades: alumno regular sin examen final, con examen final y como alumno libre con examen final. En el año 2005 se estableció un nuevo plan de estudios, vigente, que produjo un cambio sustancial en la intensidad del curso de Edafología, hubo otro cambio como la eliminación de correlatividades de segundo grado. El objetivo de este trabajo fue evaluar el impacto del cambio de régimen de cursada cuatrimestral a anual sobre el desempeño de los alumnos de Edafología entre los años 2002-2011. Se analizó la cursada de 16 semanas, años 2004-2007, con la anual, de 22 semanas, años 2008-2011 y los finales de 10 años. El cambio de régimen de cursada, no ha podido revertir el comportamiento de la población estudiantil, manteniendo la tendencia hacia lo opción de promoción con examen final. Se observó una disminución en la presentación de los alumnos a los exámenes. La disminución de los alumnos que no promocionan Edafología podría atribuirse a que pueden terminar de cursar la integridad de las asignaturas de la carrera postergando ese requisito.Eje temático 4: La gestión curricular e institucional a - Planes de estudios: perfiles profesionales, flexibilización curricular, procesos de cambio y evaluación de la formación profesionalFacultad de Ciencias Agrarias y Forestale

Molecularly Imprinted Polymer as Selective Sorbent for the Extraction of Zearalenone in Edible Vegetable Oils

A method based on the selective extraction of zearalenone (ZON) from edible vegetable oils using molecularly imprinted polymer (MIP) has been developed and validated. Ultra-high-pressure liquid chromatography coupled with a fluorescence detection system was employed for the detection of zearalenone. The method was applied to the analysis of zearalenone in maize oil samples spiked at four concentration levels within the maximum permitted amount specified by the European Commission Regulation (EC) No. 1126/2007. As a result, the proposed methodology provided high recoveries (>72%) with good linearity (R2 > 0.999) in the range of 10-2000 μg/kg and a repeatability relative standard deviation below 1.8%. These findings meet the analytical performance criteria specified by the European Commission Regulation No. 401/2006 and reveal that the proposed methodology can be successfully applied for monitoring zearalenone at trace levels in different edible vegetable oils. A comparison of MIP behavior with the ones of QuEChERS and liquid-liquid extraction was also performed, showing higher extraction rates and precision of MIP. Finally, the evolution of ZON contamination during the maize oil refining process was also investigated, demonstrating how the process is unable to completely remove (60%) ZON from oil samples

Carpometacarpal subchondral cysts due to repetitive movements in shoemaker: A case report

Abstrac