340 research outputs found
Capabilities and limitations of methods for BRDF characterization in imaging spectrometer data
Recent activities in the hyperspectral imaging network (Hyper-I-Net): A European consortium fostering imaging spectroscopy research
On the verge of extinction - revision of a highly endangered Swiss alpine snail with description of a new genus, Raeticella gen. nov. (Gastropoda, Eupulmonata, Hygromiidae).
The phylogenetic status of the alpine land snail Fruticicolabiconica has remained questionable since it was described by Eder in 1917. Considered a microendemic species from mountain tops in Central Switzerland, the shell is specially adapted for life under stones. Herein, we show via molecular and anatomical investigations that F.biconica neither belongs to the land snail genus Trochulus, nor to any other genus within Trochulini, but rather warrants placement within the newly established genus Raeticella Kneubühler, Baggenstos & Neubert, 2022. Phylogenetic analyses reveal that R.biconica is clearly separated from Trochulus. These findings are supported by morphological investigations of the shell and genitalia
Coupling UAV and satellite data for tree species identification to map the distribution of Caspian poplar
Context
Mapping the distribution of species, especially those that are endemic and endangered like certain tree species, is a vital step in the effective planning and execution of conservation programs and monitoring efforts. This task gains even more significance as it directly contributes to forest conservation by highlighting the importance of species diversity.
Objectives
Our study objective was to assess the detection accuracy of a specific tree using different remote sensing sources and approaches.
Methods
Initially, individual trees were identified and classified using a canopy height model derived from UAV data. Next, we carried out the classification of satellite data within the Google Earth Engine. Lastly, we scaled the UAV-RGB dataset to match the spatial resolution of Sentinel-2, which was then employed to train random forest models using the multispectral data from Sentinel-2.
Results
For the UAV data, we achieved overall accuracies of 56% for automatically delineated tree crowns and 83% for manually delineated ones. Regarding the second approach using Sentinel-2 data, the classification in the Noor forest yielded an overall accuracy of 74% and a Kappa coefficient of 0.57, while in the Safrabasteh forest, the accuracy was 80% with a Kappa of 0.61. In the third approach, our findings indicate an improvement compared to the second approach, with the overall accuracy and Kappa coefficient of the classification rising to 82% and 0.68, respectively.
Conclusions
In this study, it was found that according to the purpose and available facilities, satellite and UAV data can be successfully used to identify a specific tree species
Weber
Qu'est-ce que la sociologie de Weber nous dit de sa conception de l'être humain? Comment serait réellement l'être humain, s'il existait comme il le théorise? Comment ferait un comédien qui aurait à le jouer dans une pièce de théâtre? Ce sont les questions, posées par les éditeurs du Dictionnaire des anthropologies, auxquelles cet article propose de répondre
Spectroradiometry as a tool for phenological characterization of agricultural crop stands
From the early days of remote sensing until today, there has been a wide range of applications of remote sensing data for agricultural management. Improvements in spatial,
spectral and temporal resolution of available data products together with precision agriculture have meant an increase in the availability of services and products that help to manage agricultural operation more efficiently and profitably. Imagebased remote sensing offers the potential to provide spatially and temporally distributed information for agricultural management. Remote sensing information can improve the capacity and accuracy of decision support systems (DSS) and agronomic models by providing accurate input information or as a means of within-season calibration or validation. Crop phenology is an important variable required by precision crop management systems (PCMS) in support of time-critical crop management (TCCM). Estimates of crop development, which are used for nutrient deficiencies detection, crop yield prediction or timing of forthcoming harvest are important in agricultural planning and policy making.
While the collection of information on the status of biophysical and biochemical characteristics of a crop canopy, that can be correlated to its phenology, is time consuming and limited to punctual measurements, remote sensing allows large and continuous radiometric measurements. Parameters retrievable by a remote sensing system must have an impact on the spectral signal of vegetation canopies. Biophysical parameters are easier to determine because they affect broader spectral regions, whereas biochemical concentrations are more difficult to assess since their spectral features are small and therefore only detectable by hyperspectral sensors.
In this paper, a methodology to track the main development stages of two cereals relevant for agricultural purposes and precision farming needs, based on hyperspectral data, is presented. An investigation of the suitability of four key parameters to track a crop stand’s vitality and an error assessment are performed. Leaf area index (LAI), fraction of absorbed photosynthetically active radiation (FAPAR), water content and chlorophyll content are defined as the main parameters reflecting vitality and therefore alter with the plants’ phenological stage
Tarde
Qu'est-ce que la psychologie sociale de Tarde nous dit de sa conception de l'être humain? Comment serait réellement l'être humain, s'il existait comme il le théorise? Comment ferait un comédien qui aurait à le jouer dans une pièce de théâtre? Ce sont les questions, posées par les éditeurs du Dictionnaire des anthropologies, auxquelles cet article propose de répondre
Dewey
Qu'est-ce que la philosophie de Dewey nous dit de sa conception de l'être humain? Comment serait réellement l'être humain, s'il existait comme il le théorise? Comment ferait un comédien qui aurait à le jouer dans une pièce de théâtre? Ce sont les questions, posées par les éditeurs du Dictionnaire des anthropologies, auxquelles cet article propose de répondre
Konzeptionen des Bösen bei Philon von Alexandrien
Das Dissertationsprojekt untersucht die Idee des Bösen bei Philon und kontextualisiert seine Deutungen dieses in der antiken Philosophie intensiv diskutierten Problems in der weiteren jüdischen und paganen Philosophie
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