distribution maps
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2022 ◽  
Carmelo Bonannella ◽  
Tomislav Hengl ◽  
Johannes Heisig ◽  
Leandro Parente ◽  
Marvin N Wright ◽  

Abstract Paper describes a data-driven framework based on spatio-temporal ensemble machine learning to produce distribution maps for 16 forest tree species (Abies alba Mill., Castanea sativa Mill. , Corylus avellana L., Fagus sylvatica L., Olea europaea L., Picea abies L. H. Karst., Pinus halepensis Mill., Pinus nigra J. F. Arnold, Pinus pinea L., Pinus sylvestris L., Prunus avium L., Quercus cerris L., Quercus ilex L., Quercus robur L., Quercus suber L. and Salix caprea L.) at high spatial resolution (30 m). Tree occurrence data for a total of 3 million of points was used to train different Machine Learning (ML) algorithms: random forest, gradient-boosted trees, generalized linear models, k-nearest neighbors, CART and an artificial neural network. A stack of 585 coarse and high resolution covariates representing spectral reflectance (Landsat bands, spectral indices; time-series of seasonal composites), different biophysical conditions (i.e. temperature, precipitation, elevation, lithology) and biotic competition (other species distribution maps) was used as predictors for realized distributions, while potential distribution was modelled with environmental predictors only. Logloss and computing time were used to select the three best algorithms to train an ensemble model based on stacking with a logistic regressor as a meta-learner for each species. High resolution (30 m) probability and model uncertainty maps of realized distribution were produced for each species using a time window of 4 years for a total of 6 distribution maps per species for the studied period, while for potential distributions only one map per species was produced. Results of spatial cross validation show that Olea europaea and Quercus suber achieved the best performances in both potential and realized distribution, while Pinus sylvestris and Salix caprea achieved the worst. Further analysis shows that fine-resolution models consistently outperformed coarse resolution models (250 m) for realized distribution (average decrease in logloss: +53%). Realized distribution models achieved higher predictive performances than potential distribution ones. Importance of predictor variables differed across species and models, with the green band for summer and the NDWI and NDVI for fall for realized distribution and the diffuse irradiation and precipitation of the driest quarter being the most important and frequent for potential distribution. The ensemble model outperformed or performed as good as the best individual model in all potential species distributions, while for ten species it performed worse than the best individual model in modeling realized distributions. The framework shows how combining continuous and consistent EO time series data with state of the art ML can be used to derive dynamic distribution maps. The produced time-series occurrence predictions can be used to quantify temporal trends and detect potential forest degradation.

Zootaxa ◽  
2022 ◽  
Vol 5089 (1) ◽  
pp. 1-66

A review of the Mesoamerican genus Paraphlebia Selys in Hagen, 1861 is presented, including diagnoses, illustrations of diagnostic characters, and distribution maps for all species. A key to the known males and females is provided. Eleven new species are described: P. akan Ortega-Salas & González-Soriano. sp. nov., P. chaak Ortega-Salas & González-Soriano sp. nov., P. chiarae Ortega-Salas sp. nov., P. esperanza Ortega-Salas & González-Soriano sp. nov., P. flinti Ortega-Salas & González-Soriano sp. nov., P. hunnal Ortega-Salas & González-Soriano sp. nov., P. itzamna Ortega-Salas, Jocque & González-Soriano sp. nov., P. ixchel Ortega-Salas & González-Soriano sp. nov., P. kauil Ortega-Salas & González-Soriano sp. nov., P. kinich Ortega-Salas & González-Soriano sp. nov., and P. kukulkan Jocque & Ortega-Salas sp. nov.  

2022 ◽  
Vol 66 (6) ◽  
pp. 434-441
T. S. Trifonova ◽  
A. V. Moiseenko ◽  
M. V. Bourkaltseva ◽  
O. V. Shaburova ◽  
A. K. Shaytan ◽  

Introduction. Giant phiKZ-like bacteriophages have a unique protein formation inside the capsid, an inner body (IB) with supercoiled DNA molecule wrapped around it. Standard cryo-electron microscopy (cryo-EM) approaches do not allow to distinguish this structure from the surrounding nucleic acid of the phage. We previously developed an analytical approach to visualize protein-DNA complexes on Escherichia coli bacterial cell slices using the chemical element phosphorus as a marker. In the study presented, we adapted this technique for much smaller objects, namely the capsids of phiKZ-like bacteriophages.Material and methods. Following electron microscopy techniques were used in the study: analytical (AEM) (electron energy loss spectroscopy, EELS), and cryo-EM (images of samples subjected to low and high dose of electron irradiation were compared).Results. We studied DNA packaging inside the capsids of giant bacteriophages phiEL from the Myoviridae family that infect Pseudomonas aeruginosa. Phosphorus distribution maps were obtained, showing an asymmetrical arrangement of DNA inside the capsid.Discussion. We developed and applied an IB imaging technique using a high angle dark-field detector (HAADF) and the STEM-EELS analytical approach. Phosphorus mapping by EELS and cryo-electron microscopy revealed a protein formation as IB within the phage phiEL capsid. The size of IB was estimated using theoretical calculations.Conclusion. The developed technique can be applied to study the distribution of phosphorus in other DNA- or RNA-containing viruses at relatively low concentrations of the element sought.

Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 98
Randa Osman ◽  
Yehia H. Dawood ◽  
Ahmed Melegy ◽  
Mohamed S. El-Bady ◽  
Ahmed Saleh ◽  

Due to heightening concern about radiation hazards protection, activity concentrations of 226Ra, 232Th, 40K in forty soil samples collected from Shoubra El Kheima in the South Nile Delta were measured using gamma-ray spectrometry. The mean activity concentrations of 226Ra and 40K were higher in 20% of the considered samples than the world average values. A comprehensive comparison with up-to-date data was carried out. Spatial distribution maps of the measured radionuclides and radiological parameters were generated. The distributions of natural radionuclides were influenced by the soil organic matter, clay content, and scavenger metals oxides, as well as differences in the physical and chemical attributes and solubility of these radionuclides. The results revealed that industrial activity and agricultural practices in the study area caused an incremental increase in 226Ra and 40K activity concentrations. It can be deduced that although there are intensive industrial activities in this area, the natural radiation that comes from the soil is normal and does not pose a significant radiological hazard to the public. The natural radioactivity of soil in this area needs to be monitored periodically to prevent unnecessary radiation exposure to inhabitants.

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 476
Pedro P. Socorro-Perdomo ◽  
Néstor R. Florido-Suárez ◽  
Julia C. Mirza-Rosca ◽  
Mircea Vicentiu Saceleanu

The increased popularity of Ti and its alloys as important biomaterials is driven by their low modulus, greater biocompatibility, and better corrosion resistance in comparison to traditional biomaterials, such as stainless steel and Co–Cr alloys. Ti alloys are successfully used in severe stress situations, such as Ti–6Al–4V, but this alloy is related to long-term health problems and, in response, different Ti alloys composed of non-toxic and non-allergic elements such as Nb, Zr, Mo, and Ta have been developed for biomedical applications. In this context, binary alloys of titanium and tantalum have been developed and are predicted to be potential products for medical purposes. More than this, today, novel biocompatible alloys such as high entropy alloys with Ti and Ta are considered for biomedical applications and therefore it is necessary to clarify the influence of tantalum on the behavior of the alloy. In this study, various Ti–xTa alloys (with x = 5, 15, 25, and 30) were characterized using different techniques. High-resolution maps of the materials’ surfaces were generated by scanning tunneling microscopy (STM), and atom distribution maps were obtained by energy dispersive X-ray spectroscopy (EDS). A thorough output of chemical composition, and hence the crystallographic structure of the alloys, was identified by X-ray diffraction (XRD). Additionally, the electrochemical behavior of these Ti–Ta alloys was investigated by EIS in simulated body fluid at different potentials. The passive layer resistance increases with the potential due to the formation of the passive layer of TiO2 and Ta2O5 and then decreases due to the dissolution processes through the passive film. Within the Ti–xTa alloys, Ti–25Ta demonstrates excellent passive layer and corrosion resistance properties, so it seems to be a promising product for metallic medical devices.

2022 ◽  
Vol 16 (1) ◽  
pp. e0009952
Kamal Eddine Benallal ◽  
Rafik Garni ◽  
Zoubir Harrat ◽  
Petr Volf ◽  
Vít Dvorak

Background Phlebotomine sand flies (Diptera: Psychodidae) are important vectors of various human and animal pathogens such as Bartonella bacilliformis, Phlebovirus, and parasitic protozoa of the genus Leishmania, causative agent of leishmaniases that account among most significant vector-borne diseases. The Maghreb countries Mauritania, Morocco, Algeria, Tunisia, and Libya occupy a vast area of North Africa and belong to most affected regions by these diseases. Locally varying climatic and ecological conditions support diverse sand fly fauna that includes many proven or suspected vectors. The aim of this review is to summarize often fragmented information and to provide an updated list of sand fly species of the Maghreb region with illustration of species-specific morphological features and maps of their reported distribution. Materials and methods The literature search focused on scholar databases to review information on the sand fly species distribution and their role in the disease transmissions in Mauritania, Morocco, Algeria, Tunisia, and Libya, surveying sources from the period between 1900 and 2020. Reported distribution of each species was collated using Google Earth, and distribution maps were drawn using ArcGIS software. Morphological illustrations were compiled from various published sources. Results and conclusions In total, 32 species of the genera Phlebotomus (Ph.) and Sergentomyia (Se.) were reported in the Maghreb region (15 from Libya, 18 from Tunisia, 23 from Morocco, 24 from Algeria, and 9 from Mauritania). Phlebotomus mariae and Se. africana subsp. asiatica were recorded only in Morocco, Ph. mascitti, Se. hirtus, and Se. tiberiadis only in Algeria, whereas Ph. duboscqi, Se. dubia, Se. africana africana, Se. lesleyae, Se. magna, and Se. freetownensis were reported only from Mauritania. Our review has updated and summarized the geographic distribution of 26 species reported so far in Morocco, Algeria, Tunisia, and Libya, excluding Mauritania from a detailed analysis due to the unavailability of accurate distribution data. In addition, morphological differences important for species identification are summarized with particular attention to closely related species such as Ph. papatasi and Ph. bergeroti, Ph. chabaudi, and Ph. riouxi, and Se. christophersi and Se. clydei.

A. Rjosk ◽  
C. Neinhuis ◽  
M. Monizi ◽  
T. Lautenschläger

While some African Floras were continuously revised and several are now almost completed, the Flora of Angola’s ‘Conspectus Florae Angolensis’ still remains incomplete. This applies also for Droseraceae and the genus Drosera. Our study aims to provide an identification key for Drosera of Angola and the Democratic Republic of the Congo, including all morphological characters of the different Angolan and Congolese taxa. Loans from different herbaria were studied. A list of important morphological characters was combined with data obtained by observations and measurements. Beside the identification key, nine species descriptions with drawings of the main characteristics, distribution maps and SEM-pictures of pollen and seed morphology are provided. The possibility of hybridisation is discussed. Despite difficulties such as varying morphology or hybridisation in some species, the identification key enables researchers to identify specimens by morphological characters.

Melania Stan ◽  
Rodica Serafim

The paper deals with eleven species and subspecies of tiger beetles of Romania. The specimens preserved in the collections of “Grigore Antipa” National Museum of Natural History were revised. Distribution maps based on the examined material are presented for each species.

2021 ◽  
Vol 9 (6) ◽  
pp. 813-822
Serine OMRANIA ◽  
Mbark LAHMAR ◽  
Ahmed DOUAIK ◽  
Hamza IAAICH ◽  

M’nasra region is well known for increasing levels of heavy metal pollution in the environment, mainly due to waste discharge of Ouled Berjal, the irrational use of fertilizers, and the discharge of waste from several industries. The objective of this study was to access the seasonal variations in the groundwater and soil quality with respect to heavy metal pollution. Water samples from wells and samples from soil near them were taken during wet (January - March 2017) and dry (July 2017) seasons and concentrations of Cd, Cu, Cr, Mn, Ni, Pb, and Zn were determined using an Atomic Absorption Spectrophotometer (AAS). Contamination factor for each heavy metal and Nemerow pollution index was calculated. Results of the study revealed a decrease in pollution degree from wet to dry for soil and an increase in the case of groundwater. Cu had the lowest and Ni had the highest concentration in irrigation water whereas, for soil, Cd had the lowest and Zn had the highest concentration. During the wet season, all the concentrations of heavy metals decreased compared to the dry season, this can be explained by the dilution of these concentrations by precipitation water and therefore to lower absorption of these heavy metals in the water of irrigations and/or soil. Vertical transfer of pollutants from topsoil to groundwater was assessed using Hierarchical Cluster Analysis to identify associations between heavy metals and soil texture. In the case of Ni and Cr, the variables corresponding to the concentrations from soil and groundwater were part of the same cluster, in both seasons, the distribution maps of concentrations confirmed the pattern of transfer. This study can be considered as a baseline for the seasonal variation of heavy metal pollution of groundwater and soil. This study can be used not only for monitoring the study area but also as a tool for the implementation of environmental protection policies.

2021 ◽  
Vol 43 (4) ◽  
pp. 1-15
Bui Hong Quang ◽  
Tran Duc Binh ◽  
Do Van Hai ◽  
Le Ngoc Han ◽  
Duong Thi Hoang ◽  

This study aimed to assess the relationship between distribution, altitude and investigation lines of vascular plants in Bat Xat Nature Reserve, Lao Cai province. Based on the collected specimens added 273 species of vascular plants belonging to 48 genera, 18 families, bringing the total number the currently known species are 1245 species of vascular plants belonging to 649 genera, 174 families and under 6 divisions such as. Of these, and there are 211 endemic and rare species consists have been recorded and 22 rare species 17 endemic species and updated scientific name 14 species added checklist to the Nature Reserve. Topographic, vegetation and distribution maps, changes in diversity and a checklist of endemic and rare species are shown.

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