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The finding of Panstrongylus geniculatus nymphs inside a house in northeastern Antioquia, Colombia, and the reports related to their increasing presence in homes suggest the need for surveillance methods for monitoring the invasion processes. We analyzed the morphological differences between a wild population and its laboratory descendants, using the techniques of geometric morphometry, with the idea that such differences might parallel those between sylvatic and synanthropic populations. The analyses over five generations showed differences in size but not in shape. Head size and wing size were both reduced from sylvatic to laboratory populations, but the decrease in head size occurred only up to the second generation while the decrease in wing size proceeded up to the fifth generation. In contrast, although a decrease in sexual size dimorphism has been proposed as a marker of colonization in human dwellings, we did not detect any significant loss of dimorphism between sexes of P. geniculatus over the five generations studied. We conclude that size changes may have a physiological origin in response to a change of ecotopes, but more than five generations may be required for the expression of permanent morphological markers of human dwellings colonization.

We analyzed the chemical compositions of dust and sea‐salt particles in the EPICA Dome C (EDC) ice core during 26–7 kyr BP using an ice‐sublimation technique and compared the results with existing data of the Dome Fuji (DF) ice core. Combined with ion concentration data, our data suggested similar sea‐salt fluxes in both cores and significantly lower dust flux in the EDC core. The differences in modal size and aspect ratio of dust particles between the two cores support the dominance of Patagonian source suggested by earlier works. The compositions of calcic dust showed major change at ~17 kyr BP, possibly reflecting a relative increase in dust transported via the upper troposphere. The calcium sulfate fraction was higher in the DF core than in the EDC core after ~17 kyr BP, suggesting that higher Patagonian dust contribution to the DF region. Abundant NaCl particles were found in the DF core in comparison with the EDC core from the LGM to early Holocene, possibly because of the high concentration of terrestrial dust in the DF core that reduced acid availability for sea‐salt modification. During the Holocene, the lower NaCl fraction and Cl−/Na+ ratio in the EDC core suggested that most Cl− was lost to the atmosphere from snow at Dome C, while it was preserved at Dome Fuji as NaCl and solid solution. Key Points: Dust flux in the Dome C core is significantly lower than in the Dome Fuji core from the LGM to the early HoloceneComparison of dust size and aspect ratio between the two cores suggest dominance of Patagonian dust source during the LGMMost Cl was lost to the atmosphere from snow at Dome C, while it was preserved at Dome Fuji as NaCl and in solid solution in the Holocene [ABSTRACT FROM AUTHOR]

Investigation of organic compounds in ice cores can potentially unlock a wealth of new information in these climate archives. We present results from the first ever ice core drilled on sub‐Antarctic island Bouvet, representing a climatologically important but understudied region. We analyze a suite of novel and more familiar organic compounds in the ice core, alongside commonly measured ions. Methanesulfonic acid shows a significant, positive correlation to winter sea ice concentration, as does a fatty acid compound, oleic acid. Both may be sourced from spring phytoplankton blooms, which are larger following greater sea ice extent in the preceding winter. Oxalate, formate, and acetate are positively correlated to sea ice concentration in summer, but sources of these require further investigation. This study demonstrates the potential application of organic compounds from the marine biosphere in generating multiproxy sea ice records, which is critical in improving our understanding of past sea ice changes. Plain Language Summary: Ice cores are vertical cylinders of ice drilled from an ice sheet, younger at the top and older at the bottom. Particles emitted from plants and animals on land and in the ocean, containing organic chemical compounds, are carried by atmospheric circulation, deposited on the ice surface, and become trapped inside ice layers. They are a record of environmental conditions at the location and time the particles originally formed. Here, we look for a number of these organic compounds in an ice core from Bouvet Island in the sub‐Antarctic. We find the amounts of some are related to amounts of sea ice around the island in the spring. This is because the particles are originally emitted by phytoplankton, for which the amount of sea ice that year controls the amount of phytoplankton (more sea ice in the winter = greater area of sea ice break up in spring = more phytoplankton in spring). We find other organic compounds are related to amounts of sea ice in summer, but their sources are less well known. Combining these records with their relationships to sea ice will be useful in helping us to better understand sea ice changes in the past. Key Points: We analyzed a suite of organic compounds,alongside commonly measured ions, in the first ever shallow ice core from Bouvet IslandMultiple marine‐sourced organic compounds are detected throughout the coreOrganic compounds, alongside MSA, show significant positive correlations with sea ice [ABSTRACT FROM AUTHOR]

The Walloon region of Belgium has launched a research project that aims at elaborating a methodology for automated, high-quality land cover mapping, based primarily on its yearly 0.25m orthophoto coverage. Whereas in urban areas an object-based (OBIA) approach has been the privileged path in the last years as it allows taking into account shape information relevant for the characterization of man-made constructions, such an approach has its limits in the rural and more natural areas due to increased difficulties for segmentation and less sharp boundaries, thus calling for a pixel-based approach. The project thus consists in developing a combination of methods, and to integrate their results through an ensemble fusion approach. As many of the more natural land cover classes have temporal profiles which cannot be detected in a one-date orthoimage, Sentinel 1 and 2 data are also included in order to take advantage of their higher spectral and temporal resolution. All methods are trained using existing regional databases. In a second step, we combine the different LC classification results by fusioning them into one high-accuracy (over 90% OA) product, using a series of different approaches ranging from rule-based to machine learning to the Dempster-Shafer method. The entire toolchain is based on free and open source software, mainly GRASS GIS and Orfeo ToolBox. Results indicate the importance of the quality of the individual classifications for the fusion results and justify the choice of combining OBIA and pixel-based approaches in order to avoid the pitfalls of each. [ABSTRACT FROM AUTHOR]