Goulandris Natural History Museum

For the study of the aqueous history of Mars, the knowledge of mineral characteristics for specific geologic environments is essential [1]. Previous studies of regions on Earth suitable as analogs for studying geological processes on planetary surfaces, such as the Italian island Vulcano [2] already enabled the identification of secondary sulfate minerals formed by acid alteration of volcanic deposits due to fumarolic activity. In this work, we extend this study with the spectral investigation of alteration minerals measured on the volcanic island Milos (Greece) during fieldwork performed in 2024.Milos is a volcanic island in the Aegean Sea and a part of the subduction-related South Aegean Volcanic Arc [3]. Hydrothermal activity changed the initial composition of the rocks and led to the formation of various secondary minerals - making the island an ideal location to extend our spectral library, coupled with geologic context information. Spectral measurements presented here were performed with a portable VIS-NIR spectrometer operating at wavelengths between 0.35 and 2.5 µm in two locations on the island: 1) a persistently active fumarolic field in the area of Kalamos Dome (Fig. 1 a + b) and 2) an abandoned sulfur mine at Paliorema (Fig. 1 c + d), where sulfur was mainly extracted from underground deposits.Both locations reveal a variety of alteration minerals, in particular sulfates next to native sulfur. Similar to what could be identified on Vulcano, alteration minerals on Milos are dominated by Fe- and Al-bearing sulfates (Fig. 2). However, whereas sulfate minerals such as jarosite (KFe33+[(OH)6(SO4)2]) and alunite (KAl3[(OH)6(SO4)2]) are dominant on Vulcano, different hydrous phases, such as copiapite (Fe2+Fe3+4[(OH)2(SO4)6] x 20H2O) and alunogene (Al2[SO4]3 x 17H2O), are prominent in the area of the Kalamos. This also accounts for hydrated silica, the typical alteration residue. In contrast to Vulcano, where silica occur as amorphous silica gel [4], silica on Milos have a higher water content and crystallinity, mainly identified as chert and chalcedony (Fig. 2). The fossilized hydrothermal system at Paliorema displays more mineralogical diversity. There we have identified jarosite and alunite and also alunogene and copiapite (Fig. 2). Additionally, we see spectral evidence for secondary mineral phases such as melanterite (Fe2+SO4 x 7H2O) and the rare secondary minerals amarantite Fe23+[O(SO4)2] x 7H2O).The identified minerals are known to occur in the vicinity of fumaroles and are expected to result from the direct interaction between the surface material of the volcanic rocks and fumarolic gases [4]. Secondary minerals form through leaching of the volcanic rock surface, leaving silica behind. Some minerals can also directly precipitate from volcanic gases. The diversity of hydrous minerals compared to what could be observed on Vulcano [2] implies more complex aqueous settings in the formation environments and possible dehydration patterns. The study of altered volcanic deposits on Milos, with its diverse mineralogical assemblages, provides valuable analogs for understanding similar processes on Mars.Fig. 1: a) Kalamos Dome with b) differently colored hydrothermally altered volcanic deposits and c - d) the sulfur mine in Paliorema. See Fig. 2 for spectra taken at the locations indicated by green letters. Fig. 2: VIS/NIR spectra acquired in areas of hydrothermal and acid alteration of volcanic deposits on a) the Greek island Milos and b) – d) the Italian island Vulcano [2]. For instance, the detection of sulfates, hydrated silica, and other secondary minerals on Milos mirrors mineralogical findings from Martian regions like Gale Crater and Meridiani Planum [5]. These parallels suggest that fumarolic and hydrothermal systems on Mars may have fostered similar alteration processes, offering clues about the planet's past habitability. The ongoing work also involves detailed laboratory analyses of Milos samples using VIS-NIR, LIBS, and Raman spectroscopy to expand the mineralogical inventory and to deepen the understanding of hydrothermal alteration processes and their implications for Martian geology and habitability.

In recent years, the need to protect and conserve biodiversity has become more critical than ever before, as a prerequisite for both sustainable development and the very survival of the human species. This has made it a priority for the scientific community to develop technological solutions that provide data and information for monitoring, directly or indirectly, biodiversity and the drivers of change. A new era of satellite earth observation upgrades the potential of Remote Sensing (RS) to support, at relatively low cost, but with high accuracy the extraction of information over large areas, at regular intervals, and over extended periods of time. Also, the recent development of the Earth Observation Data Cubes (EODC) framework facilitates EO data management and information extraction, enabling the mapping and monitoring of temporal and spatial patterns on the Earth’s surface. This submission presents the ELBIOS EODC, specifically developed to support the biodiversity management and conservation over Greece. Based on the Open Data Cube (ODC) framework, it exploits multi-spectral optical Copernicus Sentinel-2 data and provides a series of Satellite Earth Observation (SEO) biodiversity products and spectral indices nationwide.

Eupholidoptera kekropssp. nov. belonging to the E. prasina group, is described from mainland Greece. The new species is the first known member of this group from mainland Greece and mainland Europe. Differentiating morphological characteristics, mainly of the subgenital plate and titilator, are presented.

The metabolite profiling of saffron (Crocus sativus L.) from several countries was measured by using ultra-performance liquid chromatography combined with high resolution mass spectrometry (UPLC-HR MS). Multivariate statistical analysis was employed to distinguish among the several samples of C. sativus L. from Greece, Italy, Morocco, Iran, India, Afghanistan and Kashmir. The results of this study showed that the phytochemical content in the samples of C. sativus L. were obviously diverse in the different countries of origin. The metabolomics approach was deemed to be the most suitable in order to evaluate the enormous array of putative metabolites among the saffron samples studied, and was able to provide a comparative phytochemical screening of these samples. Several markers have been identified that aided the differentiation of a group from its counterparts. This can be important for the selection of the appropriate saffron sample, in view of its health-promoting effect which occurs through the modulation of various biological and physiological processes.

A new multimetric index (HeLLBI) based on littoral benthic macroinvertebrates is presented in this paper for classification of Greek natural lakes, in compliance with the requirements of Water Framework Directive (WFD). The method was developed based on the collection of littoral benthic invertebrate fauna and environmental data from 109 sampling sites in 21 natural lakes of the Greek National Water Monitoring Network. We focused the analysis on the effects of shore morphological alterations and eutrophication to the littoral invertebrate fauna, identified to family level, except oligochaetes, which were identified as a class, and more particularly to taxonomic composition and abundance, to taxa sensitivity, and to richness/diversity. Three metrics were included in the multimeric index: the relative abundance of Odonata classes, the Average Score per Taxon, and the Simpson’s diversity index. The metrics were converted to ecological quality ratios and ecological class boundaries were defined. The final multimetric index HeLLBI is expressed as an arithmetic average of normalized ecological quality ratios of the above metrics and a final score was assigned to each lake. Pressure-response relationships of HeLLBI scores were statistically tested for morphological alterations, expressed as percentage of artificial shoreline, and eutrophication, expressed as total phosphorus. The HeLLBI scores correspond to ecological classes, according to WFD, and sampling sites with different ecological status contained distinct biological communities; those at high status where more diverse and with sensitive taxa and as the water quality deteriorated, macroinvertebrate assemblages consisted of fewer and more tolerant to degradation taxa. The HeLLBI method gave a reliable assessment of littoral benthic invertebrate fauna of Greek natural lakes and could be a useful tool for the classification of ecological status of other Mediterranean lakes.

A classic method for assessing the reference crop evapotranspiration (ETo) is the pan evaporation (Epan) method that uses Epan measurements and pan coefficient (kp) models, which can be functions of relative humidity (RH), wind speed (u2), and temperature (T). The aim of this study is to present a methodology for evaluating the robustness of regression coefficients associated to climate parameters (RH, u2, and T) in pan method models during recalibration at local conditions. Two years of daily data from April to October (warm season) of meteorological parameters, Epan measurements from class A pan evaporimeter and ETo estimated by ASCE-standardized method for the climatic conditions of Thessaloniki (Greece, semi-arid environment), were used. The regression coefficients of six general nonlinear (NLR) regression Epan models were analyzed through recalibration using a technique called “random cross-validation nonlinear regression RCV-NLR” that produced 1000 random splits of the initial dataset into calibration and validation sets using a constant proportion (70% and 30%, respectively). The variance of the regression coefficients was analyzed based on the 95% interval of the highest posterior density distribution. NLR models that included coefficients with a 95% HPD interval that fluctuates in both positive and negative values were considered nonrobust. The machine-learning technique of random forests (RF) was also used to build a RF model that includes Epan, u2, RH, and T parameters. This model was used as a benchmark for evaluating the predictive accuracy of NLR models but, also, for assessing the relative importance of the predictor climate variables if they were all included in one NLR model. The findings of this study indicated that locally calibrated NLR functions that use only the Epan parameter presented better results, while the inclusion of additional climate parameters was redundant and led to underfitting.

Spatial crop nitrogen (N) management has advanced over the years by using canopy reflectance data to make N recommendations. But the value of an automated system for variable-rate applications (VRA) has not been extensively demonstrated in cotton. This study evaluated the performance of an integrated system for on-the-go VRA at a 1-m spatial resolution in two different field trials in 2016 and 2017. The VRA system applied consistently less fertilizer N than the farmer practice, 42% and 33% less total N in the 2016 and 2017 field trials, respectively. Despite the reduced N inputs, increased energy-use efficiency (EUE) by 16% and return to N cost by €81/ha in 2016, VRA still over-applied N because of lack of yield response to N fertilizer. In the 2017 field, VRA yield gains by 5–8% over the farmer practice were not statistically significant and came about after cotton regrowth due to a bollworm infestation. With or without a back-off function in effect, VRA delivered an Economic Optimum N Rate, greatly increased N recovery by 12–22%, EUE by 26% and net return to N by €190–248/ha in comparison to the farmer. The reduction of N inputs also improved coupling of the soil-crop N cycle by reducing the effects of excess farmer application on soil acidity, electrical conductivity and residual nitrates in the root zone. Under the field conditions of this study, implementation of the high-resolution VRA can result in environmental and economic benefits especially in non-problematic fields where the crop responds to N fertilization.

The Egyptian weasel (Mustela subpalmata) is a small mustelid with a distribution restricted to the lower Nile Valley and the Nile Delta. Traditionally considered a subspecies of the least weasel (M. nivalis), it is currently recognized as a separate species based on morphology. Here we present the first genetic assessment of the taxonomic status of the Egyptian weasel by comparing mitochondrial DNA (Cytochrome b gene and control region) sequences to those of least weasels from the western Palearctic, with a focus on the Mediterranean region. Our results provide no evidence to support the view that the Egyptian weasel is genetically distinct from the least weasel, as we found that, for both Cytochrome b and control region, haplotypes were shared between the two taxa. Specifically, the Cytochrome b and control region haplotypes detected in the Egyptian weasel were also present in M. nivalis from Turkey and Malta, two populations genetically analysed here for the first time. Our results suggest that the Egyptian weasel is distinct from the least weasel populations currently living in the Maghreb, which were inferred to be the result of an earlier colonization of North Africa, but the genetic data alone do not allow us to determine whether the Egyptian weasel is native or introduced. Nevertheless, the observed genetic patterns, together with the weasel fossil record in Israel and the unique commensal lifestyle of the Egyptian weasel, are consistent with the hypothesis that the Egyptian population is a relict of past range expansion from the Levant into Egypt. We suggest that the large size and characteristic sexual dimorphism of the Egyptian weasel are likely to represent ecotypic variation, but genomic studies are required to clarify the extent of its functional genetic divergence.