Search Results (32)

The SE Baltic area, the former Eastern Prussia, is renowned for complex natural history. Over the past millions of years, the area experienced major geological events and geomorphic landscape transformations, resulting in the present relief configuration. Past climates and environments gave rise to the specific life-forms that proliferated in the Paleozoic and Mesozoic–Early Cenozoic shallow sea/lacustrine basins, and the Late Cenozoic riverine and continental settings. During the Paleogene, forested sub-tropical lands and deltaic settings of coastal sea lagoons gave rise to the famed amber formations (Blue Ground) hosting inclusions of resin-sealed insect and other small invertebrates that offer an unprecedented look into the 35–34 million-year habitats. Ferruginous sandstones, formed in shallow waters incorporating remains of thermophilous fauna—bivalves and gastropods, bryozoans, and sea urchins, among others—lie above the amber-bearing deposits. Oligocene–Miocene continental (riverine, lacustrine, and palustrine) conditions relate to the “Brown Coal Formation”, embedding a variety of fossil plants. Finally, the Quaternary Period brought dramatic geo-environmental shifts, with cyclic interstadial sea transgressions and massive glacial erosion events delivering fossiliferous erratics with an array of primitive Paleozoic and later Mesozoic life-forms. Overall, the extraordinary paleontology of the SE Baltic area adds, within its geological context, to the European geoheritage and the world natural heritage. Full article

Although wetlands are key habitats for biodiversity conservation, they are also among the most threatened ecosystems in the world. They are mainly affected by human pressures and threats, even when they are included in protected areas. The Padule di Fucecchio area is one of the largest and most significant inland marshes in Italy. It is also a wetland of international importance, as defined by the Ramsar Convention. However, studies of the plant communities it contains are surprisingly scarce and out of date. To address this issue, a phytosociological survey of aquatic and marshy vegetation was conducted. This analysis provided an unparalleled census of the area’s current aquatic and marsh vegetation. Eight different plant community types were reported in the former category and twenty-six in the latter, many of which were previously unknown in this territory. One of these is entirely novel and is described here for the first time. However, a comparison with previous data revealed that significant changes to the vegetation structure have occurred in recent decades. The hydrophyte communities have almost completely disappeared and many of the most sensitive plants in the most sensitive marsh communities have become rarer or disappeared. They have mostly been replaced by more resilient native plants and invasive alien species. Full article

The Early Pleistocene continental deposits of the Tiberino Basin (Central Italy) host exceptionally preserved fossil charophyte assemblages that provide critical insights into palaeoenvironmental and palaeoclimatic dynamics during a key phase of the Mediterranean evolution. Integrated micropalaeontological and sedimentological investigations at three reference sections reveal distinct charophyte communities characterized by Chara cf. hispida (Hartman) Wood, 1962, Chara cf. vulgaris Linnaeus, 1753, Nitellopsis obtusa (Desvaux in Loiseleur) Groves, 1919, and Lychnothamnus barbatus (Meyen, 1827) von Leonhardi 1863, not reported until now. These assemblages reflect a mosaic of stable lacustrine, ephemeral swamp, and palustrine environments shaped by increasing climatic oscillations approaching the Early–Middle Pleistocene transition. Comparative data from Mediterranean basins, such as Laguna de Gallocanta, Lake Afourgagh, and Ilgin Palaeolake (Türkiye), highlight the role of charophytes as sensitive indicators of hydrological and climatic variability. This study strengthens the palaeolimnological and palaeoenvironmental significance of charophyte fossils and proposes new avenues for multidisciplinary research into Quaternary environmental evolution in Mediterranean continental basins. Full article

Studies of early syn-rift successions in the Duwi Basin have revealed repetitive lacustrine carbonate deposits exhibiting regressive sequences and early diagenetic processes. Two main informal stratigraphic units (Units 1 and 2), spanning the Late Oligocene to Early Miocene, have been identified in the area. Unit 1 primarily consists of lacustrine limestone and calcrete deposits that formed in a palustrine environment, whereas Unit 2 is composed of dolomites and cherts, which developed during times of lake evaporation and desiccation under arid climatic conditions. A wide variety of pedogenic features, including brecciation, nodulization, rhizocretions, fissuring, microkarsts, and circumgranular cracks, dominate the carbonate sequence, indicating deposition in a marginal lacustrine setting. Integrated petrographic, mineralogical, geochemical, and isotopic studies of carbonate facies reveal two distinct evolutionary stages in the Duwi Basin, with dolomitization and silicification characterizing the late stage. Their isotopic compositions show a wide range of δ¹³C and δ¹⁸O values, ranging from −9.00‰ to −7.98‰ and from −10.03‰ to −0.68‰, respectively. Dolomite beds exhibit more negative δ¹³C and δ¹⁸O values, whereas palustrine limestones display higher (less negative) values. The upward trend of δ¹⁸O enrichment in carbonates suggests that the lake became hydrologically closed. Trace element concentrations serve as potential markers for distinguishing carbonate facies, aiding with paleoenvironmental and diagenetic interpretations. Our findings indicate that the studied dolomites and cherts formed under both biogenic and abiogenic conditions in an evaporative, alkaline-saline lake system. Biogenic dolomite and silica likely resulted from microbial activity, whereas abiogenic formation was driven by physicochemical conditions, including decreasing pH values and the presence of smectite clays. Tectonics, local climate, and provenance played crucial roles in controlling the overall diagenetic patterns and evolutionary history of the lake basin system during the Late Oligocene to Early Miocene. Full article

The fossiliferous Dursunlu Lignite Quarry (DLQ) is highlighted prominently in the archeological and paleontological literature because of the study of Pleistocene fauna and lithic artifacts, being considered the oldest Paleolithic site in Türkiye. Although the fauna and flora assemblage from DLQ are reasonably well known, taxonomic studies devoted to some groups, such as ostracods, mollusks, reptiles, and amphibians, have never been carried out. Here, we describe, illustrate, and study the taxonomic composition and ecological implications of the unpublished material of said groups, together with the aquatic plants and fish, recovered from six samples taken from the palustrine and peat bog facies of the sedimentary sequence. In addition, the recovered charophytes and cyprinids refine our taxonomical knowledge of both aquatic plants and fish. Our results concur with previous paleoenvironmental inferences based on flora and fauna composition—with DLQ representing a very shallow eutrophic lake with a dense palustrine vegetation belt during the cold (glacial) stage of the late Early Pleistocene—as well as highlight the study of all available groups as pivotal for better understanding the paleolake biota. We further conclude that the wetland areas of Dursunlu and surrounding steppe areas appear to have been an excellent environment for sporadic settlement of hominins during the Early Pleistocene, given the availability of food resources and easy access to water. Full article

Wetlands are essential carbon sinks in the global ecosystem, absorbing CO₂ in their biomass and soils and mitigating global warming. Accurate aboveground biomass (AGB) and organic carbon (Corg) estimation are crucial for wetland carbon sink research. Remote sensing (RS) data effectively estimate and map AGB and Corg in wetlands using various techniques, but there is still room to improve the efficiency of machine learning (ML)-based approaches. This study examined how different sample data treatments and plot sizes impact a random forest model’s performance based on RS for AGB and Corg prediction. The model was trained with samples of emergent vegetation collected in a palustrine wetland in southern Brazil and spectral variables (single bands and vegetation indices—VIs) from medium- and high-resolution optical images from Sentinel-2 and PlanetScope, respectively. The treatments involved AGB and Corg values dimensioned for three different plot sizes (G1) and the same subjected to normalized natural logarithmic transformation—NL (G2). Therefore, six AGB and Corg models were created for each sensor. Models and sensor performance and spectral variable importance were compared. In our results, NL sample data RF models proved more accurate. Larger plots produced smaller prediction errors with S2 models, indicating the influence of plot size on the reliability of the estimate. S2 surpassed PS in AGB/Corg prediction, respectively—S2 (R² 0.87; 0.89, RMSE OOB: between 19.7% and 22.7%); PS (R² 0.86; 0.86, RMSE OOB: between 21% and 35.9%)—but PS was superior in mapping spatial variability. The VI CO₂Flux and S2’s SWIR, blue, green, and RE bands 6 and 7 were more important for AGB/Corg prediction. The contribution of this study is the finding that in addition to optimizing RF model parameters, optimizing the AGB and Corg dataset collected in the field, i.e., evaluating normalization and plot sizes, is crucial to obtain more accurate estimates with RS- and ML-based models. This approach enhances AGB/Corg stock estimation in wetlands, and the highlighted predictors can act as spectral indicators of these ecological functions. These results have the potential to guide standardization in the collection and processing of input data for predictive models of AGB/Corg in wetlands, with the aim of ensuring consistent predictions in inventories and monitoring. Full article

New ornithopod remains have recently been discovered at the Vadillos-1 paleontological site, in Cuenca Province, Central Spain. These remains were collected in sandy and clayey deposits within “Wealden” alluvial facies, which correspond to an upper Barremian (Lower Cretaceous) alluvial-palustrine muddy floodplain paleoenvironment. The remains correspond to a part of a sacrum, including three fused sacral vertebral centra with sacral ribs and part of the sacral yoke, together with an isolated unfused sacral vertebra. An incomplete ischium has also been identified, likely belonging to the same individual. The sacral block exhibits a broad sulcus that begins at the most anterior sacral vertebra, continues through the middle vertebra, and ends in the area where the middle and the most posterior vertebrae are fused. The non fused sacral vertebra also displays a ventral sulcus. The incomplete ischium has a curved shaft with a triangular cross section towards the distal end. The combination of the morphological features of the sacrum and ischium allow its attribution to Iguanodon cf. bernissartensis. This species is identified in the area for the first time, adding new valuable data about the dinosaur assemblages from the Lower Cretaceous of Spain. Full article

Wetlands are among the world’s valuable ecosystems for biodiversity conservation, but they are also among the most threatened habitats, heavily impacted by human pressures and threats. The Mediterranean basin features numerous small lakes, ponds, and pools, whose number and quality are decreasing at an alarming rate, and whose biodiversity is often little or not at all known. As a better knowledge of the biotic components of these minor water bodies is necessary, with this aim a phytosociological survey campaign was carried out in southern Tuscany (central Italy), an area where little information is available on the vegetation of aquatic and palustrine biotopes. Numerous previously unknown water bodies were located and surveyed in this work, while others already known were resurveyed. These investigations allowed us to identify 28 plant communities which can be classified into seven syntaxonomic classes. A new subassociation (Ranunculo ophioglossifolii-Callitrichetum stagnalis subass. ranunculetosum peltati) is described. The identification of the site-associated Natura2000 habitats led to the recognition of five habitats of conservation interest at the national and European level. The results of these investigations will improve the knowledge of the flora and vegetation of these small but valuable natural areas, providing a basis for their conservation. Full article

Accurate assessments of greenhouse gas emissions and carbon sequestration in natural ecosystems are necessary to develop climate mitigation strategies. Regional and national-level assessments of carbon sequestration require high-resolution data to be available for large areas, increasing the need for remote sensing products that quantify carbon stocks and fluxes. The Intergovernmental Panel on Climate Change (IPCC) provides guidelines on how to quantify carbon flux using land cover land change and biomass carbon stock information. Net primary productivity (NPP), carbon uptake, and storage in vegetation, can also be used to model net carbon sequestration and net carbon export from an ecosystem (net ecosystem carbon balance). While biomass and NPP map products for terrestrial ecosystems are available, there are currently no conterminous United States (CONUS) biomass carbon stock or NPP maps for tidal herbaceous marshes. In this study, we used peak soil adjusted vegetation index (SAVI) values, derived from Landsat 8 composites, and five other vegetation indices, plus a categorical variable for the CONUS region (Pacific Northwest, California, Northeast, Mid-Atlantic, South Atlantic-Gulf, or Everglades), to model spatially explicit aboveground peak biomass stocks in tidal marshes (i.e., tidal palustrine and estuarine herbaceous marshes) for the first time. Tidal marsh carbon conversion factors, root-to-shoot ratios, and vegetation turnover rates, were compiled from the literature and used to convert peak aboveground biomass to peak total (above- and belowground) biomass and NPP. An extensive literature search for aboveground turnover rates produced sparse and variable values; therefore, we used an informed assumption of a turnover rate of one crop per year for all CONUS tidal marshes. Due to the lack of turnover rate data, the NPP map is identical to the peak biomass carbon stock map. In reality, it is probable that turnover rate varies by region, given seasonal length differences; however, the NPP map provides the best available information on spatially explicit CONUS tidal marsh NPP. This study identifies gaps in the scientific knowledge, to support future studies in addressing this lack of turnover data. Across CONUS, average total peak biomass carbon stock in tidal marshes was 848 g C m⁻² (871 g C m⁻² in palustrine and 838 g C m⁻² in estuarine marshes), and based on a median biomass turnover rate of 1, it is expected that the mean NPP annual flux for tidal marshes is similar (e.g., 848 g C m⁻² y⁻¹). Peak biomass carbon stocks in tidal marshes were lowest in the Florida Everglades region and highest in the California regions. These are the first fine-scale national maps of biomass carbon and NPP for tidal wetlands, spanning all of CONUS. These estimates of CONUS total peak biomass carbon stocks and NPP rates for tidal marshes can support regional- and national-scale assessments of greenhouse gas emissions, as well as natural resource management of coastal wetlands, as part of nature-based climate solution efforts. Full article

Biodiversity conservation decisions are typically based on limited data and resources. For this reason, there is great interest in surveying taxa that may allow for a rapid assessment of the biodiversity at a site. Numerous taxa have been proposed and utilized for rapid assessments that allow for such a survey in a matter of weeks or less. Herein, we test the idea that nocturnal moths have many of the characteristics that make them ideal for such surveys, such as relative ease of identification, strong ecological association with specific plant species and habitats, high alpha diversity, extended seasonal activity, and ease of trapping. We demonstrate that even in a few hours of sampling during single night surveys, moth communities are predictive of regional forest types at sampling sites in New Jersey. We sampled moths in five different forest habitats in New Jersey, USA: Pine Barrens, Upland Deciduous Forest, Palustrine Deciduous Forest, Maritime Forest, and Ruderal/Disturbed Forests, at four sites per forest type. Non-metric multidimensional scaling (NMDS) analyses revealed that moth communities differ significantly across these four forest types (p < 0.01). We used Analysis of Similarity (ANOSIM) R tests to quantify the degree of differentiation among moth communities, and found that Tortricidae (R = 0.657) and Geometridae (R = 0.637) predict forest communities nearly as well as the total moth diversity (R = 0.668). Uncommon species (R = 0.665) were better predictors than common species (R = 0.500). Host plant generalists (R = 0.654) were better predictors than specialists (0.538), which was a surprising find. Full article

The most prominent horsetail species, Equisetum arvense, has an array of different medicinal properties, thus the proper authentication and differentiation of the plant from the more toxic Equisetum palustre is important. This study sought to identify different samples of E. arvense and E. palustre using three analytical methods. The first method involved the use of HPTLC analysis, as proposed by the European Pharmacopoeia. The second, HPLC-ESI-MS/MS, is capable of both identification and quantification and was used to determine the Equisetum alkaloid content in each sample. A third method was DNA barcoding, which identifies the samples based on their genetic make-up. Both HPTLC and HPLC-ESI-MS/MS proved to be suitable methods of identification, with HPLC-ESI-MS/MS proving the more sophisticated method for the quantification of alkaloids in the Equisetum samples and for determining the adulteration of E. arvense. For DNA barcoding, optimal primer pairs were elucidated to allow for the combined use of the rbcL and ITS markers to accurately identify each species. As new DNA marker sequences were added to GenBank, the reference library has been enriched for future work with these horsetail species. Full article

Wetlands play a critical role in maintaining stable and productive ecosystems, and they continue to be at heightened risk from anthropogenic and natural degradation, especially along the rapidly developing Atlantic Coastal Plain of North America. As such, strategies to develop up-to-date and high-resolution wetland inventories and classifications remain highly relevant in the context of accelerating sea-level rise and coastal changes. Historically, satellite and airborne remote sensing data along with traditional field-based methods have been used for wetland delineation, yet, more recently, the advent of Uncrewed Aerial Systems (UAS) platforms and sensors is opening new avenues of performing rapid and accurate wetland classifications. To test the relative advantages and limitations of UAS technologies for wetland mapping and classification, we developed wetland classification models using UAS-collected multispectral and UAS-collected light detection and ranging (LiDAR) data relative to airborne-derived LiDAR models of wetland types ranging from palustrine to estuarine. The models were parameterized through a pixel-based random forest algorithm to evaluate model performance systematically and establish variable importance for a suite of variables including topographic, hydrologic, and vegetation-based indices. Based on our experimental results, the average overall classification accuracy and kappa coefficients for the UAS LiDAR-derived models are 75.29% and 0.74, respectively, compared to 79.80% and 0.75 for the airborne LiDAR-derived models, with significant differences in the spatial representation of final wetland classes. The resulting classification maps for the UAS models capture more precise wetland delineations than those of airborne models when trained with ground reference data collected at the same time as the UAS flights. The similar accuracy between the airborne and UAS models suggest that the UAS LiDAR is comparable to the airborne LiDAR. However, given poor revisit time of the airborne surveys and the high spatial resolution and precision of the UAS data, UAS-collected LiDAR provides excellent complementary data to statewide airborne missions or for specific applications that require hyperspatial data. For more structurally complex wetland types (such as the palustrine scrub shrub), UAS hyperspatial LiDAR data performs better and is much more advantageous to use in delineation and classification models. The results of this study contribute towards enhancing wetland delineation and classification models using data collected from multiple UAS platforms. Full article

The terrestrial Lower Cretaceous Cedar Mountain Formation, Utah, is a critical archive of paleoclimate, tectonics, and vertebrate ecology and evolution. Early Cretaceous carbon cycle perturbations associated with ocean anoxia have been interpreted from this succession, as expressed in stable carbon isotopes. However, refining the timing of the observed stable isotope excursions remains a key challenge in understanding how marine anoxia affects the Earth system, and is ultimately recorded in the terrestrial realm. The geochronology and geochemistry of a terrestrial carbonate near the base of this succession, which potentially records the Ap7 global carbon isotope excursion, is studied here. Petrographic and geochemical analyses are used to test plausible mechanisms for U incorporation into the calcite lattice in this sample. Using these methods, the hypothesis that the incorporation of U was at or close to the timing of carbonate precipitation is evaluated. U–Pb geochronology of calcite indicates a plausible Early Cretaceous age. However, comparison of the new U–Pb ages of calcite with detrital zircon maximum depositional ages immediately beneath the studied sample indicates a disparity in the apparent sedimentation rates if both types of geochronologic information are interpreted as reflecting the timing of sediment deposition. The totality of data supports an early, and high-temperature, diagenetic timing of U incorporation, with potential for minor leaching of U in subsequent fluid–rock interaction. The most likely mechanism for U transport and immobilization in these samples is hydrothermal fluid–rock interaction. Therefore, the radiometric ages, and corresponding stable isotope composition of U-bearing carbonate domains in this sample, indicate early subsurface fluid–rock interactions and not a record of atmosphere–soil geochemical reactions. Full article

Lithofacies belonging to mud-flat and palustrine deposits (lake margin) in the Miocene of the Madrid Basin (Spain) have been studied. Four lithofacies corresponding to mud flat (1 and 3) and palustrine (2 and 4) deposits have been differentiated. Units 1 and 3 consist mainly of mudstones and carbonates (calcretes and diolocretes). The clay fraction is dominated by trioctahedral smectite (up to 79%) with illite and kaolinite as minor components. The d(060) spacing value shows reflections at 1.52 and 1.50 Å indicating also the presence of dioctahedral phyllosilicates. Unit 2 consists predominantly of lutites (claystones), locally with carbonate and chert nodules. The clay fraction is dominated by sepiolite (up to 96%) with variable contents of smectite and subordinate illite. The d(060) spacing value shows reflections at 1.51 and 1.52 Å indicating trioctahedral clay minerals. Unit 4 consists mostly of carbonates (limestones) with mudstone and lutite inserts. The clay fraction shows different contents of sepiolite, palygorskite and dioctahedral smectite. The analysis of a selection of trace elements (Cr, Co, Th, La, Sc) has allowed us to determine the characteristics of the source area as dioritic, somewhat different from those of the nearby materials from the Batallones sector. Sepiolite shows FWHM values ranging between 0.68 and 1.10 (2θ), indicating “low crystallinity sepiolite”. Differences in the conditions of formation of magnesian smectite and palygorskite have been observed in the mud-flat and palustrine deposits. The formation of sepiolite mainly by neoformation in palustrine deposits with different hydrochemistry is remarkable, leading to differences in fibre size and crystallinity of the fibrous clay mineral. Authigenic transformation processes from previous Al-rich phases would be responsible for the formation of saponite and palygorskite in mud flat and palustrine environments, with different pH conditions. Full article

Antimicrobial peptides (AMPs) are considered as promising antimicrobial agents due to their potent bioactivity. Palustrin-2 peptides were previously found to exhibit broad-spectrum antimicrobial activity with low haemolytic activity. Therefore, GL-29 was used as a template for further modification and study. Firstly, the truncated analogue, GL-22, was designed to examine the function of the ‘Rana box’, which was confirmed to have no impact on antimicrobial activity. The results of antimicrobial activity assessment against seven microorganisms demonstrated GL-22 to have a broad-spectrum antimicrobial activity, but weak potency against Candida albicans (C. albicans). These data were similar to those of GL-29, but GL-22 showed much lower haemolysis and lower cytotoxicity against HaCaT cells. Moreover, GL-22 exhibited potent in vivo activity at 4 × MIC against Staphylococcus aureus (S. aureus)-infected larvae. Several short analogues, from the C-terminus and N-terminus of GL-22, were modified to identify the shortest functional motif. However, the results demonstrated that the shorter peptides did not exhibit potent antimicrobial activity, and the factors that affect the bioactive potency of these short analogues need to be further studied. Full article