Occurrence Of Springs Research Articles

Characterization and Genetic Diversity of Listeria monocytogenes Isolated from Cattle Abortions in Latvia, 2013-2018.

Listeria monocytogenes can cause disease in humans and in a wide range of animal species, especially in farm ruminants. The aim of the study was to determine the prevalence and genetic diversity of L. monocytogenes related to 1185 cattle abortion cases in Latvia during 2013–2018. The prevalence of L. monocytogenes among cattle abortions was 16.1% (191/1185). The seasonality of L. monocytogenes abortions was observed with significantly higher occurrence (p < 0.01) in spring (March–May). In 61.0% of the cases, the affected cattle were under four years of age. L. monocytogenes abortions were observed during the third (64.6%) and second (33.3%) trimesters of gestation. Overall, 27 different sequence types (ST) were detected, and four of them, ST29 (clonal complex, CC29), ST37 (CC37), ST451 (CC11) and ST7 (CC7), covered more than half of the L. monocytogenes isolates. Key virulence factors like the prfA-dependent virulence cluster and inlA, inlB were observed in all the analyzed isolates, but lntA, inlF, inlJ, vip were associated with individual sequence types. Our results confirmed that L. monocytogenes is the most important causative agent of cattle abortions in Latvia and more than 20 different STs were observed in L. monocytogenes abortions in cattle.

Groundwater resources in a fractured-rock aquifer, Conglomerate of Portofino

ABSTRACT Hydrogeological mapping is a key tool for groundwater resource management. Generally, hydrogeological maps focus mainly on porous or karst aquifer at large scale. In a fractured-rock aquifer, the groundwater flow path is not immediately deductible due to the intrinsic complexity of fracture systems. Then, it is of crucial importance collecting a complete dataset describing the site of interest: fault and strata patterns, geomorphological features, occurrence of springs. Here we present the hydrogeological map at 1:10,000 scale of the fractured rock aquifer of Conglomerate of Portofino (Italy). The graphical information contained in this map is based on the authors’ field survey and the revision of papers written for academic purposes and technical reports. The aim of the research is to achieve a useful tool for land planning, conservation of groundwater resource and geo-hydrological risk reduction in the unique area of the Natural Park of Portofino.

Natural Laboratories for the Study of CO2 Geological Storage in Romania

The study of natural laboratories for CO2 geological storage is still important as it can reveal important aspects related to environmental impacts of a potential CO2 leakage from an anthropic reservoir and can contribute to further understanding of CO2 migration pathways. Furthermore, natural laboratories are a good opportunity for testing innovative monitoring methods. Although not specified in any database of natural laboratories for the study of CO2 geological storage, Romania has many areas with natural CO2 emissions that can be used for this purpose. In the framework of a national project (financed by the Ministry of Education and Research), we have started to inventory, evaluate and make a selection of best candidate sites for further study in two zones, Banat (western part of Romania) and Harghita (eastern part of Romania). The two zones have different geological structures, and the origin of CO2 emissions in the two areas is related to the magmatic activity, the magmatism of the Eastern Carpathians in Harghita and the neogene magmatism of the Apuseni Mountains in Banat. The structural model of Banat is closely correlated with the strong tectonization of the sedimentary cover (with a maximum thickness of 5000 m). The overall picture is that of horsts and grabens. The tectonic blocks are separated by active, deep faults, confirmed by the occurrence of thermal and mineral water springs (Biled, Calacea, Timișoara, Buziaș, Pișchia, Lipova, Ivanda) and mofettes (Buziaș, Seceani), with releases of CO2, radon, helium, argon and other gases of crustal origin. Harghita zone is included in the mofettic aureola of the Eastern Carpathians. The deep geological structure of the zone is dominated by three fault systems comprising crustal, regional and local faults. These fault systems facilitate the migration and distribution of post-volcanic emissions, reaching the surface as mofettes or in mineral water springs. Based on review of existing literature and previous studies on greenhouse gases natural emissions, we made a preliminary inventory of relevant sites that can constitute natural laboratories for the study of CO2 geological storage. In order to confirm sites suitability, we conducted two field campaigns, one for each zone, in September and October 2019. Within these campaigns, apart from localization of the sites, we also made soil gas and high precision GPS measurements for the assessment of CO2 emissions. In Harghita zone, we investigated the following sites with natural CO2 emissions: Harghita Bai, Selters, Sântimbru Bai, Baile Apor, Sulphur Cave, Lazarești and Tușnad. Apart from Baile Apor (Balvanyios) and Lazarești, all the other sites presented covered mofettes, built as dry spas. It is worth mentioning that these mofettes constitute important points of touristic attraction within the spas developed over centuries around them and the carbo-gazeous springs. The CO2 concentration in these mofettes, as measured during the field campaign, exceeds 98% CO2. In Baile Apor (Balvanyios) site, the mofettes are not covered and present high CO2 concentrations, but the site is an important touristic attraction of the area and of the country and is highly frequented by tourists, therefore its use as laboratory can be problematic. The only site that we found suited as natural laboratory in Harghita is Lazarești, in the Cozmeni commune. Within this site we have localized several dry and wet mofettes, with CO2 concentrations exceeding 40%. For Banat zone, we investigated only three sites: Buziaș, Sacoșu Mare and Seceani. For Buziaș, the two mofettes are included in the spa facilities of a hotel and used for therapeutic purposes, under strict medical supervision. At Sacoșu Mare, although preliminary indicated as natural CO2 emission site, we were unable to localize any mofette. South of Seceani village (north of Timișoara city) we have identified as potential natural laboratory a partially marshy area with a large areal extent. On this area we have found several mud volcanoes and dry mofettes. The CO2 emissions are low, mainly due to the seasonal character of mud volcanoes activity which, according to previous findings, has its peak in the spring and a low in autumn, when the field measurement campaign took place. The activity of the mud volcanoes and therefore the mofettic emissions are strongly connected to the hydrological regime. In the selected natural laboratories, Lazarești for Harghita zone and Seceani for Banat zone we intend to make in the next two years a complex geological, geochemical, geophysical and environmental study. The objectives are to define the local geophysical model and improve the geological model, identifying all the migration pathways for the mofettic gases, to make an integrated environmental impact assessment and to identify early indicators for the presence of CO2.

Climatology and Evolution of the Antarctic Peninsula Föhn Wind‐Induced Melt Regime From 1979–2018

AbstractWarm and dry föhn winds on the Antarctic Peninsula (AP) cause surface melt that can destabilize vulnerable ice shelves. Topographic funneling of these downslope winds through mountain passes and canyons can produce localized wind‐induced melt that is difficult to quantify without direct measurements. Our Föhn Detection Algorithm (FöhnDA) identifies the surface föhn signature that causes melt from measurement by 12 Automatic Weather Stations on the AP, that train a machine learning model to detect föhn in 5 km Regional Atmospheric Climate Model 2 (RACMO2.3p2) simulations and in the ERA5 reanalysis model. We estimate the fraction of AP surface melt attributed to föhn and possibly katabatic winds and identify the drivers of melt, temporal variability, and long‐term trends and evolution from 1979–2018. We find that föhn wind‐induced melt accounts for 3.1% of the total melt on the AP and can be as high at 18% close to the mountains where the winds funnel through mountain canyons. Föhn‐induced surface melt does not significantly increase from 1979–2018, despite a warmer atmosphere and more positive Southern Annular Mode. However, a significant increase (+0.1 Gt y‐1) and subsequent decrease/stabilization occur in 1979–1998 and 1999–2018, consistent with the AP warming and cooling trends during the same time periods. Föhn occurrence, more than föhn strength, drives the annual variability in föhn‐induced melt. Long‐term föhn‐induced melt trends and evolution are attributable to seasonal changes in föhn occurrence, with increased occurrence in summer, and decreased occurrence in fall, winter, and early spring over the past 20 years.

Spatial prediction of spring locations in data poor region of Central Himalayas

Abstract This research explores the methods for understanding groundwater springs distribution and occurrence using Geographic Information System (GIS) and Machine Learning technique in data poor areas of the Central Himalayas. The objectives of this study are to analyse the distribution of natural springs, evaluate three random forest models for its predictability and establish a model for the prediction of occurrence of springs. This study evaluates the primary causal factors for occurrence of springs. The data used in this study consists of 20 parameters based on topography, geology, lithology, hydrology and land use as causal factors, whereas 621 spring location and discharge (n = 621) measured during 2014–2016 and 815 non-spring locations (generated by GIS tool) use as supporting evidence to train (80%) and test (20%) the prediction model. Results show that the Bootstrap method is comparatively reliable (92% accuracy) over Boosted tree (64% accuracy) and Decision tree (74% accuracy) methods to classify and predict the occurrence of springs in the watershed. Bootstrap Forest shows the high Prediction rate for True Positive (82% actual spring predicted as a spring) and True Negative (89% actual non-spring predicted as non-spring), and the model seems consistent in both responses. This model was then applied to an independent dataset to predict spring location estimates with 75% accuracy. Therefore, spatial statistical methods prove efficient at predicting spring occurrence in data poor regions.

Medium to low enthalpy geothermal reservoirs estimated from geothermometry and mixing models of hot springs along the Malawi Rift Zone

We investigated the major ion and stable isotope geochemistry and used silica and cation concentrations to assess the geothermometry of hot springs along the Malawi Rift Zone (MRZ). The MRZ is a magma-poor rift, where potential geothermal energy is postulated from elevated heat flow and the occurrence of hot springs. Our objectives were to (1) estimate hot spring reservoir temperatures, (2) identify processes that could affect hot spring water during the ascent from their geothermal reservoirs, and (3) identify the most promising areas for geothermal energy generation. New geochemistry data from 27 hot springs were analyzed and classified as Na-HCO3, Na-SO4, or Na-Cl (SO4) water types controlled mainly by the mineralogy of the host rocks. The hot springs in the MRZ are associated with the local meteoric waters that infiltrate at depth and are heated by an anomalously high geothermal gradient. Our findings indicate that a parent geothermal fluid is mixed and diluted with a proportion of more than ∼45 % of cold water from shallow aquifers. Additionally, other processes such as water-rock interaction, and CO2 outgassing take place during the ascent of the geothermal fluid to the surface. The quartz conductive silica geothermometer indicates reservoir temperatures that range from 60 °C to 130 °C, with enthalpies ranging from 250 kJ/kg to 537 kJ/kg, respectively. However, the Na-K cation geothermometer indicates reservoir temperatures from 92 °C to 190 °C with enthalpies from 388 kJ/kg to 808 kJ/kg. Three areas of potential geothermal energy generation were identified: (1) The Chiweta area, (2) Nkhotakota area, and (3) the Shire graben area. We conclude that the hot springs along the MRZ have geothermal energy capabilities of medium to low enthalpy that can be exploited for electricity generation or other direct uses.

An example of environmental, hydrodynamic and hydrobiological features of coastal zone springs of the Baltic: the Roztoka Springs case study

The occurrence of springs in the European Lowlands has not yet been satisfactorily recognised. This is because crenological research focuses mainly on mountainous areas, where springs are common and rich in water. The premise to undertake research on the springs of lowland and postglacial areas in Poland is the fact that they allow the assessment of spring abundance in the areas with geological structure and hydrological conditions different than in the mountains, which is now an extremely important argument. The study presents preliminary results of research on Roztoka Springs, located in the Polish Lowland in the coastal zone of the South Baltic, covering the hydrogeological, hydrological and hydrobiological issues. The results indicate that the springs are fed from the Quaternary aquifer, in which three hydrostructural zones were distinguished. The third zone (III) with the largest area and water resources is of crucial importance in the recharge of the springs. The yield of the springs is relatively high for young glacial areas, and in summer exceeds 70 dm−3·s−1. The Roztoka Springs have a much larger underground recharge area than it is apparent from the topographic course of the watershed. Bicarbonates dominate the chemical composition of the springs. The primary type of water is calcium-bicarbonate-sulphate. The vegetation corresponds to the difficult environmental conditions and is represented primarily by the Montio-Cardaminetea group. The Roztoka Springs area represents high landscape values. This is why it should be recommended for protection in order to preserve its natural condition, which is threatened by current forest management.

Geological structure identification in Tulehu geothermal prospect area using gravity data analysis

Tulehu is one of geothermal prospect areas located in east Indonesia, which is in Maluku Province. The geological condition of the area is dominated by quaternary volcanic rocks like lava flow, lava dome, and pyroclastic flow, which probably associated with Mt. Eriwakang and Mt. Huwe. But the area is mostly covered by limestone, especially in the southern part of the area. The geothermal prospect of Tulehu is indicated by the occurrence of hot springs spotted along Banda Fault, Banda-Hatuasa Fault, and Huwe Fault in the southern part of Tulehu. In order to understand the subsurface geological structure and its correlation to Tulehu geothermal system, gravity survey was conducted. Gravity survey was carried out using Scintrex CG-5 gravimeter with total of 130 stations were measured with 500 m spacing. The result of CBA and residual gravity indicated the existence of low gravity anomaly at the Mount Eriwakang, while the high gravity anomaly found around several structures obtained from Remote Sensing. Several structures were detected by FHD method, those are Huwe Fault, Banda Fault, Tulehu Fault, and Wayari Fault. Based on SVD method, the type of faults are identified. These structures also supported through 2-D gravity forward modeling. The 2-D gravity modeling results several layers that build the geothermal system of Tulehu, those are Limestone with density of 1.79 g/cc, Pyroclastic with density of 2.67 g/cc, Andesitic Lava with density of 2.6 g/cc, claycap with density of 2.2 g/cc, and Basement with density of 2.81 g/cc.

The application of selected hydrochemical indicators in the interpretation of hydrogeochemical data – A case study from Busko-Zdrój and Solec-Zdrój (Poland)

Abstract The processes affecting the formation of the chemical composition of the waters take place in specific hydrochemical zones. The knowledge of such phenomena allows to draw conclusions regarding the origin and conditions prevailing in the regions of their occurrence, e.g. indicate a zone of active water exchange, i.e. an inflow of infiltration waters, or a zone of isolated geological structures, where diagenesis processes take place. The aim of the study was to assess the hydrochemical conditions which affect the formation of chemical composition and genesis of origin of sulfide waters from the Busko-Zdroj and Solec-Zdroj region (Poland) using selected hydrochemical indices (rNa+/rCl−, rNa+/rK+, rNa+/(rNa++rCl−), rSO42− × 100/rCl−, rCl−/rBr−, rHCO3−/rCl− and the weight index: Cl−/Br−). A detailed analysis was carried out for sulfide waters from fifteen intakes and five springs. Several aquifer systems are found in the study area. Investigated intakes and springs differ in terms of stratigraphy and lithology. The analysis of changes in the values of selected hydrochemical indices confirms that waters of the Busko-Zdroj and Solec-Zdroj region belong to two systems of circulation — “shallow” and “deep”. The formation of the chemical composition of analysed waters occurs mainly in the aquifer. The values of rNa+/rCl−, rCl−/rBr−, rNa+/(rNa++rCl−), and Cl−/Br− indices suggest that the salinity of sulfide waters may result from leaching of salt interburdens and inclusions. In the area of occurrence of sulfide springs, tectonic cracking zones enable the inflow of highly mineralized waters and thus contribute to the mixing of waters of different aquifers. High content of Cl− and Na+ ions as well as mineralization higher than in sea waters indicate the formation of waters from the upper Cretaceous level together with deposits in a sedimentary basin.

Hybrid Prediction of Weekly Tornado Activity Out to Week 3: Utilizing Weather Regimes

AbstractTornadoes are one of the high‐impact weather phenomena that can induce life loss and property damage. Here, we investigate the relationship between large‐scale weather regimes and tornado occurrence in boreal spring. Results show that weather regimes strongly modulate the probability of tornado occurrence in the United States due to changes in shear and convective available potential energy and that persisting weather regimes (lasting ≥3 days) contribute to greater than 70% of outbreak days (days with ≥10 tornadoes). A hybrid model based on the weather regime frequency predicted by a numerical model is developed to predict above/below normal weekly tornado activity and has skill better than climatology out to Week 3. The hybrid model can be applied to real‐time forecasting and aide in mitigation of severe weather events.

Characterization of Aquifers in Metamorphic Rocks by Combined Use of Electrical Resistivity Tomography and Monitoring of Spring Hydrodynamics

Crystalline rocks are generally characterized by negligible porosity and permeability in terms of groundwater exploitability. However, alteration processes can greatly increase their fracture permeability and induce formation of modest, but locally important aquifers. Therefore, subsurface characteristics of alteration zones are of major importance for hydrogeological evaluation of crystalline terrains. Alteration processes greatly affect rock total porosity and water content, causing contrasting electrical resistivity of rocks affected by varying degrees of weathering. This makes electrical resistivity tomography (ERT) a preferable geophysical method for the exploration of alteration zones in crystalline rocks. In our research, we used an integrated approach, combining the ERT method with monitoring of spring discharge and hydrochemistry to characterize metamorphic aquifers on slopes of the Medvednica Mountain (Croatia). Significant fracture flow aquifers are found to be formed in intensely fractured but not highly weathered rock masses (medium to high resistivity values), while highly weathered masses (low resistivity values) form local barriers for fracture flows. Subsurface structure of the alteration zone proved to be highly irregular, with sharp contacts between more and less weathered rocks. Decrease of permeability below the alteration zone keeps the water level near the surface and enables spring occurrence on the mountain slopes. Studied aquifers have relatively limited extent, resulting in typical capacity of major springs of a few l/s. More frequent but less productive springs are attributed to the draining of the shallow part of the alteration zone (mostly saprolite). Combination of the ERT method with spring monitoring proved to be very effective as a first and relatively inexpensive methodology for hydrogeological characterization of crystalline terrains, both in local and catchment scales.

Mapping of Groundwater Spring Potential in Karst Aquifer System Using Novel Ensemble Bivariate and Multivariate Models

Groundwater is an important natural resource in arid and semi-arid environments, where discharge from karst springs is utilized as the principal water supply for human use. The occurrence of karst springs over large areas is often poorly documented, and interpolation strategies are often utilized to map the distribution and discharge potential of springs. This study develops a novel method to delineate karst spring zones on the basis of various hydrogeological factors. A case study of the Bojnourd Region, Iran, where spring discharge measurements are available for 359 sites, is used to demonstrate application of the new approach. Spatial mapping is achieved using ensemble modelling, which is based on certainty factors (CF) and logistic regression (LR). Maps of the CF and LR components of groundwater potential were generated individually, and then, combined to prepare an ensemble map of the study area. The accuracy (A) of the ensemble map was then assessed using area under the receiver operating characteristic curve. Results of this analysis show that LR (A = 78%) outperformed CF (A = 67%) in terms of the comparison between model predictions and known occurrences of karst springs (i.e., calibration data). However, combining the CF and LR results through ensemble modelling produced superior accuracy (A = 85%) in terms of spring potential mapping. By combining CF and LR statistical models through ensemble modelling, weaknesses in CF and LR methods are offset, and therefore, we recommend this ensemble approach for similar karst mapping projects. The methodology developed here offers an efficient method for assessing spring discharge and karst spring potentials over regional scales.

Enhanced Characterization of Water Resource Potential in Zaghouan Region, Northeast Tunisia

This study presents a range of approaches to achieve enhanced characterization of the Zaghouan aquifer system (northeastern Tunisia). Existing water borehole data were analyzed to identify the different reservoir formations, while satellite imagery is analyzed to determinate the superficial lineaments affecting these formations. To define the deep structures determining the geometry of the Zaghouan aquifer system, lithostratigraphic correlations were constructed and analyzed supported by both quantitative and qualitative assessment of gravity measurements. The available lithological columns and their corresponding well logs reveal different carbonate and detritic reservoirs. The carbonate reservoirs consist of Jurassic, Cretaceous and Eocene limestones, whereas the detritic ones are composed of Oligo–Miocene sandstones and Plio-Quaternary to Quaternary sands and gravels. The structural map obtained from processing the satellite imagery confirms several lineaments drawn on the geological map, such as the Zaghouan fault, but also reveals new ones hitherto unrecognized. The intersections of the detected lineaments explain the occurrence of many springs in the area offering potentially favorable opportunities for accessing water resources in fractured aquifers. Analysis of lithostratigraphic correlations shows notable variations in the thickness, depth and composition of reservoir formations. Gravity data interpretation gives more precision by highlighting buried structures and discontinuities with different directions and depths. The delineated tectonic features demonstrate an aquifer system compartmentalized in raised and subsided blocks. The raised compartments may constitute continental divide areas and preferential aquifer recharge zones, while the sunken ones contain a multilayer aquifer composed of Quaternary and Pliocene reservoirs overlying multiple permeable layers, Tertiary and/or Mesozoic in age.

Evaluating CO2 flux and recharge source in geothermal springs, Garhwal Himalaya, India: stable isotope systematics and geochemical proxies.

Evaluation of geogenic carbon fluxes between solid Earth and its atmosphere is essential to understand the global geological carbon cycle. Some of the key geogenic CO2 suppliers are the magmatic mantle and metamorphic degassing from active and quiescent volcanoes, fault zones, geothermal systems and CO2 rich groundwater. Indian Himalayan geothermal field hosts about 340 geothermal springs in natural as well as artesian condition that eject hot waters and volatiles with varied temperature and chemical composition. These sites provide an opportunity to analyse tectonically driven gas emissions and their impact on regional and global climate. Here we adopt a method for direct measurement of Dissolved Inorganic Carbon (DIC ≈ HCO3) concentration in the geothermal springs to estimate geogenic CO2 flux from an active region based on water discharge and area of geothermal system between the tectonic boundaries of the Main Central Thrust (MCT) and Main Boundary Thrust (MBT) of the Garhwal (Northwest) Himalaya. In the study area, geothermal spring water contain high δ13CDIC ratio (- 8.5‰ to + 4.0‰ VPDB), and among the major ions, bicarbonate (HCO3-) varies by an order of magnitude from 1697 to 21,553μEq/L; chloride and sodium vary from 90 to 19,171μEq/L and 436 to 23181μEq/L. The elevated concentration of Cl- and Na+ in geothermal spring waters suggests affinity towards their deeper origin. These geothermal springs cover a large area of nearly 10,000km2 of the Garhwal region showing a significant discharge of CO2 rich water with an estimated carbon dioxide degassing flux of ~7.2 × 106mol/year to the atmosphere. Considering widespread occurrences of geothermal springs in tectonically active areas worldwide, the proposed direct measurement of DIC may be used as a reliable tool to estimate CO2 fluxes in different active orogenic settings within the Earth system. Results of stable isotopes of δ18O (VSMOW) and δD (VSMOW) in these geothermal spring waters follow the Global Meteoric Water Line (GMWL), suggesting affinity of their recharge through the meteoric origin.

Seasonal variation and driving factors of forest fire in Zhejiang Province, China, based on MODIS satellite hot spots

Understanding the changes and driving factors of forest fire can provide scientific basis for prevention and management of forest fire. In this study, we analyzed the changes and driving factors of forest fire in Zhejiang Province during 2001-2016 based on trend analysis and Logistic regression model with the MODIS satellite fire point data combined with meteorological (daily ave-rage wind speed, daily average temperature, daily relative humidity, daily temperature difference, daily cumulative precipitation), human activities (distance from road, distance from railway, distance from resident, population, per capita GDP), topographic and vegetation factors (elevation, slope, vegetation coverage). The results showed that the number of forest fires in spring and summer had significantly increased, while the forest fires in the autumn and winter increased first and then decreased. Forest fire in autumn significantly declined. The four seasons' fire occurrence prediction models had good prediction accuracy, reaching 75.8% (spring), 79.1% (summer), 74.7% (autumn) and 79.6% (winter). The meteorological, human activity, topographic and vegetation factors significantly affected fire occurrence in spring and summer, while meteorological factors were the main fire drivers in autumn and winter in Zhejiang. The focus of forest fire management should be on human activities. Fire prevention campaign should be done in spring and summer when high-risk forest fires were scattered in the study area. In autumn and winter, observatory and monitoring equipment could be built to facilitate fire management and detect in the area of high fire risk that was concentrated in the southwest region.

Saturated areas through the lens: 2. Spatio‐temporal variability of streamflow generation and its relationship with surface saturation

AbstractInvestigating the spatio‐temporal variability of streamflow generation is fundamental to interpret the hydrological and biochemical functioning of catchments. In humid temperate environments, streamflow generation is often linked to the occurrence of near stream surface saturated areas, which mediate hydrological connectivity between hillslopes and streams. In this second contribution of a series of two papers, we used salt dilution gauging to investigate the spatio‐temporal variability of streamflow in different subcatchments and for different reaches in the Weierbach catchment (0.42 km2) and explored the topographical controls on streamflow variability. Moreover, we mapped stream network expansion and contraction dynamics. Finally, we combined the information on the spatio‐temporal variability of streamflow with the characterization of riparian surface saturation dynamics of seven different areas within the catchment (mapped with thermal infrared imagery, as presented in our first manuscript). We found heterogeneities in the streamflow contribution from different portions of the catchment. Although the size of the contributing area could explain differences in subcatchments' and reaches' net discharge, no clear topographic controls could be found when considering the area‐normalized discharge. This suggests that some local conditions exert control on the variability of specific discharge (e.g., local bedrock characteristics and occurrence of perennial springs). Stream network dynamics were found not to be very responsive to changes in catchment's discharge (i.e., total active stream length vs. stream outlet discharge relationship could be described through a power law function with exponent = 0.0195). On the contrary, surface saturation dynamics were found to be in agreement with the level of streamflow contribution from the correspondent reach in some of the investigated riparian areas. This study represents an example of how the combination of different techniques can be used to characterize the internal heterogeneity of the catchment and thus improve our understanding of how hydrological connectivity is established and streamflow is generated.

Forecaster Perceptions and Climatological Analysis of the Influence of Convective Mode on Tornado Climatology and Warning Success

Tornadogenesis occurs in a variety of storm types, or convective modes, each having a unique climatology and challenges in their detection and warning. Some warnings result in false alarms, meaning that no tornado occurred within the warning polygon. We used a mixed-methods approach to assess how convective mode––discrete supercell, cell in cluster, cell in line, or quasi-linear convective system (QLCS)––affects the tornado climatology and National Weather Service (NWS) procedures within three County Warning Areas (CWAs): Memphis (MEG), Nashville (OHX), and Morristown (MRX), Tennessee. We used three data sets: tornadoes (2003–2014) categorized by convective mode, false alarms (2012–2016) categorized by convective mode, and eleven interviews of NWS forecasters. The CWAs had no significant difference in mode frequency when removing replication from multiple-tornado events. However, when outbreaks were included, discrete supercell and QLCS signals were identified in MEG and OHX, respectively. Convective mode, season, and time of day were strongly associated. Tornadic discrete supercells followed a traditional severe weather pattern of spring and daytime occurrences and caused fewer false alarms. More QLCS tornadoes happened at night and in winter. Cells in lines and clusters accounted for larger proportions of events in the false-alarm data set than the tornado data set. Forecasters noted challenges in detecting tornadoes in convective modes other than discrete supercells, including short-lived QLCS tornadoes. Key forecaster concerns other than convective mode included storm speed, outbreaks, and lack of ground-truthing at night. Forecasters differed in their motivation to either warn on every tornado or avoid false alarms. Key Words: climatology, false alarm, QLCS, supercell, tornado.

Evidence for intra-plate seismicity from spring-carbonate mound springs in the Kati Thanda–Lake Eyre region, South Australia: implications for groundwater discharge from the Great Artesian Basin

The relationship between fault structures and Great Artesian Basin (GAB) spring occurrence has rarely been discussed in relation to intra-plate seismicity. This is despite the occurrence of mound springs in the southwest portion of the GAB in South Australia being previously linked with the occurrence of faulting and the many studies concerning the role that tectonics plays in the formation and ongoing maintenance of spring activity. This study examines the correlation between seismicity and spring occurrences within the southwestern GAB, as well as field evidence for the relationship between ongoing spring activity and intra-plate seismicity. It was found that spring formation within the southwestern GAB is correlated with an interpreted northwest–southeast, left-lateral transpressional shear zone that is related to the Adelaide Fold Belt underlying the GAB. The influence of seismicity at these sites is implied through the propagation of deformation structures and lineaments concordant with interpreted underlying regional structures. In zones of reactivation, these structures and lineaments develop networks that readily form conduits for the migration of groundwater. Consequently, the spring-carbonate-depositing springs of the southwestern GAB have potential as a record for intra-plate tectonic activity associated with the northern portion of the underlying Adelaide Fold Belt. The work presented here re-enforces the importance of considering the effect that faulting has on groundwater flow paths and interconnectivity with either overlying or underlying aquifers within the southwestern GAB.

High Throughput Bioacoustic Monitoring and Phenology of the Greater Noctule Bat (Nyctalus lasiopterus) Compared to Other Migratory Species

Conventional monitoring tools are seldom effective for studying the ecology of rare and elusive mammals. In the present study, we use automated ultrasound detectors to provide information about seasonal activity of the greater noctule bat (Nyctalus lasiopterus), the largest and one of least known European bats. We selected localities within Central Europe with diverse geomorphological contexts, including rivers of different sizes and mountain passes. The study demonstrates the capability of the automatic recording approach to achieve bioacoustic discrimination of this species, but also pointed to the persistent need of integrating results from automatic classification software applications with the feedback from manual approaches. The high throughput capacity of the assay proved to be efficient, and the regular occurrence of the species was identified at two localities. These locations are associated with two known and intensely used migratory corridors of winged animals going through Vltava River valley and Cervenohorske Saddle in Jeseniky mountains, as illustrated also by the activity patterns of other migratory species. Together with the occurrence of spring and autumn peaks in activity, these findings are in concordance with the plesiomorphic condition in pipistrelloid bats, showing also migratory behavior, and represent further indirect evidence of migration of the greater noctule. This pattern could be facilitated by the trophic niche of the species, involving predation of migrating songbirds. Differences in phenology of migratory species observed at particular sites likely mirror position of the locality in relation to migration flyways, seasonal and geographic variation in prey availability and energy demands etc. Further application of bioacoustic monitoring and other tools is necessary to obtain detailed information about the range and movement ecology of the species in higher latitudes.

Evaluating the thermal stratification of Köyceğiz Lake (SW Turkey) using in-situ and remote sensing observations

The goal of this study is to evaluate the thermal properties of Köyceğiz Lake using in-situ measurements and satellite based thermal infrared imagery. In-situ measurements of surface water temperature and water depth, as well as meteorological data, were used in the analysis. Images of the Landsat 8 TIRS (Thermal Infrared (IR) Sensors) at IR channels were taken from the data archives of United State Geological Survey (USGS), and were validated with surface in-situ measurements. Specific Electrical conductivity (SEC) measurements done at the bottom of the lake were also used for a better understanding of the water thermal stratification and types (cold/hot) that impact on the underwater physical properties of the lake. In-situ measurements at the water surface were interpolated using a new method known as ‘Empirical Bayesian Kriging (EBK)’. The 2D and 3D (dimensional) temperature maps were generated using the Delaunay triangulation technique which utilizes nearest neighbor interpolation method. The results show that the correlation coefficient (R2) between water surface temperatures (WST) from in-situ measurements and IR channels is found to be greater than 0.86. The analysis of 2D and 3D temperature mapping of the lake water revealed evidences for subaqueous cold spring occurrence in the northern part and subaqueous hot springs in the south-western part of Koycegiz Lake. It is concluded that correlating in-situ water temperature measurements to Landsat 8 TIRS images is an efficient method for temporal and spatial evaluation of lake water characteristics.