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During the flow of stream water from losing reaches through aquifer sediments, aerobic and anaerobic respiration (denitrification) can deplete dissolved oxygen and nitrate (NO3−), impacting water quality in the floodplain and downstream gaining reaches. Such processes, which vary in time with short and long‐term changes in stream flow and temperature, need to be assessed at the stream corridor scale to fully capture their effects on net turnover, but this has rarely been done. To address this gap, we combine a fully‐integrated 3D transient numerical flow model with temperature‐dependent reactive transport along advective subsurface flow paths to assess aerobic and anaerobic respiration dynamics at the stream corridor scale in a predominantly losing stream. Our results suggest that given carbon availability (as an electron donor), complete NO3− removal occurred further away from the stream after complete oxygen depletion and was relatively insensitive to variations in temperature and transit‐times. Conversely, transit‐times and oxygen concentrations constrained nitrate removal along short hyporheic flow paths. Even under limited carbon availability and low‐temperatures, NO3− removal fractions (RNO3) will be greater at locations further from the stream than along shorter hyporheic flow paths (RNO3 = 0.4 and RNO3 = 0.1, respectively). With increasing temperature, the relative effects of stream flow and solute concentrations on biogeochemical turnover and the redox zonation around the stream decreased. The study highlights the importance of seasonal variations of stream flow and temperature for water quality at the stream‐corridor scale. It also provides an adaptive framework to assess and quantify reach‐scale biogeochemical turnover around dynamic streams. Plain Language Summary: Nitrate pollution is a widespread problem in many catchments with intense agricultural activities. Denitrification is a redox process that removes nitrate from the aquatic system via its transformation to nitrogen gas. Denitrification is difficult to assess at larger scales since it depends on multiple factors, such as solute concentrations, temperature variations, and also the time that water resides in the subsurface, where reactions can take place. To evaluate how these factors can influence denitrification, we employed a coupled modeling approach representing the riparian zone of a 4th order stream in central Germany. We found that temperature variations strongly regulate the process and that during the winter the aerobic (oxygen rich) zone around the stream expands, which further inhibits denitrification in the near stream groundwater. However, even in the winter denitrification occurs, but at larger distance from the stream where oxygen has been depleted sufficiently. With increasing temperature, the influence of other factors on denitrification and on the redox zonation around the stream decreases. Coupled numerical models can provide further insights into the occurrence and interrelations of the multiple processes controlling water quality patterns in river corridors. Key Points: Fully‐integrated 3D transient flow model coupled to a temperature‐dependent flow path‐reaction model to assess riparian solutes turnoverTurnover mainly controlled by high temperature in summer; in winter solute concentrations and transit‐times variations become more importantAssessments of riparian turnover restricted to near stream areas might overlook processes affecting overall downstream water quality [ABSTRACT FROM AUTHOR]

Background: Forests perform various important ecosystem functions that contribute to ecosystem services. In many parts of the world, forest management has shifted from a focus on timber production to multi-purpose forestry, combining timber production with the supply of other forest ecosystem services. However, it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services. Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition, we develop models to predict the potential supply of 13 ecosystem services. We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data. Results: Looking at the potential supply of ecosystem services, we found trade-offs (e.g. between both bark beetle control or dung decomposition and both productivity or soil carbon stocks) as well as synergies (e.g. for temperature regulation, carbon storage and culturally interesting plants) across the 53 most dominant forest types in Germany. No single forest type provided all ecosystem services equally. Some ecosystem services showed comparable levels across forest types (e.g. decomposition or richness of saprotrophs), while others varied strongly, depending on forest structural attributes (e.g. phosphorous availability or cover of edible plants) or tree species composition (e.g. potential nitrification activity). Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions. However, the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species. Conclusions: Our results show that forest multifunctionality is limited to subsets of ecosystem services. The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level, when stands of complementary forest types are combined. These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales. [ABSTRACT FROM AUTHOR]

The flowering phenology of Coltsfoot (Tussilago farfara L.) shows a very strong negative response to warmer temperatures in spring (warmer springs = earlier flowering) as reported in numerous studies for other species in Europe and North America. However, despite this, flowering dates in some locations have failed to show a strong advance and, in a small number of cases, have even shown significant delays. Here we use a very extensive data set on first flowering dates (FFD) of Coltsfoot in Germany, firstly on a national scale in the period 1894–2015 and secondly at a regional level in the more thoroughly recorded period from 1951–2015. FFDs were coupled with gridded temperature data using regression techniques to attempt to understand the reasons for the unexpected changes in phenology. National mean FFD did not change significantly over 122 years, although January–March mean temperatures had warmed by 1.2°C. The flowering‐temperature model was significantly improved when the previous September mean temperature was included, which decreased the overall temperature response from 4.5 to 3.7 days/°C. For the more thoroughly recorded period of 1951–2015, January–March mean temperature warmed significantly by 1.7–2.4°C in all 11 German federal state combinations and mean FFD dates advanced by 3–14 days, significant for seven of the States. For 10 of the 11 States, multiple linear regressions explained 79–89% of the observed variation in FFD and evidenced a positive relationship (significant in half of these) with higher temperature in the September preceding flowering (warmer September = later flowering). However, the scale of the September influence is insufficient to explain why Coltsfoot flowering may have stalled or been delayed. The use of controlled experiments to supplement observational data may be necessary to fully understand the drivers of Coltsfoot flowering in spring. [ABSTRACT FROM AUTHOR]

Exploration activities for hydrocarbons and thermal waters between the 1960s and 1980s consolidated the assumption of a positive temperature anomaly in the Franconian Basin of SE Germany. However, the geological causes of the temperature high are not known yet. In addition, an up-to-date compilation of temperature data from deep wells and thermal conductivity data of the Permo-Triassic section and of the basement rocks is lacking. In this study, we present a homogenised dataset of uniformly corrected temperature readings from 18 deep wells and new thermal conductivity data of the key strata of the Franconian Basin to constrain the geometry of the anomaly and to calculate reliable conductive surface heat flow densities. We further apply a vertical Péclet number analysis on equilibrated temperature logs for quantifying convective and conductive components in heat transfer. The isotherms of calculated equilibrium temperature gradients >30.0-48.9 °C km-1 constrain the presence of elevated temperatures in the Franconian Basin within an area of ~100 × 65 km². The elevated temperatures in the centre of the anomaly presumably originate in the basement but rapidly decrease away from the centre. The geothermal potential of the area is locally high, with surface heat flows exceeding 100 mW m-2 and reaching a maximum of 134 (±16) mW m-2 in the central part of the anomaly. The NW-SE elongated shape of the anomaly implies that the strike of the major regional fault system has a significant control on the present-day temperature field. A Péclet number analysis and the correlation of T-log breaks with the new thermal conductivity data prove a predominantly conductive heat transfer regime. However, signatures of convective heat transfer have been proven for the aquifers of the Buntsandstein, Muschelkalk and Keuper groups. The study also reveals significant data gaps in the Franconian Basin, which strongly limit a reliable three-dimensional representation of the temperature field and a further limitation of possible cause(s) of the temperature anomaly. Namely, these are missing temperature data of the basement and a generally low density and the partially low depth level of available temperature data. [ABSTRACT FROM AUTHOR]

Background: Temperature control is recommended after out of hospital cardiac arrest (OHCA) by international guidelines. This survey aimed to investigate current clinical practice and areas of uncertainty., Methods: Online survey targeting members of three medical emergency and critical care societies in Germany (April 21-June 6, 2022) assessing post-cardiac arrest temperature control management., Results: Of 341 completed questionnaires 28% (n = 97) used temperature control with normothermic target and 72% (n = 244) temperature control with hypothermic target. The definition of fever regarding patients with cardiac arrest ranged from ≥ 37.7 to 39.0 °C. Temperature control was mainly started in the ICU (80%, n = 273) and most commonly core cooling (74%, n = 254) and surface cooling (39%, n = 134) with feedback were used. Temperature control was maintained for 24 h in 18% (n = 61), 48 h in 28% (n = 94), 72 h in 42% (n = 143) and longer than 72 h in 13% (n = 43). 7% (n = 24) were using different protocols for OHCA with initial shockable and non-shockable rhythm. Additional 14% (n = 48) were using different temperature control protocols after in-hospital cardiac arrest (IHCA) compared with OHCA. Overall, 37% (n = 127) changed practice after the publication of the ERC-2021 guidelines and 33% (n = 114) after the recent publication of the revised ERC-ESICM guideline on temperature control., Conclusions: One-third of the respondents changed clinical practice since recent guideline update. However, a majority of physicians further trusts in temperature control with a hypothermic target. Of interest, 14% used different temperature control strategies after IHCA compared with OHCA and 7% for shockable and non-shockable initial rhythm. A more individualized approach in post resuscitation care may be warranted., (© 2023. The Author(s).)

As a result of ongoing climate change and more frequent heat events, the regulating services of land cover in terms of moderating and mitigating local temperatures are increasingly important. While the reduced temperatures found in forests and wetlands are recognized, their wider contribution to regional landscape cooling remains largely uncharacterized and unquantified. Herein, we propose and test a new method that estimates the temperature response and inertia of landscapes in high temperatures, based on land cover share. In order to achieve this goal, we combined the MODIS daytime land surface temperature (henceforth LST) time series and CORINE land cover data. We classified the time series in two ways, i.e. by stepwise temperature range (−10/−5 °C to +35/+40 °C) and by the occurrence of hot days (days with a mean LST ≥ 30 °C). As an explanatory variable, we developed and used a greenest pixel composite of the MODIS normalized difference vegetation index (NDVI) time series. In our study area, covering parts of northeastern Germany and western Poland, the fragmented landscape has heterogeneous temperature patterns, including urban heat islands, warm agricultural areas, cool forests and cold wetlands. We found that at high temperature ranges only forests and wetlands remained comparably cool, with LSTs up to 20.8 °C lower than the maximum LST in the study area. The analysis of land cover shares and LSTs revealed the substantial cooling effect of forests and wetlands in line with increasing land cover share in higher temperature ranges, as well as on hot days. The relation between LST and the NDVI indicated vegetation cover as the cause. We propose the corresponding metrics to quantify landscape-level temperature regulation. Equally, we advocate for management to identify these ecosystem services and their current and potential contributions, along with implications for sustaining and increasing, both tree cover and wetlands and thereby adapting landscapes to climate change. [Display omitted] • Land cover share by forests and wetlands predicts mitigation of temperature extremes. • Regulating service: forests and wetlands cool the landscape particularly on hot days. • NDVI measurements indicate that temperature relates to vegetation cover. • Landscape planning and management must incorporate need for temperature management. [ABSTRACT FROM AUTHOR]

This paper presents the findings of a laboratory study of the shear strength and yielding behavior of two glacial till soil deposits from the area of Heiligenhafen, northern Germany. The tests were conducted on reconstituted forms of the soils using a triaxial cell capable of controlling the temperature of the specimens. The experimental program included a series of multi-stage consolidated drained (CD) compression triaxial tests at temperature ranges between 20 and 60 °C. For the temperature range considered in this study, a mild reduction in the effective friction angle of the two till soils of less than 1° was observed due to an increase in temperature from 20 to 60 °C. All the results were carefully assessed in view of the intrinsic soil behavior and fabric, and existing trends are highlighted. The findings of this study provide valuable insights into the shearing properties of till deposits, and can contribute to the enhancement of existing soil constitutive models as well as the development of new models that are particularly suited to the behavior of glacial tills under elevated temperatures. [ABSTRACT FROM AUTHOR]