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The spread of antibiotic resistance is one of the biggest challenges of our time, making it difficult to treat bacterial diseases. Pasteurella multocida is a widespread facultative pathogenic bacterium, which causes a wide range of diseases in both mammals and birds. In the present study, antibiotic susceptibility of 155 P. multocida strains were tested using the broth microdilution method to obtain the minimum inhibitory concentration (MIC) values for 15 antibiotics. The most effective antibiotics against pasteurellosis were ceftiofur, tetracycline, doxycycline, florfenicol and tilmicosin. Of the strains, 12 proved to be multi-drug resistant (MDR). To combat antibiotic resistance, it is important to establish a pre-treatment antibiotic susceptibility profile. A well-chosen antibiotic would not only make the treatment more successful but may also slow down the spread of resistance and the evolution of MDR strains. [ABSTRACT FROM AUTHOR]

Aims: The relative importance of species within an ecosystem shows spatio‐temporal variability related to both the terrain features and numerous rapidly changing factors. Accordingly, functional and species patterns may show some level of persistence, or, due to various disturbances, fluctuations. Communities with high species richness were found to maintain a higher degree of stability than species‐poor or perturbed vegetations; however, diversity and its stability may be spatio‐temporally variable. Based on these considerations, our aim was to assess the responses of a sandy pasture, both species‐wise and at the community level, to the relatively invariant habitat, and to the more rapidly changing environmental conditions. Location: Hungary. Methods: We surveyed the vegetation in an area of about 1 ha by means of high‐resolution spatio‐temporal sampling: we recorded the surface aerial cover (%) of the plant species during 15 campaigns covering spring, summer and autumn aspects for seven years (2013–2019) in 80 × 60 m grids. The biological activity of the ecosystem (above‐ground biomass, soil respiration) was also followed up together with the environmental limiting factors. Results: During the study period, which was characterized by significant warming, the grassland showed a balanced physiological performance with year‐to‐year variability. Fluctuating differentiation of the plant species with different environmental optima along with the terrain attributes was assumed to be responsible for this balanced physiological performance. Although community‐level diversity remained stable, some species favoring cooler, wetter positions disappeared. Conclusions: Terrain features of the study area within 1.5 m or less elevation differences created considerably heterogeneous conditions for a high number (114) of plant species with different ecological needs to co‐occur. The stability of the diversity was found to show terrain relatedness, that is spatial as well as temporal patterns compared to the null model of spatio‐temporal independence, and the ecosystem functions followed these patterns. [ABSTRACT FROM AUTHOR]

Diel variability of soil respiration is influenced by several factors including temperature and carbon allocation as the most significant ones, co-varying on multiple time scales. In an attempt to disentangle their effects we analyzed the dynamics of soil respiration components using data from a three-year soil respiration study. We measured CO2 efflux in intact, root-excluded and root- and mycorrhizal fungi excluded plots and analyzed the diel variability in different phenological stages. We used sine wave models to describe the diel pattern of soil respiration and to disentangle the effects of temperature from belowground carbon allocation based on the differences between component dynamics inferred from the fitted models. Rhizospheric respiration peaked 8–12 hours after GPP peak, while mycorrhizal fungi respiration had a longer time lag of 13–20 hours. Results of δ13CO2 isotopic signals from the respiration components showed similar patterns. It was found that drought affected the component respiration rates differently. Also, the speed and the amount of carbon allocation to the roots as well as to the mycorrhizal fungi was reduced under drought. We conclude that the diel variability of soil respiration is the result of the integrated patterns of temperature- and carbon allocation-driven components in dry grasslands and their share depends on their phenological stages and stress state. [ABSTRACT FROM AUTHOR]

Livestock is both threatened by and contributing to climate change. The contribution of livestock to climate change and greenhouse gas (GHG) emission greatly vary under different management regimes. A number of mitigation options comprise livestock management, although there are a lot of uncertainties as to which management regime to use for a given pedoclimatic and farming system. Therefore, we 1) tested if an extensive cattle livestock farm is a net sink or a net source for GHG (carbon–dioxide, CO 2 ; methane, CH 4 ; nitrous oxide N 2 O) in Central–Eastern Europe, 2) compared the annual GHG balances between the grazed and mowed treatments of the farm 3) and investigated the role of climate variability in shaping these balances. Net ecosystem exchange of CO 2 ( NEE ) was measured with eddy covariance technique in both the grazed and mowed treatments. Estimations of lateral C fluxes were based on management data. Other GHG fluxes (CH 4 , N 2 O) were determined by chamber gas flux measurements technique (in case of soil) and IPCC guidelines (in case of manure decomposition and animal fermentation). Net greenhouse gas balance ( NGHG ) for the grazed treatment was 228 ± 283 g CO 2 equivalent m −2 year −1 (net sink) and −475 ± 144 g CO 2 equiv. m −2 year −1 (net source) for the mowed treatment. Net source activity at the mowed treatment was due to its higher herbage use intensity compared to the grazed treatment. At the farm scale the system was estimated to be a net sink for NGHG in a year with wet (135 g CO 2 equiv. m −2 year −1 ), while a net source in years with dry soil moisture conditions (−267 ± 214 g CO 2 equiv. m −2 year −1 ). We conclude that under a temperate continental climate extended extensive grazing could serve as a potential mitigation of GHG in contrast to mowing. Our study highlights the fact that livestock farming could create a net sink for GHG under proper management regimes. [ABSTRACT FROM AUTHOR]

The process-based biogeochemical model Biome-BGC was enhanced to improve its ability to simulate carbon, nitrogen, and water cycles of various terrestrial ecosystems under contrasting management activities. Biome-BGC version 4.1.1 was used as a base model. Improvements included addition of new modules such as the multilayer soil module, implementation of processes related to soil moisture and nitrogen balance, soil-moisture-related plant senescence, and phenological development. Vegetation management modules with annually varying options were also implemented to simulate management practices of grasslands (mowing, grazing), croplands (ploughing, fertilizer application, planting, harvesting), and forests (thinning). New carbon and nitrogen pools have been defined to simulate yield and soft stem development of herbaceous ecosystems. The model version containing all developments is referred to as Biome-BGCMuSo (Biome-BGC with multilayer soil module; in this paper, Biome-BGCMuSo v4.0 is documented).Case studies on a managed forest, cropland, and grassland are presented to demonstrate the effect of model developments on the simulation of plant growth as well as on carbon and water balance. [ABSTRACT FROM AUTHOR]

Accurate estimation of latent heat flux (LE) based on remote sensing data is critical in characterizing terrestrial ecosystems and modeling land surface processes. Many LE products were released during the past few decades, but their quality might not meet the requirements in terms of data consistency and estimation accuracy. Merging multiple algorithms could be an effective way to improve the quality of existing LE products. In this paper, we present a data integration method based on modified empirical orthogonal function (EOF) analysis to integrate the Moderate Resolution Imaging Spectroradiometer (MODIS) LE product (MOD16) and the Priestley-Taylor LE algorithm of Jet Propulsion Laboratory (PT-JPL) estimate. Twenty-two eddy covariance (EC) sites with LE observation were chosen to evaluate our algorithm, showing that the proposed EOF fusion method was capable of integrating the two satellite data sets with improved consistency and reduced uncertainties. Further efforts were needed to evaluate and improve the proposed algorithm at larger spatial scales and time periods, and over different land cover types. [ABSTRACT FROM AUTHOR]

The process-based biogeochemical model Biome-BGC was enhanced to improve its ability to simulate carbon, nitrogen and water cycles of various terrestrial ecosystems under contrasting management activities. Biome-BGC version 4.1.1 was used as base model. Improvements included addition of new modules such as the multilayer soil module, implementation of processes related to soil moisture and nitrogen balance, soil moisture related plant senescence, and phenological development. Vegetation management modules with annually varying options were also implemented to simulate management practices of grasslands (mowing, grazing), croplands (ploughing, fertilizer application, planting, harvesting), and forests (thinning). New carbon and nitrogen pools have been defined to simulate yield and soft stem development of herbaceous ecosystems. The model version containing all developments is referred to as Biome-BGCMuSo (Biome-BGC with multi-layer soil module). Case studies on a managed forest, cropland and grassland are presented to demonstrate the effect of model developments on the simulation of plant growth as well as on carbon and water balance. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) and net ecosystem exchange (NEE) of a semi-arid grassland (46.69˚N, 19.60˚ E near Bugacpuszta, Hungary) have been measured since 2002 by eddy covariance(EC) technique. The calculation of the turbulent fluxes from the raw (10 Hz) dataset was performed by theEddyPro® open source software. Gap-filling and flux partitioning was accomplished by theREddy ProcWeb online tool (Reichstein et al 2005). Based on the 14 years (2003-2017) long dataset the annual mean evapotranspiration at theBugac site is 488 mm (SD: 77 mm), while the mean annual precipitation for the same periodis 566 mm. The annual sum of ET was less than the annual sum of precipitation except fortwo years (2011, 2012) following a wet extreme year (2010) showing a significant memoryeffect. Mitigating effect of water storage was significant on shorter time scales as well, sinceprecipitation sums during the summer months were exceeded by those of ET indrought/heatwave years (2003, 2007, 2009, 2011, 2012). Strong coupling betweentranspiration and photosynthesis as shown by the strong correlation (R2=0.8618) between theannual sum of ET and GPP was due to high LAI (closed canopy) and more or less constantcover. EC based evapotranspiration data was compared to MODIS Evapotranspiration(MOD16). On annual basis MODIS ET is a close estimation of EC based ET, as the slope ofthe regression between the yearly sums (2003-2013) of MODIS based vs EC based ET is1.0168 (R2=0.6236, RMSE=43.03mm). However, when considering the main growingseason (1 May - 31 July) only, MODIS ET underestimated EC based ET by 10% (R2=0.77,RMSE=22.74), showing that there is a bias on seasonal basis in the MODIS data. Goodnessof fit for the regression of 8-days sums (temporal resolution of MODIS data) in the differentyears range between 0.6913 and 0.8879, while the slope ranges between 0.9271 and 1.2224. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to determine the contributions of autotrophic and heterotrophic components to the total soil CO 2 efflux over three years with high-frequency data acquisition by means of automated measurements. Soil CO 2 efflux was measured continuously by using an automated open system of 10 soil respiration chambers in a sandy grassland in Hungary. Mesh-collar technique was applied to separate the components of the total respiration. Data were collected (1) in root-exclusion (Exr), (2) in root- and mycorrhiza exclusion (Exrm) and (3) in control plots (Exc, roots and mycorrhiza included). We fitted three different models to describe the dependence of total soil CO 2 efflux measured on the Exc (Rs), CO 2 efflux measured on Exr (R TR ) and CO 2 efflux measured on Exrm (R TRM ) on abiotic and biotic drivers. The best fitted model (based on AIC) was later on used in a simulation process. The contribution by rhizospheric respiration (simulated, R rhizo* ) was 36 ± 21%, the contribution by mycorrhizal respiration (simulated, R myc* ) to the total soil respiration was 9 ± 9% while the contribution by heterotrophic respiration (simulated, R het* ) was 55 ± 21% on average. Measured mycorrhizal respiration (R M ) responded to GPP with a time lag of 0–2 days in active period. Drought affected the autotrophic component of soil respiration the most intensively: raise of soil water content resulted in increase of R S by 175% while R TR and R TRM increased by 127% and 93%, respectively. The results highlight the fact that it would be useful to establish and apply separate models for each component. [ABSTRACT FROM AUTHOR]

• Vegetation composition and diversity did not change for six years after the conversion from grazing to mowing. • Even the detailed fine-scale analyses could not reveal differences. • Carbon uptake differed between grazed vs. mowed sites due to biomass removal intensity. • Returning from mowing to grazing would probably restore C uptake because the vegetation composition remained stable. Grasslands could play an important role in supporting livestock, in carbon sequestration and in biodiversity conservation. Different grassland managements may change the vegetation composition of grasslands, which could alter these ecosystem services. We studied the effects of grazing vs. mowing on the vegetation composition (2012–2016) and on the carbon uptake (2011–2013) of sandy grasslands in Hungary to study if the vegetation composition differs and if it does, whether it affects carbon uptake. To observe differences in vegetation composition between the two types of management regimes we performed fine-scale vegetation survey in adjacent grazed and mowed sites. We compared species compositions and vegetation diversity indices between the management regimes based on permutational ANOVA, mixed effect model and information theory models. We used fine-scale vegetation survey because it has the potential to indicate vegetation changes within six years as changes in species richness and diversity are usually detected after 10–20 years. Carbon uptake was measured in parallel with eddy covariance technique at both sites. In spite of the contrasting management regimes the vegetation composition was stable (no differences observed in the diversity indices), while carbon uptake was significantly greater in the grazed (sink: +1 ± 0.7 t C ha−1 year−1) compared to the mowed site (source: -0.3 ± 0.6 t C ha−1 year−1). The vegetation was heterogeneous (patchy) and had a high species richness at both sites (grazed: 91 species ha−1, mowed: 90 species ha−1) which might have contributed to the stability of the vegetation composition. We concluded that differences in carbon uptake existed between the grazed vs. mowed sites due to biomass removal intensity with no differences in the vegetation composition. [ABSTRACT FROM AUTHOR]

High spatial resolution and geolocation accuracy canopy evapotranspiration (ET) maps are well suited tools for evaluation of small plot field trials. While creating such a map by use of an energy balance model is routinely performed, the acquisition of the necessary imagery at a suitable quality is still challenging. An UAV based thermal/RGB integrated imaging system was built using the RaspberryPi (RPi) microcomputer as a central unit. The imagery served as input to the two-source energy balance model pyTSEB to derive the ET map. The setup's flexibility and modularity are based on the multiple interfaces provided by the RPi and the software development kit (SDK) provided for the thermal camera. The SDK was installed on the RPi and used to trigger cameras, retrieve and store images and geolocation information from an onboard GNSS rover for PPK processing. The system allows acquisition of 8 cm spatial resolution thermal imagery from a 60 m height of flight and less than 7 cm geolocation accuracy of the mosaicked RGB imagery. Modelled latent heat flux data have been validated against latent heat fluxes measured by eddy covariance stations at two locations with RMSE of 75 W/m 2 over a two-year study period.