Rain-fed pastoral systems are tightly connected to meteorological conditions. It is, therefore, likely that climate change, including changing atmospheric CO2 concentration, temperature, ...precipitation and patterns of climate extremes, will greatly affect pastoral systems. However, exact impacts on the productivity and carbon dynamics of these systems are still poorly understood, particularly over longtime scales. The present study assesses the potential effects of future climatic conditions on productivity and soil organic carbon (SOC) stocks of mowed and rotationally grazed grasslands in France. We used the CenW ecosystem model to simulate carbon, water, and nitrogen cycles in response to changes in environmental drivers and management practices. We first evaluated model responses to individual changes in each key meteorological variable to get better insights into the role and importance of each individual variable. Then, we used 3 sets of meteorological variables corresponding to 3 Representative Concentration Pathways (RCP 2.6, RCP 4.5 and RCP 8.5) for long-term model runs from 1975 to 2100. Finally, we used the same three RCPs to analyze the responses of modelled grasslands to extreme climate events. We found that increasing temperature slightly increased grasslands productivities but strongly reduced SOC stocks. A reduction in precipitation led to reductions of biomass and milk production but increased SOC. Conversely, doubling CO2 concentration strongly increased biomass and milk production and marginally reduced SOC. These SOC trends were unexpected. They arose because both increasing precipitation and CO2 increased photosynthetic carbon gain, but they had an even greater effect on the proportion of biomass that could be grazed. The amount of carbon remaining on site and able to contribute to SOC formation was actually reduced under both higher precipitation and CO2. The simulations under the three RCPs indicated that grassland productivity was increased, but that required higher N fertilizer application rates and also led to substantial SOC losses. We thus conclude that, while milk productivity may continue at current rates under climate change, or even increase slightly, there could be some soil C losses over the 21st century. In addition, under the highest-emission scenario, the increasing importance of extreme climate conditions (heat waves and droughts) might render conditions at our site in some years as unsuitable for milk production. It highlights the importance of tailoring farming practices to achieve the dual goals of maintaining agricultural production while safeguarding soil C stocks.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Despite higher rates of revision after total hip arthroplasty (THA) being reported for uncemented stems in patients aged > 75 years, they are frequently used in this age group. Increased mortality ...after cemented fixation is often used as a justification, but recent data do not confirm this association. The aim of this study was to investigate the influence of the design of the stem and the type of fixation on the rate of revision and immediate postoperative mortality, focusing on the age and sex of the patients.
A total of 333,144 patients with primary osteoarthritis (OA) of the hip who underwent elective THA between November 2012 and September 2022, using uncemented acetabular components without reconstruction shells, from the German arthroplasty registry were included in the study. The revision rates three years postoperatively for four types of stem (uncemented, uncemented with collar, uncemented short, and cemented) were compared within four age groups: < 60 years (Young), between 61 and 70 years (Mid-I), between 71 and 80 years (Mid-II), and aged > 80 years (Old). A noninferiority analysis was performed on the most frequently used designs of stem.
The design of the stem was found to have no significant influence on the rate of revision for either sex in the Young group. Uncemented collared stems had a significantly lower rate of revision compared with the other types of stem for females in the Mid-I group. There was a significantly higher rate of revision for uncemented stems in females in the Mid-II group compared with all other types of stem, while in males the rate for uncemented stems was only significantly higher than the rate for cemented stems. Cemented stems had a significantly lower revision rate compared with uncemented and short stems for both sexes in the Old cohort, as did females with collared stems. The rate of immediate postoperative mortality was similar for all types of stem in the Old age group, as were the American Society of Anesthesiologists grades.
In patients aged > 80 years, uncemented and short stems had significantly higher revision rates compared with cemented and collared stems, especially in females. The design of the stem and type of fixation have to be analyzed in more detail than only considering cemented and uncemented fixation, in order to further improve the success of THA.
The ecosystem services approach to resource management considers all services provided by ecosystems to all sections of the community. As such, it could be used to assess sustainability of human ...development and equity in resource use. To facilitate the approach, tools are required at the level of detail at which policy and management decisions are made. We have developed spatially explicit models of indicators of important ecosystem services in New Zealand: regulation of climate, control of soil erosion, regulation of water flow (quantity), provision of clean water (quality), provision of food and fibre, and provision of natural habitat. The models were developed using lookup tables from process-based models to allow rapid evaluation of land-use scenarios. We demonstrate the application of the models to assess ecosystem services in a simulation of hill-country afforestation in the Manawatu catchment, which has recently seen increasing soil erosion in the hills leading to sedimentation of waterways. Each ecosystem service was assessed by calculating the change in the indicator relative to two extremes. The ecosystem services with the largest relative changes were control of soil erosion, carbon sequestration, and provision of wood.
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► Spatial models of ecosystem service indicators were developed for New Zealand. ► Models are applicable using look-up tables from climate, soil, and land-use maps. ► Ecosystem services were quantified relative to indicator extremes. ► Models were tested in a scenario of afforestation on erosion-prone land.
•We measured the CO2 and C balances of an intensively managed pasture in New Zealand.•Averaged over 4 years, the site was a sink for both CO2 (165gCm−2y−1), and total C (61gCm−2y−1).•Climatic ...conditions and farm management both had large impacts on CO2 and total C budgets.•Global data compilation revealed C sequestration generally increased with increasing NEP.
We estimated the net ecosystem carbon (C) balance (NECB) of a temperate pasture in the North Island of New Zealand for four years (2008–2011). The pasture was intensively managed with addition of fertiliser and year-round rotational grazing by dairy cows. Climatic conditions and management practices had a large impact on CO2 exchange, with a severe drought in one year and cultivation in another both causing large short-term (∼3 months) net losses of CO2–C (100–200gCm−2). However, CO2 was regained later in both of these years so that on annual timescales, the site was a CO2 sink or CO2 neutral. Management practices such as effluent application and harvesting silage also influenced non-CO2–C fluxes, and had a large impact on annual NECB. Despite these major environmental or management perturbations, both NEP and NECB were relatively constant on annual timescales. It is likely that this apparent resilience of the CO2 and C balance to perturbations was at least partly attributable to the relatively warm temperatures, also in winter, providing good growing conditions year-round (in the absence of major perturbations such as moisture stress). In several instances, the farmer’s decisions aimed at maintaining a constant milk yield between years also appeared to contribute to a relatively stable C balance.
Averaged over the full four-year study period, the site was a net sink for both CO2 (NEP=165±51gCm−2y−1), and total C (NECB=61±53gCm−2y−1) after non-CO2–C fluxes were accounted for. Annual NEP and NECB values were similar to results collated from other managed temperate grasslands on mineral soils globally, for which average NEP and NECB were 188±44gCm−2y−1 and 44±33gCm−2y−1, respectively. In the global dataset, we noted a general trend for increased C sequestration with increasing NEP, suggesting that it may be possible to meet the dual goal of increased pasture production (thus milk, meat and fiber production) and increasing soil C storage in managed temperate grasslands. Identification of management practices that increase C storage while maintaining or enhancing pasture production requires more standardised reporting between NECB studies, and experiments involving side-by-side comparison of treatment and control plots.
The temperature dependence of C3 photosynthesis is known to vary with growth environment and with species. In an attempt to quantify this variability, a commonly used biochemically based ...photosynthesis model was parameterized from 19 gas exchange studies on tree and crop species. The parameter values obtained described the shape and amplitude of the temperature responses of the maximum rate of Rubisco activity (Vcmax) and the potential rate of electron transport (Jmax). Original data sets were used for this review, as it is shown that derived values of Vcmax and its temperature response depend strongly on assumptions made in derivation. Values of Jmax and Vcmax at 25 °C varied considerably among species but were strongly correlated, with an average Jmax : Vcmax ratio of 1·67. Two species grown in cold climates, however, had lower ratios. In all studies, the Jmax : Vcmax ratio declined strongly with measurement temperature. The relative temperature responses of Jmax and Vcmax were relatively constant among tree species. Activation energies averaged 50 kJ mol−1 for Jmax and 65 kJ mol−1 for Vcmax, and for most species temperature optima averaged 33 °C for Jmax and 40 °C for Vcmax. However, the cold climate tree species had low temperature optima for both Jmax(19 °C) and Vcmax (29 °C), suggesting acclimation of both processes to growth temperature. Crop species had somewhat different temperature responses, with higher activation energies for both Jmax and Vcmax, implying narrower peaks in the temperature response for these species. The results thus suggest that both growth environment and plant type can influence the photosynthetic response to temperature. Based on these results, several suggestions are made to improve modelling of temperature responses.
There is a need for further studies to compare the decomposition of biochar to that of the original feedstock and determine how these amendments affect the cycling of native organic matter (NOM) of ...different soils to improve our understanding of the resulting net C sequestration potential. A 510‐days incubation experiment was conducted (i) to investigate the evolution of CO2 from soils amended with either fresh corn stover (CS) or with biochars produced from fresh CS at either 350 (CS‐350) or 550 °C (CS‐550), and (ii) to evaluate the priming effect of these amendments on NOM decomposition. Two soil types were studied: an Alfisol and an Andisol, with organic C contents of 4% and 10%, respectively. Except for the controls (with no C addition), all treatments received 7.18 t C ha−1. We measured C efflux in short‐term intervals and its isotopic signature to distinguish between C evolved from C4 amendments and C3‐dominated NOM. Emission rates were then integrated for the whole time period to cover total emissions. Total CO2‐C evolved from the original C in fresh CS, CS‐350 and CS‐550 was greater in the Andisol (78%, 13% and 14%) than in the Alfisol (66%, 8% and 7%). For both soils, (i) no significant differences (P > 0.05) were observed in the rate of CO2 evolution between controls and biochar treatments; and (ii) total accumulated CO2 evolved from the uncharred amendment was significantly higher (P < 0.05) than that from the other treatments. In the Alfisol, a significant (P < 0.05) net positive priming effect on NOM decomposition was observed when amended with fresh CS, while the opposite was detected in biochar treatments. In the Andisol, no significant (P > 0.05) net priming effect was observed. A C balance indicated that the C lost from both biochar production and decomposition ‘broke even’ with that lost from fresh residue decomposition after <35 weeks. The ‘break‐even’ point was reached earlier in the Andisol, in which the fresh CS mineralizes faster. These results provided experimental evidence for the potential of biochar to sequester C and avoid CO2 emissions from original feedstock while protecting native soil organic matter.
We investigated the effect of UV radiation on photo-oxidation and microbial facilitation in humus and 3 litter types (pine, mānuka, and grass). We collected litter material as naturally senesced or ...fresh material, to determine whether senescence stage influenced the response to UV radiation. Further, the materials were either air dried or oven dried to assess whether drying temperature also altered the effect of UV radiation on photo-oxidation and microbial facilitation in these litters. Each sample was exposed continuously for 59 days at one of five levels of UV radiation using fluorescent lamps, with the higher levels of exposure being equivalent to mid-day summer values. The samples were then subsequently weighed to assess the extent of any photo-oxidation. The materials were then inoculated with microbial extracts and incubated in darkness for 35 days (25 °C) to determine if prior UV exposure induced microbial facilitation. However, despite the intensity of continuous UV exposure, we found neither photo-oxidation nor microbial facilitation in any of our litters. Neither leaf senescence stage nor drying temperature affected the response of the materials to UV, and all were equally non-responsive. Unexpectedly, in the pine and mānuka samples, higher UV exposure was even correlated with a slight, but consistent and statistically significant weight gain during UV incubation. There was also a slight decrease of subsequent CO2 production during microbial incubations in the pine and mānuka litters, which would indicate that these materials had become less biodegradable with increased exposure to UV radiation. These results are the opposite of those observed in most field studies, and we have been unable to find any explanation for these unexpected patterns.
•There was no photo-oxidation in any of the four materials investigated.•Nor was microbial facilitation found, although some indication of inhibition.•No effect of drying temperature or senescent stage on UV response.•Patterns opposite to most field studies, cause unknown.
The world's soils contain about 1500 Gt of organic carbon to a depth of 1m and a further 900 Gt from 1-2m. A change of total soil organic carbon by just 10% would thus be equivalent to all the ...anthropogenic CO2 emitted over 30 years. Warming is likely to increase both the rate of decomposition and net primary production (NPP), with a fraction of NPP forming new organic carbon. Evidence from various sources can be used to assess whether NPP or the rate of decomposition has the greater temperature sensitivity, and, hence, whether warming is likely to lead to an increase or decrease in soil organic carbon. Evidence is reviewed from laboratory-based incubations, field measurements of organic carbon storage, carbon isotope ratios and soil respiration with either naturally varying temperatures or after experimentally increasing soil temperatures. Estimates of terrestrial carbon stored at the Last Glacial Maximum are also reviewed. The review concludes that the temperature dependence of organic matter decomposition can be best described as: d(T) = exp3.36 (T - 40)/(T + 31.79) where d(T) is the normalised decomposition rate at temperature T (in °C). In this equation, decomposition rate is normalised to '1' at 40 °C. The review concludes by simulating the likely changes in soil organic carbon with warming. In summary, it appears likely that warming will have the effect of reducing soil organic carbon by stimulating decomposition rates more than NPP. However, increasing CO2 is likely to simultaneously have the effect of increasing soil organic carbon through increases in NPP. Any changes are also likely to be very slow. The net effect of changes in soil organic carbon on atmospheric CO2 loading over the next decades to centuries is, therefore, likely to be small.
Purpose
Misconceptions regarding activity and toxicity of therapeutic interventions are common among cancer patients. There is little knowledge about the factors that contribute to a more realistic ...perception by patients.
Methods
This pilot study was designed as a prospective questionnaire survey and included 101 therapy-naïve patients treated at the Division of Oncology, Medical University of Vienna. After obtaining written informed consent, patients’ expectations about treatment aims, side effects and the satisfaction with their oncologic consultation were interrogated before the first treatment cycle by questionnaires.
Results
Of 101 patients, 53 (53%) were female and 67/101 (66%) were treated with curative attempt in an adjuvant or neo-adjuvant setting. The most common diagnoses were lung cancer (31%) and breast cancer (30%). Although 92% of patients were satisfied with the information given by their oncologist, palliative patients were more likely to declare that not everything was explained in an intelligible manner (
p
= 0.01). Patients with a first language other than German stated more often that their physician did not listen carefully enough (
p
= 0.02). Of 30 patients, 26 (87%) receiving chemotherapy with palliative intent believed that their disease was curable. Concerning adverse events, female patients anticipated more frequently hair loss (
p
= 0.003) and changes in taste (
p
= 0.001) compared to men. Patients under curative treatment were more likely to expect weight loss (
p
= 0.02) and lack of appetite (
p
= 0.01) compared to patients with palliative treatment intent.
Conclusion
In conclusion, cancer patients were satisfied with the patient-doctor communication. This prospective study aggregated patients’ concerns on side effects and the perception of therapeutic goals in therapy-naïve patients. Of note, the majority of patients treated in the palliative setting expected their treatment to cure the disease.
Abstract
How strong correlations and topology interplay is a topic of great current interest. In this perspective paper, we focus on correlation-driven gapless phases. We take the time-reversal ...symmetric Weyl semimetal as an example because it is expected to have clear (albeit nonquantized) topological signatures in the Hall response and because the first strongly correlated representative, the noncentrosymmetric Weyl–Kondo semimetal Ce
3
Bi
4
Pd
3
, has recently been discovered. We summarize its key characteristics and use them to construct a prototype Weyl–Kondo semimetal temperature-magnetic field phase diagram. This allows for a substantiated assessment of other Weyl–Kondo semimetal candidate materials. We also put forward scaling plots of the intrinsic Berry-curvature-induced Hall response vs the inverse Weyl velocity—a measure of correlation strength, and vs the inverse charge carrier concentration—a measure of the proximity of Weyl nodes to the Fermi level. They suggest that the topological Hall response is maximized by strong correlations and small carrier concentrations. We hope that our work will guide the search for new Weyl–Kondo semimetals and correlated topological semimetals in general, and also trigger new theoretical work.
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