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Peat formation is the key process responsible for carbon sequestration in peatlands. In rich fens, peat is formed by brown mosses and belowground biomass of vascular plants. However, the impact of ecohydrological settings on the contribution of mosses and belowground biomass to peat formation remains an open question. We established seven transects in well-preserved fens in NE Poland along an ecohydrological gradient from mesotrophic sedge-moss communities with stable water levels, to more eutrophic tall sedge communities with higher water level fluctuations. In each transect, we measured the production of brown mosses (using the plug method), aboveground vascular plant biomass (one year after cutting) and belowground biomass (using ingrowth cores). Decomposition rates of all biomass fractions were assessed using litter bags. The first-year surplus of potentially peat-forming fractions, i.e., mosses and belowground biomass, decreased with increasing water level fluctuations and along a vegetation gradient from sedge-moss to tall sedge communities. Moss production was highest in the sedge-moss fen with a stable water level at the ground surface. We did not detect any difference in belowground biomass production across the gradient but found it to be consistently higher in the upper 0-5 cm than in the deeper layers. The decomposition rate also showed no response to the gradient, but differed between biomass types, with aboveground biomass of vascular plants decomposing 2.5 times faster than belowground biomass and mosses. Pattern of peat formation potential along the ecohydrological gradient in rich fen was strongly driven by brown moss production. Sedge-moss fens with a stable water level at the ground surface have the highest peat formation capacity compared to other vegetation types. In the part of the gradient that is poorer in nutrients, vascular plants invest in belowground production, and mosses dominate the aboveground layer., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The Tibetan Plateau's Kobresia pastures store 2.5% of the world's soil organic carbon (SOC). Climate change and overgrazing render their topsoils vulnerable to degradation, with SOC stocks declining by 42% and nitrogen (N) by 33% at severely degraded sites. We resolved these losses into erosion accounting for two-thirds, and decreased carbon (C) input and increased SOC mineralization accounting for the other third, and confirmed these results by comparison with a meta-analysis of 594 observations. The microbial community responded to the degradation through altered taxonomic composition and enzymatic activities. Hydrolytic enzyme activities were reduced, while degradation of the remaining recalcitrant soil organic matter by oxidative enzymes was accelerated, demonstrating a severe shift in microbial functioning. This may irreversibly alter the world´s largest alpine pastoral ecosystem by diminishing its C sink function and nutrient cycling dynamics, negatively impacting local food security, regional water quality and climate., (© 2022. The Author(s).)

Ground- and surface-water-fed peatlands (i.e., fens) of temperate Europe face high anthropogenic nutrient loads from atmospheric deposition, agricultural catchment areas, and from peat decomposition, if drained. As a result, nitrogen loads may exceed a fen's natural nutrient removal capacity, leading to increased eutrophication of adjacent water bodies. Therefore, it is important to address possible means to decrease a fen's nutrient load, including nutrient uptake by fen plants. To assess how much fen plants can contribute to nutrient removal by uptake, nutrient stocks of above- and below-ground biomass need to be quantified. Therefore, we investigated nitrogen, phosphorous, and potassium uptake capacities of sedges (Carex species), which are common dominants in fen plant communities. We grew specimens of five Carex species with varying preferences in nutrient availability under controlled, different nutrient levels. We show that Carex above-ground biomass harvest can remove up to one third of a system's total nitrogen even at high loads of about 40 g nitrogen m -2 . Species-specific differences in biomass production, rather than preferences in nutrient availability under natural conditions, were drivers of standing nutrient stocks: Highly productive species, i.e., C. acutiformis and C. rostrata, had highest nutrient standing stocks across all nutrient levels. Amounts of nutrients stored in shoots increased almost linearly with increasing nutrient levels, whereas below-ground nutrient stocks species-specifically increased, saturated, or decreased, with increasing nutrient levels. As a rough estimate, depending on the species, 6-16 cycles of annual above-ground harvest would suffice to decrease nitrogen concentrations from the highest to the lowest level used in this study. Overall, our results indicate that Carex biomass harvest can be an efficient means to counteract anthropogenic nitrogen eutrophication in fens., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Many of the world's peatlands have been affected by water table drawdown and subsequent loss of organic matter. Rewetting has been proposed as a measure to restore peatland functioning and to halt carbon loss, but its effectiveness is subject to debate. An important prerequisite for peatland recovery is a return of typical microbial communities, which drive key processes. To evaluate the effect of rewetting, we investigated 13 fen peatland areas across a wide (>1500 km) longitudinal gradient in Europe, in which we compared microbial communities between drained, undrained, and rewetted sites. There was a clear difference in microbial communities between drained and undrained fens, regardless of location. Community recovery upon rewetting was substantial in the majority of sites, and predictive functional profiling suggested a concomitant recovery of biogeochemical peatland functioning. However, communities in rewetted sites were only similar to those of undrained sites when soil organic matter quality (as expressed by cellulose fractions) and quantity were still sufficiently high. We estimate that a minimum organic matter content of ca. 70% is required to enable microbial recovery. We conclude that peatland recovery after rewetting is conditional on the level of drainage-induced degradation: severely altered physicochemical peat properties may preclude complete recovery for decades.

With 450,000 km 2 Kobresia (syn. Carex) pygmaea dominated pastures in the eastern Tibetan highlands are the world's largest pastoral alpine ecosystem forming a durable turf cover at 3000-6000 m a.s.l. Kobresia's resilience and competitiveness is based on dwarf habit, predominantly below-ground allocation of photo assimilates, mixture of seed production and clonal growth, and high genetic diversity. Kobresia growth is co-limited by livestock-mediated nutrient withdrawal and, in the drier parts of the plateau, low rainfall during the short and cold growing season. Overstocking has caused pasture degradation and soil deterioration over most parts of the Tibetan highlands and is the basis for this man-made ecosystem. Natural autocyclic processes of turf destruction and soil erosion are initiated through polygonal turf cover cracking, and accelerated by soil-dwelling endemic small mammals in the absence of predators. The major consequences of vegetation cover deterioration include the release of large amounts of C, earlier diurnal formation of clouds, and decreased surface temperatures. These effects decrease the recovery potential of Kobresia pastures and make them more vulnerable to anthropogenic pressure and climate change. Traditional migratory rangeland management was sustainable over millennia, and possibly still offers the best strategy to conserve and possibly increase C stocks in the Kobresia turf., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

The Tibetan highlands host the largest alpine grassland ecosystems worldwide, bearing soils that store substantial stocks of carbon (C) that are very sensitive to land use changes. This study focuses on the cycling of photoassimilated C within a Kobresia pygmaea pasture, the dominating ecosystems on the Tibetan highlands. We investigated short-term effects of grazing cessation and the role of the characteristic Kobresia root turf on C fluxes and belowground C turnover. By combining eddy-covariance measurements with (13)CO₂ pulse labeling we applied a powerful new approach to measure absolute fluxes of assimilates within and between various pools of the plant-soil-atmosphere system. The roots and soil each store roughly 50% of the overall C in the system (76 Mg C ha(-1)), with only a minor contribution from shoots, which is also expressed in the root:shoot ratio of 90. During June and July the pasture acted as a weak C sink with a strong uptake of approximately 2 g C m(-2) d(-1) in the first half of July. The root turf was the main compartment for the turnover of photoassimilates, with a subset of highly dynamic roots (mean residence time 20 days), and plays a key role for the C cycling and C storage in this ecosystem. The short-term grazing cessation only affected aboveground biomass but not ecosystem scale C exchange or assimilate allocation into roots and soil., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Purpose: The objective of our study was to evaluate whether preoperative ultrasound-guided marking of calcium deposits has a positive effect on the efficiency and speed of localization of calcium deposits during surgery, and whether this technique is a factor that increases the probability of good clinical results., Methods: Twenty-four patients who required surgery for calcific tendinitis in the years 2001 and 2002 were divided into 2 groups of 12 patients by week. Before undergoing surgery, those in group 1 (weeks 1, 3, 5, etc.) were given a standard ultrasound examination, along with preoperative ultrasound-guided marking (pre-USM) of calcium deposits, whereas group 2 (weeks 2, 4, 6, etc.) received the standard ultrasound examination without pre-USM. In both groups, arthroscopic removal of calcium deposits was carried out and the postoperative treatment plan was identical. The clinical result was evaluated by the Constant-Murley score., Results: At the 6-week and 2-year follow-up visits, the clinical result was significantly better (P < .05) in the pre-USM group than in the unmarked group (Constant score of 76 v 70 points and 80 v 74 points, respectively). After 12 weeks, the clinical outcomes of both groups showed an approaching significance, with better results seen in the pre-USM group (79 v 74 points; P = .052). The time required for intraoperative localization of calcium deposits was 16 versus 22 minutes. The difference showed an approaching significance (P = .057). Removal of calcium was possible in 12 versus 10 cases; complete removal was possible in 8 versus 6 cases, respectively. However, none of these variables had a statistically significant influence on our results., Conclusions: Preoperative ultrasound-guided marking of calcific deposits is a procedure that statistically significantly improves the clinical results of arthroscopic surgery as seen at 6 weeks and 2 years; statistical significance of .052 was approached only at 12 weeks, as we have shown here for calcifying tendinitis of the shoulder joint., Level of Evidence: Level III, development of diagnostic criteria with nonconsecutive patients.

Objectives: The objective of the present study was to assess the validity of ultrasound diagnosis of shoulder disorders in relation to examiner experience., Methods: A total of 239 patients referred to us for shoulder arthroscopy from October 2001 to June 2004 were prospectively studied by ultrasound. The following ultrasound diagnoses were evaluated: total and partial rotator cuff tears, calcific tendinitis, biceps tendon injuries and subacromial bursitis. Examiner A established the ultrasound diagnoses and examiner B performed the surgery during week A, whereas examiner B did the examinations and examiner A operated in week B. The surgeon was blinded to the ultrasound results. Examiner A conducts ultrasound training seminars for DEGUM, the German Society of Ultrasound in Medicine, and has performed over 10,000 ultrasound examinations, with an average of roughly 150 examinations per year. Examiner B completed his ultrasound training some years ago and has performed roughly 1500 examinations (50 per year). The results were analysed in a time-independent and blinded manner by the co-author (H), who neither operated nor examined the patients., Results: Ultrasound correctly identified 103 of 104 complete rotator cuff tears (sensitivity: 0.99--specificity: 0.99--accuracy: 98.7%). Both examiners achieved comparable results. Moreover, 41 of 52 partial rotator cuff tears were detected preoperatively (sensitivity: 0.79--specificity: 0.91--accuracy: 88.7%). Examiner A achieved a sensitivity of 0.92, a specificity of 0.95, and an accuracy of 94.7%. The corresponding rates for examiner B were: sensitivity 0.68, specificity 0.86, and accuracy 81.3%. 16 of 23 injuries of the long biceps tendon were identified correctly (4 of 8 dislocations and 12 of 15 tears: sensitivity 0.53; specificity 0.9; accuracy 95.3%). Examiner A achieved: sensitivity 0.58; specificity 0.99; accuracy 91.7% compared to examiner B: sensitivity 0.33; specificity 0.97; accuracy 95.3%. Both examiners correctly identified all 32 cases of calcific tendinitis (sensitivity 1.0; specificity 0.98; accuracy 98.3 % examiner A: 1.0--1.0--100% examiner B: 1.0--0.96--96.2%). 22 of 28 cases of subacromial bursitis were correctly diagnosed (sensitivity 0.79; specificity 0.98; accuracy 95.8% examiner A: 0.92--0.99--98.5% examiner B: 0.69--0.97--92.5%)., Conclusions: Preoperative ultrasound examination of the shoulder permits a reliable diagnosis of complete rotator cuff tears and calcium deposits (calcific tendinitis). The method is less sensitive but sufficiently reliable for the diagnosis of partial rotator cuff tears and pathology of the long biceps tendon. Examiner experience plays an important role in these special cases. Permanent continuous training in the field of ultrasound diagnosis is a prerequisite for sufficient reliability of ultrasound diagnosis of shoulder disorders.

Different factors for periarticular calcification following total hip replacement were analysed in a follow up study. The extent and location was evaluated in accordance to classification of Arcq (1973) with a grid stencil. In 68.5% of 111 THR's calcification of different degrees were to obtain. Early calcifications were to find 2 weeks and in completed form 6 month after the operation in x-ray. The most frequent location was around the Trochanter major. In dependence of operation's term male patients are more affected than females. Age, diagnosis, former operations, typ of prosthesis, secretion of wound and postoperative complications seem to have no influence on periarticular calcifications.