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To evaluate how increased anthropogenic nutrient inputs alter carbon cycling in grasslands, we conducted a litter decomposition study across 20 temperate grasslands on three continents within the Nutrient Network, a globally distributed nutrient enrichment experiment We determined the effects of addition of experimental nitrogen (N), phosphorus (P) and potassium plus micronutrient (Kμ) on decomposition of a common tree leaf litter in a long-term study (maximum of 7 years; exact deployment period varied across sites). The use of higher order decomposition models allowed us to distinguish between the effects of nutrients on early- versus late-stage decomposition. Across continents, the addition of N (but not other nutrients) accelerated early-stage decomposition and slowed late-stage decomposition, increasing the slowly decomposing fraction by 28% and the overall litter mean residence time by 58%. Synthesis. Using a novel, long-term cross-site experiment, we found widespread evidence that N enhances the early stages of above-ground plant litter decomposition across diverse and widespread temperate grassland sites but slows late-stage decomposition. These findings were corroborated by fitting the data to multiple decomposition models and have implications for N effects on soil organic matter formation. For example, following N enrichment, increased microbial processing of litter substrates early in decomposition could promote the production and transfer of low molecular weight compounds to soils and potentially enhance the stabilization of mineral-associated organic matter. By contrast, by slowing late-stage decomposition, N enrichment could promote particulate organic matter (POM) accumulation. Such hypotheses deserve further testing.

Spaceborne Global Navigation Satellite System (GNSS) receivers have become indispensable components of satellites, in particular for real-time navigation as part of the attitude and orbit control system and for precise orbit determination in support of highly accurate earth observation instruments. In cooperation with the project partners TU Dresden and the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Beyond Gravity (formerly RUAG Space) has developed a flexible GNSS receiver platform targeting NewSpace applications but leveraging the performance of the current gold standards with respect to spaceborne GNSS-receiver technology. A novel radiation test environment was introduced, and selected components were radiation tested to ensure a consistent reliability.

Background and aims: The amount of nitrogen (N) derived from symbiotic N₂ fixation by legumes in grasslands might be affected by anthropogenic N and phosphorus (P) inputs, but the underlying mechanisms are not known. Methods: We evaluated symbiotic N₂ fixation in 17 natural and semi-natural grasslands on four continents that are subjected to the same full-factorial N and P addition experiment, using the ¹⁵N natural abundance method. Results: N as well as combined N and P (NP) addition reduced aboveground legume biomass by 65% and 45%, respectively, compared to the control, whereas P addition had no significant impact. Addition of N and/or P had no significant effect on the symbiotic N₂ fixation per unit legume biomass. In consequence, the amount of N fixed annually per grassland area was less than half in the N addition treatments compared to control and P addition, irrespective of whether the dominant legumes were annuals or perennials. Conclusion: Our results reveal that N addition mainly impacts symbiotic N₂ fixation via reduced biomass of legumes rather than changes in N₂ fixation per unit legume biomass. The results show that soil N enrichment by anthropogenic activities significantly reduces N₂ fixation in grasslands, and these effects cannot be reversed by additional P amendment.

In the version of this Article originally published, there were unit conversion errors in the dataset when calculating specific leaf area (SLA) values at 10 of the 27 sites; errors were made when converting SLA from cm 2 g –1 to mm 2 g –1 and from mm 2 mg –1 to mm 2 g –1. This resulted in two incorrect data points: Phleum pratense in plot 27 at the Frue.ch site (SLA >300,000 mm 2 g –1) and Poa secunda in plot 31 at the shps.us site (SLA >60 mm 2 g –1). These two values were changed to ‘NA’ in the dataset, and therefore some reported estimates were changed, resulting in changes to the data points in Fig. 2a, the top bar of Fig. 3 and several values in the text.

Background and rationale Although general trauma care systems and their effects on mortality reduction have been studied, little is known of the current state of musculoskeletal trauma delivery globally, particularly in low-income (LI) and low middle-income (LMI) countries. The goal of this study is to assess and describe the development and availability of musculoskeletal trauma care delivery worldwide. Materials & methods A questionnaire was developed to evaluate different characteristics of general and musculoskeletal trauma care systems, including general aspects of systems, education, access to care and pre- and posthospital care. Surgical leaders involved with musculoskeletal trauma care were contacted to participate in the survey. Results Of the 170 surveys sent, 95 were returned for use for the study. Nearly 30 percent of surgeons reported a formalized and coordinated trauma system in their countries. Estimates for the number of surgeons providing musculoskeletal trauma per one million inhabitants varied from 2.6 in LI countries to 58.8 in high-income countries. Worldwide, 15% of those caring for musculoskeletal trauma are fellowship trained. The survey results indicate a lack of implemented musculoskeletal trauma care guidelines across countries, with even high-income countries reporting less than 50% availability in most categories. Seventy-nine percent of the populations from LI countries were estimated to have no form of health care insurance. Formalized emergency medical services were reportedly available in only 33% and 50% of LI and LMI countries, respectively. Surgeons from LI and LMI countries responded that improvements in the availability of equipment (100%), number and locations of trauma-designated hospitals (90%), and physician training programs (88%) were necessary in their countries. The survey also revealed a general lack of resources for postoperative and rehabilitation care, irrespective of the country's income level. Conclusion This study addresses the current state of musculoskeletal trauma care delivery worldwide. These results indicate a greater need for trauma system development and support, from prehospital through posthospital care. Optimization of these systems can lead to better outcomes for patients after trauma. This study represents a critical first step toward better understanding the state of musculoskeletal trauma care in countries with different levels of resources, developing strategies to address deficiencies, and forming regional and international collaborations to develop musculoskeletal trauma care guidelines.