Towards a methodical framework for comprehensively assessing forest multifunctionality

Funded by Deutsche Forschungsgemeinschaft. Grant Number: DFG FOR 891/1-3 National Natural Science Foundation of China. Grant Numbers: 30710103907, 30930005, 31170457, 31210103910 Swiss National Science Foundation (SNSF) Sino-German Centre for Research Promotion in Beijing. Grant Number: GZ 986Peer reviewedPublisher PD

Assessing quality of care for the dying from the bereaved relatives’ perspective: using pre-testing survey methods across seven countries to develop an international outcome measure

Background: The provision of care for dying cancer patients varies on a global basis. In order to improve care, we need to be able to evaluate the current level of care. One method of assessment is to use the views from the bereaved relatives. Aim: The aim of this study is to translate and pre-test the ‘Care Of the Dying Evaluation’ (CODETM) questionnaire across seven participating countries prior to conducting an evaluation of current quality of care. Design: The three stages were as follows: (1) translation of CODE in keeping with standardised international principles; (2) pre-testing using patient and public involvement and cognitive interviews with bereaved relatives; and (3) utilising a modified nominal group technique to establish a common, core international version of CODE. Setting/participants: Hospital settings: for each country, at least five patient and public involvement representatives, selected by purposive sampling, fed back on CODETM questionnaire; and at least five bereaved relatives to cancer patients undertook cognitive interviews. Feedback was collated and categorised into themes relating to clarity, recall, sensitivity and response options. Structured consensus meeting held to determine content of international CODE (i-CODE) questionnaire. Results: In total, 48 patient and public involvement representatives and 35 bereaved relatives contributed to the pre-testing stages. No specific question item was recommended for exclusion from CODETM. Revisions to the demographic section were needed to be culturally appropriate. Conclusion: Patient and public involvement and bereaved relatives’ perceptions helped enhance the face and content validity of i-CODE. A common, core international questionnaire is now developed with key questions relating to quality of care for the dying

Toward a methodical framework for comprehensively assessing forest multifunctionality

Biodiversity-ecosystem functioning (BEF) research has extended its scope from communities that are short-lived or reshape their structure annually to structurally complex forest ecosystems. The establishment of tree diversity experiments poses specific methodological challenges for assessing the multiple functions provided by forest ecosystems. In particular, methodological inconsistencies and nonstandardized protocols impede the analysis of multifunctionality within, and comparability across the increasing number of tree diversity experiments. By providing an overview on key methods currently applied in one of the largest forest biodiversity experiments, we show how methods differing in scale and simplicity can be combined to retrieve consistent data allowing novel insights into forest ecosystem functioning. Furthermore, we discuss and develop recommendations for the integration and transferability of diverse methodical approaches to present and future forest biodiversity experiments. We identified four principles that should guide basic decisions concerning method selection for tree diversity experiments and forest BEF research: (1) method selection should be directed toward maximizing data density to increase the number of measured variables in each plot. (2) Methods should cover all relevant scales of the experiment to consider scale dependencies of biodiversity effects. (3) The same variable should be evaluated with the same method across space and time for adequate larger-scale and longer-time data analysis and to reduce errors due to changing measurement protocols. (4) Standardized, practical and rapid methods for assessing biodiversity and ecosystem functions should be promoted to increase comparability among forest BEF experiments. We demonstrate that currently available methods provide us with a sophisticated toolbox to improve a synergistic understanding of forest multifunctionality. However, these methods require further adjustment to the specific requirements of structurally complex and long-lived forest ecosystems. By applying methods connecting relevant scales, trophic levels, and above? and belowground ecosystem compartments, knowledge gain from large tree diversity experiments can be optimized

Does species richness of subtropical tree leaf litter affect decomposition, nutrient release, transfer and subsequent uptake by plants?

During leaf litter decomposition, nutrients are released, can be transferred among different litter species, are metabolized by soil organisms and are taken up by plants again. However, it remains unclear to which extent leaf litter species richness affects these processes of nutrient cycling, and whether effects on one of those processes propagate to the subsequent one. We established a common garden decomposition experiment in a Chinese subtropical secondary forest, to trace two essential nutrients during decomposition and their uptake by plants along a litter species diversity gradient. Unlabelled, and 15N and Li (as surrogate for K) labelled leaves of three native tree species were used to create replicated 1-, 2- and 3-species mixtures, each with one species labelled per mixture. Litter mixtures were placed in mesocosms with one growing herbaceous phytometer plant. Over six months, litter and phytometer plants of each mixture were sampled at four points in time and the different process steps of nutrient dynamics were determined. Our results showed species and nutrient specific decomposition dynamics, which propagated through the processes of mass loss, nutrient release and transfer among species, and nutrient uptake dynamics of phytometer plants. However, we found no litter species diversity effects along the different litter decomposition processes. Rather specific diversity effects occurred in few cases at different points in time for mass loss, Li release and transfer dynamics. These effects were not caused by nutrient transfer from labelled to unlabelled litter, suggesting that species identity effects on decomposer dynamics may outweigh effects of nutrient transfer among litter species in mixtures. Further, the observed litter species diversity effects did not affect the 15N uptake of phytometer plants. Hence, the influence of species diversity on nutrient cycling and plant available nutrient stocks is mainly determined by the amount and variety of chemical compounds that different species exhibit and release to the soil

Leaf litter diversity positively affects the decomposition of plant polyphenols

ackground and Aims Leaf litter decomposition is closely linked to nutrient cycling and driven by environmental conditions, species-specific leaf chemistry, and here in particular by polyphenols composition. However, not much attention has been paid on the decomposition of polyphenols themselves. We hypothesized that phenolics and tannin decomposition rates are species-specific and positively affected by litter species richness. Methods Leaf litter of three Chinese tree species was exposed to field decomposition conditions, aggregated in mixtures of different species richness (1-, 2-, 3-species mixtures). We sampled litter five times over the course of 171 days, calculated species-specific total phenolics and total protein precipitable tannin decomposition rates, assessed changes in polyphenol composition using HPLC, and tentatively identified compounds by LC-ESI-MS/MS. Results Leaf litter richness effects on phenolics and tannin decomposition rates were positive, except for Sapindus-specific tannins, and differed between leaf litter species. Decomposition duration changed polyphenol compositions, and significantly interacted with leaf litter species richness with increasing effects of litter richness with time. Conclusions Litter diversity effects on polyphenol decomposition are crucial for whole leaf litter decomposition. The contrasting dependencies of phenolics and tannin decomposition rates on leaf litter richness may provide explanations for equivocal results in leaf litter mixture experiments

Leaf litter diversity alters microbial activity, microbial abundances, and nutrient cycling in a subtropical forest ecosystem

Human activities affect both tree species composition and diversity in forested ecosystems. This in turn alters the species diversity of plant litter and litter quality, which may have cascading effects on soil microbial communities and their functions for decomposition and nutrient cycling. We tested microbial responses to litter species diversity in a leaf litter decomposition experiment including monocultures, 2-, and 4-species mixtures in the subtropical climate zone of southeastern China. Soil microbial community composition was assessed by lipid analysis, and microbial functions were measured using extracellular enzyme activity and gross rates of nitrogen mineralization. We observed a positive relationship between litter species diversity and abundances of mycorrhizal fungi and actinomycetes. Alternatively, enzyme activities involved in carbon and phosphorus acquisition, and enzyme indices of relative carbon limitation, were higher only in the 4-species mixtures. This suggests that the minimum basal substrate level for enzyme production was reached, or that limitation was higher, at the highest diversity level only. Responses to litter diversity also changed over time, where phosphatase responses to litter diversity were strongest early in decomposition and the indices of carbon limitation relative to other nutrients showed stronger responses later in decomposition. Enzyme activities were related to lipid biomarker data and the mass of litter remaining at the third time point, but relationships between enzyme activity and the mass of litter remaining were not consistent across other time points. We conclude that litter species richness will likely only reduce microbial functions at key intervals of diversity loss while microbial growth is more sensitive to incremental diversity loss, with no clear relationships between them or to ecosystem functions. The observed litter diversity effects on soil microbial biomass and enzyme activity indicate interactions of aboveground and belowground communities, and together with environmental conditions they are important for maintaining ecosystem functions

Early life serum neurofilament dynamics predict neurodevelopmental outcome of preterm infants

Background and purpose To determine whether neurofilament light chain (NfL), a promising serum and cerebrospinal fluid (CSF) biomarker of neuroaxonal damage, predicts functional outcome in preterm infants with neonatal brain injury. Methods Our prospective observational study used a sensitive single-molecule array assay to measure serum and CSF NfL concentrations in preterm infants with moderate to severe peri/intraventricular hemorrhage (PIVH). We determined temporal serum and CSF NfL profiles from the initial diagnosis of PIVH until term-equivalent age and their association with clinical and neurodevelopmental outcome until 2 years of age assessed by Bayley Scales of Infant Development (3rd edition). We fitted univariate and multivariate logistic regression models to determine risk factors for poor motor and cognitive development. Results The study included 48 infants born at < 32 weeks of gestation. Median serum NfL (sNfL) at PIVH diagnosis was 251 pg/mL [interquartile range (IQR) 139–379], decreasing markedly until term-equivalent age to 15.7 pg/mL (IQR 11.1–33.5). CSF NfL was on average 113-fold higher (IQR 40–211) than corresponding sNfL values. Additional cerebral infarction (n = 25)-but not post-hemorrhagic hydrocephalus requiring external ventricular drainage (n = 29) nor any other impairment-was independently associated with sNfL. Multivariate logistic regression models identified sNfL as an independent predictor of poor motor outcome or death at 1 and 2 years. Conclusions Serum neurofilament light chain dynamics in the first weeks of life predict motor outcome in preterm infants with PIVH

Serum neurofilament as a predictor of disease worsening and brain and spinal cord atrophy in multiple sclerosis

See Giovannoni (doi:10.1093/brain/awy200) for a scientific commentary on this article. Biomarkers of tissue damage in multiple sclerosis are urgently needed. Barro et al. show that serum neurofilament light chain (NfL) levels are increased in patients versus healthy controls and reflect radiological and clinical disease activity and progression. High serum NfL is associated with greater subsequent brain and spinal cord atrophy

Toward a methodical framework for comprehensively assessing forest multifunctionality

Biodiversity-ecosystem functioning (BEF) research has extended its scope from communities that are short-lived or reshape their structure annually to structurally complex forest ecosystems. The establishment of tree diversity experiments poses specific methodological challenges for assessing the multiple functions provided by forest ecosystems. In particular, methodological inconsistencies and nonstandardized protocols impede the analysis of multifunctionality within, and comparability across the increasing number of tree diversity experiments. By providing an overview on key methods currently applied in one of the largest forest biodiversity experiments, we show how methods differing in scale and simplicity can be combined to retrieve consistent data allowing novel insights into forest ecosystem functioning. Furthermore, we discuss and develop recommendations for the integration and transferability of diverse methodical approaches to present and future forest biodiversity experiments. We identified four principles that should guide basic decisions concerning method selection for tree diversity experiments and forest BEF research: (1) method selection should be directed toward maximizing data density to increase the number of measured variables in each plot. (2) Methods should cover all relevant scales of the experiment to consider scale dependencies of biodiversity effects. (3) The same variable should be evaluated with the same method across space and time for adequate larger-scale and longer-time data analysis and to reduce errors due to changing measurement protocols. (4) Standardized, practical and rapid methods for assessing biodiversity and ecosystem functions should be promoted to increase comparability among forest BEF experiments. We demonstrate that currently available methods provide us with a sophisticated toolbox to improve a synergistic understanding of forest multifunctionality. However, these methods require further adjustment to the specific requirements of structurally complex and long-lived forest ecosystems. By applying methods connecting relevant scales, trophic levels, and above- and belowground ecosystem compartments, knowledge gain from large tree diversity experiments can be optimized

Data from: Tree species richness increases ecosystem carbon storage in subtropical forests

Forest ecosystems are an integral component of the global carbon cycle as they take up and release large amounts of C in short time (C flux) or accumulate it over longer time (C stock). However, there remains uncertainty about whether and in which direction C fluxes and in particular C stocks may differ between forests of high vs. low species richness. Based on a comprehensive dataset derived from field-based measurements, we tested the effect of species richness (3–20 tree species) and stand age (22–116 years) on six compartments of above- and belowground C stocks and four components of C fluxes in subtropical forests in south-east China. Across forest stands, total C stock was 149 ± 12 Mg ha-1 with richness explaining 28.5% and age explaining 29.4% of variation in this measure. Species-rich stands had higher C stocks and fluxes than stands with low richness; and, in addition, old stands had higher C stocks than young ones. Overall, for each additional tree species the total C stock increased by 6.4%. Our results provide comprehensive evidence for diversity-mediated above- and belowground C sequestration in species-rich subtropical forests in south-east China. Therefore, afforestation policies in this region and elsewhere should consider a change from the current focus on monocultures to multi-species plantations to increase C fixation and thus slow increasing atmospheric CO2 concentrations and global warming