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Most of the world’s mountain glaciers have been retreating for more than a century in response to climate change. Glacier retreat is evident on all continents, and the rate of retreat has accelerated during recent decades. Accurate, spatially explicit information on the position of glacier margins over time is useful for analyzing patterns of glacier retreat and measuring reductions in glacier surface area. This information is also essential for evaluating how mountain ecosystems are evolving due to climate warming and the attendant glacier retreat. Here, we present a non-comprehensive spatially explicit dataset showing multiple positions of glacier fronts since the Little Ice Age (LIA) maxima, including many data from the pre-satellite era. The dataset is based on multiple historical archival records including topographical maps; repeated photographs, paintings, and aerial or satellite images with a supplement of geochronology; and own field data. We provide ESRI shapefiles showing 728 past positions of 94 glacier fronts from all continents, except Antarctica, covering the period between the Little Ice Age maxima and the present. On average, the time series span the past 190 years. From 2 to 46 past positions per glacier are depicted (on average: 7.8).

AbstractThe bioenergy crops such as energycane, miscanthus, and sorghum are being genetically modified using state of the art synthetic biotechnology techniques to accumulate energy‐rich molecules such as triacylglycerides (TAGs) in their vegetative cells to enhance their utility for biofuel production. During the initial genetic developmental phase, many hundreds of transgenic phenotypes are produced. The efficiency of the production pipeline requires early and minimally destructive determination of oil content in individuals. Current screening methods require time‐intensive sample preparation and extraction with chemical solvents for each plant tissue. A rapid screen will also be needed for developing industrial extraction as these crops become available. In the present study, we have devised a proton relaxation nuclear magnetic resonance (1H‐NMR) method for single‐step, non‐invasive, and chemical‐free characterization of in‐situ lipids in untreated and pretreated lignocellulosic biomass. The systematic evaluation of NMR relaxation time distribution provided insight into the proton environment associated with the lipids in the biomass. It resolved two distinct lipid‐associated subpopulations of proton nuclei that characterize total in‐situ lipids into bound and free oil based on their “molecular tumbling” rate. The T1T2 correlation spectra also facilitated the resolution of the influence of various pretreatment procedures on the chemical composition of molecular and local 1H population in each sample. Furthermore, we show that hydrothermally pretreated biomass is suitable for direct NMR analysis unlike dilute acid and alkaline pretreated biomass which needs an additional step for neutralization.

Abstract Tropical mountain cloud forests (TMCF) harbour a high bryophyte (mosses and liverworts) biomass and diversity. Furthermore, the high air humidity makes these forests well suited for bryophyte‐associated nitrogen (N2) fixation by cyanobacteria, providing a potentially important source of N input to the ecosystem. However, few studies have assessed bryophyte‐associated N input in these ecosystems, and these have focused on epiphytic bryophytes, whereas abundant ground‐covering bryophytes have not been included. In this study, we quantified N2 fixation rates associated with bryophytes, focusing on ground‐covering mosses in a neotropical mountain cloud forest. Furthermore, we identified the effects of climate change (higher temperature 10 vs. 20° and lower bryophyte moisture level 50% vs. 100%) on N2 fixation across bryophyte species and groups (mosses and liverworts). Nitrogen fixation rates associated with ground‐covering moss species were up to 2 kg N ha−1 year−1, which is comparable to other N inputs (e.g. N deposition) in tropical cloud forests. Furthermore, changes in temperature showed little effect on N2 fixation, but low moisture levels significantly suppressed N2 fixation activity. We found low N2 fixation activity associated with the investigated liverworts. Our results demonstrate the importance of ground‐covering, moss‐associated N2 fixation as a N source in tropical cloud forests and suggest that predicted future declines in precipitation in these systems will reduce N inputs from bryophyte‐associated cyanobacteria. Read the free Plain Language Summary for this article on the Journal blog.

AbstractAimAgriculture is one of the greatest pressures on biodiversity. Regional studies have shown that the presence of natural habitat and landscape heterogeneity are beneficial for biodiversity in agriculture, but it remains unclear whether their importance varies geographically. Here, we use local biodiversity data to determine which local and landscape variables are most associated with biodiversity patterns and whether their association varies between tropical and non‐tropical regions.LocationGlobal terrestrial area in forest biomes.Major taxa studiedMore than 21,000 species of vertebrates, invertebrates, plants and other taxa.MethodsWe used generalized linear mixed‐effects models to analyse the relationships between either community total abundance or species richness (derived from the PREDICTS database) and a number of site‐level (predominant land use and land‐use intensity) and landscape‐level variables (distance to forest, the percentage of natural habitat in the surrounding landscape, landscape homogeneity, the number of land‐cover types in the landscape, and total fertilizer application). We compared the associations of these variables with biodiversity in tropical and non‐tropical regions.ResultsIn most cases, changes in biodiversity associated with landscape‐level variables were greater than those associated with local land use and land‐use intensity. Increased natural habitat availability was associated with the most consistent increases in biodiversity. Landscape homogeneity was also important but showed different directions of biodiversity change between regions. Associations with fertilizer application or the number of land‐cover types were generally weaker, although still of greater magnitude than for the local land‐use measures.Main conclusionsOur results highlight similarities and differences in the association of local‐ and landscape‐scale variables with local biodiversity in tropical and non‐tropical regions. Landscape natural habitat availability had a consistent positive association with biodiversity, highlighting the key role of landscape management in the maintenance of biodiversity in croplands. Landscape‐scale variables were almost always associated with greater changes in biodiversity than the local‐scale measures.

This article reports upon research on vegan transition, which I bring into dialogue with Sara Ahmed’s figure of the killjoy. Ahmed’s work on affect and the feminist killjoy is found to be apt for considering contemporary vegans and their transgression of normative scripts of happiness and commensality in a dominant meat and dairy consuming culture. The decentring of joy and happiness is also found to be integral to the critical deconstructive work of the vegan killjoy. Ahmed’s ideas further complement the frame of practice theory that I draw upon to understand the process of transition especially in the sense of opposing the meanings of dominant practices. Although food and veganism are not commented upon by Ahmed, the vegan subject constitutes, I argue, a potent further example of what she terms an “affect alien” who must willfully struggle against a dominant affective order and community. Drawing upon interviews with 40 vegans based in the UK, I illustrate examples of contestation and negotiation by vegans and those close to them. The article finds in the figure of the killjoy not only a frame by which to partly understand the negotiation of relationships between vegans and non-vegans but also an opportunity for further intersectional labour between veganism and feminism.

AbstractCrustose coralline algae (CCA) are a group of calcifying red macroalgae crucial to tropical coral reefs because they form crusts that cement together the reef framework1. Previous research into the responses of CCA to ocean warming (OW) and ocean acidification (OA) have found reductions in calcification rates and survival2,3, with magnitude of effect being species-specific. Responses of CCA to OW and OA could be linked to evolutionary divergence time and/or their underlying molecular biology, the role of either being unknown in CCA. Here we showSporolithon durum, a species from an earlier diverged lineage that exhibits low sensitivity to climate stressors, had little change in metabolic performance and did not significantly alter the expression of any genes when exposed to temperature and pH perturbations. In contrast,Porolithon onkodes, a species from a recently diverged lineage, reduced photosynthetic rates and had over 400 significantly differentially expressed genes in response to experimental treatments, with differential regulation of genes relating to physiological processes. We suggest earlier diverged CCA may be resistant to OW and OA conditions predicted for 2100, whereas taxa from more recently diverged lineages with demonstrated high sensitivity to climate stressors may have limited ability for acclimatisation.