bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plant diversity and ecosystem multifunctionality peak at intermediate levels of woody cover in global drylands
Authors: Soliveres Santiago , Maestre Fernando T. , Eldridge David J. , Delgado‐Baquerizo Manuel , Quero José Luis , Bowker Matthew A. , Gallardo Antonio 
Published: September 2014

AbstractAimThe global spread of woody plants into grasslands is predicted to increase over the coming century. While there is general agreement regarding the anthropogenic causes of this phenomenon, its ecological consequences are less certain. We analysed how woody vegetation of differing cover affects plant diversity (richness and evenness) and the surrogates of multiple ecosystem processes (multifunctionality) in global drylands, and how these change with aridity.LocationTwo hundred and twenty‐four dryland sites from all continents except Antarctica, widely differing in their environmental conditions (from arid to dry‐subhumid sites) and relative woody cover (from 0 to 100%).MethodsUsing a standardized field survey, we measured the cover, richness and evenness of perennial vegetation. At each site, we measured 14 soil variables related to fertility and the build‐up of nutrient pools. These variables are critical for maintaining ecosystem functioning in drylands.ResultsSpecies richness and ecosystem multifunctionality were strongly related to woody vegetation, with both variables peaking at a relative woody cover (RWC) of 41–60%. This relationship shifted with aridity. We observed linear positive effects of RWC in dry‐subhumid sites. These positive trends shifted to hump‐shaped RWC–diversity and multifunctionality relationships under semi‐arid environments. Finally, hump‐shaped (richness, evenness) or linear negative (multifunctionality) effects of RWC were found under the most arid conditions.Main conclusionsPlant diversity and multifunctionality peaked at intermediate levels of woody cover, although this relationship became increasingly positive in wetter environments. This comprehensive study accounts for multiple ecosystem attributes across a range of levels of woody cover and environmental conditions. Our results help us to reconcile contrasting views of woody encroachment found in the current literature and can be used to improve predictions of the likely effects of encroachment on biodiversity and ecosystem services.
Reassessing global change research priorities in mediterranean terrestrial ecosystems: how far have we come and where do we go from here?
Authors: Doblas‐Miranda E. , Martínez‐Vilalta J. , Lloret F. , Álvarez A. , Ávila A. , Bonet F. J. , Brotons L. , Castro J. , Curiel Yuste J. , Díaz M. , Ferrandis P. , García‐Hurtado E. , Iriondo J. M. , Keenan T. F. , Latron J. , Llusià J. , Loepfe L. , Mayol M. , Moré G. , Moya D. , Peñuelas J. , Pons X. , Poyatos R. , Sardans J. , Sus O. , Vallejo V. R. , Vayreda J. , Retana J. 
Published: September 2014

AbstractAimMediterranean terrestrial ecosystems serve as reference laboratories for the investigation of global change because of their transitional climate, the high spatiotemporal variability of their environmental conditions, a rich and unique biodiversity and a wide range of socio‐economic conditions. As scientific development and environmental pressures increase, it is increasingly necessary to evaluate recent progress and to challenge research priorities in the face of global change.LocationMediterranean terrestrial ecosystems.MethodsThis article revisits the research priorities proposed in a 1998 assessment.ResultsA new set of research priorities is proposed: (1) to establish the role of the landscape mosaic on fire‐spread; (2) to further research the combined effect of different drivers on pest expansion; (3) to address the interaction between drivers of global change and recent forest management practices; (4) to obtain more realistic information on the impacts of global change and ecosystem services; (5) to assess forest mortality events associated with climatic extremes; (6) to focus global change research on identifying and managing vulnerable areas; (7) to use the functional traits concept to study resilience after disturbance; (8) to study the relationship between genotypic and phenotypic diversity as a source of forest resilience; (9) to understand the balance betweenCstorage and water resources; (10) to analyse the interplay between landscape‐scale processes and biodiversity conservation; (11) to refine models by including interactions between drivers and socio‐economic contexts; (12) to understand forest–atmosphere feedbacks; (13) to represent key mechanisms linking plant hydraulics with landscape hydrology.Main conclusions(1) The interactive nature of different global change drivers remains poorly understood. (2) There is a critical need for the rapid development of regional‐ and global‐scale models that are more tightly connected with large‐scale experiments, data networks and management practice. (3) More attention should be directed to drought‐related forest decline and the current relevance of historical land use.
Vulnerability of biodiversity hotspots to global change
Authors: Bellard Céline , Leclerc Camille , Leroy Boris , Bakkenes Michel , Veloz Samuel , Thuiller Wilfried , Courchamp Franck 
Published: September 2014

AbstractAimGlobal changes are predicted to have severe consequences for biodiversity; 34 biodiversity hotspots have become international priorities for conservation, with important efforts allocated to their preservation, but the potential effects of global changes on hotspots have so far received relatively little attention. We investigate whether hotspots are quantitatively and qualitatively threatened to the same order of magnitude by the combined effects of global changes.LocationWorldwide, in 34 biodiversity hotspots.MethodsWe quantify (1) the exposure of hotspots to climate change, by estimating the novelty of future climates and the disappearance of extant climates using climate dissimilarity analyses, (2) each hotspot's vulnerability to land modification and degradation by quantifying changes in land‐cover variables over the entire habitat, and (3) the future suitability of distribution ranges of ‘100 of the world's worst invasive alien species’, by characterizing the combined effects of climate and land‐use changes on the future distribution ranges of these species.ResultsOur findings show that hotspots may experience an average loss of 31% of their area under analogue climate, with some hotspots more affected than others (e.g. Polynesia–Micronesia). The greatest climate change was projected in low‐latitude hotspots. The hotspots were on average suitable for 17% of the considered invasive species. Hotspots that are mainly islands or groups of islands were disproportionally suitable for a high number of invasive species both currently and in the future. We also showed that hotspots will increase their area of pasture in the future. Finally, combining the three threats, we identified the Atlantic forest, Cape Floristic Region and Polynesia–Micronesia as particularly vulnerable to global changes.Main conclusionsGiven our estimates of hotspot vulnerability to changes, close monitoring is now required to evaluate the biodiversity responses to future changes and to test our projections against observations.
Environmental niche modelling fails to predict Last Glacial Maximum refugia: niche shifts, microrefugia or incorrect palaeoclimate estimates?
Authors: Worth James R. P. , Williamson Grant J. , Sakaguchi Shota , Nevill Paul G. , Jordan Greg J. 
Published: September 2014

AbstractAimMany predictions of responses to future climate change utilize ecological niche models (ENMs). We assess the capacity of these models to predict species distributions under conditions that differ from the current environment by testing whether they can predict past distributions of species.LocationFrom 43° S to 31° S in south‐eastern Australia (including Tasmania).MethodsWe studied three dominant tree species of temperate Australian mesic forests, Atherosperma moschatum, Eucalyptus regnans and Nothofagus cunninghamii. Phylogeographic evidence indicates that these species each survived the Last Glacial Maximum (LGM) in multiple refugia. We modelled the current distribution of each species and projected those models onto LGM climates under six palaeoclimatic scenarios. The support for phylogeographic‐based glacial refugia was estimated under each scenario using three different thresholds for inferring species presence/absence.ResultsThe LGM models under scenarios that allowed for a realistic level of rainfall failed to predict survival of the study species in refugia identified from genetic evidence, apart from those in perhumid western Tasmania.Main conclusionsCorrect prediction of nearly all modern occurrences of the species suggests that this failure of ENMs to predict refugial survival was not methodological. Rather we conclude that the existing realized niches of these species may have changed since the LGM. Such niche changes may have involved the occurrence of non‐analogue climates in the LGM and some significant alteration of fundamental niche (for at least E. regnans). Our results emphasize that predictions of future impacts of climate change on biodiversity will benefit from awareness of the limitations of ENMs in predicting the extinction of populations/species. Greater knowledge of how niches have changed through time and how this relates to the characteristics of species is needed to improve the reliability of ENMs. Niche changes in plants may also affect palaeoclimatic estimates based on fossil pollen.
Beyond “The Ecological Indian” and “Virgin Soil Epidemics”: New Perspectives on Native Americans and the Environment
Authors: Rice James D. 
Published: September 2014

AbstractIndians figured prominently in many of the now‐classic works that helped to define the burgeoning new field of environmental history during the 1970s and 1980s. Although a great deal of new and interesting work on Native Americans and the environment has been conducted since 1990, most of it has been produced not by scholars who think of themselves as environmental historians, but rather by archaeologists, anthropologists, historians of Native Americans, and Native people themselves. This essay surveys this new, multidisciplinary literature, and suggests some ways in which non‐specialists, and particularly environmental historians, might fruitfully engage with it.
Nanometre‐scale investigations by atomic force microscopy into the effect of different treatments on the surface structure of hair
Authors: Durkan C. , Wang N. 
Published: September 2014

SynopsisObjectiveTo investigate the effect of different washing regimes on the surface of human hair at the nanometre scale – comparable to the size of typical deposits left behind by commercial products.MethodsAtomic force microscopy (AFM) and related techniques.ResultsIt can be directly seen that washing hair using commercial hair care products removes deposits that naturally form on the shaft, revealing the underlying structure of the hair, whereas in many cases leaving new deposits behind. The spatial distribution of these deposits is explored and quantified. The spatial distribution of the surface charge of pristine hair is mapped, and the electrical screening effect of deposits is directly observed. We also show that the roughness of the treated hair depends directly on the type of product used, with a marked difference between shampoo and conditioner. Some products leave isolated deposits behind, whereas others leave layers of material behind which wet the hair surface.ConclusionAtomic force microscopy and the related techniques we have employed in a forensic approach is able to distinguish between different hair care products on the basis of the deposits they leave behind. This opens up the capability of further analysis tools to complement already existing techniques.
Development of active chitosan films incorporating potassium sorbate or vanillin to extend the shelf life of butter cake
Authors: Sangsuwan Jurmkwan , Rattanapanone Nithiya , Pongsirikul Israpong 
Published: September 2014

SummaryActive film from chitosan was developed by adding potassium sorbate or vanillin as antimicrobial agents. The addition of potassium sorbate in the film's formula resulted in less transparency, lower strength, water permeability, while increased flexibility and oxygen permeability. Addition of vanillin in film resulted in more yellow of film colour, lower film's strength and permeability. After that, all films were used to wrap around butter cake. The inhibitory effect of film against mould was studied using commercial stretch film as control. Mould was observed on cake wrapped by stretch film and chitosan film on day 4 and 7, respectively, while mould was not observed on cake wrapped by chitosan film containing potassium sorbate or vanillin during 8‐day storage which agreed with the amount of mould enumeration on PDA. The quality of cake during storage at room temperature was also studied. Cake wrapped with film containing vanillin became more yellow. The sensory of all cake treatments were acceptable.
Role of Green Governance in Achieving Sustainable Urbanization in China
Authors: Fay Marianne , Wang Jin‐zhao , Draugelis Gailius , Deichmann Uwe 
Published: September 2014

AbstractSince economic reforms began in 1978, China's urban population has increased by half a billion. Over the next 20 years, cities will likely add another 300 million people through local population growth, migration and the integration of nearby rural areas. Cities account for the majority of resource use and pollution so achieving greener growth will depend on developing and implementing a more sustainable urbanization model. China's leaders have responded to these challenges with ambitious goals and comprehensive environmental laws and regulations. These have so far not significantly reduced the harm from air, water and soil pollution: in large measure because China's green governance does not match its green ambitions. Drawing on the World Bank's work on green growth and a recent joint urbanization study by the Development Research Center of China's State Council and the World Bank, this paper reviews recent academic research on green governance in urban China and discusses its main implications in the context of emerging global green growth concepts.
Validated Prediction of the Strength Size Effect in Polycrystalline Silicon Using the Three‐Parameter Weibull Function
Authors: Saleh Mohamed E. , Beuth Jack L. , de Boer Maarten P. 
Published: September 2014

It has recently been shown that a three‐parameter Weibull function with a large threshold strength of ≈2 GPa is needed to accurately describe the failure strength statistics of micromachined polycrystalline silicon samples. Here, we explore how to apply this function to predict strength size effects over a size range of 100. A two‐parameter function is unsatisfactory in predicting the size effect. If a three‐parameter Weibull fit to only the largest specimen is used, the prediction also does not satisfactorily agree with strength data in smaller specimens. The prediction is greatly improved if the two largest specimens, a factor of 10 different in size, are used for fitting. It is further demonstrated that the threshold strength depends on geometry in notched samples due to their large stress gradients.
The influence of geological history on diversification in insular species: genetic and morphological patterns of Micromeria Benth. (Lamiaceae) in Tenerife (Canary archipelago)
Authors: Puppo Pamela , Curto Manuel , Velo‐Antón Guillermo , Pérez de Paz Pedro Luis , Meimberg Harald 
Published: September 2014

AbstractAimUsing phylogenetic and morphometric approaches, our study aims to understand the diversification process of the two groups of Micromeria species in Tenerife: the species restricted to the palaeoislands, and the species widely distributed in the younger part of the island.LocationTenerife, Canary Islands.MethodsWe calculated a calibrated phylogeny and a Neighbor‐Net network based on eight nuclear loci from 37 samples: 22 of the 8 species currently recognized in Tenerife, and 15 of their closest relatives occurring in neighbouring islands and continental populations. We performed a principal components analysis (PCA) of 27 morphological characters from 54 specimens sampled from Tenerife.ResultsOur phylogeny showed that the species from Tenerife can be subdivided into three main clades: one composed of the species inhabiting the palaeoisland of Anaga (M. teneriffae, M. glomerata and M. rivas‐martinezii); another composed of the species present in the palaeoisland of Teno (M. densiflora); and a third group that includes all the central species (M. hyssopifolia, M. varia, M. lachnophylla and M. lasiophylla). Morphometric analyses indicated two main groups corresponding to the palaeoisland species and the central ones.Main conclusionsOur study points to a relationship between the diversification in Micromeria and the geological history of Tenerife. We conclude that Micromeria first arrived in Anaga where it diversified, subsequently colonized Teno and from there occupied the central part, presumably after the formation of the Teide volcano. The species of Micromeria in Tenerife constitute an interesting example of how species diversification on oceanic islands can be shaped by the island's geological history, which probably contributed to the high levels of endemism on Tenerife.
Pleistocene survival, regional genetic structure and interspecific gene flow among three northern peat‐mosses: Sphagnum inexspectatum, S. orientale and S. miyabeanum
Authors: Shaw A. Jonathan , Shaw Blanka , Stenøien Hans K. , Golinski G. Karen , Hassel Kristian , Flatberg Kjell Ivar 
Published: September 2014

AbstractAimArctic plant species are often characterized by a complex genetic structure because of changes in their population size, the fragmentation of metapopulation systems, extensive hybridization and allopolyploidization, and survival in disjunct refugia, historical features associated with Pleistocene glaciation. We assessed the biogeographical and genetic patterns in three closely related northern species of peat‐moss (Sphagnum inexspectatum, S. orientale and S. miyabeanum), especially interspecific hybridization, infraspecific geographical differentiation and Pleistocene survival in one or more refugial areas. We tested alternative hypotheses of refugial survival in three widely disjunct regions: eastern Asia, Alaska and Greenland.LocationNorth America (Canada, western USA and Greenland), China, Japan and Russia.MethodsFour hundred and forty‐three plants were genotyped at 12 microsatellite loci. Nucleotide sequences from 130 accessions for two plastid and two nuclear loci were used to reconstruct haplotype relationships. Population genetic analyses produced estimates of genetic diversity, levels of interspecific gene flow and rates of infraspecific intercontinental migration. Approximate Bayesian computation was used to test alternative biogeographical scenarios.ResultsWe found evidence of hybridization between two of the three species, but phylogenetic patterns are predominantly divergent rather than reticulate. Disjunct populations of one species, S. orientale, in Greenland, Alaska and China are genetically differentiated, but migration has occurred among all three metapopulation systems. Divergence‐time analyses strongly support the hypothesis that S. orientale survived the Last Glacial Maximum in Beringia and also in Greenland.Main conclusionsOur results indicate that Beringia served as a refugium for peat‐mosses, and therefore peatlands, which are currently extensive at high latitudes of the Northern Hemisphere. Sphagnum orientale also appears to have survived the Last Glacial Maximum in Greenland, indicating that the species persisted in multiple Pleistocene refugia. Phylogenetic patterns are relatively simple in these mosses compared with those commonly encountered in Arctic angiosperms.
Patch test results of hand eczema patients: relation to clinical types
Authors: Boonstra M.B. , Christoffers W.A. , Coenraads P.J. , Schuttelaar M.L.A. 
Published: September 2014

AbstractBackgroundAllergic contact dermatitis is a well‐known cause of hand eczema, although the influence of contact allergens on different clinical types of hand eczema remains still unclear.ObjectiveTo identify most common positive tested allergens among hand eczema patients and to define the relation between specific contact allergies and clinical types of hand eczema according to the guidelines of the Danish Contact Dermatitis Group (DCDG).MethodsWe included 1571 hand eczema subjects who were patch tested from 1 January 2002 to 31 December 2013. They were retrospectively classified according to the guidelines of the DCDG into six clinical types: recurrent vesicular hand eczema, chronic fissured hand eczema, hyperkeratotic palmar eczema, pulpitis, interdigital eczema and nummular hand eczema according to a newly developed flow chart. The prevalence of sensitizations and association with clinical type, atopic dermatitis, age and gender were studied.ResultsA total of 1395 subjects were classified into one of the six clinical types. The most frequently found clinical types were recurrent vesicular hand eczema (39.7%) and chronic fissured hand eczema (35.5%). Subjects with recurrent vesicular hand eczema were significantly more likely to have a contact allergy (OR 1.55), whereas subjects with hyperkeratotic palmar eczema and pulpitis were less likely to be sensitized (OR 0.51; OR 0.44). Overall, metals (nickel sulphate, cobalt chloride), fragrances and preservatives (methylchloroisothiazoline/methylisothiazoline, methyldibromoglutaronitrile) were the most frequent sensitizers in patients with hand eczema. This did not deviate in the different clinical types, although subjects with recurrent vesicular hand eczema were significantly more frequently sensitized to nickel sulphate and other allergens compared to other clinical types of hand eczema.ConclusionIn the diagnostic work up of hand eczema subjects with recurrent vesicular hand eczema should be patch tested, especially women of older age, although the need for patch testing in males with hyperkeratotic palmar eczema might be less imperative.