bluuebunny/crossref_metadata_2025_split huggingface dataset:
Managing fisheries for human and food security
Authors: McClanahan Tim , Allison Edward H , Cinner Joshua E 
Published: May 2013

AbstractWe evaluate the current status of the global marine fisheries using the frameworks of conflict, food security and vulnerability. Existing trends suggest that there is likely to be greater food insecurity and fisheries conflicts due to issues such as: declining fishery resources; a North–South divide in investment; changing consumption patterns; increasing reliance on fishery resources for coastal communities; and inescapable poverty traps creating by low net resource productivity and few alternatives. Consequently, managing fisheries from a food security perspective will become increasingly necessary, and we therefore briefly review fisheries from the perspective of food security and evaluate it using a vulnerability framework. Specifically, we describe three key components of vulnerability (exposure, sensitivity and adaptive capacity) for selected fisheries. This is followed by proposals to build the adaptive capacity of fisheries and recommendations to avoid future conflicts. Adaptive capacity attributes include assets, social flexibility and organization attributes, and learning. We present some key ways to build these aspects of the fishery to reduce the many potential environmental and social threats that increase the vulnerability of fisheries. Recommendations include fewer subsidies, reduced capital investment, precautionary management to minimize risks of ecosystem collapse, conservation of remaining resources, diversified portfolios of production and markets, and greater equity in contracts and distribution. Further, we recommend a contextual diagnostic and environmental justice framework to assess a range of options for fishery governance.
Individual and combined effects of fine sediment and the herbicide glyphosate on benthic macroinvertebrates and stream ecosystem function
Authors: Magbanua Francis S. , Townsend Colin R. , Hageman Kimberly J. , Matthaei Christoph D. 
Published: May 2013

Summary

Previous research on the combined action of various paired agricultural stressors in stream ecosystems has shown that non‐additive outcomes (i.e. synergisms or antagonisms) are more common than simple additive effects on communities, but the interplay between deposited fine sediment and widely used herbicides such as glyphosate as stressors is not well understood.

A 28‐day experiment in outdoor stream mesocosms simulated effects of varying levels of fine sediment and a glyphosate‐based herbicide on macroinvertebrates and ecosystem function (leaf breakdown) in a fully factorial repeated‐measures design. Our aim was to determine whether (i) increased levels of sediment and glyphosate had individual and/or additive combined effects on invertebrates and leaf breakdown, (ii) increased sediment reduced the toxicity of glyphosate (antagonistic multiple stressor interaction) or (iii) sediment‐adsorbed glyphosate prolonged the effects of exposure (synergistic interaction).

Sediment addition positively or negatively affected eight of the 10 most common invertebrate taxa colonising the mesocosms and increased or decreased the representation of 12 of 15 biological trait categories possessed by the invertebrates, while glyphosate addition negatively affected only two taxa and two invertebrate trait categories, indicating that glyphosate entering streams as a result of herbicide addition to farmland is less likely to be problematic for invertebrates than fine sediment from catchment erosion.

No significant overall sediment‐by‐glyphosate interaction was detected for invertebrate taxonomic or trait compositions or for any common individual taxon, trait or community metric, indicating that the two stressors were acting additively (i.e. without interaction), rather than synergistically or antagonistically.

Leaf breakdown rates (measured as mass and strength loss) were accelerated by sediment and glyphosate as individual stressors. Further, the two stressors interacted for leaf strength loss, with their combined effect being less than additive when both stressors were at their highest levels.

Population, community and ecosystem variables responded differently to multiple stressors, highlighting the value of combining structural, functional taxonomic and trait data to assess the effects of anthropogenic stressors.
Environmental, spatial and phylogenetic determinants of fish life‐history traits and functional composition of Australian rivers
Authors: Sternberg David , Kennard Mark J. 
Published: May 2013

Summary

The biogeography of freshwater fish is determined in part by large‐scale filters such as phylogenetic history, the spatial arrangement of catchments and environmental variability. Species are filtered from the regional pool if they possess a combination of functional traits enabling them to persist in the local environment. This article aims to quantify the relative importance of these large‐scale filters in determining spatial variation in freshwater fish life‐history traits and functional trait composition of Australian river basins.

We developed a database of 10 life‐history traits for 141 native freshwater fish species and compiled species distribution data for 123 river basins across the Australian continent. In order to partition the variation in the representation of life‐history trait into unique and overlapping components, we also quantified the degree of phylogenetic relatedness among species, the geographical arrangement of river basins throughout the landscape and 12 broad‐scale environmental factors. We then related life‐history trait composition to gradients of environmental variation by constrained multivariate ordination and simple linear regression.

Our explanatory matrices accounted for 86.8% of the total variation in life‐history trait composition at the river basin scale, of which 59.4% could be attributed to phylogeny and spatially structured environmental variation. This component represents the overlap among the broad‐scale filtering processes of phylogenetic history, spatial autocorrelation and environmental variability in accounting for the distribution of life‐history traits across Australian river basins.

Our analysis showed strong associations between suites of life‐history traits that define generation time and reproductive output and a strong climate–hydrological gradient across the landscape. We also showed significant correlations between specific environmental variables and a number of key life‐history traits that highlight the importance of trait‐mediated environmental filters at broad spatial scales.

This study advances our conceptual understanding of broad‐scale community assembly theory and has revealed trait–environment relationships at scales relevant to restoration and conservation of aquatic biodiversity. Our study provides greater insight into the determinants of spatial variation in fish species distributions and potentially addresses key scientific challenges, such as understanding how fish communities are assembled, and identifies the potential threats to, and responses of, these communities caused by environmental change.
Drought response of five conifer species under contrasting water availability suggests high vulnerability of Norway spruce and European larch
Authors: Lévesque Mathieu , Saurer Matthias , Siegwolf Rolf , Eilmann Britta , Brang Peter , Bugmann Harald , Rigling Andreas 
Published: May 2013

AbstractThe ability of tree species to cope with anticipated decrease in water availability is still poorly understood. We evaluated the potential of Norway spruce, Scots pine, European larch, black pine, and Douglas‐fir to withstand drought in a drier future climate by analyzing their past growth and physiological responses at a xeric and a mesic site in Central Europe using dendroecological methods. Earlywood, latewood, and total ring width, as well as the δ13C and δ18O in early‐ and latewood were measured and statistically related to a multiscalar soil water deficit index from 1961 to 2009. At the xeric site, δ13C values of all species were strongly linked to water deficits that lasted longer than 11 months, indicating a long‐term cumulative effect on the carbon pool. Trees at the xeric site were particularly sensitive to soil water recharge in the preceding autumn and early spring. The native species European larch and Norway spruce, growing close to their dry distribution limit at the xeric site, were found to be the most vulnerable species to soil water deficits. At the mesic site, summer water availability was critical for all species, whereas water availability prior to the growing season was less important. Trees at the mesic were more vulnerable to water deficits of shorter duration than the xeric site. We conclude that if summers become drier, trees growing on mesic sites will undergo significant growth reductions, whereas at their dry distribution limit in the Alps, tree growth of the highly sensitive spruce and larch may collapse, likely inducing dieback and compromising the provision of ecosystem services. However, the magnitude of these changes will be mediated strongly by soil water recharge in winter and thus water availability at the beginning of the growing season.
Dampening effects of long‐term experimental drought on growth and mortality rates of a Holm oak forest
Authors: Barbeta Adrià , Ogaya Romà , Peñuelas Josep 
Published: May 2013

AbstractForests respond to increasing intensities and frequencies of drought by reducing growth and with higher tree mortality rates. Little is known, however, about the long‐term consequences of generally drier conditions and more frequent extreme droughts. A Holm oak forest was exposed to experimental rainfall manipulation for 13 years to study the effect of increasing drought on growth and mortality of the dominant speciesQuercus ilex,Phillyrea latifolia,andArbutus unedo. The drought treatment reduced stem growth ofA. unedo(−66.5%) andQ. ilex(−17.5%), whereasP. latifoliaremained unaffected. Higher stem mortality rates were noticeable inQ. ilex(+42.3%), but not in the other two species. Stem growth was a function of the drought index of early spring in the three species. Stem mortality rates depended on the drought index of winter and spring forQ. ilexand in spring and summer forP. latifolia,but showed no relation to climate inA. unedo. Following a long and intense drought (2005–2006), stem growth ofQ. ilexandP. latifoliaincreased, whereas it decreased inA. unedo.Q. ilexalso enhanced its survival after this period. Furthermore, the effect of drought treatment on stem growth inQ. ilexandA. unedowas attenuated as the study progressed. These results highlight the different vulnerabilities of Mediterranean species to more frequent and intense droughts, which may lead to partial species substitution and changes in forest structure and thus in carbon uptake. The response to drought, however, changed over time. Decreased intra‐ and interspecific competition after extreme events with high mortality, together with probable morphological and physiological acclimation to drought during the study period, may, at least in the short term, buffer forests against drier conditions. The long‐term effects of drought consequently deserve more attention, because the ecosystemic responses are unlikely to be stable over time.Nontechnical summaryIn this study, we evaluate the effect of long‐term (13 years) experimental drought on growth and mortality rates of three forest Mediterranean species, and their response to the different intensities and durations of natural drought. We provide evidence for species‐specific responses to drought, what may eventually lead to a partial community shift favoring the more drought‐resistant species. However, we also report a dampening of the treatment effect on the two drought‐sensitive species, which may indicate a potential adaptation to drier conditions at the ecosystem or population level. These results are thus relevant to account for the stabilizing processes that would alter the initial response of ecosystem to drought through changes in plant physiology, morphology, and demography compensation.
Consequences of the introduction of exotic and translocated species and future extirpations on the functional diversity of freshwater fish assemblages
Authors: Matsuzaki Shin‐ichiro S. , Sasaki Takehiro , Akasaka Munemitsu 
Published: May 2013

AbstractAimTo explore the effects of the introduction of exotic and translocated species and possible future extirpation of native species on the functional diversity (FD) of freshwater fish assemblages.LocationJapanese archipelago.MethodsWe examined spatio‐temporal changes in species richness, FD, functional richness (the number of trait‐based functional groups), and the functional group composition between historical and current fish assemblages for 27 eco‐regions, and compared the relative effects of the introduction of exotic and translocated species on FD. We also used a null model approach to determine the assembly patterns and the extent of functional redundancy. Finally, we determined the effect of the loss of endangered species on FD by comparing the observed losses with simulated random loss.ResultsThrough the introductions of non‐native species, the species richness, FD and functional richness of the fish assemblages increased 2.4‐, 1.6‐ and 2.1‐fold, respectively. The functional group composition also changed largely through the additions of new functional groups. Exotic species had a significantly greater effect size than translocated species, but there were no differences in the overall net effects of exotic and translocated species. Null modelling approaches showed that the observed FD was higher than expected by chance (i.e. trait divergent) in both historical and current assemblages. There was also low functional redundancy. In our simulation, FD decreased in proportion to the loss of species, independent of whether the species were endangered.Main conclusionsWe demonstrated that both exotic and translocated species may change FD and functional group composition, which might have dramatic consequences for ecosystem processes. We suggest that the future extirpation of even a few native species can cause a substantial loss of FD. Our findings emphasize the need to improve conservation strategies based on species richness and conservation status, and to incorporate translocated species into targets of the management of non‐native species.
Phenotypic and phylogenetic correlates of geographic range size inCanadian freshwater fishes
Authors: Blanchet Simon , Reyjol Yorick , April Julien , Mandrak Nicholas E. , Rodríguez Marco A. , Bernatchez Louis , Magnan Pierre 
Published: May 2013

AbstractAimWe investigated the relationship between geographic range size (GRS), longitude and latitude (Rapoport's rule) inCanadian freshwater fishes. We tested hypotheses regarding the phenotypic and phylogenetic determinants ofGRSto unravel processes driving the spatial patterns ofGRSinCanada. BecauseGRSis negatively correlated with extinction risk, we also aimed at identifying biological proxies that may be used to predict extinction risks.LocationNorth‐America,CanadianShield.MethodsWe built a database combining range area, seven ecological traits, and a molecular phylogeny for nativeCanadian freshwater fishes. We tested latitudinal and longitudinal patterns inGRSby the mean ofPearson correlations. We combined phylogenetic generalized least squares (PGLS) models and a model selection procedure to tease apart hypotheses (and hence ecological traits) that best explainedGRSin our dataset.PGLSs were also used to explore relationships between ecological traits, phylogeny, and species mid‐range latitude and longitude. Partial regressions were used to determine direct and indirect relationships driving spatial patterns ofGRSinCanadian freshwater fishes.ResultsThere was a significant and positive correlation betweenGRS, latitude and longitude. According toPGLSs, three ecological traits, related to the habitat use, migratory and thermal tolerance hypotheses, were significantly correlated withGRS, mid‐range longitude and mid‐range latitude. Two traits related to locomotion were further related toGRS. There was no phylogenetic effect onGRS(i.e. no phylogenetic conservatism). Partial regressions revealed complex direct and indirect relationships between ecological traits, mid‐range latitude, mid‐range longitude andGRS.Main conclusionsOur results show that traits related to the ability to use dispersal corridors, as well as traits directly related to mobility, are useful in understanding biodiversity patterns such as Rapoport's rule. However, because of a weak explanatory power, we conclude that using biological proxies ofGRSto predict species at risk of extinction would be premature.
Phylogenetic beta diversity of angiosperms in North America
Authors: Qian Hong , Swenson Nathan G. , Zhang Jinlong 
Published: May 2013

AbstractAimEcologists have generally agreed that beta diversity is a key component of global patterns of species richness. Incorporating phylogenetic information into the study of beta diversity allows researchers to identify the degree to which the shared evolutionary histories of species explain ecological patterns observed today. For example, phylogenetic analyses can determine whether closely related species tend to occupy similar positions along broad climatic gradients and whether this explains the compositional turnover along these gradients. Despite the promise of phylogenetic beta diversity analyses, few continental‐scale investigations exist. Here, we quantify the phylogenetic beta diversity and taxonomic beta diversity of the angiosperm flora across North America. We relate these metrics to one another and to geographical and environmental distances to uncover the phylogenetic signal underlying species compositional turnover.LocationNorth America.MethodSeventy‐one regional floras were used and assigned into five latitudinal zones and two longitudinal bands. The Sørensen index and PhyloSor index were used to quantify taxonomic similarity and phylogenetic similarity, respectively, between floras, and were related to geographical and environmental distances.ResultsPhylogenetic similarity between floras is strongly correlated with taxonomic similarity, is higher in eastern North America than in western North America, and increases strikingly with latitude. Geographical and environmental distances together explained on average about 76% of the variation in phylogenetic beta diversity with environmental distance explaining more variation in phylogenetic similarity in three of the four latitudinal bands examined.Main conclusionsThe results show that phylogenetic beta diversity is consistently lower than taxonomic beta diversity, which suggests that the spatial turnover of species in the study system is predominantly the spatial turnover of closely related species and not distantly related species. Thus, the turnover of angiosperm floras in North America is best explained by small divergences along environmental axes for closely related species and a gradual turnover of lineages through space.
Chronic ethanol diet increases regulatory T‐cell activity and inhibits hepatitis C virus core‐specific cellular immune responses in mice
Authors: Ortiz Vivian , Wands Jack R. 
Published: May 2013

AimChronic ethanol consumption is associated with persistent hepatitis C viral (HCV) infection. This study explores the role of the host cellular immune response to HCV core protein in a murine model and how chronic ethanol consumption alters T‐cell regulatory (Treg) populations.MethodsBALB/c mice were fed an isocaloric control or ethanol liquid diet. Dendritic cells (DC) were isolated after expansion with a hFl3tL‐expression plasmid and subsequently transfected with HCV core protein. Core‐containing DC (1 × 106) were s.c. injected (×3) in mice every 2 weeks. Splenocytes from immunized mice were isolated and stimulated with HCV core protein to measure generation of viral antigen‐specific Treg, as well as secretion of interleukin (IL)‐2, tumor necrosis factor (TNF)‐α and IL‐4. Cytotoxicity was measured by lactate dehydrogenase release from HCV core‐expressing syngeneic SP2/19 myeloma cells.ResultsSplenocytes from mice immunized with ethanol‐derived and HCV core‐loaded DC exhibited significantly lower in vitro cytotoxicity compared to mice immunized with HCV core‐loaded DC derived from isocaloric pair‐fed controls. Stimulation with HCV core protein triggered higher IL‐2, TNF‐α and IL‐4 release in splenocytes following immunization with core‐loaded DC derived from controls as compared to chronic ethanol‐fed mice. Splenocytes derived from mice immunized with core‐loaded DC isolated from ethanol‐fed mice exhibited a significantly higher CD25+FOXP3+ and CD4+FOXP3+Treg population.ConclusionThese results suggest that immunization with HCV core‐containing DC from ethanol‐fed mice induces an increase in the CD25+FOXP3+ and CD4+FOXP3+Treg population and may suppress HCV core‐specific CD4+ and CD8+ T‐cell immune responses.
Macrophage colony‐stimulating factor plays a pivotal role in chemically induced hepatocellular carcinoma in mice
Authors: Hara Michio , Kono Hiroshi , Furuya Shinji , Hirayama Kazuyoshi , Tsuchiya Masato , Fujii Hideki 
Published: May 2013

AimThe specific purpose of this study was to investigate the role of macrophage colony‐stimulating factor (M‐CSF) in initiation and progression of hepatocellular carcinoma usingM‐CSF‐deficient mice.MethodsM‐CSF‐deficient (osteopetrotic: op/op) and their littermate (LM) mice were i.p. injected with diethylnitrosamine (DEN) to induce hepatocellular carcinoma. Twenty‐eight weeks afterDENadministration, the tumor incidence rate and serumM‐CSFlevels were assessed. Furthermore, distribution of the activated macrophages and the mRNAexpression ofCD163andCD204were evaluated. Moreover, angiogenesis was analyzed in tumors. In another set of experiments, apoptosis and proliferation of the hepatocytes were examined in the acute phase afterDENadministration. Isolated hepatic macrophages were cultured with or withoutM‐CSF, and vascular endothelial growth factor (VEGF) production was assessed by enzyme‐linked immunoassay.ResultsTumor incidence was significantly reduced in the op/op compared with theLMmice. SerumM‐CSFlevels were increased in the carcinogenesis models of theLMmice. Hepatic macrophages were found only in tumors in the op/op but in both normal liver tissue and tumors in theLMmice. In the op/op group, the mRNAexpression of inflammatory cytokines was significantly lower compared with theLMmice. Furthermore, apoptosis was significantly increased in the op/op than theLMmice. Angiogenesis increased in liver tumors from theLMcompared with the op/op mice. Production ofVEGFwas greater in the hepatic macrophages incubated withM‐CSFcompared with those withoutM‐CSF.ConclusionThus,M‐CSFis involved in the progression of chemically induced hepatocarcinogenesis.