Microsatellites from the vairone Leuciscus souffia (Pisces: Cyprinidae) and their application to closely related species

Eleven microsatellites were isolated from the vairone Leuciscus souffia (Risso 1826), an endangered fish that inhabits river systems in and around the Alps in Europe. The level of genetic diversity was assessed in 29 individuals of the subspecies L. s. souffia, and their variability was further estimated in seven individuals of a different subspecies, L. s. muticellus. Eight of these microsatellite loci were also applied to seven closely related cyprinid species. Availability of the reported microsatellite loci will facilitate the investigation of population genetic structure of these species with applications for the development of conservation strategies and phylogeographical approaches.     

Delay and failure in treatment seeking after first onset of mental disorders in the World Health Organization's World Mental Health Survey Initiative

Data are presented on patterns of failure and delay in making initial treatment contact after first onset of a mental disorder in 15 countries in the World Health Organization (WHO)''s World Mental Health (WMH) Surveys. Representative face-to-face household surveys were conducted among 76,012 respondents aged 18 and older in Belgium, Colombia, France, Germany, Israel, Italy, Japan, Lebanon, Mexico, the Netherlands, New Zealand, Nigeria, People''s Republic of China (Beijing and Shanghai), Spain, and the United States. The WHO Composite International Diagnostic Interview (CIDI) was used to assess lifetime DSM-IV anxiety, mood, and substance use disorders. Ages of onset for individual disorders and ages of first treatment contact for each disorder were used to calculate the extent of failure and delay in initial help seeking. The proportion of lifetime cases making treatment contact in the year of disorder onset ranged from 0.8 to 36.4% for anxiety disorders, from 6.0 to 52.1% for mood disorders, and from 0.9 to 18.6% for substance use disorders. By 50 years, the proportion of lifetime cases making treatment contact ranged from 15.2 to 95.0% for anxiety disorders, from 7.9 to 98.6% for mood disorders, and from 19.8 to 86.1% for substance use disorders. Median delays among cases eventually making contact ranged from 3.0 to 30.0 years for anxiety disorders, from 1.0 to 14.0 years for mood disorders, and from 6.0 to 18.0 years for substance use disorders. Failure and delays in treatment seeking were generally greater in developing countries, older cohorts, men, and cases with earlier ages of onset. These results show that failure and delays in initial help seeking are pervasive problems worldwide. Interventions to ensure prompt initial treatment contacts are needed to reduce the global burdens and hazards of untreated mental disorders.     

Genome size rather than content might affect call properties in toads of three ploidy levels (Anura: Bufonidae: Bufo viridis subgroup)

In vertebrates, genome size has been shown to correlate with nuclear and cell sizes, and influences phenotypic features, such as brain complexity. In three different anuran families, advertisement calls of polyploids exhibit longer notes and intervals than diploids, and difference in cellular dimensions have been hypothesized to cause these modifications. We investigated this phenomenon in green toads (Bufo viridis subgroup) of three ploidy levels, in a different call type (release calls) that may evolve independently from advertisement calls, examining 1205 calls, from ten species, subspecies, and hybrid forms. Significant differences between pulse rates of six diploid and four polyploid (3n, 4n) green toad forms across a range of temperatures from 7 to 27 °C were found. Laboratory data supported differences in pulse rates of triploids vs. tetraploids, but failed to reach significance when including field recordings. This study supports the idea that genome size, irrespective of call type, phylogenetic context, and geographical background, might affect call properties in anurans and suggests a common principle governing this relationship. The nuclear‐cell size ratio, affected by genome size, seems the most plausible explanation. However, we cannot rule out hypotheses under which call‐influencing genes from an unexamined diploid ancestral species might also affect call properties in the hybrid‐origin polyploids. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 584–590.     

Response of plant species and life form diversity to variable fire histories and biomass in the jarrah forest of south‐west Australia

Frequent fires reduce the abundance of woody plant species and favour herbaceous species. Plant species richness also tends to increase with decreasing vegetation biomass and cover due to reduced competition for light. We assessed the influence of variable fire histories and site biomass on the following diversity measures: woody and herbaceous species richness, overall species richness and evenness, and life form evenness (i.e. the relative abundance or dominance among six herbaceous and six woody plant life forms), across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands in south‐west Australia. Fire frequency was defined as the total number of fires over a 30‐year period. Overall species richness and species evenness did not vary with fire frequency or biomass. However, there were more herbaceous species (particularly rushes, geophytes and herbs) where there were fewer shrubs and low biomass, suggesting that more herbaceous species coexist where dominance by shrubs is low. Frequently burnt plots also had lower number and abundance of shrub species. Life form evenness was also higher at both high fire frequency and low biomass sites. These results suggest that the impact of fire frequency and biomass on vegetation composition is mediated by local interactions among different life forms rather than among individual species. Our results demonstrate that measuring the variation in the relative diversity of different woody and herbaceous life forms is crucial to understanding the compositional response of forests and other structurally complex vegetation communities to changes in disturbance regime such as increased fire frequency.     

Effect of water availability on leaf water isotopic enrichment in beech seedlings shows limitations of current fractionation models

Current models of leaf water enrichment predict that the differences between isotopic enrichment of water at the site of evaporation (Δ_e) and mean lamina leaf water enrichment (Δ_L) depend on transpiration rates ( E ), modulated by the scaled effective length ( L ) of water isotope movement in the leaf. However, variations in leaf parameters in response to changing environmental conditions might cause changes in the water path and thus L . We measured the diel course of Δ_L for ¹⁸O and ²H in beech seedlings under well-watered and water-limited conditions. We applied evaporative enrichment models of increasing complexity to predict Δ_e and Δ_L, and estimated L from model fits. Water-limited plants showed moderate drought stress, with lower stomatal conductance, E and stem water potential than the control. Despite having double E , the divergence between Δ_e and Δ_L was lower in well-watered than in water-limited plants, and thus, L should have changed to counteract differences in E . Indeed, L was about threefold higher in water-limited plants, regardless of the models used. We conclude that L changes with plant water status far beyond the variations explained by water content and other measured variables, thus limiting the use of current evaporative models under changing environmental conditions.     

Bioethanol production from sugarcane and emissions of greenhouse gases – known and unknowns

Bioethanol production from sugarcane is discussed as an alternative energy source to reduce dependencies of regional economies on fossil fuels. Even though bioethanol production from sugarcane is considered to be a beneficial and cost‐effective greenhouse gas (GHG) mitigation strategy, it is still a matter of controversy due to insufficient information on the total GHG balance of this system. Aside from the necessity to account for the impact of land use change (LUC), soil N₂O emissions during sugarcane production and emissions of GHG due to preharvest burning may significantly impact the GHG balance. Based on a thorough literature review, we show that direct N₂O emissions from sugarcane fields due to nitrogen (N) fertilization result in an emission factor of 3.87±1.16% which is much higher than suggested by IPCC (1%). N₂O emissions from N fertilization accounted for 40% of the total GHG emissions from ethanol–sugarcane production, with an additional 17% from trash burning. If LUC‐related GHG emissions are considered, the total GHG balance turns negative mainly due to vegetation carbon losses. Our study also shows that major gaps in knowledge still exist about GHG sources related to agricultural management during sugarcane production, e.g. effects of irrigation, vinasse and filter cake application. Therefore, more studies are needed to assess if bioethanol from sugarcane is a viable option to reduce energy‐related GHG emissions.     

Volcanic explosive eruptions of the Vesuvio decrease tree-ring growth but not photosynthetic rates in the surrounding forests

Volcanic eruptions impact the global and the hemispheric climate, but it is still unknown how and to what degree they force the climate system and in particular the global carbon cycle. In this paper, the relationships between individual eruptions (reconstructed for the past using written records), tree primary productivity (estimated using ring widths), photosynthetic rate and stomatal conductance (assessed by carbon and oxygen isotope data) are investigated, to understand the impact of volcanic eruptions on net primary production. Data from a mixed stand of Fagus sylvatica L. and Acer pseudoplatanus L. located in the area of the Vesuvio volcanic complex (Southern Italy) showed a significant decrease in ring width following each eruption. Isotope analyses indicate a change in climatic conditions after such events. Specifically, the lower oxygen isotope ratio in the tree‐ring cellulose strongly suggests an increase in relative humidity and a decrease in temperature, with the latter resulting in a strong limitation to tree‐ring growth. The carbon isotope ratio was only moderately but not significantly reduced in the years of volcanic eruption, suggesting no major changes in C fixation rates. This work is a case study on the effects of volcanic eruptions resulting in strong climatic changes on the local scale. This is an opportunity to explore the process and causal relationships between climatic changes and the response of the vegetation. Thus, we propose here a realistic model scenario, from which we can extrapolate to global scales and improve our interpretations of results of global studies.