Macrophytes from lakes in the eastern Pyrenees: community composition and ordination in relation to environmental factors

1. Thirty-six species of macrophytes (fourteen flowering plants, two quillworts, sixteen mosses and liverworts, and two algae) were collected in an extensive survey of 116 high mountain lakes in the eastern Pyrenees. Seventy per cent of the lakes showed macrophyte development. 2. The isoetids (Isoetes lacusiris, Isoetes setacea and Subularia aquatica) were the dominant growth form, although the natopotamid Sparganium angusifolium was the most widespread species. Potamids (Potamogeton spp., Ranunculus spp.), the alga Nitella gr. opaca and some mosses (Warnstorfia exannulata, Sphagnum denticulatum) were often present. 3. A multivariate ordination analysis (RDA-redundancy analysis) revealed that water chemistry, altitude and vegetation cover of the catchment, and nutrient availability are major environmental factors associated with macrophyte distribution along the eastern Pyrenean lakes. Isoetids prevailed in softwater oligotrophic lakes, potamids in relatively hardwater oligotrophic lakes, and Potamogeton natans and Callitriche palustris in small and eutrophic water bodies affected by the presence of cattle.     

Relationship between species longevity and larval ecology in nassariid gastropods

The relationship between duration in the fossil record and larval ecology, based on the protoconch morphology, has been analysed for 40 species of Nassarius Duméril, 1806. The lifespan of species with planktotrophic larval development is significantly longer than for those with nonplanktotrophic development. Many species, representing both forms of larval ecology, cluster around certain values of longevity. This macroevolutionary tendency does not correspond to a phylogenetic pattern, nor does it depend on the ecology of the adult forms. The results are explained by means of a hypothesis on dispersion capacity of the larvae, taking into account the particular geological history of the Mediterranean and eastern Atlantic regions during the Neogene. Additional hypotheses, relating to, e.g., ecological tolerance or trophism, are rejected as being unnecessary in this case. □ Longevity, larval ecology, gastropods, Nassariidae, Neogene, Mediterranean, Atlantic.     

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 treatmentcontact after first onset of a mental disorder in 15 countries in the WorldHealth Organization (WHO)''s World Mental Health (WMH) Surveys. Representativeface-to-face household surveys were conducted among 76,012 respondents aged18 and older in Belgium, Colombia, France, Germany, Israel, Italy, Japan,Lebanon, Mexico, the Netherlands, New Zealand, Nigeria, People''s Republicof China (Beijing and Shanghai), Spain, and the United States. The WHO CompositeInternational Diagnostic Interview (CIDI) was used to assess lifetime DSM-IVanxiety, mood, and substance use disorders. Ages of onset for individual disordersand ages of first treatment contact for each disorder were used to calculatethe extent of failure and delay in initial help seeking. The proportion oflifetime cases making treatment contact in the year of disorder onset rangedfrom 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 proportionof lifetime cases making treatment contact ranged from 15.2 to 95.0% for anxietydisorders, from 7.9 to 98.6% for mood disorders, and from 19.8 to 86.1% forsubstance use disorders. Median delays among cases eventually making contactranged from 3.0 to 30.0 years for anxiety disorders, from 1.0 to 14.0 yearsfor mood disorders, and from 6.0 to 18.0 years for substance use disorders.Failure and delays in treatment seeking were generally greater in developingcountries, older cohorts, men, and cases with earlier ages of onset. Theseresults show that failure and delays in initial help seeking are pervasiveproblems worldwide. Interventions to ensure prompt initial treatment contactsare needed to reduce the global burdens and hazards of untreated mental disorders.     

Faster returns on ‘leaf economics’ and different biogeochemical niche in invasive compared with native plant species

Plant‐invasive success is one of the most important current global changes in the biosphere. To understand which factors explain such success, we compared the foliar traits of 41 native and 47 alien‐invasive plant species in Oahu Island (Hawaii), a location with a highly endemic flora that has evolved in isolation and is currently vulnerable to invasions by exotic plant species. Foliar traits, which in most cases presented significant phylogenetic signal, i.e. closely related species tended to resemble each other due to shared ancestry, separated invasive from native species. Invasive species had lower leaf mass per area and enhanced capacities in terms of productivity (photosynthetic capacity) and nutrient capture both of macro‐ (N, P, K) and microelements (Fe, Ni, Cu and Zn). All these differences remain highly significant after removing the effects of phylogenetic history. Alien‐invasive species did not show higher efficiency at using limiting nutrient resources, but they got faster leaf economics returns and occupied a different biogeochemical niche, which helps to explain the success of invasive plants and suggests that potential increases in soil nutrient availability might favor further invasive plant success.