Intensive human land uses negatively affect vertebrate functional diversity

Land-use change is the leading driver of global biodiversity loss thus characterising its impacts on the functional structure of ecological communities is an urgent challenge. Using a database describing vertebrate assemblages in different land uses, we assess how the type and intensity of land use affect the functional diversity of vertebrates globally. We find that human land uses alter local functional structure by driving declines in functional diversity, with the strongest effects in the most disturbed land uses (intensely used urban sites, cropland and pastures), and among amphibians and birds. Both tropical and temperate areas experience important functional losses, which are only partially offset by functional gains. Tropical assemblages are more likely to show decreases in functional diversity that exceed those expected from species loss alone. Our results indicate that land-use change non-randomly reshapes the functional structure of vertebrate assemblages, raising concerns about the continuation of ecological processes sustained by vertebrates

Global gaps in trait data for terrestrial vertebrates

AIM: Trait data are increasingly being used in studies investigating the impacts of global changes on the structure and functioning of ecological communities. Despite a growing number of trait data collations for terrestrial vertebrates, there is to date no global assessment of the gaps and biases the data present. Here, we assess whether terrestrial vertebrate trait data are taxonomically, spatially and phylogenetically biased. LOCATION: Global. TIME PERIOD: Present. MAJOR TAXA STUDIED: Terrestrial vertebrates. METHODS: We compile seven ecological traits and quantify coverage as the proportion of species for which an estimate is available. For a species, we define completeness as the proportion of non‐missing values across traits. We assess whether coverage and completeness differ across classes and examine phylogenetic biases in trait data. To investigate spatial biases, we test whether wider‐ranging species have more complete trait data than narrow‐ranging species. Additionally, we test whether species‐rich regions, which are of most concern for conservation, are less well sampled than species‐poor regions. RESULTS: Mammals and birds are well sampled even in species‐rich regions. For reptiles and amphibians (herptiles), only body size presents a high coverage (>80%), in addition to habitat‐related variables (amphibians). Herptiles are poorly sampled for other traits. The shortfalls are particularly acute in some species‐rich regions and for certain clades. Across all classes, geographically rarer species have less complete trait information. MAIN CONCLUSIONS: Trait information is less available on average in some of the most diverse areas and in geographically rarer species, both of which crucial for biodiversity conservation. Gaps in trait data might impede our ability to conduct large‐scale analyses, whereas biases can impact the validity of extrapolations. A short‐term solution to the problem is to estimate missing trait data using imputation techniques, whereas a longer‐term and more robust filling of existing gaps requires continued data‐collection efforts

Effects of rarity form on species' responses to land use

Anthropogenic land-use change causes substantial changes in local and global biodiversity. Rare and common species can differ in sensitivity to land-use change, with rare species expected to be more negatively affected. Rarity may be defined in terms of geographic range size, population density or breadth of habitat requirements. How these three forms of rarity interact in determining global responses to land use is yet to be assessed. Using global data representing 912 vertebrate species, we test for differences in the responses to land use of species characterised by different types of rarity. Species considered rare with respect to all three forms of rarity showed particularly strong declines in disturbed land uses (more than 40% of species and 30% of individuals in the most disturbed land uses). In contrast, species common both geographically and numerically, and with broad habitat requirements, showed strong increases (up to 90% increase in species and 40% in abundance in some land uses). Our results suggest that efforts to understand the vulnerability of species to environmental changes should account for different types of rarity where possible. Our results also have potentially important implications for ecosystem functioning, given that rare species may play unique roles within ecosystems. Article impact statement: Rare species show stronger negative responses to anthropogenic land use than common species

Impacts of the global food system on terrestrial biodiversity from land use and climate change

The global food system is a key driver of land-use and climate change which in turn drive biodiversity change. Developing sustainable food systems is therefore critical to reversing biodiversity loss. We use the multi-regional input-output model EXIOBASE to estimate the biodiversity impacts embedded within the global food system in 2011. Using models that capture regional variation in the sensitivity of biodiversity both to land use and climate change, we calculate the land-driven and greenhouse gas-driven footprints of food using two metrics of biodiversity: local species richness and rarity-weighted species richness. We show that the footprint of land area underestimates biodiversity impact in more species-rich regions and that our metric of rarity-weighted richness places a greater emphasis on biodiversity costs in Central and South America. We find that methane emissions are responsible for 70% of the overall greenhouse gas-driven biodiversity footprint and that, in several regions, emissions from a single year's food production are associated with global biodiversity loss equivalent to 2% or more of that region's total land-driven biodiversity loss. The measures we present are relatively simple to calculate and could be incorporated into decision-making and environmental impact assessments by governments and businesses

Bladder cancer and occupational exposures

A hospital-based cas-referent study was carried out in Lyon with the purpose of generating hypotheses about the role of occupational exposures to 320 compounds in bladder carcinogenesis. Job histories were obtained by questionnaire for 116 cases and 232 reference patients with diseases other than cancer (one referent from the same hospital ward and one from another ward of the same hospital per case) ; the referents were matched for gender, hospital, age, and nationality. Systematic coding of exposures, with a blind analysis of job histories, was carried out by a team of experts in chemistry and occupational health. Significantly elevated odds ratios were observed for exposure to pyrolysis and combustion products [odds ratio (OR) 2.3, 95 % confidence interval (95 % CI) 1.0-4.0] when the general referents were used and for cutting fluids (OR 2.6, 95 % CI 1.2-5.4) when tobacco consumption was adjusted for. The latter was highest among the category consisting of blue-collar and unskilled workers, supervisors, and agricultural workers (OR 4.6, 95 % CI 2.0-10.6), while the odds ratio for the other category was 0.8 (95 % CI 0.3-2.7). An elevated odds ratio for exposure to inks was observed for the women (OR 14.0, 95 % CI 1.8-106.5) on the basis of 14 exposed cases, but confounding factors could have been responsible for this result. Odds ratios for several other exposures (rubber : OR 5.7, nitrates : OR 8.2, coke dust : OR 3.5, meat additives : OR 3.8) were also elevated, but not significantly so when based on a small number of exposed cases. The observations of this investigation should be tested in future studies, in particular since exposures to agents such as cutting fluids or pyrolysis products are ubiquitous in industrial settings and may present an important public health hazard. (Résumé d'auteur

Burden of visceral leishmaniasis in villages of eastern gedaref state, Sudan: an exhaustive cross-sectional survey.

Since December 2009, Médecins Sans Frontières has diagnosed and treated patients with visceral leishmaniasis (VL) in Tabarak Allah Hospital, eastern Gedaref State, one of the main endemic foci of VL in Sudan. A survey was conducted to estimate the VL incidence in villages around Tabarak Allah

Incidence of WHO stage 3 and 4 conditions following initiation of Anti-Retroviral Therapy in resource limited settings

To determine the incidence of WHO clinical stage 3 and 4 conditions during early anti-retroviral therapy (ART) in resource limited settings (RLS)