Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.

Effects of Natura 2000 on nontarget bird and butterfly species based on citizen science data

The European Union's Natura 2000 (N2000) is among the largest international networks of protected areas. One of its aims is to secure the status of a predetermined set of (targeted) bird and butterfly species. However, nontarget species may also benefit from N2000. We evaluated how the terrestrial component of this network affects the abundance of nontargeted, more common bird and butterfly species based on data from long-term volunteer-based monitoring programs in 9602 sites for birds and 2001 sites for butterflies. In almost half of the 155 bird species assessed, and particularly among woodland specialists, abundance increased (slope estimates ranged from 0.101 [SD 0.042] to 3.51 [SD 1.30]) as the proportion of landscape covered by N2000 sites increased. This positive relationship existed for 27 of the 104 butterfly species (estimates ranged from 0.382 [SD 0.163] to 4.28 [SD 0.768]), although most butterflies were generalists. For most species, when land-cover covariates were accounted for these positive relationships were not evident, meaning land cover may be a determinant of positive effects of the N2000 network. The increase in abundance as N2000 coverage increased correlated with the specialization index for birds, but not for butterflies. Although the N2000 network supports high abundance of a large spectrum of species, the low number of specialist butterflies with a positive association with the N2000 network shows the need to improve the habitat quality of N2000 sites that could harbor open-land butterfly specialists. For a better understanding of the processes involved, we advocate for standardized collection of data at N2000 sites.

Increasing atmospheric CO2 concentrations correlate with declining nutritional status of European forests

The drivers of global change, including increases in atmospheric CO₂ concentrations, N and S deposition, and climate change, likely affect the nutritional status of forests. Here we show forest foliar concentrations of N, P, K, S and Mg decreased significantly in Europe by 5%, 11%, 8%, 6% and 7%, respectively during the last three decades. The decrease in nutritional status was especially large in Mediterranean and temperate forests. Increasing atmospheric CO₂ concentration was well correlated with the decreases in N, P, K, Mg, S concentrations and the increase of N:P ratio. Regional analyses indicated that increases in some foliar nutrient concentrations such as N, S and Ca in northern Europe occurred associated with increasingly favourable conditions of mean annual precipitation and temperature. Crucial changes in forest health, structure, functioning and services, including negative feedbacks on C capture can be expected if these trends are not reversed.

Regime shifts of Mediterranean forest carbon uptake and reduced resilience driven by multidecadal ocean surface temperatures

The mechanisms translating global circulation changes into rapid abrupt shifts in forest carbon capture in semi-arid biomes remain poorly understood. Here, we report unprecedented multidecadal shifts in forest carbon uptake in semi-arid Mediterranean pine forests in Spain over 1950-2012. The averaged carbon sink reduction varies between 31% and 37%, and reaches values in the range of 50% in the most affected forest stands. Regime shifts in forest carbon uptake are associated with climatic early warning signals, decreased forest regional synchrony and reduced long-term carbon sink resilience. We identify the mechanisms linked to ocean multidecadal variability that shape regime shifts in carbon capture. First, we show that low-frequency variations of the surface temperature of the Atlantic Ocean induce shifts in the non-stationary effects of El Niño Southern Oscillation (ENSO) on regional forest carbon capture. Modelling evidence supports that the non-stationary effects of ENSO can be propagated from tropical areas to semi-arid Mediterranean biomes through atmospheric wave trains. Second, decadal changes in the Atlantic Multidecadal Oscillation (AMO) significantly alter sea-air heat exchanges, modifying in turn ocean vapour transport over land and land surface temperatures, and promoting sustained drought conditions in spring and summer that reduce forest carbon uptake. Third, we show that lagged effects of AMO on the winter North Atlantic Oscillation also contribute to the maintenance of long-term droughts. Finally, we show that the reported strong, negative effects of ocean surface temperature (AMO) on forest carbon uptake in the last decades are unprecedented over the last 150 years. Our results provide new, unreported explanations for carbon uptake shifts in these drought-prone forests and review the expected impacts of global warming on the profiled mechanisms.

Global biodiversity, stoichiometry and ecosystem function responses to human-induced C-N-P imbalances

Global change analyses usually consider biodiversity as a global asset that needs to be preserved. Biodiversity is frequently analysed mainly as a response variable affected by diverse environmental drivers. However, recent studies highlight that gradients of biodiversity are associated with gradual changes in the distribution of key dominant functional groups characterized by distinctive traits and stoichiometry, which in turn often define the rates of ecosystem processes and nutrient cycling. Moreover, pervasive links have been reported between biodiversity, food web structure, ecosystem function and species stoichiometry. Here we review current global stoichiometric gradients and how future distributional shifts in key functional groups may in turn influence basic ecosystem functions (production, nutrient cycling, decomposition) and therefore could exert a feedback effect on stoichiometric gradients. The C-N-P stoichiometry of most primary producers (phytoplankton, algae, plants) has been linked to functional trait continua (i.e. to major axes of phenotypic variation observed in inter-specific analyses of multiple traits). In contrast, the C-N-P stoichiometry of higher-level consumers remains less precisely quantified in many taxonomic groups. We show that significant links are observed between trait continua across trophic levels. In spite of recent advances, the future reciprocal feedbacks between key functional groups, biodiversity and ecosystem functions remain largely uncertain. The reported evidence, however, highlights the key role of stoichiometric traits and suggests the need of a progressive shift towards an ecosystemic and stoichiometric perspective in global biodiversity analyses.

Contrasting trait syndromes in angiosperms and conifers are associated with different responses of tree growth to temperature on a large scale

Recent large-scale studies of tree growth in the Iberian Peninsula reported contrasting positive and negative effects of temperature in Mediterranean angiosperms and conifers. Here we review the different hypotheses that may explain these trends and propose that the observed contrasting responses of tree growth to temperature in this region could be associated with a continuum of trait differences between angiosperms and conifers. Angiosperm and conifer trees differ in the effects of phenology in their productivity, in their growth allometry, and in their sensitivity to competition. Moreover, angiosperms and conifers significantly differ in hydraulic safety margins, sensitivity of stomatal conductance to vapor-pressure deficit (VPD), xylem recovery capacity or the rate of carbon transfer. These differences could be explained by key features of the xylem such as non-structural carbohydrate content (NSC), wood parenchymal fraction or wood capacitance. We suggest that the reviewed trait differences define two contrasting ecophysiological strategies that may determine qualitatively different growth responses to increased temperature and drought. Improved reciprocal common garden experiments along altitudinal or latitudinal gradients would be key to quantify the relative importance of the different hypotheses reviewed. Finally, we show that warming impacts in this area occur in an ecological context characterized by the advance of forest succession and increased dominance of angiosperm trees over extensive areas. In this context, we examined the empirical relationships between the responses of tree growth to temperature and hydraulic safety margins in angiosperm and coniferous trees. Our findings suggest a future scenario in Mediterranean forests characterized by contrasting demographic responses in conifer and angiosperm trees to both temperature and forest succession, with increased dominance of angiosperm trees, and particularly negative impacts in pines.

Evidence of current impact of climate change on life: a walk from genes to the biosphere

We review the evidence of how organisms and populations are currently responding to climate change through phenotypic plasticity, genotypic evolution, changes in distribution and, in some cases, local extinction. Organisms alter their gene expression and metabolism to increase the concentrations of several antistress compounds and to change their physiology, phenology, growth and reproduction in response to climate change. Rapid adaptation and microevolution occur at the population level. Together with these phenotypic and genotypic adaptations, the movement of organisms and the turnover of populations can lead to migration toward habitats with better conditions unless hindered by barriers. Both migration and local extinction of populations have occurred. However, many unknowns for all these processes remain. The roles of phenotypic plasticity and genotypic evolution and their possible trade-offs and links with population structure warrant further research. The application of omic techniques to ecological studies will greatly favor this research. It remains poorly understood how climate change will result in asymmetrical responses of species and how it will interact with other increasing global impacts, such as N eutrophication, changes in environmental N : P ratios and species invasion, among many others. The biogeochemical and biophysical feedbacks on climate of all these changes in vegetation are also poorly understood. We here review the evidence of responses to climate change and discuss the perspectives for increasing our knowledge of the interactions between climate change and life.

Biogeography of species richness gradients: linking adaptive traits, demography and diversification

Here we review how adaptive traits contribute to the emergence and maintenance of species richness gradients through their influence on demographic and diversification processes. We start by reviewing how demographic dynamics change along species richness gradients. Empirical studies show that geographical clines in population parameters and measures of demographic variability are frequent along latitudinal and altitudinal gradients. Demographic variability often increases at the extremes of regional species richness gradients and contributes to shape these gradients. Available studies suggest that adaptive traits significantly influence demographic dynamics, and set the limits of species distributions. Traits related to thermal tolerance, resource use, phenology and dispersal seem to play a significant role. For many traits affecting demography and/or diversification processes, complex mechanistic approaches linking genotype, phenotype and fitness are becoming progressively available. In several taxa, species can be distributed along adaptive trait continuums, i.e. a main axis accounting for the bulk of inter-specific variation in some correlated adaptive traits. It is shown that adaptive trait continuums can provide useful mechanistic frameworks to explain demographic dynamics and diversification in species richness gradients. Finally, we review the existence of sequences of adaptive traits in phylogenies, the interactions of adaptive traits and community context, the clinal variation of traits across geographical gradients, and the role of adaptive traits in determining the history of dispersal and diversification of clades. Overall, we show that the study of demographic and evolutionary mechanisms that shape species richness gradients clearly requires the explicit consideration of adaptive traits. To conclude, future research lines and trends in the field are briefly outlined.

Prevalence of coeliac disease in Down's syndrome

OBJECTIVE

During the past decade, it has been shown that the association between Down's syndrome and coeliac disease is relatively frequent Prevalence rates of coeliac disease in patients with Down's syndrome reported by different authors are significantly higher than those found in the general population. The main purpose of this study was to assess the prevalence of coeliac disease in a series of subjects with Down's syndrome from our geographical area.

DESIGN

A cross-sectional study.

SETTING

Outpatient paediatric clinics of acute-care teaching hospitals in Barcelona, Spain.

PARTICIPANTS

A total of 284 persons with Down's syndrome aged between 1 and 25 years were included in the study. In all cases, serum concentrations of antigliadin antibodies (AGAs) (Pharmacia CAP system enzyme-linked immunosorbent assay), antiendomysium antibodies (AEA) (indirect immunofluorescence) of immunoglobulin (Ig)A class or IgG class in cases of IgA deficiency were determined. Jejunal biopsy was offered to all patients with AEA positivity and to those with suggestive clinical manifestations of coeliac disease. In all patients, a clinical study was made to evaluate the presence and time-course of symptoms related to coeliac disease.

MAIN OUTCOME MEASURES AND RESULTS

In 18 of the 284 subjects with Down's syndrome, aged between 2 and 15 years, coeliac disease was confirmed by jejunal biopsy. Accordingly, the minimum prevalence rate of coeliac disease was of 6.3%. Ninety-four percent (17/18) and 78% (14/18) of patients with the association Down's syndrome and coeliac disease showed AEA and AGA positivity, respectively. Fifteen patients with the association coeliac disease and Down's syndrome (15/18) showed clinical manifestations compatible with coeliac disease, with a predominance of intestinal symptoms (8/18) over those with atypical or extra-intestinal forms (7/18). Three patients had clinically silent forms of coeliac disease (3/ 18).

CONCLUSIONS

Measurement of serum concentrations of AEA should be added to the list of screening tests for coeliac disease in patients with Down's syndrome, otherwise definite association between both diseases may pass unnoticed and diagnosis of coeliac disease be considerably delayed.

Serological markers and HLA-DQ2 haplotype among first-degree relatives of celiac patients. Catalonian Coeliac Disease Study Group

Serologic markers, HLA-DQ2 haplotype, and clinical features suggestive of celiac disease were studied to assess their diagnostic value in a multicentric study to detect celiac disease in 675 first-degree relatives of 227 celiac probands. Serum IgA-class anti-endomysium and IgA-class anti-gliadin antibodies were positive in 5.8% and 1.9% of relatives, respectively. HLA-DQ2 haplotype was present in 64% of relatives, and the overall rate of celiac disease diagnosed by intestinal biopsy was 5.5%. The frequency of HLA-DQ2 in the celiac patients and controls was 93% and 18%, respectively. The most frequent clinical features--diarrhea, anemia, food intolerance, and growth retardation--were not present in one third of the celiac disease relatives. We conclude that the assessment of IgA-class anti-endomysium antibodies alone seems a reasonable approach for screening celiac disease in relatives and cannot be replaced by an accurate clinical anamnesis. HLA-DQ2 haplotype may identify the population with a high genetic susceptibility to celiac disease.

Serological markers and HLA-DQ2 haplotype among first-degree relatives of celiac patients. Catalonian Coeliac Disease Study Group

Serologic markers, HLA-DQ2 haplotype, and clinical features suggestive of celiac disease were studied to assess their diagnostic value in a multicentric study to detect celiac disease in 675 first-degree relatives of 227 celiac probands. Serum IgA-class anti-endomysium and IgA-class anti-gliadin antibodies were positive in 5.8% and 1.9% of relatives, respectively. HLA-DQ2 haplotype was present in 64% of relatives, and the overall rate of celiac disease diagnosed by intestinal biopsy was 5.5%. The frequency of HLA-DQ2 in the celiac patients and controls was 93% and 18%, respectively. The most frequent clinical features--diarrhea, anemia, food intolerance, and growth retardation--were not present in one third of the celiac disease relatives. We conclude that the assessment of IgA-class anti-endomysium antibodies alone seems a reasonable approach for screening celiac disease in relatives and cannot be replaced by an accurate clinical anamnesis. HLA-DQ2 haplotype may identify the population with a high genetic susceptibility to celiac disease.

Treatment of chronic hepatitis B in children with recombinant alfa interferon. Different response according to age at infection

The objective of this study was to investigate the possibility of predictive factors of response to treatment with interferon in children with chronic hepatitis B virus infection. We analyzed the influence on the response rate of age, sex, mode of acquisition of infection, severity, and duration of disease in 16 children with chronic hepatitis B treated with 3 MU of recombinant alpha-interferon 2b three times a week for 6 months. Six months after the end of treatment, eight patients (50%) had cleared HBV DNA, seroconverted to anti-HBe and normalized serum transaminase values. Response was significantly higher in those whose serum transaminase levels were > 100 IU/liter before treatment (70%) and those infected after birth (72%) compared with those with lower serum transaminase levels (16%) and those infected at birth (7%). Our findings indicate that a 6 month course of low dose interferon (3 MU) is highly effective in children with horizontally transmitted chronic hepatitis B virus infection, but noneffective in children infected at birth.

[Diagnosis of hypertrophic stenosis of the pylorus by ultrasonography]

Ten infants with a clinical history of hypertrophic pyloric stenosis were examined sonographically. Upper gastrointestinal series were also performed on these patients. The authors comment on the findings, and the value of ultrasound examination in the diagnosis of hypertrophic pyloric stenosis.

[Neonatal intrahepatic cholestasis and alpha-1-antitrypsin deficiency (author's transl)]

A case of alpha-1-antitrypsin deficiency in an 11 month-old Pi ZZ infant is reported. The patient exhibited intrahepatic cholestasis in the first months of life, with jaundice and hepatomegaly. Liver biopsy confirmed the diagnosis and showed the presence of hepatic fibrosis. Pi phenotypes, serum levels of alpha-1-antitrypsin, and symptoms in the family of the patient are reported. Clinical, biochemical and pathologic findings in liver disease in alpha-1-antitrypsin deficiency are discussed.