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Habitat management is a form of conservation biological control that includes strategies such as the provision of alternative prey for natural enemies. One example is the banker plants strategy which consists of introducing cereals with aphids in horticultural crops. It is usually combined with parasitoid releases. In this work we evaluated whether aphid-infested barley as banker plants enhances native populations of aphidophagous syrphids and extends the residence time of Episyrphus balteatus following release. The work was performed in four replicated sweet-pepper commercial greenhouses in the southeast of Spain. Barley was sown, and infested with the aphid Rhopalosiphum maidis. Visual censuses were performed to record released individuals of E. balteatus (marked on the thorax before release) and naturally occurring hoverflies. At the end of the experiment leaf samples were taken to the laboratory, and the immature syrphids were reared for identification. The occurrence of syrphids that come from outside the greenhouse was significantly increased by the presence of the infested barley plants. From a total of 506 observations of adult native syrphids, 81% were Sphaerophoria rueppellii. We did not find significant differences between control plots and those provided with banker plants in their probabilities to retain released specimens of E. balteatus. Of the syrphids collected at immature stages from the barley leaves, we did not record any E. balteatus, and 100% of the specimens were identified as S. rueppellii. We conclude that the banker plant strategy is effective in attracting natural populations of syrphids into sweet pepper greenhouses, but not in keeping released individuals of E. balteatus in the greenhouses long enough to lay eggs. We suggest that the E. balteatus release method should be amended.

The effects of site conditions and thermal energy input on soil water repellency of dune-sand soils of the Borská nížina lowland (SW Slovakia) were evaluated. Composition of plant cover at three locations reflects soil genesis and moisture regimes. In investigated soil profiles, the severity of water repellency depends strongly on moisture regime of soils. The maximum Water Drop Penetration Time (WDPT) values exceeded 12 h in Dystric Regosol. In Arenic Umbrisol WDPT values did not exceed 60 s and Haplic Gleysol was wettable. Potential effect of wildfires on water repellency of the soils was investigated through laboratory experiments. Distinct increases in the persistence of water repellency were observed when the samples were heated for 20 minutes with maximas of WDPT observed at 150 and 200 degree C. Water repellency disappeared after heating to 250 and 300 degree C in the subsurface and topsoil horizons, respectively, due to organic matter decomposition. But it was necessary to repeat heating to 250 and 300 degree C in order to eliminate water repellency in A horizons of selected soils.

1.Disentangling the interplay between species-specific environmental preferences and micro- and macroscale determinants of species abundance within plant com-munities remains challenging. Most existing studies addressing this issue either lack empirical data regarding species interactions and local abundances or cover a narrow range of environmental conditions.2.We merged species distribution models and local spatial patterns to investigate the relative importance of key macro- (aridity) and micro(facilitation and competi-tion)scale determinants of plant species abundance along aridity gradients in dry-lands world-wide. We used information derived from the environmental niches of species to evaluate how species-specific aridity preferences modulate the impor-tance of such factors to drive species relative abundance.3.Facilitation and aridity preferences were more important than competition to ex-plain species local abundances in global drylands. The specialization of communi-ties (i.e. their compositional shifts from species with a large range of aridity preferences towards only aridity specialists) also modulated the effect of aridity and plant–plant interactions on species abundances. The importance of facilita-tion to drive species abundances decreased with aridity, as species preferred arid conditions and did not need neighbours to thrive. Instead, competition showed stronger relationships with species abundances under high levels of aridity. As composition became dominated by aridity specialists, the importance of aridity in shaping dryland plant communities did not increase further from moderate to high aridity levels.4.Synthesis. Our results showed that: (a) the degree of community specialization to aridity mediates the relative importance of plant–plant interactions in determining species abundances and (b) facilitation and competition were more strongly re-lated to species abundance in communities dominated by generalists and special-ists, respectively. We observed a shift from facilitation to competition as drivers of species abundances as aridity increases in global drylands. Our findings also pave the way to develop more robust predictions about the consequences of on-going climate change on the assemblage of plant communities in drylands, the largest terrestrial biome.

Despite their extent and socio-ecological importance, a comprehensive biogeographical synthesis of drylands is lacking. Here we synthesize the biogeography of key organisms (vascular and non-vascular vegetation and soil microorganisms), attributes (functional traits, spatial patterns, plant-plant and plant-soil interactions) and processes (productivity and land cover) across global drylands. These areas have a long evolutionary history, are centers of diversification for many plant lineages and include important plant diversity hotspots. This diversity captures a strikingly high portion of the variation in leaf functional diversity observed globally. Part of this functional diversity is associated with the large variation in response and effect traits in the shrubs encroaching dryland grasslands. Aridity and its interplay with the traits of interacting plant species largely shapes biogeographical patterns in plant-plant and plant-soil interactions, and in plant spatial patterns. Aridity also drives the composition of biocrust communities and vegetation productivity, which shows large geographical variation. We finish our review discussing major research gaps, which include: i) studying regular vegetation spatial patterns, ii) establishing large-scale plant and biocrust field surveys assessing individual-level trait measurements, iii) knowing whether plant-plant and plant-soil interactions impacts on biodiversity are predictable and iv) assessing how elevated CO2 modulates future aridity conditions and plant productivity.

How soil microbial communities respond to precipitation seasonality change remains poorly understood, particularly for warm-humid forest ecosystems experiencing clear dry-wet cycles. We conducted a field precipitation manipulation experiment in a subtropical forest to explore the impacts of reducing dry-season rainfall but increasing wet-season rainfall on soil microbial community composition and enzyme activities. A 67% reduction of throughfall during the dry season decreased soil water content (SWC) by 17–24% ( P  < 0.05), while the addition of water during the wet season had limited impacts on SWC. The seasonal precipitation redistribution had no significant effect on the microbial biomass and enzyme activities, as well as on the community composition measured with phospholipid fatty acids (PLFAs). However, the amplicon sequencing revealed differentiated impacts on bacterial and fungal communities. The dry-season throughfall reduction increased the relative abundance of rare bacterial phyla ( Gemmatimonadetes , Armatimonadetes , and Baoacteriodetes ) that together accounted for only 1.5% of the total bacterial abundance by 15.8, 40, and 24% ( P  < 0.05), respectively. This treatment also altered the relative abundance of the two dominant fungal phyla ( Basidiomycota and Ascomycota ) that together accounted for 72.4% of the total fungal abundance. It increased the relative abundance of Basidiomycota by 27.4% while reduced that of Ascomycota by 32.6% ( P  < 0.05). Our results indicate that changes in precipitation seasonality can affect soil microbial community composition at lower taxon levels. The lack of community-level responses may be ascribed to the compositional adjustment among taxonomic groups and the confounding effects of other soil physicochemical variables such as temperature and substrate availability.

The functional traits of organisms within multispecies assemblages regulate biodiversity effects on ecosystem functioning. Yet how traits should assemble to boost multiple ecosystem functions simultaneously (multifunctionality) remains poorly explored. In a multibiome litter experiment covering most of the global variation in leaf trait spectra, we showed that three dimensions of functional diversity (dispersion, rarity, and evenness) explained up to 66% of variations in multifunctionality, although the dominant species and their traits remained an important predictor. While high dispersion impeded multifunctionality, increasing the evenness among functionally dissimilar species was a key dimension to promote higher multifunctionality and to reduce the abundance of plant pathogens. Because too-dissimilar species could have negative effects on ecosystems, our results highlight the need for not only diverse but also functionally even assemblages to promote multifunctionality. The effect of functionally rare species strongly shifted from positive to negative depending on their trait differences with the dominant species. Simultaneously managing the dispersion, evenness, and rarity in multispecies assemblages could be used to design assemblages aimed at maximizing multifunctionality independently of the biome, the identity of dominant species, or the range of trait values considered. Functional evenness and rarity offer promise to improve the management of terrestrial ecosystems and to limit plant disease risks.

Phosphorus (P) acquisition is key for plant growth. Arbuscular mycorrhizal fungi (AMF) help plants acquire P from soil. Understanding which factors drive AMF-supported nutrient uptake is essential to develop more sustainable agroecosystems. Here we collected soils from 150 cereal fields and 60 non-cropped grassland sites across a 3,000 km trans-European gradient. In a greenhouse experiment, we tested the ability of AMF in these soils to forage for the radioisotope 33 P from a hyphal compartment. AMF communities in grassland soils were much more efficient in acquiring 33 P and transferred 64% more 33 P to plants compared with AMF in cropland soils. Fungicide application best explained hyphal 33 P transfer in cropland soils. The use of fungicides and subsequent decline in AMF richness in croplands reduced 33 P uptake by 43%. Our results suggest that land-use intensity and fungicide use are major deterrents to the functioning and natural nutrient uptake capacity of AMF in agroecosystems. Combining field data and greenhouse experiments, the authors show how agricultural management practices like fungicide applications can affect the degree to which arbuscular mycorrhizal fungi in the soil provision phosphorus to plants.

Validated physical activity (PA) questionnaires are crucial for collecting information in large epidemiological studies during childhood. Thus, this study analyzed the validity of a parent-reported PA questionnaire based on the Children’s Leisure Activities Study Survey by accelerometry in European children aged from 6 to 12 years old. We used data from 230 children of the Human Early-Life Exposome and Infancia y Medio Ambiente projects. Mean differences between moderate-to-vigorous PA (MVPA) reported by the questionnaire and the accelerometer were calculated (min/day), and its associated factors were explored by multiple robust linear regression. The agreement between methods was examined using a Bland–Altman plot. The concurrent validity of assessing MVPA was analyzed by cohort-adjusted Spearman’s partial correlations. ROC curve analysis was also used to explore the questionnaire’s capability to identify active children based on the World Health Organization guidelines. A moderate correlation was found between parent-reported and accelerometer MVPA (rho = 0.41, p < 0.001). The child’s sex (girl) was statistically associated with the mean MVPA difference between methods. However, this questionnaire accurately identified physically active children (area under the curve = 83.8% and 82.7% for boys and girls, cut-points = 68.6 and 45.4 min/day in MVPA, respectively). Consequently, this questionnaire is suitable for classifying active children in order to monitor public health interventions regarding PA.

Despite the rapid and dynamic evolution of research into dietary polyphenols, there is still a knowledge gap regarding their bioaccessibility since it could be influenced by the chemical and nutritional compositions of the food matrix. This study aimed to describe the impact of food thickeners (xanthan gum, guar gum, β-glucan, pectin) on the bioactivity of flavonoids from saffron floral by-products in model beverages before and after thermal processing. The different beverage formulas were characterized in terms of polyphenolic composition using HPLC-DAD-ESI-MSn and rheological properties. The impact of food thickeners and thermal processing on the inhibition of digestive enzymes was also determined. The model beverages mainly presented glycosylated flavonols (of kaempferol, quercetin, and isorhamnetin), with a reduced content in some heat-treated samples. The inhibitory effect on α-amylase was only detected in heat-treated beverages, showing the formulation without any thickener to have the greatest inhibitory effect. Finally, the presence of saffron floral by-products in the beverages showed a tendency to decrease the flow consistency index (K) and an increase in the flow behavior index (n), most probably driven by the aggregation of phenolics with thickeners. Therefore, this research provides new insights into the development of flavonoid-rich beverages in order to ensure that they exert the expected beneficial effects after their ingestion.

CO$_2$ exchange between terrestrial ecosystems and the atmosphere is key to understanding the feedbacks between climate change and the land surface. In regions with carbonaceous parent material, CO$_2$ exchange patterns occur that cannot be explained by biological processes, such as disproportionate outgassing during the daytime or night-time CO$_2$ uptake during periods when all vegetation is senescent. Neither of these phenomena can be attributed to carbonate weathering reactions, since their CO$_2$ exchange rates are too small. Soil ventilation induced by high atmospheric turbulence is found to explain atypical CO$_2$ exchange between carbonaceous systems and the atmosphere. However, by strongly altering subsurface CO2 concentrations, ventilation can be expected to influence carbonate weathering rates. By imposing ventilation-driven CO$_2$ outgassing in a carbonate weathering model, we show here that carbonate geochemistry is accelerated and does play a surprisingly large role in the observed CO$_2$ exchange pattern of a semi-arid ecosystem. We found that by rapidly depleting soil CO$_2$2 during the daytime, ventilation disturbs soil carbonate equilibria and therefore strongly magnifies daytime carbonate precipitation and associated CO$_2$ production. At night, ventilation ceases and the depleted CO$_2$ concentrations increase steadily. Dissolution of carbonate is now enhanced, which consumes CO$_2$ and largely compensates for the enhanced daytime carbonate precipitation. This is why only a relatively small effect on global carbonate weathering rates is to be expected. On the short term, however, ventilation has a drastic effect on synoptic carbonate weathering rates, resulting in a pronounced diel pattern that exacerbates the non-biological behavior of soil-atmosphere CO$_2$ exchanges in dry regions with carbonate soils.