Photoautotrophic soil cyanobacteria play essential ecological roles and are known to exhibit large changes in their diversity and abundance throughout early succession. However, much less is known about how and why soil cyanobacterial communities change as soil develops over centuries and millennia, and the effects that vegetation have on such communities.
We combined an extensive field survey, including 16 global soil chronosequences across contrasting ecosystems (from deserts to tropical forests), with molecular analyses to investigate how the diversity and abundance of photosynthetic and nonphotosynthetic soil cyanobacteria are affected by vegetation change during soil development, over time periods from hundreds to thousands of years.
We show that, in most chronosequences, the abundance, species richness and community composition of soil cyanobacteria are relatively stable as soil develops (from centuries to millennia). Regardless of soil age, forest chronosequences were consistently dominated by nonphotosynthetic cyanobacteria (Vampirovibrionia), while grasslands and shrublands were dominated by photosynthetic cyanobacteria. Chronosequences undergoing drastic vegetation shifts (e.g. transitions from grasslands to forests) experienced significant changes in the composition of soil cyanobacterial communities.
Our results advance our understanding of the ecology of cyanobacterial classes, and of the understudied nonphotosynthetic cyanobacteria in particular, and highlight the key role of vegetation as a major driver of their temporal dynamics as soil develops.
Network analysis has been used for many years in ecological research to analyze organismal associations, for example in food webs, plant-plant or plant-animal interactions. Although network analysis is widely applied in microbial ecology, only recently has it entered the realms of soil microbial ecology, shown by a rapid rise in studies applying co-occurrence analysis to soil microbial communities. While this application offers great potential for deeper insights into the ecological structure of soil microbial ecosystems, it also brings new challenges related to the specific characteristics of soil datasets and the type of ecological questions that can be addressed. In this Perspectives Paper we assess the challenges of applying network analysis to soil microbial ecology due to the small-scale heterogeneity of the soil environment and the nature of soil microbial datasets. We review the different approaches of network construction that are commonly applied to soil microbial datasets and discuss their features and limitations. Using a test dataset of microbial communities from two depths of a forest soil, we demonstrate how different experimental designs and network constructing algorithms affect the structure of the resulting networks, and how this in turn may influence ecological conclusions. We will also reveal how assumptions of the construction method, methods of preparing the dataset, and definitions of thresholds affect the network structure. Finally, we discuss the particular questions in soil microbial ecology that can be approached by analyzing and interpreting specific network properties. Targeting these network properties in a meaningful way will allow applying this technique not in merely descriptive, but in hypothesis-driven research.Research in limnology is nurtured by the work of many fascinating and passionate women, who have contributed enormously to our understanding of inland waters. Female limnologists have promoted and established the bases of our knowledge about inland waters and fostered the need of protecting the values of those ecosystems. However, on numerous occasions, their contribution to the advancement of limnology has not been duly recognized. Here, we review the presence of women in limnology through the history of the discipline: from the pioneers who contributed to the origins to present day' developments. We aim at visibilizing those scientists and establish them as role models. We also analyze in a simple and illustrative way the current situation of women in limnology, the scientific barriers they must deal with, and their future prospects. Multiple aspects fostering the visibility of a scientist, such as their presence in conferences, awards, or representation in societal or editorial boards show a significant gap, with none of those aspects showing a similar visibility of women and men in limnology. This article raises awareness of the obstacles that women in limnology faced and still face, and encourages to embrace models of leadership, scientific management, and assessment of research performance far from those commonly established.This article is categorized under:
Science of Water > Methods
Water and Life > Methods
Soils harbour a rich arthropod fauna, but many species are still not formally described (Linnaean shortfall) and the distribution of those already described is poorly understood (Wallacean shortfall). Metabarcoding holds much promise to fill this gap, however, nuclear copies of mitochondrial genes, and other artefacts lead to taxonomic inflation, which compromise the reliability of biodiversity inventories. Here, we explore the potential of a bioinformatic approach to jointly \uffe2\uff80\uff9cdenoise\uffe2\uff80\uff9d and filter nonauthentic mitochondrial sequences from metabarcode reads to obtain reliable soil beetle inventories and address open questions in soil biodiversity research, such as the scale of dispersal constraints in different soil layers. We sampled cloud forest arthropod communities from 49 sites in the Anaga peninsula of Tenerife (Canary Islands). We performed whole organism community DNA (wocDNA) metabarcoding, and built a local reference database with COI barcode sequences of 310 species of Coleoptera for filtering reads and the identification of metabarcoded species. This resulted in reliable haplotype data after considerably reducing nuclear mitochondrial copies and other artefacts. Comparing our results with previous beetle inventories, we found: (i) new species records, potentially representing undescribed species; (ii) new distribution records, and (iii) validated phylogeographic structure when compared with traditional sequencing approaches. Analyses also revealed evidence for higher dispersal constraint within deeper soil beetle communities, compared to those closer to the surface. The combined power of barcoding and metabarcoding contribute to mitigate the important shortfalls associated with soil arthropod diversity data, and thus address unresolved questions for this vast biodiversity fraction.The biogeochemical cycling of multiple soil elements is fundamental for life on Earth. Here, we conducted a global field survey across 16 chronosequences from contrasting biomes with soil ages ranging from centuries to millions of years. For this, we collected and analysed 435 topsoil samples (0\uffe2\uff80\uff9310\uffc2\uffa0cm) from 87 locations. We showed that high levels of topsoil element coupling, defined as the average correlation among nineteen soil elements, are maintained over geological timescales globally. Cross\uffe2\uff80\uff90biome changes in plant biodiversity, soil microbial structure, weathering, soil pH and texture, and mineral\uffe2\uff80\uff90free unprotected organic matter content largely controlled multi\uffe2\uff80\uff90element coupling. Moreover, elements with heavier atomic mass were naturally more decoupled and unpredictable in space than those with lighter mass. Only the coupling of carbon, nitrogen and phosphorus, which are essential to life on Earth, deviated from this predictable pattern, suggesting that this anomaly may be an undeniable fingerprint of life in terrestrial soils.Under controlled laboratory conditions, high and low ammonium availability are known to favor soil ammonia-oxidizing bacteria (AOB) and archaea (AOA) communities, respectively. However, whether this niche segregation is maintained under field conditions in terrestrial ecosystems remains unresolved, particularly at the global scale. We hypothesized that perennial vegetation might favor AOB vs. AOA communities compared with adjacent open areas devoid of perennial vegetation (i.e., bare soil) via several mechanisms, including increasing the amount of ammonium in soil. To test this niche-differentiation hypothesis, we conducted a global field survey including 80 drylands from 6 continents. Data supported our hypothesis, as soils collected under plant canopies had higher levels of ammonium, as well as higher richness (number of terminal restriction fragments; T-RFs) and abundance (qPCR amoA genes) of AOB, and lower richness and abundance of AOA, than those collected in open areas located between plant canopies. Some of the reported associations between plant canopies and AOA and AOB communities can be a consequence of the higher organic matter and available N contents found under plant canopies. Other aspects of soils associated with vegetation including shading and microclimatic conditions might also help explain our results. Our findings provide strong evidence for niche differentiation between AOA and AOB communities in drylands worldwide, advancing our understanding of their ecology and biogeography at the global scale.Calcium biomineralisation is widely documented in plants. However, crystallisation of Ca\uffe2\uff80\uff90sulphate\uffe2\uff80\uff90containing minerals is closely related to water content, and sample processing, such as drying, alters the water balance of plant tissues. We hypothesised that common sample processing practices may favour the formation of crystals, leading to spurious crystallisation not observed in unaltered plant tissues. We selected three species (Ononis tridentata, Helianthemum squamatum and Gypsophila struthium) with reported gypsum biomineralisation. We used x\uffe2\uff80\uff90ray diffractometry on fresh intact or sliced leaves, and on the same leaves processed by subsequent drying, to address whether sample processing alters crystal formation. Ca\uffe2\uff80\uff90sulphate crystals were detected in dry samples of all species but not in fresh intact samples. Ca\uffe2\uff80\uff90sulphate crystallisation occurred in some cut fresh samples, although the accumulation greatly increased after drying. In addition, G. struthium exhibited Ca\uffe2\uff80\uff90oxalate crystals in both fresh and dry treatments, with a tendency for greater accumulation in dry treatments. Our results demonstrate that the Ca\uffe2\uff80\uff90sulphate crystals observed by x\uffe2\uff80\uff90ray diffractometry in these species are artefacts caused by common sample processing practices, such as excessive drying and slicing samples. We encourage future studies on the biomineral potential of plants to avoid the use of procedures that alter the water balance of tissues.Biotic interactions are highly affected by species traits and micro\uffe2\uff80\uff90environmental variability. Research on facilitation has primarily focused on how nurse species alleviate abiotic stress for beneficiary species, while the impact of the micro\uffe2\uff80\uff90environmental variability generated by nurse plants in shaping facilitation outcomes is poorly understood. This study has two objectives: (i) To evaluate which traits define beneficiary species and (ii) to evaluate whether nurse and non\uffe2\uff80\uff90nurse species differ in their ability to reduce abiotic stress and its variability under their canopy.
We sampled recruits in two arid and stressful environments to assess (i) which species accumulate more juveniles beneath their canopy controlling for their coverage (nurse vs. non\uffe2\uff80\uff90nurse species) and (ii) which species benefited from facilitation by determining whether they tend to recruit more beneath other species or on the bare ground (beneficiary/non\uffe2\uff80\uff90beneficiary). First, we compared how nurse and non\uffe2\uff80\uff90nurse species modify the physical and chemical microenvironments underneath their canopy, both in terms of magnitude and variation. Second, we compared root growth, water retention and nutrient accumulation in juvenile plants of beneficiary and non\uffe2\uff80\uff90beneficiary species.
We found that facilitation is enhanced by species that provide a more homogeneous microenvironment rather than an intense reduction of microenvironmental stress under their canopy. In addition, the juveniles of beneficiary species invest more in root development, accumulate Ca and S in their shoot tissues, and show a higher water content than non\uffe2\uff80\uff90beneficiary species.
Our findings indicate that the homogeneity of microenvironments plays a crucial role in facilitative interactions, and the juveniles of beneficiary species show a less conservative strategy, investing more in resource acquisition than juveniles of non\uffe2\uff80\uff90beneficiary species.
Read the free Plain Language Summary for this article on the Journal blog.
Root\uffe2\uff80\uff90infecting vascular fungi cause wilt diseases and provoke devastating losses in hundreds of crops. It is currently unknown how these pathogens evolved and whether they can also infect nonvascular plants, which diverged from vascular plants over 450 million years ago.
We established a pathosystem between the nonvascular plant Marchantia polymorpha (Mp) and the root\uffe2\uff80\uff90infecting vascular wilt fungus Fusarium oxysporum (Fo). On angiosperms, Fo exhibits exquisite adaptation to the plant xylem niche as well as host\uffe2\uff80\uff90specific pathogenicity, both of which are conferred by effectors encoded on lineage\uffe2\uff80\uff90specific chromosomes.
Fo isolates displaying contrasting lifestyles on angiosperms \uffe2\uff80\uff93 pathogenic vs endophytic \uffe2\uff80\uff93 are able to infect Mp and cause tissue maceration and host cell killing. Using isogenic fungal mutants we define a set of conserved fungal pathogenicity factors, including mitogen activated protein kinases, transcriptional regulators and cell wall remodelling enzymes, that are required for infection of both vascular and nonvascular plants. Markedly, two host\uffe2\uff80\uff90specific effectors and a morphogenetic regulator, which contribute to vascular colonisation and virulence on tomato plants are dispensable on Mp.
Collectively, these findings suggest that vascular wilt fungi employ conserved infection strategies on nonvascular and vascular plant lineages but also have specific mechanisms to access the vascular niche of angiosperms.
Unprecedented nitrogen (N) inputs into terrestrial ecosystems have profoundly altered soil N cycling. Ammonia oxidizers and denitrifiers are the main producers of nitrous oxide (N2O), but it remains unclear how ammonia oxidizer and denitrifier abundances will respond to N loading and whether their responses can predict N\uffe2\uff80\uff90induced changes in soil N2O emission. By synthesizing 101 field studies worldwide, we showed that N loading significantly increased ammonia oxidizer abundance by 107% and denitrifier abundance by 45%. The increases in both ammonia oxidizer and denitrifier abundances were primarily explained by N loading form, and more specifically, organic N loading had stronger effects on their abundances than mineral N loading. Nitrogen loading increased soil N2O emission by 261%, whereas there was no clear relationship between changes in soil N2O emission and shifts in ammonia oxidizer and denitrifier abundances. Our field\uffe2\uff80\uff90based results challenge the laboratory\uffe2\uff80\uff90based hypothesis that increased ammonia oxidizer and denitrifier abundances by N loading would directly cause higher soil N2O emission. Instead, key abiotic factors (mean annual precipitation, soil pH, soil C:N ratio, and ecosystem type) explained N\uffe2\uff80\uff90induced changes in soil N2O emission. Altogether, these findings highlight the need for considering the roles of key abiotic factors in regulating soil N transformations under N loading to better understand the microbially mediated soil N2O emission.This study analyses long\uffe2\uff80\uff90term changes in drought indices (Standardised Precipitation Index\uffe2\uff80\uff94SPI, Standardised Precipitation\uffe2\uff80\uff93Evapotranspiration Index\uffe2\uff80\uff94SPEI) at 1 and 3\uffe2\uff80\uff89months scales at 182 stations in 11 central and eastern European countries during 1949\uffe2\uff80\uff932018. For comparative purposes, the necessary atmospheric evaporative demand (AED) to obtain SPEI was calculated using two methods, Hargreaves\uffe2\uff80\uff90Samani (SPEIH) and Penman\uffe2\uff80\uff90Monteith (SPEIP). The results show some relevant changes and tendencies in the drought indices. Statistically significant increase in SPI and SPEI during the cold season (November\uffe2\uff80\uff93March), reflecting precipitation increase, was found in the northern part of the study region, in Estonia, Latvia, Lithuania, northern Belarus and northern Poland. In the rest of study domain, a weak and mostly insignificant decrease prevailed in winter. Summer season (June\uffe2\uff80\uff93August) is characterized by changes in the opposite sign. An increase was observed in the north, while a clear decrease in SPEI, reflecting a drying trend, was typical for the southern regions: the Czech Republic, Slovakia, Hungary, Romania, Moldova and southern Poland. A general drying tendency revealed also in April, which was statistically significant over a wide area in the Czech Republic and Poland. Increasing trends in SPI and SPEI for September and October were detected in Romania, Moldova and Hungary. The use of SPEI instead of SPI generally enhances drying trends.Herbivory and extreme soils are drivers of plant evolution. Adaptation to extreme soils often implies substrate-specific traits, and resistance to herbivory involves tolerance or avoidance mechanisms. However, little research has been done on the effect of grazing on plant communities rich in edaphic endemics growing on extreme soils. A widespread study case is gypsum drylands, where livestock grazing often prevails. Despite their limiting conditions, gypsum soils host a unique and highly specialised flora, identified as a conservation priority. MethodsWe evaluated the effect of different grazing intensities on the assembly of perennial plant communities growing on gypsum soils. We considered the contribution of species gypsum affinity and key functional traits of species such as traits related to gypsum specialisation (leaf S accumulation) or traits related to plant tolerance to herbivory such as leaf C and N concentrations. The effect of grazing intensity on plant community indices ( i.e. , richness, diversity, community weighted-means (CWM) and functional diversity (FD) indices for each trait) were modelled using Generalised Linear Mixed Models (GLMM). We analysed the relative contribution of interspecific trait variation and intraspecific trait variation (ITV) in shifts of community index values.
ResultsLivestock grazing may benefit gypsum plant specialists during community assembly, as species with high gypsum affinity, and high leaf S contents, were more likely to assemble in the most grazed plots. Grazing also promoted species with traits related to herbivory tolerance, as species with a rapid-growth strategy (high leaf N, low leaf C) were promoted under high grazing conditions. Species that ultimately formed gypsum plant communities had sufficient functional variability among individuals to cope with different grazing intensities, as intraspecific variability was the main component of species assembly for CWM values.
ConclusionsThe positive effects of grazing on plant communities in gypsum soils indicate that livestock may be a key tool for the conservation of these edaphic endemics.
", "keywords": ["2. Zero hunger", "0106 biological sciences", "Edpahism", "QH301-705.5", "Mineral nutrition", "Intraspecific variability", "R", "Gypsophily", "Functional diversity", "15. Life on land", "01 natural sciences", "Gypsovag", "Medicine", "Biology (General)", "Plant-herbivore interactions", "Gypsophile"]}, "links": [{"href": "https://peerj.com/articles/14222.pdf"}, {"href": "https://doi.org/10261/359972"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/PeerJ", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10261/359972", "name": "item", "description": "10261/359972", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10261/359972"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-10-12T00:00:00Z"}}, {"id": "10261/358708", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-03T16:26:51Z", "type": "Journal Article", "created": "2022-06-29", "title": "Gypsum endemics accumulate excess nutrients in leaves as a potential constitutive strategy to grow in grazed extreme soils", "description": "AbstractExtreme soils often have mineral nutrient imbalances compared to plant nutritional requirements and co\uffe2\uff80\uff90occur in open areas where grazers thrive. Thus, plants must respond to both constraints, which can affect nutrient concentrations in all plant organs. Gypsum soil provides an excellent model system to study adaptations to extreme soils under current grazing practices as it harbours two groups of plant species that differ in their tolerance to gypsum soils and foliar composition. However, nutrient concentrations in organs other than leaves, and their individual responses to simulated herbivory, are still unknown in gypsum plants. We studied plant biomass, root mass ratio and nutrient partitioning among different organs (leaves, stems, coarse roots, fine roots) in five gypsum endemics and five generalists cultivated in gypsum and calcareous soils and subjected to different levels of simulated browsing. Gypsum endemics tended to have higher elemental concentration in leaves, stems and coarse roots than generalist species in both soil types, whereas both groups tended to show similar high concentrations in fine roots. This behaviour was especially clear with sulphur (S), which is found in excess in gypsum soils, and which endemics accumulated in leaves as sulphate (>50% of S). Moreover, plants subjected to clipping, regardless of their affinity to gypsum, were unable to compensate for biomass losses and showed similar elemental composition to unclipped plants. The accumulation of excess mineral nutrients by endemic species in aboveground organs may be a constitutive nutritional strategy in extreme soils and is potentially playing an anti\uffe2\uff80\uff90herbivore role in grazed gypsum outcrops.
The analysis of plant elemental composition and the underlying factors affecting its variation are a current hot topic in ecology. Ecological adaptation to atypical soils may shift plant elemental composition. However, no previous studies have evaluated its relevance against other factors such as phylogeny, climate or individual soil conditions.
We evaluated the effect of the phylogeny, environment (climate, soil), and affinity to gypsum soils on the elemental composition of 83 taxa typical of Iberian gypsum ecosystems. We used a new statistical procedure (multiple phylogenetic variance decomposition, MPVD) to decompose total explained variance by different factors across all nodes in the phylogenetic tree of target species (covering 120\uffe2\uff80\uff89million\uffe2\uff80\uff89years of Angiosperm evolution).
Our results highlight the relevance of phylogeny on the elemental composition of plants both at early (with the development of key preadaptive traits) and recent divergence times (diversification of the Iberian gypsum flora concurrent with Iberian gypsum deposit accumulation). Despite the predominant phylogenetic effect, plant adaptation to gypsum soils had a strong impact on the elemental composition of plants, particularly on sulphur concentrations, while climate and soil effects were smaller.
Accordingly, we detected a convergent evolution of gypsum specialists from different lineages on increased sulphur and magnesium foliar concentrations.
Heavy metal\uffe2\uff80\uff90rich toxic soils and ordinary soils are both natural habitats of Arabidopsis halleri , a diploid perennial and obligate outcrosser in the sister clade of the genetic model plant Arabidopsis thaliana . The molecular divergence underlying survival in sharply contrasting environments is unknown. Here we comparatively address metal physiology and transcriptomes of A. halleri originating from the most highly heavy metal\uffe2\uff80\uff90contaminated soil in Europe, Ponte Nossa, Italy (Noss), and from non\uffe2\uff80\uff90metalliferous (NM) soils. Plants from Noss exhibit enhanced hypertolerance and attenuated accumulation of cadmium (Cd), and their transcriptomic Cd responsiveness is decreased, compared to plants of NM soil origin. Among the condition\uffe2\uff80\uff90independent transcriptome characteristics of Noss, the most highly overrepresented functional class of \uffe2\uff80\uff98meiotic cell cycle\uffe2\uff80\uff99 comprises 21 transcripts with elevated abundance in vegetative tissues, in particular Argonaute 9 ( AGO9 ) and the synaptonemal complex transverse filament protein\uffe2\uff80\uff90encoding ZYP1a/b . Increased AGO9 transcript levels in Noss are accompanied by decreased long terminal repeat retrotransposon expression. Similar to Noss, plants from other highly metalliferous sites in Poland and Germany share elevated somatic AGO9 transcript levels in comparison to plants originating from NM soils in their respective geographic regions. Transcript levels of Iron\uffe2\uff80\uff90Regulated Transporter 1 ( IRT1 ) are very low and transcript levels of Heavy Metal ATPase 2 ( HMA2 ) are strongly elevated in Noss, which can account for its altered Cd handling. We conclude that in plants adapted to the most extreme abiotic stress, broadly enhanced functions comprise genes with likely roles in somatic genome integrity maintenance, accompanied by few alterations in stress\uffe2\uff80\uff90specific functional networks. Enhancing the reliability of literature reviews and evidence synthesis is crucial for advancing the transformation of agriculture and food (agri-food) systems as well as for informed decisions and policy making. In this perspective, we argue that evidence syntheses in the field of agri-food systems research often suffer from a suite of methodological limitations that substantially increase the risk of bias, i.e., publication and selection bias, resulting in unreliable and potentially flawed conclusions and, consequently, poor decisions (e.g., policy direction, investment, research foci). We assessed 926 articles from the Collaboration for Environmental Evidence Database of Evidence Reviews (CEEDER) and recent examples from agri-food systems research to support our reasoning. The analysis of articles from CEEDER (n\uffe2\uff80\uff89=\uffe2\uff80\uff89926) specifically indicates poor quality (Red) in measures to minimize subjectivity during critical appraisal (98% of all reviews), application of the eligibility criteria (97%), cross-checking of extracted data by more than one reviewer (97%), critical appraisal of studies (88%), establishment of an a priori method/protocol (86%), and transparent reporting of eligibility decisions (65%). Additionally, deficiencies (Amber) were found in most articles (>50%) regarding the investigation and discussion of variability in study findings (89%), comprehensiveness of the search (78%), definition of eligibility criteria (72%), search approach (64%), reporting of extracted data for each study (59%), consideration and discussion of the limitations of the synthesis (56%), documentation of data extraction (54%) and regarding the statistical approach (52%). To enhance the quality of evidence synthesis in agri-food science, review authors should use tried-and-tested methodologies and publish peer-reviewed a priori protocols. Training in evidence synthesis methods should be scaled, with universities playing a crucial role. It is the shared duty of research authors, training providers, supervisors, reviewers, and editors to ensure that rigorous and robust evidence syntheses are made available to decision-makers. We argue that all these actors should be cognizant of these common mistakes to avoid publishing unreliable syntheses. Only by thinking as a community can we ensure that reliable evidence is provided to support appropriate decision-making in agri-food systems science.Significant rates of atmospheric dihydrogen (H2) consumption have been observed in temperate soils due to the activity of high-affinity enzymes, such as the group 1h [NiFe]-hydrogenase. We designed broadly inclusive primers targeting the large subunit gene (hhyL) of group 1h [NiFe]-hydrogenases for long-read sequencing to explore its taxonomic distribution across soils. This approach revealed a diverse collection of microorganisms harboring hhyL, including previously unknown groups and taxonomically not assignable sequences. Acidobacterial group 1h [NiFe]-hydrogenase genes were abundant and expressed in temperate soils. To support the participation of acidobacteria in H2 consumption, we studied two representative mesophilic soil acidobacteria, which expressed group 1h [NiFe]-hydrogenases and consumed atmospheric H2 during carbon starvation. This is the first time mesophilic acidobacteria, which are abundant in ubiquitous temperate soils, have been shown to oxidize H2 down to below atmospheric concentrations. As this physiology allows bacteria to survive periods of carbon starvation, it could explain the success of soil acidobacteria. With our long-read sequencing approach of group 1h [NiFe]-hydrogenase genes, we show that the ability to oxidize atmospheric levels of H2 is more widely distributed among soil bacteria than previously recognized and could represent a common mechanism enabling bacteria to persist during periods of carbon deprivation.Dissolved organic matter (DOM) composition exerts a direct control on its degradation and subsequent persistence in aquatic ecosystems. Yet, under certain conditions, the degradation patterns of DOM cannot be solely explained by its composition, highlighting the relevance of environmental conditions for DOM degradation. Here, we experimentally assessed the relative influence of composition vs. environment on DOM degradation by performing degradation bioassays using three contrasting DOM sources inoculated with a standardized bacterial inoculum under five distinct environments. The DOM degradation kinetics modeled using reactivity continuum models showed that composition was more important than environment in determining the bulk DOM decay patterns. Changes in DOM composition resulted from the interaction between DOM source and environment. The role of environment was stronger on shaping the bacterial community composition, but the intrinsic nature of the DOM source exerted stronger control on the DOM degradation function.Nutrient acquisition is crucial for sustaining life. Plants develop beneficial intracellular partnerships with arbuscular mycorrhiza (AM) and nitrogen-fixing bacteria to surmount the scarcity of soil nutrients and tap into atmospheric dinitrogen, respectively1,2. Initiation of these root endosymbioses requires symbiont-induced oscillations in nuclear calcium (Ca2+) concentrations in root cells3. How the nuclear-localized ion channels, cyclic nucleotide-gated channel (CNGC) 15 and DOESN\uffe2\uff80\uff99T MAKE INFECTIONS1 (DMI1)4 are coordinated to specify symbiotic-induced nuclear Ca2+ oscillations remains unknown. Here we discovered an autoactive CNGC15 mutant that generates spontaneous low-frequency Ca2+ oscillations. While CNGC15 produces nuclear Ca2+ oscillations via a gating mechanism involving its helix 1, DMI1 acts as a pacemaker to specify the frequency of the oscillations. We demonstrate that the specificity of symbiotic-induced nuclear Ca2+ oscillations is encoded in its frequency. A high frequency activates endosymbiosis programmes, whereas a low frequency modulates phenylpropanoid pathways. Consequently, the autoactive cngc15 mutant, which is capable of generating both frequencies, has increased flavonoids that enhance AM, root nodule symbiosis and nutrient acquisition. We transferred this trait to wheat, resulting in field-grown wheat with increased AM colonization and nutrient acquisition. Our findings reveal a new strategy to boost endosymbiosis in the field and reduce inorganic fertilizer use while sustaining plant growth.Multicellular organisms control interactions with their environment through the development of specialized barriers in specific cell types. A conserved barrier in plant roots is the endodermal Casparian strip (CS). The CS is made of polymerized lignin and forms a ring-like structure that seals the apoplastic space between the endodermal cells. Most angiosperms also have another root cell type, the exodermis, that is reported to form a barrier. Our understanding of exodermal developmental and molecular regulation, as well as function, is limited as this cell type is absent from the model speciesArabidopsis thaliana. Using tomato (Solanum lycopersicum) as a model system we demonstrate that in this species, the exodermis does not form a CS. Instead, it forms a polar lignin cap with an equivalent barrier function to the endodermal CS. We demonstrate that although endodermal regulators are conserved between Arabidopsis and tomato, exodermal differentiation occurs by a distinct regulatory pathway involving theSlSCZandSlEXO1transcription factors. Although the exodermis and endodermis both produce barriers that restrict mineral ion uptake, they have unique and overlapping roles in their selectivity. Whether conservation and similarities between the endodermis and exodermis exist in other species remains to be determined. Nonetheless, in tomato, these distinct lignin structures have a convergent function with different genetic regulations. Abstract. Iceland is a significant high-latitude dust source area. Airborne Icelandic dust influences the climate system by interacting with radiation, clouds, and biogeochemical cycles; it also affects snow and ice albedo and air quality. These impacts are sensitive to the dust\u2019s mineralogical, chemical, and physical properties. However, comprehensive measurements and analyses of Icelandic dust particles remain limited. This study examines dust samples collected during a field campaign in the Dyngjusandur desert (August\u2013September 2021) using active and passive aerosol sampling. Over 190\u2009000 individual particles, ranging from 0.1 to 120\u2009\u00b5m, were analyzed for their chemical and physical properties using computer-controlled scanning electron microscopy/energy-dispersive X-ray spectroscopy (ccSEM/EDX). Results show heterogeneity in particle size, shape, and composition. The most abundant particle type was medium-Al mixed particles, likely glass-like, comprising 35\u2009%\u201392\u2009% of the aerosol volume. Sulfate particles, suggesting volcanic contributions, were detected in some samples. Iron (Fe)- and titanium (Ti)-rich particles made up 3.3\u2009% and 6\u2009% of the aerosol volume, respectively, mainly in the size fraction <\u20091\u2009\u00b5m. The median aspect ratio ranged from 1.37 to 1.53, increasing with particle size. Our findings highlight key differences in Icelandic dust compared to Saharan dust, including higher iron and titanium content and a lack of potassium in Icelandic dust. Additionally, Icelandic dust shows a size-dependent increase in aspect ratio, unlike Saharan dust, which remains constant. These observations can improve model simulations that account for the effect of high-latitude dust in the Earth system.
In recent decades, there has been increasing recognition of soil as a vital and non\uffe2\uff80\uff90renewable natural resource that provides essential environmental, economic, and social benefits. Agronomic and soil management practices\uffe2\uff80\uff94such as tillage systems, crop rotation, and nutrient applications\uffe2\uff80\uff94significantly influence near\uffe2\uff80\uff90surface soil properties and related ecosystem services. There is growing interest in defining soil quality and establishing specific indicators regarding conservation practices. This systematic review was focused on Long\uffe2\uff80\uff90Term Field Experiments (LTEs) conducted in seven countries: Czech Republic, Italy, Latvia, Lithuania, Poland, Spain, and Turkey. The review examined the most frequently studied soil quality properties related to agroecological practices. Our goal was also to standardize the results based on the advanced works in recent years on soil ecosystem services. The findings underscore the strong interest in sustainable production with a particularly high presence of agroecological soil practices in Long\uffe2\uff80\uff90Term Field Experiments (LTEs), especially in Italy and the Czech Republic. Cereals are among the most extensively studied crops under organic amendments and tillage intensity trials in the reviewed papers. Soil properties related to climate and environmental services (such as organic carbon) are the main indicators studied. Additionally, the review highlights a significant gap in soil biodiversity indicators in the agroecological long\uffe2\uff80\uff90term studies analysed. As a future direction, it is crucial to develop new, holistic soil quality indicators that encompass chemical\uffe2\uff80\uff93physical and biological aspects for soil monitoring and conservation. From its origins in Asia, cultivation of Oryza sativa L. in Portugal has had to adapt to local agroecological conditions. Since the late eighteenth century, there has been significant human intervention in rice production, particularly through public policies aimed at increasing production to achieve national food self-sufficiency. Using national and regional statistics on rice production, this article analyses how public policies on rice cultivation over the last 160 years have impacted and interacted with territorial agroecological conditions and the genetic characteristics of the rice varieties being cultivated. We concluded that public policies led to increased production by favouring the geographical reorganisation of rice production based on the rice varieties used and changing territorial agroecological conditions.
Maize is the world's second most important agricultural crop. The cereal was unknown to Europeans before the end of the 15th century, but since its arrival in Europe, it has changed agriculture, food and landscapes. Terraces where maize was cultivated in the Northwest of the Iberian Peninsula contributed to the formation of local cultures and identities. The history of maize and maize landscape are mementos that help to recover traditional practices, fostering identities, and are crucial for the successful implementation of sustainable policies to provide prosperous futures.
Summary
Maize (Zea mays L.) in the Iberian Peninsula embodies a history of landscape changes where the concepts of \uffe2\uff80\uff98exotic\uffe2\uff80\uff99, \uffe2\uff80\uff98traditional\uffe2\uff80\uff99 and \uffe2\uff80\uff98hybrid\uffe2\uff80\uff99 help to understand the engagements between landscape, farmers, agronomists (since the 19th and 20th centuries) and seeds. Today, landscapes reveal biophysical and ecological changes that reflect a panoply of intentions. A multitude of agents, and their interactions, acted upon those territories over time.
Using historical sources from the leading institutions dedicated to agricultural research in the Iberian Peninsula, this paper aims to (1) contribute to a better understanding of the maize landscape and culture in the Iberian Peninsula and (2) interrogate how landscape changes (and the landscape history of maize) can frame local or regional heritage and identities reflecting customs or ways of life.
The analysis unveils networks of knowledge, agricultural technologies and seed exchange. Politicians, economists, engineers, agronomists, farmers, governmental officials and agricultural industries planned and transformed traditional rural practices into modern and industrialised ones. Experts and politicians, willing to improve agricultural practices and seeds, using hybrid seeds or building new irrigation systems, led to deep social and landscape changes, allowing maize to cover territories far away from its traditional domains. Moreover, despite farmers' resistance, hybrid maize substituted landraces, eroding agrobiodiversity. Nowadays, the south and east regions of the Iberian Peninsula are the main producers of maize (hybrid), whereas in the Northwest maize is an occasional crop, being replaced by vineyards for economic reasons.
The interplay between metal contamination and climate change may exacerbate the negative impact on the soil microbiome and, consequently, on soil health and ecosystem services. We assessed the response of the microbial community of a heavy metal-contaminated soil when exposed to short-term (48 h) variations in air temperature, soil humidity or ultraviolet (UV) radiation in the absence and presence of Enchytraeus crypticus (soil invertebrate). Each of the climate scenarios simulated significantly altered at least one of the microbial parameters measured. Irrespective of the presence or absence of invertebrates, the effects were particularly marked upon exposure to increased air temperature and alterations in soil moisture levels (drought and flood scenarios). The observed effects can be partly explained by significant alterations in soil properties such as pH, dissolved organic carbon, and water-extractable heavy metals, which were observed for all scenarios in comparison to standard conditions. The occurrence of invertebrates mitigated some of the impacts observed on the soil microbial community, particularly in bacterial abundance, richness, diversity, and metabolic activity. Our findings emphasize the importance of considering the interplay between climate change, anthropogenic pressures, and soil biotic components to assess the impact of climate change on terrestrial ecosystems and to develop and implement effective management strategies.
Flavonone 3 hydroxylases (EC 1.14.11.9) are key enzymes in the synthesis of anthocyanins and other flavonoids. Such compounds are involved in seed coat colour and stem pigmentation. Lupinus mutabilis (tarwi) is a legume crop domesticated in the Andean region, valued for the high protein and oil content of its seeds. Tarwi accessions are being selected for cultivation in Europe under defined breeding criteria. Seed coat colour patterns are relevant breeding traits in tarwi, and these are conditioned by anthocyanin content. We identified and isolated part of the tarwi flavonone 3-hydroxylase gene (LmF3h) from two accessions with distinct seed coat colour patterns. Two partial LmF3h paralogues, with predicted 20% amino-acid changes but little predicted tertiary structure alterations, were identified in the coloured seed genotype, while only one was present in the white seed genotype. Upon selection and validation of appropriate reference genes, a RT-qPCR analysis showed that these paralogues have different levels of expression during seed development in both genotypes, although they follow the same expression patterns. DNA and transcription analyses enabled to highlight potential F3H paralogues relatable to seed coat pigmentation in tarwi and, upon biochemical and genetic confirmation, prompt marker-assisted breeding for relevant phenotypic traits associated with flavonoid synthesis.
Lupinus mutabilis (tarwi) is a species of Andean origin with high protein and oil content and regarded as a potential crop in Europe. The success in the introduction of this crop depends in part on in depth knowledge of the intra-specific genetic variability of the collections, enabling the establishment of breeding and conservation programs. In this study, we used morphological traits, Inter-Simple Sequence Repeat markers and genome size to assess genetic and genomic diversity of 23 tarwi accessions under Mediterranean conditions. Phenotypic analyses and yield component studies point out accession LM268 as that achieving the highest seed production, producing large seeds and efficiently using primary branches as an important component of total yield, similar to the L. albus cultivars used as controls. By contrast, accession JKI-L295 presents high yield concentrated on the main stem, suggesting a semi-determinate development pattern. Genetic and genomic analyses revealed important levels of diversity, however not relatable to phenotypic diversity, reflecting the recent domestication of this crop. This is the first study of genome size diversity within L. mutabilis, revealing an average size of 2.05 pg/2C (2001 Mbp) with 9.2% variation (1897\u20132003 Mbp), prompting further studies for the exploitation of this diversity.
Anthracnose, caused by Colletotrichum lupini, is a major limiting factor for lupin production. Tarwi or Andean Lupin (Lupinus mutabilis) is generally regarded as susceptible to anthracnose, but the high protein and oil content of its seeds raise interest in promoting its cultivation in Europe. In this study we evaluated the response to anthracnose of 10 tarwi accessions contrasting in anthocyanin pigmentation, by comparison to white lupin (Lupinus albus), using a contemporary Portuguese fungal isolate. A severity rating scale was optimized, including weighted parameters considering the type of symptoms and organs affected. All tarwi accessions were classified as susceptible, exhibiting sporulating necroses on the main stem from seven days after inoculation. Anthracnose severity was lower on anthocyanin-rich tarwi plants, with accession LM34 standing out as the less susceptible. Accession I82 better combines anthracnose response and yield. In global terms, disease severity was lower on white lupin than on tarwi. Although based on a limited collection, the results of the study show the existence of genetic variability among L. mutabilis towards anthracnose response relatable with anthocyanin pigmentation, providing insights for more detailed and thorough characterization of tarwi resistance to anthracnose.
Food insecurity is a multidimensional and intricate problem, known to have significant implications for individuals, communities, and countries worldwide. Africa has become the continent that is experiencing this uncertainty the most. Food Security (FS) encompasses several aspects such as availability, accessibility, nutrient use, and supply system stability with time and, more recently, other obliges to governance/agency and sustainability. Knowing the interconnection between these aspects and the Ecosystems Services (ES) and understanding the relationship and interactions between FS and ES is important. Moreover, this knowledge may contribute to supporting policies that promote long-term sustainable and secure food systems. Hereby, a conceptual framework is presented, that examines interactions between food insecurity drivers and ecosystem change drivers and the combined influence on ES. Our review further introduces existing trade-offs between ES on account of agricultural intensification vs. key existing strategies to promote sustainable agricultural production. These strategies include climate-smart agriculture, sustainably managed land, and effective handling of water resources. In the end, the potential of Payment for Ecosystem Services (PES), as a suitable approach to ensuring these strategies are adopted, especially in African countries where sustainable financial incentives are currently under-explored is discussed. In resume, this review aims to make a conceptual contribution to understanding how drivers of food insecurity influence drivers of ecosystem changes, the impact of these influences on the services of ecosystems, and how sustainable agro approaches and PES introduction can help to reduce such negative impacts.
Lupinus mutabilis is an important source of protein in different Andean countries, and its use in diets, particularly those of less wealthy individuals, has been observed for thousands of years. There is an increasing demand for protein crops suitable for Europe and this species is a potential candidate. Assessment of Lupinus mutabilis genetic material in European conditions started more than 40 years ago, with the characterization of a vast number of accessions from the Andean region. In this review, abiotic and biotic constraints to L. mutabilis cultivation in European soil and climatic conditions are discussed, and cultivation management practices are suggested. The beneficial interaction of L. mutabilis with Bradyrhizobium strains in the soil and various pollinator species is also discussed, and the effect of abiotic stresses on these interactions is highlighted. Prospects of alternative uses of L. mutabilis biomass in Northern Europe and opportunities for breeding strategies are discussed. In conclusion, the different approach to crop modeling for Southern and Northern European climatic conditions is highlighted.
The introduction of Lupinus mutabilis (Andean lupin) in Europe will provide a new source of protein and oil for plant-based diets and biomass for bio-based products, while contributing to the improvement of marginal soils. This study evaluates for the first time the phenotypic variability of a large panel of L. mutabilis accessions both in their native environment and over two cropping conditions in Europe (winter crop in the Mediterranean region and summer crop in North-Central Europe), paving the way for the selection of accessions adapted to specific environments. The panel of 225 accessions included both germplasm pools from the Andean region and breeding lines from Europe. Notably, we reported higher grain yield in Mediterranean winter-cropping conditions (18 g/plant) than in the native region (9 g/plant). Instead, North European summer-cropping conditions appear more suitable for biomass production (up to 2 kg/plant). The phenotypic evaluation of 16 agronomical traits revealed significant variation in the panel. Principal component analyses pointed out flowering time, yield, and architecture-related traits as the main factors explaining variation between accessions. The Peruvian material stands out among the top-yielding accessions in Europe, characterized by early lines with high grain yield (e.g., LIB065, LIB072, and LIB155). Bolivian and Ecuadorian materials appear more valuable for the selection of genotypes for Andean conditions and for biomass production in Europe. We also observed that flowering time in the different environments is influenced by temperature accumulation. Within the panel, it is possible to identify both early and late genotypes, characterized by different thermal thresholds (600\uffc2\uffb0C\uffe2\uff80\uff93700\uffc2\uffb0C and 1,000\uffe2\uff80\uff931,200\uffc2\uffb0C GDD, respectively). Indications on top-yielding and early/late accessions, heritability of morpho-physiological traits, and their associations with grain yield are reported and remain largely environmental specific, underlining the importance of selecting useful genetic resources for specific environments. Altogether, these results suggest that the studied panel holds the genetic potential for the adaptation of L. mutabilis to Europe and provide the basis for initiating a breeding program based on exploiting the variation described herein.Abstract
We analyse the dynamic evolution of disease outbreak risk after the main waves of the 1918-19 \u201cSpanish flu\u201d pandemic in the US and in major cities in the UK, and after the 1890-91 \u201cRussian flu\u201d pandemic in England and Wales. We compile municipal public health records and use national data to model the stochastic process of mortality rates after the main pandemic waves as a sequence of bounded Pareto distributions with an exponentially decaying tail parameter. In all cases, we find elevated mortality risk lasting nearly two decades. An application to COVID-19 under model uncertainty shows that in 80% of model-predicted time series, the annual probability of outbreaks exceeding 500 deaths per million is above 20% for a decade, remaining above 10% for two decades.
", "keywords": ["0301 basic medicine", "03 medical and health sciences", "archive data", "0302 clinical medicine", "ddc:330", "pandemics", "influenza", "Covid-19", "outbreak risk", "3. Good health"]}, "links": [{"href": "https://doi.org/10419/249020"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/SSRN%20Electronic%20Journal", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10419/249020", "name": "item", "description": "10419/249020", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10419/249020"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2021-01-01T00:00:00Z"}}, {"id": "10451/45438", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-03T16:26:58Z", "type": "Journal Article", "created": "2020-07-09", "title": "The distribution of herbivores between leaves matches their performance only in the absence of competitors", "description": "AbstractFew studies have tested how plant quality and the presence of competitors interact in determining how herbivores choose between different leaves within a plant. We investigated this in two herbivorous spider mites sharing tomato plants: Tetranychus urticae, which generally induces plant defenses, and Tetranychus evansi, which suppresses them, creating asymmetrical effects on coinfesting competitors. On uninfested plants, both herbivore species preferred young leaves, coinciding with increased mite performance. On plants with heterospecifics, the mites did not prefer leaves on which they had a better performance. In particular, T.\uffc2\uffa0urticae avoided leaves infested with T.\uffc2\uffa0evansi, which is in agreement with T.\uffc2\uffa0urticae being outcompeted by T.\uffc2\uffa0evansi. In contrast, T.\uffc2\uffa0evansi did not avoid leaves with the other species, but distributed itself evenly over plants infested with heterospecifics. We hypothesize that this behavior of T.\uffc2\uffa0evansi may prevent further spread of T.\uffc2\uffa0urticae over the shared plant. Our results indicate that leaf age determines within\uffe2\uff80\uff90plant distribution of herbivores only in absence of competitors. Moreover, they show that this distribution depends on the order of arrival of competitors and on their effects on each other, with herbivores showing differences in behavior within the plant as a possible response to the outcome of those interactions.