Résumé
Lakes are essential ecosystems that provide a large number of ecosystem services whose quality is strongly impacted by human pressures. Optimal uses of lakes require adapted management practices which in turn rely on physico-chemical and biological monitoring. Long-term ecological monitoring provides large sets of environmental data. When such data are available, they have to be associated to metadata and to be stored properly to be accessible and useable by the scientific community. We present a data informatics system accessible to anyone who requests it. Maintained online since 2014 (https://si-ola.inrae.fr), it is originated from the Observatory on LAkes (OLA). It contains long-term data from 4 peri-alpine lakes (Lakes Aiguebelette, Annecy, Bourget, Geneva/Léman) and 24 high-altitude lakes of the northern French Alps. We describe the generated long-term data series, the data type, the methodologies and quality control procedures, and the information system where data are made accessible. Data use is allowed under the condition of providing reference to the original source. We show here how such a platform clearly enhances data sharing and scientific collaboration. Various studies referring to these data are regularly published in peer-reviewed journals; providing in fine a better understanding of lakes’ ecosystems functioning under local and global pressures.
Auteurs, date et publication :
Auteurs Frédéric Rimet , Orlane Anneville , Denis Barbet , Cécile Chardon , Laura Crépin , Isabelle Domaizon , Jean-Marcel Dorioz , Laurent Espinat , Victor Frossard , Jean Guillard , Chloé Goulon , Valérie Hamelet , Jean-Christophe Hustache , Stéphan Jacquet , Leslie Lainé , Bernard Montuelle , Pascal Perney , Philippe Quetin , Serena Rasconi , Antoine Schellenberger
Publication : Journal of Limnology
Date : 2020
Catégorie(s)
#INRAE #OLAAuteurs, date et publication :
Auteurs Jade A. Ezzedine , Louis Jacas , Yves Desdevises , Stéphan Jacquet
Publication : Frontiers in Microbiology
Date : 2020
Volume : 11
Pages : 98
Catégorie(s)
#INRAE #OLARésumé
Forest soil fertility can be defined as a combination of physical, chemical and biological factors characterising the biomass production capacity of the soil. However, numerous ecological variables affect tree growth and the aim of the present study was to investigate the specific influence of soil chemical properties on tree productivity at 49 acidic forest sites. A standardized tree productivity index based on tree height expressed as dominant height of the studied stand divided by maximum tree height observed at the same age for the same species in the same climatic region was firstly computed at each site. This index is assumed to limit the influence of species, ages and climate. A soil database was also compiled with data on soil properties from 47 temperate (France) and two tropical (Congo, Brazil) sites. Data included seven tree species, varying in age from 1 to 175 years. Commonly used indicators such as C:N ratio, soil pH, as well as available and total pools of soil nutrients were compared to the standardized tree productivity index, to find the most reliable indicator(s). Nutrient pools at fixed mineral soil depths (down to 100 cm) were used, as well as (for 11 stands) the depth comprising 95% of fine roots. Our results show that none of the common soil chemical parameters tested in this paper could individually explain stand productivity. Combinations of different parameters were also tested using PCA and they could better explain the variability of the data set but without being able to separate the sites according to their standardized tree productivity index. Moreover, random Forests performed on our dataset were unable to properly predict the standardized tree productivity index. Our results reinforce the idea that the influence of the soil chemical fertility on stand productivity is complex and the soil chemical parameters alone (individually or combined) are poor predictors of tree productivity as assessed by the H0:Hmax index. In this paper we focused on static soil chemical indicator and more dynamic indictors, such as nutrient fluxes involved in the biogeochemical cycles, could better explain stand productivity. A companion paper (Legout et al., 2020) focuses on the connection between productivity and different components of the biogeochemical cycle, using data from 11 of the stands presented in this paper.
Auteurs, date et publication :
Auteurs Karna Hansson , Jean-Paul Laclau , Laurent Saint-André , Louis Mareschal , Gregory van der Heijden , Claude Nys , Manuel Nicolas , Jacques Ranger , Arnaud Legout
Publication : Forest Ecology and Management
Date : 2020
Volume : 461
Pages : 117843
Catégorie(s)
#ANR-Citation #FORET Breuil #INRAERésumé
Many forest ecosystems are developed on acidic and nutrient-poor soils and it is not yet clearly understood how forests sustain their growth with low nutrient resources. In forestry, the soil chemical fertility is commonly defined, following concepts inherited from agronomy, as the pool of plant-available nutrients in the soil at a given time compared to the nutritional requirement of the tree species. In this two-part study, Part 1 (Hansson et al., 2020) showed, through the compiled dataset of 49 forest ecosystems in France, Brazil and Republic of Congo, the limits of this definition of soil chemical fertility in forest ecosystem contexts. In this study (Part 2), we investigated the nutrient pools and fluxes between the different ecosystem compartments at 11 of the 49 sites in order to better characterize the role of the biogeochemical cycling of nutrients in the chemical fertility of forest ecosystems, and in particular the roles of the biological and geochemical components of biogeochemical cycling. The analysis of our dataset shows different types of biogeochemical functioning. When the geochemical component (inputs through mineral weathering and/or atmospheric inputs, capillary rise) is predominant, sufficient nutrients are provided to the plant-soil system to ensure tree nutrition and growth. Conversely, when the geochemical component of the cycle brings too few nutrients to the plant-soil system, the biological component (litterfall, plant internal cycling) becomes predominant in tree nutrition and growth. In the latter case, forest production may be high even when pools of nutrients in the soil reservoir are low because small but active nutrient fluxes may continuously replenish the soil reservoir or may directly ensure tree nutrition by bypassing the soil reservoir. This study highlights the necessity to include biogeochemical cycling and recycling fluxes in the definition and diagnosis methods of soil chemical fertility in forest ecosystems. We show that the chemical fertility is not only supported by the soil in forest ecosystem but by the sum of all the ecosystem’s compartments and fluxes between these pools.
Auteurs, date et publication :
Auteurs Arnaud Legout , Karna Hansson , Gregory van der Heijden , Jean-Paul Laclau , Louis Mareschal , Claude Nys , Manuel Nicolas , Laurent Saint-André , Jacques Ranger
Publication : Forest Ecology and Management
Date : 2020
Volume : 461
Pages : 117844
Catégorie(s)
#ANR-Citation #FORET Breuil #INRAERésumé
Theory surrounding landscape ecology has been built on the species distribution of birds and plants, but increasing evidence now exists for below-ground organisms, whose dispersal may also be affected by above-ground landscape structures. Uncertainties remain for how communities of microorganisms respond to landscape structure over time, and whether some groups of microorganisms react more than others. Here, we investigated if fungal or bacterial diversity is driven by the amount of forest cover in the current or the past landscape. We tested the habitat amount hypothesis (HAH) on ancient forests of the Cevennes national park, that experienced increased fragmentation 150 years ago, and are today surrounded by recent forests. As ancient forests are often more diverse in plant species, we hypothesized that the higher quantity of ancient forests in the landscape, the richer local fungal and bacterial communities would be. More precisely, we expected that ectomycorrhizal fungi, and pathotrophic fungi, often indicators of mature forests, would be also more sensitive to forest history and therefore to the quantity of ancient forests than bacteria and saprotrophic fungi. We sampled 40 soil cores per 0.5 ha, pooled in 8 composite samples per plot in 27 landscapes and sequenced ITS1 and 16S markers by Illumina-Mi seq. To identify functional groups of fungi, we relied on their taxonomy and the use of public databases. Our results partly follow the HAH, as fungal richness was positively related with the quantity of ancient forests in the landscape and not by the focal patch size. Ectomycorrhizal and pathotrophic fungi were positively affected by the ancient forest cover, and so were saprotrophic ones, but not bacteria. Local factors also shaped the communities such as soil composition and elevation, confirming classical patterns in soil microbial ecology. Interestingly, past landscape structure was better at explaining fungal community richness than contemporary landscape, suggesting a time lag in the response of communities to landscape modification and a potential extinction debt. Our results reveal the importance of below-ground communities in studies of landscape and historical ecology, with their structure and functions likely to be intimately linked with soil and landscape history.
Auteurs, date et publication :
Auteurs Sophie Mennicken , Floriane Kondratow , Florian Buralli , Sophie Manzi , Emilie Andrieu , Melanie Roy , Antoine Brin
Publication : FRONTIERS IN ECOLOGY AND EVOLUTION
Date : 2020
Volume : 8
Catégorie(s)
#ANR-Citation #Genosol #INRAERésumé
Spatial heterogeneity in plant and soil properties plays a key role for biogeochemical cycling, nutrient losses and ecosystem function. Different management practices are expected to induce varying levels of spatial heterogeneity in agroecosystems, but the effects of contrasting biomass removal regimes and herbivore species on grassland variability and spatial pattern have faced little attention. We carried out a spatially-explicit sampling campaign and geostatistical analyses to quantify the spatial heterogeneity of the biomass and N in plants and soil for three management treatments (mowing, cattle grazing and sheep grazing) within a long-term grassland experiment. All plant and soil properties showed within-site variation, irrespective of management treatment. Within-site variation in plant variables could be ranked as grazing > mowing. Cattle grazing increased variability in vegetation structure, soil mineral N and soil C:N compared with sheep grazing. In addition, the cattle-grazed field had a higher degree of spatial structure and a more coarse-grained pattern of spatial heterogeneity in plant properties than the sheep-grazed field. However, both grazing treatments showed spatial asynchrony in above- and below-ground responses to grazing. These results demonstrate the importance of herbivore species identity as a driver of grassland spatial heterogeneity, with implications for spatial uncoupling of nutrient cycles at the field scale.
Auteurs, date et publication :
Auteurs Juliette M. G. Bloor , Antoine Tardif , Julien Pottier
Publication : Agronomy
Date : 2020
Volume : 10
Issue : 5
Pages : 716
Catégorie(s)
#ACBB #ACBB Theix #INRAERésumé
The 10Be, 137Cs and 210Pbxs radionuclide fallout has been used for the last several decades to quantify various soil and geomorphological processes on different time scales. However, a basic assumption of the studies relying on these radionuclides is that they have a strong affinity for soil particles and that their mobility in soil solution and losses through leaching can be neglected. Another area of the scientific literature deals with the radionuclide mobility in soils as solute. In that context, the objective of this work is to determine the pedological conditions under which this hypothesis of poor solute mobility of radionuclides is valid. To this end, meteoric 10Be, 137Cs and 210Pbxs concentrations were measured in six soil profiles representative of 5 soil types contrasted in terms of physico-chemical properties: an Andosol and a Luvisol under pasture, a Ferralsol and a Leptosol under forest and a Podzol both under forest and cultivation. The main soil properties (soil pH, organic carbon (OC) content, particle size distribution and specific extractions) were measured. The <2 µm fraction was extracted to measure radionuclide activities and undertake mineralogical analysis. Results show that meteoric 10Be is significantly leached from soils whose pHw is lower than 5, regardless of the <2 µm particle proportion and Fe oxides content. Significant 137Cs losses through leaching can generally be neglected except in sandy soils whose pHw is lower than 4.5 (Podzol). No significant 210Pbxs losses were evidenced. For the three radionuclides considered, the major part of their budget is associated with the <2 µm fraction. However, concerning the Andosol, the proportion of radionuclide budget associated with the <2 µm fraction represents <40%. With regards to the forested Podzol, two thirds of the 210Pbxs budget is associated with the litter. Well-crystallized Fe oxides, illite and interlayered clay minerals as well as allophane, imogolite and other Al-phases in the Andosol and kaolinite in highly weathered acidic soils (Ferralsol) were found to efficiently retain 10Be. Finally, litter degradation and the content of large particulate organic matter were shown to control 210Pbxs concentrations. As expected, our results highlight strong contrasts in the retention of the considered isotopes according to soil physico-chemical properties. Accordingly, their mobility and losses through solute transport should be considered when using them for quantifying solid transport and future mass transport models must be improved, in particular through the addition of a solute transfer term. Otherwise, soil redistribution might be strongly overestimated for Podzols, Ferralsols and also most probably for other acidic tropical soil types (Nitisols, Acrisols, Plinthisols).
Auteurs, date et publication :
Auteurs Felix de Tombeur , Sophie Cornu , Didier Bourlès , Adrien Duvivier , Julie Pupier , Team Aster , Michel Brossard , Olivier Evrard
Publication : Geoderma
Date : 2020
Volume : 367
Pages : 114242
Catégorie(s)
#ACBB #ACBB Mons #INRAERésumé
Animal grazing in integrated crop-livestock systems (ICLS) results in continuous nutrient release to forage plants and crops in succession. This study aimed to assess sheep dung composition and decomposition rates under distinct grazing intensities and at different development stages of Italian ryegrass pasture (Lolium multiflorum Lam.), and to evaluate dung phosphorus (P) and potassium (K) release dynamics during two annual ICLS cycles (2015 and 2016) in southern Brazil. Treatments consisted of two grazing intensities (moderate and light) and two pasture development stages (vegetative and post-flowering), arranged in a randomized complete block design with split-split-plots and four replicates. Dry matter (DM) decomposition and P and K release rates were determined using litter bags with sheep dung. Grazing intensity did not affect sheep dung composition. Forage consumed at different development stages altered sheep dung composition, decomposition, and P and K release rates. Dung sampled at pasture vegetative stage showed P and K contents 16% and 7% higher, respectively, than dung from the post-flowering stage. Dung collected at pasture post-flowering stage had 26% more cellulose and 34% more hemicellulose compared to dung from the vegetative stage in 2016. P and K release was greater for dung from pasture vegetative stage, reaching 3.7 and 12.9 kg ha−1 of P and K, respectively. Further evaluations are still needed considering the quantification and release of nutrients in each of the different compartments (pasture, urine, and dung residues) that compose the system.
Auteurs, date et publication :
Auteurs Fernando Arnuti , Luiz Gustavo de O. Denardin , Pedro Arthur de A. Nunes , Lucas A. Alves , Diego Cecagno , Júlia de Assis , Walker da S. Schaidhauer , Ibanor Anghinoni , Abad Chabbi , Paulo César de F. Carvalho
Publication : Agronomy
Date : 2020
Volume : 10
Issue : 8
Pages : 1162
Catégorie(s)
#ACBB #ACBB Lusignan #INRAERésumé
In subtropical lowlands, the introduction of soybean and livestock in rotation are an alternative to rice monoculture. Due to the nutrient cycling process improved by animal grazing in winter fertilized pastures, soybean may not respond to mineral fertilization under a no-till integrated crop–livestock system (ICLS). Thus, the objectives of this study were to evaluate (i) the soybean yield response to different fertilization levels of phosphorus (P) and potassium (K) and (ii) the relationship between soybean yield and soil chemical properties sampled in different soil layers, in a no-till ICLS in subtropical lowlands. Two field studies were conducted in a system that included a soybean-flooded rice rotation integrated with cattle grazing during the winter season. During the 2015/2016 cropping season, five levels of P and K fertilization were applied to the soil. During the 2017/2018 cropping season, the relationships between soybean yield and soil chemical properties were evaluated under no fertilization treatment. Soybean yield under an ICLS did not respond to P and K fertilization, even when the soil P level was below the critical threshold. The associations between soybean yield and soil chemical properties were greatest in the 10–20 cm soil layer as compared with the 0–10 cm soil layer, especially for available P, followed by pH and soil organic matter (SOM). The crop rotation and ICLS adoption under no-till reduced the soybean reliance for mineral fertilization prior to cropping. Results of this study inform producers of possible fertilization adjustments, in which supplementing mineral fertilizer for soybean may not be necessary.
Auteurs, date et publication :
Auteurs Luiz Gustavo de O. Denardin , Amanda P. Martins , Leonardo M. Bastos , Ignacio A. Ciampitti , Ibanor Anghinoni , Fernanda G. Moojen , Paulo César de F. Carvalho , Min Huang , Abad Chabbi
Publication : Agronomy
Date : 2020
Volume : 10
Issue : 9
Pages : 1371
Catégorie(s)
#ACBB #ACBB Lusignan #INRAERésumé
Background: Goldfish is an important model for various areas of research, including neural development and behavior and a species of significant importance in aquaculture, especially as an ornamental species. It has a male heterogametic (XX/XY) sex determination system that relies on both genetic and environmental factors, with high temperatures being able to produce female-to-male sex reversal. Little, however, is currently known on the molecular basis of genetic sex determination in this important cyprinid model. Here we used sequencing approaches to better characterize sex determination and sex-chromosomes in an experimental strain of goldfish. Results: Our results confirmed that sex determination in goldfish is a mix of environmental and genetic factors and that its sex determination system is male heterogametic (XX/XY). Using reduced representation (RAD-seq) and whole genome (pool-seq) approaches, we characterized sex-linked polymorphisms and developed male specific genetic markers. These male specific markers were used to distinguish sex-reversed XX neomales from XY males and to demonstrate that XX female-to-male sex reversal could even occur at a relatively low rearing temperature (18 degrees C), for which sex reversal has been previously shown to be close to zero. We also characterized a relatively large non-recombining region (similar to 11.7 Mb) on goldfish linkage group 22 (LG22) that contained a high-density of male-biased genetic polymorphisms. This large LG22 region harbors 373 genes, including a single candidate as a potential master sex gene, i.e., the anti-Mullerian hormone gene (amh). However, no sex-linked polymorphisms were detected in the coding DNA sequence of the goldfishamhgene. Conclusions: These results show that our goldfish strain has a relatively large sex locus on LG22, which is likely the Y chromosome of this experimental population. The presence of a few XX males even at low temperature also suggests that other environmental factors in addition to temperature could trigger female-to-male sex reversal. Finally, we also developed sex-linked genetic markers, which will be important tools for future research on sex determination in our experimental goldfish population. However, additional work would be needed to explore whether this sex locus is conserved in other populations of goldfish.
Auteurs, date et publication :
Auteurs Ming Wen , Romain Feron , Qiaowei Pan , Justine Guguin , Elodie Jouanno , Amaury Herpin , Christophe Klopp , Cedric Cabau , Margot Zahm , Hugues Parrinello , Laurent Journot , Shawn M. Burgess , Yoshihiro Omori , John H. Postlethwait , Manfred Schartl , Yann Guiguen
Publication : BMC GENOMICS
Date : 2020
Volume : 21
Issue : 1