Root architectural phenotypes are promising targets for crop breeding, but root architectural effects on microbial associations in agricultural fields are not well understood. Architecture determines the location of microbial associations within root systems, which, when integrated with soil vertical gradients, determines the functions and the metabolic capability of rhizosphere microbial communities. We argue that variation in root architecture in crops has important implications for root exudation, microbial recruitment and function, and the decomposition and fate of root tissues and exudates. Recent research has shown that the root microbiome changes along root axes and among root classes, that root tips have a unique microbiome, and that root exudates change within the root system depending on soil physicochemical conditions. Although fresh exudates are produced in larger amounts in root tips, the rhizosphere of mature root segments also plays a role in influencing soil vertical gradients. We argue that more research is needed to understand specific root phenotypes that structure microbial associations and discuss candidate root phenotypes that may determine the location of microbial hotspots within root systems with relevance to agricultural systems.Grazers can have a large impact on ecosystem processes and are known to change vegetation composition. However, knowledge of how the long-term presence of grazers affects soil carbon sequestration is limited. In this study, we estimated total accumulated organic carbon in soils of a back-barrier salt marsh and determined how this is affected by long-term grazing by both small and large grazers in relation to age of the ecosystem. In young marshes, where small grazers predominate, hare and geese have a limited effect on total accumulated organic carbon. In older, mature marshes, where large grazers predominate, cattle substantially enhanced carbon content in the marsh soil. We ascribe this to a shift in biomass distribution in the local vegetation towards the roots in combination with trampling effects on the soil chemistry. These large grazers thus act as ecosystem engineers: their known effect on soil compaction (based on a previous study) enhances anoxic conditions in the marsh soil, thereby reducing the oxygen available for organic carbon decomposition by the local microbial community. This study showed that the indirect effects of grazing can significantly enhance soil carbon storage through changing soil abiotic conditions. This process should be taken into account when estimating the role of ecosystems in reducing carbon dioxide concentration in the atmosphere. Ultimately, we propose a testable conceptual framework that includes 3 pathways by which grazers can alter carbon storage: (1) through above-ground biomass removal, (2) through alteration of biomass distribution towards the roots and/or (3) by changing soil abiotic conditions that affect decomposition.
", "keywords": ["Carbon sequestration", "0106 biological sciences", "IMPACT", "SEA-LEVEL RISE", "01 natural sciences", "Coastal wetland", "Climate change", "Biology", "Soil compaction", "Succession", "VEGETATION SUCCESSION", "0105 earth and related environmental sciences", "2. Zero hunger", "CLIMATE-CHANGE", "WETLAND SOILS", "WADDEN SEA", "15. Life on land", "PRODUCTIVITY GRADIENT", "6. Clean water", "Chemistry", "Grazing", "ORGANIC-MATTER", "NORTH-SEA", "REDOX OSCILLATION", "13. Climate action", "Redox potential"]}, "links": [{"href": "https://doi.org/10.3354/meps11447"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Marine%20Ecology%20Progress%20Series", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.3354/meps11447", "name": "item", "description": "10.3354/meps11447", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.3354/meps11447"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2015-10-14T00:00:00Z"}}, {"id": "10.5061/dryad.50g8322", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-25T16:21:24Z", "type": "Dataset", "title": "Data from: Alteration of nitrous oxide emissions from floodplain soils by aggregate size, litter accumulation and plant\u2013soil interactions", "description": "unspecifiedSemi-terrestrial soils such as floodplain soils are considered potential hot spots of nitrous oxide (N2O) emissions. Microhabitats in the soil \u2013 such as within and outside of aggregates, in the detritusphere, and/or in the rhizosphere \u2013 are considered to promote and preserve specific redox conditions. Yet our understanding of the relative effects of such microhabitats and their interactions on N2O production and consumption in soils is still incomplete. Therefore, we assessed the effect of aggregate size, buried leaf litter, and plant\u2013soil interactions on the occurrence of enhanced N2O emissions under simulated flooding/drying conditions in a mesocosm experiment. We used two model soils with equivalent structure and texture, comprising macroaggregates (4000\u2013250\u2009\u00b5m) or microaggregates (<250\u2009\u00b5m) from a N-rich floodplain soil. These model soils were planted with basket willow (Salix viminalis L.), mixed with leaf litter or left unamended. After 48\u2009h of flooding, a period of enhanced N2O emissions occurred in all treatments. The unamended model soils with macroaggregates emitted significantly more N2O during this period than those with microaggregates. Litter addition modulated the temporal pattern of the N2O emission, leading to short-term peaks of high N2O fluxes at the beginning of the period of enhanced N2O emission. The presence of S. viminalis strongly suppressed the N2O emission from the macroaggregate model soil, masking any aggregate-size effect. Integration of the flux data with data on soil bulk density, moisture, redox potential and soil solution composition suggest that macroaggregates provided more favourable conditions for spatially coupled nitrification\u2013denitrification, which are particularly conducive to net N2O production. The local increase in organic carbon in the detritusphere appears to first stimulate N2O emissions; but ultimately, respiration of the surplus organic matter shifts the system towards redox conditions where N2O reduction to N2 dominates. Similarly, the low emission rates in the planted soils can be best explained by root exudation of low-molecular-weight organic substances supporting complete denitrification in the anoxic zones, but also by the inhibition of denitrification in the zone, where rhizosphere aeration takes place. Together, our experiments highlight the importance of microhabitat formation in regulating oxygen (O2) content and the completeness of denitrification in soils during drying after saturation. Moreover, they will help to better predict the conditions under which hot spots, and \u201chot moments\u201d, of enhanced N2O emissions are most likely to occur in hydrologically dynamic soil systems like floodplain soils.", "keywords": ["floodplain soils", "Salix viminalis", "emission patterns", "litter", "nitrous oxide", "13. Climate action", "aggregate size", "redox potentials", "15. Life on land", "6. Clean water"], "contacts": [{"organization": "Ley, Martin, Lehmann, Moritz F., Niklaus, Pascal A., Luster, J\u00f6rg,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.5061/dryad.50g8322"}, {"rel": "self", "type": "application/geo+json", "title": "10.5061/dryad.50g8322", "name": "item", "description": "10.5061/dryad.50g8322", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5061/dryad.50g8322"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-11-28T00:00:00Z"}}, {"id": "10.5281/zenodo.8383036", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-25T16:23:40Z", "type": "Dataset", "title": "Soil redox potential vs. soil microbial activity and structure", "description": "Open Access{'references': ['https://doi.org/10.1007/s11104-023-06305-y']}", "keywords": ["2. Zero hunger", "soil health", "on farm research", "soil redox potential"], "contacts": [{"organization": "Mattila, Tuomas Johannes", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.5281/zenodo.8383036"}, {"rel": "self", "type": "application/geo+json", "title": "10.5281/zenodo.8383036", "name": "item", "description": "10.5281/zenodo.8383036", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5281/zenodo.8383036"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2023-09-27T00:00:00Z"}}, {"id": "20.500.11850/645010", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-25T16:25:15Z", "type": "Journal Article", "created": "2023-10-26", "title": "Location: root architecture structures rhizosphere microbial associations", "description": "AbstractRoot architectural phenotypes are promising targets for crop breeding, but root architectural effects on microbial associations in agricultural fields are not well understood. Architecture determines the location of microbial associations within root systems, which, when integrated with soil vertical gradients, determines the functions and the metabolic capability of rhizosphere microbial communities. We argue that variation in root architecture in crops has important implications for root exudation, microbial recruitment and function, and the decomposition and fate of root tissues and exudates. Recent research has shown that the root microbiome changes along root axes and among root classes, that root tips have a unique microbiome, and that root exudates change within the root system depending on soil physicochemical conditions. Although fresh exudates are produced in larger amounts in root tips, the rhizosphere of mature root segments also plays a role in influencing soil vertical gradients. We argue that more research is needed to understand specific root phenotypes that structure microbial associations and discuss candidate root phenotypes that may determine the location of microbial hotspots within root systems with relevance to agricultural systems.