Cover crop (CC) mixtures offer a unique set of advantages that can enhance soil health and agricultural productivity when compared to pure stand CC. However, a quantitative understanding of the varying contributions of different carbon (C) input pathways in CC mixtures is lacking. To address these gaps, a field experiment with multiple-pulse labelling with 13CO2 was used to quantify C-derived from CC mixtures via plant biomass, as well as via phyllo- and rhizodeposition. We assessed the impact of preceding main crops (barley, barley-pea, pea, and faba bean) on soil C input to 75 cm depth by two CC treatments (pure stand ryegrass versus a mixture of chicory, plantain, and ryegrass) and their effect on spontaneous flora (SF) biomass and diversity. In topsoil layers (0\u201325 cm), net C lost to soil via phyllo- and rhizodeposition was higher with mixed CC (30 g C m\u22122) than pure stand ryegrass (25 g C m\u22122). Between 25 and 75 cm, mixed CC and pure stand CC had similar C inputs via rhizodeposition despite larger root biomass in mixed CC. Cover crops reduced SF biomass and diversity, with mixed CC exerting the strongest suppressive effect, reducing biomass (individuals counted) by 57 % compared to the control. The improved efficiency of mixed CC was attributed to species complementarity in leaf and root patterns, resource utilization, and nutrient uptake. In conclusion, well-designed mixed CC had a greater positive impact on soil C inputs and suppression of SF compared to CC pure stand with ryegrass, resulting from complementary above and belowground traits.
", "keywords": ["0106 biological sciences", "Soil organic carbon", "Phyllodeposition", "CO labeling", "0401 agriculture", " forestry", " and fisheries", "Biodiversity", "04 agricultural and veterinary sciences", "Species mixtures", "Rhizodeposition", "01 natural sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.geodrs.2024.e00879"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Geoderma%20Regional", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.geodrs.2024.e00879", "name": "item", "description": "10.1016/j.geodrs.2024.e00879", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.geodrs.2024.e00879"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2024-12-01T00:00:00Z"}}, {"id": "10.1016/j.soilbio.2005.10.002", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:16:04Z", "type": "Journal Article", "created": "2005-11-09", "title": "Short And Long-Term Effects Of Elevated Co2 On Lolium Perenne Rhizodeposition And Its Consequences On Soil Organic Matter Turnover And Plant N Yield", "description": "It is still unclear whether elevated CO 2 increases plant root exudation and consequently affects the soil microbial biomass. The effects of elevated CO 2 on the fate of the C and nitrogen (N) contained in old soil organic matter pools is also unclear. In this study the short and long-term effects of elevated CO 2 on C and N pools and fluxes were assessed by growing isolated plants of ryegrass (Lolium perenne) in glasshouses at elevated and ambient atmospheric CO 2 and using soil from the New Zealand FACE site that had >4 years exposure to CO 2 enrichment. Using 14 CO 2 pulse labelling, the effects of elevated CO 2 on C allocation within the plant-soil system were studied. Under elevated CO 2 more root derived C was found in the soil and in the microbial biomass 48 h after labelling. The increased availability of substrate significantly stimulated soil microbial growth and acted as priming effect, enhancing native soil organic matter decomposition regardless of the mineral N supply. Despite indications of faster N cycling in soil under elevated CO 2 , N availability to plants stayed unchanged. Soil previously exposed to elevated CO 2 exhibited a higher N cycling rate but again there was no effect on plant N uptake. With respect to the difficulties of extrapolating glasshouse experiment results to the field, we concluded that the accumulation of coarse organic matter observed in the field under elevated CO 2 was probably not created by an imbalance between C and N but was likely to be due to more complex phenomena involving soil mesofauna and/or other nutrients limitations.", "keywords": ["580", "RHIZODEPOSITION", "2. Zero hunger", "RAY GRASS ANGLAIS", "PRIMING EFFECT", "15N", "RYEGRASS", "0401 agriculture", " forestry", " and fisheries", "04 agricultural and veterinary sciences", "[SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study", "15. Life on land", "ELEVATED CO2", "[SDV.SA.SDS] Life Sciences [q-bio]/Agricultural sciences/Soil study"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2005.10.002"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2005.10.002", "name": "item", "description": "10.1016/j.soilbio.2005.10.002", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2005.10.002"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2006-06-01T00:00:00Z"}}, {"id": "10.1016/j.soilbio.2005.06.023", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:16:04Z", "type": "Journal Article", "created": "2005-07-28", "title": "Effects Of Elevated Co2 Concentration On Rhizodeposition From Lolium Perenne Grown On Soil Exposed To 9 Years Of Co2 Enrichment", "description": "Abstract The effects of enriched CO 2 atmosphere on partitioning of recently assimilated carbon were investigated in a plant-soil-microorganism system in which Lolium perenne seedlings were planted into cores inserted into the resident soil within a sward that had been treated with elevated CO 2 for 9 consecutive years, under two N fertilisation levels (Swiss FACE experiment). The planted cores were excavated from the ambient (35\u00a0Pa pCO 2 ) and enriched (60\u00a0Pa pCO 2 ) rings at two dates, in spring and autumn, during the growing season. The cores were brought back to the laboratory for 14 C labelling of shoots in order to trace the transfer of recently assimilated C both within the plant and to the soil and microbial biomass. At the spring sampling, high N supply stimulated shoot and total dry matter production. Consistently, high N enhanced the allocation of recently fixed C to shoots, and reduced it to belowground compartments. Elevated CO 2 had no consequences for DM or the pattern of C allocation. At the autumn sampling, at high N plot, yield of L. perenne was stimulated by elevated CO 2 . Consistently, 14 C was preferentially allocated aboveground and, consequently belowground recent C allocation was depressed and rhizodeposition reduced. At both experimental periods, total soil C content was similar in all treatments, providing no evidence for soil carbon sequestration in the Swiss Free Air CO 2 Enrichment experiment (FACE) after 9 years of enrichment. Recently assimilated C and soil C were mineralised faster in soils from enriched rings, suggesting a CO 2 -induced shift in the microbial biomass characteristics (structure, diversity, activity) and/or in the quality of the root-released organic compounds.", "keywords": ["580", "RHIZODEPOSITION", "0106 biological sciences", "2. Zero hunger", "RAY GRASS ANGLAIS", "MINERALISATION", "RHIZOSPHERE RESPIRATION", "04 agricultural and veterinary sciences", "[SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study", "15. Life on land", "01 natural sciences", "MICROBIAL BIOMASSE", "CARBON SEQUESTRATION", "0401 agriculture", " forestry", " and fisheries", "ELEVATED CO2", "[SDV.SA.SDS] Life Sciences [q-bio]/Agricultural sciences/Soil study", "NITROGEN FERTILISATION"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2005.06.023"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2005.06.023", "name": "item", "description": "10.1016/j.soilbio.2005.06.023", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2005.06.023"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2006-04-01T00:00:00Z"}}, {"id": "10.1093/jxb/erad421", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:17:15Z", "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.Data for manuscript The data provided in the present document corresponds to the manuscript: Engedal, T., Magid, J., Hansen, V., Rasmussen, J., S\u00f8rensen, H., Jensen, L. S. (2023): Cover crop root morphology rather than quality controls the fate of root and rhizodeposition C into distinct soil C pools. Global Change Biology, in press. Short abstract In order to investigate the fate of cover crop-derived belowground C as rhizodeposition and, over time, into the distinct soil organic carbon pools of particulate- and mineral-associated organic carbon (POC and MAOC), a column trial was esblished with 0.25 m top soil and 0.25 m sub soil. Four cover crops were grown for 3 months and 14CO2-labelled twice a week. Four out of eight replicate columns were destructively harvested to quantify root C and the carbon lost via rhizodeposition in absolute (qClvR) and relative terms (%ClvR) in bulk soil and rhizosphere soil from top- and subsoil (t1). The other four replicate columns were harvested for undisturbed incubation for one year, before final sampling (t2). Bulk soil from both sampling times were subject to a simple fractionation protocol by size, where particles larger from 50 microns were assigned to POC and smaller than 50 microns assigned to MAOC after dispersion in NaHMP. All fractions were dried, weighed and analyzed for 14C activity as disintegrations per minute (DPM). Further details Column ID 1-16 refer to columns sampled at t1, while column ID 17-32 refer to columns sampled at t2. Underlying assumptions and detailed descriptions of the different fractions are to be found in the manuscript.", "keywords": ["2. Zero hunger", "MOAM", "POM", "MAOC", "cover crop", "15. Life on land", "soil organic fractionation", "soil organic carbon", "mineral-associated organic matter", "rhizodeposition", "root morphology", "particulate organic matter", "root carbon", "POC"], "contacts": [{"organization": "Engedal, Tine, Magid, Jakob, Hansen, Veronika, Rasmussen, Jim, S\u00f8rensen, Helle, Jensen, Lars Stoumann,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.5281/zenodo.8090465"}, {"rel": "self", "type": "application/geo+json", "title": "10.5281/zenodo.8090465", "name": "item", "description": "10.5281/zenodo.8090465", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5281/zenodo.8090465"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2023-06-28T00:00:00Z"}}, {"id": "20.500.11850/645010", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:22:14Z", "type": "Journal Article", "created": "2023-10-26", "title": "Location: root architecture structures rhizosphere microbial associations", "description": "Abstract
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.