{"type": "FeatureCollection", "features": [{"id": "10.1046/j.1365-3040.2002.00831.x", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-27T16:18:35Z", "type": "Journal Article", "created": "2003-03-12", "title": "N-2 Fixation By Acacia Species Increases Under Elevated Atmospheric Co2", "description": "Abstract<p>In the present study the effect of elevated CO2 on growth and nitrogen fixation of seven Australian Acacia species was investigated. Two species from semi\uffe2\uff80\uff90arid environments in central Australia (Acacia aneura and A. tetragonophylla) and five species from temperate south\uffe2\uff80\uff90eastern Australia (Acacia irrorata, A. mearnsii, A. dealbata, A. implexa and A. melanoxylon) were grown for up to 148\uffe2\uff80\uff83d in controlled greenhouse conditions at either ambient (350\uffe2\uff80\uff83\uffc2\uffb5mol\uffe2\uff80\uff83mol\uffe2\uff88\uff921) or elevated (700\uffe2\uff80\uff83\uffc2\uffb5mol\uffe2\uff80\uff83mol\uffe2\uff88\uff921) CO2 concentrations. After establishment of nodules, the plants were completely dependent on symbiotic nitrogen fixation. Six out of seven species had greater relative growth rates and lower whole plant nitrogen concentrations under elevated versus normal CO2. Enhanced growth resulted in an increase in the amount of nitrogen fixed symbiotically for five of the species. In general, this was the consequence of lower whole\uffe2\uff80\uff90plant nitrogen concentrations, which equate to a larger plant and greater nodule mass for a given amount of nitrogen. Since the average amount of nitrogen fixed per unit nodule mass was unaltered by atmospheric CO2, more nitrogen could be fixed for a given amount of plant nitrogen. For three of the species, elevated CO2 increased the rate of nitrogen fixation per unit nodule mass and time, but this was completely offset by a reduction in nodule mass per unit plant mass.</p>", "keywords": ["0106 biological sciences", "0301 basic medicine", "2. Zero hunger", "Acacia mearnsii", "Elevated atmospheric CO2", "Aneura Acacia", "Acacia", "growth response", "15. Life on land", "01 natural sciences", "Acacia dealbata", "Relative growth rate", "03 medical and health sciences", "nitrogen fixation", "Acacia aneura", "Nitrogenase", "Keywords: carbon dioxide enrichment", "Acacia melanoxylon"]}, "links": [{"href": "https://doi.org/10.1046/j.1365-3040.2002.00831.x"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Plant%2C%20Cell%20%26amp%3B%20Environment", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1046/j.1365-3040.2002.00831.x", "name": "item", "description": "10.1046/j.1365-3040.2002.00831.x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1046/j.1365-3040.2002.00831.x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2002-03-21T00:00:00Z"}}, {"id": "10.4236/ajps.2014.56101", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-27T16:22:19Z", "type": "Journal Article", "created": "2014-03-25", "description": "The aim of the work was to evaluate the productivity, leaf nutrient content and soil nutrient con- centration in maize (Zea mays L.) grown in sequence with black oats (Avena strigosa Schreb.) under Leucaena diversifolia alley cropping agroforestry system (AFS) and traditional management system/sole crop (without trees-TS), after two years of cultivation following a randomized block design. The experiment was carried out in the Brazilian Association of Biodynamic Agriculture, in Botucatu\u2014Sao Paulo, Brazil. Treatments were: control (C), chemical fertilizer application (F), biomass of L. diversifolia alley cropping application (B), biomass of L. diversifolia alley cropping + chemical fertilizer application (B + F). In the second year of management it was observed that black oat yield was higher in treatments B + F and F with significant difference in relation to the others treatments in both systems, followed by treatment B. Between systems, only treatment B showed significant difference, with higher yield value corresponding to AFS, reflecting the efficien- cy of AFS to promote soil fertility. Maize production presented the second year of cultivation an increasing trend in all treatments in both production systems. This result may be due to the cumu- lative effect of mineralization and maize straw and oats, along the experiment. How productivity was higher in the AFS system, could also be occurring effect of biological nitrogen fixation, water retention and reduction of extreme microclimate through the rows of L. diversifolia. Comparing the AFS and TS, it was observed that the concentration of N in leaf tissue was higher in the AFS treatments, probably due to nitrogen fixation performed through the rows of L. diversifolia, that is a nitrogen fixing tree species. After two years, carbon stocked in soil show higher values in the treatments biomass + fertilizer and biomass application, in both systems, AFS and TS. * Corresponding author.", "keywords": ["2. Zero hunger", "Agroforestry system", "Mineral nutrition", "0401 agriculture", " forestry", " and fisheries", "04 agricultural and veterinary sciences", "15. Life on land", "Acacia melanoxylon", "630"], "contacts": [{"organization": "Bertalot, Maria Jos\u00e9 Alves, Guerrini, Irae Amaral, Mendoza, Eduardo, Pinto, Mauro S. V.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.4236/ajps.2014.56101"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/American%20Journal%20of%20Plant%20Sciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.4236/ajps.2014.56101", "name": "item", "description": "10.4236/ajps.2014.56101", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.4236/ajps.2014.56101"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2014-01-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Acacia+melanoxylon&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Acacia+melanoxylon&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Acacia+melanoxylon&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Acacia+melanoxylon&offset=2", "hreflang": "en-US"}], "numberMatched": 2, "numberReturned": 2, "distributedFeatures": [], "timeStamp": "2026-07-27T18:06:19.797180Z"}