Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2022
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Abstract
Enhancing carbon storage in managed soils through increased use of cover and catch crops in cereal cropping is at the heart of a carbon-negative agriculture. However, increased C storage by additional biomass production has a nitrogen cost, both in form of increased N fertilizer use and by potentially increasing nitrous oxide (N2O) emissions when cover crops decay. Frost-sensitive, N-rich aboveground biomass may be a particular problem during wintertime, as it may fuel off season N2O emissions during freezing-thawing cycles, which have been shown to dominate the annual N2O budget of many temperate and boreal sites. Here we report growing season and winter N2O emissions in a plot experiment in SE Norway, testing a barley production system with seven different catch and cover crops (perennial and Italian ryegrass, oilseed radish, summer and winter vetch, phacelia and an herb mixture) against a control without cover crops. Cover crops where either undersown in spring or established after harvesting barley. While ryegrass undersown to barley marginally reduced N2O emissions during the growing season, freeze-thaw cycles in winter resulted in significantly larger N2O emissions in treatments with N-rich cover crops (oilseed reddish, vetch) and Italian ryegrass. N2O budgets will be presented relative to aboveground yield and quality of cover crops and compared to potential souil organic carbon gains.
Abstract
No abstract has been registered
Academic – Long-term grassland productivity with and without ploughing
Ievina Sturite, Samson Øpstad
Abstract
Several studies conclude that permanent and temporary swards are equally productive, given equal management. In Norway, one experimental field trial has been maintained since 1974 (Fureneset; 61°18’N, 5°4’E). This ongoing experiment includes long-term/permanent ley (no-tillage over 25 and 45 years) next to temporary leys reseeded regularly. The objective of the study was to test reseeding/ renovation methods that may maintain long-term forage productivity. We hypothesized that sod seeding after chemical fallowing improves grassland productivity equally to that from reseeding after ploughing. In 2017, the frequently ploughed treatments, and half of the 25-year-old sward, were renewed by ploughing and reseeding with grass-clover seed mixtures. The second half of the 25-year-old sward was chemically fallowed and sod-seeded. The treatments included three different fertilizer strategies: mineral fertilizer (210 N kg ha-1) and cattle slurry in combination with mineral fertilizer (210 and 340 kg total-N kg ha-1). On average for four production years (2018-2021) the dry matter yield (DMY) of permanent sod-seeded 25-year-old ley was about 11 t ha-1, and these yields were equal to swards renewed by ploughing and reseeding.