Samson Øpstad
Research Scientist (OAP Agreement)
(+47) 406 21 871
samson.opstad@nibio.no
Place
Fureneset
Visiting address
Fure, 6967 Hellevik i fjaler
Authors
Alice Budai Daniel Rasse Thomas Cottis Erik J. Joner Vegard Martinsen Adam O'Toole Hugh Riley Synnøve Rivedal Ievina Sturite Gunnhild Søgaard Simon Weldon Samson ØpstadAbstract
No abstract has been registered
Abstract
More than 2/3rds of Norway’s agricultural area are grassland, and more than half of it is over 5 years old. Renewing old grassland increases annual yield but causes yield loss during renewal. Parts of the increased yield is due to replacement of low-productive species with high production species and cultivars, replacing biodiversity with productivity. Finding the optimal rate of renewal requires long term experiments to compare the sustainability of different strategies. Therefore, three field experiments were established to investigate the effect of difference renewal and harvest strategies on grass yield and quality, on similar mineral soil at Særheim (58.5°N, 5.6°E) in 1968 and Fureneset (61.3°N,5.0°E) in 1974, and on peat soil at Svanhovd (69.5°N,30.0°E) in 1968. Until 1991, the experiment included non-renewed treatments, and renewal every 3rd or 6th year. It was cut either two or three times a year, with autumn grazing on parts of the two-cut regime. The experiment was simplified in 1992, with the establishment of another non-renewed treatment, all treatments being cut 3 times a year (2 at Svanhovd), no grazing but contrasting slurry and compound fertilizer applications. This phase lasted until 2011, followed by period with no renewal and minimal registration. The third phase started in 2016, with renewal of all treatments at Fureneset and Særheim, except the permanent grassland from 1968/1974. Duration between renewals was doubled, and fertilizer applications revised. Presenting results from the third phase, we show that five to six years are required to recoup and significantly over-yield the non-renewed grassland. We will use soil chemical and physical properties, fertilizer application and yield gaps as well as ecological succession from sown seed mixture in 2017 till 2022 grassland to discuss the why we needed six years for all renewed treatments to over-yield permanent grassland from 1974.
Authors
Alice Budai Daniel Rasse Teresa Gómez de la Bárcena Hugh Riley Vegard Martinsen Ievina Sturite Adam Thomas O'Toole Samson Øpstad Thomas CottisAbstract
No abstract has been registered