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Uusitalo, Risto; Turtola, Eila; Grönroos, Juha; Kivistö, Juhani; Mäntylahti, Väinö; Turtola, Ari; Lemola, Riitta; Salo, Tapio. |
Soil test phosphorus (P) concentration has a major influence on the dissolved P concentration in runoff from agricultural soils. Thus, trends in soil test P partly determine the development of pollution potential of agricultural activities. We reviewed the changes of soil test P and P balances in Finnish agriculture, and assessed the current setting of P loss potential after two Agri-Environmental Programs. Phosphorus balance of the Finnish agriculture has decreased from +35 kg ha–1 of the 1980’s to about +8 kg P ha–1 today. As a consequence, the 50-yr upward trend in soil test P concentrations has probably levelled out in the late 1990’s, as suggested by sampling of about 1600 fields and by a modelling exercise. For the majority of our agricultural soils,... |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover. |
Ano: 2007 |
URL: http://orgprints.org/17083/1/uusitalo.pdf |
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Salo, Tapio; Turtola, Eila. |
In the Finnish conditions, annual N leaching from the experimental plots was not adequately estimated using the respective annual N balances, or supplementing the estimation with annual precipitation, total runoff, or drainage runoff (Salo and Turtola, 2006). Values averaged over the years improved the estimation when management included such environmentally risky managements as bare fallow or off-season application of cow slurry (Salo and Turtola, 2006). Calculated with the linear regression (Salo and Turtola, 2006), N leaching was 20-57 % of the averaged N balance. |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Air and water emissions. |
Ano: 2008 |
URL: http://orgprints.org/15808/1/longterm1.pdf |
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Salo, Tapio; Lemola, Riitta; Esala, Martti. |
Nitrogen (N) balance has been identified as a principal agri-environmental indicator. In addition to national N balances, calculation of N balances for different agricultural regions is also recommended. In this study, national and regional net N balances for Finland were calculated. The net N balance is the result of deducting the NH3-N losses from manure and fertilisers from the gross N balance. The N balance calculation was based on data for Finnish Rural Centres and calculated per cultivated hectare. The main data inputs for the calculations were agricultural and environmental statistics, coefficients of manure excretion and crop N concentrations. Finnish national net N balance decreased from 90 kg ha–1 in 1990 to 50 kg ha–1 in 2005. The decrease in... |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover. |
Ano: 2007 |
URL: http://orgprints.org/16896/1/salo.pdf |
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Rankinen, Katri; Salo, Tapio; Granlund, Kirsti; Rita, Hannu. |
Nitrogen (N) gross balance is one of the indicators designed for following developments in agriculture in the European Union. A nutrient surplus occurs when the quantity of a nutrient applied in fertilizers is greater than that removed during harvest. In this study the usefulness of N balance in studying the fate of N and controlling N leaching from agricultural fields in south-western Finland was evaluated. To estimate N leaching in 2000–2005 the mathematical, process-based model COUP was applied to twelve fields representing four agricultural production sectors. The fields represented conventional cereal production, organic cereal production and both conventional cattle and pig husbandry. Simulated N leaching was lowest from cereal production fields with... |
Tipo: Journal paper |
Palavras-chave: Air and water emissions. |
Ano: 2007 |
URL: http://orgprints.org/16899/1/rankinen.pdf |
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