Nitrogen and phosphorus balances on Finnish dairy farms

Abstract

The calculation of whole-farm nutrient balance is an effective and simple method for estimating the potential nutrient loading from dairy farming into the environment. In Finland, however, the published results based on larger number of farms are still lacking. In this study whole-farm nitrogen (N) and phosphorus (P) balances on Finnish dairy farms were studied based on short-cut data for the year 2002. The survey was targeted to 1260 dairy farms, located all over Finland. Of the 386 replies received, 319 were used for subsequent statistical analyses. The association between selected farm variables and nutrient balance was studied using regression analysis and a sensitivity coefficient was calculated for each regression slope. The average (± standard deviation) whole-farm nutrient balance for N and P was 109 (±41.3) and 12 (±7.2) kg ha -1 , respectively. The most responsive factors affecting the nutrient balances were total nutrient and fertilizer import per ha, followed by animal density, milk export per ha and concentrate import per ha. The results suggested that nutrient surpluses could be controlled more easily in combined crop and milk than in specialised milk production. It is concluded that nutrient surplus on Finnish dairy farms is markedly lower than that on areas with intensive production in central European countries. However, when nutrient balances were extrapolated to comparable production intensity as in central Europe, the level of the surpluses was equal.

Evaluating Slurry Broadcasting and Injection to Ley for Phosphorus Losses and Fecal Microorganisms in Surface Runoff

“…The mean surplus of P was extremely high (32–36 kg ha −1 yr −1 ) on slurry‐amended plot areas, whereas the average P surplus in Finnish agricultural land was estimated to be 13 kg ha −1 yr −1 in the period 1995 through 1999 (Antikainen et al, 2005). Moreover, the farm gate balance for P has been found to be 12 kg ha −1 on dairy farms (Virtanen and Nousiainen, 2005; Uusi‐Kämppä et al, unpublished data). The amounts of P sources applied were high (52–79 kg TP ha −1 yr −1 ) during slurry years.…”

Ecological impacts of early 21st century agricultural change in Europe – A review

“…Early sown cover crops are likely to be effective at reducing N loss from freely draining sandy soils, with reductions varying between 29% and 91% compared to bare fallow, but cereal volunteers and/or the regeneration of weeds may be sufficient in poorer draining soils . Mixed farming can have a role in reducing on-farm nutrient surpluses: in combined crop and milk production in Finland they were easier to control than in specialised milk production (Virtanen and Nousiainen, 2005). Slurry storage capacity can also influence pollution by nutrients as more slurry is produced in the winter when livestock may be housed, rainfall is higher and the potential for leaching is greater.…”

Current and future prospects of milk quality from the Finnish dairy industry point of view

“…Both surpluses for N and P per land area tend to increase as the milk yield per land area increases (Figure 4). The current trend towards more intensive milk production whether expressed per cow or land area evidently increases the risk for environmental problems (Virtanen and Nousiainen, 2004). The increase in animal density associated to increasing herd size as well as feeding more concentrates and protein supplements are evident reasons for the lower N and P utilization efficiency at a farm level.…”

“…Dairy product traceability, raw milk contaminants (pesticides, heavy metals and microbial Figure 4. The effect of milk production intensity on the phosphorus (P) and nitrogen (N) balance (kg/ha) on Finnish dairy farms (data from Virtanen and Nousiainen, 2004) Milk yield, kg/ha P surplus, kg/ha N surplus, kg/ha N P toxins) and hygiene, health treatment of animals and feeds used for dairy cattle are of specific interest. Customers want even audit dairy farms and plants to ensure total product quality.…”