Agriculture Reference
In-Depth Information
(Granstedt, 2000). The greater part of the minerals is recycled within the farm in the
manure. The limited net export of phosphorus and other nutrients seems to be
compensated by the weathering processes in most soils and a recycling of food residues
could further decrease these losses from the system (Granstedt, 2000; Granstedt and
Kjellenberg, 2011). The strive to be self-sufficient in fodder limits the number of animals
per hectare. In reality, however, some smaller amounts of imported inputs (seeds, fodder
and rock powder for soil improvements) can be necessary depending on variation in
yield level between different years. An external fodder rate of a maximum of 15% of total
fodder and an animal density of <0.75 animal units/ha were used as criteria for selecting
ERA-farms (Granstedt, 2005). An animal unit (au) is defined as one dairy cow, or two
young cows, or three sows, or ten fattening pigs, or 100 hens. By following these
principles nutrient in manure does not exceed what can be utilised by crops during the
crop rotation in the same system. Each single farm does not need to function as a closed
system. Farms in the same region with complementing production could cooperate and
together function as a recycling farming system in terms of fodder and manure, but
regional specialisation of production is problematic. The studies are based on calculated
surplus and emissions of reactive nitrogen and surplus of phosphorus compounds from
the agriculture-society system according to methods developed by Granstedt (1995; 2000;
2005).
i
Adapted from Larsson and Granstedt (2010).
Box 1. Principles of ecological recycling agriculture systems
i
2.1 The consumer survey and calculating an alternative food basket
A consumer case study was carried out in Järna, a community of around 7500 inhabitants.
Järna is part of Södertälje municipality, located in Stockholm County. Järna was chosen
because there are numerous biodynamic and organic farms and market gardens in the area
that serve the local market and a well developed consumer network linked to these farms,
i.e. it was possible to find a group of environmentally concerned consumers that was willing
to take part in the survey. There are also several food processing industries like a mill and
bakery (with both a local and national market), a farm-size dairy and a farmer cooperative
selling organic vegetables and meat. For a more detailed presentation of the site see Haden
and Helmfrid (2004) and Wallgren (2008).
The families participating in the survey recorded their food purchases for two two-week
periods in 2004; one in winter/spring (when local products are scarce) and one in late
summer/early autumn (when local products are easy available). The periods were chosen in
order to get representative results for the yearly consumption. Information on the amount,
price, origin and environmental brand (e.g. Demeter or KRAV)
3
of all food products was
recorded either on the detailed receipts or on specified lists supplied. Since the matter of
concern in the study was environmental impacts from food and local production, and the
studied farms only produce “real food”, only these types of products were included in the
consumer study. Products such as sugar, candy and beverages were thus not included.
After the recording period, the families were interviewed about their food choices, food
consumption and food purchasing habits. The amounts of different products purchased
3
KRAV is the certifying organisation of organic products in Sweden and Demeter is the equivalent for
biodynamic products. See www.krav.se and www.demeter.nu.
Search WWH ::
Custom Search