Agriculture Reference
In-Depth Information
the local renewable flows are flow limited, then achieving this can alone
be achieved by reducing the emergy currently invested from society, F
(3808.2 × 10
14
seJ) to less than R (54.8 × 10
14
seJ), i.e., by a factor of 70.
Such an improvement seems out of reach without transforming the food
supply system. Some improvements can be made on the farm as indicated,
but the largest change will need to be in the society which determines
the emergy use per unit labor. It is important to note that for the standard
practices represented by the model system much larger reduction would
be required.
Emergy used for L&S accounts for 89% of total emergy fl ow and con-
stitutes by far the biggest potential for improvements. The L&S-compo-
nent refl ects the emergy used to support people directly employed on the
farm and people employed in the bigger economy to manufacture and pro-
vide the purchased inputs. Due to the high average material living standard
in UK with emergy use per capita being 8.99 × 10
16
seJ/year [50], labor is
highly resource intensive.
Emergy used for L&S can be reduced by reducing the revenue, but this
is highly undesirable. Nevertheless, the employees already have a relative-
ly low salary, which they accept because of the benefi ts enjoyed, e.g., free
access to vegetables, cheap accommodation on the farm perimeter and in
their opinion a meaningful job close to nature. Thus, the case system at-
tracts people with a Spartan lifestyle with few expenses and thus below
average emergy use.
In future, it is almost certain that the nation-wide emergy use per capita
will be reduced. A likely future scenario for the UK is that the indigenous
extraction of non-renewable resources continues to decline (down 23%
from 2.4 × 10
24
seJ in 2000 to 1.8 × 10
24
seJ in 2008 [50]). This is a result
of the oil extraction plunging from 2.6 to 1.5 million barrels per day (mbd)
from 2000 to 2008 (in 2010 further down to 1.1 mbd) [62]. In the same pe-
riod the extraction of natural gas dropped from 97.5 to 62.7 million tonnes
oil equivalent (and to 40.7 by 2010) [62]. This decline has been compen-
sated by increasing imports of fuels from 57 × 10
22
seJ in 2000 to 95 × 10
22
seJ by 2008 [50]. The UK has been able to maintain a high level of emergy
use per capita by gradually substituting the decline in oil and gas produc-
tion with imported fuels and services. Such a substitution may continue for
some years, but in a longer time perspective a decline in global production
