best available technologies for manure treatment - Baltic Green Belt

Best Available Technologies for manure treatment baltic sea 2020
1: INTRODUCTION AND BACKGROUND DESCRIPTION
1: INTRODUCTION AND BACKGROUND DESCRIPTION
1.1: Background
Leaching of nutrients from sites with intensive
rearing of livestock, also known as agricultural hot
spots, has been identified by the Helsinki Commission
as a prioritized area. Data shows that the amount
of Phosphorous (P) and Nitrogen (N) in livestock
manure spread on agricultural land by EU Member
States in the Baltic Sea catchment area is 3–4 times
higher than the amounts discharged from all households
in the same area.
Consultations have been done on the value and
potential for Baltic Sea 2020 to address manure
handling at intensive livestock farming with e.g.
HELCOM, Swedish Institute of Agricultural and Environmental
Engineering (JTI), Swedish University
of Agricultural Sciences (SLU), Swedish Environmental
Research Institute (IVL) and the Federation for
Swedish Farmers (LRF). There is concordance on the
importance to reduce nutrient leakage from intensive
livestock farms to the Baltic Sea, through technical
development and spreading of “Best Practices”.
Baltic Sea 2020 has initiated a project to identify
Best Available Technologies to reduce leaching of nutrients
from farms with intensive rearing of pigs. The
target area of the project is EU Member States of the
Baltic Sea area: Sweden, Denmark, Poland, Germany,
Finland, Estonia, Latvia, and Lithuania.
Based on analyses of current projects and activities,
existing EU legislation and with consideration
to the sources of origin of N and P leaching to the
Baltic Sea, the report focuses on:
• Pig production in herds of more than 2.000 pigs
• Technologies for manure treatment rather than
practices for manure storage and spreading
• Denmark and Poland’s parts of the Baltic Sea
river basin area
1.2: Turnover of N and P in the
agricultural environment
When focusing on the N and P in livestock manure it
is important to clarify the process stage from animal
to final disposal. Figure 1 indicates via indexes the typical
retention of N and P in agricultural production
systems that respect good agricultural practices – the
rest is generally lost to the environment.
N is lost to the environment both via emissions,
leaching and run-off. Typically the emissions are
relatively high in pig stables, but emissions can also
happen from manure storages and in connection
with spreading. Run-off happens if manure is spilled
on the ground, if the floors in stables and the walls
and floors of the manures stores are not water tight,
if there is a long time span between spreading of
manure on the fields and the incorporation into the
soil, or if livestock manure is spread on steep, frozen
or water saturated soils.
Nitrogen (N) leaching from livestock manures happens
especially as percolation through soil layers
when it is applied on fields in an imprecise way, not
being based on norms and fertiliser planning, or
when it is distributed to bare soils or in any case at
periods, ways and situations where the nutrients are
Index of N amount: 100 80 75 50
Phase:
Manure leaving
animal
Manure leaving
stable
Manure leaving
storage
Re-circulated in the
crop
Index of P amount: 100 95 90 85
Figure 1: Recirculation of N and P in the agricultural production, based on Poulsen & Kristensen (1998) and Birkmose
et al. (2007) as concerns manure leaving animal, stable and storage, while indications for P as well as amounts
re-circulated in the crop largely are own estimates in situations, where good agricultural practices are applied.
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