Zentralstelle der Forstverwaltung - Landesforsten Rheinland-Pfalz

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9 Summary
organization of the soil inventory and methods
the national forest soil inventory (bze) of Germany
is a project in cooperation between the
federal Government and the German states. the
investigations of the bze i and bze ii were prepared
and coordinated with a great effort by a task
force of the federal Government and the German
states.
the fieldwork and soil sampling in Rhineland-
Palatinate for bze i was done in the years
1989/1990 and for bze ii seventeen years later
in 2006/2007. for both investigations the survey
was performed at the intersections of a 4x12 kmgrid
and also at the random sample points of the
16x16 km-grid of the european union being allotted
to Rhineland-Palatinate. the points of the annual
crown condition assessment and the points
of the forest nutrition assessment which was
carried out parallel to the bze are located at the
same grid. the bze is part of the forest environment
monitoring, which the research group 6.2
„forest Monitoring and environmental Provision"
of the Research institute for forest ecology and
forestry (faWf) is responsible for in Rhineland-
Palatinate. the bze ii was performed in close cooperation
of the faWf with the forest inventory
and site assessment department of the Central
forest authority, the department of Waste management,
Residual Waste and soil Protection of
the former Ministry for environment, forests and
Consumer Protection, the state office for Geology
and Mining and the agricultural investigation
and Research institute speyer.
the used methodology corresponds to a large
extent to the field manual created by the bze
task force. state-specific differences are described
in detail in the present report. the evaluation of
the bze results were carried out according to the
proposals in Riek and Wolf (2007) and ak standortskartierung
(2003).
Representativity of the random sample grid
143 points were selected for the bze i and 165
points for the bze ii. the bze ii grid represents
well the important stratigraphic-petrographic
units of „slate", „quartz rich sandstones of the
devonian" and „quartzitic bound triassic sandstone",
as well as the comparably frequently occurring
substrates „Permian siltstones (Rotliegend)
and „Magmatite (igneous rocks)". „Quaternary
cryogenic substrates” are underrepresented and
„Quaternary allochthonous sediments" overrepresented.
soil acidification
the ph-values, the cation exchange characteristics,
the carbonate content, the anion content
in 1:2 soil-water extracts and the exceedance
of the critical load for acidity were used for the
description of the status and the change of the
acid-base state of the forest soils. the majority of
the grid points show a clear rise in soil ph down
to the subsoil between bze i and ii. at the time
of bze i more than two thirds of the sites showed
top soil ph of the aluminium and iron aluminium
buffer range, at the time of bze ii the majority
was found in the cation exchange buffer zone.
this corresponds with changes in the amount of
the exchangeable cations. a significantly increase
in base saturation until a soil depth of 60 cm is
found in the bze ii data compared to the results
of the bze i. the number of grid points, where
the uppermost mineral soil layer was classified
as „very low" and "low" for base saturation, has
been reduced by more than half from bze i to
bze ii. the improvements in the acid-base status
of the soils affect particularly sites and regions in
which before especially low ph-values and base
saturation were found, like the new Red sandstone
sites in the Palatinate forest and the Quartz
rich sites in the hunsrück. basically this might be
explained by large-scaled compensation liming in
this regions.
the analysis results of the 1:2 extracts show a
clear decrease of the sulphate concentrations
between the bze i and the bze ii, which corresponds
with the clear decrease of the atmospheric
sulphate deposition. on the other hand no
significant changes were found for the nitrate
concentrations between the results of both investigations.
the deposition of potential acids calculated by