Download Soils of Britain

Did you know that, despite our modest land area and
limited range of cool, temperate climates, there are over
1,800 British soils types, each with a diversity of profiles.
Geologically, Britain has a wide range of rock types and
these generate diverse soil parent materials, ranging
from porous sands to impermeable clays and from acid
to alkaline. This variety increased over the past two
million years, when Britain’s climate fluctuated between
arctic Ice Ages and warm temperate conditions. Surface
materials were moved and sorted by ice, wind and
water. This resulted in many mixtures and combinations
of soil parent materials from different rock types.
Climatic swings also affected the topography and many
British landscapes were sculpted by ice and water.
The British Society of Soil Science
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“There is gradation in soils from warm dry lowlands
up to the cooler wetter highlands”
“In the lowlands, the Brown Earths, Gleys and the transitions
between have simple brown or grey profiles with variable
textures, drainage and contents of limestones”
“Shallow dark Rendzinas on chalk and limestone hills
are moderately productive arable soils”
“Artificial drainage of Gleysols and other lowland clays
improves their agricultural productivity making them
the main arable soils of Britain”
6
“In highland areas, slow decomposition of organic
matter and the lack of mixing by worms and
other soil animals produce Peats”
“Acid sandy parent materials develop brightly
coloured Podzol soils”
“Podzols and acid Peats have low agricultural
productivity, but non-acid Fen Peats are
very productive after drainage”
www.soils.org.uk
S.Hallett, I.Baillie, B.Kerr, L.Deeks, L.Hallett 2011
There is a climatic gradation of soils in Britain from the
warm dry lowlands in the south to the cooler, wetter
highlands in the north. Within this climatic pattern, soils
vary between rock types, and locally within landscapes
ranging from well-drained soils on crests and slopes to
imperfectly or poorly-drained valley soils. The British
soils we have today have also been much modified by
agricultural and industrial activities over the centuries.
“Varied rocks and Ice Age activity have developed diverse
soils in Britain”
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Soils of
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Great diversity on
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However, following drainage, non-acid lowland
peats can be highly productive and the Fen
Peats of Eastern England form some of the most
important horticultural soils in Britain supplying
many of the market garden crops.
Gleysols have impeded drainage, occurring
on lower slopes and valleys. They have simple
profiles with dark topsoils over wet grey subsoil,
often mottled rusty brown. In really wet sites
the mottles disappear with depth and the greys
become faintly bluish or greenish. These soils
often have high clay content. Gleys form where
water fills the soil pores and blocks off air flow.
The lack of air transforms iron from rusty oxides
to paler forms. The rust mottles form in pockets of
better aeration.
Rendzinas
Lowland
soils
Cambisols, or Brown Earths, are the dominant,
well-drained lowland soils, and are also
common at lower altitudes in the west. They
have simple profiles: dark brown topsoils over
lighter brown subsoils. The colouring is due to
worms which break up plant litter, dragging it
into the soil, thus mixing organic matter down
into the profile. Some Cambisols have reddish
or yellowish tinges inherited from different
source rocks. Textures range from sandy to
heavy clays. Clay content usually increases
from top- to subsoil. Some Cambisols contain or
overlie limestone, others can be acid.
Rendzinas are shallow, dark soils that occur
on chalk downland and other limestone
hills. Limestone dissolves in rainwater and
so weathering leaves little material for soil
formation. The profile consists of a few
decimetres of mixed organic matter, chalk
fragments and limited amounts of impurities and
windblown imports.
The productivity of most Gleys and some Brown
Earths with high clay content increases after
artificial drainage. The modern agricultural
landscape of lowland Britain owes much to
land drainage over the past three centuries.
Field drainage is an often under-appreciated
infrastructural legacy that now needs continued
maintenance and improvement. Once drained,
many naturally slow-draining Gleys and Brown
Field drainage and the use of
Lowland soils
Use of Peats and
Podzols
Podzols and most peats make poor agricultural
soils. Peats need drainage and lime. Podzols need
lime and fertilisers. These soils are therefore
mostly used for rough grazing, game rearing
and recreation. Podzols are also used widely for
coniferous plantations.
Brown earths
Podzols have highly colour-contrasted soil profiles,
from black topsoils through bleached white, with
a thin black layer over bright rusty brown or
orange, to yellowish brown. Podzols often form
in freely drained, sandy acid parent materials.
Acids from organic topsoils leach iron from the
bleached upper subsoil, redepositing it as a
bright rusty lower layer.
The dominant features of natural soil formation
in lowland soils are mixing by worms and other
small soil animals, moderate leaching, variable
drainage, and variable contents of chalk and
other limestones.
Gleys
Peats
Histosols, such as peats form where slow
decomposition and lack of mixing give deep
organic layers on top of mineral profiles. The
key factor here is waterlogging. In wet areas
throughout Britain, including the Fens, this results in
basin peat formation. In the wet highlands, peat
develops in a wide range of sites and can so
’blanket’ entire landscapes.
Podzols
Highland
soils
Cool, wet highland climates affect soil formation
by slowing down decomposition of plant litter and
organic matter, and by the processes of leaching
and acidification. This results in wet soils with dark
organic topsoils and low nutrient fertility. Such
mountainous regions may also have shallow, rocky
soils.
Earths can be very productive, representing the
main arable soils of Britain.
Rendzinas used to be important agricultural soils
in prehistoric times but then became neglected as
heavier soils became more accessible. Rendzinas
were mostly used for grazing sheep, but many
were also ploughed for cereal production from
the mid 20th century. This was prompted by the
needs of domestic food security in World War
II. These soils do not need drainage, tending to
be droughty, but crops can extract a degree
of moisture from the fractured, underlying
limestone rock.