Transcript PowerPoint Sunusu

Dr. Selim KAPUR
University of Çukurova
Departments of Soil Science and Archaeometry
Adana, TURKEY
[email protected]
Mineral Soils conditioned by
Topography and Age
The development of the profile is limited by the erosion exceeding
soil formation or by the influence of topographic position
The Reference Soil Group of the Leptosols accommodates very
shallow soils over hard rock or highly calcareous material but
also deeper soils that are extremely gravelly and/or stony.
They are particularly common in mountain regions. Leptosols correlate
with the `Lithosols' taxa of many international classification systems
(USA, FAO) and with `Lithic' subgroups of other soils groupings. In
many systems, Leptosols on calcareous rock are denoted `Rendzinas';
those on acid rock are also called `Rankers'.
Erosion,
mass wasting,
drought,
flooding,
poor drainage, and
stoniness
Soils having
continuous hard rock@ within 25 cm
from the soil surface; or a mollic@
horizon with a thickness between 10
and 25 cm directly overlying material
with a calcium carbonate equivalent of
more than 40 percent, or less than 10
percent (by weight) fine earth from the
soil surface down to a depth of 75 cm;
and
no diagnostic horizons other than a
mollic@, ochric@, umbric@, or
yermic@ horizon.
Mollic A-horizon, surface horizon with dark color due to
organic matter; Base saturation exceeds 50%.
Ochric A horizon, surface without stratification and lacking
the characteristics of (A histic H-horizon, or) a mollic,
umbric or fimic A-horizon
Umbric, similar to a mollic A-horizon but base saturation
lower than 50%
Yermic, an A horizon with aridic properties and a
pavement that is varnished or includes wind-shaped
gravel or stones ("ventifacts"); or a pavement and a
vesicular crust; or a vesicular crust above a platy Ahorizon, without a pavement, or a biological crust, 1 -2 mm
thick.
Black mollic epipedon
http://soils.usda.gov/
Yermic epipedon
http://www.fsagx.ac.be/gp/desert-soil/index4.htm
Ochric epipedon
BASALT
LIMESTONE
Lithic Leptosol
http://www.soils.wisc.edu
Lithic (Chromic?) Leptosol
Calcaric Leptosols
Lithic,
Hyperskeletic,
Rendzic, Gelic,
Vertic, Gleyic,
Mollic, Umbric,
Humic, Aridic,
Gypsiric, Calcaric,
Yermic, Dystric,
Eutric, Haplic.
SOIL
PETROCALCIC HORIZON
CALCAREOUS ROCK
May be a shallow soil overlying calcareous material but a petrocalcic
horizon integrates it to a Calcisol, NOT A LEPTOSOL
Parent material Various kinds
of rock or unconsolidated
materials with less than 10
percent fine earth.
Environment: High or medium
altitude and with strongly
dissected topography.
Leptosols are found in all
climatic zones, particularly in
strongly eroding areas.
Profile development:
A(B)R or A(B)C
profiles with a thin Ahorizon. Many
Leptosols in
calcareous weathering
material have a mollic
A-horizon that shows
signs of intensive
biological activity with
a thin argic B.
From Tropics to the cold polar regions and
from sea level to the highest mountains.
Widespread in mountain areas,
Can be found on hard rocks or where
erosion has kept pace with soil formation or
removed the top of the soil profile.
Associations with other
Reference Soil Groups
Shallow soils with continuous hard rock within 25 cm from the soil
surface, excluding cemented layers such as a petrocalcic (laminar
calcium carbonate on rock or sediment = 50% by weight, root
penetration limited, extremely hard consistence when dry) or
petroplinthic (Fe cementation, OC less 0.6%, limited restriction)
horizon.
However, the definition includes also deeper soils, provided that
these have less than 10% fine earth over a depth of at least 75 cm.
WHEN DISCUSSING LINKAGES BETWEEN (DIVERSE!)
LEPTOSOLS AND OTHER REFERENCE SOIL GROUPS, ONE MIGHT
MAKE A DISTINCTION BETWEEN LEPTIC SOIL UNITS OF OTHER
REFERENCE SOIL GROUPS AND SOIL UNITS OF LEPTOSOLS.
Young soils, a thin A-horizon over an incipient B-horizon or
directly over the unaltered rock.
Presence of pedogenic differentiation despite the shallowness.
Integration to other soils is common, thus they occur as
associations ie undularting, mountainous, sloping soilscapes are
composed of integrates of Leptosols to;
I. Cambisols: with the development of a cambic horizon.
II. Andosols: if tephric soil material is present in profile
III. Podzols: The definition of the spodic horizon leaves
the possibility open that a full-fledged Podzol exists within the
depth limits of Leptosols. Such (mature!) soils are not Leptosols,
despite the presence of hard rock within 25 cm from the surface,
but are classified as (Leptic) Podzols.
IV. Luvisols: The definition of the argic horizon (a relict
Bt on the surface) precludes that an argic horizon can be present
within the depth limits of Leptosols, unless there is an abrupt
textural transition from the overlying horizon to the (more than
7.5 cm thick) argic horizon. In that case the soil is classified as a
(Leptic) Luvisol (or Acrisol or Lixisol, depending on CEC, clay
and base saturation).
V. Gleysols: "Gleyic properties" in Leptosols are exclusive to
(deeper) soils that qualify as Leptosols because they have less than
10 percent (by weight) fine earth to a depth of at least 75 cm.
"Stagnic properties" may have to be considered both in Leptosols
with continuous hard rock within 25 cm of the surface and in
Leptosols with less than 10 percent of fine earth to a depth of 75
cm, but Leptosols with stagnic properties have not been sufficiently
documented so far.
VI. Mollisols: A thin mollic epipedon overyling unalterned rock
particulary at mountaionus conditions under dense natural pasture
vegetation of Turkey most probably similar to the Rendzic units of
Spain, Italy, France, Albania, and Crotia qualifying as Leptosols
an A(B)R or A(B)C sequence
Rendzic (with white limestone fragments
and abrupt boundary to the rock) & Mollic
units more pronounced with dark brown
color or black calcareous organo-mineral
surface soil
Stable granular structure + vermicular
with earthworm activity
Blocky structure with increasing smectite
Free-draining soils with exceptions of
shallow groundwater.
Shallowness, stoniness, low water holding
capacity
Earthworms and enchytraeid worms are the chief
organisms important in carbon sequestration
enchytraeid worms
http://www.abdn.ac.uk
Earthworms
+A resource potential for wet-season grazing,
olive orchards, and vineyard.
Abandoned Roman Terraces inducing biodiversity and soil
development
+Human induced Erosion is the greatest threat. But natural
erosion is almost nil beacuse of vegetation cover coupled
with cracks with clay infills to retain water & inhibit
movement on bare karstic surface
+High population pressure (tourism), overexploitation and
increasing environmental pollution lead to increasing
deterioration of forests and threaten large areas of
vulnerable Leptosols.
Terrace walls on karstic landscape for water harvesting
+Man-made terraces for SLM allocated for grazing, grain and vineyard, olive,
carob, fig production on Chromic/Luvic Leptosols