two very different glacial tills in the northeast of ireland. 18.05.10

‘‘Two Very Different Glacial Two Very Different Glacial Tills in the Northeast of Tills in the Northeast of

Ireland’Ireland’

Padraic MulroyPadraic Mulroy

Environmental PedologyEnvironmental Pedology

Glaciation –Glaciation –

1. Midlandian1. Midlandian10,000-70,000bp10,000-70,000bp

2. Munsterian2. Munsterian100,000- 100,000-

125,000bp125,000bp

SITE 2SITE 1SITE 1SITE 1SITE 1

SITE 2SITE 1

Regional ClimateRegional Climate

Mean Annual Temperature -8.8°C Mean Annual Temperature -8.8°C (48°F) (48°F)

Mean Annual Soil Temperature - Mean Annual Soil Temperature - 9.7°C (49.5°F) 9.7°C (49.5°F)

Total Annual Rainfall - 928mmTotal Annual Rainfall - 928mm Total Annual ET - 400mmTotal Annual ET - 400mm

Soil 1. Podzolic GleySoil 1. Podzolic GleyVariantVariant

SITE

TP1

TP1TP1TP1

SLOPE

TP1

TP2

TP3

Natural vegetationNatural vegetation

• Grass – pastureland

for beef cattle on raised

areas, intensive shallow

drainage network

• Rushes – low lying

waterlogged areas or

‘troughs’ or peaty areas

•Hedgerows –

Hawthorn, Blackthorn,

ash

TP1TP1TP2TP2TP3TP3

Facing Facing EastEast

Ap horizon - 0 – 0.42m Texture - clay loam to clay Color – 10 YR 5/4Boundary - smooth wavyStructure – fine/medium crumb & granular structure

E1 horizon – 0.42 – 0.95mTexture - gravelly gritty loam Color – 5 Y 7/3 -6/3Boundary – smooth wavyStructure – subangular, blockyOrange mottling at bottom interface

2Oeb horizon – 1.75 – 1.90mTexture - organicColor – 10YR 2/1 to 4/2Boundary - smoothStructure – Moderate to fine crumbSome twigs and roots visible

Bsg1 horizon – 1.05 – 1.40mTexture - clay (silt lenses)Color – Gley 2 5/1Boundary -smooth (no colour change)

Structure – almost massive

Bg2 horizon – 1.40 – 1.75mTexture - clay Color – Gley 2 6/1Boundary – abrupt wavy Structure – massiveSome root fibres

LAND LAND DRAINDRAIN

TP1TP1

Eg2 horizon – 0.95 – 1.05mTexture - gravelly gritty loam Color – 10 YR 6/6Boundary – diffuse wavyStructure – subangular, blocky

OCHRIC

CAMBIC

2Bhb horizon – 1.9 – 2.85mTexture – peaty silt Color – 10YR 4/2Boundary - GradualStructure – blocky to massive

2C1gb horizon – 2.85 – 3.4mTexture – clayey loamColor – Gley 2 7/2Boundary - GradualStructure – blocky to massive

2C2gb horizon – 3.4 – 4.05mTexture – siltColor – Gley 2 8/2Boundary – abrupt/unclear – not sightedStructure – massivev. soft, melted butter, v. sticky, dilatant

TP2TP2

Soil PropertiesSoil Properties

• Infiltration – Low

• Available water - Moderate

• Hydraulic Conductivity – Low

• Soil Wetness Class – Class 5

(<25cm bgl)

Soil CharacteristicsSoil Characteristics

• Infiltration – Footslope

• Parent Material – Sandstone &

shale

• Soil slope – Sloping 6.5%

• Surface run-off – ponded

• Erosion Potential – very low

Diagnostic HorizonsDiagnostic Horizons

• Epipedon - Ochric

• Subsurface Horizon - Cambic

=> INCEPTISOL

Soil 2. Brown EarthSoil 2. Brown Earth

TP1TP1

TP1

Natural vegetationNatural vegetation

• Grass pastureland

for beef cattle

• Tillage –

barley, oats, etc

• Broadleaved

Hedgerows –

Oak, Ash, etc

TP1TP1

Facing Facing SoutheastSoutheast

TP1TP1Ap horizon - 0 – 0.2m Texture - gravelly channery loam Color – 10 YR 3/2Boundary - v. diffuse irregularStructure – coarse crumb to subangular blocky

Bw or A2 horizon – 0.2 – 0.33mTexture - channery loamColor – 7.5YR 5/6Boundary - diffuse irregularStructure – subangular blocky

C horizon – 0.33 – 1.55mTexture - sandy loamColor – 10YR 5/6Boundary – diffuse irregularStructure – crumb/subangular blocky

R horizon – 1.55 – 3.5mTexture – weathered sandstone

Angular greywack

e sandstone

Subangular red

sandstone

Angular channers (shale)

Subrounded pebble

(granite)

Glacial till depositsGlacial till deposits

Subrounded & subangular Channers (limestone)

Soil PropertiesSoil Properties

• Infiltration – High

• Available water - Low

• Hydraulic Conductivity –

Moderate/High

• Soil Wetness Class - Class 1 (>150cm

bgl)

Soil CharacteristicsSoil Characteristics

• Infiltration – Upland (near apex of

hill)

• Parent Material – Sandstone &

shale

• Soil slope – Sloping 10.5%

• Surface run-off – Medium

• Erosion Potential – High

Diagnostic HorizonsDiagnostic Horizons

• Epipedon - Ochric

• Subsurface Horizon – Cambic

=> INCEPTISOL

Diagnostic HorizonsDiagnostic Horizons

• Epipedon - Ochric

• Subsurface Horizon – Cambic

=> INCEPTISOL

Thank YouThank You