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AGRICULTURAL LAND CLASSIFICATION ABERGELE EAST (2011), CONWY ALC 001/2011 AGRICULTURAL LAND CLASSIFICATION SURVEY ABERGELE EAST (2011), CONWY CONTENTS 1. Agricultural Land Classification 2. References Map 1 Agricultural Land Classification AGRICULTURAL LAND CLASSIFICATION SURVEY ABERGELE EAST (2011), CONWY 1. AGRICULTURAL LAND CLASSIFICATION Introduction The original ALC map covering Wales was published in 1977 at a scale of 1:250 000 (one inch to four miles) and was marked ‘provisional’1. It shows the survey area to be predominantly Grade 2 agricultural land. The purpose of the provisional map is to provide broad-brush ALC, appropriate for strategic land use assessment. Additional and more detailed survey work is needed where site specific ALC is required. In response to a request from the Regional Planning Adviser, Welsh Assembly Government (WAG), the majority of the area was surveyed in detail during August and November 2007 (Map 1). In February 2011, an additional area was surveyed to the north east of the 2007 area, and outlined in red on Map 1. The 2011 survey only assessed the land outlined in red on Map 1. No additional survey work was carried out, or ALC grade boundary changes made, within the 2007 survey area. The purpose of both surveys was to assist in the agricultural evaluation of the site, to provide further information on its ALC Grade and to subdivide any Grade 3 land identified. The survey involved field sampling of soils at 100 metre intervals, together with interpretation of aerial photographs, examination of published geological2, climatic3 and soil data4,5,6. For clarity, the 2007 and 2011 survey areas have been combined into one map and report. Land Use The site covers approximately 60ha. At the time of the survey, the site was predominantly under grassland. a. PHYSICAL FACTORS AFFECTING LAND QUALITY i. Climate Average interpolated values for each climatic parameter as calculated for this site are listed below: Altitude Average Annual Rainfall (AAR) 7 - 70 m 724 - 770 mm Median Accumulated Temperature above zero degrees C, January to June (AT0) 1423 - 1457 Day °C Median Duration of Field Capacity Days (FCD) Moisture Deficit (Winter Wheat) Moisture Deficit (Potatoes) 171 - 180 Days 99 - 104 mm 88 - 95 mm The favourable combination of the Average Annual Rainfall and Accumulated Temperature values for this site meant it was not subject to any significant limitations in terms of overall climate. ii. Site The majority of the site was gently undulating, with gradients not imposing any significant limitation to agriculture. However, some areas, especially at the south of the site, contained gradients in excess of 7 degrees. This resulted in moderately severe limitations relating to gradient. A small enclosure to the west of Plas Isaf has severe limitations to agriculture due to micro-relief. iii. Soils A detailed survey of the site was carried out using a 120-centimetre Dutch type hand auger. Samples were taken at approximately 100 metre intervals on a grid basis. Representative soil pits were dug to supplement the auger boring information. Laboratory samples were taken to confirm topsoil textures. Soils on the site fell broadly into 2 types, both occurring across the site: Type 1 soils were typically composed of medium clay loam topsoils, overlying medium clay loam and / or sandy clay loam / fine sandy clay loam in the subsoil. Occasional subsoil horizons of heavy clay loam were noted and some profiles contained clay in the lower subsoil. Topsoil stone contents (>2cm diameter) were typically <5% by volume. Subsoils were typically not significantly stony, though some lower subsoil total stone contents (>2mm) were measured at 12% to 25% by volume. Type 2 soils were typically composed of medium clay loam topsoils, normally overlying medium clay loam in the upper subsoil with reddish clay below. The reddish clay commonly occurred below c.40 – 60cm from the soil surface. Stoniness was not a significant limiting factor in either topsoil or subsoil. iv. Soil Wetness Soils in Type 1 fell predominantly into Soil Wetness Classes (SWC) I & II. Wetness Class II soils typically contained gleying within 40cm from the soil surface. Soils in Type 2 fell predominantly into Soil Wetness Class III & IV. Wetness Class was largely dependent on depth to the slowly permeable reddish clay in the subsoil. The topsoil textures present, in combination with the number of Field Capacity Days (171 - 180) for this area, rendered the land subject to slight, moderate, or moderately severe agricultural limitations related to soil wetness and workability. v. Soil Droughtiness The combination of soil textures and structures present in Soil Types 1 & 2, related to the Moisture Deficit values for this area, meant soils in these types were typically not subject to significant limitations related to droughtiness. Occasional profiles were subject to slight limitations related to droughtiness. b. AGRICULTURAL LAND CLASSIFICATION Under the MAFF Agricultural Land Classification system, land is graded according to the degree to which certain physical characteristics - in particular climate, relief and soil - impose long-term limitations on agricultural use. A full description of the classification and of the criteria used in determining the gradings can be found in the published MAFF Report7. The areas of each Grade & Subgrade are delineated on Map 1, the reasons for grading are outlined below: Grade 2 Land has typically been mapped as ALC Grade 2 due to slight agricultural limitations relating to soil wetness and workability. Grade 3a Land has been mapped as ALC Subgrade 3a due to moderate agricultural limitations relating to soil wetness and workability. Subgrade 3b Land has been mapped as ALC Subgrade 3b chiefly due to moderately severe agricultural limitations relating to soil wetness and workability or gradient. Grade 4 Land has been mapped as ALC Grade 4 chiefly due to severe agricultural limitations relating to microrelief. Grades & Subgrades 1 and 5 did not occur within the survey area. Areas of land in each Grade and Subgrade ha % Agricultural Land % Total Land Grade 2 Subgrade 3a Subgrade 3b Grade 4 9.03 31.90 12.89 0.77 17 58 24 1 15 53 21 1 Total Agricultural Land 54.59 100 90 Non Agricultural Not surveyed 4.16 1.57 - 7 3 TOTAL SITE AREA 60.32 90 100 2. REFERENCES 1 MAFF (1977): 1:250 000 Series Agricultural Land Classification: Wales. 2 Geological Survey of Great Britain (England and Wales) (1970): 1:63,360 Map Series, Sheet 95 (Rhyl) – Solid & Drift. 3 Meteorological Office (1989): Climatological Data for Agricultural Land Classification. Met Office, Bracknell. 4 Soil Survey of England and Wales (1983): 1:250,000 Map Series, Sheet 2 (Soils of Wales), plus accompanying memoir. 5 Soil Survey of England and Wales (1960): Sheet 95 (Rhyl), 1:63,360, plus accompanying memoir. 6 MAFF/Soil Survey of England and Wales (1984): Soil Texture, Leaflet 895. 7 MAFF (1988): Agricultural Land Classification of England and Wales: Revised guidelines and criteria for grading the quality of agricultural land. Ian Rugg Sustainability and Environmental Evidence Division Welsh Assembly Government April 2011 Map 1 295000 Agricultural Land Classification ABERGELE EAST 2011 Grade Agricultural Land Quality Excellent 0.00 3a Good 31.90 4 Poor 1 2 377000 5 9.03 Very Good 3b 377000 Area (ha) 12.89 0.77 Moderate Very Poor 0.00 Urban 0.00 Other Land Categories W Non Agricultural 4.16 0.00 Woodland Agricultural Buildings 0.00 0.00 Open Water Not Surveyed 1.57 Total Agricultural Land Area 54.59 60.32 Total Survey Area Surveyed 2007 Surveyed 2011 160 80 0 160 Meters This map is based upon the Ordnance Survey Boundary Line data for The Welsh Assembly Government with the permission of Ordnance Survey on behalf of The Controller of Her Majesty's Stationery Office,© Crown Copyright. All rights reserved. Unauthorised reproduction infringes Crown Copyright and may lead to prosecution or civil proceedings. Licence Number 100017916. Cartography by TSD GI Unit, DEPC, Aberystwyth. © Crown Copyright 2007 295000 ALC Ref: 001/2011 Date: 06/04/2011