On this page you will find:
- Minerals and Soils Overview
- Key Facts and Figures
- Sustaining the Landscape
- Soils
- Management Influences and Forces for Change
- Policies and Priorities
Minerals and Soils Overview
Minerals
Mineral use in the Isle of Wight AONB can be traced back to the use of flint deposits by Palaeolithic people through to recent industrial extraction. Disused quarries, lime kilns, vernacular architecture, standing stones are all testament to the significance of minerals.
The AONB continues to provide an important finite resource for minerals such as chalk, gravel, clay, and sand. The Isle of Wight Council as Mineral Planning Authority details current and expected extraction and sets out policies that seek to safeguard sites of importance for geology, geomorphology, nature conservation, archaeology, historic environment and landscape value 68
Soils
Soil is a basic, limited resource that is essential for many human activities. It includes topsoil and subsoil to the depth of at least one metre. The biological, physical, and chemical characteristics of soil need to be protected for it to perform its important functions, including the essential minerals required to produce food, raw materials and energy. Soils provide a filtering and buffering action to protect water and the food chain from potential pollutants; they help to maintain gene pools and wildlife populations; and often cover historic and archaeological sites containing artefacts and historical indicators such as pollen. All soils need to be sustainably managed for the long term.
Wealden clay produces heavy soils and where it occurs inland, it mostly supports pasture. The light sand soils over the Lower Greensand provide some of the best arable land on the Island. The Chalk gives rise to thin lime-rich soils, which supports distinctive vegetation.
Key Facts and Figures
Sustaining the Landscape
Land-won aggregates on the Isle of Wight relate to sand, gravel and brick clay with some local level chalk extraction. In 2021, 117,539 tonnes of sand and gravel were land-won from the Island, greater than the long-term (10 yr) average (87,859 tonnes per annum)69. Land-won aggregate sand and gravel extraction is undertaken within two sites in the AONB at Shorwell and Knighton. While the impact of this scale of extraction is a concern in the short term, it is hoped in the longer term the landscape will be restored to a suitable quality following the closure of the extraction site. Marine aggregate used on the Island is mainly won from the English Channel. In terms of tonnage the three-year average (2018-21) of marine aggregates is 84,773 tonnes.
Aggregate recycling amounts to 180,000 tonnes per annum, with two sites within the AONB at Duxmore and Knighton.
The Isle of Wight has a duty to provide a proportion of land won mineral and as a result the AONB plays an important role in helping to deliver against housing demand / supply – the major use of aggregate here. As minerals can only be found at certain locations and these are largely found within the AONB, there is a disproportionate impact on the AONB from mineral extraction. In looking to the future, mineral extraction sites can be a force for good, providing rich bio-diverse sites, therefore the National Landscape Partnership need to be fully engaged in emerging minerals extraction proposals.
Soils
Soil is often overlooked as a vital resource. As well as being the largest terrestrial source of carbon, soils can store water to reduce flooding; can filter water to provide a clean potable resource; provide as habitat for a wide range of soil organisms that provide aeration and nutrient cycling and can provide a mineral rich medium for crop and tree growth. These functions are dependent on good soil structure which promotes root growth. Soils on calcareous substrates tend to be thinner than those in river valleys where the high component of peat provide an important carbon store. Sites at Alverstone have some of the deepest peat deposits in southern England and are an important reservoir of palaebotanical evidence of the post-glacial vegetation on the Isle of Wight70
Much of the Isle of Wight has good soils for agriculture, albeit no grade 1 Agricultural land. Good agricultural practices, as promoted through Isle of Wight Catchment Sensitive Farming initiative, will play an increasing role in improving soil management for good soil health.
The heavier soils on the Wealden clay areas are less prone to loss through both wind and water erosion; however, their pastoral nature means that damage from livestock may occur. Soils associated with the Lower Greensands produce some of the best arable land; however, the lighter nature of the soil does make it vulnerable to wind and water erosion.
Management Influences and Forces for Change
Island Plan Core Strategy
The Island Plan Core Strategy71 sets out the mineral’s strategy for the Island until 2027. In a separate guide72 the Isle of Wight Council sets out Mineral Safeguarding Areas to illustrate the land where may then prevent the extraction of minerals in the future. The guide explains which areas may be exempt from consideration in protecting mineral resources.
Catchment Sensitive Farming
Isle of Wight Catchment Sensitive Farming programme provides advice to farmers and land managers on how to reduce diffuse water pollution from agriculture, across priority catchments. This is a partnership project involving, Island Rivers (Catchment Partnership), Natural England, Environment Agency, Wight Rural Hub, Country Land and Business Association and National Farmers Union.
Water Framework Directive
Water pollution from erosion and soil run off impacts on Water Framework Directive objectives within the water bodies (see Chapter 10 for information on the WFD).
Nitrate Vulnerable Zone
A large percentage of Isle of Wight AONB is designated as a Nitrate Vulnerable Zone (NVZ) under the Nitrates Directive 1991. The Directive aims to reduce nitrate water pollution from agriculture and prevent such pollution occurring in the future. The NVZs cover most of the Chalk and Lower Greensand areas. Once a water body has been identified as nitrate sensitive, farmers must adopt a programme of measures which includes restricting how nutrients are applied to the land73.
Policies for Minerals and Soils
These policies should be read in conjunction with the overarching objectives for the Isle of Wight AONB as detailed on the welcome and overview page – Isle of Wight National Landscape: Area of Outstanding Natural Beauty Management Plan 2025-2030 – Isle of Wight National Landscape.
P19 Ensure that Isle of Wight AONB objectives are included in strategic plans and policies relating to mineral extraction both onshore and offshore (where it may impact upon a Heritage Coast).
P20 Ensure proposals for mineral extraction, in both active extraction and restoration phases, fully consider the impacts on the landscape of the Isle of Wight AONB and Heritage Coast and seek contributions to deliver mitigation and the enhancement to the features that form the special character of the Isle of Wight AONB where development is considered harmful.
P21 Encourage policies and programmes that encourage sustainable soil management and catchment sensitive farming.
Priorities for Delivery
- Encourage partners, industry, regulating bodies and landowners to work to ensure AONB objectives are embedded in minerals extraction proposals and restoration plans.
- Monitor, record, and celebrate the industrial archaeology and cultural heritage of mineral workings and develop resources and educational materials relating to vernacular architecture and mineral extraction from local geology.
- Encourage sustainable soil management practices, that conserve and enhance carbon and water storage capacity, through advice and guidance to all farmers and landowners in the Isle of Wight AONB with partners and regulators.