Soils

Soils are fundamental to Marlborough's economic, environmental and social wellbeing. We use soils to grow our fruit, vegetables, crops and timber and raise animals.

See a map of soil types in Marlborough

What is soil?

Soil is the top layer of material on the surface of the earth that plants grow in. Soil is made of a combination of different elements including minerals, rock fragments, dead and decaying organic matter and living organisms. Soil forms in soil horizons (layers) that extend (sometimes metres) down to an underlying-mineral rock layer. Soils form in parent material which may have formed from the underlying rock or has been transported there by wind, ice or water. Soils evolve over time through the additions and losses of materials. Such changes can be influenced by climate, living organisms, topography and original parent materials. Soils are therefore highly variable in their composition, attributes and appearance.

Why is soil important?

Soils are fundamental to a range of ecosystem functions. Our soils are vital for the storage of water and nutrients; they mitigate greenhouse gas emissions, and act as a buffer between the atmosphere and aquatic environments.

We also depend on soil to treat and contain many of the contaminants we deliberately or inadvertently release into the environment.

Marlborough’s social and economic development has historically been based on its strong primary production sector, including farming, forestry, food (and supplementary feed) crops, horticulture and most recently, viticulture. The ability to grow pasture and a wide variety of crops relies upon the health of our soil resources. In fulfilling these functions, soil

helps to maintain community health standards and protect water resources from contamination. Soil also acts to absorb, channel and store water, a particularly important function in Marlborough’s dry climate.

Soils are at the heart of our environment and economy, underpinning our agriculture, viticulture, and forestry industries and complementing our clean green tourism image. Soils are the living mantle of our earth.

Different types of soil

Like the rest of New Zealand, Marlborough has a diverse range of soils. In fact, there are over 87 different soil types in Marlborough. These represent eight of the 15 soil orders described by the New Zealand Soil Classification.

The large number of soil types within Marlborough reflects the variation of parent materials, length of soil development, vegetation, the climate (ie; mean annual rainfall and presence or absence of drought) and topography.

These range of soils have different properties or characteristics. These characteristics mean that some soils will be more suitable for certain land uses than others. For example, some areas have soils and a climate particularly suited to growing pasture while others are more suited to growing fruit trees.

How do our actions affect soil?

Human activity can alter the character and quality of our soils. Pollution from industry can cause long-term soil contamination. Farming can maintain and improve soil quality but some intensive farming practices can have negative effects such as increased soil erosion or soil compaction. The recontouring of land to better accommodate viticulture or irrigation systems has become common place and can result in serious disturbance to soils. Consequently, more soils are being mapped as anthropic (human-influenced) soils in Marlborough.