The area of the Marlborough district is some 17,517 square kilometres, of which the land resource covers 10,321 square kilometres. Marlborough's unique landscape, some of the most spectacular in New Zealand, of mountain ranges and river valleys were formed some 25 million years ago by the collision of the Pacific and Indo-Australian tectonic plates.
The Marlborough Sounds, formed as a result of this collision, have slowly been tilted towards the northwest causing the headwaters of the former Pelorus and Queen Charlotte Valleys to be submerged to create the distinctive ria (submerged river valley) coastline.
Each of Marlborough's major river valleys follows a major earthquake fault line. The Wairau Fault, the northeast extension of the main New Zealand Alpine Fault, divides Marlborough into two distinctive geographical regions, the Marlborough Sounds and the Wairau/Awatere area.
In the Wairau/Awatere area, the sea has also been a fundamental influence on the formation of the Wairau Plain. Some 14,000 years ago after the last glacial period the lower Wairau Plain was inundated by the sea, evidence of this being the sand dunes at Riverlands, and wave-cut spurs on the Wither Hills. At Rarangi this influence can be seen in rock stacks and wave-cut faces and in the series of raised beaches which have been built up by the boulder bank across Cloudy Bay some 6,000 years ago.
Successions of people have derived their sustenance from the Marlborough vegetation and wildlife over the last 1000 years. The great diversity of forests and wetlands and broad range of wildlife habitats made Marlborough an exceedingly rich environment with bountiful supplies of timber, flax, waterfowl, eels and forest birds. However the major habitat destruction caused by the 'Fires of Tamatea', which occurred throughout the eastern South Island, meant a huge loss of habitat and the extinction of many species.
The resulting creation of vast grasslands, ideal for pastoral farming, paved the way for the loss of Maori land to the Europeans. The Europeans continued the change to the environment by burning, grazing, introducing wild animals (both herbivores and carnivores), plants, clearing forest and shrubland, timber and flax milling, gold mining, drainage of wetlands, flood control, exotic forestry, urban development and the use of agrichemicals.
Marlborough today is a progressive and busy district with a range of active industries that provide wealth and employment for its people. The expanding tourism, marine farming and viticulture industries are now replacing traditional farming, forestry and fruit growing activities.
The rapid change in land use/crop type to vineyards in parts of Marlborough has resulted in large numbers of copper chromium arsenic (CCA) treated posts being used in the ground. The Marlborough District Council contracted Hort Research to investigate the environmental effects of these posts within the Wairau Plain area. The work was preliminary in nature and was designed to detect whether leaching of CCA chemicals from the posts to surrounding soils, and potentially groundwater was occurring.
The work has detected leaching in a range of soil types with the chemicals being detected at elevated levels around and below the posts, generally within 50 - 100mm. About 25% of the samples showed arsenic at levels above the agricultural soil health guidelines. Further work to assess the risk to shallow groundwater is being carried out.
Click HERE for the Hort Research CCA Report - Preliminary (196kb)
Click HERE for the Hort Research CAA Stage 2 Report - Final (1.5mb)
The Starborough Flaxbourne Soil Conservation Landcare Group Project 2005 - 2008 - Marlborough
The Starborough/
Flaxbourne Soil Conservation Project was established in mid 2005 to address a range of issues relating to the sustainable management of agricultural land in the Seddon/Ward areas of Marlborough, with particular reference to the challenges of the potential impacts of climate change. The project was funded for a three year period by the Sustainable Farming Fund and was concluded in June 2008.
The main concluding event was a national field day entitled "Beyond Reasonable Drought; adapting dryland farming to climate change" held on the Avery family farm "Bonavaree" at Grassmere on May 14th 2008. The field day aimed to integrate all of the information relevant to the project, including soils work, plant trials, climate change work and landscape and farm systems analysis. A series of brochures and a booklet summarising the research and conclusions of the project have been produced, setting out suggested best practice guidelines for landowners to consider.
At Bonavaree Farm, the first steps have taken towards an integrated and sustainable management scenario where lucerne provides nutritious stock fodder on the most productive areas, shrubs including saltbush and tagasaste hold soils on erosion-prone slopes, natural biodiversity areas are protected and blocks and belts of trees offer shelter, shade and eventually maybe an income from hardwood timber." With Photo - see below
Field Day - "Beyond Reasonable Drought" - May 2008
Click below for information on the Field Day which was held on 14 May 2008.
Click below for copies of field day brochures:
Starborough/Flaxbourne Soil Conservation Project - Report
Beyond Reasonable Drought - Adapting Dryland Farming to Climate Change - August 2008
