The effects of changing resource use in the Marlborough Sounds
Degree GrantorUniversity of Canterbury
Degree NameMaster of Science
The Marlborough Sounds is an area of New Zealand that possesses great scenic beauty. The area is biculturally and ecologically significant, a recreational haven and is a great resource both economically, historically and environmentally. The physical appearance of Marlborough has radically changed over the last two centuries due to human occupation and development of water resources (such as transportation, recreation, and mussel and fish farming) and land resources (such as forestry, conservation and residential development). Development in the Sounds has been occurring due to increased demand for resources both on land and in water, forming a collage of different land and water uses. Some activities in the Marlborough Sounds are having a detrimental effect on the environment due to unsustainable development. This thesis examines some contemporary issues relating to the environmental effects that land and water uses are having on the Marlborough Sounds Area. The topic is examined through two main themes, forestry and fast ferries and their effect on the coastal zone.
Productive land uses in the Sounds are limited due to the steep sloped topography and low fertility soils. Exotic forestry plantation is one of the few land uses that can excel in such conditions. Development in the area has moved from farming to forestry as wool and meat prices declined and as soil fertility decreased with burning as a form of weed control. However, there have been problems in the conversion to forestry. Wilding pines are penetrating the regenerated native forest that does remain. This forest type is unique as it is the southern-most point for many native species. Another effect of forestry in the sounds is its influence on the coastal zone through sedimentation. Mass siltation causes bay infilling or suspended sediment levels to increase. This occurs at greatest rates when clearing the land to plant or when logging. This has effects on other land and water uses, such as marine farming and recreation (as the aesthetics of the hillside during logging are decreased).
Development of the Marlborough Sounds has also occurred on water. From the time Tory Channel was discovered, it has been heavily utilised. First by Maori canoes, then early whalers, cargo ships, cruiseliners and since 1962 ferry traffic between Wellington and Picton. The vital transport networks and infrastructure have aided in the development of the region. This has led to an increase in large boat traffic in the Marlborough Sounds resulting in different wave energies working the shoreline. The second theme of this thesis discusses the recent introduction of the 'fast ferries' and how they have caused the remodelling of beach morphologies in the ferry corridor. The change to various beaches and rock outcrops in the Sounds has been significant but it is difficult to interpret the cause of change as a number of factors influence the shoreline. People's perception of fast ferry damage is often different to fact. A variety of situations where alleged damage to the coastline and coastal structures are examined.