Details

Autor(en) / Beteiligte

• Blaschke, Paul M.
• Trustrum, Noel A.
• DeRose, Ron C.

Titel

Ecosystem processes and sustainable land use in New Zealand steeplands

Ist Teil von

• Agriculture, ecosystems & environment, 1992, Vol.41 (2), p.153-178

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

1992

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• Lowland steeplands cover more than 40% of New Zealand's area. Occurring in a tectonically active environment and subject to recurrent erosion-inducing storms, they were largely forest-covered until about 130 years ago, when they were rapidly deforested and converted to pastoral land use. We describe the geographical and historical background to this deforestation and some of the profound ecosystem process changes that have accompanied it, particularly those related to mass movement erosion. We then relate research findings on the ecosystem changes to the sustainability of current land use. Our own research in three contrasting regions of the North Island, New Zealand has examined disturbance regimes, vegetation succession, soil properties and soil erosion rates on pastoral hillslopes and in forest ecosystems. Under both forest and pasture, almost all ecosystem processes were highly dependent on topographical unit and slope steepness. A comparison of ecological process and erosion rates in pasture and forest, and analysis of pastoral production data, indicated that although significant erosion occurred under forest and was one of its principal regeneration mechanisms, rapid net soil depletion was occurring on steep hillslopes under pasture and that pastoral use was not sustainable on these areas. A more sustainable pattern of land use can be achieved by intensification of pastoral use on gentler hillslopes and better spatial integration of pastoral use with timber plantation, agroforestry, and conservation land uses. Strategies for the implementation of more sustainable land management are also discussed. Establishment of critical parameters for the development of land management guidelines has been dependent on a good prior understanding of landscape ecological processes.