Soil carbon and the New Zealand Agricultural Greenhouse Gas Research Centre

摘要

The New Zealand Agricultural Greenhouse Gas Research Centre was recently established. One of three core science areas will develop management guidelines for the conservation and, where likely, sustainable increase of soil carbon (C) storage associatedwith land-based food and fibre producing activities. It has been estimated that soils beneath grazed pasture store 85% of New Zealand's soil C to a depth of 0.3 m. Research has improved estimation at a national scale, but pastoral soils data remains fragmented, geographic coverage limited, and most samples obtained from a depth < 0.1 m. There has been little research about manipulating and verifying C storage rate in soils beneath grazed pasture. For these soils, C storage is already substantial including some from primal forest vegetation cleared by European settlers around 150 years ago. Modelling will develop better understanding of influential soil C cycling processes in grazed pasture systems. A potential for soil C storage will be estimated as well as the proportion that has been realised. Measuring and verifying the likely slow, relatively small and variable changes in soil C storage will be difficult. Connecting models and field measurements, accounting 'rules' are envisaged, guiding soil C storage management on New Zealand's farms.