The land overlays are developed from amalgamated units from the land use capability (LUC) assessment of the New Zealand Land Resource Inventory (NZLRI) Gisborne East Coast Region, Second Edition, June 1999. In the NZLRI the maximum erosion severity has been assessed for each LUC unit and this is based on the geology, soil type, steepness, climate and vegetation cover. The land overlays comprise the following LUC units: Land Overlay 1 Classes I-IV and VIe1, 2, 3, 5, 7 and 8 inclusive, Land Overlay 2 Balance of Class VI, Land Overlay 3 (including 3A) Classes VII & VIII (see C7.1.5 for detailed units).
Erosion is the natural process of soil and rock wearing away and being moved through the landscape. Erosion includes sheet, wind, creep, slump, flow, rill, earthflow, gully, tunnel gully and stream erosion. In areas undisturbed by human activity, the rate of erosion is determined by geology and weather. Land uses, particularly those that reduce vegetation cover or disturb the soil can lead to a much faster rate of erosion. This is especially heightened in naturally unstable areas where even relatively minor landuse activities can have major impacts. Erosion that has been increased by human action is called induced or accelerated erosion and despite the voluntary erosion control efforts of many landowners and kaitiaki, this remains the major landuse issue in the district that also impacts on the district’s waterways and coastal seabed and key assets such as roading.
