Evaluating the utility of photogrammetry to identify and map regions at risk from gully erosion

[摘要] Soil erosion is one of three key indicators (carbon dynamics, acidification and soil erosion) of soil condition and currently exceeds soil formation rates by several orders of magnitude for much of Australia. This loss of valuable topsoil is a major risk to agricultural productivity and a major contributor of sediment and nutrient load to Australian stream and river systems. In particular, exported sediment and nutrients from Great Barrier Reef (GBR) catchments impact World Heritage coral reef ecosystems. Amongst a range of erosion processes, gully erosion causes significant land degradation and is a major contributor of sediment load to river systems. It can be the dominant erosion process in some regions. Ongoing monitoring of land use and cover is an important element in assessing erosion risk and requires a mixture of modelling, remote sensing and observations depending on the scale of the impact area assessed. More is needed to identify and monitor gully erosion, however.This study evaluates the suitability and application of digital photogrammetry applied to aerial images routinely collected by state land survey agencies to the challenges posed by gully erosion and sedimentation. Aerial photogrammetry can be used to produce high-resolution contoured surfaces and flow path prediction maps capable of identifying effectiveness of erosion management structures and changes in surface water flows. These flow path maps provide a relevant representation of the likely location of surface water movement in the landscape by capturing major stream paths and help to identify sites affected by concentrated surface flows that may contribute to stream bank erosion.

[发布日期] 2018-05-23 [发布机构] CSIRO

[学科分类] 地球科学(综合)