Is the application of remote sensing to weed mapping just 'S-pie in the sky'?
Dave BulmanA, School of Geography and Environmental Science, Monash University and Cooperative Research Centre for Weed Management Systems, Clayton, Victoria 3168, Australia.
A Current address: Army Engineering Agency, Support Command Australia (Army), Private Bag 12, PO Ascot Vale, Victoria 3032, Australia.
The play on words expressed in the title underlies a more significant question regarding the prospects for using remote sensing technology to map the extent of environmental weeds that seriously impact on agriculture: How realistic is the expectation that remote sensing can become routinely applied to weed mapping? This paper presents an overview of remote sensing and how it works, examines how it has been used for land and resource evaluation and monitoring, and describes briefly some of the inherent difficulties associated with its application to weed mapping using, as an example, research on mapping Paterson's curse, a weed of perennial pastures.
An explanation is given about some of the key factors relating to the spectral characteristics of the weed, and its behaviour in response to natural and human factors and shows that infested areas can be mapped but that determining weed distribution and density are not always possible using currently available remotely sensed data. In particular, it demonstrates that the use of high resolution data solves some of the difficulties encountered when lower resolution data are employed for weed mapping. In conclusion, it points to answering the above question with the proposition that: Much depends upon the characteristics, behaviour and environments of the weeds; and future developments in remote sensing technology.
Plant Protection Quarterly (2000) 15 (3) 127-131.