Forest Measurement and Modelling.
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Stripline sampling Forest Measurement and Modelling. |
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Striplines are a long rectangular plot, usually 5-40 m wide and up to several kilometers long. The distance between the strips depends on a number of factors including sampling intensity, topography, forest composition, and other factors. Strips are most convenient if information on topography and forest composition is also required as part of the survey and if dense undergrowth or difficult terrain necessitates spending a disproportionate amount of time on plot establishment. Conventionally, strips are run at right angles to the contours of the main topography of the area under survey because the fertility gradient usually runs in this direction. For a given sampling intensity, a stripline survey may be faster than a survey based on plots because the ratio of working time on the units to the travelling time between units is greater for strips. However, the number of units and therefore the number of degrees of freedom for calculating sampling error are often far fewer for strips than plots. Strips and plots may be combined in what are called Line Plots. With these, topographical and forest type data are gathered from the strips and quantitative information (diameter, height, volume, etc.) is obtained from plots located at intervals along the strips. |
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[strip.htm] Revision: 7/2000 |