Forest Research: Open Access
Open Access

Institute Fysieke Veiligheid, Arnhem, Netherlands

Biography

Ester Willemsen is affiliated to Institute Fysieke Veiligheid, Arnhem, Netherlands. Ester Willemsen is a recipient of many awards and grants for her valuable contributions and discoveries in major area of subject research. Ester Willemsen research interests reflect in her wide range of publications in various national and international journals

Publications

• Research   
  Comparing Canopy Metric Estimations Using Three Conifer Species in the Netherlands
  Author(s): Alan Duncan Hibler, Brian P. Oswald*, Nienke Brouwer, Ester Willemsen and Hans M. Williams
  
  A growing concern associated with fire in The Netherlands is estimating the spread of wildfire, however often the data needed to estimate canopy fires are lacking. The primary parameter required is canopy bulk density (CBD), which requires estimations of canopy gap fraction and leaf area index (LAI). The accuracy of three indirect methods of estimating CBD (a densiometer, hemispherical canopy photographs (HCP), and a LI-COR LAI 2200c plant canopy analyzer) was compared for three common tree species in the Netherlands [Scots pine (Pinus sylvestris L.), black pine (Pinus nigra Arnold) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)]. No differences between species were found for CBD, but the denser canopies in the Douglas-fir stands did have significantly lower gap fractions than the two pine species. The HCP method produced higher gap fraction estimates than the other two method.. View More»
  DOI: 10. 35248/2168-9776.20.9.238

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