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Estimation of forest canopy cover: A comparison of field measurement techniques


, : Estimation of forest canopy cover: A comparison of field measurement techniques. Silva Fennica 40(4): 577-588

Estimation of forest canopy cover has recently been included in many forest inventory programmes. In this study, after discussing how canopy cover is defined, different ground-based canopy cover estimation techniques are compared to determine which would be the most feasible for a large scale forest inventory. Canopy cover was estimated in 19 Scots pine or Norway spruce dominated plots using the Cajanus tube, line intersect sampling, modified spherical densiometer, digital photographs, and ocular estimation. The comparisons were based on the differences in values acquired with selected techniques and control values acquired with the Cajanus tube. The statistical significance of the differences between the techniques was tested with the nonparametric Kmskall-Wallis analysis of variance and multiple comparisons. The results indicate that different techniques yield considerably different canopy cover estimates. In general, labour intensive techniques (the Cajanus tube, line intersect sampling) provide unbiased and more precise estimates, whereas the estimates provided by fast techniques (digital photographs, ocular estimation) have larger variances and may also be seriously biased.

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Führmann, T.; Ghosh, M.; Otero, A.; Goss, B.; Dargaville, T.R.; Pearse, D.D.; Dalton, P.D., 2015: Peptide-functionalized polymeric nanoparticles for active targeting of damaged tissue in animals with experimental autoimmune encephalomyelitis. Increased permeability of blood vessels is an indicator for various injuries and diseases, including multiple sclerosis (MS), of the central nervous system. Nanoparticles have the potential to deliver drugs locally to sites of tissue damage, reduc...

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Odegard O.; Unsgard G., 1977: Fracture of the femoral neck a socio medical problem. Acta Orthopaedica Scandinavica 48(2): 228

Weinstein, L.; Alscher-Herman, R., 1981: Physiological responses of plants to fluorine Pollutant, plant damage. Proceedings Easter School in Agricultural Science University of Nottingham: 1) 139-167

Botello-Harbaum, M.; Haynie, D.L.; Murray, K.W.; Iannotti, R.J., 2011: Cigarette smoking status and recurrent subjective health complaints among US school-aged adolescents. Subjective health complaints are common among adolescents. There is evidence that girls are more likely to register complaints than boys. This study examines gender differences in the relationship between daily smoking and recurrent subjective hea...

Lteif, G.N.; Mavissakalian, M.R., 1995: Life events and panic disorder/agoraphobia. A patient-rated checklist adapted from the Psychiatric Epidemiology Research Interview was used to assess frequency and desirability of life events in the 12 months preceding an index evaluation of a large sample of patients with a DSM-III diagnos...

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Allen, AA., 1979: Longitarsus rutilus (Ill.) (Col., Chrysomelidae) in east Cornwall. Entomologist's Monthly Magazine, 114(Jan.-Apr.): 62 .