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Accuracy of tree height estimation based on LIDAR data analysis

100%

Sterenczak K., Zasada M.

Folia Forestalia Polonica. Series A . Forestry

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2011

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tom 53

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nr 2

Some modern remote sensing technologies, including LIDAR (LIght Detection And Ranging), have significantly developed recently. Laser scanners mounted on the airborne platform make it possible to collect very precise information over large areas, including tree and stand heights. A literature review shows that the model-based method of tree height determination underestimates this parameter in comparison to field measurements. The objective of the study was to analyze accuracy of the automatic height estimation of Scots pine stands, based on the airborne laser scanning data and the example of the Milicz Forest District. Applied algorithm of the stand segmentation into individual trees gave systematic and significant underestimation of the number of trees. The minimum tree height was estimated with a large negative error reaching up to several meters. The maximum mean and top heights were determined more precisely, with a small negative error of a few percent. The sum of tree heights was determined with an error exceeding 40%, which is caused mostly by the error in estimation of the number of trees.

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Estimates and forecasts of forest biomass and carbon sequestration in North America and Australia: a forty-five year quest

84%

Botkin D. B., Ngugi M. R., Doley D.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2014

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tom 57

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nr 192

A half-century of forest inventory research involving statistically-valid fieldmeasurements (using statistically representative sample size and showing confidence limits) and well-validated forecasting methods are reviewed in this paper. Some current procedures overestimate global and large-scale forest biomass, carbonstorage, and carbon sequestering rates because they are based on statistically-invalid methods (errors in estimates are unavailable and unreported), or they fail to consider key dynamic characteristics of forests. It is sometimes assumed that old-growth forests can serve as fixed, steady-state storage of biomass and carbon for indefinitely long periods, but it is shown by both modelling and remote sensing that forests are dynamic systems, the state of which can change considerably over as shorta time as a decade. Forecasting methods show that maximum biomass and carbon storage in some important forest types occurs in mid-succession, not in old-growth. It is proposed, therefore, that realistic biomass and carbon storage estimates used for carbon credits and offsets be determined as the statistical mean minus the confidence interval and that practical carbon sequestering programs include specific timeframes, not indefinitely long periods of time.

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A taper model for Norway spruce (Picea abies (L.) Karst.)

84%

Socha J.

Electronic Journal of Polish Agricultural Universities. Series: Forestry

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2002

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tom 05

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nr 2

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Estimating forest biomass by remote sensing RADAR data in Brazil

84%

Santos J. R., Gama F. F., da Conceicao Bispo P.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2014

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tom 57

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nr 192

Ograniczanie wyników

2 Drewno. Prace Naukowe. Doniesienia. Komunikaty

1 Electronic Journal of Polish Agricultural Universities. Series: Forestry

1 Folia Forestalia Polonica. Series A . Forestry

1 Botkin D. B.

1 Doley D.

1 Gama F. F.

1 Ngugi M. R.

1 Santos J. R.

1 Socha J.

1 Sterenczak K.

1 Zasada M.

1 da Conceicao Bispo P.

2 2014

1 2011

1 2002

Accuracy of tree height estimation based on LIDAR data analysis

Estimates and forecasts of forest biomass and carbon sequestration in North America and Australia: a forty-five year quest

A taper model for Norway spruce (Picea abies (L.) Karst.)

Estimating forest biomass by remote sensing RADAR data in Brazil