Implementing point-poisson and point-model based sampling in forest inventory

Wood, G. B.; Schreuder, Hans T.

doi:10.1016/0378-1127(86)90099-x

Cited by 8 publications

(8 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Stratification should be carried out at the time of measurement to ensure that a reasonable sample is obtained in each class (Wood & Schreuder (1986) recommend at least 20 trees). Effect of plot type With the exception of the POTS inventories (discussed later), the estimates of particleboard volume removed and total volume removed derived from FA samples and VR samples were within 1 m 3 ha-• (10Jo) of each other and approximately 5m 3 ha-• (6%) below the actual removals (Table 1).…”

Section: Resultsmentioning

confidence: 99%

“…The basic specifications for sawlogs were: minimum small-end diameter 20 em under bark, minimum length 2.1 m (3.0 m preferred), and for particleboard logs were: minimum small end diameter 10 em under bark, minimum length 5.4 m. Limits were also placed on the amount of sweep, knots etc. The model-based Telerelaskop inventories (MBT/FA & MBT/VR) were conducted using the methods described by Wood and Schreuder (1986). A Telerelaskop (Bitterlich 1978) was used to measure all second stage sample trees whether marked for thinning or not and the product grade of each measured log was assessed visually.…”

Section: The Study Sitementioning

confidence: 99%

“…Wood and Schreuder (1986) recommended that the ratio of the number of sample plots to the number of sample trees should be between one and two, with values close to one when the main interest is in the assortment of products. A sample of 29 trees was selected for each of the MB inventories, giving a value of the ratio of sample plots to sample trees of 1.3.…”

Section: B) Second Stage Samplesmentioning

confidence: 99%

See 2 more Smart Citations

Comparison of four inventory designs for estimating yields from the thinning of pine plantations

Biggs¹

1990

Australian Forestry

View full text Add to dashboard Cite

Four inventory designs were used to predict the yields of commercial products from a second thinning of a 21-year-old Pinus radiata plantation: (I) standard, single stage inventory with visual assessment of products and volumes derived from taper tables; (2) model based inventory with visual assessment of products and volumes measured by Telerelaskop; (3) model based inventory with visual assessment of products and volumes measured by Spiegel Relaskop; (4) single stage inventory with computer modelling of both thinning and utilisation and volumes derived from taper tables. Both fixed area and variable radius (point sample) plots were tested with each design.Most accurate results were achieved with designs I and 2 but the model based inventory was quicker and cheaper to implement because assessment of products was confined to a small sub-sample of trees. The Spiegel Relaskop underestimated volumes in the small diameter classes, whilst the modelling inventory gave the least accurate estimates due mainly to errors in the thinning model. Inventories using fixed-area plots were more accurate than those based on variable-radius plots but equally precise (i.e. had the same sampling errors). As more trees were measured on the fixed-area plots, they were less efficient than variable-radius plots.Model-based sampling may be the most suitable method for estimating the yields of products from thinning of pine plantations.Simulation of thinning operations using computer modelling systems such as Pars may be preferred where different management options are to be evaluated but the accuracy of the models must be monitored against field practice.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: The Study Sitementioning

confidence: 99%

Section: B) Second Stage Samplesmentioning

confidence: 99%

See 1 more Smart Citation

Comparison of four inventory designs for estimating yields from the thinning of pine plantations

Biggs¹

1990

Australian Forestry

View full text Add to dashboard Cite

show abstract

“…Point-3P applied mainly in North America (Rennie, 1976;Rennie et al, 1991;West, 2011) and research studies have been conducted in Chile-South America (Harris-Pascal, 2015), in Canada (Williams & Wiant, 1998), in Australia (Wood & Schreuder, 1986;Wood & Wiant Jr., 1992), in New…”

Section: The Point-3p Sampling Methodsmentioning

confidence: 99%

“…(Wood & Wiant Jr., 1992), Miombo savanna woodlands (Osman & Idris, 2012) and plantations of hardwood (Harris-Pascal, 2015) and softwood (Lee & Goulding, 2002) trees. The vast majority of Point-3P applications refer to timber volume estimations (Gregoire & Valentine, 2007a;Harris-Pascal, 2015;Rennie et al, 1991;Stamatellos, 1995;West, 2011;Williams & Wiant, 1998;Wood & Schreuder, 1986) and merchantable log products for timber sales (saw-log, pulp-millable wood volume) (Lee & Goulding, 2002;Osman & Idris, 2012;Rennie, 1976;Schreuder, Ouyang, & Williams, 1992;Wood & Wiant Jr., 1992). Apart from volume estimation, Point-3P sampling can be implemented for any stand attribute estimations (Kershaw Jr. et al, 2016b).…”

Section: The Point-3p Sampling Methodsmentioning

confidence: 99%

Two Contemporary and Efficient Two-Stage Sampling Methods for Estimating the Volume of Forest Stands: A Brief Overview and Unified Mathematical Description

Georgakis¹,

Stamatellos²

2019

OJF

View full text Add to dashboard Cite

Big Basal Area Factor (Big BAF) and Point-3P are two-stage sampling methods. In the first stage the sampling units, in both methods, are Bitterlich points where the selection of the trees is proportional to their basal area. In the second stage, sampling units are trees which are a subset of the first stage trees. In the Big BAF method, the probability of selecting trees in the second stage is made proportional to the two BAFs' ratio, with a basal area factor larger than that of the first stage. In the Point-3P method the probability of selecting trees, in the second stage, is based on the height prediction and use of a specific random number table. Estimates of the forest stands' volume and their sampling errors are based on the theory of the product of two random variables. The increasing error in the second stage is small, but the total cost of measuring the trees is much smaller than simply using the first stage, with all the trees measured. In general, the two sampling methods are modern and cost-effective approaches that can be applied in forest stand inventories for forest management purposes and are receiving the growing interest of researchers in the current decade.

show abstract

Test of application of centroid and importance sampling in a point-3P forest inventory

Wood

Wiant

1992

Forest Ecology and Management

View full text Add to dashboard Cite

Implementing point-poisson and point-model based sampling in forest inventory

Cited by 8 publications

References 4 publications

Comparison of four inventory designs for estimating yields from the thinning of pine plantations

Comparison of four inventory designs for estimating yields from the thinning of pine plantations

Two Contemporary and Efficient Two-Stage Sampling Methods for Estimating the Volume of Forest Stands: A Brief Overview and Unified Mathematical Description

Test of application of centroid and importance sampling in a point-3P forest inventory

Contact Info

Product

Resources

About