scholarly journals Small Area Estimation of Postfire Tree Density Using Continuous Forest Inventory Data

2021 ◽  
Vol 4 ◽  
Author(s):  
George C. Gaines ◽  
David L. R. Affleck
Keyword(s):  
Forest Inventory ◽  
Mean Squared Error ◽  
Tree Density ◽  
Standard Errors ◽  
Sample Sizes ◽  
Management Planning ◽  
Forest Management Planning ◽  
Continuous Forest ◽  
Sample Data ◽  
Regional Forest

Wildfire activity in the western United States is expanding and many western forests are struggling to regenerate postfire. Accurate estimates of forest regeneration following wildfire are critical for postfire forest management planning and monitoring forest dynamics. National or regional forest inventory programs can provide vegetation data for direct spatiotemporal domain estimation of postfire tree density, but samples within domains of administrative utility may be small (or empty). Indirect domain expansion estimators, which borrow extra-domain sample data to increase precision of domain estimates, offer a possible alternative. This research evaluates domain sample sizes and direct estimates in domains spanning large geographic extents and ranging from 1 to 10 years in temporal scope. In aggregate, domain sample sizes prove too small and standard errors of direct estimates too high. We subsequently compare two indirect estimators—one generated by averaging over observations that are proximate in space, the other by averaging over observations that are proximate in time—on the basis of estimated standard error. We also present a new estimator of the mean squared error (MSE) of indirect domain estimators which accounts for covariance between direct and indirect domain estimates. Borrowing sample data from within the geographic extents of our domains, but from an expanded set of measurement years, proves to be the superior strategy for augmenting domain sample sizes to reduce domain standard errors in this application. However, MSE estimates prove too frequently negative and highly variable for operational utility in this context, even when averaged over multiple proximate domains.

scholarly journals Timber Volume Estimation Model for Merchantable Tree Species in Sarmi Regency, Papua

Jurnal Wasian ◽  
2016 ◽  
Vol 3 (2) ◽  
pp. 91
Author(s):  
Relawan Kuswandi
Keyword(s):  
Forest Management ◽  
Forest Inventory ◽  
Standing Stock ◽  
Volume Estimation ◽  
Coefficient Of Determination ◽  
Estimation Model ◽  
Timber Volume ◽  
Management Planning ◽  
Forest Management Planning ◽  
Validation Test

Precise forest inventory to estimate standing stock is needed in forest management planning.  Therefore, it is necessary to have proper and reliable tools in estimating merchantable timber volume. This research was intended to build an accurate model to estimate timber volume for  merchantable species in logging concession of PT Wapoga Mutiara Timber, Sarmi Regency.  Regression equation between diameter and length did not have a significant correlation (coefficient of determination, R2 = 6.7 %). The best equation to estimate table tree volume based on validation test in logging concession of PT Wapoga Mutiara Timber was Log V = - 3.34 + 2.16 log d.     

scholarly journals Sawtimber Yield Tables for Pennsylvania Forest Management Planning

2010 ◽  
Vol 27 (4) ◽  
pp. 140-150
Author(s):  
Horacio Gilabert ◽  
Phillip J. Manning ◽  
Marc E. McDill ◽  
Steve Sterner
Keyword(s):  
Forest Management ◽  
Forest Type ◽  
Site Class ◽  
Management Planning ◽  
Forest Management Planning ◽  
Ecological Regions ◽  
Continuous Forest ◽  
Planning Project ◽  
Species Groups ◽  
The 1960S

Abstract Models to predict gross and net sawtimber volume per acre for even-aged stands were calibrated for Pennsylvania forests as part of a continuing forest management planning project for Pennsylvania's 2.1 million acres of state forestland. Because of the requirements of the models and limitations of the planning data, the main variable driving the yield models was age. Binary variables were used to shift the sawtimber volume predictions up or down to differentiate yields for 3 site classes, 2 stocking classes, 7 forest types, and 10 ecological regions within the state. The models were fitted using plot-level observations from a continuous forest inventory that has been carried out by the Pennsylvania Department of Conservation and Natural Resources Bureau of Forestry since the 1960s. To apportion the total volume into species groups, proportions were derived of the total sawtimber volume per acre for seven different species groups by forest type and site class for four macro-regions aggregated from the ecological regions within Pennsylvania.

Post-stratified estimation: within-strata and total sample size recommendations

2011 ◽  
Vol 41 (5) ◽  
pp. 1130-1139 ◽  
Author(s):  
James A. Westfall ◽  
Paul L. Patterson ◽  
John W. Coulston
Keyword(s):  
Sample Size ◽  
Forest Inventory ◽  
Total Sample ◽  
Standard Errors ◽  
Sample Sizes ◽  
Total Sample Size ◽  
Survey Statistics ◽  
Population Structures ◽  
The Mean ◽  
Volume Estimates

Post-stratification is used to reduce the variance of estimates of the mean. Because the stratification is not fixed in advance, within-strata sample sizes can be quite small. The survey statistics literature provides some guidance on minimum within-strata sample sizes; however, the recommendations and justifications are inconsistent and apply broadly for many different population structures. The impacts of minimum within-strata and total sample sizes on estimates of means and standard errors were examined for two forest inventory variables: proportion forestland and cubic net volume. Estimates of the means seem unbiased across a range of minimum within-strata sample sizes. A ratio that described the decrease in variability with increasing sample size allowed for assessment of minimum within-strata sample requirements to obtain stable estimates of means. This metric indicated that the minimum within-strata sample size should be at least 10. Estimates of standard errors were found to be biased at small total sample sizes. To obtain a bias of less than 3%, the required minimum total sample size was 25 for proportion forestland and 75 for cubic net volume. The results presented allow analysts to determine within-stratum and total sample size requirements corresponding to their criteria for acceptable levels of bias and variability.

scholarly journals On the concept of modern forest management in Russia

2017 ◽  
Author(s):  
Н.А. Моисеев
Keyword(s):  
Forest Management ◽  
Strategic Planning ◽  
Russian Federation ◽  
Forest Inventory ◽  
Sustainable Forest Management ◽  
Federal Law ◽  
Management Planning ◽  
Forest Management Planning ◽  
The Russian Federation ◽  
The Government

В статье рассматриваются основные положения лесоустройства с учетом истории его развития в России и в отдельных странах мира, в том числе в Германии, где оно первоначально зародилось. Особое внимание уделяется его функциональному назначению, содержанию, методологии стратегического планирования в рамках лесоустройства и его связи с принятым в 2014 г. Правительством РФ Федеральным законом № 172 «О стратегическом планировании в Российской Федерации». Известно, что последним Лесным кодексом РФ (2006) лесоустройство было упразднено, что негативно отразилось не только на лесоуправлении, но и на состоянии лесного сектора экономики. При этом были искажены и основные понятия, утвердившиеся ранее в лесной науке и практике. В связи с изложенным, в статье последовательно рассматриваются: вначале ключевые понятия, лежащие в основе лесоуправления и специфика его, предопределяющая истоки возникновения лесоустройства; двухуровневый характер стратегического лесоустроительного планирования; его методология; другие функции лесоустройства, включая учет лесов, оценку прошлого хозяйства; организацию и расчет непрерывного неистощительного пользования лесом (ННПЛ); экономическое обоснование лесных программ, формирующихся при лесоустройстве на уровнях субъекта РФ и входящих в него лесничеств; механизм их реализации; рекомендации по совершенствованию лесоуправления и контроль за ним. Изложенные концептуальные положения могут быть использованы при разработке новой лесоустроительной инструкции. The article examines the main provisions of forest management consider the history of its development in Russia and in certain countries, including Germany, where it originally arise. Particular attention is paid to its functional purpose, content, methodology of strategic planning within the forest inventory and its relationship with the Federal Law No. 172 «On Strategic Planning in the Russian Federation» adopted in 2014 by the Government of the Russian Federation. It is known that by the last «Forest code of the Russian Federation» (2006) the forest inventory was abolished, which negatively affected not only on the forest management, but also on the state of the forestry sector of the economy. Herewith was distorted and the basic concepts established earlier in forest science and practice. In connection with the foregoing, the article consistently examines: first, the key concepts underlying the forest management and its specificity predetermining the cradle of forest management; two-level nature of strategic forest management planning; Its methodology; other functions of forest management, including forest inventory, assessment of the past forestry; organization and calculation of continuous sustainable forest management (NNPL); the economic substantiation of forest programs formed during forest management at the levels of the subject of the Russian Federation and constituent in it forestries; mechanism for their implementation; recommendations for the improvement of forest management and control over it. The outlined conceptual statements could be used in the development of a new forest management instruction.

On the error of estimates from successive forest inventories with SPR

1987 ◽  
Vol 17 (5) ◽  
pp. 442-447
Author(s):  
Tiberius Cunia
Keyword(s):  
Forest Inventory ◽  
Random Sampling ◽  
Regression Coefficients ◽  
Partial Replacement ◽  
Forest Inventories ◽  
Continuous Forest ◽  
Regression Functions ◽  
The Given ◽  
Linear Regressions ◽  
Continuous Forest Inventory

The approach used by Cunia to combine the error from sample plots with the error from volume or biomass tables when Continuous Forest Inventory (CFI) estimates of current values and growth are calculated is extended to the CFI systems using Sampling with Partial Replacement (SPR). The formulae are derived for the case of SPR on two measurement occasions when (i) volume or biomass tables are constructed from linear regressions for which an estimate of the covariance matrix of the regression coefficients is known, and (ii) the sample plots or points are selected by random sampling independently of the given volume or biomass regression functions.

Developing and Implementing Multiple-Use Forest Management Planning in Turkey

2008 ◽  
Vol 42 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Emin Zeki Baskent ◽  
Salih Terzioğlu ◽  
Şağdan Başkaya
Keyword(s):  
Forest Management ◽  
Multiple Use ◽  
Management Planning ◽  
Forest Management Planning

scholarly journals Opportunities for the application of linear program­ming in forest management planning

2013 ◽  
pp. 175-191
Author(s):  
Damjan Pantic ◽  
Bojan Tubic ◽  
Marko Marinkovic ◽  
Dragan Borota ◽  
Snezana Obradovic
Keyword(s):  
Linear Programming ◽  
Maximum Yield ◽  
Half Period ◽  
Management Planning ◽  
Forest Management Planning ◽  
Conflicting Interests ◽  
Poplar Plantations ◽  
The One ◽  
Forest Practice ◽  
The U.S

In situations where it is necessary to consider a variety of options when making decisions in forestry (and in general), with the choice influenced by hardly comparable criteria and a number of conflicting interests, a possible solution is to use multiple criteria methods. One of these methods, which can be applied in forestry, is mathematical programming (in particular, linear programming). Linear programming has a long tradition of being used in the U.S. and European forestry, whereas in the forestry of Serbia it still represents a theoretically and practically unknown tool. Therefore, in this paper we analyze the possibility of applying the methods of linear programming in developing a plan of regeneration cutting in the poplar plantations of FMU "Topolik" managed by PE "Vojvodinasume." Using the aimed function (linear programming) and the corresponding software package the maximum yield that can be achieved by cutting the plantation was obtained. The planned management period was from 2012 to 2021 and its volume was 155 852 m3. The preset condition that the yield in half-periods remains equal was fulfilled (half-period I 77,925 m3, half-period II 77,927 m3). The maximum yield obtained with this methodology was by 4,040 m3 lower than the theoretically possible yield that would be obtained if all stands were cut down at the end of the second half-period, i.e. higher by 8,430 m3 than the yield that would be obtained if cutting of the stands were performed at the start of the management period. The results obtained and foreign experience in this area clearly indicate that linear programming can successfully be used to solve this problem and even more complex problems (than the one presented in this paper) in our local forest practice (multidimensional planning with a series of constraints).

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