Variance approximations were developed to estimate the variances of total basal area per acre and total volume per acre for both point and plot samples. These variance approximations reflect the role that stand characteristics and expansion factor play in either sampling procedure. Validation of the estimated variances was done through a sampling simulation. Most of the variance approximations were considered unbiased and good in the estimation of their respective variances; only in plot samples with expansion factors of 5 was this not true. The variance approximation was considered best at expansion factor 40; with each decreasing expansion factor value, the approximations were less accurate in estimating the variance. Across the range of expansion factor values, point sampling approximations were generally more accurate than plot sampling approximations in estimating the variance; overall, the point sample variance approximation for total basal area per acre performed the best. Variance approximations were used with a cost analysis in order to select the optimal expansion factor and number of sampling positions. Plot samples require a higher expansion factor than point samples when the number of trees per acre is greater than the total basal area per acre for variances of either characteristic. For the same expansion factor, little difference existed between the optimal number of sampling positions required in either sampling method when variances were minimized. When cost was minimized, generally fewer plots than points are needed in stands where the average dbh is less than 13.5 inches. / Master of Science

In the 1950’s and 1960’s, studies of two old-growth forest stands in Versailles State Park, Laughery Bluff and Dogwood Nature Preserves, were designed and carried out by Potzger to provide the baseline necessary to investigate future trends in these forest communities. In 1968 and 1988, Jackson surveyed these stands again and identified changes in attributes and size classes over that 20-year period. In 2011 and 2012, these sites were re-sampled to document change in species composition and stand structure since 1968. Diameter at breast height (dbh) and species identification were recorded for all stems with dbh ≥ 10 cm. Trees between 1 and 9.9 cm dbh were sampled by counting the number of individuals by species. These data were used to calculate density, dominance, and importance values, as well as to provide full-census data on the overstory size classes at the two sites. Notable findings since the prior studies included the continued increase of Acer saccharum in density and basal area as well as the continued loss of Cornus florida and Fagus grandifolia stems throughout both stands. / Department of Biology

Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Orman Mühendisliği Anabilim Dalı, 2008. / Kaynakça var.

Thèse de mémoire (M.Ress.Renouv.)--Université du Québec à Chicoutimi, 1997. / Document électronique également accessible en format PDF. CaQCU

Thesis (Ph. D.)--Carleton University, 2001. / Includes bibliographical references (p. 221-249). Also available in electronic format on the Internet.

Made available in DSpace on 2016-12-12T20:12:31Z (GMT). No. of bitstreams: 1 PGEF15MA037.pdf: 1832462 bytes, checksum: 01d1a5aa473cd390f7532e22a53db7e3 (MD5) Previous issue date: 2015-02-19 / The use of na appropriate volume calculation methods, wich can ensure better accuracy in determining individual volume of trees, is extremely importance in forest surveys, allows a smaller sampling intensity, given the stipulated erros with less time and labor cost. In this contexto, the aim of this study was to compare the volume calculation methods Smalian, Huber, Newton, Hohenadl (5 sections), Hohenadl )10 sections), FAO, Method sections, 19, Pressler and Sectional Standard, with the volume of trees determined by the water displacement method (Xylometer), wich is considered as true volume for Pinus taeda with age of 9, 13 and 20 years, in the municipalirty of Ponte Alta do Norte-SC. In total, were sampled 98 trees, all in according to the diferente methods, and clocked the time spent performing each method. After the trees were sectioned into logs of 3.10 meters, classified in assortment and applied the technique xylometer. Were fit the fifth-degree polynominal using the data obtained in each volume calculation method, checking what method provided the best fit and estimate the quantity in relation to xylometer. We used the completely randomized designs (CRD), with each tree set up a repetition of data and each cube of a treatment method. Bartlett s homogeneity rtest and analysis of variance (ANOVA) was applied to all ages, followed by the Tukey testa t 5% significance to compare the mean volumes and times. The analysis of variance showed significant diferentes between treatments for all ages, both the volume and for mearuting time. Independente of age, all volume calculation methods overestimated the volume of trees in relation to the real volume obtainde from the xylometer. For ages 9 and 13, volumes obtainde by volume calculation methods Huber, Pressler and Sectional Standard presented the lowest deviations compared to the xylometer with -0.08%; -0.43%, -0.97%; and 6,853%; -8.332%, -8.827% respectively. At age 20 years Hohenadl method (5 sections) showed the best precision (deviation of -1.98%) followed by Huber, Sectional Standard and Pressler, with deviations of -2.55, -2.59 and -3.03% respectively. By Tukey test, methods of sections 19, FAO, Smalian, Newton and Hohenadl (10 sections) differed its volumes compared to real volume to the age of 20 years. For the age of nine years only methods of sections 19, FAO, Smalian differed results about the real volume. To the age of 13 no method was statistically equal to the true volume. Methods FAO, Smalian and 19 sections were considered the worst methods to estimate the volume for all ages studied. Hohenadl (5 sections) was the volume calculation method of faster execution, differing from the other methods, Always with scaling of less than seconds. On the estimate of the volume of the fifth degree polynomial, the Sectional Standard method showed values to those obtained with the xylometer the three ages studied. Both Huber method as the Standard Sectional method had calculated volumes closer to the true volume determined by xylometer, and presente a time spent to achieve the very close of volume calculation methods that obtainde lowest times / O emprego de um método de cubagem adequado, que possa garantir melhor precisão na determinação do volume individual de árvores, é de suma importância nos levantamentos florestais, permite uma menor intensidade amostral, atendendo aos erros estipulados, com menor tempo e custo de trabalho. Nesse contexto, o objetivo do presente estudo foi comparar os métodos de cubagem de Smalian, Huber, Newton, Hohenadl (5 seções), Hohenadl (10 seções), FAO, Método relativo 19 seções, Pressler e Seccional Padrão, com o volume das árvores determinado por meio do método de deslocamento de água (Xilômetria), sendo este considerado como volume verdadeiro, para a espécie Pinus taeda com idades de 9, 13 e 20 anos, no município de Ponte Alta do Norte-SC. Foram cubadas 98 árvores de acordo com os diferentes métodos, sendo cronometrado o tempo gasto na execução de cada um. Após a cubagem as árvores foram seccionadas em toras de 3,10m, classificadas por sortimento e xilometradas. Foi ajustado o polinômio de quinto grau utilizando os dados obtidos em cada método de cubagem, verificando qual método proporciona o melhor ajuste e estimativa do volume em relação ao xilômetro. Foi empregado o Delineamento Inteiramente ao Acaso (DIC), sendo que cada árvore configurou uma repetição de dados e cada método de cubagem um tratamento. O teste de homogeneidade de Bartlett e análise de variância (ANOVA) foram aplicados para todas as idades, seguidos do teste de Tukey a 5% de significância para comparar as médias dos volumes e dos tempos. A análise de variância constatou diferença significativa entre os tratamentos de todas as idades, tanto para o volume como para o tempo de medição. Independente da idade, todos os métodos de cubagem superestimaram os volumes das árvores em relação ao volume verdadeiro obtido com a xilometria. Para as idades de nove e treze anos, os volumes obtidos pelos métodos de cubagem de Huber, Pressler e Seccional Padrão apresentaram os menores desvios comparado com o xilômetro, com -0,08%; -0,43% e -0,97%; e 6,853%; -8,332% e -8,827% respectivamente. Na idade 20 anos o método de Hohenadl (5 seções) apresentou a melhor precisão (desvio de -1,98%) seguido dos métodos de Huber, Seccional Padrão e Pressler, com desvios de -2,55, -2,59 e -3,03% respectivamente. Pelo teste de Tukey, os métodos de 19 seções, FAO, Smalian, Newton e Hohenadl (10 seções) diferiram seus volumes em relação ao volume verdadeiro para a idade de vinte anos. Para a idade de nove anos, apenas métodos de 19 seções, FAO, Smalian diferiram seus resultados em relação ao volume verdadeiro. Para a idade de 13 anos, nenhum método foi estatisticamente igual ao volume verdadeiro. Os Métodos da FAO, Smalian e 19 seções foram considerados os piores métodos na estimativa do volume para todas as idades estudadas. Hohenadl (5 seções) foi o método de cubagem de mais rápida execução, diferindo dos demais métodos, com tempo de cubagem sempre inferior a 60 segundos. Na estimava do volume pelo polinômio de quinto grau, o método Seccional Padrão apresentou valores mais próximos aos obtidos com a xilometria nas três idades em estudo. Tanto o método de Huber quanto o método Seccional Padrão apresentaram volumes calculados bem próximos ao volume verdadeiro determinado na xilometria, além de apresentar um tempo de medição bem próximo ao dos métodos que obtiveram os menores tempos de cubagem

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2009. / Härtill 5 uppsatser.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Lic.-avh. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2006. / Härtill 2 uppsatser.

Mémoire (M.Ress.Renouv.)--Université du Québec à Chicoutimi, 1996. / Document électronique également accessible en format PDF. CaQCU