Forests have been proposed as a means of reducing atmospheric carbon dioxide levels due to their ability to store carbon as biomass. To quantify the amount of atmospheric carbon sequestered by forests, biomass and density estimates are often needed. This study develops, implements, and tests an individual tree-based algorithm for obtaining forest density and biomass using orthophotographs and small footprint LiDAR imagery. It was designed to work with a range of forests and image types without modification, which is accomplished by using generic properties of trees found in many types of images. Multiple parameters are employed to determine how these generic properties are used. To set these parameters, training data is used in conjunction with an optimization algorithm (a modified Nelder-Mead simplex algorithm or a genetic algorithm). The training data consist of small images in which density and biomass are known. A first test of this technique was performed using 25 circular plots (radius = 15 m) placed in young pine plantations in central Virginia, together with false color othophotograph (spatial resolution = 0.5 m) or small footprint LiDAR (interpolated to 0.5 m) imagery. The highest density prediction accuracies (r2 up to 0.88, RMSE as low as 83 trees / ha) were found for runs where photointerpreted densities were used for training and testing. For tests run using density measurements made on the ground, accuracies were consistency higher for orthophotograph-based results than for LiDAR-based results, and were higher for trees with DBH ≥10cm than for trees with DBH ≥7 cm. Biomass estimates obtained by the algorithm using LiDAR imagery had a lower RMSE (as low as 15.6 t / ha) than most comparable studies. The correlations between the actual and predicted values (r2 up to 0.64) were lower than comparable studies, but were generally highly significant (p ≤ 0.05 or 0.01). In all runs there was no obvious relationship between accuracy and the amount of training data used, but the algorithm was sensitive to which training and testing data were selected. Methods were evaluated for combining predictions made using different parameter sets obtained after training using identical data. It was found that averaging the predictions produced improved results. After training using density estimates from the human photointerpreter, 89% of the trees located by the algorithm corresponded to trees found by the human photointerpreter. A comparison of the two optimization techniques found them to be comparable in speed and effectiveness. / Ph. D.

Accounting for competition effects is an essential step in building any stand growth simulator. However, accurate modelling of competition effects depends upon a clear understanding of quantitative relationships of various aspects of stand dynamics, including distributional parameters and spatial statistics. This study addressed four aspects of competition effects: 1) competition effects on distributional parameter dynamics of tree size variables; 2) inter-specific (loblolly pine vs. hardwood) and intra-specific competition effects on basal area growth, 3) dynamics of spatial statistical characteristics of DBH and total height, and their relevance to intertree competition, 4) and spatial properties of competition measures by available stand simulators for loblolly pine (<i>Pinus taeda</i> L.) plantations. Competition was found to affect the distribution parameters such as coefficient of variation, skewness, and the general shapes of distributions for diameter measurements, total height, crown width and crown height. Competition expedites size differentiation and thereby increases distribution variability for all variables except crown height. Intertree competition also drives skewness of these variables negative, although the distributions of crown heights tends to be more symmetric. Normality assumption generally holds for diameter measurement, but distributions of total height and crown width deviate from, and those of crown height approach, normality with intensified competition. A set of competition driven equations was developed for the distribution parameters and was validated. The differences of distribution parameters among the variables studied could be attributed to their biological meanings. / Ph. D.

Fertilization is a common, cost effective treatment for increasing forest productivity within managed forests of the southeastern United States. However, little is known about how fertilization affects the below-ground processes that drive soil CO2 efflux in loblolly pine (Pinus taeda L.). A thorough understanding of below-ground carbon dynamics is necessary for the estimation of net ecosystem productivity and the carbon storage potential of these managed systems. In April 2004, we began monitoring total soil CO2 efflux (EC), heterotrophic (RH), and root respiration (RR) in response to fertilization with diammonium phosphate (DAP). Respiratory components were measured prior to fertilization, weekly following fertilization, and bi-weekly after respiratory components stabilized using a dynamic closed chamber and an infrared gas analyzer. We found that EC differed significantly (P<0.0001) between fertilized and unfertilized plots, but the direction was dependent on date. In the early period of the study, fertilized plot values were lower than control plots. However, by the latter periods fertilized plot values returned to control levels except for one sampling date in March 2005 when fertilized plot values were greater then control plots. Heterotrophic respiration was consistently and significantly (P=0.0002) lower in fertilized plots. Root respiration was significantly (P=0.0597) increased in fertilized plots when analyzed over the study and showed a 20% increase due to fertilization. We concluded that an increase in RR and possibly root biomass was enough to balance the decrease in RH leading to no difference in EC later in the growing season. We performed a pair of greenhouse studies to observe the effects of fertilization in the form of diammonium phosphate (DAP) on RR. The objectives were to determine how nutrient additions initially affect RR in one-year-old loblolly pine seedlings. Secondly, we wanted to determine if Captan [N-(trichloromethylthio) cyclohex-4-ene-1, 2-dicarboximide], a mild fungicide, could be used to reduce or eliminate ecto-mycorrhizae upon visual inspection. Both studies showed that initially, at a high rate (100 ppm N and 49 ppm P) of fertilization, RR was significantly (P<0.10) increased relative to seedlings that did not receive fertilization. This increase was only temporary with rates returning to, or decreasing below, control levels by the end of the study. No consistent trend was found between low (25 ppm N and 13 ppm P) and moderate (50 ppm N and 25 ppm P) rates of fertilization. Captan was shown to generally have no affect on RR. Captan and fertilization both showed (visual inspection) a decrease in fine-roots and mycorrhizae, which could explain the reduction in respiration rates observed in these treatments by the end of the studies. / Master of Science

Intensive site preparation practices and their effect on nitrogen cycling have been implicated as possible causes of productivity declines on forest sites in Australia and New Zealand. This study was initiated in order to determine the effects of site preparation intensity upon N distribution and availability in loblolly pine (Pinus taeda L.) plantations in Virginia. In the summer of 1982, three forest sites at the Reynolds Homestead Research Center on the Virginia Piedmont were clearcut. In the fall of the same year all three sites were prepared for planting using one of the following treatments: 1. shear, rake, disk (S,R,D) (3-passes); 2. shear-disk (S-D) (1-pass); and 3. chop, burn (C,B) (high intensity burn). During March of 1983, 1-0 genetically improved loblolly pine seedlings were planted on all sites. Pine biomass was greatest on the S,R,D area after three growing seasons. Total biomass and N content (NCONT) of native vegetation and forest floor were greatest in the S-D area. Total N in the upper 15 cm of mineral soil was also greatest in the S-D area. Total system N was highest in the S-D area and this treatment is more N-conservative than either of the more intensive treatments. During the third growing season potentially mineralizable N levels were highest on the two disked treatment areas, 157 and 144 kg N/ha for the s-o, and S,R,D areas, respectively. Pine foliar nutrient concentrations determined after the second and third growing seasons provided no evidence of existing or impending nutrient deficiencies. These results show that short-term pine nutrition and growth were not adversely affected by reductions of N capital on these sites. However, if wasteful practices, such as raking and burning with high intensity fires, are also used to establish subsequent stands on these same sites, cumulative losses of N could result in productivity declines. / M.S.

I evaluated effects of 5 intensive pine plantation establishment regimes during years 1 – 5 post-establishment on vegetation communities, loblolly pine (Pinus taeda) growth, nutritional carrying capacity for white-tailed deer (Odocoileus virginianus), habitat values for northern bobwhite (Colinus virginianus), and projected financial viability in the Lower Coastal Plain of Mississippi. Treatments were combinations of mechanical site preparation (MSP), chemical site preparation (CSP), and herbaceous weed control (HWC) designed to reflect the range of operational intensities on industrial forest lands in the southeastern U.S. Results should inform plantation management decisions throughout the region. Pine growth increased with greater treatment intensity. At age 5, trees in the most intensively managed treatment were 1.5 m taller than those in the least intensive treatment. Mechanical site preparation improved growth by alleviating soil physical problems. Growth and yield projections indicated that increased fiber yield may not justify investment in more intensive regimes; financial analysis favored the least expensive treatment, though all regimes produced potential internal rates of return > 9% when managed to financial maturity. Use of MSP with banded HWC yielded abundant low-quality deer forage sufficient for body maintenance; nutritional needs for lactating does were better served by CSP with banded HWC. Broadcast HWC reduced biomass of high-quality forbs. In this region of limited soil nutrients and abundant low-quality forages, the optimal combination of maintenance-level and lactation-level nutrition was provided by CSP or CSP and MSP combined with banded HWC. I evaluated vegetation communities for nesting, loafing, brood-rearing, and fall and winter food suitability for northern bobwhite. No treatment provided brood-rearing habitat due to combined lack of bare ground and forb coverage. Fall and winter feeding, nesting, and loafing cover were best produced by MSP and CSP combined with banded HWC. However, lack of brood-rearing cover may reduce or eliminate usable space in all treatments. Differences between vegetation communities were caused by use of CSP, which eliminated many residual woody and vine species, and by differences in broadcast versus banded HWC. Herbicide use decreased plant diversity and species richness, and impacted successional trajectory. Community differences persisted through year 5.

Visando caracterizar a dinâmica de crescimento do Pinus taeda no sul do Brasil, este estudo teve os seguintes objetivos: i) determinar os principais fatores edafo-climáticos e do povoamento associados à ampla variação de produtividade da espécie; e ii) caracterizar padrões de crescimento e uniformidade, do plantio até 9 anos em diferentes regiões edafoclimáticas. Para isso, foram selecionadas 24 parcelas sem desbaste (700m²), com aproximadamente 1450 árvores ha-1, entre 8 a 10 anos de idade, do projeto PPPIB (Produtividade Potencial do Pinus no Brasil), as quais estão localizadas em Jaguariaíva-PR, Ponta Grossa-PR, Rio Negrinho-SC e Três Barras-SC. O clima destas regiões é temperado úmido, com precipitação média anual de 1477mm, com temperaturas máxima, média e mínima de 24,3ºC, 17,9ºC e 12,7ºC. Todas as variáveis biométricas foram determinadas através do banco de dados de inventário (2006-2009), dados de cubagem, análise de tronco (discos), de anéis de crescimento (baguetas) e massa específica aparente (densitometria de raios-X). Coletaram-se solos (0-20cm) nas parcelas de inventário, e obtiveram-se os dados climáticos de estações meteorológicas locais. Através das análises de disco determinaram-se os índices de sítio (idade base 10 anos), e através da bagueta e densitometria de raios-X, estimaramse o padrão de crescimento de todas as parcelas em volume (m³ha-1) e matéria seca (Mgha-1) e seus Incrementos Médios Anuais e Correntes Anuais até o 9º ano. A uniformidade foi avaliada através do coeficiente de variação de volume das árvores dentro das parcelas (CVV) e da percentagem de biomassa em 50% das árvores mais finas (PB50), dos 2 aos 9 anos. As regiões apresentaram grande variação das propriedades físico-químicas do solo, como profundidade (30-140cm), teor de matéria orgânica (23 a 65g dm-3), teor de argila (20 a 85%), quantidade de N (500 a 5300kg ha- 1), e quantidade de P (9 a 84kg ha-1). Aos 9 anos de idade todas parcelas não haviam culminado seu crescimento, e o incremento médio anual com casca (IMAc9), o estoque de biomassa do lenho e índice de sítio de idade base 10 (IS10) variaram de 15 a 35m³ ha-1 ano-1, de 55 a 130Mg ha-1, e 12 a 19m, respectivamente, com maiores valores em Três Barras. Esta caracterização não era possível de ser detectada antes do 6º ano, mostrando que as decisões silviculturais ou genéticas precoces em Pinus precisam ser cuidadosamente consideradas. A produtividade (IMA) foi positivamente relacionada com o IS10, e ambos estiveram relacionados com os maiores teores de matéria orgânica do solo, quantidade de nitrogênio disponível e menores médias de temperatura mínima e déficit hídrico. As florestas mais produtivas se mostraram também mais uniformes (menores CVV e maiores PB50), mas confundidas com material genético superior. Assim, o estudo corrobora o papel dos nutrientes, solos de boa drenagem, e condição climática amena e com baixo déficit hídrico na explicação da elevada produtividade do P.taeda no sul do Brasil, comparativamente a sua região de origem. Baseado nestes resultados, estudos de fertilização, material genético e uso rotineiro de análise do tronco, associado à densitometria de raios-X, podem ser recomendados para o P. taeda. / The study was designed to characterize the growth dynamics of Pinus taeda in south of Brazil and had the following objectives: i) determine the main edaphic, climatic and stand factors associated with the range in productivity of the species; and ii) characterize the growth patterns and uniformity, from planting until 9 years-old, across different edaphic and climatic regions. A total of 24 unthinned plots were selected (700m2), with stocking of 1450 trees ha-1, between 8 and 10 years old, from the PPPIB project (Pine Potential Productivity in Brazil), and are located in Jaguariaíva-PR, Ponta Grossa-PR, Rio Negrinho-SC and Três Barras-SC. The climate of these regions is temperate humid (Cfb), with mean annual precipitation of 1477mm, and maximum, mean and minimum temperatures of 24.3ºC, 17.9ºC e 12.7ºC. The biometric variables were assessed using inventory datasets (2006-2009), destructive sampling, bole analysis (disks), growth rings (stem coring), and specific gravity (X-ray densitometry). Soil samples (0-20cm) were collected on inventory plots, and climatic data were obtained from local weather stations. Site index (base age 10 years) were determined using bole disks, and growth patterns of all plots (m3ha-1), dry mass (Mgha-1), mean and current annual increments until 9th year were determined using stem coring and X-ray densitometry. Stand uniformity was evaluated using tree volume coefficient of variation within plots (CVV) and percentage of biomass for the 50% thinnest trees (PB50), from ages 2 to 9. Regions showed a wide range of soil physical and chemical properties, such as soil depth (30-140cm), organic matter levels (23 a 65g dm-3), clay content (20 a 85%), amount of N (500 a 5300kg ha-1), and amount of P (9 a 84kg ha-1). At 9 years old all the plots did not reached their maximum growth; and mean annual increment with bark (IMAc9), standing stem biomass and site index at base age 10 (IS10) ranged from 15 to 35m³ ha-1 year-1, 55 to 130Mg ha-1, and 12 a 19m, respectively, with higher values on Tres Barras region. This characterization was not possible to be detected before the 6th year, showing that early silvicultural and genetic decisions in Pinus need to be carefully considered. The productivity (IMAc9) was positively related with IS10, and both were related with higher levels of soil organic matter and available nitrogen, and with lower averages of minimum temperatures and water deficit. The most productive forests showed to be more uniform also (lower CVV and higher PB50), but confounded with superior genetic material. Therefore, the study corroborates with the role of nutrients, well drained soils, mild climatic conditions and low water deficit to explain the high yileds of P.taeda in Brazil, comparatively to its original region. Based on these results, studies of fertilization, genetic material and more frequent use of bole analysis, associated with X-ray densitometry, might be recommended for P. taeda.

Visando caracterizar a dinâmica de crescimento do Pinus taeda no sul do Brasil, este estudo teve os seguintes objetivos: i) determinar os principais fatores edafo-climáticos e do povoamento associados à ampla variação de produtividade da espécie; e ii) caracterizar padrões de crescimento e uniformidade, do plantio até 9 anos em diferentes regiões edafoclimáticas. Para isso, foram selecionadas 24 parcelas sem desbaste (700m²), com aproximadamente 1450 árvores ha-1, entre 8 a 10 anos de idade, do projeto PPPIB (Produtividade Potencial do Pinus no Brasil), as quais estão localizadas em Jaguariaíva-PR, Ponta Grossa-PR, Rio Negrinho-SC e Três Barras-SC. O clima destas regiões é temperado úmido, com precipitação média anual de 1477mm, com temperaturas máxima, média e mínima de 24,3ºC, 17,9ºC e 12,7ºC. Todas as variáveis biométricas foram determinadas através do banco de dados de inventário (2006-2009), dados de cubagem, análise de tronco (discos), de anéis de crescimento (baguetas) e massa específica aparente (densitometria de raios-X). Coletaram-se solos (0-20cm) nas parcelas de inventário, e obtiveram-se os dados climáticos de estações meteorológicas locais. Através das análises de disco determinaram-se os índices de sítio (idade base 10 anos), e através da bagueta e densitometria de raios-X, estimaramse o padrão de crescimento de todas as parcelas em volume (m³ha-1) e matéria seca (Mgha-1) e seus Incrementos Médios Anuais e Correntes Anuais até o 9º ano. A uniformidade foi avaliada através do coeficiente de variação de volume das árvores dentro das parcelas (CVV) e da percentagem de biomassa em 50% das árvores mais finas (PB50), dos 2 aos 9 anos. As regiões apresentaram grande variação das propriedades físico-químicas do solo, como profundidade (30-140cm), teor de matéria orgânica (23 a 65g dm-3), teor de argila (20 a 85%), quantidade de N (500 a 5300kg ha- 1), e quantidade de P (9 a 84kg ha-1). Aos 9 anos de idade todas parcelas não haviam culminado seu crescimento, e o incremento médio anual com casca (IMAc9), o estoque de biomassa do lenho e índice de sítio de idade base 10 (IS10) variaram de 15 a 35m³ ha-1 ano-1, de 55 a 130Mg ha-1, e 12 a 19m, respectivamente, com maiores valores em Três Barras. Esta caracterização não era possível de ser detectada antes do 6º ano, mostrando que as decisões silviculturais ou genéticas precoces em Pinus precisam ser cuidadosamente consideradas. A produtividade (IMA) foi positivamente relacionada com o IS10, e ambos estiveram relacionados com os maiores teores de matéria orgânica do solo, quantidade de nitrogênio disponível e menores médias de temperatura mínima e déficit hídrico. As florestas mais produtivas se mostraram também mais uniformes (menores CVV e maiores PB50), mas confundidas com material genético superior. Assim, o estudo corrobora o papel dos nutrientes, solos de boa drenagem, e condição climática amena e com baixo déficit hídrico na explicação da elevada produtividade do P.taeda no sul do Brasil, comparativamente a sua região de origem. Baseado nestes resultados, estudos de fertilização, material genético e uso rotineiro de análise do tronco, associado à densitometria de raios-X, podem ser recomendados para o P. taeda. / The study was designed to characterize the growth dynamics of Pinus taeda in south of Brazil and had the following objectives: i) determine the main edaphic, climatic and stand factors associated with the range in productivity of the species; and ii) characterize the growth patterns and uniformity, from planting until 9 years-old, across different edaphic and climatic regions. A total of 24 unthinned plots were selected (700m2), with stocking of 1450 trees ha-1, between 8 and 10 years old, from the PPPIB project (Pine Potential Productivity in Brazil), and are located in Jaguariaíva-PR, Ponta Grossa-PR, Rio Negrinho-SC and Três Barras-SC. The climate of these regions is temperate humid (Cfb), with mean annual precipitation of 1477mm, and maximum, mean and minimum temperatures of 24.3ºC, 17.9ºC e 12.7ºC. The biometric variables were assessed using inventory datasets (2006-2009), destructive sampling, bole analysis (disks), growth rings (stem coring), and specific gravity (X-ray densitometry). Soil samples (0-20cm) were collected on inventory plots, and climatic data were obtained from local weather stations. Site index (base age 10 years) were determined using bole disks, and growth patterns of all plots (m3ha-1), dry mass (Mgha-1), mean and current annual increments until 9th year were determined using stem coring and X-ray densitometry. Stand uniformity was evaluated using tree volume coefficient of variation within plots (CVV) and percentage of biomass for the 50% thinnest trees (PB50), from ages 2 to 9. Regions showed a wide range of soil physical and chemical properties, such as soil depth (30-140cm), organic matter levels (23 a 65g dm-3), clay content (20 a 85%), amount of N (500 a 5300kg ha-1), and amount of P (9 a 84kg ha-1). At 9 years old all the plots did not reached their maximum growth; and mean annual increment with bark (IMAc9), standing stem biomass and site index at base age 10 (IS10) ranged from 15 to 35m³ ha-1 year-1, 55 to 130Mg ha-1, and 12 a 19m, respectively, with higher values on Tres Barras region. This characterization was not possible to be detected before the 6th year, showing that early silvicultural and genetic decisions in Pinus need to be carefully considered. The productivity (IMAc9) was positively related with IS10, and both were related with higher levels of soil organic matter and available nitrogen, and with lower averages of minimum temperatures and water deficit. The most productive forests showed to be more uniform also (lower CVV and higher PB50), but confounded with superior genetic material. Therefore, the study corroborates with the role of nutrients, well drained soils, mild climatic conditions and low water deficit to explain the high yileds of P.taeda in Brazil, comparatively to its original region. Based on these results, studies of fertilization, genetic material and more frequent use of bole analysis, associated with X-ray densitometry, might be recommended for P. taeda.

The specific objectives of this project were: 1) Determine financial viability of enrolling forest landowners in Chicago Climate Exchange (CCX) forestry carbon offset protocols; 2) Determine financial trade-offs associated with managing loblolly pine (Pinus taeda L.) and Cherrybark oak (Quercus pagoda Raf.) stands for increased carbon sequestration and timber; 3) Examine financial feasibility of increasing carbon accumulation in wood products carbon by extending rotation length of loblolly pine stands; and 4) Explore potential impacts of carbon policies and programs on future carbon accumulation in Mississippi’s forest sector.

Decades of tree improvement has resulted in genetic gains in loblolly pine productivity, form, and resistance to fusiform rust. The goal of this study was to advance the understanding and applied use of genetic improvement by analyzing inter- and intra-provenances hybrids’ rust resistance and evaluating midrotation performance of varying levels of genetically improved stock types. The first study compares 16 seedlots at the USDA Resistance Screening Center and evaluates rust resistance of controlled-pollinated inter- and intra-provenances crosses, and openpollinated seedlots from three provenances: Western Gulf, Atlantic Coastal, and Interior Piedmont. Post inoculation, one Coastal OP seedlot was resistant and ten of the seedlots were susceptible to the disease. The second study compares three levels of improved stock types: second-generation open-pollinated, controlled pollinated, and varietal material. After the fifteenth growing season, all three improved stock types were not significantly different from one another in defects, height, diameter, volume, and exhibited site index.

Appropriate management of mid-rotation pine plantations can improve habitat for early successional and pine-grassland adapted avian species. I tested effects of Imazapyr selective herbicide and prescribed fire on plant and avian communities in thinned, mid-rotation pine stands contracted under the Conservation Reserve Program. Within 12 replicate sites, 2 8.1-ha plots were assigned either herbicide and prescribed fire treatment or control. I described components of vegetation structure and composition in 2006. I tested effects of herbicide and prescribed fire treatment on avian relative abundance, species richness, total avian conservation value, and density of select species during 2003 - 2006. Hardwood midstory decreased and abundances of grasses and forbs increased following treatment. A shift occurred in the bird community from closed-canopy forest species to early successional and pine-grassland species. Treatment stands benefited many avian species exhibiting negative population trends.