Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 15, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. David Larsen Vita. Includes bibliographical references.

Thesis (M.S.)--Oregon State University, 1997. / Typescript (photocopy). Includes bibliographical references (leaves 148-152). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 38-42). Also available on the World Wide Web.

No description available.

The canopy cover of the Pinus contorta forests of west-central Alberta, dictates colonization of the forest floor ground layer. This dynamic ground layer is a mosaic of feather mosses and reindeer lichens in a system driven by disturbance. In this project, anthropogenic was used to control canopy cover change and study its effects on the ground layer. Timber companies selectively mechanically thinned sections producing three experimental areas with uncut controls. Data were collected from 182, 6.5 m2 plots located in the four thinning areas. Six general areas of inquiry were posed around determining ground layer responses to canopy opening: 1) vegetation, 2) plant species richness, 3) plant abundance, 4) diaspore availability, 5) environmental limiting factors, 6) moss and lichen establishment. In 1997, three timber companies were involved in selective tree removal at three different stand percentages (20/40/60%), however, these were not consistent when measured in 2005. This variation in operational logging along with changes over the seven year time period, resulted in strong disparity for each of the thinning regimes. Percent canopy cover change for all thinned plots was ranked and three new groups created; least, moderate, most canopy change. These new groups formed the basis for the data presented in Chapter 3. The three thinning groups had little to no effect on species richness, but overall showed a small decrease from measurements taken pre-harvest. Numbers of locally rare species were similar to pre-harvest levels, but there were some gains and losses of species between pre-harvest and seven years post-harvest. In contrast to the lack of change in diversity, the abundance of dominant species and major vegetation components underwent dramatic changes. Dominant species of both vascular plants and bryophytes decreased with increasing canopy openness, with vascular plants being gradually affected while mosses were more affected at less intense canopy opening. Abundances of lichens showed no change. When measuring limiting factors (biotic and abiotic) for ground layer mosses and lichens, diaspores (spores and fragments) were plentiful in all stands, but differed in abundance at the micro-scale. The position of feather mosses and reindeer lichen in the forest floor mosaic appears to be due to an intermingling of environmental influences (at both the meso- and micro-scale). With less environmental constraints on lichens and the widespread availability of lichen fragments, lichens are more tolerant to the conditions evoked by thinning than are mosses. Mosses are more restricted by environmental conditions and have more constrained diaspore dispersal than lichens. Thus, mosses are more limited both by diaspore dispersal and by harsh environmental conditions in open canopy habitats. Whereas relative humidity (RH) did not differ at the stand level, moss dominated areas had higher RH no matter where they occurred, lichen-dominated areas did not--suggesting the moss occurrence is at least partially controlled by micro-scale level factors. Moss establishment is effected by the "ghosts" of past events and substrates. Mosses are widespread in formerly moss-dominated areas that contain organic substrates and high canopy cover. Lichen establishment is limited in previously moss-dominated areas. Species interactions weighed more heavily on moss establishment than on that of lichens. Therefore, the effects of canopy change on the ground layer are variable corresponding to moss decreases, but not lichens. Seven years post-harvest species diversity is unchanged, but vegetation, as a whole, has been affected.

Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-17T17:57:49Z No. of bitstreams: 1 AUDERLAN DE MACENA PEREIRA - DISSERTAÇÃO PPGHT 2015..pdf: 1586819 bytes, checksum: 084746639c19ffdff497fc898a95667a (MD5) / Made available in DSpace on 2018-05-17T17:57:49Z (GMT). No. of bitstreams: 1 AUDERLAN DE MACENA PEREIRA - DISSERTAÇÃO PPGHT 2015..pdf: 1586819 bytes, checksum: 084746639c19ffdff497fc898a95667a (MD5) Previous issue date: 2015 / O meloeiro tem se destacado no Nordeste em razão das condições de solo e clima que favorecerem o cultivo dessa olerícola. É uma planta da família das cucurbitáceas que permite várias formas de manipulação da relação entre a fonte e o dreno por meio de seu manejo cultural. Uma possibilidade de alterar a relação fonte:dreno no meloeiro seria a utilização do agrotêxtil (tecido não tecido) em diferentes épocas, associada com a fixação de diferente número de frutos por planta. O trabalho teve como objetivo avaliar a partição de assimilados, a produtividade e a qualidade de frutos do meloeiro quando submetidos à retirada do agrotêxtil em diferentes épocas e fixação de fruto na planta. O experimento foi realizado no Centro de Ciências e Tecnologia Agroalimentar (CCTA/UFCG) durante o período de agosto a dezembro de 2014, com plantas do híbrido de melão Cantaloupe Hopey King, no espaçamento de 2,0 x 0,8 m em Pombal - PB. O delineamento experimental foi o de blocos casualizados com os tratamentos alocados em um arranjo em parcelas subdivididas (5x3), onde na parcela constaram de diferentes épocas de retirada do agrotêxtil (20, 24, 28, 32, e 36 dias após o transplante), e na sub parcela de diferentes fixações de frutos na planta (1 fruto, 2 frutos e fixação livre) em oito repetições, sendo quatro utilizadas para as avaliações de crescimento e quatro para a produção e qualidade dos frutos. Avaliou-se neste trabalho a quantificação da expressão do sexo, o crescimento e a partição de assimilados, a produção e a qualidade dos frutos. A retirada do agrotêxtil em diferentes épocas e o número de frutos por plantas afetaram significativamente a relação fonte:dreno. As épocas de retirada do agrotêxtil e a fixação fruto promoveram alterações no crescimento, produção e qualidade dos frutos do meloeiro. O atraso na retirada do agrotêxtil de 20,0 para 36,0 DAT proporcionaram maiores número de flores hermafroditas, massa seca da folha e da parte aérea, área foliar e redução nos sólidos solúveis totais. A frutificação livre na planta reduziu o número de flores hermafroditas e elevou a massa seca do fruto e índice de colheita. A massa do fruto e a produtividade da cultura atingiu o máximo valor com a retirada do agrotêxtil aos 26,6 e 25,1 DAT, respectivamente. Plantas com um e dois frutos apresentaram maior massa, porém com menor produtividade, se comparado a plantas com fixação livre de frutos. A utilização do agrotêxtil a partir dos 25 DAT dificultou as práticas culturais como capinas e penteamneto das plantas devido ao entrelaçamento de ramas dentro do túnel ocasionando maior queda de flores e reduzindo a produtividade da cultura. / The melon has excelled in the Northeast because of soil and climate conditions that favor the cultivation of this vegetable crop. It is a plant of the Cucurbitaceae family which allows various forms of manipulation of the relationship between the source and the drain by means of their cultural practices. A possibility to change the font ratio: drain the melon would be the use of the agrotextile (nonwoven fabric) at different times associated with fixing different number of fruits per plant. The study aimed to assess the assimilated partition, productivity and the quality of the melon fruit when subjected to removal of the nonwoven at different times and setting fruit in the plant. The experiment was conducted in the Science Center and Agrifood Technology (CCTA / UFCG) during the period from August to December 2014, with melon hybrid plants Cantaloupe Hopey King in the spacing of 2.0 x 0.8 m in Pombal - PB. The experimental design was a randomized block with treatments assigned to a split plot arrangement (5x3), which consisted in part of different periods of withdrawal of the row cover (20, 24, 28, 32, and 36 days after transplantation) and sub plot of different fruits fixings in the plant (1 fruit, 2 fruit and free) in eight repetitions, four used for the growth of reviews and four for the production and fruit quality. It was evaluated in this study to quantify the expression of sex, growth and assimilated partition, production and fruit quality. The withdrawal of agrotextile at different times and the number of fruits per plant significantly affected the supply relationship: drain. The withdrawal times of the nonwoven and fruit fixation promoted alterations in the growth, production and fruit quality of melon. The delay in the withdrawal of agrotextile 20.0 to 36.0 DAT provided higher number of hermaphrodite flowers, dry weight of leaf and shoot, leaf area and reduction in soluble solids. Free fruiting in the plant reduced the number of hermaphrodite flowers and raised the dry matter of the fruit and harvest index. The fruit mass and crop yield peaked with the removal of agrotextile to 26.6 and 25.1 DAT, respectively. Plants with one and two fruits presented greater mass but with lower productivity compared to plants with fruits of free determination. The use of nonwoven from 25 DAT difficult cultural practices as weeding and combing plants due to the intertwining branches into the tunnel leading to higher drop flowers and reducing crop yield

Proper management of uneven-aged interior Douglas-fir (Pseudotsuga menziesii var. glauca) stands is important for British Columbia’s central and southern interior. These stands constitute one of main components of the operable forest land in these areas, with easy access from main roads and towns. This study focused on the growth of uneven-aged Douglas-fir stands after pre-commercial thinning (spacing), with an impetus to improve upon current management practices. Data were collected from 24 permanent sample plots which were established near Williams Lake, British Columbia in 1989; thinning took place between 1990 and 1991. Three measurements have been made post-treatment: 1993, 1997 and 2004. The plot data were used to analyze different growth responses among three different spacing regimes (standard, 3 m clumped and 5 m clumped spacing) and a control. Analyses were performed at both the stand and tree level. The growth of basal area per ha, quadratic mean dbh, volume per ha and Lorey’s height were used for stand level analyses. At the tree level, dbh, height, basal area and volume were the variables of interest. At the stand level, mortality increased (7.1 to 107.1 stems/ha) and ingrowth decreased (2.4 to 8.6 stems/ha) for the second growth period (1997-2003), compared to the first growth period (5.8 to 107.1 stems/ha and 5.0 to 12.4 stems/ha, respectively). No significant differences in annual growth of quadratic mean dbh, basal area and volume per ha and Lorey’s height were noted between the different spacing regimes and the control. At the individual tree level, the 5 m clumped spacing regime usually had the highest dbh, basal area and volume growth for both growth periods. The one exception was for height growth, when analyzed using mixed-effects modeling, where no significant differences were found. Trees on the other two spacing regimes also had higher growth in dbh, basal area, and volume than trees on the control plots. The positive growth response to the spacing treatments at the single tree level was obtained without a reduction in growth at the stand level. This growth increase will result in the residual trees reaching larger sizes more quickly than they would have with no treatment, leading to improved mule deer winter range habitat and higher timber values. / Forestry, Faculty of / Graduate

The study examined the goal fulfillment in edge zones along rivers and lakes in precommercial thinning stands based on national targets which is the basis for Swedish forestry. Pre-commercial thinning has a major impact on the future forest, as it determines how the tree species distribution will turn out. The study was conducted as a field study in February 2018 based on 30 precommercial thinning sites, aged 5–15 years, in connection to rivers and / or lakes. Of these, 25 rivers and five lakes were surveyed. 22 of the surveyed stands were privately owned and 8 were company-owned forests. The edge zones had between 0–100% shadowing of the water surface. Few sites with soil damage were detected and also a varying amount of tree species and deadwood. The most common deadwood was standing and lying dead wood with a diameter of 10 cm for both company and privately-owned forests. The percentage of number of stems per ha of deciduous trees in the edge zones was 52%, Norway spruce 41% and Scots pine 7% respectively. Within the edge zones, the sample areas closest to rivers and lakes had 55% of number of stems per ha deciduous trees, 40% spruce and 6% pine. In the sample areas closest to the stand, the number of deciduous trees was 48%, spruce 44% and pine 9%. Company-owned forests had more spruce (59%) along the waterfront compared to privately owned forests, who had a significantly higher proportion of deciduous trees (61%). By actively working with the composition of the edge zones, creating deadwood, saving trees for shadow and by thinning dense areas, particularly spruce-dominated, increased biodiversity can be achieved. Dense, spruce-dominated areas are those areas where the goal fulfillment is insufficient in many places.

A three-year study was conducted at a commercial vineyard site in California’s Edna Valley AVA to evaluate the physiological and agronomical effects of the timing of cluster thinning on Pinot noir (clone 115) grapevines. Vines were thinned to one cluster per shoot at three selected time-points during the growing season (bloom, bloom + 4 weeks, bloom + 8 weeks), and fruit from each treatment was harvested and made into wine. Across all growing seasons, yield decreased 43% in thinned vines relative to un-thinned control vines. No effect of cluster thinning or interaction with growing season was found in vine shoot diameter, internode length, fruit zone light level, or cluster weight. Growing season significantly affected more fruit and wine parameters than did cluster thinning treatment, with interactions between treatment and growing season found in fruit Brix, titratable acidity, and anthocyanins, as well as wine anthocyanins and wine b* (yellow component). For example, bloom + 8 and bloom + 12 thinning treatments advanced Brix in 2017 but had no effect in 2018. Cluster thinning treatments increased berry anthocyanins by 43% in 2017 and by 103% in 2018 relative to the control. Similarly, cluster thinning increased berry total phenolics by 87% in 2017 and by 140% in 2018 relative to the control, with no significant differences found between the different thinning treatments. However, the levels of anthocyanins and total phenolics were generally not affected by cluster thinning treatment in the resulting wines. The fact that different cluster thinning treatments resulted in nil or minor effects on fruit and wine suggests that the vines tested were at or below a balanced crop load prior to the application of cluster thinning. Edna Valley AVA could likely support higher crop loads than 3.2 on the Ravaz index without negatively impacting fruit or wine composition and reducing crop load below that level is unlikely to increase fruit or wine quality.

Variable-density thinning (VDT) is a management option designed to increase structural heterogeneity in second-growth conifer stands. This study examined subcanopy tree growth response to two variations of VDT. At the Forest Ecosystem Study in western Washington, thinning intensity was found to have a significant effect on height growth of Douglasir (Pseudotsuga menziesii (Mirb.) Franco) seedlings which established following the thinning. At the Olympic Habitat Development Study in western Washington, basal area growth response was examined for residual midcanopy western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western redcedar (Thuja plicata ex. D. Don). Both species retained the ability to respond to thinning. The results of this study suggest that non-uniform thinning practices, like VDT, can lead to variation in growth response of residual subcanopy trees and new regeneration. This may accelerate the development of more structurally diverse forests than traditional management practices.