Although manipulation of the light regime is a common goal of silvicultural treatments, the specific light conditions created are poorly documented for many forest types and geographic locations. To help quantify effects of silivicultural treatments on light conditions, basal area, canopy structure, and photosynthetically active radiation (PAR), collected both instantaneously and across time, were measured in central hardwood forests following silvicultural treatments. These measurements were used to: 1.) investigate the magnitudes of differences in understory percent ambient PAR following implementation of shelterwood and thinning treatments; 2.) document the specific amount and variability of understory percent ambient PAR in shelterwood treatments (mean residual basal area=21 ft2/ac [4.8 m2/ha]), thinning (78 ft2/ac [17.9 m2/ha]), and untreated controls (18 ft2/ac[4.1 m2/ha); and 3.) Examine relationships between: basal area and canopy cover; basal area and measured percent ambient PAR; and canopy cover and measured percent ambient PAR. It was found that greater light levels resulted from greater canopy removals. Indexes of variability in light across time and among locations within a stand were higher in the shelterwood and thinning treatments than in the uncut control. Simple linear regression relationships were observed between basal area and PAR (r2= 0.8784 for instantaneous measurements, r2= 0.9697 for continuous measurements), and basal area and canopy cover (r2=0.8479). Such relationships provide a means for including light management in forest planning and application of silivicultural treatments.

Thinning is performed today with essentially two thinning methods, with strip-roads or stand-thinning machines. The result after thinning affects the stands future development. In this study, the two thinning methods was compared with regard to distribution of basal area, resulting damage, the distribution of stems, actual thinning intensity and the impact that these differences may provide in the future. The survey was conducted in Sundsvall, Sweden in two different stands where basal area- surfaces, number of stems, damage and thinning strength was measured. The result shows that stand-thinning machines produce less damage to the stems and a more even distribution of the basal area. The strip-road method carried out a thinning of excessive thinning intensity of 50 % compared to 30 % for stand-thinning method. From a quality point of view the stand-thinning machines performed a better result. These machines have a lower production (harvested volume per hour) which probably results in lower financial gains in thinnings. Keywords: stand-thinning, basal area, thinning strength, Vimek, soil damage.

7 pp. / Preventing catastrophic stand replacing events are best accomplished through thinning. Lower tree densities result in greater tree growth. Stands with lower tree densities have greater plant diversity. Determining stand conditions will provide a baseline for formulating a plan to improve stand conditions. Thinning around individual trees can improve individual tree health reducing the likelihood of damage from bark beetles, fire or drought.

The epiphytic lichen Usnea longissima is strongly associated with old-growth forests and is declining. Previous studies have documented unimodal relationships between stand density and abundance of U. longissima. The aim of this thesis has been to investigate whether the same relationship is found in Sweden and to determine the optimum level of stand density. The study area (1.4 ha) was divided into a grid with 48 circular plots (10-m radius). Stand density was measured as basal area (m²/ha) using a relascope and abundance of U. longissima was measured as the length of the longest thallus present on the tree nearest the plot center. Usnea longissima was found in 42 plots (mean thallus length of 37 cm). The regression analyses between length of U. longissima and basal area showed that the relationship was not significant (R²=0.082, P=0.066), and tended to be linear rather than unimodal. However, plots with U. longissima had significantly lower basal area (30.4 m²/ha) than plots without the lichen (35.1 m²/ha). The basal area in U. longissima plots was higher than in Norwegian studies, but similar to other Swedish sites. Thus, my results correspond well with earlier studies that have documented higher basal area in U. longissima-locations in Västernorrland than in more oceanic areas in Norway. Thereby a basal area around 27-35 m²/ha seems most favorable for U. longissima in the study area. The lichen cannot develop large populations in dense stands, indicating that management operations to reduce the basal area might be needed in such stands.

?rea de concentra??o: Recursos florestais. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-05-02T18:26:46Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) leovandes_soares_silva.pdf: 1592286 bytes, checksum: a9c99e41f48e73da3e46cf15e2ab8f11 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-05-16T19:49:18Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) leovandes_soares_silva.pdf: 1592286 bytes, checksum: a9c99e41f48e73da3e46cf15e2ab8f11 (MD5) / Made available in DSpace on 2017-05-16T19:49:18Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) leovandes_soares_silva.pdf: 1592286 bytes, checksum: a9c99e41f48e73da3e46cf15e2ab8f11 (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este trabalho teve como objetivo avaliar mudan?as flor?sticas e estruturais da comunidade e popula??es arb?reas em fitofisionomias de Cerrado e Floresta Estacional Semidec?dual. A ?rea de estudo se encontra situada na Fazenda Experimental do Moura, em Curvelo-MG (Cerrado stricto sensu ? CSS ? 18,84? S e 44,39? W; Cerrad?o ? CD ? 18?82?S e 44?25? W; e Floresta Estacional Semidecidual ? FES ? 18?45?S e 45? 25?W), o clima ? do tipo Aw de K?ppen e se encontra sobre substrato de Latossolos ?cidos e distr?ficos. Um primeiro invent?rio foi realizado no CSS e CD em 2010, quando foram identificados, medidos todos os indiv?duos vivos com di?metro altura do solo (DAS) ? 5,0 cm, a 0,30 m de altura do solo. J? para a FES, o primeiro invent?rio ocorreu em 2011 e foram medidos di?metros e identificados todos os indiv?duos vivos com di?metro altura do peito (DAP) ? 5,0 cm. O segundo invent?rio de todas as fitofisionomias foi realizado em 2015, foram adotados os mesmos crit?rios do invent?rio anterior, sendo remedidos os sobreviventes, registrados mortos e indiv?duos que atingiram o di?metro m?nimo de inclus?o no segundo invent?rio (recrutas) receberam placas com numera??o e foram identificados e mensurados. Em cada parcela de cada fitofisionomia foram coletados vari?veis ambientais para an?lises de correla??o de Pearson (vegeta??o e ambiente). Foram realizadas an?lises de din?mica flor?stica, estrutural e das popula??es mais abundantes, todas as esp?cies foram classificadas quanto ao status de conserva??o, densidade da madeira e dispers?o de sementes. No CSS, houve perda de uma ?nica esp?cie Zeyheria montana. As fam?lias com mais representantes Fabaceae com 13 esp?cies no primeiro invent?rio e 13 esp?cies no segundo invent?rio respectivamente, seguidos de: Bignoniaceae (6 e 5), Vochysiaceae (5 e 5) e Malpighiaceae (4 e 4), respectivamente. J? no CD, foram contabilizados (36 e 34) fam?lias, (74 e 69) g?neros (100 e 90) e esp?cies para o primeiro e segundo invent?rio nessa sequ?ncia, houve perda de 11 esp?cies e ganho de uma. As fam?lias mais representativas Fabaceae (15 e 14), Rubiaceae (8 e 8), Myrtaceae (7 e 5) e Bignoniaceae (7 e 7). Houve perda de duas fam?lias Siparunaceae e Opiliaceae. No entanto, na FES n?o houve mudan?as na riqueza de fam?lias (43), j? as esp?cies (132 e 129) perderam cinco e ganharam duas esp?cies. As fam?lias com mais esp?cies eram Fabaceae (21 e 20), Myrtaceae (14 e 12), Lauraceae e Meliaceae (9 e 9) e Rubiaceae (8 e 8), respectivamente. As taxas de mortalidade foram superiores as taxas de recrutamento nas tr?s fitofisionomias, no CSS (mortalidade de 2,13% ano-1 e recrutamento de 1,13% ano-1), seguindo essa mesma sequ?ncia para as outras fitofisionomias, no CD (8,84 e 1,18% ano-1) e FES (2,54 e 1,03% ano-1), respectivamente. Entre o primeiro e segundo invent?rio, houve acr?scimo de ?rea basal no somente no CSS. De maneira geral, os padr?es de din?mica foram mais acelerados nas popula??es do CD, onde visualmente os dist?rbios foram maiores, indicando que dependendo dos intervalos entre os dist?rbios, isso pode colocar em risco o estabelecimento de novos indiv?duos e o futuro das esp?cies. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / This work aimed to evaluate the floristic and structural changes at the level of community and tree populations in physiognomies of cerrado and semideciduous seasonal forest. The study area is situated on the Experimental Farm of the Moorish in Curvelo - MG (Cerrado sensu stricto ? CSS ? 18.84? S and 44.39? W; Cerrad?o ? CD ? 18? 82?S and 44? 25?? W; and semideciduous seasonal Forest ? FES - 18? 45' S and 45? 25' W, average elevation of 715 m), the climate and the type K?ppen Aw and about presence of Microaggregates substrate acidic and dystrophic. A first inventory was conducted in the CSS and CD in 2010 where they were identified, measured and estimated time, for all individuals living with (diameter 0.30 m height from the ground) (DAS) ? 5.0cm. To the FES, the first inventory occurred in 2011 and were measured diameters and identified all individuals living with diameter breast height (dbh) ? 5.0 cm. The second inventory of all physiognomies was held in 2015, and the same criteria were adopted in the previous inventory, being remeasured survivors, recorded dead and individuals who have attained the minimum diameter for inclusion in the second inventory (recruits) received plates with numbering and were identified and measured. On each plot of each phytophysiognomy, environmental variables were collected for analysis of correlation (vegetation and environment). Dynamic analyses were performed, structural and floristic most abundant populations, all species were classified as conservation status, wood density and seed dispersal. In CSS, loss of a single species Zeyheria montana. Families with more representatives Fabaceae (13 and 13), Bignoniaceae (6 and 5), Vochysiaceae (5 and 5) and Malpighiaceae (4 and 4).In the cd, accounting for families (36 and 34), genres (74 and 69) and species (100 and 90), there were 11 species loss and gain a. The most representative families fabaceae (14 and 15), rubiaceae (8 and 8), myrtaceae (7 and 5) and bignoniaceae (7 and 7). Loss of two families Siparunaceae and Opiliaceae. While in FES, don't listen to changes in family wealth (43), species (132 and 129) lost five and won two species. Families Fabaceae species (20 and 21), Myrtaceae (14 and 12), Lauraceae and Meliaceae (9 and 9) and Rubiaceae (8 and 8) respectively. Mortality rates were higher than the rates of recruitment in the three physiognomies, in CSS (2.13 and 1.13%. year-1), CD (8.84 and 1.18%. year-1) and FES (2.54 and 1.03% year-1) respectively. Mortality rates were higher than the rates of recruitment in the three physiognomies, in CSS (2.13 and 1.13%. year-1), CD (8.84 and 1.18%. year-1) and FES (2.54 and 1.03% year-1) respectively. Between the first and second inventory, there was an increase of basal area in CSS only. In General, dynamic patterns were more rapid in populations of the CD, where visually the disturbances were greater, indicating that depending on the intervals between the disturbances, it can jeopardize the establishment of new individuals and the future of the species.

No description available.

Question: Has the basal area of pine and spruce in a protected forest changed between 1937 and 2022? And has there been a change in size distribution?Location: Säby Västerksog, a pine-dominated coniferous forest protected for 100 years.Method: A part of the reserve was mapped, and diameter at breast height, using the same methods as used in 1937.Results: Basal area had increased for both pine and spruce but mostly for pine. More pine than spruce had survived from 1937. On the other hand, more spruce than pine had become established after 1937. The size distribution of pine had shifted towards larger trees, with few smaller ones. The corresponding distribution among spruce showed a decline towards larger trees (except the largest ones).Conclusion: The reason for the poor regeneration of pine is probably due to a combination of shade intolerance and a lack disturbances needed for this species (e.g. forest fires). Due to these hindrances pine is expected to decrease within a longer time frame, while spruce is expected to increase.

Tree-ring formation of eastern white-cedar (Thuja occidentalis L.) at a boreal lake in northwestern Quebec, Canada, was monitored using manual band dendrometers to (i) retrace cambial activity phases, (ii) evaluate the effects of flooding on radial growth, and (iii) analyze the relationships with meteorological factors. The daily circumferential activity of four trees at each of two sites, a riparian and an upland site, was recorded during the growing season of 1996, a year with an extreme spring flood. First cambium cell divisions occurred near June 9, followed by a distinct and sustained upward trend in the stem basal area until mid-July that reflected the earlywood formation. The strongly synchronous circumferential activity at both sites suggests no adverse flooding effect on growth of the riparian trees, which is explained by the rapid retreat of the water just before growth initiation in early June. The following month until mid-August was characterized by strong short-term fluctuations caused by alternating drought and rain periods and a slight downward trend of the basal area for six of the eight banded white-cedars. The dendrometers of two trees, the closest to the lake, showed a slight upward trend probably reflecting latewood formation. Pearson correlation with meteorological data indicated that precipitation was positively related to the daily changes in basal area of all trees except during the period of earlywood formation, which probably resulted from the high soil moisture after spring snow-melting. Mean and minimum air humidity were positively related and maximum temperature negatively related to the daily variations in stem circumference during the whole monitoring period, emphasizing the importance of the internal water status on stem size.

Landsat imagery has been used successfully to assess burn severity and monitor post-fire forest structure in a variety of ecosystems, but to date there are few documented studies on its application in the eastern deciduous forests of the eastern United States. The occurrence of a wildfire in the Daniel Boone National Forest in2010 provided a rare opportunity for research into the use of Landsat data for assessing burn severity and its ecological effects. We used differenced normalized burn ratio (∆NBR) to quantify burn severity. The ∆NBR based burn severity classification had 70% agreement with a qualitative ground-based burn severity assessment. We also examined the relationship between the presence of an invasive species (Paulownia tomentosa), and our assessment of burn severity, where we found a weak but statistically significant relationship (adj R2 0.13, p<0.0001). We also examined the relationship between the normalized difference vegetation index (NDVI) and forest structure measurements. The relationship between NDVI and basal area was strongly and significantly related (adj R2 0.41, p<0.0001). The relationship of NDVI with stem density was weak but significant (adj R2 0.23. p=0.004). These results indicate that data from Landsat imagery have great potential for quantifying burn severity, identifying potential hotspots for invasive species, and assessing post fire forest structure in the eastern deciduous forest.

The aim of the present study was to assess the productivity and growth rate of three native species (Cabralea canjerana, Cedrela fissilis and Cordia trichotoma), with supposedly productive and economic potential, in unmanaged native forest fragments of Vale Vêneto district, in São João do Polêsine, a town in the central region of the state of Rio Grande do Sul, Brazil. In 1994, 346 permanent observation plots were randomly installed by Durlo (1996) in the forests of Vale Vêneto. In these plots, there were, among other species, 146 Cabralea canjerana, 117 Cedrela fissilis and 46 Cordia trichotoma trees. The occurring species were identified around each of the selected trees; the diameter at breast height (DBH), the distance between neighboring trees (co-occurring species) and the selected ones (subject species), and basal area per hectare were measured; in addition, the site characteristics were described, and eight crown radii were measured in order to determine productivity. Between 1995 and 2003, the increments in DBH and in basal area (g), competition indices, and morphometric parameters were calculated for each of the three selected species. The model ig = f (a + b. dimension + c. competition + d. site + e. morphometry) was used to describe the increment in basal area. The dependence of increment upon competition was tested using competition indices. Easily determined site parameters were assessed around each selected tree, namely relief, slope gradient, stone cover, and cardinal direction. The morphometric parameters (crown ratio, degree of slenderness, saliency measure, range measure and crown formal measure were calculated using dimensional characteristics (DBH, total height, length, diameter, and eight crown radii). The major results show that the largest basal area increments were observed for Cedrela fissilis, Cabralea canjerana and Cordia trichotoma, respectively. However, this difference was not statistically confirmed. There was no significant difference in productivity across the analyzed species. The three species demonstrate a growing and regular basal area increment on an annual basis as their DBH increases. The inflection points of growth curves were not reached, which indicates the necessity of further research studies that include trees with larger DBH. The regression analysis allowed selecting the mathematical models that best describe the basal area increment and productivity of each species. / Este trabalho foi desenvolvido com o objetivo de se conhecer a produtividade e o ritmo de crescimento de três espécies nativas (Cabralea canjerana, Cedrela fissilis e Cordia trichotoma), as quais acreditou-se terem potencial produtivo e econômico, em fragmentos florestais nativos não-manejados do distrito de Vale Vêneto, no Município de São João do Polêsine, situado na região central do Rio Grande do Sul. No ano de 1994, foram instaladas por Durlo (1996), aleatoriamente, 346 unidades amostrais de observação permanente nas florestas de Vale Vêneto. Nessas unidades amostrais, foram encontradas, entre outras, as três espécies objeto desse estudo, respectivamente, 146 canjeranas, 117 cedros e 46 louros. No entorno de cada uma das árvores selecionadas, foram identificadas as espécies ocorrentes, medidos os diâmetros à altura do peito (DAP s), medidas as distâncias das árvores circundantes (concorrentes) até as árvores selecionadas (concorridas), determinada a área basal por hectare, caracterizados os sítios circundantes e medidos oito raios de projeção de copa para a determinação da produtividade. Para as três espécies selecionadas, individualmente, no período de 1995 a 2003, foram calculados os incrementos em DAP e em área basal (g), índices de concorrência e índices morfométricos. Para a descrição do incremento em área basal de cada uma das espécies, foi utilizado o seguinte modelo: ig = f (a + b.dimensão + c.concorrência + d.sítio + e.morfometria). A dependência do incremento em relação à concorrência foi testada por meio de índices de concorrência. Ao redor de cada árvore estudada, foram observadas variáveis definidoras de sítio de fácil determinação como o relevo, a inclinação, a pedregosidade e a exposição. Utilizando-se as características dimensionais (DAP, altura total, comprimento, diâmetro e oito raios de copa), foram calculados os índices morfométricos: proporção de copa, grau de esbeltez, índice de saliência, índice de abrangência e índice formal de copa. Os principais resultados obtidos foram os seguintes: os incrementos mais altos em área basal foram observados, respectivamente, para Cedrela fissilis, Cabralea canjerana e Cordia trichotoma. Porém, essa diferença não foi comprovada estatisticamente. Não foram encontradas diferenças significativas de produtividade entre as espécies. As espécies estudadas têm incremento periódico anual em área basal ascendente à medida que apresentam maiores DAP s. Ainda não foram atingidos os pontos de inflexão das curvas de incremento, o que induz à realização de novos estudos sobre o tema, que incluam árvores de maiores DAP s. Mediante a análise de regressão, selecionaram-se os modelos matemáticos que melhor descrevem o incremento em área basal e a produtividade de cada espécie.