Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 109 for “"hardwoods"”.
-
Modeling Solvent Extraction of Lignin from Hardwoods
… behavior of solvent extraction of lignin from hardwoods by adapting the framework of the FLASHCHAIN theory (Niksa and Kerstein, 1991; Niksa, 2017). A constitution submodel specifies distributions of molecular weight and reactive sites for native lignin. The model simulates delignification as …
-
Long-term dynamics of forest phenology across the central hardwoods
… Many forest communities across the central hardwoods region of the United States are experiencing shifts from oak dominance to later successional species after anthropogenic alterations to historical disturbance regimes. This transition, amidst unprecedented climatic variability, casts …
-
The marketing of lesser known tropical hardwoods in the U.K
The present study set out to identify and analyse the relative importance of the various factors which affect the acceptance of lesser-known Tropical Hardwood species. Two different groups of factors were analysed, physical/technical factors and marketing factors, emphasis was placed on the second …
-
A stand level multi-species growth model for Appalachian hardwoods
… of thinned stands of mixed Appalachian hardwoods. The model allows prediction by species groups and diameter classes. Stand attributes ( basal area per acre, trees per acre, minimum stand diameter, and arithmetic mean dbh) were projected through time for the whole stand and for …
-
Using economic factors in managing Appalachian hardwoods for high quality
Because of the extremely wide range in product values from hardwood stands, harvest decisions must consider a multiplicity of factors, many of them economic. Among these are species, tree size, tree quality, logging costs, and market alternatives. This study demonstrates how to incorporate these, …
-
An Evaluation of Concepts and Tools for Managing the Northern Hardwoods
Across the northern hardwoods of North America, there is considerable variation at the stand level (e.g. species composition, stocking, and growth) as well as among individual trees (e.g. stem quality, value, and growth). This variation challenges the management of the northern hardwoods by …
-
Development of a method for implementing group selection in Appalachian hardwoods
… group selection regeneration in Appalachian hardwoods. The diverse set of definitions of the method, and the current forest demands are combined to form a flexible system of implementation that can accommodate public as well as private forests. Group selection is used where an uneven-aged …
-
Changes in stand structure and species diversity following clearcutting in central Appalachian hardwoods
The clearcutting of second-growth Appalachian hardwood forests may cause a reduction in species diversity of the new cohort. This study measured changes in species composition, diversity, and stand structural characteristics following clearcutting of a second-growth hardwood forest. To evaluate the …
-
Evaluation of Topsoil Substitutes for Restoration of Appalachian Hardwoods on Strip Mined Land
Current surface mine reclamation in Appalachia involves returning the land to approximate original contour by grading the surface and planting grasses and early-successional trees. This results in a greatly altered ecosystem compared to the native forest that was there prior to mining. The …
-
Fire and non-native grass invasion across a heterogeneous landscape in the Central Hardwoods
Non-native grass invasions have the potential to change natural and prescribed fire regimes by altering fuels, which in turn may promote further invasion. I examined if invasion by Microstegium vimineum, a non-native annual grass resulted in a positive invasion-fire feedback in eastern deciduous …
-
Analysis of Southern Hardwoods as Furnish for a Wood Flake-Resin Composite Structural Material
Made available in DSpace on 2014-12-12T00:25:58Z (GMT). No. of bitstreams: 1 7511860.pdf: 5306181 bytes, checksum: 293fae4746b6e600238becdc104229c4 (MD5) Previous issue date: 1974
-
Influences of varying stand harvest methods on timber harvesting costs in southwestern Virginia hardwoods
A method was developed for estimating costs of harvesting operations in the hardwood stands of the Appalachian region of southwestern Virginia. The method was then tested on one logging operation to estimate the cost of harvesting a group selection tract as compared to a clearcut. Eight loggers …
-
Sensitivity Analysis of the Forest Vegetation Simulator Southern Variant (FVS-Sn)for Southern Appalachian Hardwoods
The FVS-Sn model was developed by the USDA Forest Service to project and report forest growth and yield predictions for the Southern United States. It is able to project forest growth and yield for different forest types and management prescriptions, but it is a relatively new, complex, and …
-
Factors limiting the regeneration of large-seeded hardwoods in the Upper Coastal Plain of South Carolina
… factors limiting regeneration of large-seeded hardwoods in the Upper Coastal Plain of South Carolina, we planted one-year old bare root Quercus alba L. and Cornus florida L. seedlings in pine plantation understories and adjacent clearcuts. We hypothesized that soil moisture, light, and leaf and …
-
Assessment of silvicultural practices to improve survival and growth of pioneer and mid-successional hardwoods on old field restoration sites
Survival and growth of planted trees are common indices used to evaluate success of wetland restoration efforts used to compensate for wetland losses. Restoration efforts on marginal agricultural lands typically result in less than satisfactory survival and growth of desired tree species. This …
-
Modeling the impact of gypsy moth defoliation in individual tree mortality and basal area growth of northern hardwoods of central Pennsylvania
Data for this study were collected by the US Forest Service and the Pennsylvania Bureau of Forestry on nearly 600 plots in central Pennsylvania. Tree and stand characteristics recorded between 1978 and 1985 include estimates of percent defoliation on individual trees. Logistic regression using …
-
Competitive status of red spruce (Picea rubens) and Fraser fir (Abies fraseri) at ecotonal transitions in southern Appalachian sky islands
… spruce-dominated stands at middle elevations and hardwoods associating at lower elevations. A primary concern is encroachment of hardwoods upslope as climate change-driven milder temperatures and high precipitation confine spruce-fir forests to even higher elevations. We performed a …
Page 1 of 6