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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
891

Use of Smartphone and GIS Technology for Sustainable Forestry in Eastern Ontario

Kennedy, Richard R. January 2012 (has links)
This study examined whether the current generation of consumer-grade digital mobile computing technology, so called smartphone technology, is usable to perform and improve field data collection in the context of sustainable forest management. An electronic data acquisition system, based on a handheld smartphone device and desktop geographic information system (GIS), was developed. A proprietary timber cruise application and commercial mapping software were used with the smartphone/desktop GIS to record and process forest stand and geospatial data. Usability testing was carried out to measure workflow efficiency and system performance of the smartphone GIS compared to traditional paper-based methods. The smartphone GIS successfully met performance objectives and significantly increased workflow efficiencies by improving data transfer and processing times over conventional paper methods; however, use of the mobile device resulted in greater data entry errors, increased data collection times, and led to more equipment malfunctions than use of paper recording methods together with a GPS and digital camera. Overall, the prototype electronic data acquisition system was not reliable as a stand-alone solution solely responsible for collecting cruise data, but was found to be well suited for ad-hoc mapping of forest features.
892

Analysis of biomass, biomass sampling methods, and weight scaling of lodgepole pine

Johnstone, W. D. (Wayne David) January 1967 (has links)
Tree and tree component weights of 63 forest-grown lodgepole pine trees were investigated. Data were collected from one tenth-acre plot located in south western Alberta. Both graphical and multiple regression techniques were used. Of the independent variables tested, tree basal area was most closely related to the component weights, with the exceptions of bole bark weight and total stem dry weight. The fresh and dry weights of bole bark were most closely associated with tree height, and total stem dry weight was most closely associated with dbh. Very reliable estimates of tree and tree component weights were obtained using regression techniques and the independent variables previously mentioned. The proportions of the component weights of the total tree weights were determined. The proportions were highly variable and widely dispersed about the mean. The tree characteristic most closely associated with the various proportions varied for the component being analysed. The proportion of the total tree weight contained in the stem, slash, bark and bole wood decreased with increasing tree size. The proportion represented by the needles, branches, merchantable stem, and crown increased with tree size. The crown and needle characteristics of lodgepole pine were investigated. Tree size, whether measured as stem weight in pounds or cubic foot stem volume (ob), was most closely correlated with dry needle weight (in pounds). The number of needles per cubic foot of stem volume increased with increasing tree size. The needle characteristics of lodgepole pine are highly variable. Needle length was significantly related to needle width. Needle length was not significantly related to any tree characteristics. The need to develop reliable sampling methods for biomass and fire control studies was discussed. Double sampling with regression appeared to offer accurate estimates with a minimum of weight measurement. The number of trees required to obtain a sample mean within plus or minus 10 per cent of the population mean at the 95 per cent confidence level is too large to be practical for most biomass and fire control studies. A higher standard error of estimate is probably more desirable, thus allowing a greater number of conditions to be sampled in order to increase the representativeness of the study. The mutual relationship between tree weight and tree volume was investigated. Tree volume was highly correlated with tree weight. Reliable estimates of tree weight were obtained from tree volume. Variation in moisture content and specific gravity, within and between trees was analyzed. These variables were surprisingly uniform and appear to pose only minor problems in weight scaling, for lodgepole pine. / Forestry, Faculty of / Graduate
893

Using the jackknife technique to approximate sampling error for the cruise-based lumber recovery factor

Jahraus, Karen Veronica January 1987 (has links)
Timber cruises in the interior of British Columbia are designed to meet precision requirements for estimating total net merchantable volume. The effect of this single objective design on the precision of other cruise-based estimates is not calculated. One key secondary objective, used in the stumpage appraisal of timber in the interior of the province, is estimation of the lumber recovery factor (LRF). The importance of the LRF in determining stumpage values and the fact that its precision is not presently calculated, prompted this study. Since the LRF is a complicated statistic obtained from a complex sampling design, standard methods of variance calculation cannot be applied. Therefore, the jackknife procedure, a replication technique for approximating variance, was used to determine the sampling error for LRF. In the four cruises examined, the sampling error for LRF ranged from 1.27 fbm/m³ to 15.42 fbm/m³. The variability in the LRF was related to the number of sample trees used in its estimation. The impact of variations in the LRF on the appraised stumpage rate was influenced by the lumber selling price, the profit and risk ratio and the chip value used in the appraisal calculations. In the cruises investigated, the change in the stumpage rate per unit change in the LRF ranged between $0.17/m³ and $0.21/m³. As a result, sampling error in LRF can have a significant impact on assessed stumpage rates. Non-sampling error is also a major error source associated with LRF, but until procedural changes occur, control of sampling error is the only available means of increasing the precision of the LRF estimate. Consequently, it is recommended that the cruise design objectives be modified to include a maximum allowable level of sampling error for the LRF. / Forestry, Faculty of / Graduate
894

Computer image based scaling of logs

Finnighan, Grant Adam January 1987 (has links)
Individual log scaling for the forest industry is a time consuming operation. Presented here are the design and prototype test results of an automated technique that will improve on the current speed of this operation, while still achieving the required accuracy. This is based on a technique that uses a television camera and graphics monitor to enable the operator to spot logs in images, which an attached processor can automatically scale. The system must be first calibrated however. Additional to the time savings are the advantages that the accuracy will be maintained, if not improved, and the operation may now be performed from a sheltered location. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
895

The sociocultural importance of fur trapping in six northeastern states

Daigle, John Joseph 01 January 1997 (has links)
Social, economic, and cultural components of trapping furbearers was studied in six Northeast states. In 1994, a 12 page mail-back questionnaire was sent to a sample of licensed trappers in Maine, Massachusetts, New York, Pennsylvania, Vermont, and West Virginia. A total of 2,279 questionnaires was returned for an overall response rate of 65 percent for the six states combined. Factor analysis identified five underlying dimensions associated with the importance of reasons for trapping. The strongest reasons related to dimensions associated with "Lifestyle Orientation," and "Nature Appreciation," followed by "Wildlife Management." Other reasons related to "Affiliation with Other People," and "Self Sufficiency," though they did not rank as high in importance for the overall sample as did the previous three dimensions. To identify the existence, structure, and function of trapping-related networks of trappers, 92 fur trappers from the six states participated in face-to-face, in-depth interviews designed to gather data on their trapping-related social relationships and interactions. Participation in trapping-associated activities included cooperatively setting and checking traps; processing pelts; verbally sharing trapping experiences with others; giving, bartering, or selling pelts, products, meat, and trapping services; and participating in events such as a fur auction or rendezvous. These forms of interaction linked trappers to broader social network structures that included nuclear family, extended family, friends, workmates, neighbors, landowners, wildlife agency personnel, trapping association members, and fur buyers. Overall, respondents who trapped alone, primary alone, or with others, exhibited similar patterns of trapping-related ties and interactions with other people. These patterns included a high level of trapping-related interactions with nuclear family members, friends, participants at trapping association events, and fur buyers; and a moderate level of interaction with extended family, landowners, and wildlife agency personnel. Far fewer trappers reported trapping-related interactions with workmates and neighbors. Findings indicate women trappers exhibited much less of a tendency than men to have trapping-related ties with friends or with fur buyers. Results suggest network relationships act as 'social resources' that not only facilitate affective ties of sociability and companionship but also serve instrumental purposes such as sharing of information, social support, and exchanges of furbearer-related goods and services.
896

Armillaria in Massachusetts forests: Ecology, species distribution, and population structure, with an emphasis on mixed oak forests

Brazee, Nicholas Justin 01 January 2011 (has links)
The ecology, species distribution, and population structure of Armillaria was investigated in the forests of Massachusetts. From 64 plots at 16 sites, 640 isolates of Armillaria were collected from six forest types (northern hardwoods, mixed oak, pitch pine, white pine, white pine/mixed oak, and eastern hemlock). Armillaria gallica proved to be the most abundant species, making up 316/640 (52%) of all isolations. This was followed by A. solidipes (219/640; 34%), A. mellea (46/640; 7%), A. calvescens (36/640; 6%), A. gemina (16/640; 3%), and A. sinapina (7/640; 1%). Armillaria gallica was routinely encountered causing significant decay of the lower bole on living hardwood hosts, especially oaks. The population structure of 153 isolates of A. gallica collected from mixed oak forests was investigated using amplified fragment length polymorphisms (AFLPs). From a total sampling area of 4.51 ha, 38 AFLP genotypes were discovered, yielding a figure of eight genets per hectare with the average A. gallica genet occupying 0.13 ha. When the effects of hydrolyzable tannins on in vitro growth were compared between A. calvescens and A. gallica, it was A. gallica that appeared better at oxidizing and metabolizing commercial tannins (tannic acid and gallic acid) along with black oak root bark extracts. This was determined through measurements of colony area and dry biomass, and suggests that A. gallica may be a better adapted pathogen of oak. In order to more accurately distinguish between isolates of A. calvescens and A. gallica, a three-gene phylogeny was reconstructed, using partial sequences of the elongation factor 1-alpha (tef1), RNA polymerase II (rpb2) and nuclear large subunit (nLSU) genes. After comparing 12 isolates each of A. calvescens and A. gallica that originated from across northeastern North America, only the tef1 gene could accurately distinguish these two species. Five single nucleotide polymorphisms were present between the two species and maximum likelihood and maximum parsimony methods grouped A. calvescens and A. gallica into monophyletic clades.
897

Current real estate development industry usage of sustainable forestry products in the Southeast

January 2012 (has links)
0 / SPK / specialcollections@tulane.edu
898

The influence of experimental Trichinella pseudospiralis infections on the reproduction and behaviour of captive American kestrels (Falco sparverius) /

Saumier, Michèle Dominique January 1986 (has links)
No description available.
899

Etude des endoparasites et plus spécialement du ver des méninges (Parelaphostrongylus tenuis) du cerf de Virginie (Odocoileus virginianus borealis) à l'ile d'Anticosti

Beaulieu-Goudreault, Michelle. January 1981 (has links)
No description available.
900

Forest ecological studies in the northern conifer hardwood region of Central Southern Ontario.

Davies, Bryan W. January 1968 (has links)
No description available.

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