Canadian forest tenures serve as policy tools which have important economic implications. This study analyzes the effect of some British Columbia forest tenures on the distribution of economic rents, the allocation of resources, and silvicultural investments. The thesis first identifies the problem governments face, as landlords, in attempting to specify an optimum tenure. Tenures may be described in terms of packages of individual characteristics, each of which may be controlled, to varying degrees, by governments. The problem governments face is choosing an optimal combination of specified characteristics. Several problems emerge in the specification of individual tenure characteristics and their aggregation into whole optimum tenures. The specification of any one optimum tenure characteristic requires political value judgments implicit in social welfare functions. Furthermore, interdependencies exist between tenure characteristics which make difficult the aggregation of optimally specified characteristics into an optimum tenure. The interdependencies between tenure characteristics provide the basis for two hypotheses. First, every tenure characteristic may influence the benefits of tenure holders. Second, tenure holders may expect their tenures to change, which may influence the future benefits that they receive. By testing these hypotheses, the effect of tenures on the distribution of rents and allocation of resources are analyzed. To test these hypotheses, tenure holders in British Columbia were interviewed to obtain empirical measurements of the effects of attenuations of tenure characteristics on benefits of tenure holders, and the security tenure holders perceive in their tenures. Results support both hypotheses and show how tenures are distributing rents and allocating resources. The study also investigates the effects of tenures on investments in silviculture. Tenure holders in British Columbia are surveyed to determine amounts spent on silviculture on selected tenure types. It is found that tenure holders which have incentives for voluntary investments in silviculture spend significantly greater amounts than those who make expenditures which are reimbursed or mandatory. Using the results of this study, recent changes in British Columbia forest policy are critiqued and areas for further research are identified. / Forestry, Faculty of / Graduate

A serial multi-resolution stereo matching algorithm is presented that is based on the Marr-Poggio matcher (Marr and Poggio, 1979). It is shown that the Marr-Poggio feature disambiguation and in-range/out-of-range mechanisms are unreliable for non-constant disparity functions. It is proposed that a disparity function estimate reconstructed from the disparity samples at the lower resolution levels be used to disambiguate possible matches at the high resolutions. Also presented is a disparity scanning algorithm with a similar control structure, which is based on an algorithm recently proposed by Grimson (1985). It is seen that the proposed algorithms will function reliably only if the disparity measurements are accurate and if the reconstruction process is accurate. The various sources of errors in the matching are analyzed in detail. Witkin's (Witkin, 1983) scale space is used as an analytic tool for describing a hitherto unreported form of disparity error, that caused by spatial filtering of the images with non-constant disparity functions. The reconstruction process is analyzed in detail. Current methods for performing the reconstruction are reviewed. A new method for reconstructing functions from arbitrarily distributed samples based on applying coordinate transformations to the sampled function is presented. The error due to the reconstruction process is analyzed, and a general formula for the error as a function of the function spectra, sample distribution and reconstruction filter impulse response is derived. Experimental studies are presented which show how the matching algorithms perform with surfaces of varying bandwidths, and with additive image noise. It is proposed that matching of scale space feature maps can eliminate many of the problems that the Marr-Poggio type of matchers have. A method for matching scale space maps which operates in the domain of linear disparity functions is presented. This algorithm is used to experimentally verify the effect of spatial filtering on the disparity measurements for non-constant disparity functions. It is shown that measurements can be made on the binocular scale space maps that give an independent estimate of the disparity gradient this leads to the concept of binocular diffrequency. It is shown that the diffrequency measurements are not affected by the spatial filtering effect for linear disparities. Experiments are described which show that the disparity gradient can be obtained by diffrequency measurement. An industrial application for stereo vision is described. The application is automated measurement of logs, or log scaling. A moment based method for estimating the log volume from the segmented two dimensional disparity map of the log scene is described. Experiments are described which indicate that log volumes can be estimated to within 10%. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

The currently topical problems of forest management are issues of trans-science. They can be framed in the language of science but they cannot be resolved in the language of science. They involve historically contingent phenomena for which predictive certainty is not possible and they involve issues of moral, aesthetic and economic value. What is the role of science in contributing to the public debate on what are fundamentally social issues such as clear-cut logging or the preservation of old-growth forests? A history and philosophy of science, in general, and ecological science, in particular, is presented that traces the transition, over the last half century, from a positivist science of universal, timeless, predictable order to a science that attempts to interpret local, particular aspects of nature. The former relies on identifying restricted spatio-temporal scales that facilitate prediction while the latter focuses on an understanding of the causal relations within interrelated systems that facilitate explanation of system properties. A kind of contextual or dialectical holism is advocated wherein system components are considered in the context of the whole and the whole is considered as an epiphenomenon resulting from causal interaction of the parts. A history of forest science is presented that identifies sustained yield forestry as a construct of positivist science. Recent insights by ecological science, into the complexity and contingency of forest ecosystems, reveal the limitations of this simplified view. Moreover, the application of a single large-scale strategy such as sustained yield forestry to managing forests in British Columbia contained value assumptions that no longer reflect the full range of values that the public express. The currently topical debates on clear-cutting, logging in municipal watersheds and over-cutting are offered as examples of how questions of fact and questions of value become linked. Although these debates have been carried on in the language of science they are essentially social issues and cannot be resolved by science. The role of science in contributing to the resolution of social issues, such as the development of a sustainable forestry, is not to develop specific solutions but to contribute to the social dialogue in a subservient fashion. Science can characterize the context in which disagreements about matters of value take place. Science can use its experimental protocols to help society construct living experiments that allow us to learn our way into the future. Science can take part in an equitable conversation on sustainable forestry that will facilitate a better understanding of the beliefs and values of the human component of forested ecosystems. / Graduate and Postdoctoral Studies / Graduate

Having made the fundamental assumption that policy administration can be viewed as a process the question is then raised: In what ways and to what extent does the administrative process affect forest resource use policies in British Columbia? It is noted that the three basic policy principles have been since early this century: (i) public ownership of forest lands; (ii) a return to the Provincial Treasury of a proportion of the wealth of the forests as it accrues; and, (iii) extension of the useful life of the forests for the benefit of future generations. Using as a principle data source a large body of statutes, administrative documents and evidence and reports of commissions of inquiry accumulated during the past seventy-five years the thesis focuses on the administrative process with respect to three major aspects of forest resource policies in British Columbia. They are: land tenure systems, sustained-yield management of forest areas and royalty and stumpage assessment methods. The research confirms the validity of the basic assumption. In response to the above question several major points are made. Provincial land ownership policies and their administration have been significant in directing forest resource use administration and have had the affect of obscuring forest resource use policy principles themselves. With respect to the sustained-yield management programme in British Columbia the administrative process has affected forest resource use policies by giving administrative definitions to some of the basic terms used in the initial policy formulations. In the area of royalty and stumpage assessments methods it was found that administrative feasibility, which has been especially influenced by forest technology, has been a significant factor in determining the ends actually pursued by the administrative system and thus formally stated policy objectives have been modified. Overall the affect of the administrative process on forest resource use policies in British Columbia has been widespread and far reaching. / Arts, Faculty of / Political Science, Department of / Graduate

This thesis is concerned with questions relating to the optimal regulation of logging in a solely owned forest. Optimal is taken to mean maximizing the present value of net revenues obtainable from growing and harvesting an infinite sequence of crops on a piece of forest land. Discussions of optimal harvesting usually assume there is no advantage to changing the age distribution of a forest. This is also the assumption of Chapter I. In this case, trees are cut when their age reaches the rotation period which is determined from what is called the Faustmann formula. Chapter I looks at the comparative statics of these rotation periods. The effect of a change in an exogenous parameter on the rotation period is shown to depend on how certain elasticities are changed. It is then shown that there are conditions under which these results extend to a more complex forestry model where the manager chooses the level of effort to be expended on regeneration and silvicultural activities. The techniques used are drawn from optimal control theory. Chapter II introduces considerations which may make it advantageous to alter the age structure of a forest while logging it. In particular, a variable average cost of harvesting function is allowed for. A forestry maximum principle is derived which determines the dynamics of optimal harvesting. This is similar to the maximum principle for processes incorporating a delay (the time between planting and harvesting). The usual growth theory questions are then asked. In the variable average cost case, the "steady state" age distributions turn out to be "normal" forests with the time between harvests being determined by a Faustmann formula Global asymptotic stability is not proven but is shown to be likely. Finally, Chapter III applies the forestry maximum principle to a problem of determining an optimal harvesting policy for a group of forests subject to a sustained yield constraint. Assuming stability and with a few additional restrictions, it is shown that the optimal long run policy is to convert each separate forest to a "normal" forest. The Faustmann formula determines the number of age classes in each forest. / Arts, Faculty of / Vancouver School of Economics / Graduate

The author developed a statistical procedure to analyze irregular, unbalanced inventory data by the least squares principle. The method is found useful in forestry where data collected are often unbalanced in nature. It provides a unique means to incorporate qualitative as well as quantitative variables in forest yield analyses. Inventory data for three major species — Douglas-fir, spruce, and lodgepole pine were analyzed in connection with the study of growth and yield of pure (81% or more of the overstory is of a single species) and mixed stands in up to 12 B.C. forest inventory zones in which they occurred. More than 50% of Douglas-fir, spruce, and lodgepole pine stands occur naturally in pure stands. If there are any adverse effects on the establishment of pure stands, these should have been well reflected quantitatively in the data provided by the B.C. Forest Service. Estimates of site index from the inventory data might support that pure stands deteriorate soil conditions; however, the higher site indices in mixed stands may be attributed to the better site conditions when the stands were originally established. Mixed conifer stands tend to grow more trees per acre than pure or hardwood mixed type stands. Among the three species investigated, Douglas-fir required more growing space than the others. The relative stand density based on basal area per acre also indicates that stand density is higher in conifer mixed stands than in pure or hardwood mixed type stands. The mean annual increment is higher in hardwood mixed stands than in pure or conifer mixed ones. But stand age in hardwood mixed types is much less. The mean annual basal area increment of conifer mixed stands is consistently higher than that of the other two types. Zonal variations in the mean annual basal area growth are apparent. The mean annual volume increment follows a trend similar to that of the mean annual basal area increment. Douglas-fir stands growing on the Coast and in the Interior were compared. Mean annual volume growth is 84.00 cubic feet per acre for the Coast stands and 25.53 cubic feet for the Interior stands. The effect of species composition on net volume yield is significant in Interior Douglas-fir stands, but non-significant in Coast Douglas-fir, Interior spruce, and Interior lodgepole pine stands. That the effect of forest inventory zones is highly significant in the Interior Douglas-fir, spruce, and lodgepole pine stands justifies the zonation unless adjustments are made for stand density. Interactions for types and zones are significant in the Coast Douglas-fir, the Interior spruce, and the Interior lodgepole pine stands but are nonsignificant in the Interior Douglas-fir stands. The difference in yield in the Interior Douglas-fir stands is attributable to species composition types and forest inventory zones alone. The establishment of Douglas-fir conifer mixed type stands in the Interior effectively increases forest productivity by 21%. Interpretations of the interactions lead to the conclusion that the advantages of monocultural or multicultural practices cannot be over-generalized. Pure type stands are more productive in some zones but less in the others. The same is true for multicultural practices. Growth of forest trees is essentially site-dependent. Before a decision is reached on what species composition type to establish,, foresters should carefully investigate the local site quality and past yield history of various forest types to ensure that the maximum potential productivity of a particular site can be realized. Further analyses to test the hypothesis that no differences in volume yield exist among three species composition types for stands growing on same site conditions reveal that the effects for species types and inventory zones as well as interactions thereof are not significant for Coast Douglas-fir, however, for Interior Douglas-fir stands, the effect of species composition is significant. It is shown that on similar site conditions, Douglas-fir conifer mixed stands yield substantially more than pure or hardwood mixed stands in the Interior. The species composition effect is not significant in Interior spruce stands while zonal effects and interactions for types and zones are significant. In Interior lodgepole pine stands, effects of composition types, zones, and interactions thereof differ significantly. In all three species groups investigated, that the effects of hardwood mixed type consistently shows negative 'values implies that hardwood mixed type stands are the least desirable stand composition structure for these species in the Interior. Differences in volume between pure and mixed type stands result primarily from the inequality in basal area per acre. The variables, height x basal area and basal area are most important in yield table analyses. In addition, stand age, relative basal area, and forest inventory zone are all highly significant in contributing to the variations in volume yield of the Coast Douglas-fir stands. For Interior Douglas-fir, the most significant variables are, in addition to the above two variables, stand age, and relative stand density. Effects of species composition type and forest inventory zones are non-significant. For Interior spruce, the prominent variables in yield table analysis are height x basal area, basal area, species composition, stand age, height, and relative stand density. All variables being equal, pure spruce stands outyield stands of mixed spruce-hardwood and mixed spruce-conifer. The results provide good evidence that establishment of pure spruce stands is more desirable than of spruce and conifers or hardwood mixed stands. For lodgepole pine, the most significant variables in yield tables analysis are height x basal area, species composition types, and forest inventory zones. The high significance of zonal effects suggests that a separate yield table for lodgepole pine in each zone is warranted, unless appropriate adjustments are made for site index and stand density. Yield of pure lodgepole pine stands exceeds those of lodgepole pine conifer mixed type and lodgepole pine hardwood mixed types. Therefore, for high yields the establishment of pure lodgepole pine type stands is preferred. Application of these methods to the temporary sample plot data has clearly demonstrated the widespread distribution of pure stands and lack of substantial effects of monocultures on yield. Nevertheless, the fact that higher yields may result from some multicultures should encourage establishment of long term studies of spacing and mixtures of species. / Forestry, Faculty of / Graduate

Ongoing deforestation is a pressing, global environmental issue with direct impacts on climate change, carbon emissions, and biodiversity. There is an intuitive link between economic development and overexploitation of natural resources including forests, but this relationship has proven difficult to establish empirically due to both inadequate data and convoluting geo-climactic factors. In this analysis, we use satellite data on forest cover along national borders in order to study the determinants of deforestation differences across countries. Controlling for trans-border geo-climactic differences, we find that income per capita is the most robust determinant of differences in cross-border forest cover. We show that the marginal effect of per capita income growth on forest cover is strongest at the earliest stages of economic development, and weakens in more advanced economies, presenting some of the strongest evidence to date for the existence of at least half of an environmental Kuznets curve for deforestation.

In order to identify and quantify sources of digitizing error, and to understand how error is carried through a map overlay, three experiments were performed. First, four operators repeatedly digitized eight randomly distributed points eight times. Data were analyzed using parametric statistics and by an error models so that average point digitizing error, the operator error (random error and bias), and the machine error (random error) were estimated; the operators' digitizing characteristics were statistically analyzed. In the second experiment I designed and created a standard coverage with the ARC/INFO GENERATE command. The coverage consists of a set of special geometric entities: a series of differently sized circles, differently shaped triangles and rectangles drawn by PC ARCPLOT. These figures were designed to test the effect of the original map polygons' characteristics on both machine error and operator error, such as area and perimeter, figure shape and geometric entities combination, line curvature, number of vertices selected for representing a line, position of a geometric entity on digitizing board. Several operators repeatedly digitized the coverage six or more times. The operator error (area error and perimeter error) were obtained by subtracting the standard coverage from a digitized coverage. The machine error (area error and perimeter error) were obtained by subtracting the theoretical true coverage from the standard coverage. The results were analyzed statistically. The causation of errors and the operators' digitizing characteristics were further discussed. The third experiment addressed how digitizing errors are propagated through map overlay. In this experiment the digitized coverages created in the second experiment by each operator were overlaid with the ARC/INFO UNION command. Area error, perimeter error, and the numbers of the spurious polygons were collected. The means, sums, maximum, minimum, and standard deviation of area error and perimeter error were obtained. The relationship between area error, perimeter error, and number of spurious polygons of the overlaid coverage were analyzed. This study: (1) focuses on position, as opposed to attribute, error; (2) examines errors in vector-based, not raster-based, GIS; and (3) examines errors caused during the digitizing process, and their propagation through map overlay. The digitizing method is point mode, not stream mode. Results were applied to error management and error reduction to: (1) create a theoretical model which can be used to check quality of the vector source coverages, and to lead users to correctly utilize the GIS data, to prevent them from making unnecessary mistakes; (2) identify some rules to properly use the ARC/INFO ELIMINATE command, and to set MMU (minimum mapping unit) for a particular project.

Conservation and management of marine mammal populations requires information on direct and indirect affects of anthropogenic activities, population dynamics, habitat requirements and behavioral ecology. For most populations, particularly the non-hunted smaller whales and dolphins, programs designed to collect these data are relatively new (i.e., two decades old or less). This study utilizes data collected from several recent research programs to address some specific scientific and management issues. Pilot whale by-catch relative to distant-water fleet Atlantic mackerel fishing operations was examined. Although incidental mortality was not correlated to mackerel catch and effort statistics, it was associated with fishing season and depth. By-catch is highest during spring in shelf edge waters when mackerel, fishing activity, and pilot whales are concentrated along a linear habitat. Further, pilot whale behavior in the vicinity of fishing trawlers is an important component of the by-catch problem. Seasonal and spatial overlap patterns between selected cetaceans and prey resources off the northeast U.S. indicate trophic relationships are likely broader than previously hypothesized. The degree of overlap suggests that cetacean trophic requirements are likely buffeted from stock collapse of one or more prey species. However, broad scale correlations were not observed between most cetaceans and prey spatial and temporal abundance data. A dynamic patch model incorporating energetic requirements, probability of mortality "by-catch" and finding food, food value, and habitat type was used to simulate the behavioral ecology of a hypothetical pilot whale in mid-Atlantic shelf edge waters. The model suggested that the forager will make risky decisions at low state (i.e., fat reserves) levels. The general trend was to select the safer patches at high state levels. Reducing food gain versus increasing mortality or travel costs produced the most variability in model results. This variability provides some insight into pilot whale foraging around fishing vessels, since it is assumed that, although the risk of mortality is higher, the energetic costs are lower.

The tachinid fly Compsilura concinnata (Meigen) was introduced to North America in 1906 for the biocontrol of the forest defoliators Lymantria dispar (L.) and Euproctis chrysorrhea (L.) when these caterpillars were defoliating large areas of eastern Massachusetts. Most of the flies released, however, were the progeny of adults emerging from E. chrysorrhea caterpiliars collected in Eastern Europe. Although this tachinid is a generalist parasitoid, in Europe it is considered an important specialist of pestiferous species based on the level of its recovery there. Also, as one of the first insects established against forest defoliators in the Northeast, C. concinnata is in a premier position of providing information about colonization that increases the understanding in population genetics of how founder effects and dispersal influence the establishment of exotic insect populations. Initially in this study, a historical analysis was conducted to prepare a chronology of release of C. concinnata into North America and delimit its distribution. The introduction and release of C. concinnata was relatively restricted as they were primarily reared from one host E. chrysorrhea collected in Eastern Europe. More importantly, the extent to which this fly moved ahead of successive releases suggested there may be a historical basis to expect little differentiation among their nearctic populations. The literature on population genetics and use of electrophoretic analyses were surveyed to establish their use with C. concinnata in North America. Enzyme electrophoresis has been widely used for delimiting populations of non-native parasitoids and tracking their movement into new hosts and localities. To determine the suitability of enzyme electrophoresis for a population genetic analysis of C. concinnata, selected isozymes were identified and cataloged in an established laboratory strain. The analysis of isoenzyme patterns for measuring the relatedness among and between individuals, is useful in molecular studies of population genetics provided these patterns are heritable. To determine the heritablility of isozymes in C. concinnata, an electrophoretic analysis was conducted using both the parents and adult progeny of observed matings. The genetics of some C. concinnata isoenzymes followed simple patterns of Mendlian inheritance and were allozymic. The population genetic structure of C. concinnata in North America was examined with trap-hosts placed throughout the Northeast. The flies reared out were sampled with protein electrophoresis. There were slight differences in the allozymes and allele frequencies of C. concinnata and in comparison with other Diptera, the variation among Northeastern populations was relatively low. The variability among Northeastern populations of this parasitoid reflect limited genotypes in the founding populations. Over time new differences in protein loci between geographically separated populations probably arise through selection or drift than through non-lethal mutations. The time needed for protein coding loci between distantly spaced populations of introduced insects to diverge sufficiently for them to be detectable has not been determined. Estimating the time needed for allozymes of introduced insects to reject such differentiation is useful in understanding the evolution of biotypes, but is not a trivial process. Historical research in combination with analyses of the variability in allele frequencies among populations can be useful in determining the extent of divergence in non-native species that may lead toward new biologically adapted forms.