In attempting to determine the background to the controversial term "multiple use," it was deemed necessary to briefly examine preceding social behaviour and legislation. A brief study of early European agricultural practices, through to the Industrial Revolution, allows an insight into the rural background of the early immigrants to North America. The Conservation Movement of the early 1900s was a result of socially unacceptable exploitation of natural resources and dissatisfaction with the American governments' methods of land disposal in the name of "progress." The rapid demise of the Movement is attributed to its failure to produce practical guidelines for resource management. Subsequent resource development in North America has been fragmentary; a major cause of inefficiency and a disregard for social implications. The definition of "multiple use" that appeared in the 1960 Act, like the principles of the Conservation Movement, relied on platitudes rather than practicalities. The goals of multiple use are examined, and a new definition is proposed, as is the substitution of "integrated resource management" for the shibboleth of "multiple use." The history of the development of Canada's resources parallels that of the United States. Yet because of the smallness of the population in relation to the size of the country, the exhaustibility of natural resources has been barely contemplated. Serious public concern for the manner in which Canadian resources are being managed is only of recent occurrence. The responsibility for integrated resource management lies with provincial governments. Except for the United States Forest Service, the case studies conclusively show that the biggest obstacles to the implementation of integrated resource management, are of a political nature. Some techniques of economics that pertain to the allocation and distribution of wealth generated by natural resources are examined. While none of these are entirely satisfactory, Benefit-Cost Analysis is proposed as a possible first step toward better control of resource development. In including man and his social structures within its deliberations, the discipline of ecology gains sounder foundations for analyzing the effects of resource management on society. The application of systems analysis to such complex ecological problems has great potential in allowing management strategies to be explored before being implemented. A hypothetical model is developed in which systems analysis is used to effect integrated resource management. Such a form of management presently remains as an ideal because of existing governmental, and industrial relations. Since voluntary cooperation for the public welfare appears unlikely in the near future, research will be needed to determine at which level of government to establish a department, whose function will be that of integrating resource management. / Forestry, Faculty of / Graduate

This thesis describes an optimization model for the allocation of logs from alternative sources for a series of successive time periods. The model was formulated as a multi-stage decision process and is solved by dynamic programming. The analytic framework consists of two connected recurrence equations, each incorporating two decision-variables. These two relationships, together with the feasibility regions defined for a hypothetical problem, describe the optimization process. The hypothetical allocation problem, used as a vehicle for model development, requires mill demands for quantities of pulplogs and sawlogs to be satisfied for three time periods. Logs are delivered from five available sources, four log-producing areas and an open log market, and temporary log surpluses are allowed. Only a limited quantity of logs is available from each source in each period, two of the four forest areas supply only pulplogs and a third area is inaccessible in one period. The variable unit costs of delivered logs differ not only between each source and period but are also dependent upon the magnitude of an allocation. In addition to satisfying mill demands for specified quantities of logs, there is a further requirement with regard to sawlogs. Average lumber prices are assumed to be dependent upon the tree species processed and variable log conversion costs are assumed to decrease with increase in log diameter. Consequently, the comparison of alternative allocation policies involves not only the sum of the variable delivered log costs but also a measure of the value of delivered sawlogs. In the thesis "sawlog net worth" is evaluated and combined with log production and log transportation costs to give a composite cost term, "net delivered log cost." This is the measure used to evaluate each allocation and is incorporated in the first of the two recurrence equations. This equation is used to derive minimum cost allocation policies for all possible quantities that may be allocated from each period. In the second equation the minimum costs derived from the first allocation process are combined with a second term to evaluate alternative allocations between periods. This second cost component is incurred when surplus logs are "cold-decked" for subsequent mill conversion. To ensure a sufficient flow of logs, and to take advantage of seasonal differences in "net delivered log costs," log surpluses are permitted. When log surpluses are "cold-decked" additional log handling costs are incurred which must be considered when alternative allocations between periods are evaluated. This requirement is satisfied by introducing the additional cost component into the second equation. The different derivations given for the "net delivered log costs" for five sources of logs demonstrate an important feature of the formulation: there is no requirement that costs must be linearly related to the quantity allocated. This freedom is well illustrated by the introduction of additional "fixed" costs which are dependent upon the magnitudes of the quantities allocated. In a demonstration of the flexibility of the formulation a complex log production system was assumed for source two. For each allocation from this source two optimal quantities were derived. The first was the quantity of sawlogs selected from specified log classes, the second was the optimal portion of the quantity of peeler logs developed that should be traded. An exchange could be made either for sawlogs, or for pulplogs, or both. With the development of this log allocation model a fresh approach to log production planning is now possible. The analytic framework is capable of extensive adaptation and the model itself can be readily modified to suit a variety of conditions. Whether used as described, or as part of a larger analytical system, the computational advantages of dynamic programming are now available to the planner. / Forestry, Faculty of / Graduate

Weigh scaling is a method of estimating the total volume of timber harvested from a given region. The implementation of statistical sampling techniques in weigh scaling is described, along with related issues. A review of ratio estimators, along with variance estimators of the classical ratio estimator is conducted. The estimation of the variance of the estimated total volume is considered using jackknife- and bootstrap-based variance estimators. Weighted versions of the jackknife and bootstrap variance estimators are derived using influence functions and Fisher Information matrices. Empirical studies of analytic and resampling-based variance estimators are conducted, with particular emphasis on small sample properties and on robustness with respect to both the homoscedastic variance and zero-intercept population characteristics. With a squared error loss function, the resampling-based variance estimators are shown to perform very well at all sample sizes in finite populations with normally distributed errors. These estimators are found to have small negative biases for small sample sizes and to be robust with respect to heteroscedasticity. / Science, Faculty of / Statistics, Department of / Graduate

The forest floors of three biogeocoenoses, from northern Vancouver Island, were stratified into LF and H horizons, sampled by use of a stratified random sampling procedure, and analyzed for a number of chemical properties. The biogeocoenoses represent Xeric, Mesic, and Hygric sites. The objectives of the study included: characterization of the forest floors in terms of chemical properties, estimation of property variation and sample requirements, selection of properties best suited for distinguishing the forest floors and organic horizons of each site, and examination of nutrient relationships within the forest floors. To assess variability of chemical parameters, 28 properties were used. The values for total nitrogen, iron, manganese, and exchangeable aluminum were found to increase from Xeric to Hygric sites. Increased leaching losses of potassium and calcium and accumulations of iron, aluminum, and manganese occur as the forest floor materials decompose. The least variable horizon in terms of overall sample requirements was the Mesic LF, while the most variable was the Hygric H. The LF horizons on all three sites tended to be less variable than the corresponding H horizons. The chemical properties found to have the least variability were considered to have the best potential for classifying forest floors. These were pH(H₂0), water content of an oven-dried sample, pH (0.01 M CaCl₂), loss on ignition, total carbon, pH (1 N NaCl), and cation exchange capacity measured at pH 7. Least value for prediction of variability and thus for classification were properties such as total manganese, aluminum, iron, calcium, sodium, thickness, exchangeable calcium and magnesium displaced by 1 N NaCl and 1 N NH₄OAc. The second phase of the study selected properties that were best suited for separating the organic horizons and forest floors of the three sites. The properties examined included those measured in the variability study as well as 12 derived or calculated parameters. Two-way analysis of variance in combination with the Student-Newman-Keuls range test was utilized to determine which parameters would best distinguish the forest floors of sites, the LF and H horizons overall, and the horizons of individual sites. The best properties found to separate Xeric, Mesic, and Hygric forest floors were total potassium, exchangeable sodium measured at pH 7, and the ratio of loss on ignition to total carbon. The best parameters for separating LF and H horizons were total potassium, total zinc, exchangeable calcium displaced by 1 N NH₄OAc, exchangeable potassium displaced by 1 N NH₄OAc and 1 N NaCl, pH measured in water and 0.01 M CaCl₂, loss on ignition, base saturation at pH 7, the ratio of total calcium to total magnesium, and the ratio of total calcium to total potassium. The horizons of the individual sites could not all be separated by any individual parameter. The univariate analysis indicated that the order of increasing difficulty of characterization was the LF and H horizons overall, the forest floors of sites, and the horizons of individual sites. A multivariate analysis was performed to find the combination of variables which best distinguishes the horizons of individual sites. Stepwise discriminant analyses using nine, five, and two variables correctly classified 94%, 81%, and 71%, respectively, of the cases examined. The best approach for using multivariate characterization would be to use a minimum number of variables and to include the parameters total nitrogen, potassium, phosphorus, the ratio of loss on ignition to total carbon, and cation exchange capacity measured at pH 4. The final phase of the study examined nutrient relationships in the forest floor horizons as well as the impact of decaying wood and fine roots on forest floor properties. A correlation matrix was produced for the LF and H horizons. The correlation matrices indicated that certain groups of properties were highly correlated and that only one form of the nutrients calcium, magnesium, and potassium need to be measured. The iron, aluminum, and manganese values were highly correlated, which shows that these elements are involved in similar processes, such as biocycling and podzol formation. Several other highly significant correlations indicate that the nutrients calcium, magnesium, and potassium are predominantly in exchangeable forms and that calcium is the dominant cation in these forest floor systems. .Time available for decomposition is the main factor distinguishing LF from H horizons. A final relationship to be examined was the pH-dependent cation exchange capacity. The values for this property increased significantly downslope and significantly greater values were found in the H horizons of each site - a result of increased functional groups associated with the formation of humus. The total nutrient concentrations of decaying wood were measured and compared to the concentrations found in the corresponding LF and H horizons. The decaying wood was found to be a nutrient-deficient material that is distinct from both LF and H horizons. Bulk density measurements demonstrated that the forest floor and decaying wood materials are not significantly different, although the latter material is more variable. .Therefore, decaying wood represents a substantial input of nutrient-deficient biomass to the forest floor. The nutrient concentrations of fine (<2mm) roots were compared with the values obtained for the associated decomposing organic matter. The fine roots were found to be relatively deficient in nitrogen in comparison to the forest floor. Elements such as iron, aluminum, magnesium, and sodium were found to be concentrated in or near fine roots. Thus, decomposing fine roots yield a significant input of nitrogen deficient biomass, cause an increase in the concentration and variability of certain elements, and play an important role in processes such as biocycling and pedogenesis. / Land and Food Systems, Faculty of / Graduate

There is interest in forest sampling methods which have the ability to provide reliable estimates of volume without incurring unreasonable costs. Fraser (1977), to this end, described an individual tree variable probability sampling method which selects sample trees with probabilities based on the areas of polygons derived from triangles. A comparison of some alternative methods of sampling these polygons confirms Fraser's work and demonstrates that the method proposed by him probably has the greatest potential for practical forest sampling. / Forestry, Faculty of / Graduate

White grub is the common name of most scarabaeid larvae and some are considered ! as grubs of economic importance to agricultural crops. Expansion of forestry into previous croplands has resulted in some pests of previous agricultural crops becoming important in forestry. Field trials planted over three seasons, determined the mortality factors influencing the establishment of commercial eucalypt and black wattle plantations in the Natal Midlands. White grubs had the highest pest status. I Characteristic raster pattern was used to identify larvae as a particular morphospecies with the aid of the dissecting microscope. Head I capsule width pattern was used to determine the larval instars responsible for the damage. High incidences of seedling damage was recorded from December to April. Several morphospecies were found I damaging seedlings simultaneously. Morphospecies 1, 2, 3, 4, 5 and 6 were responsible for the damage but morphospecies 1, 2, 4 and 5 were the most predominant. First, second and third instar larvae were found damaging seedlings and ! they sometimes occurred simultaneously. Second and third instar larvae were the predominant larval instars. / Dissertation (M Inst Agrar (Sustainable Insect Management))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

The absence of the majority of conifers from tropical forests remains an unresolved evolutionary and biogeographic enigma. Correlations between a flattened conifer leaf morphology and tropical persistence have led to the hypothesis that shade tolerance is critical for conifer survival in these environments. Yet, little is known of the physiological mechanisms constraining conifer distributions. This dissertation, using the diversity of leaf morphologies and biogeographic distributions found among conifer families, examines this hypothesis from a physiological perspective. The first chapter examines the photosynthetic process in shade-house grown saplings of conifers coexisting in the Central Highlands of Vietnam, an area of unusual tropical conifer diversity. Pinus krempfii, a flat-leaved pine endemic to the densely-canopied tropical forests of Vietnam, demonstrates an intermediate photosynthesis between needle-leaved Pinus and flat-leaved Podocarpaceae, thus providing support for shade tolerance as an important driver of conifer success in tropical forests. In chapter two, respiratory traits are examined in adult conifers growing naturally in the Central Highlands of Vietnam. Flat-leaved conifer species are found to have lower respiration than needle-leaved species. Finally, in chapter 3, the respiratory temperature responses of members from the two largest conifer families, the Pinaceae and Podocarpaceae, are compared. Consistently lower respiration in Podocarpaceae compared to Pinaceae suggests that there are phylogenetic underpinnings to the respiratory differences between the two families. These findings correlate to the biogeographic differences between the two families, with Podocarpaceae being notably more successful in tropical forests than Pinaceae. Together, all three chapters demonstrate that lower foliar carbon fluxes and flattened leaf morphologies are characteristics of a shade tolerance strategy that is necessary for conifer persistence in tropical forests. Ultimately, this dissertation makes a unique link between conifer physiologies and their current biogeographic distributions that will pave the way for a mechanistic tackling of their future survival in a changing climate.

This dissertation investigates the role of listening and sounding in the geopolitics of extractivism, in which the Brazilian Amazon is deeply immersed, by weaving a storytelling of transformation and destruction of places in the region through the tropes of noise and silence. Extractivism here means a process of accumulation by dispossession tied to the tearing apart of places to become resources. The storytelling of this dissertation builds on ethnographic fieldwork in the state of Pará, in the Brazilian Amazon, and the geopolitical testimonies of small farmers, inhabitants of riverine communities, and a social educator, as they articulate relations between the sonic and what they perceive around them, what they are losing, and what they value. I elaborate on a dialogue with and critique of acoustemology as tied to place making by attending to noise and silence as acoustic assemblages tied to modes of making, destroying, sensing, and neglecting place. In the context of radically unequal land distribution, finite land becomes a major contested ontological ground. As places clash, unequal needs of sensing reality as a shared ecosystem come to the fore. Chapter one delves into the way an educator in the Xingu region talks about the silence of the water and the loss of forest and river spirits to neoliberal megaprojects. In dialogue with her words, I explore how silence participates in an economy of extraction in which incompatible notions of nature clash while crystallized sensorial machinations of neoliberalism destroy place from a safe distance. Chapter two debates how soy monoculture farming, in the Low Amazonas Region, fabricates multiple silences as it displaces people, desertifies place, and fills the land with pesticides and mechanisms of surveillance for private property. In dialogue with the testimonies of small rural farmers, and building on my visits to the region, this chapter discusses silences in relation to the desertification and animation of place as part of the cycles of the monoculture extractive chain. The third chapter focuses on the trope of noise as tied to present and potentially changing infrastructures in a riverine community in a conservation unit in the same region. I build on what four inhabitants of this community express about the noise of motors and generators in relation to singing birds and roosters, noting how the storytelling of the relation between these sounding presences is also the storytelling of development as a threat and a promise, in a context where belonging is complexly situated in relation to state tutelage, notions of environmental protection, and NGO projects. Altogether, the storytelling of noise and silence presented in these chapters points to the complicated entanglement between modes of listening and modes of tying being, belonging, and land together, in territories of a region constantly positioned as a resource for extraction.

Patterns and controls of net primary production (NPP) remain a critical question in ecology especially as climate modeling efforts expand. Nutrients, particularly nitrogen (N), can regulate NPP, which couples the N and C cycles. Biological nitrogen fixation (BNF) is the primary natural pathway by which new N enters ecosystems. The magnitude of the natural BNF flux is still not well constrained and the effect of this new N on forest demography and C storage is not well understood. In chapter 1 we use tree census data and two approaches of estimating BNF to make an estimate of the total N fixed by trees across the U.S.: 0.30-0.88 Tg N yr-1 (1.4-3.4 kg N ha-1 yr-1), smaller than previously expected and on par with N inputs from understory or asymbiotic BNF and less than inputs from N deposition. The tree BNF input is dominated by two tree genera: Robinia and Alnus. In chapter 2 we use mixed effect models of forest census data to show that N-fixing trees have no net effect on forest biomass accumulate rate, indicating that though they can fertilize forests on long timescales, during the course of their lives the competitive influences they exert on neighbors balance any fertilization effect they may have. However, the net effect of N-fixing trees on forest development and carbon storage depends on local factors and can be significantly facilitative in contexts where N-fixers are less competitive or when neighbors occupy different forest niches. In chapter 3 we develop a theoretical model which shows lateral leaf litter is a plausible mechanism for observed N-fixer effects, wherein the percent of litter nutrients shared with neighbors can range from almost 0% for small trees to >90% for large isolated trees in low wind, fast decomposition environments. Litter nutrients spread more in windy environments or from trees whose leaf litter falls farther from trees and diffuses more quickly. In sum, N-fixing trees play an important role in temperate forests representing an important N input, however, the flux is smaller than previously expected and the fertilization effect of N-fixing trees is not observed during the census interval.

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