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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.
51

AN ASSESSMENT OF RESIDUE UTILIZATION AT MASSACHUSETTS SAWMILLS (FINANCIAL, ECONOMIC)

DENNISON, STEVEN E 01 January 1984 (has links)
A general assessment model of industrial wood residue use was devised and tested using the sawmill industry in Massachusetts. Two analytical approaches were used in the model. The first employs financial analyses of individual mills (in various production strata) to determine the profitability of their residue operations. An economic analysis used to determine the need for public intervention is also part of this approach. The second part of the model utilizes a scoring technique to evaluate the technical components in the sawmill's residue operation. It is intended primarily as a tool to complement the economic analysis in the first approach. Sixty individual firms, comprising 40 percent of the State's sawmill industry population in 1980, responded to a questionnaire survey aimed at examining their residue operations. Residue prices and equipment costs (obtained from primary and secondary data sources) were applied to the annual physical flow of residues and equipment at each mill. From these data cash flows for the evaluation period of each residue operation were developed. The residue inventory indicated that 86 percent of all residues generated in Massachusetts were sold. According to the net present worth values calculated in the financial analyses, 95 percent of all sawmills selling their residues did so at a profit. Residue operations at the other mills could be improved mainly through changes in equipment use, residue pricing, and greater attention to marketing. Because of the general profitability of residue operations in the state, an economic analysis was not conducted for this study. For the technical components analysis, the establishment of a standard threshold value allowed operations to be compared on a technical basis to other mills in the same production class. The threshold index also provided a ranking that could be used in determining the need for public intervention under a limited budget.
52

IMPACT OF SWIDDEN AGRICULTURE AND SUBSISTENCE HUNTING ON DIVERSITY AND ABUNDANCE OF EXPLOITED FAUNA IN THE ITURI FOREST OF NORTHEASTERN ZAIRE (PYGMY)

WILKIE, DAVID SCOTT 01 January 1987 (has links)
This 18 month study examined the impact of long-term recurrent roadside swidden cultivation and subsistence hunting on the composition and abundance of exploited fauna and the ability of roadside post agricultural regrowth vegetation to support exploitable populations of these animals. A computer model was also developed to graphically represent the spatial patterning of horticultural land-use and forest vegetation regeneration under a variety of demographic and land-use conditions. Track counts and pellet group counts in conjunction, are an effective means to estimate faunal composition and relative abundance within a tropical moist forest. Densities of forest duikers, which are most commonly exploited and are the most important species group dietarily, are comparable in post-agricultural regrowth forest and uncut forest within 5km of the road. Hunting success and bushmeat capture weights are comparable from hunts conducted in regrowth and uncut forest. Hunters concentrate 56% of their effort in regrowth forest that constitutes only 26% of the available forest within 3km of the road. Given that subsistence hunting pressure is greater in regrowth forest within 3km of the road and that ungulate densities are comparable in regrowth and uncut forest, this study concludes that post-agricultural forest can and does provide substantial and sustained quantities of bushmeat for consumption by local human populants and may support a higher biomass of exploitable fauna than comparable areas of uncut forest. The ability of forest faunal populations to withstand the intensive exploitation associated with widespread market hunting is however dubious. The spatial patterning of horticultural land-use in the Ituri forest can be effectively stimulated using a very simple set of rules to govern forest clearing and post-abandonment regeneration.
53

AN ECONOMIC ANALYSIS OF THE FOREST TAXATION LAW IN MASSACHUSETTS

KRONRAD, GARY DOUGLAS 01 January 1982 (has links)
Ad valorem taxation is usually considered to inhibit forest management. In order to reduce the problems caused by ad valorem taxation, Massachusetts has enacted a modified assessment-yield tax law. Chapter 61 provides that owners of ten or more contiguous acres of forest land, who are willing to manage their land under a planned program of forest management aimed at improving the quantity and quality of a continuous forest crop, may qualify to have their forest land assessed at not more than $10 per acre. In return for this tax reduction the landowner must pay to his local town a tax of 8 percent of the value of the stumpage for any products harvested. The main thrust of this study was to determine if Chapter 61 is an efficient and effective program for increasing the level of forest management and output on privately owned forest lands. This was accomplished by performing five analyses. In the first analysis, four benefit-cost ratios were calculated to evaluate the economic efficiency and effectiveness of the Chapter 61 program. Cost price analysis was used the determine the cost of producing the marginal physical timber product under the rules and regulations of Chapter 61. Cost minimization analysis was employed to determine the amount of money saved by the average landowner by classifying his property under Chapter 61. This analysis gives an indication of the possible "excess" subsidy given to a landowner. The fourth analysis performed is the calculation of the value of forest land classified under Chapter 61. This calculation is useful for formulating forest taxation policies and especially relevant if the site productivity approach to forest land taxation is utilized. The fifth analysis performed evaluated the impact of Chapter 61 on town financing for a sample of towns. Results of this study indicate that Chapter 61 is a viable alternative to ad valorem taxation but could be improved.
54

Soil moisture, forest productivity and ecological land classification in central Massachusetts

Leighton, Adrian D 01 January 2005 (has links)
Throughout much of the United States, systems of ecological land classification are used to divide the forested landscape into units that are biologically and operationally meaningful. No such system currently exists in central Massachusetts, however, due to the extensive and prolonged effects of human land use. Initial research on a series of State Forests in central Massachusetts indicate that physical site characteristics such as the presence of a hardpan, soil texture and type of glacial deposition can be correlated with patterns in vegetation distribution. These factors are similar to those used by W. B. Leak in creating an ecological land type (ELT) classification for the White Mountain National Forest in New Hampshire. A system was created to adapt and transfer the White Mountain ELTs to central Massachusetts. The system was then applied to a variety of sites in central Massachusetts at two different scales. The habitat classification system reflected general trends of vegetation composition and productivity, particularly at a local landscape level, but further work is needed to better account for the effect of land use history and local ecological variation. An underlying assumption of ecological land classification is that vegetation is most strongly influenced by site factors that are related to soil moisture availability. Direct soil moisture measurements were made on a variety of sites throughout a season at Cadwell Memorial Forest in Pelham, Massachusetts. Analysis showed a relatively poor correlation between soil moisture measured that year and long-term site productivity. However, the pattern of short term (weekly) variation in soil moisture was related to general trends in productivity. The hydrologic model, TOPMODEL, was used to create a relative wetness potential index within a GIS framework to predict site productivity based on potential soil moisture availability. While this model showed some potential in predicting general soil moisture status, it was not well correlated with the direct soil moisture measurements.
55

MORTALITY PATTERNS OF RADIO-MARKED COYOTES IN JACKSON HOLE, WYOMING

TZILKOWSKI, WALTER MATTHEW 01 January 1980 (has links)
Coyote (Canis latrans) mortality was measured in Jackson Hole, Wyoming. The study area included portions of Grand Teton National Park, National Elk Refuge and Bridger-Teton National Forest. Coyote exploitation is prohibited on both the National Park and Refuge, environments minimally influenced by man. Ninety-two coyotes, 43 males and 49 females, at least 4 months of age or older, were captured during 5 trapping periods from December 1973 to September 1976. Coyotes were collared with radio telemetric transmitters which revealed geographic location and served as mortality indicators. Thirty-three pups ((LESSTHEQ) 7 weeks) were ear-tagged; two were subsequently captured and radio-marked. Forty-one radio-marked coyotes, 18 males and 23 females, were recovered. Only 1 ear-tagged pup was recovered. A positive linear relationship existed between recovery time (days) and age (years) at marking. Eighty-five % (N = 41) of the recoveries were during September through May. Ninety-three % of the mortalities were man-caused. Mortality causes of recovered coyotes included: shot, 80.5%; trapped, clubbed, snow-machined and starvation, 2.4%; road-killed and unknown, 4.9%. Annual (June to subsequent May) recovery rates were: 1974-75, 25% (N = 47); 1975-76, 5% (N = 18); and 1976-77, 40% (N = 25). Recovery rates from marking to recovery from the composite sample were: year 0, 26% (N = 90); year 1, 18% (N = 65); and year 2, 8% (N = 47). Shooting mortality rates (h(,x)) for the 0 years since marking class of the young-of-the-year Jackson Hole coyotes (0.4194) were compared to rates from Curlew Valley (0.3125) and Yellowstone National Park (0.2531). Mean total mortality rates (q) were: 0.7339, Curlew Valley; 0.5596, Yellowstone National Park; and 0.4561, Jackson Hole. The mean total mortality rate (q) was 0.3783 and the mean shooting mortality (h) was 0.2540 for Jackson Hole coyotes. Monthly survival rates were higher in 1975-76 that 1974-75. Female young-of-the-year survival was less (P = 0.03) for 1974-75 than 1975-76. There was no difference (P > 0.05) between years in survival rates for males or adult and yearling females. Estimates of areas of utilization (22 January 1975 to 22 April 1975) were computed for 19 coyotes. The mean area of utilization of 5 adult or yearling males was 35.5 km('2) (+OR-) 18.9, and for 13 adult or yearling females was 70.1 (+OR-) 80.3. Coyotes radio-marked primarily in Grand Teton National Park and the National Elk Refuge had mortality patterns similar to other coyote populations exploited by man.
56

The influence of logwood on British Honduras from its beginning to 1800

Bigger, Ruth Eleanor January 1941 (has links)
No description available.
57

Patterns of visitor use and seasonal changes in campsite condition associated with site design, soil texture, and vegetative cover type

Scoles, Frederick Grant January 1977 (has links)
No description available.
58

Structural attributes, disturbance dynamics, and ecosystem properties of old-growth forests in western Massachusetts

D'Amato, Anthony William 01 January 2007 (has links)
Natural disturbance patterns, forest structural attributes, patterns of nitrogen availability, and the abundance and composition of understory vegetation were studied in eighteen old-growth stands in western Massachusetts. Dendroecological analyses indicated that disturbance regimes for these systems were dominated by relatively frequent, low intensity disturbances (average of 5.0% canopy area disturbed per decade) operating randomly on the landscape. Comparisons of dendroecological patterns with model simulations of past hurricane events and historical documents suggested that broad-scale disturbances, such as hurricanes and ice storms, resulted in common disturbance peaks in the 1790s, 1820s, and 1920s at several study areas separated by over 50 km. No stand-replacing disturbances were detected at any old-growth area during the period examined (1700-1989). Comparisons of structural characteristics in old-growth and second-growth hemlock forests illustrated that old-growth stands exhibit a higher degree of structural complexity compared to second-growth hemlock forests. In particular, old-growth stands had larger overstory trees and a greater abundance of downed coarse woody debris (135.2 versus 33.2 m3/ha) and snags (21.2 versus 10.7 m3/ha) compared to second-growth systems. The range in variation of structural attributes within my old-growth study areas was similar to those in other old-growth eastern hemlock forests located on more moderate terrain in the Upper Midwest and New York. This range in variation was related to differences in disturbance history and site productivity among old-growth stands. Soil measurements indicated that there were no detectable differences in soil characteristics, such as total C and N, between old-growth and second-growth hemlock stands; however, inorganic N (NO3-N and NH4-N) availability was much greater in old-growth stands. In contrast, differences existed in soil characteristics and N availability between old-growth hemlock and old-growth northern hardwood forests, with hardwood dominated systems exhibiting lower forest floor C:N ratios and greater amounts of inorganic N. Old-growth hemlock stands had higher species richness and diversity, as well as a greater abundance of understory herbs and shrubs, and tree seedlings and saplings compared to second-growth forests. In addition, several common understory plants, including Aralia nudicaulis, Dryopteris intermedia , and Viburnum alnifolia, were more abundant in old-growth stands.
59

THE EFFECTS OF LAND USE AND LAND USE CHANGE ON THE YIELDS OF STREAMS IN MASSACHUSETTS.

MRAZIK, BRIAN REED 01 January 1976 (has links)
The effects of land use and land use change on the yields of 42 watersheds in Massachusetts were evaluated over the 20 year period from 1952 to 1971. Land use data for each watershed was determined from aerial photography taken in 1951-52 and again in 1971-72. Average annual and seasonal water yields were related to various climatic, topographic and land use variables using multiple regression techniques. Changes in annual and seasonal runoff were determined by time regression analyses of runoff deviations from estimates made by three different hydrologic models, and then related to changes in land use by simple correlation techniques. Results indicated that the average 20 year yields were most strongly related to land use factors during the growing season when vegetation was actively transpiring. Growing season runoff was inversely correlated with the percentage. of watershed area in forest and positively correlated with the percentage in agricultural and urban types.
60

White ash decline in Massachusetts: The role of site and climate factors

Woodcock, Hilary 01 January 1993 (has links)
White ash increased in basal area between 1962 to 1979 on continuous forest inventory (CFI) plots in Massachusetts, but 20% of 82 ash plots ($>$10% basal area ash) were classified as decline (from growth and mortality rates). Reclassification of 18 plots on the basis of % crown dieback in 1991 validated the decline classification system and indicated little change in plot decline status in the past decade. Mortality of dominant and co-dominant trees was associated with sites characterized by a high landscape position and soils shallow to bedrock (R$\sp2$ = 0.6926, p = 0.0007). Ephemeral streams were common; these sites would be prone to fluctuations in moisture supply. Similar relationships were identified on three 2 ha intensive study sites. Distribution of decline-prone microsite types and decline of ash was highly heterogeneous on the study sites (but not on the CFI plots). Tree-ring analysis showed that trees growing on 'decline-prone' sites were sensitive to drought (measured by growing year Palmer Drought Severity Index) and indicated that the present episode of decline on these sites began in the 1960s, the most severe drought period since 1836. Ash yellows was identified on one and possibly the second of the two study sites with ash decline, and on two of the three decline CFI plots resampled in 1991. Sites with a SI $>$ 80 supported healthy trees in 1991. For sites with a SI $<$ 80, a decline index estimated from landscape position and soil moisture predicted the distribution of decline on the two intensive study sites on which ash decline was present and shows promise as a method of evaluating sites for their potential for ash decline. The relationship between decline and site factors was unique to white ash among several species tested (i.e. it was species-specific). On ash decline sites, red oak and sugar maple increased in relative importance.

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