Thesis (Ph.D.)--Indiana University, Dept of Public and Environmental Affairs and the Dept. of Political Science, 2009. / Title from PDF t.p. (viewed on Feb. 8, 2010). Source: Dissertation Abstracts International, Volume: 70-05, Section: A, page: 1775. Adviser: Elinor Ostrom.

The objective of this study was to evaluate the effects of mesquite overstory removal and modifications of soil properties due to mulching treatments on herbaceous production. The three overstory treatments were complete removal of mesquite overstory with no removal of regrowth, complete removal of mesquite overstory with removal of regrowth and an untreated control. The mulching treatments included applications of chip mulch, commercial compost, lopped-and-scattered mesquite branchwood and a control. Both overstory treatments resulted in an increase of over 20% in total annual herbaceous production. The overstory treatment of complete removal of mesquite overstory with no removal of regrowth had the greatest impact on fall production of native herbaceous species during years of relatively high precipitation, at times increasing production by almost 2-fold. Mulching treatments had no effect on herbaceous production; however, soil pH and plant available phosphorus was affected by some of the mulching treatments.

The use of active and passive remote sensing systems for relating forest spatial patterns to fire history was tested over one of the Arizona Sky Islands. Using Landsat Thematic Mapper (TM), Shuttle Imaging Radar (SIR-C), and data fusion I examined the relationship between landscape metrics and a range of fire history characteristics. Each data type (TM, SIR-C, and fused) was processed in the following manner: each band, channel, or derived feature was simplified to a thematic layer and landscape statistics were calculated for plots with known fire history. These landscape metrics were then correlated with fire history characteristics, including number of fire-free years in a given time period, mean fire-free interval, and time since fire. Results from all three case studies showed significant relationships between fire history and forest spatial patterns. Data fusion performed as well or better than Landsat TM alone, and better than SIR-C alone. These comparisons were based on number and strength of significant correlations each method achieved. The landscape metric that was most consistent and obtained the greatest number of significant correlations was Shannon's Diversity Index. Results also agreed with field-based research that has linked higher fire frequency to increased landscape diversity and patchiness. An additional finding was that the fused data seem to detect fire-related spatial patterns over a range of scales.

Computer models used to predict the pattern and rate of spread of fire in grasslands as well as other vegetation types rely on various inputs for their calculations. Because of the direct effect they have on the quantity of fuel available to carry a fire and the effects of moisture on the potential for fuel available to carry a fire and the effects of moisture on the potential for fuel to begin burning and to sustain a fire, fuel loading measurements, which are similar to production measurements in grasslands, and estimates of fuel moisture are two important variables to be considered when modeling fire behavior. The objective of this project is to determine if there is a relationship between measured environmental variables and the fuel moisture values at the same sample points which can be modeled with GIS data and neural networks. This study was carried out using a combination of field sampled data and common GIS data layers. The results demonstrate the potential for neural network analysis in this type of environmental problem.

Ecosystem management is positioned as the modern paradigm of resource management. Fire management activities within the natural resource management agencies, under the adoption of an ecosystem management approach, supports an increased focus upon prescribed and manager-ignited fire programs. A review of past national fire policies and the effects they have had upon ecosystem conditions today further supports the role for prescribed fire. Under an ecosystem management approach, resource managers need to consider the effects of fire management activities over longer temporal and broader spatial scales. Examining the ecological, social, political, and economic aspects surrounding fire management activities on these scales will help ensure healthier ecosystems in perpetuity. Although the suppression of wildfires will remain a necessary component to fire management activities today, there needs to be an increased effort to reintroduce fire into ecosystems and to recognize fire as a natural component vital to maintaining ecosystem health.

The research accomplished in this dissertation used both mathematical and statistical techniques to extract and evaluate measures of landscape temporal dynamics and spatial structure from remotely sensed data for the purpose of mapping wildlife habitat. By coupling the landscape measures gleaned from the remotely sensed data with various sets of animal sightings and population data, effective models of habitat preference were created. Measures of temporal dynamics of vegetation greenness as measured by National Oceanographic and Atmospheric Administration's Advanced Very High Resolution Radiometer (AVHRR) satellite were used to effectively characterize and map season specific habitat of the Sonoran pronghorn antelope, as well as produce preliminary models of potential yellow-billed cuckoo habitat in Arizona. Various measures that capture different aspects of the temporal dynamics of the landscape were derived from AVHRR Normalized Difference Vegetation Index composite data using three main classes of calculations: basic statistics, standardized principal components analysis, and Fourier analysis. Pronghorn habitat models based on the AVHRR measures correspond visually and statistically to GIS-based models produced using data that represent detailed knowledge of ground-condition. Measures of temporal dynamics also revealed statistically significant correlations with annual estimates of elk population in selected Arizona Game Management Units, suggesting elk respond to regional environmental changes that can be measured using satellite data. Such relationships, once verified and established, can be used to help indirectly monitor the population. Measures of landscape spatial structure derived from IKONOS high spatial resolution (1-m) satellite data using geostatistics effectively map details of Sonoran pronghorn antelope habitat. Local estimates of the nugget, sill, and range variogram parameters calculated within 25 x 25-meter image windows describe the spatial autocorrelation of the image, permitting classification of all pixels into coherent units whose signature graphs exhibit a classic variogram shape. The variogram parameters captured in these signatures have been shown in previous studies to discriminate between different species-specific vegetation associations. The synoptic view of the landscape provided by satellite data can inform resource management efforts. The ability to characterize the spatial structure and temporal dynamics of habitat using repeatable remote sensing data allows closer monitoring of the relationship between a species and its landscape.

The primary goal of my study was to evaluate strategies for promoting local support for wildlife conservation in Masai Mara National Reserve (MMNR) and the adjacent group ranches. This was done by determining the effects of the changing land tenure from communal to individual on the Maasai lives and wildlife, and the role of the revenue sharing program in enhancing support for wildlife conservation. The study used local people's suggestions to recommend strategies for improving revenue sharing. A combination of literature review, questionnaire-based surveys and participant observation methods were used to achieve these goals. The maintenance of a viable ecosystem in Mara has succeeded due to the traditionally benign relationship between the Maasai and wildlife. However, various factors continue to strain this relationship. First, increasing human population and encroachment of agriculture has diminished areas available for livestock and wildlife grazing. Second, the absence of compensation for loss of life and property to wildlife and inadequacy of the revenue sharing has increased people's antagonism towards wildlife. Third, since the local people are excluded from the management of MMNR and wildlife in general, they consider these activities external impositions. Fourth, subdivision of group ranches will severely reduce the land available for livestock and wildlife grazing and eliminate the traditional resource sharing strategy that has sustained the Maasai for centuries. This study also revealed that although the Maasai harbor many negative feelings towards MMNR, they consider it an important asset. Further, they are unwilling to give up pastoralism and expect to continue with communal grazing after subdivision which, is good for wildlife conservation. In view of this, I made the following recommendations: implement a regional land management system with a core wildlife area (the reserve) and a wildlife management-pastoral area surrounding the core, and designated zones for agriculture; support the above system with firm government policies and incentives; redesign the revenue sharing program to cover all the affected people; promote policies that encourage diversified wildlife-based enterprises including consumptive use; transfer much of the wildlife management responsibilities to the local people.

In contrast to documented increases in woody plant dominance of former savannas and grasslands of North America, oak (Quercus L.) savannas that form lower treelines in the southwestern United States and northwestern Mexico have been relatively stable over the past millennium. This research identified potential biotic and abiotic constraints on seedling recruitment of Quercus emoryi Torr. (Emory oak) within the context of potential shifts in lower treeline. Field surveys were used to describe seedling distribution at and below lower treeline, and to determine the potential for acorn dispersal from lower treeline into adjacent grassland. Field and greenhouse experiments designed to determine constraints on seedling establishment included reciprocal soil transfers, nutrient amendment studies, provision of artificial shade, and manipulation of seasonal precipitation inputs. Results indicate that rates of Q. emoryi recruitment within grasslands below treeline are relatively low, and are constrained by low rates of seed dispersal coupled with a low probability of seedling emergence. Seedling recruitment rates were directly correlated with quantity of summer precipitation, but were independent of winter precipitation. Results of this and complementary research suggest that lower treeline in southern Arizona is stabilized by self-enhancing feedback mechanisms of overstory shade, seed dispersal, and seedling establishment coupled with strong abiotic constraints beyond the current ecotone. The observed shift in treeline in the last millennium was less likely the result of slow, spatial progression of autogenic safe sites than the result of episodic and infrequent allogenic processes that simulated, or negated the importance of, conspecific, biogenic safe sites. Increases in summer precipitation are one such process that would facilitate (historic or potential future) downslope shifts in lower treeline. This interpretation is consistent with observations that downslope shifts in lower treeline which occurred 700-1700 ybp coincided with a period of particularly high summer precipitation in the region (i.e., the "Medieval Warm" period, 645-1295 ybp).

It has long been asserted that taxation distorts the production decisions of timber land owners. More recently, claims have been that this does not occur because the tax is fully shifted into sawlog prices. This paper constructs a model of landowner choice between a property tax programme and a modified yield tax programme under the assumption of tax capitalization. Under tax shifting, the landowner will be indifferent between tax regimes. With tax capitalization owners of younger stands will elect to classify their stands for the modified yield tax programme. An empirical model of binary choice is evaluated using cross sectional forty level data from Cowlitz County, Washington immediately after implementation of the Reforestation Act of 1931. The empirical results suggest that landowners are responsive to differences in the taxing pattern in a manner conforming to the theoretical predictions consistent with tax capitalization. Additional results suggest that implementation of the alternate tax regime may have had little effect on tax defaults. The tax capitalization result is extended to derive expressions for pigouvian taxes designed to influence stand management, consistent with the increasing timber prices encountered in the postwar world.

Because recent conflicts over U.S. Forest Service decisions may indicate that the public lacks confidence in the agency, this study sought to discover the level of and reasons for confidence in the Forest Service. Results of a nationwide mail survey of participants in Forest Service planning showed that 43% of respondents had a low level of confidence in their local Forest Service office and 55% had a low level of confidence in the agency at the national level. The survey also revealed that participants' judgments of the procedural fairness of the planning process had an important influence on confidence in the agency at both the local and national level. Judgments about the fairness of agency procedures were much more important determinants of confidence than the level of benefits participants received from the forests or their policy preferences, judgments about distributive fairness, socio-demographic characteristics or styles of participation.