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In much of Australia and the United States, the almost universal right to have a house on rural allotments has resulted in rural living settlement in areas intended, by land use planning policy, to be used for agriculture. Such ‘unplanned’ rural living has a range of potential adverse impacts, including, among other things, loss of agricultural production, land use conflicts with agriculture, land value constraints on farm restructuring, and changes to the rural landscape character. Given the strongly held community perception of a house as a development right, this research was motivated by the need to understand the effects of that right, in order to assess the potential value of any change in policy. An integral consideration was the influence of the size of allotments with any such right. The research was also driven by an interest in explaining the pattern of unplanned rural living settlement, i.e. why are particular allotments converted and others not? Largely in the absence of previous studies of unplanned rural living as a distinct phenomenon, there was scope for this thesis to make a contribution to knowledge in these respects. The research involved three stages of empirical analysis. Firstly, a Queensland-wide survey of land use conversion from sugarcane production supported the choice of the Bundaberg region as the study area. Contingency table analyses were then conducted into the current land use and other attributes of land in the study area that, in 1980, was used for sugarcane. Those analyses identified distinguishing attributes of the different land use sub-sets of allotments, and informed the selection of observation units for the third stage. The third stage provided the principal basis for fulfilling the research objectives. It focused on logit models of the choice, at the time of sale, between using a particular allotment for unplanned rural living or sugarcane production. Those analyses provided an indication of the role of individual land attributes while controlling for the effects of other attributes. It was found there had been limited conversion of suitable, productive sugarcane land to unplanned rural living. Compared to those allotments that remained in sugarcane production, allotments converted to rural living were, on average, much smaller, of less value, had lower agricultural production potential, and were situated in more undulating and forested landscapes further from Bundaberg. These clear distinctions between rural living and sugarcane allotments contributed to logit models with high explanatory power. The expected productive income of allotments had overwhelming weight and was highly statistically significant in explaining the land use choice between unplanned rural living and sugarcane. This is a notable finding, because some other studies have not shown such a strong relationship between land use and measures such as soil productivity. There was a degree of natural coincidence between more undulating and forested landscapes and lower productive potential. Notably, landscape attributes appeared to be of secondary importance in determining land use. The presence of a house at the time of sale was not a statistically significant explanatory factor for land use. This finding, together with that of limited conversion of suitable, productive land to unplanned rural living, meant there was a lack of evidence to support a change to the right to have a house on rural allotments. The findings did indicate that the allotment area required to avoid conversion to unplanned rural living was different to the area required for agricultural viability. In the circumstances of this study area and period, 20 ha would have been an acceptable minimum to retain suitable cropping land in productive use. This is compared to the 60 ha suggested as necessary for farm viability. However, the potential for changed economic conditions to reduce the productive value of agricultural land, and increase demand for rural living, makes it appropriate to be cautious about permitted allotment sizes. A detailed conceptual framework informed the selection of observation units and variables for the third stage of analyses. The framework helped to confirm allotment sales as the observation units, and provided the rationale for excluding the difficult to measure influences of a landowner’s attachment to the land, and inertia, as explanatory variables. The high explanatory power of the logit models provides support for the approach, which may be useful in future studies.

In much of Australia and the United States, the almost universal right to have a house on rural allotments has resulted in rural living settlement in areas intended, by land use planning policy, to be used for agriculture. Such ‘unplanned’ rural living has a range of potential adverse impacts, including, among other things, loss of agricultural production, land use conflicts with agriculture, land value constraints on farm restructuring, and changes to the rural landscape character. Given the strongly held community perception of a house as a development right, this research was motivated by the need to understand the effects of that right, in order to assess the potential value of any change in policy. An integral consideration was the influence of the size of allotments with any such right. The research was also driven by an interest in explaining the pattern of unplanned rural living settlement, i.e. why are particular allotments converted and others not? Largely in the absence of previous studies of unplanned rural living as a distinct phenomenon, there was scope for this thesis to make a contribution to knowledge in these respects. The research involved three stages of empirical analysis. Firstly, a Queensland-wide survey of land use conversion from sugarcane production supported the choice of the Bundaberg region as the study area. Contingency table analyses were then conducted into the current land use and other attributes of land in the study area that, in 1980, was used for sugarcane. Those analyses identified distinguishing attributes of the different land use sub-sets of allotments, and informed the selection of observation units for the third stage. The third stage provided the principal basis for fulfilling the research objectives. It focused on logit models of the choice, at the time of sale, between using a particular allotment for unplanned rural living or sugarcane production. Those analyses provided an indication of the role of individual land attributes while controlling for the effects of other attributes. It was found there had been limited conversion of suitable, productive sugarcane land to unplanned rural living. Compared to those allotments that remained in sugarcane production, allotments converted to rural living were, on average, much smaller, of less value, had lower agricultural production potential, and were situated in more undulating and forested landscapes further from Bundaberg. These clear distinctions between rural living and sugarcane allotments contributed to logit models with high explanatory power. The expected productive income of allotments had overwhelming weight and was highly statistically significant in explaining the land use choice between unplanned rural living and sugarcane. This is a notable finding, because some other studies have not shown such a strong relationship between land use and measures such as soil productivity. There was a degree of natural coincidence between more undulating and forested landscapes and lower productive potential. Notably, landscape attributes appeared to be of secondary importance in determining land use. The presence of a house at the time of sale was not a statistically significant explanatory factor for land use. This finding, together with that of limited conversion of suitable, productive land to unplanned rural living, meant there was a lack of evidence to support a change to the right to have a house on rural allotments. The findings did indicate that the allotment area required to avoid conversion to unplanned rural living was different to the area required for agricultural viability. In the circumstances of this study area and period, 20 ha would have been an acceptable minimum to retain suitable cropping land in productive use. This is compared to the 60 ha suggested as necessary for farm viability. However, the potential for changed economic conditions to reduce the productive value of agricultural land, and increase demand for rural living, makes it appropriate to be cautious about permitted allotment sizes. A detailed conceptual framework informed the selection of observation units and variables for the third stage of analyses. The framework helped to confirm allotment sales as the observation units, and provided the rationale for excluding the difficult to measure influences of a landowner’s attachment to the land, and inertia, as explanatory variables. The high explanatory power of the logit models provides support for the approach, which may be useful in future studies.

In much of Australia and the United States, the almost universal right to have a house on rural allotments has resulted in rural living settlement in areas intended, by land use planning policy, to be used for agriculture. Such ‘unplanned’ rural living has a range of potential adverse impacts, including, among other things, loss of agricultural production, land use conflicts with agriculture, land value constraints on farm restructuring, and changes to the rural landscape character. Given the strongly held community perception of a house as a development right, this research was motivated by the need to understand the effects of that right, in order to assess the potential value of any change in policy. An integral consideration was the influence of the size of allotments with any such right. The research was also driven by an interest in explaining the pattern of unplanned rural living settlement, i.e. why are particular allotments converted and others not? Largely in the absence of previous studies of unplanned rural living as a distinct phenomenon, there was scope for this thesis to make a contribution to knowledge in these respects. The research involved three stages of empirical analysis. Firstly, a Queensland-wide survey of land use conversion from sugarcane production supported the choice of the Bundaberg region as the study area. Contingency table analyses were then conducted into the current land use and other attributes of land in the study area that, in 1980, was used for sugarcane. Those analyses identified distinguishing attributes of the different land use sub-sets of allotments, and informed the selection of observation units for the third stage. The third stage provided the principal basis for fulfilling the research objectives. It focused on logit models of the choice, at the time of sale, between using a particular allotment for unplanned rural living or sugarcane production. Those analyses provided an indication of the role of individual land attributes while controlling for the effects of other attributes. It was found there had been limited conversion of suitable, productive sugarcane land to unplanned rural living. Compared to those allotments that remained in sugarcane production, allotments converted to rural living were, on average, much smaller, of less value, had lower agricultural production potential, and were situated in more undulating and forested landscapes further from Bundaberg. These clear distinctions between rural living and sugarcane allotments contributed to logit models with high explanatory power. The expected productive income of allotments had overwhelming weight and was highly statistically significant in explaining the land use choice between unplanned rural living and sugarcane. This is a notable finding, because some other studies have not shown such a strong relationship between land use and measures such as soil productivity. There was a degree of natural coincidence between more undulating and forested landscapes and lower productive potential. Notably, landscape attributes appeared to be of secondary importance in determining land use. The presence of a house at the time of sale was not a statistically significant explanatory factor for land use. This finding, together with that of limited conversion of suitable, productive land to unplanned rural living, meant there was a lack of evidence to support a change to the right to have a house on rural allotments. The findings did indicate that the allotment area required to avoid conversion to unplanned rural living was different to the area required for agricultural viability. In the circumstances of this study area and period, 20 ha would have been an acceptable minimum to retain suitable cropping land in productive use. This is compared to the 60 ha suggested as necessary for farm viability. However, the potential for changed economic conditions to reduce the productive value of agricultural land, and increase demand for rural living, makes it appropriate to be cautious about permitted allotment sizes. A detailed conceptual framework informed the selection of observation units and variables for the third stage of analyses. The framework helped to confirm allotment sales as the observation units, and provided the rationale for excluding the difficult to measure influences of a landowner’s attachment to the land, and inertia, as explanatory variables. The high explanatory power of the logit models provides support for the approach, which may be useful in future studies.

In much of Australia and the United States, the almost universal right to have a house on rural allotments has resulted in rural living settlement in areas intended, by land use planning policy, to be used for agriculture. Such ‘unplanned’ rural living has a range of potential adverse impacts, including, among other things, loss of agricultural production, land use conflicts with agriculture, land value constraints on farm restructuring, and changes to the rural landscape character. Given the strongly held community perception of a house as a development right, this research was motivated by the need to understand the effects of that right, in order to assess the potential value of any change in policy. An integral consideration was the influence of the size of allotments with any such right. The research was also driven by an interest in explaining the pattern of unplanned rural living settlement, i.e. why are particular allotments converted and others not? Largely in the absence of previous studies of unplanned rural living as a distinct phenomenon, there was scope for this thesis to make a contribution to knowledge in these respects. The research involved three stages of empirical analysis. Firstly, a Queensland-wide survey of land use conversion from sugarcane production supported the choice of the Bundaberg region as the study area. Contingency table analyses were then conducted into the current land use and other attributes of land in the study area that, in 1980, was used for sugarcane. Those analyses identified distinguishing attributes of the different land use sub-sets of allotments, and informed the selection of observation units for the third stage. The third stage provided the principal basis for fulfilling the research objectives. It focused on logit models of the choice, at the time of sale, between using a particular allotment for unplanned rural living or sugarcane production. Those analyses provided an indication of the role of individual land attributes while controlling for the effects of other attributes. It was found there had been limited conversion of suitable, productive sugarcane land to unplanned rural living. Compared to those allotments that remained in sugarcane production, allotments converted to rural living were, on average, much smaller, of less value, had lower agricultural production potential, and were situated in more undulating and forested landscapes further from Bundaberg. These clear distinctions between rural living and sugarcane allotments contributed to logit models with high explanatory power. The expected productive income of allotments had overwhelming weight and was highly statistically significant in explaining the land use choice between unplanned rural living and sugarcane. This is a notable finding, because some other studies have not shown such a strong relationship between land use and measures such as soil productivity. There was a degree of natural coincidence between more undulating and forested landscapes and lower productive potential. Notably, landscape attributes appeared to be of secondary importance in determining land use. The presence of a house at the time of sale was not a statistically significant explanatory factor for land use. This finding, together with that of limited conversion of suitable, productive land to unplanned rural living, meant there was a lack of evidence to support a change to the right to have a house on rural allotments. The findings did indicate that the allotment area required to avoid conversion to unplanned rural living was different to the area required for agricultural viability. In the circumstances of this study area and period, 20 ha would have been an acceptable minimum to retain suitable cropping land in productive use. This is compared to the 60 ha suggested as necessary for farm viability. However, the potential for changed economic conditions to reduce the productive value of agricultural land, and increase demand for rural living, makes it appropriate to be cautious about permitted allotment sizes. A detailed conceptual framework informed the selection of observation units and variables for the third stage of analyses. The framework helped to confirm allotment sales as the observation units, and provided the rationale for excluding the difficult to measure influences of a landowner’s attachment to the land, and inertia, as explanatory variables. The high explanatory power of the logit models provides support for the approach, which may be useful in future studies.

Fisheries managers have the potential to significantly improve reef fish management in the Gulf of Mexico through the use of ecosystem-based approaches to fisheries management. Ecosystem-based approaches are needed to address the effects of fishing on trophodynamic interactions, to better account for ecosystem-scale processes in model projections, and to recognize the short and long-term biomass tradeoffs associated with making regulatory choices. My research was concentrated around three objectives: (1) characterizing the trophodynamic interactions between Gulf of Mexico fishes, in order to construct an invaluable tool (a Gulf of Mexico Atlantis model) to be used in ecological hypothesis testing and policy performance evaluation for years to come; (2) predicting ecological indicators for the Gulf of Mexico that both respond to fishing pressure and are robust to observational error, and; (3) evaluating the performance of an ecosystem-based policy options for managing reef fish species in the Gulf of Mexico. To accomplish these objectives, a spatial, trophodynamic ecosystem model- Atlantis, was employed to represent the Gulf of Mexico marine ecosystem. To characterize trophic interactions between modeled species, I applied a maximum likelihood estimation procedure to produce Dirichlet probability distributions representing the likely contribution of prey species to predators’ diets. This provided mode values (the peak of the distribution) and associated error ranges, which describe the likely contribution of a prey item in a predator’s diet. The mode values were used to parameterize the availabilities (diet) matrix of the Gulf of Mexico Atlantis model. Investigating trophic interactions was useful for determining which species within the Atlantis model were data rich, and justified the emphasis on reef fish species and their prey items in subsequent analyses. Once parameterized and calibrated, I used the Atlantis model to project ecological indicators over a 50 year time horizon (2010-2060) under varying levels of fishing mortality. Principal component analysis was used to evaluate ecological indicator trajectories in multivariate space, to rank indicators according to how well they describe variability in ecosystem structure (termed ‘importance’), to reveal redundancies in the information conveyed, to quantify interannual noise and to determine how robust indicators are to observational error. Reef fish catch, Red snapper biomass, King mackerel biomass and Species richness indicators ranked the highest in terms of importance and robustness to error and in having low levels of interannual noise (i.e., requiring less frequent monitoring). I then used a management strategy evaluation (MSE) framework in Atlantis to evaluate some of these same indicators under an ecosystem-based approach to fisheries management – using robust harvest control rules to manage reef fishes. I found that this ecosystem-based policy option was able to maintain higher reef fish biomass, catch and ecosystem-wide biodiversity under any given level of fishing mortality when compared to a status quo management approach. These results suggest that harvesting under the HCRs encourages an alternative ecosystem state with a more Pareto-efficient tradeoff frontier than the status-quo policy. A potentially reduced extinction risk for reef fish is plausible under this ecosystem-based policy option. This research provides a quantitative look at the fishery performance and ecological tradeoffs associated with various policy options. MSE methodology using ecosystem-based policy performance metrics is also demonstrated. Tool development and findings from this research should aid in the development of ecosystem-based policies for this region.

Nearly half of the population of the United States lives in coastal regions, and millions of visitors from across the nation and world enjoy the coasts every year. Coastal and marine areas provide for recreation, economic activities essential for the financial health of the nation, and vital ecological services. As they provide so many benefits to the U.S., it is vital to protect and preserve the coastal and ocean areas from the increasing, competing demands they are facing. In order to protect and preserve these complex systems, a comprehensive approach incorporating science, engineering, humanities, and social sciences should be taken; this approach is commonly referred to as Ecosystem-Based Management. This dissertation focuses on developing a framework that can be used to identify appropriate sub-regions in Northern Gulf of Mexico coastal and marine environments for the purposes of Ecosystem-Based Management. Through this work, the roles of three management protocols used for managing coastal areas – coastal and marine spatial planning, ecosystem-based management, and integrated ecosystem assessment – were examined individually as well as their integrations with each other. Biological, ecological, physical, human, and economic indicators for partitioning an ecosystem were developed and weighted for each management protocol using the analytic hierarchy process and expert elicitation. Using the weighted indicators, a framework for identifying sub-regions and estuarine classification system was developed. The framework and classification system were applied to five estuaries within the Northern Gulf of Mexico: Barataria, Galveston, Mobile, and Perdido Bays and Mississippi Sound. Initial results from this work show that: 1. Sub-regions can be identified as associated to each other based upon indicator data values and not upon physical location. 2. Even though the weights calculated for the management protocols vary significantly, for systems that were not highly homogeneous in indicator data values, the different weights did not produce the vastly different cluster maps expected. 3. The scale work indicates that to identify appropriate sub-regions using the developed framework, a larger grid size produces more consistent results for larger systems whereas a smaller grid size produces more consistent results for smaller systems. Recommendations for further research are also presented.