A pollen identification expert system ; an application of expert system techniques to biological identification : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Computer Science Massey University

The application of expert systems techniques to biological identification has been investigated and a system developed which assists a user to identify and count air-borne pollen grains. The present system uses a modified taxonomic data matrix as the structure for the knowledge base. This allows domain experts to easily assess and modify the knowledge using a familiar data structure. The data structure can be easily converted to rules or a simple frame-based structure if required for other applications. A method of ranking the importance of characters for identifying each taxon has been developed which assists the system to quickly narrow an identification by rejecting or accepting candidate taxa. This method is very similar to that used by domain experts

Anthropogenic and Natural Determinants of the Population of a Sensitive Species: Sage Grouse in Nevada

This paper uses Nevada data to conduct regression analyses of the relationship between sage grouse (Centrocercus urophasianus) population sizes and potential causal factors. This is policy-relevant because of current petitions for listing this species under the Endangered Species Act. A key feature is that, although monitoring of sage grouse has occurred for many decades, data collection methods and level of monitoring effort have not been consistent. To account for this feature we use, as dependent variables, standardized measures such as population counts and harvest (hunting success) per unit of effort. Preliminary findings suggest that such measures have been particularly sensitive to whether or not humans used strychnine for predator control, with normalized measures of grouse populations higher in years when strychnine was employed. Our results also suggest a positive association between the number of cattle on the range and normalized measures of grouse population. This is a controversial finding as some studies suggest a negative impact of cattle grazing on grouse. Our data do not include indications of the timing and precise nature of grazing practices and so should be interpreted with caution.population viability analysis and endangered species, factors affecting decline of sage grouse

Niche and Direct Marketing in the Rural-Urban Fringe: Study of the Agricultural Economy in the Shadow of a Large City

Farmers in the rural-urban fringe (RUF) face unique challenges. Spillovers from the urban region and competition for land increase the costs of farming relative to farming farther removed. Yet, there is greater potential for off-farm employment and niche marketing of farm products, providing more income options to RUF farmers. In this research, we employ a survey of direct- and niche-marketing farmers located in the RUF of Vancouver, Canada to examine how the rural-urban interface affects farms, particularly their long-term survivability and sustainability. From a list of 102 direct marketing and organic farmers, we managed to elicit twenty-nine completed surveys. Annual gross farm receipts averaged almost $500,000, similar to the census average for all farms in the region. Incomes varied significantly among respondents and farmers produced a wide range of products, and yet exhibiting a willingness to invest in their farms. Respondents had been farming for an average over twenty years and are highly educated. Compared with farmers near Victoria, on Vancouver Island, producers who use direct marketing or organic methods in the Vancouver RUF have higher gross farm incomes, rely less on off-farm income and are much more likely to carry farm debt. Direct marketing also contributes to total farm sales, with only 19.5% of product value marketed at the farm-gate, at farmers’ markets or through delivery programs, compared to 57.3% of farms near Victoria. Wholesalers, distributors and processors play a larger role on the mainland, likely because the amount of farm product available makes operation of such facilities economically feasible.Direct marketing, organic farming, niche marketing, agritourism, local agriculture, farm survival

Optimal Forest Strategies for Addressing Tradeoffs and Uncertainty in Economic Development under Old-Growth Constraints

In Canada, governments have historically promoted economic development in rural regions by promoting exploitation of natural resources, particularly forests. Forest resources are an economic development driver in many of the more than 80% of native communities located in forest regions. But forests also provide aboriginal people with cultural and spiritual values, and non-timber forest amenities (e.g., biodiversity, wildlife harvests for meat and fur, etc.), that are incompatible with timber exploitation. Some cultural and other amenities can only be satisfied by maintaining a certain amount of timber in an old-growth state. In that case, resource constraints might be too onerous to satisfy development needs. We employ compromise programming and fuzzy programming to identify forest management strategies that best compromise between development and other objectives, applying our models to an aboriginal community in northern Alberta. In addition to describing how mathematical programming techniques can be applied to regional development and forest management, we conclude from the analysis that no management strategy is able to satisfy all of the technical, environmental and social/cultural constraints and, at the same time, offer aboriginal peoples forest-based economic development. Nonetheless, we demonstrate that extant forest management policies can be improved upon.forest-dependent aboriginal communities, boreal forest, compromise and fuzzy programming, sustainability and uncertainty, International Development, Resource /Energy Economics and Policy, R11, Q23, Q01, C61,

Social Dilemmas and Public Range Management: Results from the Nevada Ranch Survey

Since the late 1960s, the Nevada ranch community has come under increasing pressure from environmental groups regarding their use of public lands for livestock grazing, thus increasing tension between ranchers and public land managers and potentially reducing the social capital that facilitates action and cooperation in range management. In this paper, we use responses to a survey of all public grazing permit holders in Nevada to investigate the changing relationships between ranchers and the public land agencies, and its potential implications. In particular, we investigate factors that affect ranchers’ trust in the public land agencies, and then factors that influence the nature of the relationship between ranchers and the Bureau of Land Management and U.S. Forest Service. Low levels of trust between ranchers and public managers were most significantly related to previous disagreements and the belief in a poor future for ranching. The occurrence of wildfire on grazing land contributed most signifcantly to increased disagreement between ranchers and public agencies. Finally, as a response to conflict in the ranch community, community based initiatives, such as grass banking, are examined for their potential to bring stakeholders together to realize and address common goals. Community involvement in decision making may increase levels of social capital, reduce transaction costs, and thus allow for more effective and efficient use of the range resources.Institutions and social capital, effectiveness of range management policies

How Costly are Carbon Offsets? A Meta-Analysis of Forest Carbon Sinks

Carbon terrestrial sinks are seen as a low-cost alternative to fuel switching and reduced fossil fuel use for lowering atmospheric CO2. As a result of agreements reached at Bonn and Marrakech, carbon offsets have taken on much greater importance in meeting Kyoto targets for the first commitment period. In this study, meta-regression analysis is used to examine 981 estimates from 55 studies of the costs of creating carbon offsets using forestry. Baseline estimates of costs of sequestering carbon through forest conservation are US$46.62–$260.29 per tC ($12.71–$70.99 per t CO2). Tree planting and agroforestry activities increase costs by more than 200%. When post-harvest storage of carbon in wood products, or substitution of biomass for fossil fuels in energy production, are taken into account, costs are lowest – some $12.53/tC to$68.44/tC ($3.42–$18.67/t CO2). Average costs are greater, between $116.76 and$1406.60/tC ($31.84–$383.62/t CO2), when appropriate account is taken of the opportunity costs of land. Peer review of the studies increases costs by a factor or 10 or more, depending on the model. The use of marginal cost estimates instead of average cost results in much higher costs for carbon sequestration, in the range of thousands of dollars per tC, although few studies used this method of cost assessment.climate change; Kyoto Protocol, meta-regression analysis, carbon-uptake costs, forest sinks

Hobby Farms and British Columbia’s Agricultural Land Reserve

Agricultural land protection near the urban-rural fringe is a goal of many jurisdictions, including British Columbia, Canada, which uses a provincial-wide zoning scheme to prevent subdivisions and non-agricultural uses of the land. Preferential taxes are also used to encourage agricultural use of the land. Small scale hobby farmers are present at the urban fringe near Victoria (the capital), both inside and outside of the Agricultural Land Reserve (ALR). The goal of this paper is to investigate whether hobby farms create problems for agricultural land preservation. We make use of a GIS (geographic information system) model to construct detailed spatial variables and analyse our parcel-level data set using an hedonic pricing model and a limited dependent variable model. The results show that hobby farmers tend to select small parcels that are near open space and relatively close to the city and they tend to support horses and other livestock. In terms of price, farmland is worth more per ha the smaller the parcel is and the closer it is to the city. In general farmland is worth more when it is less fragmented but this appears to be reversed for hobby farms – indicating that hobby farmers may be better adapted to surviving in the urban fringe than conventional farmers. The conclusions drawn from the results in this paper would likely apply to other jurisdictions which seek to protect agricultural land in the urban fringe.Hobby farmers, Agricultural Land Reserve, Geographical Information System, urban-rural fringe, zoning systems, farmland fragmentation

Dynamic Programming and Learning Models for Management of a Nonnative Species

Nonnative invasive species result in sizeable economic damages and expensive control costs. Because dynamic optimization models break down if controls depend in complex ways on past controls, non-uniform or scale-dependent spatial attributes, etc., decision support systems that allow learning may be preferred. We compare three models of an invasive weed in California’s grazing lands: (1) a stochastic dynamic programming model, (2) a reinforcement-based, experience-weighted attraction (EWA) learning model, and (3) an EWA model that also includes stochastic forage growth and penalties for repeated application of environmentally harmful control techniques. Results indicate that EWA learning models may be appropriate for invasive species management.Invasive weed species, optimal control, adaptive management

Economic Impacts of Yellow Starthistle on California Ranchers

While the significant ecosystem damage caused by invasive weeds has been well documented, the economic impacts of specific invasive weed species are poorly understood. Yellow starthistle (Centaurea solstitialis L., hereafter YST) is the most widespread non-crop weed in California, resulting in serious damage to forage on natural range and improved pasture. A survey was administered to California cattle ranchers to investigate YST infestation rates, loss of forage quantity and value, and control or eradication efforts. The results were used to estimate county-wide economic losses for three focus counties, as well as state-wide economic losses, due to YST in California. Total losses of livestock forage value due to YST on private land for the state of California are estimated at $7.96 million/year, with ranchers’ out-of-pocket expenditures on YST control amounting to$9.45 million/year. Together, these costs are the equivalent of 6-7% of the total annual harvested pasture value for the state. Therefore, while the impacts are relatively small within the statewide total agricultural production system, costs due to YST infestation significantly constrain California’s livestock grazing sector.nonnative species, invasive weeds, yellow starthistle, ranching profitability, forage, livestock