A MATHEMATICAL MODEL FOR DEVELOPING ETHNO-BIOLOGICALLY DIVERSE TROPICAL FORESTS

This paper presents a dynamic optimal control model describing the benefits and costs associated with the development of tropical forests rich in plant and animal species and folk knowledge. The model is a framework to assess how various market and institutional incentives might influence both deforestation and the collection of "ethno-biological information."Resource /Energy Economics and Policy,

MARINE RESERVES FOR FISHERIES MANAGEMENT

Conventional methods of regulating commercial fisheries restrict catch by limiting either the quantity or efficiency of fishing effort, or by putting direct limits on catch. These regulatory practices are neither feasible nor desirable for many fisheries, and have failed to conserve fishery stocks in other fisheries. Marine reserves may be an effective alternative management strategy for some fisheries. Here we develop a dynamic model of marine reserves applicable to inshore fisheries. In contrast to previous models of reserves, the model is fully dynamic and provides information on both equilibrium conditions and the path to equilibrium. A simulation model based on red snapper data from the Gulf of Mexico is presented. The simulation results suggest that marine reserves can sustain or increase yields for moderate to heavily fished fisheries but will probably not improve yields for lightly fished fisheries.Resource /Energy Economics and Policy,

Determinants of Newspaper Circulation

This study offers a new approach to the problem of time-series studies and attempts to set up a model to account for the growth in demand for daily newspapers Using U S data on a state-by-state basis for 1850 to 1970, we have used a marketing approach What conditions were necessary for the survival of a daily newspaper? What conditions were conducive to consolidation? What conditions were a barrier to the adoption of social and technological innovation? The data were grouped into geographic and social regions for analysis, using a special case of generalized least squares Independent variables included price as a proportion of per-capita income, percentage of the work force in nonagricultural labor, education, voting, and urbanization. Price proved the most powerful predictor Corrected R2s range from 22636 (m regions where newspaper growth took place very early or late in the period) to 67543 in the Midwest and Southwest The model will be applied to data from the industrialized countries of Western Europe in later workPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67057/2/10.1177_009365028000700101.pd

Inland Pacific Northwest pasture calendar

The Inland Pacific Northwest (PNW) region, historically referred to as the 'Inland Empire', extends from the Cascade Mountains in the west to former Glacial Lake Missoula in the Rockies in the east and from the Canadian border in the north past the Snake River Canyon in the south. The greatest agricultural enterprises are hay (from various forage species), irrigated and non-irrigated grassland pastures, rangelands, and livestock production. It is also home to numerous wildlife species and flyways for migrating birds. The Inland PNW Pasture Calendar is designed to be a comprehensive guide for improved grassland management in support of forage-livestock systems. Applying the principles described will lead to improved regional economic, ecological, and social sustainability. This publication describes the opportunities and challenges of sustainably raising harvested and grazed forages and developing forage-livestock systems in this incredibly diverse environment. Appendix Chapters provide key information on grass / legume / forb species, how pasture species grow and regrow, soil nutrient management and organic matter, grazing philosophies and systems, matching grazing needs for pasture production, and forage-related animal health issues. Learning these key principles and following best management practices described will lead to improved sustainability of forage-livestock systems

Fruit crops: a summary of research, 1998

Pesticide deposition in orchards: effects of pesticide type, tree canopy, timing, cultivar, and leaf type / Franklin R. Hall, Jane A. Cooper, and David C. Ferree -- The influence of a synthetic foraging attractant, Bee-Scent™, on the number of honey bees visiting apple blossoms and on subsequent fruit production / James E. Tew and David C. Ferree -- The reliability of three traps vs. a single trap for determining population levels of codling moth in commercial northern Ohio apple orchards / Ted W. Gastier -- Evaluation of an empirical model for predicting sooty blotch and flyspeck of apples in Ohio / Michael A. Ellis, Laurence V. Madden, and L. Lee Wilson -- Influence of pesticides and water stress on photosynthesis and transpiration of apple / David C. Ferree, Franklin R. Hall, Charles R. Krause, Bruce R. Roberts, and Ross D. Brazee -- Influence of temporary bending and heading on branch development and flowering of vigorous young apple trees / David C. Ferree and John C. Schmid -- The effect of apple fruit bruising on total returns / Richard C. Funt, Ewen A. Cameron, and Nigel H. Banks -- Yield, berry quality, and economics of mechanical berry harvest in Ohio / Richard C. Funt, Thomas E. Wall, and Joseph C. Scheerens -- Monitoring flower thrips activities in strawberry fields at two Ohio locations / Roger N. Williams, M. Sean Ellis, Dan S. Fickle, and Carl M. Pelland -- Cluster thinning effects on fruit weight, juice quality, and fruit skin characteristics in 'Reliance' grapes / Yu Gao and Garth A. Cahoon -- Effects of various fungicide programs on powdery mildew control, percent berry sugar, yield, and vine vigor of 'Concord' grapes in Ohio / Michael A. Ellis, Laurence V. Madden, L. Lee Wilson, and Gregory R. Johns -- Influence of growth regulators, cropping, and number on replacement trunks of winter-injured 'Vidal Blanc' grapes / David C. Ferree, David M. Scurlock, and Rick Evans -- Effect of new herbicides on tissue-cultured black raspberry plants / Richard C. Funt, Thomas E. Wall, and B. Dale Stokes -- Investigating the relationship between vine vigor and berry set of field-grown 'Seyval Blanc' grapevines / Steven J. McArtney and David C. Ferree -- Summary of Ohio Fruit Growers Society apple cider competition, 1993-1997 / Winston Bash and Diane Mille

The Non-Timber Service Value of Old Growth Forests: The Management of U.S. national forests in Western Washington

Over the past few decades the management of public old growth forest in the United States has been the focus of public debate. The tradeoffs between timber harvesting and amenity benefits of standing forests have been a key issue in this debate with national forest managers critiqued for both harvesting old growth forests too slowly or too quickly. To date there has been little analysis of the actual values placed on amenity benefits of old growth on national forests. The objective of this study is to analyze old growth forest management on U.S. national forests including the implicit amenity values of national forest managers. Using a data set from western Washington we estimate the implicit values of non-timber services by U.S. national forest managers. The average non-timber service changes during the study period, and increases as the stock of old growth forest decreases. The estimated value of per acre non-timber services is considerably higher than the values from previous studies. The results also suggest that national forest managers have at least partially recognized the non-timber benefits of old growth forests

Sustainibility and Long-term Dynamics of Forests: Methods and Metrics for Detection of Convergence and Stationarity

Sustainability has several definitions within natural resource economics. Sustainable states may be economically or biologically determined. Age and age classes add complexity to any definition of forest sustainability. Here we focus on selected metrics that might be used to define forest sustainability, convergence to sustainable state, and methods that allow convergence detection and classification of forest dynamics. In a deterministic world sustainable states of forests may be cyclic or fixed. If random perturbations are included, sustainability is associated with convergence of distribution parameters. Pattern recognition procedures are presented that detect whether a forest converges to a cyclic, a fixed or stationary state and whether convergence is fast, slow or cannot be observed within the time horizon considered

A MATHEMATICAL MODEL FOR DEVELOPING ETHNO-BIOLOGICALLY DIVERSE TROPICAL FORESTS

This paper presents a dynamic optimal control model describing the benefits and costs associated with the development of tropical forests rich in plant and animal species and folk knowledge. The model is a framework to assess how various market and institutional incentives might influence both deforestation and the collection of "ethno-biological information.