The Wyoming Survey for Hα, or WySH, is a large-area, ground-based imaging survey for Hα-emitting galaxies at redshifts of z ≈ 0.16, 0.24, 0.32, and 0.40. The survey spans up to four square degrees in a set of fields of low Galactic cirrus emission, using twin narrowband filters at each epoch for improved stellar continuum subtraction. Hα luminosity functions are presented for each ∆z ≈ 0.02 epoch based on a total of nearly 1200 galaxies. These data clearly show an evolution with lookback time in the volume-averaged cosmic star formation rate. Integrals of Schechter fits to the incompleteness-and extinction-corrected Hα luminosity functions indicate star formation rates per co-moving volume of 0.010, 0.013, 0.020, 0.022 h 70 M ⊙ yr −1 Mpc −3 at z ∼ 0.16, 0.24, 0.32, and 0.40, respectively. Statistical and systematic measurement uncertainties combined are on the order of 25% while the effects of cosmic variance are at the 20% level. The bulk of this evolution is driven by changes in the characteristic luminosity L * of the Hα luminosity functions, with L * for the earlier two epochs being a factor of two larger than L * at the latter two epochs; it is more difficult with this data set to decipher systematic evolutionary differences in the luminosity function amplitude and faint-end slope. Coupling these results with a comprehensive compilation of results from the literature on emission line surveys, the evolution in the cosmic star formation rate density over 0 z 1.5 is measured to bė ρ SFR (z) =ρ SFR (0)(1 + z) 3.4±0.4 .

A key factor determining the potential for development of cellulosic bioenergy in the southeastern United States (the South) will be the availability of feedstock, which in turn depends on landowner willingness to direct timber production to biomass rather than existing markets or nonmarket uses. Most timberland in this region is owned by family forest landowners whose forest management objectives are varied. This study evaluates the conditions under which family forest landowners from Lee County, Alabama, would be willing to supply wood biomass energy feedstock for a prospective local biofuel industry. Using standard survey methodology, a questionnaire was mailed to every family forest landowner of 20 or more acres of forestland in Lee County, resulting in 363 valid responses and a response rate of 41%. Results indicate that most family forest landowners are willing to supply both timber and harvest residues for production of biofuels and that such willingness is positively correlated with the number of acres owned, the existence of an effective market, and the opportunity to contribute to local economic development and global climate change. Three-quarters of all respondents indicated willingness to manage their land for biomass production, compared with 43% of respondents who actively manage their land at present.

The specifications for this study were set by the need for researchers in the Sustainable Grazing Systems (SGS) Program to have a consistent framework to evaluate experimental results across research sites and to share those results in a comprehensive way with livestock producers, allowing them to consider the full range of outcomes and impacts. To achieve this, the framework needed to account for production, economic and natural resource impacts, and other issues associated with making changes on farms. It also had to be easily applied, and readily understood by all segments of the SGS Program. This approach demanded some elements of pragmatism.Economic analysis of production data was based around net cash flow analysis. Spreadsheet programs were written for beef, self-replacing Merino and prime lamb enterprises. These incorporated the capacity to graph results automatically, provide sensitivity analysis tables, and project net cash flow results averaged over a 10-year period. Net cash flows were given for 2 levels of management skills -'district average' and 'high'.Placing dollar values or costs on resource impacts was not as simple and could not be achieved within the practical framework required. A qualitative approach to the evaluation of resource impacts was developed in collaboration with researchers, advisors and collaborating producers. A framework was constructed which allows the likely on-and off-farm impacts of any experimental treatments to be identified and subjectively rated for likely importance.A practical tool for integrating and reporting the production and resource impact information was constructed. This captures the net cash flow, the key production data, the off-farm and on-farm impacts and provides an overview assessment of the treatment in a simple table. It provides producers with sufficient information to allow an assessment as to whether adoption of any 'treatment' could improve the profitability and sustainability of their grazing system. This tool was tested across all treatments at the SGS National Experiment sites and found to work well. Examples are presented, covering a range of resource impact and net cash flow combinations.

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Although numerous and varied users harvest, trade, and consume nontimber forest products (NTFPs), relatively little is known about the organization of the markets for these products and the market value or contribution to local and regional economies. In this article, we review and synthesize economic research and information on the markets and market values of NTFPs in the United States. We describe formal and informal markets for NTFPs, and the extent to which and reasons why many of the details of these markets remain unknown to researchers and decisionmakers. We provide examples of the market values of various species and identify information gaps and research needs to improve resource management and increase economic development.

Nonmarketed forest outputs need to be quantitatively measured and valued to project monetary gains and losses associated with varying these outputs relative to timber production. Of particular importance to many landowners is the quantity and value of timber production forgone relative to the creation or maintenance of wildlife habitat. We used scenario planning and a geographic information system to estimate potential monetary gains or losses for the North Central Hills region in Mississippi by manipulating timber growing stock to produce more or less habitat for northern bobwhite (Colinus virginianus), white-tailed deer (Odocoileus virginianus), and eastern wild turkey (Meleagris gallopavo silvestris). As expected, timber management–only scenarios, which maximized net present value (NPV), produced higher equivalent annual income values per hectare and allocated fewer habitat hectares for all wildlife species versus managing for wildlife habitat quality. Inclusion of fee hunting reduced cost differences between NPV only and improved wildlife habitat management scenarios. Simulations comparing management regimes maximizing NPV and optimizing wildlife habitat resulted in quantitative measures, which will be useful for land managers evaluating tradeoffs inherent in multiple-use management.

En los últimos veinte años, la industria de productos forestales vendió gran parte de sus tierras en los Estados Unidos, incluyendo aproximadamente 18 millones de hectáreas en el sur de los Estados Unidos. Las decisiones de gestión de los nuevos propietarios repercutirán directamente en la sociedad, la economía y la ecología locales. Las investigaciones previas se han enfocado en tendencias generales, sin prestar atención al impacto local que este evento tendrá en las comunidades rurales que dependen de la madera. Este estudio hace un mapa del cambio de propiedad de las tierras madereras en cinco condados del suroeste de Alabama donde se concentra la producción de madera. Para identificar dónde la tierra cambió de dueño, se comparó la propiedad maderera industrial de principios de los noventa con la propiedad actual de la tierra. Siguiendo las tendencias nacionales, la mayoría de esos terrenos (63%) pertenece a corporaciones madereras con propietarios ausentes. Aunque el cambio de propietarios ha dejado el bosque aparentemente intacto con poca fragmentación o cambio de uso, han ocurrido algunos cambios de importancia ecológica como la compra de 54.000 hectáreas para la conservación. Este trabajo analizará las implicaciones de estos cambios.

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