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Many ecologically significant Midwestern rivers are heavily impacted by agri- culture yet retain high value for conservation of biodiversity. To address these concerns, watershed managers promote conservation practices (e.g., use of cover crops). Yet taking action to promote implementation of these practices in a cost-effective manner across a watershed is difficult because we rarely know where practices will be most effective, or how much of a benefit will accrue as the result of implementation of a given practice. To improve targeting of conservation practice implementation in locations most beneficial to biodiver- sity, we propose using a flexible approach assessing fields across a watershed for contributions towards ecological outcomes. We focused on Michigan's Paw Paw River Watershed, where key concerns for biodiversity include reduced infiltration and groundwater recharge that lead to pronounced low and high flow periods, and reduced water quality due to high sediment loads. We used outputs from several existing models to identify and prioritize the agricultural fields where conservation practices will have the greatest reduction in threats to biodiversity, including estimates of the input to groundwater and reduction in sedimentation. We tested the usefulness of our approach using four scenarios for implementation of six practices that vary in terms of the concentration of the practices in areas recommended by the models. Estimates of groundwater recharge under these scenarios were compared to recharge under simulated, "historic" placement scenarios based on USDA Natural Resources Conservation Service (NRCS) data for applied conservation practices in the same watershed. Collectively across the six practices, the prioritized scenarios provided an increase in groundwater recharge of between 23% and 36% over the historic scenario. Results for sediment reduction were more variable, but prioritized scenarios suggested a doubling of benefit can be obtained by focusing on agricultural lands predicted to contribute the highest sediment volumes. To maximize the benefits of aggregating practices, we identified subbasins of the watershed for direct outreach to landowners based on a ranking of potential, cumulative downstream conservation benefits and on opportunity factors. As a result of this process, prioritized areas and estimates of groundwater recharge are now informing implementation of conservation practices in the Paw Paw River Watershed, an approach applicable across the region.

Robeson Creek, located in Chatham County, North Carolina, is a 303 (d) listed stream due tochlorophyll a violations and impaired biological communities. Pollutants associated with thechlorophyll a violations are nutrient inputs from point and nonpoint sources within thewatershed. The North Carolina Division of Water Quality (DWQ) began monitoring waterquality of Robeson Creek and its tributaries in December 2000. DWQ has developed a TotalMaximum Daily Load (TMDL) for total phosphorus in this watershed. North Carolina StateUniversity (NCSU) in coordination with DWQ, the Robeson Creek Technical AdvisoryCommittee and other stakeholders in the watershed has developed a TMDL implementation planto address nonpoint sources of phosphorous in the Robeson Creek watershed. As part of theimplementation plan, NCSU performed a watershed assessment to refine identification ofpollutant types and sources as well as critical areas for implementing Best Management Practices(BMPs) at the subwatershed level. This paper will present an overview of the development process used for the TMDLimplementation plan for the Robeson Creek Watershed.

This work covers nitrogen containing organic chemicals, presenting easily retrievable data from the fields of physics and chemistry. The thermodynamic properties of fluids are vital information for design, operation (including safety considerations) and maintenance in the fluid processing or continuous manufacturing industries. Among the thermodynamic properties, some are more important and pervasive with vapor pressure being possibly the most important of all. Practical handling of any fluid requires knowledge of its vapor pressure, and vapor pressure (or boiling point) is invariably among the first properties measured for any substance.

Data on the densities of organic compounds are essential for both scientific and industrial applications. Knowledge of densities is important in many areas, including custody transfer of materials, product specification, development of various predictive methods, and for characterizing compounds and estimating their purity. The densities of polycyclic hydrocarbons were collected from the original literature published from 1870 to early 1998 and critically evaluated. The tables contain the original literature data along with their estimated uncertainties, and the evaluated data, in both numerical form and as coefficients to equations with selected statistical information. The volume also contains the CASR Number Index, a Chemical Name Index and a CD-ROM which allows fast full text index search.

Tabulated data on density alkylbenzenes (CnH2n 6) tabulated data on density alkenylbenzenes (CnH2n 8) tabulated data on density alkynylbenzenes, alkadienylbenzenes, and dialkenylbenzenes (CnH2n 10) tabulated data on density unsaturated alkylbenzenes (CnH2n 12) tabulated data on density unsaturated alkylbenzenes (CnH2n 14) Chemical Abstracts Service Registry Number (CASRN) index.

Tabulated data on density - alkylcycloalkanes (CnH2n) tabulated data on density - alkylcycloalkanes and alkenylcycloaklkanes (CnH2n-2) tabulated data on density - monocyclic hydrocarbons (CnH2n-4) tabulated data on density - monocyclic hydrocarbons (C2H2n-6) tabulated data on densities - monocyclic hydrocarbons (CnH2n-8).