Linkages between unpaved forest roads and streambed sediment: why context matters in directing road restoration

Unpaved forest roads remain a pervasive disturbance on public lands and mitigating sediment from road networks remains a priority for management agencies. Restoring roaded landscapes is becoming increasingly important for many native coldwater fishes that disproportionately rely on public lands for persistence. However, effectively targeting restoration opportunities requires a comprehensive understanding of the effects of roads across different ecosystems. Here, we combine a review and a field study to evaluate the status of knowledge supporting the conceptual framework linking unpaved forest roads with streambed sediment. Through our review, we specifically focused on those studies linking measures of the density of forest roads or sediment delivery with empirical streambed sediment measures. Our field study provides an example of a targeted effort of linking spatially explicit estimates of sediment production with measures of streambed sediment. Surprisingly, our review uncovered few studies (n = 8) that empirically tested the conceptual framework linking unpaved forest roads and streambed sediment, and the results varied considerably. Field results generally supported the conceptual model that unpaved forest roads can control streambed sediment quality, but demonstrated high‐spatial variability in the effects of forest roads on streambed sediment and the need to address hotspots of sediment sources. The importance of context in the effects of forest roads is apparent in both our review and field data, suggesting the need for in situ studies to avoid misdirected restoration actions.     

Tracing neuronal connections with radioisotopes applied extracellularly.

Methodological and technical problems of the autoradiographic-neuroanatomical tracing (ARNT) technique are discussed. The size of the labeled area after a tritiated amino acid injection varies directly with the volume of isotope, the rate of injection, and the length of exposure of the secretion to the emulsion. Frozen sections can be used for autoradiography if they are mounted on subbed slides, dehydrated in ethanol, defatted for 1 hour in xylene, rehydrated through ethanol and water, and dried before coating with emulsion. Brushes used for mounting frozen sections should be used only for this purpose and dipped in boiling distilled water before use to avoid chemoreduced streaks in the emulsion due to contamination from the brushes. Excessive dilution of Kodak emulsion can leave less than a monolayer of grains over certain types of sections; the emulsion thickness should be checked by exposing coated test sections to a brief flash of light and developing immediately. A high intensity safelight recommended for the ARNT darkroom is the Thomas Duplex Super monochromatic sodium vapor bulb safelight; for Kodak NTB-2, -3 and Ilford L4 emulsions the red-banded and yellow-banded filters are used. A useful stain combination for ARNT is Luxol fast blue stained before coating and cresyl violet stained after developing which demonstrates both neuronal cell bodies and myelinated tracts in the same section.     

Clean Recycling of Lead-Acid Batteries for Electric Vehicles: A Reply to Socolow and Thomas

This article is stimulated by the analysis of Socolow and Thomas in the first issue of this journal. Our work showed that a lead-acid battery-powered electric vehicle (Ev) would result in more lead being discharged into the environment than a comparable car burning leaded gasoline. Five hundred thousand EVs would lead to a 20% increase in lead use in the United States, and presumably a comparable 20% increase in lead discharges.
The Socolow-Thomas analysis asserts: (I) choosing not to pursue technology that uses toxic materials will unduly constrain the research and development (R&D) in advanced vehicles and limit the options likely to emerge from that research; (2) we do not do a full risk assessment of the lead discharges from lead smelting, battery making and recycling; and (3) in response to regulation the industry might devise a "clean recycling" system.
We doubt the wisdom of increasing R&D on lead batteries because introducing large quantities of lead into cars will pose health risks. The possibility of clean recycling in the future is not an adequate basis for mandating EVs. Proponents of EVs should prove there is no harm to the environment Regulators should not require EVs until there is a reasonable showing of environmental benefit and that the requirement is cost-effective in reducing ozone.