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Through an interpersonal global writing exchange between middle school students in Spain and the United States, students develop skills in world languages, cultural awareness, sensitivity, and communication. [ABSTRACT FROM AUTHOR]

Abstract: Fallout radionuclides (FRNs) and their ratios, such as Beryllium‐7 (7Be) and excess Lead‐210 (210Pbxs), have been used to determine suspended sediment source and age in catchments. These models are based on numerous assumptions, for example, that channel deposition of FRNs from precipitation is negligible in comparison to their delivery to the channel from land surface erosion during individual storm events. We test this assumption using a mass balance approach during eight storms from summer 2011 to fall 2012 in a mid‐Atlantic United States piedmont region watershed with mixed land use. Event peak discharge and storm type corresponded to the importance of direct channel FRN deposition from precipitation. During relatively low discharge summer thunderstorms, with minimal overland flow, less than 1% of 7Be and 210Pbxs flux deposited on the watershed exits the watershed associated with suspended sediment. The majority but not all deposited on the stream channel exits the watershed associated with suspended sediment (60% of 7Be and 80% of 210Pbxs). Here precipitation and throughfall onto the wetted channel area can be responsible for any FRN newly associated with suspended sediment, as opposed to landscape surface erosion. Furthermore, FRNs can be stored with sediments in the channel between events. Events with higher discharges, including hurricanes, show the opposite pattern—FRN flux associated with suspended sediment exported from the reach is greater than channel FRN wet deposition, suggesting net erosion from the watershed landscape and/or stored material during these types of storms. [ABSTRACT FROM AUTHOR]

In a post 9/11 world where large-scale violence against civilian populations is ever more being justified through fundamentalist interpretations of Sacred Scripture, it is a moral imperative that religious communities establish a basis for some kind of objective criteria to distinguish between legitimate and illegitimate interpretations of their sacred texts. While there has been much focus in the United States on the issue of Islamic extremism, the fact remains that Christian fundamentalism is a growing phenomenon behind US military aggression. However, Christian fundamentalism is not only an inadequate response to Islamic extremism, but more importantly it is dangerous because both ideologies share a presumption of their own righteousness and each divinely sanctions its acts of aggression toward the other. As an interpretive starting point, historical criticism becomes a much needed ‘prophetic voice of reason,’ whereby inspired texts are examined honestly and in light of the historical limitations they contain. A critical examination of biblical tradition, for example, will demonstrate that violence and cruelty are not tangential to biblical narratives, but intrinsic to them. Therefore, it is argued that the criteria to determine what is ethically demanded by the biblical texts must be sought in the future world toward which biblical narratives point, but in which they themselves do not fully participate. Only in this way can communities of faith begin to unmask the myth of their own righteousness and with it, the ambiguity that allows for the perpetration of untold violence and evil in the name of religion. [ABSTRACT FROM AUTHOR]

Presents a study which examined the ecological responses to the removal of a dam on lower Manatawny Creek in Pennsylvania. Design of Before-After-Control-Impact for Manatawny Creek dam removal; Biotic responses to dam removal within the former impoundment; Recommendations.

Compares the gravel-bed rivers in paired urban and rural catchments of southeastern Pennsylvania. Impact of urbanization on fluvial morphology and processes; Quantitative criteria for evaluating stream restoration projects in urban areas; Speculations on the supply of sediment to urban channels from hillslope processes and channel erosion.

Investigates the ontogeny of five flood plain segments along the Powder River in southeastern Montana. Analysis of flood-plain growth; Measurement of the cross-sectional profile of flood plains annually or biannually during low-flow conditions; Parameters for the discharge-stage relation used at five cross sections on the Powder River.

Quantifies the extent of autocompaction in a Holocene transgressive valley-fill deposit in Wolfe Glade, Delaware using a numerical model of compaction-driven ground-water flow and consolidation. Theory; Study area; Model structure and parameters; Ratios for summarizing extent of compaction.

Studies the response patterns of Powder River in Montana to variations in discharges with the use of data gathered through several years of annual surveys. Description of the study area; Discharge's impact on the balance between bank erosion and deposition.

Distinctive overbank sediments deposited since European settlement on the floodplain of the Brandywine Creek. Pennsylvania, are used to calibrate and test a diffusion model of overbank deposition. The predictions of the model can be calibrated to reproduce the topography of the post-settlement lithosome with an average error of 7%. The model also correctly predicts the decrease in mean grain size away from the channel. The model greatly underestimates the ability of floodwaters to transport sand away from the channel. Apparently, sand is transported across the floodplain by bedload transport and by advective suspended sediment transport as well as by diffusion. If flow duration data for 1912-1981 and the present rating curve for the Brandywine Creek at Chadds Ford, Pennsylvania, are assumed to apply throughout the post-settlement period, the model may be used to estimate palaehydraulic characteristics of post-settlement floods. Calculations indicate that 212 post-settlement floods covered the floodplain to an average depth of 1-6 m, transported an average excess suspended sediment concentration of 6200 ppm, and deposited an average thickness of 1-4 cm of sediment on levees next to the channel. [ABSTRACT FROM AUTHOR]

Abstract: The material exported from a watershed reflects its origin and the processes it undergoes during downhill and downstream transport. Due to its nature as a complex mixture of material, the composition of suspended particulate material (SPM) integrates the physical, biological and chemical processes effecting watershed material. This study will (1) use a sediment fingerprinting approach to quantify the composition and sources of SPM in the White Clay Creek Watershed in SE Pennsylvania and Delaware, USA, (2) examine longitudinal trends in SPM composition and source in first to fourth reaches of the White Clay Creek, (3) quantify the differences in composition and source with hydrologic variations produced by storms and seasonality. [Copyright &y& Elsevier]