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The Atchafalaya River Basin is the largest remaining forested wetland in the contiguous United States. Since 1960, dredging and channel erosion in the Basin have resulted in changes to the hydrologic connectivity that have not been quantified. Analyses were conducted to determine the hydraulic and geomorphic factors that have changed since discharge became controlled that may have decreased river/floodplain connectivity. We examined: (1) stage/discharge relationships from 1960 to 2014; (2) hydroperiods across the floodplain; (3) discharge distribution to the floodplain by comparing discharge measurements from 1959–1968 to 2005–2012; and (4) channel cross‐sections and floodplain elevations. Our results indicate that much of the floodplain no longer receives headwater discharge (upstream to downstream, > 200 km2) or receives too little discharge to alleviate stagnancy and hypoxia in the forested wetland at lower stages. Large portions of the Basin (400 km2) have low water levels controlled by channel geomorphology and sea‐level rise that inundate the forested floodplain for more than 50% of the calendar year. This extended duration of inundation contributes to hypoxia and likely reduces nutrient retention. The confinement of discharge to a large efficient channel compromises the ability of this system to respond to sea‐level rise and subsidence. This study provides insight to the effects of flood management projects along Coastal Plain rivers and deltas. [ABSTRACT FROM AUTHOR]

Model-based water quality assessments are an important informer of conservation and environmental policy in the U.S. The recently completed national scale Conservation Effects Assessment Project (CEAP) is being replicated using an improved model populated with new and higher resolution data. National assessments are particularly difficult as models must operate with both a very large spatial extent (the contiguous U.S.) while maintaining a level of granularity required to capture important small scale processes. In this research, we developed datasets to describe the hydrologic connectivity at the U.S. Geological Survey (USGS) 12-digit Hydrologic Unit Code (HUC-12) level. Connectivity between 86,000 HUC-12s as provided by the Watershed Boundary Dataset (WBD) was evaluated and corrected. We also detailed a method to resolve the highly detailed National Hydrography Dataset (NHD) stream segments within each HUC-12 into vastly simplified representative channel schemes suitable for use in the recently developed Soil andWater Assessment Tool + (SWAT+) model. This representative channel approach strikes a balance between computational complexity and accurate representation of the hydrologic system. These data will be tested in the upcoming CEAP II national assessment. Until then, all the WBD corrections and NHDPlus representative channel data are provided via the web for other researchers to evaluate and utilize. [ABSTRACT FROM AUTHOR]

As the complexity of a system grows, the challenge of informing the stakeholders of that system grows correspondingly. Nowhere is that challenge more daunting than in business education, where globalization, technological innovation, and increasingly complicated regulations continuously transform the business environment facing graduates and practitioners. Informing science theory proposes that different levels of complexity require different channels if effective informing is to be achieved. The paper first examines how two important sources of complexity--the diversity of clients and the ruggedness of the business landscape--are changing, and how these changes demand vastly more interactive informing channels if impact is to be achieved. Using an exploratory case study methodology, it then takes a detailed look at how one institution--the University of South Florida's Muma College of Business--has introduced a variety of new channels, many of which enable informing flows without necessarily directing them, to adapt to these environmental changes. It then considers both outcomes related to these individual informing channels and college-wide outcomes related to a broad and deep mosaic of informing flows. Finally, it considers the question of the resources required to support these new channels and the relationship between resource acquisition and channel introduction. The proposed framework for looking at business school informing channels can be applied by administrators, faculty members, and key stakeholders in understanding, evaluating, and planning programs and activities supporting informing in a complex environment. Ultimately, the informing business school framework may also provide a means for communicating impact to business school accrediting agencies (such as AACSB). [ABSTRACT FROM AUTHOR]

Abstract: This paper presents data compiled from aerial photography, General Land Office maps (GLOs), and discharge data from the central Platte River in Nebraska that quantify and provide a new understanding of channel evolution and abandonment in a braided stream. Analyses of aerial photographs and GLOs in ArcMap™ show that channel area decreased by an average of 46% from 1938 to 2006 and that channel widths in 1858 were an average of 539% greater than in 2006. Annual discharge during 1942–2006 does not show a clear long-term relationship with the decrease in channel width and area. Rather, stabilization through vegetation of bars and channel banks is cited as the major contributing factor to channel shrinkage and the development of an anabranching system within the boundaries of the 1858 channel. The stabilization of anabranches and the encroachment of vegetation onto banks, abandoned channels, and islands have significantly impacted the riparian ecosystem as mobile sandy bars gradually disappeared. Annual aerial photographs of the Platte River from 1984 to 2001 show that the river responds to year-to-year changes in mean discharge through the formation and disappearance of in-channel features such as medium-size transverse bars, large transverse bars, open channels, exposed channel surfaces, laterally accreted surfaces, and vegetated channel islands. Vegetated channel islands and stable anabranches also increased during 1984–2009. Significant change has also occurred since the beginning of the twentieth century on the Wood River, a local tributary to the Platte River. The Wood River experienced a long-term increase in sinuosity after it occupied the abandoned North Channel of the Platte River, which last experienced major sediment transport 350±50years ago, according to an optically stimulated luminescence date. The modern Wood River is also superimposed on a prehistoric meandering pattern with significantly greater meander amplitude. We present the first channel abandonment model to account for the gradual abandonment of the Platte River braided stream system and its evolution from a braided to an anabranching system: in stage 1, the channel prominently features macroform bars comprising downstream-migrating foresets; in stage 2, downstream-migrating dunes are deposited over channel bed features; and in stage 3, there is a shift from a braided stream to a stream dominated by anabranches and only channel bed features (e.g., three-dimensional dunes) are present. Our new model characterizes the features expected to be found in abandoned braided channels, as well as more temporary features that form and are destroyed through successive stages of abandonment. [Copyright &y& Elsevier]

BML monitors consumer book purchases in Britain via its Books & Consumers survey. RR Bowker tracks US consumer book purchases via its PubTrack Consumer survey. This report compares the results of the two surveys. In 2008, the US consumer market was around ten times the size of its UK equivalent, but a higher proportion of British than US consumers bought books. Book buyers in each country were similar in terms of gender and age, but slightly more ‘up market’ in the US than Britain. Adult fiction and hardbacks accounted for a higher proportion of book purchases in the US than in Britain, but with variations in the mix of genres bought. Chain bookshops remained the largest channel for book purchases in Britain, despite losing share in recent years. The internet overtook the chains in the US in 2008, with Britain around 3 years behind in terms of internet share. [ABSTRACT FROM AUTHOR]

Abstract: Holocene colluvial and alluvial stratigraphy and a radiocarbon chronology are presented for the valley of the lower three kilometers of Raven Fork, a mountain stream draining 194 km2 of high relief (1.3 km) terrain of the Southern Blue Ridge Mountains in western North Carolina, USA, which is in a region that lacks good chronological data. Lower hillslopes, alluvial/colluvial fans, alluvial bottomlands (first terrace and floodplain), and the modern stream channel are landforms described with respect to soils, stratigraphy, and sedimentary structures. Standard methods for subsurface investigations (core holes, excavation units, exposures) are used in conjunction with extensive archeological excavations and cultural chronologies. Radiocarbon ages from each landform are used to calculate long-term-average rates of sedimentation. Results indicate that the first half of the Holocene experienced somewhat more rapid rates of hillslope sedimentation (0.3 to 1.1 mm/yr) than the last half of the Holocene (0.1–0.2 mm/yr) on footslopes, toeslopes, and alluvial/colluvial fans prior to historic time. We suggest that these subtle differences in the rates of sedimentation were driven by changes in global paleoclimate that favored a high frequency of heavy rainfall, including tropical storms and/or severe thunderstorms and more (and possibly larger) floods during the first half of the Holocene. Prehistoric rates of vertical accretion on the first terrace (T1) ranged from 0.1 to 0.8 mm/yr between about 10,000 and 3000 calendar years ago, and incision below T1 formed the late Holocene floodplain beginning at about 6000 years ago. We suggest that this incision is linked to a reduction in the supply of sediment and a reduction in the magnitude of floods. Historical rates of sedimentation on all parts of the depositional landscape (2.0–2.7 mm/yr on hillslopes and fans and 5.8–6.5 mm/yr on floodplains) were about an order of magnitude greater than prehistoric rates. We attribute these rates to human impacts, such as timber harvest and land clearing, which caused accelerated erosion. We attribute the abundance of fine-grained sediment in streams of the Southern Blue Ridge province, which is atypical in many mountain streams around the world, to the regionally widespread mantle of saprolite as a source of sediment to the fluvial system. Holocene sedimentation on all depositional landforms in the valley led to sedimentary burial of archeological materials, which highlights the need to consider site burial on lower hillslopes and terraces for evaluation of the cultural resources in the Southern Blue Ridge Mountains. These findings show that the entrenched condition of the Raven Fork channel was inherited from the middle Holocene and can be considered a “natural” state for this mountain stream, casting doubt on the negative connotation that is often assigned to entrenched channels. [Copyright &y& Elsevier]