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This study reports the preliminary results from a statistical screening of tree-ring width records from the International Tree-Ring Data Bank (ITRDB), to evaluate the strength of the hydrological signal, in dendrochronological records from the Tennessee Valley. We used United States Geological Survey (USGS) streamflow data from 11 gages, within the Tennessee Valley, and regional tree-ring chronologies, to analyze the dendroclimatic potential of the region, and create seasonal flow reconstructions. Prescreening methods included correlation, date, and temporal stability analysis of predictors to ensure practical and reliable reconstructions. Seasonal correlation analysis revealed that large numbers of regional tree-ring chronologies were significantly correlated (p ≤ 0.05) with the May–June–July streamflow. Stepwise linear regression was used to create the May–June–July streamflow reconstructions. Ten of the 12 streamflow stations were considered statistically skillful (R2 ≥ 0.40). Skillful reconstructions ranged from 208 to 301 years in length, and were statistically validated using leave-one-out cross validation, the sign test, and a comparison of the distribution of low flow years. The long-term streamflow variability was analyzed for the Nolichucky, Nantahala, Emory, and South Fork (SF) Holston stations. The reconstructions revealed that while most of the Western United States (U.S.). was experiencing some of its highest flow years during the early 1900s, the Tennessee Valley region was experiencing a very low flow. Results revealed the potential benefit of using tree-ring chronologies to reconstruct hydrological variables in the Southeastern U.S., by demonstrating the ability of proxy-based reconstructions to provide useful data beyond the instrumental record.

The identification of Atlantic Ocean (AO) climatic drivers may prove valuable in long lead-time forecasting of streamflow in the Adour-Garonne basin in southwestern France. Previous studies have identified the Atlantic Multidecadal Oscillation (AMO) and the North Atlantic Oscillation (NAO) as drivers of European hydrology. The current research applied the singular value decomposition (SVD) statistical method to AO sea-surface temperatures (SSTs) to identify the primary AO climatic drivers of the Adour-Garonne basin streamflow. Annual and seasonal streamflow volumes were selected as the hydrological response, while average AO SSTs were calculated for three different 6-month averages (January-June, April-September and July-December) for the year preceding streamflow. The results identified a region along the Equator as the probable driver of the basin streamflow. Additional analysis evaluated the influence of the AMO and NAO on Adour-Garonne basin streamflow.

Soil moisture is an important factor in the global hydrologic cycle, but existing reconstructions of historic soil moisture are limited. We used tree-ring chronologies to reconstruct annual soil moisture in the Upper Colorado River Basin (UCRB). Gridded soil moisture data were spatially regionalized using principal components analysis and k-nearest neighbor techniques. We correlated moisture sensitive tree-ring chronologies in and adjacent to the UCRB with regional soil moisture and tested the relationships for temporal stability. Chronologies that were positively correlated and stable for the calibration period were retained. We used stepwise linear regression to identify the best predictor combinations for each soil moisture region. The regressions explained 42-78% of the variability in soil moisture data. We performed reconstructions for individual soil moisture grid cells to enhance understanding of the disparity in reconstructive skill across the regions. Reconstructions that used chronologies based on ponderosa pines (Pinus ponderosa) and pinyon pines (Pinus edulis) explained more variance in the datasets. Reconstructed soil moisture data was standardized and compared with standardized reconstructed streamflow and snow water equivalent data from the same region. Soil moisture and other hydrologic variables were highly correlated, indicating reconstructions of soil moisture in the UCRB using tree-ring chronologies successfully represent hydrologic trends.(KEY TERMS: soil moisture; reconstruction; tree-ring chronologies; Upper Colorado River Basin; drought.) Anderson, SallyRose, Glenn Tootle, and Henri Grissino-Mayer, 2012. Reconstructions of Soil Moisture for the Upper Colorado River Basin Using Tree-Ring Chronologies.

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WoUNDs to the dorsal aspect of the skull of horses that involve fracture of the frontal bones into the conchofrontal sinus are not uncommon. Healing of these wounds can be complicated by bacterial sinusitis, formation of a sinocutaneous fistula and/or facial deformity. The closure of wounds penetrating the conchofrontal sinus is often delayed, either due to neglect or because of concerns about infection that could accompany primary closure. Delayed closure of sino cutaneous fistulae with muscle and/or periosteal flaps has been described by campbell and Peyton (1984), schumacher and others (1985), Dart and others (1994) and charman and Vasey (2007). This short communication describes the successful primary closure of a large facial wound in a horse, complicated by a comminuted fracture of the frontal bone into the conchofrontal sinus, using pedicles of the temporal muscles and underlying periosteum. a three-year-old thoroughbred gelding was referred to the University of Tennessee large animal Hospital within 24 hours of sustaining a facial wound complicated by fracture of the frontal bone with exposure of the conchofrontal sinus. The cause of the injury was unknown. The horse had been seen by a referring veterinarian, who cleaned the wound, administered 2 g phenylbutazone intravenously and referred the horse for definitive treatment. on presentation, physical examination revealed no abnormalities except for a large, T-shaped, jagged wound, 8 cm wide x 18 cm long, that penetrated into the right conchofrontal sinus from the caudal aspect of the frontal sinus on the midline to the level of the medial canthus of the right eye, 4 cm to the right of the midline (Fig 1). several detached fragments of frontal bone were visible within the conchofrontal sinus. an endoscopic evaluation of the nasal cavities revealed no abnormalities. apart from blood clots and bone fragments from the fracture, no abnormalities were observed during endoscopic examination through the wound into the conchofrontal sinus. corrective surgery was performed with the horse standing in stocks and sedated. The horse was medicated with 6.6 mg/kg gentamicin sulphate (Gentafuse; Butler) and 22,000 iu potassium penicillin (Pfizerpen; Pfizer) and initially sedated with 0.01 mg/kg detomidine (Domosedan; Pfizer) and 0.02 mg/kg butorphanol (Torbugesic; Fort Dodge), all administered intravenously. sedation was maintained throughout the procedure with detomidine and xylazine, administered intravenously to effect. The wound was cleaned with 4 per cent chlorhexidine and high-pressure lavage with physiological sterile saline.