Effects of Brush Management on Water Resources

For several decades, land managers have cleared brush species, such as mesquite and juniper (cedar), and observed increases in spring and streamflows. Scientists have also conducted numerous studies in which they have measured the effects of brush removal on different aspects of rangeland hydrology. These include the amount of rainfall that is intercepted and held by the plant leaves, surface runoff, spring flow, water use by individual plants and plant communities, fluctuation of shallow water tables, and streamflows. Considering this very diverse information, many scientists agree on several points: 1. The roots of some brush species extract water from greater depths than do grasses and forbs, and brush control can reduce the total amount of water used by vegetation. 2. Brush and other deep-rooted vegetation growing over shallow aquifers near streams can be expected to use large amounts of groundwater, likely reducing the amount in both the interconnected stream and aquifer. 3. Removal of brush like juniper and live oak from upland areas some distance from streams may increase streamflow and/or recharge aquifers especially when: 1. The brush canopy is dense and intercepts substantial amounts of rainfall (for example: dense juniper [cedar] or live oak stands), effectively reducing the amount of rainfall reaching the soil surface, and 2. Soils, subsoils and/or geologic strata are permeable, and streams in the area are fed by seeps and springs. Water can quickly percolate below the roots of grasses and forbs and move through subsurface pathways to local streams or aquifers. 4. Brush control in upland areas is unlikely to increase significantly water yields if soils and geologic formations are not conducive to increased runoff and/or subsurface flows to streams or to aquifers. 5. For brush control to have substantial long-term impacts on water yield, most or all of the woody vegetation in the treated area should be killed, and regrowth of brush and herbaceous vegetation should be controlled so that it is less dense and more shallow rooted than the pretreatment vegetation. 6. New science-based tools can help pinpoint locations where brush control should substantially increase water flows in streams. 7. A geographically targeted brush control program with careful scientific verification of impacts is needed to guide long-term brush control policies

Wheeler-Dealing: An Essay on Law, Politics, and Speech

Few matters seem to arouse greater feeling than local politics and sport. Each reflects and reinforces common qualities of robust partisanship and vigorous exercise. When the two combine, tempers are guaranteed to run very high. This unpropitious state of affairs occurred in Leicester in the spring of 1984. The city of Leicester has a significant and established black community, about twenty-five per cent of the population are of Asian or Afro-Caribbean origins. Leicester City Council was firmly committed to racial equality. In particular, it supported the Gleneagles Agreement made in 1977 between Commonwealth countries which encouraged taking every practical step to discourage contact with sporting organisations from South Africa . When the English rugby team organised a tour to South Africa and selected three Leicester: players, the council considered the gauntlet to be thrown firmly at its feet. The council allowed the Leicester Rugby Football Club to use a recreation ground for Second XV matches and general training, the First XV played elsewhere

Wheeler-Dealing: An Essay on Law, Politics, and Speech

Few matters seem to arouse greater feeling than local politics and sport. Each reflects and reinforces common qualities of robust partisanship and vigorous exercise. When the two combine, tempers are guaranteed to run very high. This unpropitious state of affairs occurred in Leicester in the spring of 1984. The city of Leicester has a significant and established black community, about twenty-five per cent of the population are of Asian or Afro-Caribbean origins. Leicester City Council was firmly committed to racial equality. In particular, it supported the Gleneagles Agreement made in 1977 between Commonwealth countries which encouraged taking every practical step to discourage contact with sporting organisations from South Africa . When the English rugby team organised a tour to South Africa and selected three Leicester: players, the council considered the gauntlet to be thrown firmly at its feet. The council allowed the Leicester Rugby Football Club to use a recreation ground for Second XV matches and general training, the First XV played elsewhere

Isolation and characterization of microsatellites in the lichen Buellia frigida (Physciaceae), an Antarctic endemic

Premise of the study: Microsatellite markers were characterized for an Antarctic endemic, Buellia frigida, to investigate population structure and origin of Antarctic lichens. Methods and Results: Five primer sets were characterized. All loci were polymorphic with eight to 16 alleles per locus in a sample of 59 lichens. Conclusions: The microsatellite markers potentially provide insight into population structure and gene flow of B. frigida

Reynolds-Averaged Navier-Stokes Simulation of a 2D Circulation Control Wind Tunnel Experiment

Numerical simulations are performed using a Reynolds-averaged Navier-Stokes (RANS) flow solver for a circulation control airfoil. 2D and 3D simulation results are compared to a circulation control wind tunnel test conducted at the NASA Langley Basic Aerodynamics Research Tunnel (BART). The RANS simulations are compared to a low blowing case with a jet momentum coefficient, C(sub u), of 0:047 and a higher blowing case of 0.115. Three dimensional simulations of the model and tunnel walls show wall effects on the lift and airfoil surface pressures. These wall effects include a 4% decrease of the midspan sectional lift for the C(sub u) 0.115 blowing condition. Simulations comparing the performance of the Spalart Allmaras (SA) and Shear Stress Transport (SST) turbulence models are also made, showing the SST model compares best to the experimental data. A Rotational/Curvature Correction (RCC) to the turbulence model is also evaluated demonstrating an improvement in the CFD predictions

Numerical Modelling of Melt Behaviour in the Lower Vessel Head of a Nuclear Reactor

Acknowledgements The authors would like to thank the EPSRC MEMPHIS multi-phase programme grant, the EPSRC Computational modelling for advanced nuclear power plants project and the EU FP7 projects THINS and GoFastR for helping to fund this work.Peer reviewedPublisher PD

Effects of Brush Management on Water Resources

For several decades, land managers have cleared brush species, such as mesquite and juniper (cedar), and observed increases in spring and streamflows. Scientists have also conducted numerous studies in which they have measured the effects of brush removal on different aspects of rangeland hydrology. These include the amount of rainfall that is intercepted and held by the plant leaves, surface runoff, spring flow, water use by individual plants and plant communities, fluctuation of shallow water tables, and streamflows. Considering this very diverse information, many scientists agree on several points: 1. The roots of some brush species extract water from greater depths than do grasses and forbs, and brush control can reduce the total amount of water used by vegetation. 2. Brush and other deep-rooted vegetation growing over shallow aquifers near streams can be expected to use large amounts of groundwater, likely reducing the amount in both the interconnected stream and aquifer. 3. Removal of brush like juniper and live oak from upland areas some distance from streams may increase streamflow and/or recharge aquifers especially when: 1. The brush canopy is dense and intercepts substantial amounts of rainfall (for example: dense juniper [cedar] or live oak stands), effectively reducing the amount of rainfall reaching the soil surface, and 2. Soils, subsoils and/or geologic strata are permeable, and streams in the area are fed by seeps and springs. Water can quickly percolate below the roots of grasses and forbs and move through subsurface pathways to local streams or aquifers. 4. Brush control in upland areas is unlikely to increase significantly water yields if soils and geologic formations are not conducive to increased runoff and/or subsurface flows to streams or to aquifers. 5. For brush control to have substantial long-term impacts on water yield, most or all of the woody vegetation in the treated area should be killed, and regrowth of brush and herbaceous vegetation should be controlled so that it is less dense and more shallow rooted than the pretreatment vegetation. 6. New science-based tools can help pinpoint locations where brush control should substantially increase water flows in streams. 7. A geographically targeted brush control program with careful scientific verification of impacts is needed to guide long-term brush control policies

2-D Circulation Control Airfoil Benchmark Experiments Intended for CFD Code Validation

A current NASA Research Announcement (NRA) project being conducted by Georgia Tech Research Institute (GTRI) personnel and NASA collaborators includes the development of Circulation Control (CC) blown airfoils to improve subsonic aircraft high-lift and cruise performance. The emphasis of this program is the development of CC active flow control concepts for both high-lift augmentation, drag control, and cruise efficiency. A collaboration in this project includes work by NASA research engineers, whereas CFD validation and flow physics experimental research are part of NASA s systematic approach to developing design and optimization tools for CC applications to fixed-wing aircraft. The design space for CESTOL type aircraft is focusing on geometries that depend on advanced flow control technologies that include Circulation Control aerodynamics. The ability to consistently predict advanced aircraft performance requires improvements in design tools to include these advanced concepts. Validation of these tools will be based on experimental methods applied to complex flows that go beyond conventional aircraft modeling techniques. This paper focuses on recent/ongoing benchmark high-lift experiments and CFD efforts intended to provide 2-D CFD validation data sets related to NASA s Cruise Efficient Short Take Off and Landing (CESTOL) study. Both the experimental data and related CFD predictions are discussed

Numerical Modelling of Debris Bed Water Quenching

Acknowledgements The authors would like to thank the EPSRC MEMPHIS multi-phase programme grant, the EPSRC Computational modelling for advanced nuclear power plants project, the EU FP7 projects THINS and GoFastR and ExxonMobil for helping to fund this work.Peer reviewedPublisher PD

Overview of CFD Validation Experiments for Circulation Control Applications at NASA

Circulation control is a viable active flow control approach that can be used to meet the NASA Subsonic Fixed Wing project s Cruise Efficient Short Take Off and Landing goals. Currently, circulation control systems are primarily designed using empirical methods. However, large uncertainty in our ability to predict circulation control performance has led to the development of advanced CFD methods. This paper provides an overview of a systematic approach to developing CFD tools for basic and advanced circulation control applications. This four-step approach includes "Unit", "Benchmar", "Subsystem", and "Complete System" experiments. The paper emphasizes the ongoing and planned 2-D and 3-D physics orientated experiments with corresponding CFD efforts. Sample data are used to highlight the challenges involved in conducting circulation control computations and experiments