A method is presented of estimating the electrical conductivity (EC) of a saturated paste extract (ECe) from the EC of a 1 to 5 soil-water suspension (EC1: 5) and an estimate of soil texture. The ...method has application in soil testing laboratories which routinely determine EC1:5 but not ECe. The method of preparing the saturated paste by capillary wetting is also compared with the standard method of hand mixing. The coefficient (f) relating ECe to EC1:5, was found to be related to the water content of the saturated paste (WSP). The relationship between WSP and texture, determined by hand working, indicates that the uncertainty associated with use of this relationship could be significant in sandy soils. Wetting the soil by capillary rather than by hand mixing resulted in a lower saturation percentage and higher ECe but dissolved the same amount of salts. The capillary wetting method is preferred as it greatly reduces labour time.
We present the Fortran code
SusyBSG version
1.1, which computes the branching ratio for the decay
B
→
X
s
γ
in the MSSM with Minimal Flavor Violation. The computation takes into account all the ...available NLO contributions, including the complete supersymmetric QCD corrections to the Wilson coefficients of the magnetic and chromomagnetic operators.
Program title: SusyBSG
Catalogue identifier: AEBM_v1_0
Program summary URL:
http://cpc.cs.qub.ac.uk/summaries/AEBM_v1_0.html
Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland
Licensing provisions: Standard CPC licence,
http://cpc.cs.qub.ac.uk/licence/licence.html
No. of lines in distributed program, including test data, etc.: 99 155
No. of bytes in distributed program, including test data, etc.: 708 850
Distribution format: tar.gz
Programming language: Fortran
Computer: All computers with a Fortran compiler
Operating system: Linux
Classification: 11.6
Nature of problem: Predicting the branching ratio for the decay
B
→
X
S
γ
in the MSSM with Minimal Flavor Violation.
Solution method: We take into account all the available NLO contributions, including the two-loop gluino contributions to the Wilson coefficients computed in Ref. 1. The relation between the Wilson coefficients and the branching ratio for
B
→
X
S
γ
is computed along the lines of Ref. 2. The SUSY input parameters can be read from a spectrum file in the SLHA format.
Restrictions: The results apply only to the case of Minimal Flavor Violation.
Unusual features: Numerical instabilities may arise for special combinations of the input parameters. They can usually be avoided by compiling the code in quadruple precision.
Running time: Approximately 10 ms in double precision, 0.5 s in quadruple precision (on a Pentium D 3.40-GHz).
References:
1
G. Degrassi, P. Gambino and P. Slavich, Phys. Lett. B 635 (2006) 335,
arXiv:hep-ph/0601135.
2
P. Gambino and M. Misiak, Nucl. Phys. B 611 (2001) 338,
hep-ph/0104034.
Shallow saline water tables underline large areas of the Riverine Plains of the Murray Basin of southern Australia. It is believed that deep-rooted perennial plants in these areas are able to reduce ...recharge and use shallow groundwater, thus controlling groundwater levels. Lysimeters represent the best experimental technique for investigating capillary upflow from shallow water tables and the associated processes of salt accumulation, plant water use, and growth response. Techniques involving stable isotopes of water help determine the components of upflow due to vegetation. When combined with models that stimulate salt and water movement in the soil zone and the plant water use and growth, we can thoroughly test our understanding of salinity processes and the ability of plants to control water tables. Results from WAVES simulations of plant growth, evapotranspiration, groundwater uptake, salt accumulation, and the impacts on lucerne growth are compared against measurements made in lysimeters at Griffith, NSW, Australia. With minimal calibration, WAVES was able to reproduce both the daily and seasonal variation in evapotranspiration, upward flux from the groundwater table, plant growth in terms of leaf area development, soil water profiles, soil water salinity, and root water extraction patterns. There was a decline of 36% in transpiration, 42% in leaf area growth, and 67% in upward flux after the salinity of the water table increased from 0.1 to 16
dS
m
−1. Although the upward flux of water was large, lucerne used little of it (< 20%), preferring `fresher' rainfall and irrigation water near the surface. Given the tests presented in this work, we think WAVES is applicable to irrigated agricultural systems.
We compute the
O(α
tα
s)
two-loop corrections to the neutral Higgs boson masses in the Minimal Supersymmetric extension of the Standard Model. An appropriate use of the effective potential allows us ...to obtain simple analytical formulae, valid for arbitrary values of
m
A
and of the mass parameters in the stop sector. We elucidate some subtleties of the effective potential calculation, and find full agreement with the numerical output of the existing diagrammatic calculation. We discuss in detail the limit of heavy gluino.
We study the
O(α
tα
s+α
t
2)
two-loop corrections to the minimization conditions of the MSSM effective potential, providing compact analytical formulae for the Higgs tadpoles. We connect these ...results with the renormalization group running of the MSSM parameters from the grand unification scale down to the weak scale, and discuss the corrections to the Higgs mixing parameter
μ and to the running CP-odd Higgs mass
m
A
in various scenarios of gravity-mediated SUSY breaking. We find that the
O(α
tα
s)
and
O(α
t
2)
contributions partially cancel each other in the minimization conditions. In comparison with the full one-loop corrections, the
O(α
tα
s+α
t
2)
two-loop corrections significantly weaken the dependence of the parameters
μ and
m
A
on the renormalization scale at which the effective potential is minimized. The residual two-loop and higher-order corrections to
μ and
m
A
are estimated to be at most 1% in the considered scenarios.
Reduced flooding and raised watertables have caused increased soil salinity and die-back of native forests on the floodplains of the lower River Murray of south Australia. Proposed management options ...include increasing flood frequency by regulating flows from upstream storages, and groundwater pumping to lower the watertable. This paper uses a soil-vegetation-atmosphere-transfer model (WAVES) to evaluate the impact of these proposals on soil salinisation processes and vegetation growth (black box,
Eucalyptus largiflorens) for soils with different hydraulic properties. The changes in canopy leaf mass and plant available soil water were simulated for the period 1970–1994 using historical daily climate and river level records. The river level records were used to reconstruct the flooding and watertable history of sites where tree water use studies were conducted to calibrate the model. Then the watertable depth and/or flooding frequency was modified and the changes in the canopy leaf mass and soil water availability relative to the historical simulation were evaluated. The simulations suggest that, with the present watertable and flooding regime, very large floods (e.g. 205 days as in 1974–1976) are needed to sustain tree cover on the higher parts of the floodplain where die-back is most severe. They also indicate that soil hydraulic properties have a large influence on the magnitude and time scale of the growth response of salt stressed vegetation to floods and salt accumulation. Infrequently flooded vegetation exhibiting die-back was predicted to increase its canopy leaf area for up to 12 years following the large floods of 1974 and 1976, at sites where the soil was relatively permeable and groundwater highly saline (EC
=
55
dS
m
−1). The changes in canopy leaf area in response to the floods was predicted to be relatively small on sites with heavier clay soils. The growth response of the vegetation to a long term lowering of watertable depth by 1
m was greater than that induced by the small potential increase in flooding frequency which is feasible given the current water storage limitations. The simulations predict that changes in the average annual soil water availability which arise from flood events and soil salinisation, drive a long term cycle in the annual average transpiration rate per unit leaf area suggesting the soil-plant-climate system is adjusting towards a hydrological equilibrium but is not in equilibrium. The proposed management options may control die-back in parts of the floodplain with more slowly salinising heavy clay soils and lower salinity groundwater but are unlikely to prevent die-back on relatively permeable soils with high salinity groundwater. However, they may assist vegetation survival between the long duration flood events which appear to be essential to sustain tree cover on the higher floodplain. The management options need to be evaluated further at the floodplain scale using the understanding from site specific conditions to test simple approaches which can be linked to a geographic information system (GIS) of the floodplain.
Old man saltbush (
Atriplex nummularia) has been widely planted on salt affected land in south-east Australia to provide a vegetative cover which can be used as a fodder reserve. Such plantations are ...also perceived as having the capacity to use saline groundwater and hence affect the extent of shallow watertables. This paper examines the water use characteristics of saltbush plantations which are regularly grazed and established above shallow watertables (1–2
m). Soil chloride, water content, soil water and sap isotope composition (
δ
2H), leaf water potential, stomatal conductance, sap flow and climatic conditions were monitored during dry summer and moist winter conditions at two plantations in southern NSW. The results indicated that the transpiration rate of old man saltbush was very low (less than 0.3
mm day
−1) throughout the monitoring period. The low transpiration rates were associated with a low leaf area index (0.35), low stomatal conductances and low xylem water potentials. At most times of the year the plants used shallow water sources derived mainly from rainfall. However, up to half the transpiration at the driest time of year (March) was derived from groundwater. Although saltbush can establish and grow slowly on highly saline land its capacity to transpire saline groundwater is small relative to rechange from irrigation and rainfall. Hence, saltbush plantations are likely to have a negligible hydrological impact.
Farm woodlots or plantations of salt tolerant trees may provide an economic use or reclamation treatment for salt-affected farmland within the irrigation regions of the Indus Valley, but the ...hydrological impact and sustainability of such plantations are unknown. Detailed measurements of plantation water use, watertable depth and soil conditions were recorded over 2 years in two small plantations with contrasting soil and groundwater salinity at Tando Jam in the Sindh province of Pakistan. The species monitored were
Acacia nilotica, A. ampliceps and
Prosopis pallida. Annual water use by 3- to 5-year old
A. nilotica was 1248 mm on the severely saline site and 2225 mm on the mildly saline site. Water use by the other species was less than 25% of these rates, but this difference is largely explained by their lower density in terms of sapwood area per hectare. Water use by
A. nilotica was considerably greater than annual rainfall, implying uptake of groundwater which was confirmed both by piezometric observations and chloride balance modelling to predict vertical water movement through the root zone. Plantation watertables fell from 1.7 m below surface in March to over 2.9 m in September, then rose again during irrigation of the surrounding farmland. Root zone salt concentrations remained high at the more saline site throughout the monitoring period, but at the less saline site there was evidence of increasing root zone salinity as salt accumulated in areas of the profile subject to root water uptake. Salt concentration in the upper profile decreased as the soil dried and water was absorbed from greater depth. Plantations using saline groundwater may be sustainable if occasional leaching and other salt-removing processes are sufficient to maintain root zone salinity at a level which does not excessively reduce tree growth.
We compute the
O(α
t
2)
two-loop corrections to the neutral CP-even Higgs boson mass matrix in the Minimal Supersymmetric Standard Model, for arbitrary values of
m
A
and of the parameters in the stop ...sector, in the effective potential approach. In a large region of parameter space these corrections are sizeable, increasing the prediction for
m
h
by several GeV. We present explicit analytical formulae for a simplified case. We discuss the inclusion of momentum-dependent corrections and some possible ways of assigning the input parameters.
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