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A new governing equation of watertable dynamics was derived.A new analytical solution for watertable fluctuations was derived.The effect of finite unsaturated zone thickness was examined. Parlange and Brutsaert (1987) derived a modified Boussinesq equation to account for the capillary effect on water table dynamics in unconfined aquifers. Barry et al. (1996) solved this equation subject to a periodic boundary condition. Their solution shows significant influence of capillarity on water table fluctuations, which evolve to finite‐amplitude standing waves at the high frequency limit. Here we propose a new governing equation for the water table, which considers both horizontal and vertical flows in an unsaturated zone of finite thickness. An approximate analytical solution for periodic water table fluctuations based on the new equation was derived. In agreement with previous results, the analytical solution shows that the unsaturated zone's storage capacity permits water table fluctuations to propagate more readily than predicted by the Boussinesq equation. Furthermore, the new solution reveals a capping effect of the unsaturated zone on both the amplitude and phase of the water table fluctuations as well as the water table overheight. Due to the finite thickness of the unsaturated zone, the capillary effect on water table fluctuations is modified mainly with reduced amplitude damping and phase shift.

After an initial evaluation of several solvents, the efficiency of Soxhlet extractions with isopropanol/ammonia (s.g. 0.88) (70 : 30 v : v; 24 h) in extracting compounds associated with water repellency in sandy soils was examined using a range of repellent and wettable control soils (n = 15 and 4) from Australia, Greece, Portugal, The Netherlands, and the UK. Extraction efficiency and the role of the extracts in causing soil water repellency was examined by determining extract mass, sample organic carbon content and water repellency (after drying at 20C and 105C) pre- and post-extraction, and amounts of aliphatic C?H removed using DRIFT, and by assessing the ability of extracts to cause repellency in acid-washed sand (AWS).  Key findings are: (i) none of organic carbon content, amount of aliphatic C?H, or amount of material extracted give any significant correlation with repellency for this diverse range of soils; (ii) sample drying at 105C is not necessarily useful before extraction, but may provide additional information on extraction effectiveness when used after extraction; (iii) the extraction removed repellency completely from 13 of the 15 repellent samples; (iv) extracts from all repellent and wettable control soils were capable of inducing repellency in AWS. The findings suggest that compounds responsible for repellency represent only a fraction of the extract composition and that their presence does not necessarily always cause repellency.

A modified version of the popular agrohydrological model SWAP has been used to evaluate modelling of soil water flow and crop growth at field situations in which water repellency causes preferential flow. The parameter sensitivity in such situations has been studied. Three options to model soil water flow within SWAP are described and compared: uniform flow, the classical mobile-immobile concept, and a recent concept accounting for the dynamics of finger development resulting from unstable infiltration. Data collected from a severely water-repellent affected soil located in Australia were used to compare and evaluate the usefulness of the modelling options for the agricultural management of such soils.  The study shows that an assumption of uniform flow in a water-repellent soil profile leads to an underestimation of groundwater recharge and an overestimation of plant transpiration and crop production. The new concept of modelling taking finger dynamics into account provides greater flexibility and can more accurately model the observed effects of preferential flow compared with the classical mobile?immobile concept. The parameter analysis indicates that the most important factor defining the presence and extremity of preferential flow is the critical soil water content.  Comparison of the modelling results with the Australian field data showed that without the use of a preferential flow module, the effects of the clay amendments to the soil were insufficiently reproduced in the dry matter production results. This means that the physical characteristics of the soil alone are not sufficient to explain the measured increase in production on clay amended soils. However, modelling with the module accounting for finger dynamics indicated that the preferential flow in water repellent soils that had not been treated with clay caused water stress for the crops, which would explain the decrease in production.

Copper is an important micronutrient and trace amounts are essential for crop growth. However, high concentrations of copper will produce toxic effects. Australia is increasingly developing production of crops in water repellent soils. Clay amendment, a common amelioration techniques used in Australia, has demonstrated agronomic benefits in increased crop or pasture production. The sorption and desorption of copper and the effect of clay treatment on copper behaviour in a water repellent soil collected from an experimental farm in South Australia is studied. We found that the water repellent soils amended with clay have an increased adsorption capacity of copper. Also the clay-amended soils had an increased ratio of specific sorption to total sorption of copper. The implications of this study to the sustainable agro-environmental management of water repellent soils is discussed.

Australia is a water-stressed nation and demand on potable water supply is increasing. Consequently water conservation and reuse are increasingly becoming important. Irrigation of recycled wastewater on water repellent soils is a technology that is being trialled as a means of improving crop production and conserving potable supply. However, recycled water contains potentially harmful heavy metals. This paper reports the competitive sorption and desorption of several common heavy metals found in soils collected from a farm located in the south-east of South Australia. The soil from this location is severely water repellent, but some sites were amended with kaolinite clay (Si4Al4O10(OH)8) about 7 and 15 years ago. The metals studied were Cu, Pb, Cd, Cr, Ni, and Zn. Competitive sorption of the metals was distinctly observed. For all heavy metals, the quantity of metal sorbed was higher in amended soil, and there was a strong correlation between the specific sorption to total sorption ratio and the amount of clay in the soil. The sorption intensities varied with metal, Cr, Pb, and Cu having a high sorption tendencies and Zn, Cd, and Ni having comparatively low sorption tendencies. The total sorption capacity for all metals increased in clay-treated soils compared with non-treated soils. On average, clay-amended water repellent soils had a 20?40% increased capacity to adsorb total metals; however, this increase was largely caused by the increased capacities to adsorb Zn, Cd, and Ni. The effect of clay treatment largely enhanced the sorption capacity of relatively weakly adsorbing heavy metals. The implications for using recycled wastewater on the long-term sustainable agro-environmental management of these soils are discussed.

The concentrations of 24 elements in the sediment and associated water column were monitored at two sites, one an area of intensive cage culture of carp, the other a wild site far from known cage culture areas, in Lake Kasumigaura, Japan, between September 1994 and September 1995. The concentrations of most elements in Lake Kasumigaura are mostly sub-parts per billion, except those for Ca, Fe, K, Mg, Na, P, and Si. The concentrations of Cd, Co, Cu, Mn, Ni, Pb, V, and Fe in Lake Kasumigaura are higher than the values in Lake Mashu, Lake Shikotsu, and Lake Biwa, and comparable to the levels in open ocean. Statistically significant differences in metal concentrations were observed between the culture and wild sites, with metal concentrations consistently higher at the culture site. Although cage culture of carp in the Lake Kasumigaura system may be causing localized increase in metal concentrations in the sediments, we must treat the results with caution, since the concentrations of metals observed in the sediments in 1995 were lower than those observed in 1979 for all metals at both sampling sites. In conclusion, further study of the concentrations of metals in the lake as a whole must be undertaken before the differences between the culture and wild sites can be proved, or disproved, to be the result of carp culture.

Temporal moments analysis of solute breakthrough curves is used to investigate the preferential leaching of chloride, nitrate and phosphate through an Australian soil. Recent studies have shown that current models and methods do not adequately describe the leaching of nutrients through soil, often underestimating the risk of groundwater contamination by surface-applied chemicals, and overestimating the concentration of resident solutes. This inaccuracy results primarily from ignoring soil structure and non-equilibrium between soil constituents, water and solutes. Therefore simple models are required to accurately characterise solute transport in natural and agricultural soils under non-equilibrium conditions. A multiple sample percolation system, consisting of 25 individual collection wells was constructed to study the effects of localised soil heterogeneities on the transport of nutrients (NO3−, Cl−, PO43−) in the vadose zone of an agricultural soil predominantly dominated by clay. Using data collected from the multiple sample percolation experiments, this paper compares and contrasts the performance of temporal moments analysis with two mathematical models for predicting solute transport, the advective-dispersion model with a reaction term (ADR) and a two-region preferential flow model (TRM) suitable for modelling preferential transport. The values for solute transport parameters predicted by temporal moments analysis were in excellent agreement with experimental data and results from ADR and TRM. It is concluded that temporal moments analysis when applied with other physical models such as the ADR and TRM, provide an excellent means of obtaining values for important solute transport parameters and gaining insight of preferential flow. These results have significant ramifications for modelling solute transport and predicting nutrient loadings.

Small volumes of a commercial timber preservative containing approximately 60% w/w chromated copper arsenic (CCA) were applied to 15-cm-deep, undisturbed soil monolith lysimeters containing the surface horizon of a mildly acidic, sandy loam soil extracted from within the forestry plantation region of south-west Victoria. The collected leachate and samples of the core profiles were analysed by inductively coupled plasma emission spectroscopy (ICP-ES) for a total of 28 elements, including the active ingredients of the preservative, copper, chromium, and arsenic.After application of CCA, of the metals studied, only the concentrations of arsenic, calcium, chromium, sodium, and potassium in the leachate differed from background concentrations during the irrigation of the cores. Copper concentrations in all leachate remained at background levels throughout the experiment. Up to 36% of the applied dose of chromium was detected in the leachate, with breakthrough at 15 cm soil depth occurring within 20 days of preservative application. Up to 13% of the applied dose of arsenic was detected in the leachate collected at 15 cm depth, although in this case breakthrough was not observed until 25 days after preservative application. The applied copper was immobilised in the top 4 cm of the soil. Elevated concentrations of arsenic and chromium were found in the top 6 cm of the soil profile.

Cross-shore interactions between the ocean and a coastal aquifer have been studied extensively, whereas the corresponding along-shore case has seldom been examined. This paper presents a numerical model that simulates two-dimensional groundwater flow averaged over the thickness of a coastal aquifer. The model is used to examine the essential features of tide-induced, along-shore effects on an aquifer adjacent to a cross-shore river. The results show that the tide, which fluctuates the water level in the river, induces groundwater table fluctuations and oscillating flows in the along-shore direction. This occurs even at locations much further inland than tidal cross-shore fluctuations can propagate. However, the magnitude of along-shore water table fluctuations and flow velocity at a given cross-shore distance decreases with the distance from the river in the same manner as cross-shore tidal fluctuations. The along-shore groundwater flow, together with the cross-shore flow, forms horizontal circulation and increases mixing of solute in the aquifer. Over a tidal period, a large amount of water exchange occurs at the river-aquifer and ocean-aquifer interfaces, leading to increased transfer of chemicals between the three water bodies. These results have implications for the management of waste discharge in estuaries and coastal aquifers.

A multisegment percolation system (MSPS) consisting of 25 individual collection wells was constructed to study the effects of localised soil heterogeneities on the transport of solutes in the vadose zone. In particular, this paper discusses the transport of water and nutrients (NO3_, Cl-, PO43-) through structurally stable, free-draining agricultural soil from Victoria, Australia. A solution of nutrients was irrigated onto the surface of a large undisturbed soil core over a 12-h period. This was followed by a continuous irrigation of distilled water at a rate which did not cause ponding for a further 18 days. During this time, the volume of leachate and the concentration of nutrients in the leachate of each well were measured. Very significant variation in drainage patterns across a small spatial scale was observed. Leaching of nitrate-nitrogen and chloride from the core occurred two days after initial application. However, less than 1% of the total applied phosphate-phosphorus leached from the soil during the 18-day experiment, indicating strong adsorption. Our experiments indicate considerable heterogeneity in water flow patterns and solute leaching on a small spatial scale. These results have significant ramifications for modelling solute transport and predicting nutrient loadings on a larger scale.

Multiple sampling is widely used in vadose zone percolation experiments to investigate the extent in which soil structure heterogeneities influence the spatial and temporal distributions of water and solutes. In this note, a simple, robust, mathematical model, based on the β-statistical distribution, is proposed as a method of quantifying the magnitude of heterogeneity in such experiments. The model relies on fitting two parameters, αand ζto the cumulative elution curves generated in multiple-sample percolation experiments. The model does not require knowledge of the soil structure. A homogeneous or uniform distribution of a solute and/or soil–water is indicated by α= ζ= 1. Using these parameters, a heterogeneity index (HI) is defined as 3times the ratio of the standard deviation and mean. Uniform or homogeneous flow of water or solutes is indicated by HI = 1 and heterogeneity is indicated by HI >1. A large value for this index may indicate preferential flow. The heterogeneity index relies only on knowledge of the elution curves generated from multiple sample percolation experiments and is, therefore, easily calculated. The index may also be used to describe and compare the differences in solute and soil–water percolation from different experiments. The use of this index is discussed for several different leaching experiments.

This paper investigates leaching of water and nutrients (NO‐3, Cl‐, PO3‐4) from the unsaturated layer in an Australian soil using a multisegment percolation system (MPS). Large undisturbed soil cores were collected from a clay‐based, basaltic plain, agricultural soil at Grassmere, 300 km west of Melbourne, Australia. Significant heterogeneity (or preferential flow) of effluent moisture and solutes was detected (one‐way ANO VA, p< 0.001). Fifty percent of the applied nitrate and chloride leached from the soil core within three days after initial application. Hundred percent of the applied nitrate and chloride leached from the soil core within 8 days after application. These results indicate little incorporation into the soil matrix, and possible denitrification or mineralisation. In contrast, after 18 days, less than 1 % of the total applied phosphates leached from the soil, indicating strong adsorption. Our experiments indicate considerable heterogeneity in water flow patterns and solute leaching on a small spatial scale. Very rapid transport of nitrate and chloride through the soil was evident, in comparison phosphate leaching was negligible. These results have important implications for the management of nutrient schedules in agricultural soils, particularly those located in the Western District of Victoria, Australia.

We observed and analyzed the flow of water in a shallow hillslope layer over a fragipan during and after an artificial precipitation event. Although most of the fragipan was made up of material essentially impermeable, the cracks within the fragipan carried significant portions of the interflow. Consequently, the average distance between the cracks within the fragipan is the main controlling factor in determining the subsurface flow in the shallow surface layer.

Somatostatin (SST) is used in the treatment of acute pancreatitis (AP) to inhibit pancreatic exocrine secretion, which represents one of the goals of medical treatment in this disease. Its therapeutic efficacy, however, is poor. One hypothesis, which has not yet been investigated, is that i.v. SST might be broken down by blood proteolytic enzymes. In order to evaluate the structural integrity and biological activity of infused SST, somatostatin-like immunoreactivity (SLI) and levels of pancreatic enzymes were monitored in the blood stream during the infusion of SST-14 (3,5 μg/kg/h for 48 h) in eight patients with severe acute pancreatitis. SLI was measured by both radioimmunoassay (RIA) and high-pressure liquid chromatography (HPLC). The results indicate that SLI levels increase promptly after the beginning of infusion, with a slower increase between 6 and 36 h, and a rapid increase again at 48 h. HPLC analysis shows a single peak of SLT with the same retention time as standard SST-14. Total amylase, lipase, and trypsinogen significantly decreased compared with pretreatment values (48, 63.1, and 77.4, respectively) after 24 h of SST infusion, while a decrease in elastase 1 (62.6) was observed later at 48 h. These results indicate that in severe AP, somatostatin recovered in plasma retains its biological activity: it inhibits pancreatic circulating enzymes, an action not influenced by breakdown of the peptide, as demonstrated by HPLC of the SLI measured in plasma.

An equation of state was used to prepare a standard table for the solubility of oxygen in sodium chloride sobutions at temperatures between 0 and 35°C and for concentrations up to saturation (260 ppt). The uncertainty introduced by linear interpolation between DO values in the table is less than the experimental uncertainty of data which was used to generate the equation of state. Where pressures differ from 1 atm the DO value from the table can be corrected provided the equilibrium vapour pressure of the salt solution is known. Where this is not the case an approximate correction (±0.5 per cent) can be used provided atmospheric pressure is in the range 950 to 1030 mbar.

Breast carcinoma has a metastatic potential to any organ system. However, breast carcinoma metastases to the urinary tract have very rarely been described. The authors present the case of a patient with a synchronous right ureteral and vesical metastasis of a breast cancer. This is the unique case reported in Literature of synchronous urinary metastatic localization from breast invasive lobular carcinoma.