ALBERT

Description / Table of Contents: 1. Introduction to Hydrologic Science: Definition and Scope of Hydrology / Development of Scientific Hydrology. - 2. Basic Hydrologic Concepts: Physical Quantities and Laws / Hydrologic Systems / The Conservation Equations / The Watershed (Drainage Basin) / The Regional Water Balance / Spatial Variability / Temporal Variability / Storage, Storage Effects, and Residence Time / Hydrologic Modeling. - 3. Climate, the Hydrologic Cycle, Soils, and Vegetation: A Global Overview: Basic Aspects of Global Climate / The Global Hydrologic Cycle / Climate, Soils, and Vegetation. - 4. Precipitation: Meteorology of Precipitation / Measurement at a Point / Areal Estimation / Precipitation and Rainfall Climatology / Precipitation Quality. - 5. Snow and Snowmelt: Material Characteristics of Snow / Measurement of Snow and Snowmelt / Hydrologic Importance and Distribution of Snow / Snowmelt Processes / Snowmelt Modeling / Water-Quality Aspects. - 6. Water in Soils: Infiltration and Redistribution: Material Properties of Soil / Soil-Water Storage / Soil-Water Flow / Water Conditions in Natural Soils / Infiltration: Measurement and Qualitative Description / Quantitative Modeling of Infiltration at a Point / Redistribution. - 7. Evapotranspiration: Physics of Evaporation and Turbulent Energy Exchange / Classification of Evapotranspiration Processes / Free-Water, Lake, and Wetland Evaporation / Bare-Soil Evaporation / Transpiration / Interception and Interception Loss / Potential Evapotranspiration / Actual Evapotranspiration. - 8. Ground Water in the Hydrologic Cycle: Basic Principles of Ground-Water Flow / Regional Ground-Water Flow / Ground-WaterSurface-Water Reltions / Ground Water in the Regional Water Balance / Evaluation of Ground-Water-Balance Components / Impacts of Ground-Water Development on Basin Hydrology. - 9. Stream Response to Water-Input Events: Basic Aspects of Stream Response / Mechanisms Producing Event Response / Open-Channel Flow and Streamflow Routing / The Stream Network / Rainfall-Runoff Modeling / Rainfall-Runoff Models. - 10. Hydrology and Water-Resource Management: Water-Resource Management / Hydrologic Analysis: Water Supply and Demand / Hydrologic Analysis: Water Quality / Hydrologic Analysis: Floods / Hydrologic Analysis: Low Streamflows and Droughts / Current and Projected Water Use

Description / Table of Contents: Hydrogen may be the most abundant element in the universe, but in science and in nature oxygen has an importance that is disproportionate to its abundance. Human beings tend to take it for granted because it is all around us and we breathe it, but consider the fact that oxygen is so reactive that in a planetary setting it is largely unstable in its elemental state. Were it not for the constant activity of photosynthetic plants and a minor amount of photo dissociation in the upper atmosphere, we would not have an oxygen-bearing atmosphere and we would not be here. Equally, the most important compound of oxygen is water, without which life (in the sense that we know it) could not exist. The role of water in virtually all geologic processes is profound, from formation of ore deposits to igneous petrogenesis to metamorphism to erosion and sedimentation. In planetary science, oxygen has a dual importance. First and foremost is its critical role in so many fundamental Solar System processes. The very nature of the terrestrial planets in our own Solar System would be much different had the oxygen to carbon ratio in the early solar nebula been somewhat lower than it was, because elements such as calcium and iron and titanium would have been locked up during condensation as carbides, sulfides and nitrides and even (in the case of silicon) partly as metals rather than silicates and oxides. Equally, the role of water ice in the evolution of our Solar System is important in the early accretion and growth of the giant planets and especially Jupiter, which exerted a major control over how most of the other planets formed. On a smaller scale, oxygen plays a critical role in the diverse kinds of physical evolution of large rocky planets, because the internal oxidation state strongly influences the formation and evolution of the core, mantle and crust of differentiated planets such as the Earth. Consider that basaltic volcanism may be a nearly universal phenomenon among the evolved terrestrial planets, yet there are basalts and basalts. The basalts of Earth (mostly), Earth's Moon, Vesta (as represented by the HED meteorites) and Mars are all broadly tholeiitic and yet very different from one another, and one of the primary differences is in their relative oxidation states (for that matter, consider the differences between tholeiitic and calc-alkaline magma series on Earth). But there is another way that oxygen has proven to be hugely important in planetary science, and that is as a critical scientific clue to processes and conditions and even sources of materials. Understanding the formation and evolution of our Solar System involves reconstructing processes and events that occurred more than 4.5 Ga ago, and for which the only contemporary examples are occurring hundreds of light years away. It is a detective story in which most of the clues come from the laboratory analysis of the products of those ancient processes and events, especially those that have been preserved nearly unchanged since their formation at the Solar System's birth: meteorites; comets; and interplanetary dust particles. For example, the oxidation state of diverse early Solar System materials ranges from highly oxidized (ferric iron) to so reducing that some silicon exists in the metallic state and refractory lithophile elements such as calcium exist occur in sulfides rather than in silicates or carbonates. These variations reflect highly different environments that existed in different places and at different times. Even more crucial has been the use of oxygen 3-isotope variations, which began almost accidentally in 1973 with an attempt to do oxygen isotope thermometry on high-temperature solar nebula grains (Ca-, Al-rich inclusions) but ended with the remarkable discovery of non-mass-dependent oxygen isotope variations in high-temperature materials from the earliest Solar System. The presolar nebula was found to be very heterogeneous in its isotopic composition, and virtually every different planet and asteroid for which we have samples has a unique oxygen-isotopic fingerprint. The idea for this book originated with Jim Papike, who suggested the idea of a study initiative (and, ultimately, a published volume) focused on the element that is so critically important in so many ways to planetary science. He recognized that oxygen is such a constant theme through all aspects of planetary science that the proposed initiative would serve to bring together scientists from a wide range of disciplines for the kind of cross-cutting dialogue that occurs all too rarely these days. In this sense the Oxygen Initiative is modeled on the Basaltic Volcanism Study Project, which culminated in what remains to this day a hugely important reference volume (Basaltic Volcanism Study Project 1981). After obtaining community input and feedback, primarily through the Curation and Analysis Planning Team for Extraterrestrial Materials (CAPTEM) and the Management Operations Working Group for NASA's Cosmochemistry Program, a team of scientists was assembled who would serve as chapter writing leads, and the initiative was formally proposed to and accepted by the Lunar and Planetary Institute (LPI; Dr. Stephen Mackwell, Director) for sponsorship. A formal proposal was then submitted to and approved by the Mineralogical Society of America to publish the resulting volume in the Reviews in Mineralogy and Geochemistry (RiMG) series. Three open workshops were held as preludes to the book: Oxygen in the Terrestrial Planets, held in Santa Fe, NM July 20-23, 2004; Oxygen in Asteroids and Meteorites, held in Flagstaff, AZ June 2-3, 2005; and Oxygen in Earliest Solar System Materials and Processes (and including the outer planets and comets), held in Gatlinburg, TN September 19-22, 2005. The workshops were each organized around a small number of sessions (typically 4-6), each focusing on a particular topic and consisting of invited talks, shorter contributed talks, and ample time for discussion after each talk. In all of the meetings, the extended discussion periods were lively and animated, often bubbling over into the breaks and later social events. As a consequence of the cross-cutting approach, the final book spans a wide range of fields relating to oxygen, from the stellar nucleosynthesis of oxygen, to its occurrence in the interstellar medium, to the oxidation and isotopic record preserved in 4.56 Ga grains formed at the Solar System's birth, to its abundance and speciation in planets large and small, to its role in the petrologic and physical evolution of the terrestrial planets.

Description / Table of Contents: Contents: 1. Isotopes and radioactivity; 2. The principles o radioactive dating; 3. Radiometric dating methods; 4. Dating by cosmogenic isotopes; 5. Uncertainties and results of radiometric dating; 6. Radiogenic isotope geochemistry; 7. Stable isotope geochemistry; 8. Isotope geology and dynamic reservoir analysis

Description / Table of Contents: Welcher Anteil des Niederschlagswassers gelangt von landwirtschaftlich genutzten Flächen in Bäche und Flüsse? Wie stark und mit welchen Stoffen ist dieses abfließende Wasser belastet? Wie sehen die langfristigen Folgen aus? Das Buch ist eine allgemeine und umfassende Darstellung von kleinräumigen hydrologischen Prozessen im punktuellen cm-Bereich bis hin zum kleinen Einzugsgebiet. Diese abgestimmte Kombination von Theorie, Feldmessung und numerischer Modellierung ist zukunftsweisend für die moderne Hydrologie.

Description / Table of Contents: Knowledge about soil water transport and groundwater renewal rates is crucial for groundwater research and risk assessment. Particularly the impact of preferential flow paths in the unsaturated zone on pollutant transport is an important topic, as it affects the vulnerability of the adjacent aquifer. However, in literature the determination of preferential flow is only partly solved and especially quantification attempts have been rare. Therefore, a new method combining mathematical modelling with hydrological and environmental isotope data was developed to estimate the heterogeneity of the unsaturated transport processes. For this purpose, environmental isotope transport (18O, 2H) was investigated in several lysimeter experiments. A conceptual model was applied, which separates preferential and matrix flow. Both flow components are quantified and their transit time distribution functions are determined to construct specific vulnerability diagrams.Water flow and transport of environmental isotopes through the soil matrix was calculated using both a transient modelling approach solving numerically Richards and Convection-Dispersion-Equation for single porous medium and a lumped parameter approach using the Dispersion Model. The preferential flow component is assumed by piston flow occurring within one week and having no interaction with the soil matrix.For quantification a two component flow approach was applied to the isotope and hydrological data. The mean transit time distribution functions were obtained from the lumped parameter approach and visualized in specific vulnerability diagrams, showing when infiltrating water reaches the groundwater. This method was applied to different lysimeter experiments that were conducted under natural atmospheric conditions. Different lysimeters, filled mostly with sandy soil material, were under investigation to study the impact of soil properties and vegetation on the transport heterogeneity and amount of preferential flow.It was shown that the lumped parameter approach yielded good results modelling the isotope transport in the soils with bare surface. An application to the soils with vegetation required a modification of the classical input function including evapotranspiration and thus considering the infiltration events contributing to the discharge. Additional separation into the single vegetation periods improved the modelling.Preferential flow was observed in all soils and quantified with the two component flow approach. In bare sandy and gravel soils the mean fractions of preferential flow varied between 17 and 30 %. Here, the crucial parameter influencing these fractions was found to be the saturated hydraulic conductivity. In the cropped soils the mean fractions of preferential were dependent on the discharge rate and varied according to the vegetation. Mean fractions of 3 % and 18 % were observed in a loamy sand during intercrop period and cultivation of maize monoculture, respectively. The same soil material but cultivated with crop rotation yielded mean fractions of 14 % during maize, 4 % during winter barley and 15 % during the intercrop vegetation period. In a third experimental setup with sandy soil a mean fraction of 8 % was found.Specific vulnerability diagrams were constructed showing the mean transit time distribution functions of both, preferential and matrix flow. Their patterns were closely related to soil parameters. They can be used as a helpful tool to develop groundwater protection strategies more efficiently.It was shown that the presented method enabled the estimation of transport heterogeneity and the quantification of preferential flow under natural atmospheric conditions in bare and cropped lysimeters using environmental isotope data. Such isotopes are adequate tracer to study the transport processes in the unsaturated zone. It was revealed that experiments with continuous natural application like environmental tracers over long time periods were necessary to cover a broad range of flux variability and to determine transport heterogeneity.

Description / Table of Contents: Contens: Preface: H. S. Wheater, S. Sorooshian and K. D. Sharma; 1. Modelling hydrological processes in arid and semi-arid areas - an introduction H. Wheater; 2. Global precipitation estimation from satellite imagery using artificial neural networks S. Sorooshian, K.-L. Hsu, B. Imam and Y. Hong; 3. Modelling semi-arid and arid hydrology and water resources - the southern Africa experience D. A. Hughes; 4. Use of the IHACRES rainfall-runoff model in arid and semi-arid regions B. F. W. Croke and A. J. Jakeman; 5. KINEROS2 and the AGWA modelling framework D. J. Semmens, D. C. Goodrich, C. L. Unkrich, R. E. Smith, D. A. Woolhiser and S. N. Miller; 6. A distributed spatial sediment delivery model for arid regions K. D. Sharma; 7. The Modular Modeling System (MMS): a toolbox for water and environmental resources management G. H. Leavesley, S. L. Markstrom, R. J. Viger and L. E. Hay; 8. Calibration, uncertainty and regional analysis of conceptual rainfall-runoff models H. Wheater, T. Wagener and N. McIntyre; 9. Real-time flow forecasting P. C. Young; 10. Real-time flood forecasting - Indian experience R. D. Singh; 11. Groundwater modeling in hard-rock terrain in semi-arid areas: experience from India S. Ahmed, J.-C. Maréchal, E. Ledoux and G. de Marsily;