Quantifying and Modeling Soil Structure Dynamics emphasizes a systems approach to how soil structure changes in response to inputs and to the environment. Soil structure is a dynamic, complex system affected by tillage, wheel traffic, roots, soil life, shrink–swell, and freeze–thaw. In turn, soil structure affects root growth and function, soil fauna, solute transport, water infiltration, gas exchange, thermal and electrical conductivities, traffic bearing capacity, and more. Ignoring soil structure or viewing it as “static” can lead to poor predictions and management. Readers will especially appreciate the description of soil structure influence on endpoints, such as environmental contamination and efficient water use, and how models should be adjusted to include dynamic soil structure components for accurate outputs.
Quantifying and Managing Soil Functions in Earth's Critical Zone: Combining Experimentation and Mathematical Modelling, Volume 142, the latest in the Advances in Agronomy series continues its reputation as a leading reference and first-rate source for the latest research in agronomy. Each volume contains an eclectic group of reviews by leading scientists throughout the world. Five volumes are published yearly, ensuring that the authors' contributions are disseminated to the readership in a timely manner. As always, the subjects covered are varied and exemplary of the myriad of subject matter dealt with by this long-running serial. - Includes numerous, timely, state-of-the-art reviews on the latest advancements in agronomy - Features distinguished, well recognized authors from around the world - Builds upon this venerable and iconic review series - Covers the extensive variety and breadth of subject matter in the crop and soil sciences
Methodology for defining sustainable land management practices is increasingly needed to overcome environmental problems and to maintain production potentials. From the large amount of definitions for sustainable management the following was used here: "Sustainable land management combines technologies, policies and activities aimed at integrating socio- economic principles with enviromnental concerns so as to simultaneously: (i) maintain or enhance production and services; (ii) reduce the level of production risk; (iii) protect the potential of natural resources and prevent degradation of soil and water quality; (iv) be economically viable and (v) socially acceptable". Indicators to quantify sustainability are used to analyse the effects of different management types on the soil structure within one soil series in the Netherlands, a loamy, mixed, mesic, Typic Fluvaquent. It is logical to concentrate on soil structure when evaluating and comparing the effects of different management practices as they reflect management practices at an integrated level. Comparison was focused on three soil structure types, formed by different management practices. (i) A biodynamic system (Bio) where no chemical crop protection or commercial fertiliser has been applied since 1924. Animal manure and a crop rotation system with clover are intended to supply the required nutrients. (ii) A conventional system (Conv) representing a management system that is most common in the region. (iii) A system which has been permanently meadow since 1947 (Perm). The biodynamic and conventional system were compared by converting "static" soil parameters, like organic matter content, bulk density, hydraulic characteristics, into a "dynamic" assessment by using a simulation model to calculate water-limlited productivity. A thorough soil characterisation was made, including morphological and physical characterisation as well as monitoring of soil water contents and groundwater levels. Results of the comparison between simulated and measured moisture contents were such that the model was considered to be adequately validated. The simulated water-limited productivity for potatoes was significantly higher for the biodynamic system, indicating a favourable effect of the higher organic matter content. Modern mechanised agricultural practices require soils to be able to be subjected to tillage and traffic, without adverse effects on soil structure. Threshold values for workability and trafficability were obtained for the three management types. Workability by the Atterberg test, trafficability by penetrometer measurements and an additional field-traffic experiment. Threshold values for Conv were most favourable, i.e. during relatively wet conditions Conv could still be tilled and trafficked. Periods of workability and trafficability were obtained by combining measured threshold values with simulated moisture contents. Conv had the longest workable and trafficable period in a year followed by Perm and Bio, respectively. Soil survey could focus in future on defining sustainable forms of landuse, considering that soils within one soil series are not similar. Farm management information combined with quantifying the associated soil structure types by simulation models, can form the basis for defining sustainable management systems for the soil series being studied. As many soil surveys are completed all over the world, the proposed procedure appears to be a worthwhile continuation of the rich tradition of soil survey research.
Gregory Tsinker brings his extensive knowledge of structural engineering and geotechnical design to his translation of George E. Lazebnik's work on soil-structure interaction. Monitoring of Soil-Structure Interaction is aimed at professional geotechnical and foundation engineers who deal with soil-foundation interaction, soil pressure distribution, or ground monitoring instruments. This book will incorporate original data and emphasize practical, mathematical models for measuring soil pressure on the foundations of a structure. Readers will be able to compare their calibrated measurements to the data presented in the book.
This book describes how a number of different methods of analysis and modelling, including the boundary element method, the finite element method, and a range of classical methods, are used to answer some of the questions associated with soil-structure interaction.
For the last couple of decades it has been recognized that the foundation material on which a structure is constructed may interact dynamically with the structure during its response to dynamic excitation to the extent that the stresses and deflections in the system are modified from the values that would have been developed if it had been on a rigid foundation. This phenomenon is examined in detail in the book. The basic solutions are examined in time and frequency domains and finite element and boundary element solutions compared. Experimental investigations aimed at correlation and verification with theory are described in detail. A wide variety of SSI problems may be formulated and solved approximately using simplified models in lieu of rigorous procedures; the book gives a good overview of these methods. A feature which often lacks in other texts on the subject is the way in which dynamic behavior of soil can be modeled. Two contributors have addressed this problem from the computational and physical characterization viewpoints. The book illustrates practical areas with the analysis of tunnel linings and stiffness and damping of pile groups. Finally, design code provisions and derivation of design input motions complete this thorough overview of SSI in conventional engineering practice. Taken in its entirety the book, authored by fifteen well known experts, gives an in-depth review of soil-structure interaction across a broad spectrum of aspects usually not covered in a single volume. It should be a readily useable reference for the research worker as well as the advance level practitioner. (abstract) This book treats the dynamic soil-structure interaction phenomenon across a broad spectrum of aspects ranging from basic theory, simplified and rigorous solution techniques and their comparisons as well as successes in predicting experimentally recorded measurements. Dynamic soil behavior and practical problems are given thorough coverage. It is intended to serve both as a readily understandable reference work for the researcher and the advanced-level practitioner.
In order to build consensus on methods to measure and model soil carbon stocks and stock changes, the Steering Committee of the Livestock Environmental Assessment and Performance (LEAP) Partnership mandated a task force to develop this scoping analysis and pave the way towards the formation of the LEAP Tecnical Advisory Group on soil carbon stock changes. Soil carbon sequestration and storage in grasslands offers a significant potential to compensate for GHG emissions from livestock, but the lack of consensus on the appropriate methodologies to account for soil carbon stock changes hinders robust and standardized assessments. In this report, we reviewed several published soil organic carbon (SOC) models, and evaluated their aptitude to combine them with life cycle assessments (LCAs). Among contentious issues, the most relevant are: a) the lack of universal models, b) the uneven data availability, comparability and quality between countries and regions, and c) the difficulty to match measurable SOC fractions with those determined by the models. Taking this into account, a tiered approach is proposed, according to the availability of original data to run the models. The use of IPCC carbon (C) accounting system appears to be the simplest approach suitable to countries with scarcity of original C data. Conversely, more complex models such as Century (Parton 1987, 1988) or Roth C (Smith 1998) are likely to perform better and give less uncertainty when original input data are easily available.
Soil organic matter (SOM) represents a major pool of carbon within the biosphere, roughly twice than in atmospheric CO2. SOM models embody our best understanding of soil carbon dynamics and are needed to predict how global environmental change will influence soil carbon stocks. These models are also required for evaluating the likely effectiveness of different mitigation options. The first important step towards systematically evaluating the suitability of SOM models for these purposes is to test their simulations against real data. Since changes in SOM occur slowly, long-term datasets are required. This volume brings together leading SOM model developers and experimentalists to test SOM models using long-term datasets from diverse ecosystems, land uses and climatic zones within the temperate region.
Physical Nonequilibrium in Soils provides cutting-edge knowledge on physical nonequilibrium phenomena in soils, offering unique insight into the complexity of our physical world. With 18 chapters comprising the book, topics cover soil properties fluid properties mechanistic models transfer function geostatistics fractal analysis cellular-automation fluids coupling of physical and chemical nonequilibrium models confirming and quantifying physical nonequilibrium in soils analytical solutions field-scale research environmental impacts.
