Many agricultural crops worldwide, especially in semi-arid climates, suffer from iron deficiencies. Among plants sensitive to iron deficiency are apples, avocado, bananas, barley, beans, citrus, cotton, grapes, peanuts, pecans, potatoes, sorghum, soybeans, and numerous ornamental plants. Deficiencies are usually recognized by chlorotic, in new leaves and are typically found among sensitive crops grown in calcareous or yellowed, interveinal areas soils which cover over 30% of the earth's land surface. Iron deficiency may lead, in extreme cases, to complete crop failure. In intensive agriculture on calcareous soils, iron often becomes a major limiting nutrient for optimal crop production, thus, correction of iron deficiency is required. Various chemicals and practices are available. They are, however, costly and do not always result in a complete remedy of the deficiency. Crucial questions relative to the cost-benefit equation such as the recovery rate of plants and the long-term fertilizing effect have not yet been resolved. The complexity of iron nutrition problems requires an understanding of the chemistry of iron oxides in soils, of the chemistry of both natural and synthetic chelates, of rhizosphere microbiology and biochemistry, and of the physiological involvement of the plant in iron uptake and transport.
Any numerical subsurface model is comprised of three components: a theoretical basis to translate our understanding phenomena into partial differential equations and boundary conditions, a numerical method to approximate these governing equations and implement the boundary conditions, and a computer implementation to generate a generic code for research as well as for practical applications. Computational Subsurface Hydrology: Reactions, Transport, and Fate is organized around these themes. The fundamental processes occurring in subsurface media are rigorously integrated into governing equations using the Reynolds transport theorem and interactions of these processes with the surrounding media are sophisticatedly cast into various types of boundary conditions using physical reasoning. A variety of numerical methods to deal with reactive chemical transport are covered in Computational Subsurface Hydrology: Reactions, Transport, and Fate with a particular emphasis on the adaptive local grid refinement and peak capture using the Lagrangian-Eulerian approach. The topics on coupled fluid flows and reactive chemical transport are unique contributions of this book. They serve as a reference for research as well as for practical applications with a computer code that can be purchased from the author. Four computer codes to simulate vertically integrated horizontal solute transport (LEMA), contaminant transport in moving phreatic aquifers in three dimensions (3DLEMA), solute transport in variably saturated flows in two dimensions (LEWASTE), and solute transport under variably saturated flows in three dimensions (3DLEWASTE) are covered. These four computer codes are designed for generic applications to both research and practical problems. They could be used to simulate most of the practical, real-world field problems. Reactive chemical transport and its coupling with fluid flows are unique features in this book. Theories, numerical implementations, and example problems of coupled reactive transport and flows in variably saturated media are presented. A generic computer code, HYDROGEOCHEM 3.0, is developed. A total of eight example problems are used to illustrate the application of the computational model. These problems are intended to serve as examples for setting up a variety of simulations that one may encounter in research and field-site applications. Computational Subsurface Hydrology: Reactions, Transport, and Fate offers practicing engineers and scientists a theoretical background, numerical methods, and computer codes for modeling contaminant transport in subsurface media. It also serves as a textbook for senior and graduate course on reactive chemical transport in subsurface media in disciplines such as civil and environmental engineering, agricultural engineering, geosciences, soil sciences, and chemical engineering. Computational Subsurface Hydrology: Reactions, Transport, and Fate presents a systematic derivation of governing equations and boundary conditions of subsurface contaminant transport as well as reaction-based geochemical and biochemical processes. It discusses a variety of numerical methods for moving sharp-front problems, expounds detail procedures of constructing Lagrangian-Eulerian finite element methods, and describes precise implementation of computer codes as they are applied to subsurface contaminant transport and biogeochemical reactions.
In the history of the International Plant Nutrition Colloquium from its first meeting in 1954, this meeting, the 13th Colloquium, is the first to be held in Asia and will be the last in the 20th century. The 20th century has seen huge changes in the number and activities of mankind. Our population has increased from around 1. 7 billion to more than 5. 8 billion and technological innovations have completely altered our way of living. As a consequence of such rapid change, we are facing many problems including changes in our environment of a global scale. But, while food shortage has been a serious concern to mankind throughout our history, serious food shortages in the 20th century have been confined to limited times and areas. As Lester Brown discusses in this volume, farmers have increased food production heroically on demand. We, the plant nutritionists should be proud of our support to the world's farmers which has helped them make their achievement possible. During the 20th century, the science of plant nutrition also has achieved great progress as described by Jack Loneragan; it became established as a discipline firmly based in science, defined the chemical elements supporting plant growth, and has contributed to improvements in plant production and environmental quality, as readers will find in many contributions in this volume.
The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.
Iron is a major constituent of the earth crust. However, under alkaline conditions commonly found in arid and semi-arid environments iron becomes unavailable to plants. When plants are affected by a shortage of iron their leaves become yellow (chlorotic), and both plant growth and crop yield are reduced. The roots of plants affected by iron deficiency may develop a series of responses directed to improve iron uptake, such as increased proton excretion and iron reduction capabilities or excretion of iron chela tors called siderophores. Iron deficiency affects major crops worldwide, including some of major economic importance such as fruit trees and others. Correction of iron deficiency is usually implemented through costly application of synthetic chelates. Since these correction methods are very expensive, the competitivity of farmers is often reduced and iron deficiency may become a limiting factor for the maintenance, introduction or expansion of some crops. In spite of the many years devoted to the study of iron deficiency, the knowledge of iron deficiency in soils and plants is still fragmentary in many aspects. We have only incomplete information on the processes at the molecular level that make some plant species and cultivars unable to take and utilize iron from the soil, whereas other plants grow satisfactorily under the same conditions.
Coordination chemistry is the study of compounds formed between metal ions and other neutral or negatively charged molecules. Coordination chemistry includes areas of inorganic solid state chemistry, organometallic chemistry and bioinorganic chemistry, as well as applications to analytical chemistry, catalysis, industrial chemistry and materials science.
Here is an up-to-date presentation of metal speciation in soils, sediments, and water by specialists in analytical chemistry, environmental engineering, oceanography, nutrition, and soil chemistry. fate and effects-measurements-and modeling-are the major themes in this book, with overviews and examples of the significance of metal speciation to solving environmental problems, and recommendations for additional research areas. This new reference discusses separation methods, extraction techniques; bioavailability as related to humans, plants, and aquatic organisms; applications showing importance of speciation in groundwater; industrial waste treatment systems, marines and lakes, solid-solution interface; fate of organic pollutants; nature of surfaces; binding of metals to oxides and sediments (dissolved and particulate matter); interpretations of reactions in multi-ligand systems.
FUNDAMENTALS OF TURFGRASS MANAGEMENT THE PREMIER TURFGRASS MANAGEMENT HANDBOOK—UPDATED AND EXPANDED Fundamentals of Turfgrass Management is the longstanding authority on all aspects of the science and practices behind world-class turfgrass care. This fully revised Fifth Edition comes enriched by two new authors who share their cutting-edge research and real-world expertise on such topics as growth, soil testing, nutrition, herbicides, insecticides, and fungicides. Coverage throughout is refreshed with new illustrations and charts, as well as: Expanded coverage on professional lawn care programs, including cool-season and warm-season turfgrasses, establishing methods and costs, cultivation, sand topdressing, and more Enhanced material on the most up-to-date thinking and practices in weed management Brand-new chapters on the environmental, economic, and quality-of-life benefits of well-maintained turf, as well as the influence of light on turf health Whether you’re earning a degree or a paycheck, Fundamentals of Turfgrass Management, Fifth Edition remains the most complete, respected guidebook of solutions for developing and maintaining the finest-standards of turfgrass.
