Author: J. C. Hoogland
Publisher:
ISBN:
Category : Food crops
Languages : en
Pages : 14

View

Book Description

Author: R.A. Feddes
Publisher: Springer Science & Business Media
ISBN: 9781402029189
Category : Science
Languages : en
Pages : 392

View

Book Description
Mankind has manipulated the quantity and quality of soil water for millennia. Food production was massively increased through fertilization, irrigation and drainage. But malpractice also caused degradation of immense areas of once fertile land, rendering it totally unproductive for many generations. In populated areas, the pollutant load ever more often exceeds the soil’s capacity for buffering and retention, and large volumes of potable groundwater have been polluted or are threatened to be polluted in the foreseeable future. In the past decades, the role of soil water in climate patterns has been recognized but not yet fully understood. The soil-science community responded to this diversity of issues by developing numerical models to simulate the behavior of water and solutes in soils. These models helped improve our understanding of unsaturated-zone processes and develop sustainable land-management practices. Aimed at professional soil scientists, soil-water modelers, irrigation engineers etc., this book discusses our progress in soil-water modeling. Top scientists present case studies, overviews and analyses of strengths, weaknesses, opportunities and threats related to soil-water modeling. The contributions cover a wide range of spatial scales, and discuss fundamental aspects of unsaturated-zone modeling as well as issues related to the application of models to real-world problems.

Author: Manoj K. Shukla
Publisher: CRC Press
ISBN: 0429555393
Category : Science
Languages : en
Pages : 492

View

Book Description
Designed for undergraduate and graduate students interested in learning basic soil physics and its application to environment, soil health, water quality and productivity, this book provides readers with a clear coverage of the basic principles of water and solute transport through vadose zone, the theory behind transport and step-by-step guidance on how to use current computer models in the public domain along with soil erosion and contaminant remediation. Students will develop a deeper understanding of the fundamental processes within the soil profile that control water infiltration, redistribution, evapotranspiration, drainage, and erosion. The updated second edition features one new chapter, highlighting new problems, new computer models, and remediation. Features Serves as the most up-to-date textbook on soil physics available. Includes one new chapter and many new numerical examples. Offers mathematical descriptions supported by simplified explanations. Provides case studies and step-by-step guidance on how to use public domain computer models. Covers all principles and processes in an easy-to-understand format with numerous illustrations and sample problems. Students studying in the fields of Soil Science, Environment Science, Natural Resources, Agriculture Engineering, Civil Engineering, Environmental Engineering, Range Sciences, Horticulture, Crop Sciences, and Forestry, will find this book provides a solid foundation for their studies. Professionals, researchers, academicians, and companies working in fields related to Environmental Science, Soil Physics, Hydrology, and Irrigation, will find this book is a great reference tool as it is the most up to date in its field.

Author: Michael Raviv
Publisher: Elsevier
ISBN: 0080556426
Category : Science
Languages : en
Pages : 625

View

Book Description
Plant production in hydroponics and soilless culture is rapidly expanding throughout the world, raising a great interest in the scientific community. For the first time in an authoritative reference book, authors cover both theoretical and practical aspects of hydroponics (growing plants without the use of soil). This reference book covers the state-of-the-art in this area, while offering a clear view of supplying plants with nutrients other than soil. Soilless Culture provides the reader with an understanding of the properties of the various soiless media and how these properties affect plant performance in relation to basic horticultural operations, such as irrigation and fertilization. This book is ideal for agronomists, horticulturalists, greenhouse and nursery managers, extension specialists, and people involved with the production of plants. * Comprehensive discussion of hydroponic systems, irrigation, and control measures allows readers to achieve optimal performance* State-of-the-art book on all theoretical aspects of hydroponics and soilless culture including a thorough description of the root system, its functions and limitation posed by restricted root volume* Critical and updated reviews of current analytical methods and how to translate their results to irrigation and fertilization practices * Definitive chapters on recycled, no-discharge systems including salinity and nutrition management and pathogen eradication * Up-to-date description of all important types of growing media

Author: J. Glinski
Publisher: CRC Press
ISBN: 1351093606
Category : Science
Languages : en
Pages : 311

View

Book Description
This book is a specialized monograph on soil physical conditions and root-system relations. It attempts to explain the importance of physical properties of soil by showing how they affect root growth and functions; and on the other hand, how roots themselves change their environment. Emphasis is placed on the interactive effects of soil physical factors. An attempt has been made to analyze the possibilities of the root system‘s modification by both soil and plant management.The book is addressed to research workers and advanced students in soil and plant sciences and may also be of interest to agronomists and related specialists.

Author: Herman J.P. Eijsackers
Publisher: Springer Science & Business Media
ISBN: 9401120080
Category : Science
Languages : en
Pages : 810

View

Book Description
Increasing awareness of the irreversible and long-lasting impacts of deterioration and pollution of soils and sediments has had an important influence on environmental policies and research in the last decade. The complexity of the soil and sediment systems and its processes cannot be tackled properly unless scientists from different disciplines work together. With this in mind, a number of multidisciplinary soil research programmes have been started in various European countries. They involve different disciplinary approaches and they aim at different fields of application: agriculture, land use and town and country planning, drinking water supply, nature management. The results that are now appearing need to be integrated in a scientifically sound and useful way. The first European Conference on Integrated Research for Soil and Sediment Protection and Remediation was intended to foster this. The volume contains the edited and selected proceedings of this Conference.

Author: Parikshit Verma
Publisher:
ISBN:
Category :
Languages : en
Pages : 234

View

Book Description
Root water uptake by plants mediates the exchange of water, carbon and energy between land surface and atmosphere and is important in hydrological, climatological, agricultural and ecological studies. Field measurements show that root water uptake could be significantly affected by root water compensation and hydraulic redistribution. We thus use a root water uptake model able to describe these two mechanisms and show their importance when vegetation is growing in shallow water-table environments or duplex soils. The model is based on the Richards equation for the water-flow in soils, with a term for root water uptake being a function of the water potential difference between root xylem and the soil. We describe the flow in the xylem using the Darcy's equation.The model is used in three studies aimed at highlighting the role that root water compensation and hydraulic redistribution might have on the overall root water uptake. In the first study, the model in one dimension is applied to a site near Sydney, Australia, to investigate how native trees growing on duplex soils are able to sustain transpiration rate despite long periods with little or no rain. The model was able to reproduce sap-flux data and the pattern of soil, root and leaf water potential for several months. Scenarios with different root depths showed that trees were able to adjust their water-uptake rates from different soil layers based on soil moisture availability; thus, root water compensation appears to be a key mechanism to maintain sustained transpiration rates. In a second study we investigated the contribution of root water compensation and hydraulic redistribution to root water uptake in shallow water-table environments. We compared the results of our model with a more commonly used root water uptake model. In the third study, we extended the 1D-model to two dimensions, thereby being able to simulate horizontal hydraulic redistribution and the interaction between species with different root systems. In the 2D-model, the roots were assumed to be a continuum in soil and the root systems were described in terms of xylem conductivity fields. Scenarios are presented to show that the 2D-model is able to reproduce observed flow patterns through roots in parts of the soil with different degrees of moisture. The studies presented in this thesis show the further development and use of a modeling approach that is gaining increasing interest in the recent literature. These studies present a realistic description of the role that root water compensation and hydraulic redistribution play in plant water use. The 2D-model introduces a representation of the root system that allows for modelling vertical (hydraulic lift) and horizontal hydraulic redistribution of water in soil, and an efficient description of the interaction between species with different root systems.

Author: A. L. Van Wijk
Publisher: CRC Press
ISBN: 1000108341
Category : Technology & Engineering
Languages : en
Pages : 334

View

Book Description
This book is an outcome of the symposium on agricultural water management in Netherlands and discusses the methods that leads to cost effective but environmentally acceptable techniques. The book covers following topics: drainage and reclamation of soil and effect of drainage on agriculture.

Author: S.M.P. Smets
Publisher: IWMI
ISBN:
Category :
Languages : en
Pages : 148

View

Book Description

Author: D.G. Toll
Publisher: CRC Press
ISBN: 0203884434
Category : Science
Languages : en
Pages : 1008

View

Book Description
Unsaturated Soils: Advances in Geo-Engineering comprises 136 contributions from leading international researchers and practitioners, presented at the First European Conference on Unsaturated Soils (Durham, UK, 2-4 July 2008). The papers report on the latest advances in geo-engineering aspects of unsaturated soils. It is the first collection to focu