Irrigated agriculture produces about 40% of all food and fibre on about 16% of all cropped land. As such, irrigated agriculture is a productive user of resources; both in terms of yield per cropped area and in yield per volume of water consumed. Many irrigation projects, however, use (divert or withdraw) much more water than consumed by the crop. The non-consumed fraction of the water may cause a variety of undesirable effects ranging from water-logging and salinity within the irrigated area to downstram water pollution. This book discusses all components of the water balance of an irrigated area; evapotranspiration (Ch.2), effective precipitation (Ch.3) and capillary rise from the groundwater table (Ch.4). Chapter 5 then combines all components into a water management strategy that balances actual evapotranspiration (and thus crop yield) with the groundwater balance of the irrigated area (for a substainable environment). Chapter 6 presents CRIWAR 3.0, a simulation program that combines all water balance components into a single simulation procedure. The chapter describes the use of the CRIWAR software for developing water requirement tables and other useful information based on the selected water management strategy. This version greatly expands upon the capabilities of previously published programs.

Human-induced salinisation is a major threat to the world's land and water resources. Inadequate development of irrigation projects, inefficient irrigation, lack of proper drainage, and environmental mismanagement such as the clearing of native vegetation, are responsible for the loss of millions of hectares of agricultural and grazing land, as well as the misuse of scarce water resources. The first part of this book analyses the problem in the context of the world's population, its climate and its land and water resources. It reviews irrigation methods and crop water requirements, the processes of salinisation, and its management. The second part describes irrigated land, dryland and water-resource salinity problems in 11 countries, which contain approximately 70 per cent of the world's irrigated land. In each case study, background data, environmental conditions and past management practices are given to provide an understanding of why salinity occurs in particular places, and of the management methods employed against it.

Poor land management has degraded vast amounts of land, reduced our ability to produce enough food, and is a major threat to rural livelihoods in many developing countries. This book provides a thorough analysis of the multifaceted impacts of land use on soils. Abundantly illustrated with full-color images, it brings together renowned academics and policy experts to analyze the patterns, driving factors and proximate causes, and the socioeconomic impacts of soil degradation.

The comprehensive and compact presentation in this book is the perfect format for a resource/textbook for undergraduate students in the areas of Agricultural Engineering, Biological Systems Engineering, Bio-Science Engineering, Water Resource Engineering, and Civil & Environmental Engineering. This book will also serve as a reference manual for researchers and extension workers in such diverse fields as agricultural engineering, agronomy, ecology, hydrology, and meteorology.

Population, Land Use, and Environment: Research Directions offers recommendations for future research to improve understanding of how changes in human populations affect the natural environment by means of changes in land use, such as deforestation, urban development, and development of coastal zones. It also features a set of state-of-the-art papers by leading researchers that analyze population-land useenvironment relationships in urban and rural settings in developed and underdeveloped countries and that show how remote sensing and other observational methods are being applied to these issues. This book will serve as a resource for researchers, research funders, and students.