Soil organic matter - the product of on-site biological decomposition - affects the chemical and physical properties of the soil and its overall health. Its composition and breakdown rate affect: the soil structure and porosity; the water infiltration rate and moisture holding capacity of soils; the diversity and biological activity of soil organisms; and plant nutrient availability. This document concentrates on the organic matter dynamics of cropping soils and discusses the circumstances that deplete organic matter and their negative outcomes. It then moves on to more proactive solutions. It reviews a "basket" of practices in order to show how they can increase organic matter content and discusses the land and cropping benefits that then accrue.--Publisher's description.

Soils are affected by human activities, such as industrial, municipal and agriculture, that often result in soil degradation and loss. In order to prevent soil degradation and to rehabilitate the potentials of degraded soils, reliable soil data are the most important prerequisites for the design of appropriate land-use systems and soil management practices as well as for a better understanding of the environment. The availability of reliable information on soil morphology and other characteristics obtained through examination and description of the soil in the field is essential, and the use of a common language is of prime importance. These guidelines, based on the latest internationally accepted systems and classifications, provide a complete procedure for soil description and for collecting field data. To help beginners, some explanatory notes are included as well as keys based on simple test and observations.--Publisher's description.

This publication is a revised and updated version of World Soil Resources Reports No. 84, a technical manual for soil scientists and correlators, designed to facilitate the exchange of information and experience related to soil resources, their use and management. The document provides a framework for international soil classification and an agreed common scientific language to enhance communication across disciplines using soil information. It contains definitions and diagnostic criteria to recognize soil horizons, properties and materials and gives rules and guidelines for classifying and subdividing soil reference groups. Published also in Spanish and Arabic.

Origin,classification and distribution of salt-affected soils;saline soils and their management;sodic soils and their management;salinity problems of the dryland regions;water quality and crop production;socio-economic considerations in reclamation and management of salt-affectedsoils;