Integrated Management of Salt Affected Soils in Agriculture

Incorporation of Soil Salinity Control Methods

Nesreen Houssein Ahmen Abou-Baker, Ebtisam Abdelmohsen El-Dardiry

• Publisher: Academic Press
• Year: 2015
• Print ISBN:
  9780128041659
• eBook ISBN:
  9780128041680
• Topic: Technology & Engineering
• Subtopic: Agronomy
• Index: Technology & Engineering

Integrated Management of Salt Affected Soils in Agriculture is a concise guide to evaluating and addressing soil issues related to saline content. Methods focused, the book combines agricultural and soil-based insights to efficiently remediate salt-affected soil. Environmental stress conditions such as salinity have a devastating impact on plant growth and yield, causing considerable loss to agricultural production worldwide. Soil salinity control prevents soil degradation by salinization  and reclaim already saline soils. This book will help develop the proper management procedures, to solve problems of crop production on salt-affected soils. - Provides both agricultural science and soil science perspectives on soil salinity - Identifies differences in salt-affected soils and appropriate remediation options - Includes methodologies based on existing scenario and targeted outcomes

Chapter 1

Salt-Affected Soil Definition and Types

There are many definitions have been used to explain the salt-affected soils, depending on the concentration of soluble salts, pH value, exchangeable sodium percentage, and sodium adsorption ratio. Generally, salt-affected soil is soil that is not suitable for plant growth. I want to explain that this chapter is introductory, just for identifying salt affected soils and its types before the main subject.

Keywords

Salt-affected soil; definition; types; saline; sodic

1.1 Salt-Affected Soils Definition

Different types of physical, chemical, and/or biological land degradation processes (e.g., compaction, inorganic/organic contamination, diminished microbial activity/diversity), mostly under excessive anthropogenic pressures during the last century, have resulted in serious consequences to global natural resources. Among them, soil salinization, arising from either natural or human-induced causes, led to an increase in concentration of dissolved salts in the soil profile to a level that impairs food production, environmental health, and socioeconomic well-being (Ondrasek et al., 2011).

Wind-transported materials from soil or lake surfaces are another source of salts. Application of fertilizers and soil amendments, poor quality irrigation water and capillary rise of shallow saline groundwater, insufficient water application, and insufficient drainage can all contribute to the salinization of the soil layers. Even seawater intrusion onto land, which is a growing problem as sea levels rise in many parts of the world, can deposit a large amount of salts in soils of coastal lands (FAO, 2005; Rengasamy, 2010).

1.2 Types of Salt-Affected Soils

The categories are defined in soil classification literature by the Natural Resources Conservation Service (NRCS) (Table 1.1). EC, electrical conductivity; SAR, sodium adsorption ratio; ESP, exchangeable sodium percentage. Three general categories of salt-affected soils have been identified for management purposes (FAO, 2005, 2008; Horneck et al., 2007; Waskom et al., 2014). Figure 1.1 illustrates a salinized patch in a wheat crop.

• Saline soils: Salt problems in general

• Sodic soils: Sodium problems

• Saline–sodic soils: Problems with sodium and other salts.

Table 1.1

Classification of Salt-Affected Soils

Soil Properties	Non	Saline	Sodic	Saline – Sodic
EC dS/m	Below 4	Above 4	Below 4	Above 4
SAR	Below 13	Below 13	Above 13	Above 13
ESP	Below 15	Below 15	Above 15	Above 15
Soil structure	Flocculated	Flocculated	Dispersed	Flocculated
Soil physical condition	Normal	Normal	Poor	Normal
Symptoms	No adverse effect on soil. Healthy plants	White crust on soil surface. Water-stressed plants. Leaf tip burn.	Poor drainage. Black powdery residue on soil surface.	Grey-colored soil. Plants showing water stress.

EC: electrical conductivity, SAR: sodium adsorption ratio, ESP: exchangeable sodium percentage.

Figure 1.1 A salinized patch in a wheat crop.

Chapter 2

Features, Nature, and Distribution of Salt-Affected Soils

Salt-affected soils occur under nearly all climatic conditions. However, they are relatively more expansive in the arid and semiarid regions compared to the humid regions. The origin and properties of these soils are also d...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Acknowledgements
• Preface
• Introduction
• Chapter 1. Salt-Affected Soil Definition and Types
• Chapter 2. Features, Nature, and Distribution of Salt-Affected Soils
• Chapter 3. Soil Salinization and Sodification Factors
• Chapter 4. Effect of Salinity on Soil Microorganisms, Plant Growth, and Yield
• Chapter 5. Management and Rehabilitation of Salt-Affected Soils
• Chapter 6. Crop Management on Salt-Affected Soils
• Chapter 7. Mineral and Organic Amendments of Salt-Affected Soils
• Chapter 8. Genetic Engineering and Economic Aspects
• Summary and Conclusions
• References