**Palaniswamy Thangavel**

**1**

CO3

2− and HCO3

exchangeable Na+

**Chapter 1**

Prospects

*and Nafees A. Khan*

**1.1 Human, food and plants**

**1.2 Soil salinization: concept and types**

−

(EC), pH, exchangeable sodium (Na+

excess accumulation of varied salts (e.g., cations: Na+

**1. Introduction**

Introductory Chapter: Making

under Salinity – Updates and

Plant Life Easier and Productive

*Naser A. Anjum, Asim Masood, Palaniswamy Thangavel* 

Almost all life forms on the Earth fundamentally depend on plants and/or plantbased (food and non-food) resources. Human being, in particular, are indebted (directly or indirectly) to the diversity of plants for oxygen, food, fuel, fiber, medicines, and even for shelter. Being sessile by nature, plants have to closely interact with the immediate environment (growing conditions comprising air, water, soil, energy/ light) to sustain their own lives and accomplish the aforementioned notable contributions to human life. As an enigmatic, heterogeneous, multiphasic and porous system, soil acts as a natural growth environment/medium for diverse land plants. The health of soil is closely linked with the health of plants and that of their immediate and longterm consumers. Interestingly, 80% of average calorie consumption comes from crop plants grown directly in soil. Hence, healthy soil has been widely argued vital both as a resource for feeding the burgeoning global population via agriculture, and also for

realizing most of the United Nations Sustainable Development Goals [1–5].

The health of soil is being significantly impacted by increased salinization due to

soluble salts (TSS), and total dissolved solids (TDS), soils can be categorized in three major types: saline, sodic and saline-sodic. EC of the saturation paste extract (ECe) is the measure of salinity, whereas the measure of sodicity is the exchangeable sodium (Na+

percentage (ESP) or the sodium adsorption ratio (SAR). Soils can be saline (ECe > 4 dS m−1 (decisiemens per meter)) at 25°C and ESP < 15 (high soluble salts and low

). Based mainly on the soil properties, namely electrical conductivity

; pH 7.0–8.5), sodic (Ece < 4 dS m−1 and ESP > 15; with a high amount

) percent (ESP), Na+

, Ca2+ and Mg2+; anions: Cl−

adsorption ratio (SAR), total

, SO4 2−,

)

Department of Environmental Science, Periyar University, Salem, India
