RELEVANCE OF SOIL MINERALS IN PLANT GROWTH AND DEVELOPMENT
TABLE OF CONTENT
TITLE PAGE- – – – – – – – – i
CERTIFICATION- – – – – – – – ii
DEDICATION- – – – – – – – – iii
ACKNOWLEDGEMENT S- – – – – – – iv
TABLE OF CONTENT- – – – – – – – v-vi
CHAPTER ONE
1.0 Introduction- – – – – – – – 1
1.1 Overview of soil mineral- – – – – – 1
1.2 Uptake process of soil Mineral – – – – – 2-3
CHAPTER TWO
2.1 Factors Affecting Nutrient Availability in the Soil- – – 4-5
2.2 Mechanism of Root Uptake Of Soil Nutrient- – – 5-7
2.3 Types of soil mineral available to plant – – – – 7
2.3.1 Carbon- – – – – – – – – 7
2.3.2 Nitrogen- – – – – – – – – 8-9
2.3.3 Phosphorus- – – – – – – – – 9
2.3.4 Potassium – – — – – – – – – 9-10
2.3.5 Calcium- – – – – – – – – 10-11
2.3.7 Sulfur — – – – – – – – – 11
CHAPTER THREE
3.0 Relevance of soil minerals in plant growth and development- 12
3.1 Major elements- – – – – – – – 12-14
3.2 Trace Elements- – – – – – – – 14-15
3.3 Deficiency and Toxicity- – – – – – – 15-16
CHAPTER FOUR
4.0 Summary and Conclusion- – – – – – 17
4.1 Summary- – – – – – – – – 17
4.2 Conclusion- – – – – – – – – 17-18
References
CHAPTER ONE
1.0 INTRODUCTION
1.1 OVERVIEW OF SOIL MINERAL
Plant require some specific elements from the external environment and these are usually obtained by roots from the soil. The quantities of each element required by plants can be used to define them as being either macro- or micro-nutrients. The elements that are essential for growth serve both structural and biochemical roles in the plant and many have multiple functions.
Soil is a major source of nutrient needed by plants for growth. The three main nutrient are nitrogen (N), phosphorus (p) and potassium (k). together they make up the trio known as NKP. Other important nutrients are calcium, magnesium and sulphur. Plants also need small quantities of iron, manganese, zinc, copper, boron and molybdenum, known as trace elements because only trace are needed by the plant. The role these nutrients play in plant growth is complex.
1.2 UPTAKE PROCESSES OF SOIL MINERAL
Nutrients in the soil are taken up by the plant through its roots and in particular its root hairs. A nutrient element must be located near the root surface; However the supply of nutrients in contact with the root is rapidly depleted within a distance of Ca. 2mm. (Fohse et al., 1991). There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought into contact with plant roots.
- Mass flow of water
- Diffusion within water
- Interception by root growth
All three mechanisms operate simultaneously, but one mechanism or another may be most important for a particular nutrient. Barber et al., (1963) for example, in the soil solution, except when Aluminium over competes calcium on cation exchange sites in very acid soils (PH less than 4). Lawrence et al., (1995) mass flow alone can usually bring sufficient amounts to the rot surface. This movement can take place by mass flow, as when dissolved nutrients are carried along with the soil water flowing toward a root that is actively drawing water form the soil.
In addition, nutrient Ions are diffusion from areas of greater concentration towrd the nutrient depleted areas of lower concentration around the root surface, that process is due to random also called Brownian motio of molecules within a gradient of decreasing concentration. Kramers & Hendrik Anthony (1940) by this means, plants can continue to take up nutrients even at night when water is only slowly absorbed into the roots as transpiration has almost stopped following stomatal closure. Lin et al., (2009).
