What Is Photosynthesis?
Photosynthesis is the basic process required for plant growth, it is the conversion of sunlight, carbon dioxide and water into sugar and oxygen. It is the most important process on earth with all plants and animals depending on it for survival. The end result is the release of oxygen into the atmosphere and the storage of sugar in the plant (Figure 1). 
Figure 1: Photosynthesis process showing the conversion of sunlight, carbon
dioxide and water into oxygen and sugar (1).
How Can I Influence Photosynthesis?
As a farmer you can influence the rate at which the photosynthesis process occurs through enhancement of the soil in which plants grow and by carefully cconsidering the types of plants to grow. Enhancing the soil involves balancing the soils physical, chemical and biological properties for optimal plant growth. Selecting the type of plant to grow involves the correct selection of species depending on soil type, fertility, drainage, livestock requirements, water use efficiency (WUE) and grazing management.
The amount of sunlight plants receive can be regulated by grazing management. For example if pastures are allowed to grow tall often species such as clovers are shaded out; thereby reducing nitrogen cycling and photosynthetic output. Water can be increased in the soil by irrigation or by management practices which limit evaporation, such as reduced cultivation and the retention of organic matter. These management practices aid in increasing the amount of water available to plants and subsequently enhance photosynthesis.
Farm management practices influence the rate of photosynthesis and can impact on soil fertility, structure, pH, organic matter and therefore productivity. Practices such as reduced cultivation, flexible grazing, pasture and crop rotations, and retention of organic matter, can all increase soil health and therefore plant growth. Decisions on which farm management practices to implement should always take into account the impact that they will have on the photosynthesic process. The level of output from this process is one of the key drivers for a successful farming business.
Are You Interested In Enhancing Photosynthesis On Your Farm?
To understand the differences between crops and pastures and to choose the best option for your farm read: An Introduction to Crops and Pasture for Small Farms.
Notes
1. Photosynthesis, Retrieved 1st March 2008 from http://grapevine.net.au/~grunwald/une/KLAs/science/photosynthesis.html
Glossary
Photosynthesis: Conversion of light + carbon dioxide + water = sugar + oxygen.
Cultivation: Preparation of the soil by tilling.
Organic Matter: Animal and plant remains at various stages of decay.
pH: Strength of acidity or alkalinity in the soil.
Plant Water Use Efficiency: A measure of a plants ability to convert water into dry matter.
By Charlton Roberts B.Frm.Mgt (Agronomist)
