Introduction
Plants provide most of the
nutrients which people and animals need to live. Plants get the nutrients
they need from the soil and the air. Plants absorb these nutrients and
convert them into forms useful to animals and people.
Crop growth is most efficient
when the nutrients needed by the plants are supplied to the plants in
the right amount and at the right time during their growth cycle. Soils
supply most of the nutrients that plants need. However many times soils
need a recharge of some of these nutrients. This recharge can be provided
commercial fertilizers, manures, and other organic sources (plant residue,
etc.) This additional supply of nutrients can be essential for plant
growth and also can be an expensive part of crop production.
Florida
agriculture is a multibillion dollar industry adding $20 billion to
Florida's economy. Florida has over 40,000 commercial farmers. They
are among the most productive in the world using a little more than
10 million of the state's 35 million acresto produce more than 35 billion
pounds of food, andmore than 1.5 million tons of livestock feed. Florida
farmers employed an average of 57,000 farm workers monthly in 1998.
Florida has maintained its position as the nation's No. 9 ranked agriculture
state with record sales of $6.686 billion in 1998. Florida is the nation's
No. 1 citrus producing state, ranks No. 2 in the production of vegetables
and horticulture products, and No. 4 in all crops.
Successful crop
production depends on plant receiving the correct amounts of nutrients
at the appropriate times. The soil supplies many nutrients but additional
nutrients may need to be provided to obtain maximum crop yield. These
nutrients can be supplied from soil amendments in the form of fertilizers,
manures, and other organic sources.
Nutrients must be managed
wisely to preserve the quality of the soil, water and air. Over time
poor nutrient management can impair the land's ability to produce crops.
Nutrient management is a critical part of maintaining Florida's land.
Applying too few or an excess of nutrients is not good for the land
or for the farmer. Too little nutrients cause yield and profits to drop.
Applying more nutrients than the crop can use increases the costs of
production and decreases profits. Too much nitrogen increases the risk
of nitrate-nitrogen leaching from the soil, polluting our groundwater
resources. The excess nutrients can also be carried away by rainfall
runoff to nearby streams and lakes. Surface waters can be polluted by
sediments and nutrients attached to these sediments.
What
are Nutrients?
Nutrients are chemical elements
needed by plants during their life cycles. Nutrients are present in
water, the air, and in soils. Six nutrients are required by plants in
large amounts. These nutrients are known as macronutrients. Three of
these macronutrients are the most common elements in plants: carbon,
hydrogen and oxygen. These elements are obtained through the water and
air. The other three macronutrients: nitrogen, phosphorus and potassium
are naturally present in soil in inorganic forms, as the result of the
weathering of soil minerals.
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Macronutrients
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Carbon
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Hydrogen
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Oxygen
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Nitrogen
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Phosphorus
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Potassium
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There are other nutrients
required in very small amounts, but are essential in the life cycle
of the plant. These are called micronutrients.
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Micronutrients
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Boron
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Calcium
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Chlorine
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Cobalt
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Copper
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Iron
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Magnesium
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Manganese
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Molybdenum
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Silicon
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Sodium
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Sulfur
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Vanadium
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Zinc
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More information on macronutrients
and micronutrients is available on the Basic Soil Fertility web pages.
Basic
Soil Fertility
Nitrogen Cycle
Phosphorus Cycle
What
is Nutrient Management?
Nutrient
Management Plans
