Agriculture Reference
In-Depth Information
4.5 INTENSIFICATION OF ANIMAL AGRICULTURE
AND TRANSLOCATION OF NUTRIENTS
During the past 50 years and continuing today, there has been a dramatic increase
in the concentration of animals into Concentrated Animal Feeding Operations
(CAFOs). Beef animal feedlots with less than 1000 head of capacity comprise the
vast majority of US feedlots but market a relatively small share of fed cattle. In con-
trast, lots with 1000 head or more of capacity comprise less than 5% of total feedlots
but market 80% to 90% of fed cattle (USDA 2012). Feedlots with 32,000 head or
more of capacity market around 40% of fed cattle, and some feedlots have a one-time
capacity of 100,000 or more. Beef animals are usually fed only about 140 days, so
60,000 to 75,000 beef animals are commonly fattened annually in a 30,000-capacity
feedlot. Similarly, dairy cows are becoming increasingly concentrated. In 2000,
10.5% of milk production was from dairy farms with more than 2000 cows, and this
grew to 23.4% by 2006 (MacDonald et al. 2007). Poultry animals have long been
highly concentrated, and swine are also increasingly being concentrated. An even
more important factor is that more and more of these large operations are located
in areas far removed from where most of the grain and other feed stuffs fed to these
animals are produced, so massive amounts of feeds are transported into the area
by trucks and trains. This has led to the translocation of millions of tons of N and
P from areas where crops are produced to areas where animals are fed. Most of the
N and P fed to animals are excreted and remain in the area as manure, and there is
often not enough cropland to efficiently utilize the manure. On average, about 12 Mt
of N and 2 Mt of P have been used as fertilizer every year in the United States for
the past few decades, and approximately 40% of these nutrients are applied to corn
and 40% to 50% of the corn is fed to animals. Because more and more of the corn
fed to animals is being fed in areas far removed from where the corn was grown, and
often in areas where there are limited amounts of cropland, these nutrients are not
being recycled. The 12 Mt of N comes from atmospheric N
2
and the 2 Mt of P comes
from mines. Thus, huge amounts of N and P are added to the environment each year,
some of which damages surface and groundwater supplies and increases greenhouse
gases. The disconnect between the location of nutrients used for production of grain
crops, and where the nutrients ultimately reside in the environment after excretion
by both humans and animals, is a growing and serious concern. In retrospect, it is
clear that there was not enough thought given to the total system as needed, and
this lack of a systems approach is still evident today. Recycling of nutrients should
be a high priority, and this is the foundation of organic farming. Therefore, while
much more attention should be given to the recycling of nutrients, organic farming as
defined by IFOAM (2012) cannot meet the food and fiber needs of the world accord-
ing to many scientists as discussed above. Norman Borlaug, the Nobel Peace Prize
Laureate, credited for saving more human lives than any man in history by being the
father of the “Green Revolution,” saving countless millions of people from hunger
in India and other countries, responded to a reporter that stated that a lot of people
claim organic food is better for human health and the environment than convention-
ally grown food by stating, “That's ridiculous. This shouldn't even be a debate. Even
if you could use all the organic material that you have—the animal manures, the
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