Facts and Myths of Feeding the World with Organic Farming Methods - Principles of Sustainable Soil Management in Agroecosystems - page 103

human waste, the plant residues—and get them back on the soil, you couldn't feed
more than 4 billion people. In addition, if all agriculture were organic, you would
have to increase cropland area dramatically, spreading out into marginal areas and
cutting down millions of acres of forests” (Borlaug 2009).
4.6 INTEGRATING THE USE OF ORGANIC MATERIALS,
BIOLOGICAL PROCESSES, AND CHEMICAL FERTILIZERS
Crop yields, particularly cereals, must continue to increase to support a growing and
more prosperous world population that is demanding more meat, dairy products,
eggs, and other products requiring more animal feeds. At the same time, serious
concerns are increasing about the effect that the heavy use of synthetic nitrogen,
phosphorus fertilizers, and pesticides (Galloway and Cowling 2002; Townsend et
al. 2003; Pimentel et al. 2005; Ladha et al. 2005) is having on the environment and
perceived health issues. While organic production is growing and seen by some as a
solution, most scientists believe that food and fiber needs can only be met by contin-
ued high use of fertilizer and pesticide inputs. The primary question is not whether
high yields can be produced from organic systems. Pimentel et al. (2005) stated that
various organic agricultural technologies have been used for about 6000 years to
make agriculture sustainable while conserving soil, water, energy, and biological
resources. They also reviewed results from 1981 to 2002 of the Rodale Institute farm-
ing systems trial conducted in Kutztown, PA. They concluded that there were many
benefits from organic technologies. Soil organic matter and nitrogen were higher in
the organic farming systems and helped conserve soil and water resources during
drought years. Fossil energy inputs were about 30% lower than for conventionally
produced corn. Labor inputs averaged about 15% higher but were more evenly dis-
tributed over the year. Regarding yields, they concluded that depending on the crop,
soil, and weather conditions, organically managed crop yields on a per-hectare basis
can equal those from conventional agriculture, although it is likely that organic cash
crops cannot be grown as frequently over time because of the dependence on cul-
tural practices to supply nutrients and control pests. In an earlier study conducted in
California, Sean et al. (1999) found that nitrogen deficiency and weed competition
were the two primary problems associated with organic farming. Pimentel et al.
(2005) acknowledged that the favorable geographical soil characteristics present at
the Rodale Institute farm may not be universally applicable.
Unfortunately, there has been too much conflict between people supporting use
of synthetic fertilizers and those that use only organic materials. There are several
reasons this has happened, but it is important that both sides become more fully
informed. Many users of organic products believe that synthetic fertilizers are
anthropogenic substances. Although synthetically fixed ammonia is produced by
human activities, there is absolutely no difference in an NH − ion formed in the soil
from synthetically fixed ammonia and one that is formed from ammonia added with
manure or from biologically fixed nitrogen. Likewise, phosphorus ions taken up by
plants are the same regardless of their source. In contrast, many of the pesticides
used in conventional agriculture are anthropogenic substances, and supporters of
organic foods can make a more valid case for concern. From a nutrient standpoint,