The amount of organic matter in the upper 15 cm of soil
in the organic farming systems was approximately 110,000
kg per ha.The soil of the upper 15 cm weighed about 2.2 million
kg per ha.Approximately 41% of the volume of the organic
matter in the organic systems consisted of water,
compared with only 35% in the conventional systems (Sullivan
2002). The amount of water held in both of the organic
systems is estimated at 816,000 liters per ha. The large
amount of soil organic matter present in the organic systems
aided in making the systems more tolerant of droughts,
such as those that occurred in 1999 and other drought
years.
Large amounts of biomass (soil organic matter) are expected
to significantly increase soil biodiversity (Pimentel et
al. 1992,Troeh and Thompson 1993, Lavelle and Spain 2001,
Mader et al. 2002). The arthropods per ha can number from
two million to five million, and earthworms from one million
to five million (Lavelle and Spain 2001,Gray 2003). The microarthropods
and earthworms were reported to be twice as
abundant in organic versus conventional agricultural systems
in Denmark (Hansen et al. 2001). The weight of the
earthworms per ha in agricultural soils can range from 2000
to 4000 kg (Lavelle and Spain 2001). There can be as many as
1000 earthworm and insect holes per m2 of land. Earthworms
and insects are particularly helpful in constructing large
The amount of organic matter in the upper 15 cm of soilin the organic farming systems was approximately 110,000kg per ha.The soil of the upper 15 cm weighed about 2.2 millionkg per ha.Approximately 41% of the volume of the organicmatter in the organic systems consisted of water,compared with only 35% in the conventional systems (Sullivan2002). The amount of water held in both of the organicsystems is estimated at 816,000 liters per ha. The largeamount of soil organic matter present in the organic systemsaided in making the systems more tolerant of droughts,such as those that occurred in 1999 and other droughtyears.Large amounts of biomass (soil organic matter) are expectedto significantly increase soil biodiversity (Pimentel etal. 1992,Troeh and Thompson 1993, Lavelle and Spain 2001,Mader et al. 2002). The arthropods per ha can number fromtwo million to five million, and earthworms from one millionto five million (Lavelle and Spain 2001,Gray 2003). The microarthropodsand earthworms were reported to be twice asabundant in organic versus conventional agricultural systemsin Denmark (Hansen et al. 2001). The weight of theearthworms per ha in agricultural soils can range from 2000to 4000 kg (Lavelle and Spain 2001). There can be as many as1000 earthworm and insect holes per m2 of land. Earthwormsand insects are particularly helpful in constructing large
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