ISSN:
1572-9915
Keywords:
organic agriculture
;
agriculture
;
China
;
energy flow
;
agroecology
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Energy, Environment Protection, Nuclear Power Engineering
,
Ethnic Sciences
Notes:
Abstract The energy flows in a seventeenth century agroecosystem in Jiaxing region of eastern China were analyzed on the basis of historical data. The agroecosystem included cropping, mulberry-silkworm, livestock, and fishing systems. In terms of energy, the agroecosystem was sustainable. Human labor provided all the power with inputs of about 3700 hr per hectare of farmland. Most or 70% of the labor was expended in the cropping system. Human and animal manure provided most of the nutrients for crop and mulberry production. About two-thirds of the total manure was used in crop production and one-third in the mulberry plantations. The only fossil energy input was a few hand tools. Approximately 55% of the grain was consumed directly by local residents, about one-third of the grain was used to make an alcohol drink and produce distillers'grains, which was fed to pigs, and only 2% of the grains were exported outside the agroecosystem. About two-thirds of the harvested crop residues were used as household fuel, while the remainder was returned to the field as an organic fertilizer. Pork accounted for 85% and silk cocoons 14% of the total animal products produced. Even though the agroecosystem was generally sustainable in terms of energy, the major environmental problem was that two-thirds of the harvested crop residues were used for household fuel. This reduced nutrient cycling in the system. Insufficient land was available to produce fuelwood;thus, crop residues were the primary source of fuel for the people.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00889208