Systems

Originally written February 1, 2006 | Last updated February 23, 2014

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What is an ecosystem?

An ecosystem is a geographic location on the earth's surface where energy and nutrients are captured and transformed by plants, animals and microbes.

An ecosystem can be as large as the planet or as small as a clump of soil. Within each, complex communities of organisms interact to transform energy from one form to another, and to take up and transform nutrients such as nitrogen and phosphorus.

Effective ecological management of field cropping systems is based on understanding farms and fields as ecosystems.

Farms are human-managed ecosystems designed to produce as much harvestable biomass (crop yield) as environmental conditions allow.

All crops are grown as part of a cropping system. Even a simple cropping system is quite complex in terms of interactions of the plants with the soils, and with soil organisms and crop pests.

Natural inputs contribute tremendously to a farm's productivity, as do supplemental inputs such as fertilizes and pesticides. As a result farms tend to be more productive than the natural ecosystems they replace.

Primary production is through photosynthesis
and depends upon plant
Energy flow in the field
crop ecosystem
  • photosynthetic efficiency
  • leaf area
  • leaf duration
  • water availability
  • nutrient availability
  • Sun
  • Plants
  • Herbivores
  • Decomposers
  • Carnivores
  • Soil nutrients

Current ecosystem challenges

Crop Rotations

  • Corn following soybean
  • Corn following corn
  • Corn following sod/alfalfa
  • Cover crops following corn silage
  • Specialty/niche systems for crop production
Soil Erosion
  • Wind
  • Water
  • Tillage systems to control erosion
    • Conventional tillage corn and soybean
    • No-till corn and soybean
    • Ridge-till corn
    • Zone-till corn
  • Further reading: Soils of Wisconsin (Hole, Francis Doan, 1913-2002. Soils of Wisconsin. Madison, Wisc.: University of Wisconsin Press, 1976)

Nutrient Cycling

  • Carbon sequestration 
    • "Carbon credits"
    • Conservation and no-till tillage systems
    • Cover crops
  • N-cycle and N-supply situation
    • Allocate fertilizer across all corn acres
    • Take credit for homegrown nitrogen
    • Use alternative sources of nitrogen
    • By-product fertilizers may be available from industries
    • Change crop rotation
    • Use proven crop production practices
  • P-Index for Nutrient management Planning
  • Hypoxia in the Gulf of Mexico
Transgenics and what they mean for agriculture sustainability

Organic corn production systems

Further Reading

To purchase hard copies of these publications, go to The UWEX Learning Store

Management of Wisconsin Soils UWEX Bulletin A3588

Converting CRP Land to Corn: Minimizing Phosphorus Loss UWEX Bulletin A3831

Converting CRP Land to Corn: Minimizing Soil Loss  UWEX Bulletin A3830


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