RESTORING SOIL HEALTH: EFFECTIVENESS OF SHORTAND LONG-TERM CONSERVATION PRACTICES

2018

  • Holly A.S. Dolliver
  • Stella L. Pey
  • Jabez T. Meulemans
  • Taylor M. Groby
  • Paul T. Kivlin
  • Satish C. Gupta
  • Dept. of Plant and Earth Science, Univ. of Wisconsin-River Falls,
  • Dept. of Plant and Earth Science, Univ. of Wisconsin-River Falls
  • Jefferson County, Colorado
  • Dept. of Horticulture, Univ. of Wisconsin-Madison
  • Dept. of Plant and Earth Science, Univ. of Wisconsin-River Falls
  • Dept. of Soil, Water, and Climate, Univ. of Minnesota
Project Media

Soil health is the ability and capacity of soil to function within environments and ecosystems
to promote plant and animal health, sustain biological productivity, and maintain
environmental quality. Intensive agricultural land use has been widely shown to degrade
soil quality and health. Functional and structural integrity of the soil can be improved or
potentially return to pre-disturbance conditions with soil conservation practices. The goal
of this work was to 1.) quantify the effects of land conversion from native vegetation to
agricultural cultivation and 2.) measure the rate and degree of soil recovery from both
short-term (less than 15 years) and long-term (greater than 15 years) soil conservation
practices. Conservation measures ranged from management modifications that maintain
crop productivity including practices such as conservation tillage and cover crops to
removal of sensitive land from crop production through the Conservation Reserve Program
(CRP). A variety of soil physical, chemical, and biological parameters were investigated
including bulk density, aggregate stability, infiltration, total organic carbon, carbon dioxide
flux, and microbial biomass. Results show land conversion slightly impacted (less than
20% change from pre-disturbed condition) aggregate stability, moderately impacted (20-
50% change from pre-disturbed condition) bulk density, total organic carbon, and carbon
dioxide flux, and severely impacted (greater than 50% change from pre-disturbed condition)
infiltration and microbial biomass. Both short and long-term crop management
modifications (cover crops and conservation tillage) showed minimal recovery of soil
quality indicators. CRP enrollment showed some recovery of soil quality indicators in the
short-term with more significant recovery over longer timescales; however, even 30 years
of grassland management was not sufficient to recover all parameters to their pre-disturbed
state. Our findings reinforce the importance of investing in significant long-term conservation
initiatives.