Agriculture Reference
In-Depth Information
Experimental investigations at the Kellogg Biological Station Long-Term
Ecological Research site (KBS LTER) provide insights into the productivity of
different row-crop production systems vis-à-vis ecosystem services such as car-
bon (C) sequestration, nutrient cycling, pest protection, and energy efficiency, and
consequent impacts on soil and water resources. Such insights could be valuable
for guiding agriculture through the coming challenges of feeding, clothing, and
powering a growing global population with finite natural resources and uncertain
trajectories of environmental change.
In this chapter, we report on key agroecosystem performance and ecosystem ser-
vice indicators measured in KBS cropping system experiments. We include results
from both the Main Cropping System Experiment (MCSE) as well as the Living
Field Laboratory Experiment (LFL) (Robertson and Hamilton 2015, Chapter 1 in
this volume). Alternative cropping systems in these experiments include reduced
soil disturbance and complex mixtures of grain crops and winter cover crops such
as red clover (
Trifolium pretense
L.) and annual rye (
Secale cereal
L.) that are
grown in between grain crops to conserve resources and increase soil fertility.
Cover crops are included in many of the KBS LTER agricultural systems because
cover crops promote a host of supporting ecosystem services related to soil organic
matter, nutrient cycling, water quality, and soil conservation (Snapp et al. 2005,
MEA 2005).
Quantifying the benefits and potential trade-offs associated with cover crops
and other agricultural practices that maintain or enhance ecosystem services will
provide insights for policy makers, land managers, and agricultural advisors. Over
two decades of experimentation at KBS provide a unique opportunity to test how a
variety of practices—reducing external inputs, no-tillage production, and enhanc-
ing plant and residue diversity—affect grain production and ecosystem services,
including supporting and regulating ecosystem services.
Agriculture in Michigan
Historical trends in southern Michigan, the location of the KBS LTER, show that
agrarian systems have changed dramatically over the last two centuries (Gage et
al. 2015, Chapter 4 in this volume). The anthropological record across the upper
U.S. Midwest suggests a mosaic of land uses prior to European settlement. Highly
diverse horticultural systems were practiced in specific locales, intermixed with
low-intensity forest and grassland management (Rudy et al. 2008). In the early to
mid-1800s, Americans of European descent moved westward from New England
and began to clear forests and drain wetlands for corn (
Zea mays
L.) and small grains
including oats (
Avena sativa
L.) and wheat (
Triticum aestivum
L.) (Gray 1996). In
the early 1900s, market opportunities expanded for a wide range of horticultural
crops and livestock products. New crops such as alfalfa (
Medicago sativa
L.) and
soybean (
Glycine max
L.) were promoted by the emerging university extension
service, and a diverse suite of crops was grown throughout Michigan (Rudy et al.
2008). A century later, low-diversity row-crop systems supported by agrochemical
