Approved Site Use Requests (SURFs) — Main Cropping System Experiment (MCSE)

This datatable is part of the Agronomic Practices of the Main Cropping System Experiment dataset.

This dataset includes information on the agronomic practices of the Main Cropping System Experiment (MCSE), including the LTER Main Site treatments (T1-T8) and the Mid-successional (TSF) and Forested (TCF, TDF) sites.

Most long-term hypotheses of the KBS LTER are tested within the context of the MCSE. The LTER Main Site contains 7 different cropping systems (T1-T7) established in 1988 on a 48-ha area divided into 6 replicate blocks (R1-R6) of seven 1-ha plots. Each system is replicated in each block. The eighth system (T8) is a mown grassland on never-tilled soil, located 200 m off-site and replicated in four 0.06 ha plots.

Current MCSE treatments at the LTER Main Site include:

• Conventional (T1): standard chemical input corn/soybean/wheat rotation conventionally tilled (corn/soybean prior to 1992)
• No-till (T2): standard chemical input corn/soybean/wheat rotation no-tilled (corn/soybean prior to 1992)
• Reduced Input (T3): low chemical input corn/soybean/wheat rotation conventionally tilled (ridge till prior to 1994), with a center prairie strip planted in each replicate in 2019
• Biologically Based (T4): zero chemical input corn/soybean wheat rotation conventionally tilled (ridge till prior to 1994), with a center prairie strip planted in each replicate in 2019
• Poplar (T5): Populus clones on short-rotation (6-7 year) harvest cycle
• Switchgrass (T6): planted in 2019 and converted in 2018 from continuous alfalfa, replanted every 6-7 years)
• Early Successional (T7): early successional community on historically tilled soil abandoned in 1989 and burned annually since 1997
• Mown Grassland (Never Tilled; T8); successional community on never-tilled soil, mown annually since 1960

In 1993 three additional successional sites were added to the MCSE to provide reference communities for population and process comparisons. All are within 3 km of and share the same soil series as the LTER Main Site. These include:

• Mid-successional (TSF): three old-field sites on historically tilled cropland abandoned in the 1950s and 1960s
• Coniferous Forest (TCF): three conifer long-rotation plantations established in 1965
• Deciduous Forest: three deciduous forest stands, two old-growth and one logged once ca. 1960

For each treatment (and for some, microplots nested within treatment plots) the following variates are routinely measured (described in greater detail in associated datasets):

• plant characteristics including species distributions and abundances, aboveground net primary production by function;
• soil chemical and physical characteristics, including soil moisture, pH, inorganic N pools, total C and N, and bulk density;
• soil biological characteristics including greenhouse gas fluxes, soil leachate, N mineralization potential (buried bags); and
• insect dynamics including distributions and abundances of major insect pests and predators.