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Dataset Abstract This dataset includes information about the LTER main site treatments, agronomic practices carried out on the treatments and approved site use requests. Most long-term hypotheses associated with the KBS LTER site are being tested within the context of the main cropping systems study. This study was established on a 48 ha area on which a series of 7 different cropping systems were established in spring 1988, each replicated in one of 6 ha blocks. An eighth never-tilled successional treatment, is located 200 m off-site, replicated as four 0.06 ha plots. Cropping systems include the following treatments: T1. Conventional: standard chemical input corn/soybean/wheat rotation conventionally tilled (corn/soybean prior to 1992) T2. No-till: standard chemical input corn/soybean/wheat rotation no-tilled (corn/soybean prior to 1992) T3. Reduced input: low chemical input corn/soybean/wheat rotation conventionally tilled (ridge till prior to 1994) T4. Biologically based: zero chemical input corn/soybean wheat rotation conventionally tilled (ridge till prior to 1994) T5. Poplar: Populus clones on short-rotation (6-7 year) harvest cycle T6. Alfalfa: continuous alfalfa, replanted every 6-7 years (converted to switchgrass in 2018) T7. Early successional community: historically tilled soil T8. Mown grassland community: never-tilled soil. For specific crops in a given year see the Annual Crops Summary Table. In 1993 a series of forest sites were added to the main cropping system study to provide long-term reference points and to allow hypotheses related to substrate diversity to be tested. These include: TCF. Coniferous forest: three conifer plantations, 40-60 years old TDF. Decidious forest: three deciduous forest stands, two old-growth and one 40-60 years post-cutting TSF. Mid-successional forest: three old-field (mid-successional) sites 40+ years post-abandonment. All share a soil series with the main cropping system treatments, and are within 5 km of all other sites. For each system (and for a number of microplot treatments nested within the main treatment plots) the following baseline variates are being measured (described in greater detail in other data set descriptors): plant characteristics, including species distributions and abundances, net aboveground productivity by functional group (crop vs. non dominant biomass, selected non dominant biomass), economic yields, tissue C and N contents, seed bank composition; soil chemical and physical characteristics, including soil moisture, pH, inorganic N and P pools, total C, N, and P pools, bulk density; soil biological characteristics, including microbial biomass C and N, N mineralization rates (buried bags), microbial populations, invertebrate populations; and insect and pathogen dynamics, including distributions and abundances of major insect pests and predators and of Fusarium pathogens. original data source http://lter.kbs.msu.edu/datasets/7
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This content will become publicly available on March 18, 2026
Ecologically Driven Alteration of Soil Hydraulic Properties through mono-culture Reforestation in Central Chile
Soil hydraulic properties (SHP) are among the indicators of the diversity and health of an ecosystem and are commonly measured by two criteria: infiltration and water retention capacity. This may be seen as an “Ecological Alteration,” resulting from the sum biological and nonbiological processes which modify the structure of the soil, including bioturbation and the accumulation of organic matter. These changes in soil structure drive the changes in SHP. Central Chile has seen an abrupt and extensive land use/land cover transition from several hundred years of wheat cultivation (annually tilled) to short rotation (~25-30 yr) silviculture. This allows for neighboring assessment of soil impacts of transitioning from cultivated to uncultivated production as a function of time. Further, the region’s climate geography (a NorthSouth primary axis) allows us to view the soil health impacts of this change in planting along a precipitation gradient (850 – 1700 mm/yr) to help tease-out the impact of climate on temporal dynamics of soil properties. We measured infiltration in five recently transitioned first rotation locations along this precipitation gradient. Sampling plots were established for continuous wheat, early-, mid-, and late-stage pine plantations, and Chilean Native Forest. We sampled in both the dry summer months and again in the wet winter months. In the dry sampling period, we found transitions from wheat to silviculture saw an initial decrease in infiltration; however, over time (~30 years) infiltration in the plantations approached that of the Native Forest (increasing approximately by an order of magnitude in 30 years). In the wet sampling period, the results were more inconclusive. Some plots did not show an increase in infiltration capacity while others showed a gradual increase over the same 30-year period.
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- Award ID(s):
- 2243964
- PAR ID:
- 10588866
- Publisher / Repository:
- EGU
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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