Author(s):
Matt Liebman, Matthew Helmers, Michael Thompson, Marshall McDaniel, Matthew Stephenson, Matt Woods, David Sundberg
Abstract:
The Comparison of Biofuel Cropping Systems (COBS) experiment was designed to compare biomass production, fossil fuel replacement value, and environmental impacts for continuous corn grown for grain and stover removal with (CCW) and without (CC) a rye cover crop; multi-species perennial crops grown for aboveground biomass with (PF) and without (P) fertilizer; and a conventional corn-soybean grain system (C2, S2), used as a comparison baseline. The six treatments were randomly assigned to 27 x 61 m plots in four complete blocks. Plots were designed to be individually-drained by perforated tile lines such that drainage water could be sampled from the center portion of each plot without cross-plot contamination.
This dataset contains information on the management of the experimental site, including spatial layout and planting, harvesting, and pest management activities. Associated data sets contain information on corn, soybean, rye, and prairie grain and biomass yield; drainage volume and nutrient content; root growth; nutrient content of plant and soil material; soil moisture and bulk density; biodiversity; and solar radiation.
Funder:
Leopold Center for Sustainable Agriculture; Iowa Nutrient Research Center; Agronomy Department, ISU; College of Agriculture and Life Sciences, ISU; ConocoPhillips
Keywords:
agriculture, agroecosystem, bioenergy, biofuel, biomass, COBS, Comparison of Biofuel Cropping Systems, corn, cover crop, native prairie, nutrient management, perennial agriculture, rye, soybean, stover
Project (Abbreviated name):
COBS_core
Team:
COBS
Geographic Location:
The Iowa State University Agronomy and Agricultural Engineering South Reynoldson Research Farm located in Boone County, Iowa at the corner of 300th St. and Violet Ave.
Families:
Apiaceae, Apocynaceae, Asteraceae, Commelinaceae, Fabaceae, Lamiaceae, Plantaginaceae, Poaceae
Species:
Amorpha canescens, Andropogon gerardi, Asclepias tuberosa, Astragalus canadensis, Baptisia leucantha, Dalea purpurea, Desmanthus illinoensis, Desmodium canadense, Echinacea pallida, Elymus canadensis, Eryngium yuccifolium, Glycine max, Helianthus maximili
Data Mirror:
Data Table Column Names and Descriptions
| Table Name | Column Name | Data Type | Units | Column Description |
|---|---|---|---|---|
| data.dataset_chemical_inputs | active ingredient | string | NA | The active ingredient in the trade_name product. Products with multiple active ingredients are given as a "+" separated list. |
| data.dataset_chemical_inputs | active ingredient concentration unit | string | NA | The unit for the accompanying active_ingredient_concentration_value field. |
| data.dataset_chemical_inputs | active ingredient concentration value | float | NA | The numerical concentration of the active ingredient in the applied product. |
| data.dataset_chemical_inputs | application date | dateTime | YYYY-MM-DD | The calendar date of the management action. |
| data.dataset_chemical_inputs | application mode | string | NA | The method of applying the chemical to the plot. |
| data.dataset_chemical_inputs | application rate of reference chemical unit | string | NA | The unit of the application rate given in values and units of a reference chemical instead of the listed active ingredient. |
| data.dataset_chemical_inputs | application rate of reference chemical value | float | NA | The numerical application rate given in values and units of a reference chemical instead of the listed active ingredient. |
| data.dataset_chemical_inputs | application rate unit active ingredient | string | NA | The unit for the accompanying application_rate_value_active_ingredient field. |
| data.dataset_chemical_inputs | application rate value active ingredient | float | NA | The numerical application rate value of the active ingredient. |
| data.dataset_chemical_inputs | application timing | string | NA | Chemical applied before or after crop plants emerge. |
| data.dataset_chemical_inputs | blocks | string | NA | A comma separated list of the blocks to which this row pertained. Management actions were planned for all four blocks in the same day, but breakdowns, weather, and time constraints sometimes led to treatments receiving a management activity on different days between blocks. |
| data.dataset_chemical_inputs | chemical input pkey | float | dimensionless | This is the primary key for this table. It is a unique identifier used to match rows in this table with other tables. Foreign keys in other tables will have "_pkey" in this column name replaced by "_fkey". Values can not be missing from this field. |
| data.dataset_chemical_inputs | chemical purpose | string | NA | The general class of chemical applied. |
| data.dataset_chemical_inputs | comment | string | NA | Details that may affect the interpretation of this row of data. |
| data.dataset_chemical_inputs | crop | string | NA | The crop, crops, or plant community grown under this treatment. |
| data.dataset_chemical_inputs | implement | string | NA | The make and model of the implement used for the application. |
| data.dataset_chemical_inputs | original entry | string | NA | The field activity log this entry was derived from. |
| data.dataset_chemical_inputs | reference chemical | string | NA | Application rate values were sometimes given in reference to a benchmark reference chemical. |
| data.dataset_chemical_inputs | study year | float | number | The calendar year for this entry. The overall study began in 2008 and various data were collected in every subsequent year. The study was ongoing at the time of publication. |
| data.dataset_chemical_inputs | tractor | string | NA | The make and model of the tractor used for the application. |
| data.dataset_chemical_inputs | trade name | string | NA | The label under which the chemical was sold. |
| data.dataset_chemical_inputs | treatment | string | NA | This is the official treatment name, which is formatted as an abbreviation of a longer treatment description. This field can be used as a primary/foreign key in most instances. There were six treatments. |
| data.dataset_chemical_inputs | treatment fkey | float | dimensionless | This is a foreign key to link records in the table whose name proceeds "fkey" in the column name. The table can be found in the COBS_core database. Values can not be missing from this field, but they can be duplicated within this table. |
| data.dataset_chemical_inputs | treatment long | string | NA | A longer more descriptive treatment name. |
| data.dataset_harvest_activities | activity | string | NA | The harvest-related field activity. |
| data.dataset_harvest_activities | activity date | dateTime | YYYY-MM-DD | The calendar date of the management action. |
| data.dataset_harvest_activities | blocks | string | NA | A comma separated list of the blocks to which this row pertained. Management actions were planned for all four blocks in the same day, but breakdowns, weather, and time constraints sometimes led to treatments receiving a management activity on different days between blocks. |
| data.dataset_harvest_activities | comment | string | NA | Details that may affect the interpretation of this row of data |
| data.dataset_harvest_activities | crop | string | NA | The plant and plant part documented in this row |
| data.dataset_harvest_activities | cutting height inches | float | inch | The height of the stubble remaining after mowing. In cases where a range was given, the midpoint is recorded here. |
| data.dataset_harvest_activities | harvest activity pkey | float | dimensionless | This is the primary key for this table. It is a unique identifier used to match rows in this table with other tables. Foreign keys in other tables will have "_pkey" in this column name replaced by "_fkey". Values can not be missing from this field. |
| data.dataset_harvest_activities | implement | string | NA | The make and model of the implement used for the field activity |
| data.dataset_harvest_activities | original entry | string | NA | The field activity log this entry was derived from |
| data.dataset_harvest_activities | study year | float | number | The calendar year for this entry. The overall study began in 2008 and various data were collected in every subsequent year. The study was ongoing at the time of publication. |
| data.dataset_harvest_activities | swath units | string | NA | The unit for the accompanying swath_value |
| data.dataset_harvest_activities | swath value | float | NA | The effective width of the implement |
| data.dataset_harvest_activities | tractor | string | NA | The make and model of the tractor used for the field activity |
| data.dataset_harvest_activities | treatment | string | NA | This is the official treatment name, which is formatted as an abbreviation of a longer treatment description. This field can be used as a primary/foreign key in most instances. There were six treatments. |
| data.dataset_harvest_activities | treatment fkey | float | dimensionless | This is a foreign key to link records in the table whose name proceeds "fkey" in the column name. The table can be found in the COBS_core database. Values can not be missing from this field, but they can be duplicated within this table. |
| data.dataset_harvest_activities | treatment long | string | NA | A longer more descriptive treatment name. |
| data.dataset_planting_activities | blocks | string | NA | A comma separated list of the blocks to which this row pertained. Management actions were planned for all four blocks in the same day, but breakdowns, weather, and time constraints sometimes led to treatments receiving a management activity on different days between blocks. |
| data.dataset_planting_activities | comment | string | NA | Details that may affect the interpretation of this row of data. |
| data.dataset_planting_activities | crop | string | NA | The plant and plant part documented in this row. |
| data.dataset_planting_activities | emergence date | dateTime | YYYY-MM-DD | Date seedlings were visible above the soil, as noted in the field activity logs. |
| data.dataset_planting_activities | implement | string | NA | The make and model of the implement used for the field activity. |
| data.dataset_planting_activities | maturity unit | string | NA | The unit of the accompanying maturity_value field. |
| data.dataset_planting_activities | maturity value | float | NA | The relative maturation rate. |
| data.dataset_planting_activities | original entry | string | NA | The field activity log this entry was derived from. |
| data.dataset_planting_activities | planting activity pkey | float | dimensionless | This is the primary key for this table. It is a unique identifier used to match rows in this table with other tables. Foreign keys in other tables will have "_pkey" in this column name replaced by "_fkey". Values can not be missing from this field. |
| data.dataset_planting_activities | planting date | dateTime | YYYY-MM-DD | The calendar date of the management action. |
| data.dataset_planting_activities | planting depth inch | float | inch | The depth the seeds were planted. Target depth was 1.5-2.5 inches for both corn and soybeans across all years. |
| data.dataset_planting_activities | seed company | string | NA | The company that produced the seed. |
| data.dataset_planting_activities | seed hybrid | string | NA | The strain or variety of the seed. |
| data.dataset_planting_activities | seeding rate unit | string | NA | The units for the accompanying seeding_rate_value. |
| data.dataset_planting_activities | seeding rate value | float | NA | The rate at which seeds were planted per unit area. |
| data.dataset_planting_activities | study year | float | number | The calendar year for this entry. The overall study began in 2008 and various data were collected in every subsequent year. The study was ongoing at the time of publication. |
| data.dataset_planting_activities | tractor | string | NA | The make and model of the tractor used for the field activity. |
| data.dataset_planting_activities | trait list | string | NA | A comma separated list of traits associated with the strain or variety. Possibly incomplete. |
| data.dataset_planting_activities | treatment | string | NA | This is the official treatment name, which is formatted as an abbreviation of a longer treatment description. This field can be used as a primary/foreign key in most instances. There were six treatments. |
| data.dataset_planting_activities | treatment fkey | float | dimensionless | This is a foreign key to link records in the table whose name proceeds "fkey" in the column name. The table can be found in the COBS_core database. Values can not be missing from this field, but they can be duplicated within this table. |
| data.dataset_planting_activities | treatment long | string | NA | A longer more descriptive treatment name. |
| data.plot_treatment_years | plot fkey | float | dimensionless | This is a foreign key to link records in the table whose name proceeds "fkey" in the column name. That table can be found in the COBS_core database. Values can not be missing from this field, but they can be duplicated within this table. |
| data.plot_treatment_years | plot treatment year pkey | float | dimensionless | This is the primary key for this table. It is a unique identifier used to match rows in this table with other tables. Foreign keys in other tables will have "_pkey" in the column name replaced by "_fkey". Values can not be missing from this field. |
| data.plot_treatment_years | study year | float | number | The calendar year for this entry. The overall study began in 2008 and various data were collected in every subsequent year. The study was ongoing at the time of publication. |
| data.plot_treatment_years | treatment fkey | float | dimensionless | This is a foreign key to link records in the table whose name proceeds "fkey" in the column name. The table can be found in the COBS_core database. Values can not be missing from this field, but they can be duplicated within this table. |
| data.plots | block | float | dimensionless | This is the block within which treatments were replicated. Numbering begins at one for the North-east site quadrant and continues two through four clockwise around the site. Blocks were separated by mowed grass alleyways. |
| data.plots | plot | float | dimensionless | This is the official plot designation. It takes the form of a two-digit number comprised of the block number and a sequential integer counting up from one starting at the eastern-most plot within the block and increasing to the west. It can be used as a primary or foreign key in most instances. |
| data.plots | plot pkey | float | dimensionless | This is the primary key for this table. It is a unique identifier used to match rows in this table with other tables. Foreign keys in other tables will have "_pkey" in this column name replaced by "_fkey". Values can not be missing from this field. |
| data.plots | site quadrant | string | NA | The spatial arrangement of the blocks relative to one another. Blocks were oriented north to south and east to west. Plots were directly adjacent within blocks and blocks had mowed grass alleyways between them. |
| data.treatments | crop | string | NA | The crop, crops, or plant community grown under this treatment. |
| data.treatments | treatment | string | NA | This is the official treatment name, which is formatted as an abbreviation of a longer treatment description. This field can be used as a primary/foreign key in most instances. There were six treatments. |
| data.treatments | treatment long | string | NA | A longer more descriptive treatment name. |
| data.treatments | treatment pkey | float | dimensionless | This is the primary key for this table. It is a unique identifier used to match rows in this table with other tables. Foreign keys in other tables will have "_pkey" in this column name replaced by "_fkey". Values can not be missing from this field. |
| data.treatments | treatment year plus one | string | NA | The treatment that this treatment cycles to in the next crop year. Only C2 and S2 change between years and they alternate. |
| data.treatments | treatment year plus two | string | NA | The treatment cycle that this treatment will be in the year after next. Only C2 and S2 change between years and they alternate. |