Author(s):
Matthew Stephenson, Matt Woods, Matthew Helmers, Marshall McDaniel, David Sundberg, Michael Thompson, Matt Liebman
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, weather, and planting, harvesting, and pest management activities. An associated data set contains information on corn, soybean, rye, and prairie grain crops and forthcoming datasets contain information on drainage volume and nutrient content and soil moisture and bulk density.
Funder:
Leopold Center for Sustainable Agriculture; Iowa Nutrient Research Center; Agronomy Department, ISU; College of Agriculture and Life Sciences, ISU; ConocoPhillips; USDA NIFA
Award Number:
E2009-18; Center funds; Department funds, College funds; 2007-F-01; IOW05296
Keywords:
COBS, Comparison of Biofuel Cropping Systems, agriculture, agroecosystem, bioenergy, biofuel, biomass, corn, cover crop, native prairie, nutrient management, perennial agriculture, rye, soybean, stover
Project (Abbreviated name):
COBS_experiment_management
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 |
|---|---|---|---|---|
| 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. |
| chemical inputs | active ingredient concentration unit | string | NA | The unit for the accompanying active_ingredient_concentration_value field. |
| chemical inputs | active ingredient concentration value | float | As specified | The numerical concentration of the active ingredient in the applied product. |
| chemical inputs | application date | dateTime | NA | The calendar date of the management action. |
| chemical inputs | application mode | string | NA | The method of applying the chemical to the plot. |
| 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. |
| chemical inputs | application rate of reference chemical value | float | As specified | The numerical application rate given in values and units of a reference chemical instead of the listed active ingredient. |
| chemical inputs | application rate unit active ingredient | string | NA | The unit for the accompanying application_rate_value_active_ingredient field. |
| chemical inputs | application rate value active ingredient | float | As specified | The numerical application rate value of the active ingredient. |
| chemical inputs | application timing | string | NA | Chemical applied before or after crop plants emerge. |
| 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 on the same day, but equipment breakdowns, weather, and time constraints sometimes led to treatments receiving a management activity on different days between blocks. |
| 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 cannot be missing from this field. |
| chemical inputs | chemical purpose | string | NA | The general class of chemical applied. |
| chemical inputs | comment | string | NA | Details that may affect the interpretation of this row of data. |
| chemical inputs | crop | string | NA | The crop, crops, or plant community grown under this treatment. |
| chemical inputs | implement | string | NA | The make and model of the implement used for the application. |
| chemical inputs | original entry | string | NA | The field activity log this entry was derived from. |
| chemical inputs | reference chemical | string | NA | Application rate values were sometimes given in reference to a benchmark reference chemical. |
| 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. |
| chemical inputs | tractor | string | NA | The make and model of the tractor used for the application. |
| chemical inputs | trade name | string | NA | The label under which the chemical was sold. |
| 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. |
| 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 treatment table can be found in the COBS_experiment_management dataset. Values cannot be missing from this field, but they can be duplicated within this table. |
| chemical inputs | treatment long | string | NA | A longer more descriptive treatment name. |
| harvest activities | activity | string | NA | The harvest-related field activity. |
| harvest activities | activity date | dateTime | NA | The calendar date of the management action. |
| 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. |
| harvest activities | comment | string | NA | Details that may affect the interpretation of this row of data. |
| harvest activities | crop | string | NA | The plant and plant part documented in this row. |
| 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. |
| 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 cannot be missing from this field. |
| harvest activities | implement | string | NA | The make and model of the implement used for the field activity. |
| harvest activities | original entry | string | NA | The field activity log entry from which this row was derived. |
| 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. |
| harvest activities | swath units | string | NA | The unit for the accompanying swath_value. |
| harvest activities | swath value | float | As specified | The effective width of the implement. |
| harvest activities | tractor | string | NA | The make and model of the tractor used for the field activity. |
| 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. |
| 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_experiment_management dataset. Values cannot be missing from this field, but they can be duplicated within this table. |
| harvest activities | treatment long | string | NA | A longer more descriptive treatment name. |
| 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 on the same day, but equipment breakdowns, weather, and time constraints sometimes led to treatments receiving a management activity on different days between blocks. |
| planting activities | comment | string | NA | Details that may affect the interpretation of this row of data. |
| planting activities | crop | string | NA | The plant and plant part documented in this row. |
| planting activities | emergence date | dateTime | NA | Date seedlings were visible above the soil, as noted in the field activity logs. |
| planting activities | implement | string | NA | The make and model of the implement used for the field activity. |
| planting activities | maturity unit | string | NA | The unit of the accompanying maturity_value field. |
| planting activities | maturity value | float | As specified | The relative maturation rate. |
| planting activities | original entry | string | NA | The field activity log entry from which this row was derived. |
| 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 cannot be missing from this field. |
| planting activities | planting date | dateTime | NA | The calendar date of the management action. |
| 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. |
| planting activities | seed company | string | NA | The company that produced the seed. |
| planting activities | seed hybrid | string | NA | The strain or variety of the seed. |
| planting activities | seeding rate unit | string | NA | The units for the accompanying seeding_rate_value. |
| planting activities | seeding rate value | float | As specified | The rate at which seeds were planted per unit area. |
| 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. |
| planting activities | tractor | string | NA | The make and model of the tractor used for the field activity. |
| planting activities | trait list | string | NA | A comma separated list of traits associated with the strain or variety. Possibly incomplete. |
| 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. |
| 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_experiment_management dataset. Values cannot be missing from this field, but they can be duplicated within this table. |
| planting activities | treatment long | string | NA | A longer more descriptive treatment name. |
| plot boundaries | block | string | NA | The block within which the treatment was randomized. |
| plot boundaries | geometry | string | NA | A list of vertices as output by the R package 'sf'. Coordinates are in UTM NAD 1983 Zone 15N, EPSG:26915. |
| plot boundaries | plot | string | NA | The name of the plot. The tens digit indicates the block and the numbering for the ones digit goes from one to six within each block. |
| plot boundaries | plot pkey | integer | dimensionless | A unique primary key for this table. |
| 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_experiment_management dataset. Values cannot be missing from this field, but they can be duplicated within this table. |
| 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 cannot be missing from this field. |
| 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. |
| 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_experiment_management dataset. Values cannot be missing from this field, but they can be duplicated within this table. |
| 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. |
| 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. |
| 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 cannot be missing from this field. |
| 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. |
| prairie species planted | comment | string | NA | Comment field provided by Prairie Moon Nursery. No key was provided. |
| prairie species planted | common name | string | NA | The common vernacular name for the prairie plant species as provided by Prairie Moon Nursery. |
| prairie species planted | functional group | string | NA | A broad classification of plant phenotypes. |
| prairie species planted | number of seeds | integer | number | An estimate of the number of seeds provided. |
| prairie species planted | percent by weight | float | percent | Percent by weight in the overall seed mix. |
| prairie species planted | prairie species planted pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| prairie species planted | price dollars | float | USDollar | The price in dollars of the seed. |
| prairie species planted | quantity | float | dimensionless | The weight of the seed in the mix in units specified by 'unit' column. |
| prairie species planted | scientific name | string | NA | The genus and species of the prairie plant species. |
| prairie species planted | unit | string | NA | The unit for the weight specified in the 'quantity' column. |
| treatments | crop | string | NA | The crop, crops, or plant community grown under this treatment. |
| 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. |
| treatments | treatment long | string | NA | A longer more descriptive treatment name. |
| 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 cannot be missing from this field. |
| 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. |
| 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. |
| weather raw | dew point f | float | fahrenheit | The measured dew point averaged over this hour. |
| weather raw | gust direction degrees | float | degree | The measured wind gust direction averaged over this hour. |
| weather raw | precipitation daily in | float | inch | The precipitation summed over all hours in this day. Hourly measurements were not available for the COBS weather station. |
| weather raw | precipitation hourly in | float | inch | The measured precipitation summed over this hour. |
| weather raw | relative humidity percent | float | percent | The measured relative humidity percent averaged over this hour. |
| weather raw | soil temperature 4 in f | float | fahrenheit | The measured soil temperatures at four inch depth averaged over this hour. |
| weather raw | solar radiation watt per sq m | float | wattPerMeterSquared | The measured solar radiation summed over this hour. |
| weather raw | station | string | NA | The station code provided by the Iowa Environmental Mesonet. |
| weather raw | station name | string | NA | A plain language name for the weather station. |
| weather raw | temperature f | float | fahrenheit | The measured air temperatures averaged over this hour. |
| weather raw | timestamp CST CDT | dateTime | NA | The hour over which these weather summaries were measured in Central Standard Time or Central Daylight Time, as appropriate for the date. |
| weather raw | weather pkey | integer | dimensionless | A unique primary key for this table. |
| weather raw | wind direction degrees | float | degree | The measured wind direction averaged over this hour. |
| weather raw | wind gust kn | float | knot | The measured wind gust speed averaged over this hour. |
| weather raw | wind speed kn | float | knot | The measured wind speed averaged over this hour. |