a https://catalog.data.gov/dataset/major‐land‐resource‐areas‐mlra.
Soil Characterization
Soil characterization includes providing a taxonomic description of the typical or most common soil(s) within the experimental site. Inclusion of the taxonomic system is needed for international comparisons. Soil type (e.g., Barnes clay loam), soil texture (sand, silt, and clay contents), typical pH, and bulk density are common soil characteristics, preferably by depth increments. Soil chemistry data include soil C (total, organic, and/or inorganic), soil N (total, NO3, and NH4), and other plant‐essential nutrients (e.g., P and K). Topographic information can be at a broad‐scale site level but can also have much finer granularity related to sampling for response variables. When appropriate, the hillslope position should be noted.
Experimental Descriptors
Experimental descriptors include experimental design (e.g., randomized complete block, split plot), number of replications or plots, study area, plot size, and treatments.
Climate and Weather
Climatic data include long‐term information such as mean annual temperature and mean annual precipitation. It is also useful to include climate characterization descriptors (Kottek, Grieser, Beck, Rudolf, & Rubel, 2006). Finer granularity of climatic data can also be useful, noting if the region experiences freeze–thaw cycles. Weather data might be as simple as noting the location of the nearest weather recording station, while including a link can be especially useful to the modeling community.
Management
Management includes soil, crop, and residue management, cropping related amendments, harvest, and animal management. Within the context of an experiment, management parameters might be considered metadata or treatment data. For example, if the entire study area is managed with a common tillage method or the same cultivar, it would be management metadata. In contrast, if tillage systematically varies across a study based on the selected experimental design, the management is an experimental treatment.
Tillage
When describing tillage, vague terminology like conventional or conservation should be avoided or if used, these terms need to be clearly described by delineating the implement, mode of soil movement (e.g., inversion tillage), depth, tillage frequency, and the date tillage event(s) occur.
Cropping