NITROGEN FERTILIZER SALES FOR 1990

ABSTRACT:

This coverage contains estimates of nitrogen-fertilizer sales for the conterminous United States in 1990 as reported by the U.S. Environmental Protection Agency (1990) and by Jerald Fletcher (West Virginia University, written commun., 1992). Nitrogen-fertilizer sales estimates in this coverage are reported for each county polygon in tons of actual nutrient sold (inorganic nitrogen, phosphate, and potash) as distinct from total tons of fertilizer product.                                                
                                                                                
The data are summarized for fertilizer years (i.e. the 1987 fertilizer year runs from July 1, 1986 to June 30, 1987).                             

This coverage shows total tons and tons per square mile of fertilizer sales by county.  It is useful for comparing nitrogen fertilizer sales between different counties.  The presumption underlying the use of this data is that sales occurring within a county are related to fertilizer use in that county.  

A copy of the full US coverage is provided for comparison purposes (as Nit90US.shp).  However, the full US coverage remains in its original (Albers) projection, and has not been rectified to the UTM projection used in WATER.  

A subset of Nit90 data for the five WATER counties has been applied to a UTM-rectified county coverage, allowing it to be overlaid with other WATER coverages.

LINEAGE INFORMATION:

This data set was obtained from the EPA Web site on 3/31/97.  The original file was in a GZipped .e00 file format in Albers projection, and covered the entire U.S.  The file was unzipped and converted using the ArcView Import71 program.  An attempt was made to re-project and clip the NIT90 theme using TNT MIPS and ArcView, however, projection problems could not be resolved.  Instead, the attribute data was transferred to a shapefile of county boundaries previously developed using Census TIGER line files.  This allowed the data to be provided in a form consistent with other data layers on the WATER CD.

The following is extracted from the metadata documentation provided at EPA's Web site and found in the document Nit90.doc in the Nit90 directory on this CD:

NITROGEN-FERTILIZER SALES ATTRIBUTES                                       
                                                                                
        Nitrogen-fertilizer sales estimate were generated and are reported as   
      tons of actual nutrient. The data are summarized for fertilizer years     
      (i.e. the 1987 fertilizer year runs from July 1, 1986 to June 30, 1987).  
                                                                                
        Nitrogen-fertilizer sales estimates by county were constructed from     
      estimates reported by the U.S. Environmental Protection Agency (1990) for 
      1985-89 and by Jerald Fletcher (West Virginia University, written commun.,
      1992) for 1990-91. The estimates are provided for seven years (1985-91)   
      in seven ARC/INFO coverages (NIT85, NIT86, NIT87, NIT88, NIT89, NIT90,    
      and NIT91); however, the 1987 Census of Agriculture data on fertilizer    
      expenditures used to disaggregate State sales totals to county-level      
      sales estimates represents only 1987 sales.                               
                                                                                
        Eleven attributes were added to an ARC/INFO coverage for each year      
      of fertilizer-sales data. All attribute names contain a number that       
      represents the year of the data. For example, NTOT86 is the attribute     
      name for total nitrogen-fertilizer sales in 1986. Sales estimates are     
      provided for total nitrogen, potash, and phosphate, and for nitrogen      
      sold as ammonium nitrate, anhydrous ammonia, miscellaneous forms,         
      nitrogen solutions, and urea. Example nitrogen-fertilizer sales coverage  
      names, attribute names, and short attribute definitions are listed in     
      table 1.                                                                  
                                                                                
                                                                                
      Table 1. Nitrogen-fertilizer sales, 1990 coverage name, attribute names,  
      and short attribute descriptions                                          
      
                                                                                
NIT90--Coverage of nitrogen-fertilizer sales estimates, 1990 

Attribute name	Description 

NTOT90	Total estimated nitrogen-fertilizer sales, 1990 (tons) 
NTOT90_USE	Rate of nitrogen-fertilizer use in county polygon (tons per square mile)
K2090	Estimated potash sales, 1990 (tons) 
K2090_USE	Rate of potash use in county polygon (tons per square mile
P20590	Estimated phosphate sales, 1990 (tons)
P20590.USE	Rate of phosphate use in county polygon (tons per square mile)
AMNI90	Fertilizer sold as ammonium nitrate, 1990 (tons)
ANHY90	Fertilizer sold as anhydrous ammonia, 1990 (tons)
NMIS90	Fertilizer sold as miscellaneous forms in tons, 1990
NSOL90	Fertilizer sold as nitrogen solutions in tons, 1990
UREA90	Fertilizer sold as urea in tons, 1990