MassGIS Data: Land Use Summary Statistics

September 2003, August 2007

- Set 1: 21 Categories by town; development; LU change   (Zip file containing 10 dBase tables and 1 Microsoft Excel file with multiple worksheets; 1.2 MB)  - Set 2: Grouped categories, acreage and change by Town and County   (Zip file containing 1 statewide, 14 county and 351 town Microsoft Excel files; 1.6 MB)

Set 1 (September 2003)
The Land Use Summary Statistics tables aggregate land use areas on a town-by-town basis for the commonwealth of Massachusetts. The statistics were generated from the polygon attribute table from MassGIS' Land Use Datalayer for the years for which land use data have been collected statewide, 1971, 1985, and 1999. The 21-class MacConnell land use categories were used as the basis of the tables, which summarize acreage of each land use type, "developed" vs. "undeveloped" land, and change from 1971 to 1985 and 1985 to 1999.

Set 2 (August 2007)
This second set of Land Use Summary Statistics aggregates the 21-class land use into six categories -- Agriculture, Forest, Open Land, Recreation, Urban, and Water. For each category, some of which are further subdivided, there are acreage totals for 1971, 1985, and 1999, as well as acreage and percent change from '71 to '85 and '85 to '99. Totals are available for the entire state, for each of the 14 counties, and for each of the 351 municipalities. Processing was done by the state Department of Conservation and Recreation, Management Forestry Program , based on the Land Use Datalayer polygon attribute table.

Production (Set 1)

The land use data is stored at MassGIS in an Oracle-based ArcSDE format. A series of Oracle SQL*Plus queries were conducted by MassGIS staff, with the results copied into a Microsoft Excel spreadsheet. An example of a query is as follows:

SET  PAGESIZE 400
SELECT DISTINCT *
FROM (
    SELECT  C.town                     "TOWN",
            A.lu21_1999                "LU_CODE",
            NVL (A.sum_area_acres, 0)  "ACRES"
    FROM      (
              SELECT    tile_name,
                        lu21_1999,
                        SUM (area_acres) sum_area_acres
              FROM      gisdata.landuse_poly
              WHERE     lu21_1999 = 21
              GROUP BY  tile_name,
                        lu21_1999
              ) A,
              gisdata.towns_poly C
      WHERE   A.TILE_NAME (+) = C.town_id
      ORDER BY C.TOWN
      );

In this particular query, areas in acres are being generated for each town, showing how many acres were dedicated to land use type "Woody Perennial" (code = 21) in 1999.

All combinations of years and land use types were produced from the queries, with the results stored in an Excel spreadsheet. Changes in land use areas were also calculated, using the data derived from the queries and formulas referencing them in the same spreadsheet. Finally, two common aggregations of land use areas were also generated -- one spreadsheet that shows the area of developed vs. undeveloped land uses for all years of interest, and three other spreadsheets that show the areas of land use as aggregated by the land use-zoning crosswalk translation codes, one for each year of interest.

When all numbers were calculated, stand-alone Excel worksheets were created from the spreadsheet, an Access database was created from comprehensive imports of the worksheets, and individual dBase tables were generated. The dBase tables were then imported into ArcSDE.

The resulting tables are as follows: 

Table Name	Contents
LANDUSE_STATS_71	1971 area sums in acres for all landuse types for each municipality
LANDUSE_STATS_85	1985 area sums in acres for all landuse types for each municipality
LANDUSE_STATS_99	1999 area sums in acres for all landuse types for each municipality
LANDUSE_STATS_7185	Changes in acreage for each landuse type for each municipality between 1971 and 1985
LANDUSE_STATS_7199	Changes in acreage for each landuse type for each municipality between 1971 and 1999
LANDUSE_STATS_8599	Changes in acreage for each landuse type for each municipality between 1985 and 1999
LANDUSE_STATS_DEV	Area sums in acres for each municipality for all years of interest differentiating between "developed" and "undeveloped" landuse
LANDUSE_STATS_Z71	1971 area sums in acres for each municipality, aggregating landuse types by the landuse-zoning crosswalk code used for the buildout projects
LANDUSE_STATS_Z85	1985 area sums in acres for each municipality, aggregating landuse types by the landuse-zoning crosswalk code used for the buildout projects
LANDUSE_STATS_Z99	1999 area sums in acres for each municipality, aggregating landuse types by the landuse-zoning crosswalk code used for the buildout projects

Land Use Codes

Codes in the MacConnell land use classification scheme used in the tables (21 categories, based on the "LU21_<year>" items): 

Code	Land Use
1	Crop Land
2	Pasture
3	Forest
4	Non-forested Wetlands
5	Mining
6	Open Land
7	Participation Recreation
8	Spectator Recreation
9	Water-based Recreation
10	Multi-family Residential
11	High Density Residential
12	Medium Density Residential
13	Low Density Residential
14	Salt Water Wetlands
15	Commercial
16	Industrial
17	Urban Open
18	Transportation
19	Waste Disposal
20	Water
21	Woody Perennial

"Developed" vs. "Undeveloped"

The "Developed" vs. "Undeveloped" aggregations were based on the following MacConnell land use codes:
Developed Land = MacConnell codes 7,8,9,10,11,12,13,15,16,17,18,19
Undeveloped Land = MacConnell codes 1,2,3,4,5,6,14,20,21

Land Use/Zoning Crosswalk

The three land use/zoning tables attempt to match zoning codes with MacConnell land use codes to predict future land use. This method was incorporated into the EOEA Buildout Analyses, primarily for display purposes to depict land use at buildout. The Land Use-Zoning (LUZ) Crosswalk Aggregations are as follows:

LUZ Code	LUZ Category	Land Use Code(s)
A	Agriculture	1,2,21
O	Open Undeveloped Land	6
C	Commercial	15
I	Industrial/Transportation/Mining	5,16,18,19
HDR	Higher Density Residential	10,11
MDR	Medium Density Residential	12
LDR	Low Density Residential	13
VLDR	Very Low Density Residential	does not exist in landuse, solely for zoning purposes
U	Urban Open/Institutional/Recreation	7,8,9,17
N	Natural Land/Undisturbed Vegetation	3,4,14
W	Water	20

Also see the Crosswalk graphic  (PDF, 8 KB).

Attributes (Set 1)

Table field names use the MacConnell land use and LUZ codes and 2-digit year (e.g., 71, 85, 99). Town IDs are based  on those used in the Towns layer TOWN_ID field.

Maintenance

MassGIS is maintaining the Set 1 tables. DCR maintains Set 2.

Last Updated 8/17/2007