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GIS Shapefile - Vegetation for private lands, Baltimore City

Vegetation (trees and grass) for parcels defined as private land within Baltimore City. Private land parcels consisted of all those parcels with land use (LU) codes except for the category "Exempt Commercial" (EC). Roads had no LU codes. No parcels with the following LU codes were present in Baltimore City: agricultural (A), county club (CA), marsh land (MA), non-perc land (NP), and town house (TH). LU codes were determined from the Maryland Property View 2003 A&T database. A cursory analysis of the parcel data indicated that errors of omission were present due to insufficient parcel data in certain block groups. Vegetation data used in this analysis came from the MD DNR Forest Service IKONOS derived Strategic Urban Forest Assessment (SUFA) vegetation layer.

GIS Shapefile - Vegetation for private lands, block group, Baltimore City

Block group summary of private land vegetation (forest and grass). The private land area consists of all parcels not classified as "Exempt Commerical." A cursory analysis of the parcel data indicated that errors of omission were present due to insufficient parcel data in certain block groups. Vegetation data used in this analysis came from the MD DNR Forest Service IKONOS derived Strategic Urban Forest Assessment (SUFA) vegetation layer. The amount of private land forest, grass, and total vegetation was summarized on a block group level. In addition the normalized private land forest, grass, and total vegetation was summarized at block group level by dividing by the area of private land.

GIS Shapefile - Riparian vegetation (forest and grass only) within a 100ft buffer of all 1:24K streams in Baltimore City.

Riparian vegetation (forest and grass only) within a 100ft buffer of all 1:24K streams in Baltimore City. Vegetation data used in this analysis came from the MD DNR Forest Service IKONOS-derived Strategic Urban Forest Assessment (SUFA) vegetation layer.

GIS Shapefile - Riparian vegetation (forest and grass only) within a 100ft buffer of all 1:24K streams in Baltimore City, block group

Block group summary of riparian vegetation (forest and grass only) within a 100ft buffer of all 1:24K streams in Baltimore City for only those block groups that intersect the stream buffers. The riparian area consists of all land within a 100 ft buffer of 1:24K streams. Vegetation data used in this analysis came from the MD DNR Forest Service IKONOS-derived Strategic Urban Forest Assessment (SUFA) vegetation layer.

GIS Shapefile - Urparian (non-parcel) vegetation (forest and grass) in Baltimore City

Urparian (non-parcel) vegetation (forest and grass) in Baltimore City. The urparian area consists of all roads and rights of way along roads. This area was delineated using Baltimore City parcel data by identifying all "non-parcel" areas. A cursory analysis of the "non-parcel" areas indicated that errors of omission were present due to insufficient parcel data. Vegetation data used in this analysis came from the MD DNR Forest Service IKONOS derived Strategic Urban Forest Assessment (SUFA) vegetation layer.

GIS Shapefile - Urparian (non-parcel) vegetation (forest and grass) in Baltimore City, block group

Block group summary of urparian (non-parcel) vegetation (forest and grass). The urparian area consists of all roads and rights of way along roads. This area was delineated using Baltimore City parcel data by identifying all "non-parcel" areas. A cursory analysis of the "non-parcel" areas indicated that errors of omission were present due to insufficient parcel data. Vegetation data used in this analysis came from the MD DNR Forest Service IKONOS derived Strategic Urban Forest Assessment (SUFA) vegetation layer.

Plant survey of current vegetation, central Arizona Phoenix: desert vegetation site locations.

An extensive survey was conducted to assess the species diversity of natural desert vegetation around the CAP-LTER study area. Remnant patch habitats (mostly parks and preserves) occurring within the urban matrix / fringe were emphasized. Three outlying areas (White Tank mountains west of town, Union Hills north of town, and Usery Mountain Park east of town) were surveyed for comparison. The original intent was to provide data on the woody and spring / summer herbaceous species in each area, but drought conditions allowed the spring herbs to be surveyed twice (1998, 2001) and summer herbs surveyed only once (1999). Thus, all locations have woody data but only a subset has herbaceous data. Surveys consisted of transects (elaborated below) summarized by the patch or outlying area name followed by a number (e.g. Unhill-11, Squaw-40, Hayden-8). Herb datasets are signified by a Â‘PÂ’ for spring and a Â‘UÂ’ for summer following the transect number (e.g. PaPk-1P, PaPk-1U).

Modified Soil Adjusted Vegetation Index, (M)SAVI image of 2003 ASTER image

Modified Soil-Adjusted vegetation index (MSAVI) produced from the 2003 ASTER image. MSAVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation. It is specifically designed for areas with low vegetation, such as arid lands, where soil reflectance in the signal is high. The index is intended to minimize the effect of bare soil.

Normalized Difference Vegetation Index (NVDI) image of 2000 Landsat Enhanced Thematic Mapper image

Normalized difference vegetation index (NDVI) produced from the 2000 Enhanced Landsat Thematic Mapper(ETM) image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation. It is computed as follows: (NIR-RED) / (NIR+RED), where NIR (Near Infra-Red) is the ETM band 4 (0.76-0.9 micrometers) and RED is band 3 (0.78-0.82 micrometers).

Soil Adjusted Vegetation Index (SAVI) image of 2000 Landsat Enhanced Thematic Mapper (ETM) image

Soil Adjusted Vegetation Index (SAVI) produced from the 2000 Enhanced Landsat Thematic Mapper(ETM) image. SAVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation. It is computed as follows:( (NIR-RED) / (NIR+RED+L))*(1+L), where NIR (Near Infra-Red) is the ETM band 4 (0.76-0.9 micrometers), RED is band 3 (0.78-0.82 micrometers), and L is the correction factor whose values range from 0 (high vegetation cover) to 1 (low vegetation). L=0.5 was used. The index has been designed to correct for high soil reflectance in arid regions.

NDVI (Normalized difference vegetation index) Image of 1975 Landsat MSS Image

Normalized difference vegetation index (NDVI) produced from the 1975 Landsat MSS image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.

SAVI (Soil Adjusted Vegetation Index) Image of 1975 Landsat MSS Image

SAVI (Soil Adjusted Vegetation Index) map produced from the 1975 Landsat MSS image. SAVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.

NDVI (Normalized difference vegetation index) Image of 1980 Landsat MSS Image

Normalized difference vegetation index (NDVI) produced from the 1980 Landsat MSS image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.

SAVI (Soil Adjusted Vegetation Index) Image of 1980 Landsat MSS Image

SAVI (Soil Adjusted Vegetation Index) map produced from the 1980 Landsat MSS image. SAVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.

SAVI (Soil Adjusted Vegetation Index) image of central Arizona-Phoenix from a 2005 Landsat Thematic Mapper image

Soil Adjusted Vegetation Index (SAVI) produced from the 2005 Landsat Thematic Mapper(ETM) image. SAVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation. It is computed as follows:( (NIR-RED) / (NIR+RED+L))*(1+L), where NIR (Near Infra-Red) is the TM band 4 (0.76-0.9 micrometers), RED is band 3 (0.78-0.82 micrometers), and L is the correction factor whose values range from 0 (high vegetation cover) to 1 (low vegetation). L=0.5 was used. The index has been designed to correct for high soil reflectance in arid regions.

NDVI (Normalized difference vegetation index) image of central Arizona-Phoenix from a 2005 Landsat Thematic Mapper image

Normalized difference vegetation index (NDVI) produced from the 2005 Landsat Thematic Mapper (TM) image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation. It is computed as follows: (NIR-RED) / (NIR+RED), where NIR (Near Infra-Red) is the TM band 4 (0.76-0.9 micrometers) and RED is band 3 (0.78-0.82 micrometers).

Spectrally unmixed percent of impervious surface, soil, and vegetation cover in central Arizona-Phoenix, year 2000

Urban land covers (e.g., cement parking lots, asphalt roads, shingle rooftops, grass, tress, exposed soil) can only be recorded as either present or absent in each pixel when using traditional per-pixel classifiers. Sub-pixel analysis approaches that can provide the relative fraction of surface covers within a pixel may be a potential solution to effectively identifying urban impervious areas. Spectral mixture analysis approach is probably the most commonly used approach that models image spectra as spatial average of spectral signatures from two or more surface features. However, spectral mixture analysis does not account for the absence of one of the surface features or spectral variation within pure materials since it utilizes an invariable set of surface features. Multiple endmember spectral mixture analysis (MESMA) approach addresses these issues by allowing endmembers to vary on a per pixel basis. The MESMA technique was employed in this study to model Landsat ETM+ reflectance in the Phoenix metropolitan area. Field spectra of vegetation, soil, and impervious surface areas collected with the use of a fine resolution Quickbird image and pixel purity index tool in ENVI software were modeled as reference endmembers in addition to photometric shade that was incorporated in every model. This study employs thirty endmembers and six hundred and sixty spectral models to identify soil, impervious, vegetation, and shade in the Phoenix metropolitan area. The mean RMS error for the selected land use land cover classes range from 0.003 to 0.018. The Pearson correlation between the fraction outputs from MESMA and reference data from Quickbird 60 cm resolution data for soil, impervious, and vegetation were 0.7052, 0.7249, and 0.8184 respectively.

NDVI (Normalized difference vegetation index) image of central Arizona-Phoenix from a 1998 Landsat Thematic Mapper image

Normalized difference vegetation index (NDVI) produced from the 1998 Landsat Thematic Mapper(TM) image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.

NDVI (Normalized difference vegetation index) image of central Arizona-Phoenix from a 1993 Landsat Thematic Mapper image

Normalized difference vegetation index (NDVI) produced from the 1993 Landsat Thematic Mapper(TM) image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.

NDVI (Normalized difference vegetation index) image of central Arizona-Phoenix from a 1985 Landsat Thematic Mapper image

Normalized difference vegetation index (NDVI) produced from the 1985 Landsat Thematic Mapper(TM) image. NDVI is a means of monitoring density and vigour of green vegetation growth using the spectral reflectivity of solar radiation.