GIS Site Suitability Analysis for developing a

vineyard in Sonoma County, CA

____________________________

David JaquetRaster GIS & Modeling (32-

630-01)Fall 2005

Motivation

• Sonoma County is one of the two best producing wine regions of the north central coast of California.

• I am interested in visualizing the criteria matrix needed for correctly choosing a potential land development for a vineyard, I may want to develop a vineyard in the future.

Study Area

Sonoma County, CA wine regions (Appellations)

Research Objectives

• This GIS suitability model analyzes potential suitable land for creating a vineyard in Sonoma County, CA.

• The model has both descriptive and prescriptive components as it describes various suitability criteria themes within Sonoma County and uses these criteria themes in a matrix to prescribe where a vineyard should be developed to be successful.

Methodology The physiographic criteria were chosen from a variety of web sources. These

criteria can determine optimal land parcel characteristics for developing a successful vineyard.

Dataset Primary Derived Criteria Primary Raster Analysis Parameters

Regional 30m 7.5' x 7.5' DEM 1:24,000 dataset

Sonoma County Slope 5% ≤ Slope ≤ 35%; reclass 1 category

Sonoma County Aspect 112° ≤ Aspect ≤ 337°; reclass 1 category

Sonoma County Elevation 0 m ≤ Elevation ≤ 800 m; reclass 1 category

California Counties dataset Sonoma county Select Sonoma Co., make new layer

California Land use dataset Sonoma County agriculture land Select all agriculture land in Sonoma County

California Hydrography dataset Sonoma County hydro features Select hydro features in Sonoma County; reclass 1 category

Distance buffer from hydro source Raster Dist. buffer 0-100 m bad fit, 100+ m good fit; reclass with 2 categories

Sonoma County soils dataset Soil constituents suitable for vineyards in Sonoma County

Chemicals/organic constituents suitable for vineyards in Sonoma County

Existing vineyards survey (1997) Vineyards surveyed in 1997 in Sonoma County

Feature to raster; reclass to 1 category.

Flowchart 1

Re-project To Geographic Coordinate SystemSpatial Reference: NAD_1983_UTM_Zone_10NDatum: D_North_American_1983

Re-project to Geographic Coordinate System:Spatial Reference: NAD_1983_UTM_Zone_10NDatum: D_North_American_1983

Vector Lattices (d38123, d38122)Define Geographic Coordinate System:Spatial Reference: NAD_1983_UTM_Zone_10NDatum: D_North_American_1983

Raster Grids (d38123, d38122)Define Geographic Coordinate System:Spatial Reference: NAD_1983_UTM_Zone_10NDatum: D_North_American_1983

Re-project To Geographic Coordinate SystemSpatial Reference: NAD_1983_UTM_Zone_10NDatum: D_North_American_1983

Select/Query/make new layer

Sonoma county

Raster to feature

CA Landusefeatures

Select/Query/make new layer of Land use features within Sonoma County feature layer

Sonoma CoLand use Features

Continue to flowchart 2

Mosaic rasters d38123 and d38122 to a new combined DEM

Overlay

Regional DEM

Sonoma County DEM

Continue to flowchart 2

For elevation

Continue to flowchart 2For Slope

Continue to flowchart 2For Aspect

CA Hydro features(Lakes)

Sonoma Countyfeature

Sonoma Countyraster

Sonoma Co stream features

Continue to flowchart 2

Feature to raster

CA Landuse (mgmtscape_vt) dataset (raster)

Regional 30m 7.5' x 7.5' DEM 1:24,000

dataset

California counties (feature)

CA Hydrography-rivers/sreams

(features)

Re-projectedDataset

Re-projectedDataset

Re-projectedDataset

Re-projectedDataset

Select/querystreams within Sonoma Co.

CA Hydrography- lakes (features)

Re-project to Geographic Coordinate System:Spatial Reference: NAD_1983_UTM_Zone_10NDatum: D_North_American_1983

Re-projectedDataset

CA Hydro features(Lakes)

Select/querylakes within Sonoma Co.

Sonoma Co Lakes features

Continue to flowchart 2

Flowchart 2

0-100 m

Calculate Slope Grid (Raster)

Slope Grid

Calculate 5≤[slope]≤35

Sonoma Co DEM Sonoma Co DEM

Calculate Aspect Grid

DEM

Aspect Grid

Aspect Grid“Good Aspect”

“Good Topo”Grid

Land suitable for developing a successful vineyard !

(Raster)

Feature to raster

StreamGrid

Reclass grid 1 cat

Sonoma Co stream

features

StreamGrid

Create Buffer: Max distance 1000m

Reclass Buffer distance 2 categories

100-1000m

Hydro bufferedGrid

Slope Grid“Good Slope”

Sonoma Co DEM

Calculate elevatin

0≤[DEM]≤800

Elevation Grid“Good Elevation”

Sonoma Co Landuse features

Select/Query Agriculture

landuse

Sonoma CoAgriculture land

features

Feature to raster

Hydro bufferedGrid – 2 categories0-100m ‘bad fit’ and 100m+

‘good fit’

Sonoma Co lakes

features

Feature to raster

StreamGrid

Reclass grid 1 cat

Overlay

HydroGrid

Overlay

Select/Query vineyard

suitable soils

“Good Soil” Feature

Feature to raster

“Good Soil” raster

Lake Grid

Sonoma Co Soils features

Overlay

“Aggie land” raster

“Aggie land” raster

Overlay

“Good surface” raster

OverlayLand suitability for vineyard development within 100m+ buffer zone ‘good fit’

Calculate112≤[Aspect]≤337

Flowchart 3 - Test

Existing Vineyards (1997) features

Existing Vineyards (1997) raster

Overlay

Result: 23854 of Land suitability for vineyard development patches out of 80612 or 29.5% overlapped with Existingnvineyards (1997) – raster

Feature to raster

Raster to feature

Select by location all Potential land for

vineyard development – features that are

crossed by the outline of Existing vineyards

(1997) – features

Existing Vineyards (1997) features

Potential land suitable for developing a

successful vineyard !feature

Potential land suitable for developing a

successful vineyard ! (Raster)

Potential land suitable for developing a

successful vineyard !(Raster)

Select by attribute Suitable values

Value 1

New layer of suitable features

Result: 771 Potential land for vineyarddevelopment – features out of 2640 or

29.2% were crossed by the outline of Existing vineyards (1997) – features

Select by location all Existing vineyards

(1997) – features that are crossed by the outline of Potential land for vineyard

development – features

Result: 1078 Existing vineyards (1997) – features out of 3036 or 35.5% were crossed by the outline of Potential land for vineyard development – features.

Vector Final Analysis Raster Final Analysis

Sonoma County, CA Elevation for Vineyards

Sonoma County, CA Slope and Aspect for Vineyards

Buffer zones from water source and surface to identify potential land

Potential suitable land for Vineyard development

Test of final output data w/existing dataset

Data Sources• California Spatial Information Library

- Regional 30m 7.5' x 7.5' DEM

1:24,000 dataset

- California Hydrography dataset

- California counties dataset

• The California Department of Forestry and Fire

Protection's Fire and Resource Assessment Program (FRAP)

- California Landuse dataset

• USDA NRCS (Natural Resources Conservation Service) Soil Data Mart

- Sonoma County, CA Soils dataset

• The Russian River Interactive Information System

- Existing Sonoma County vineyards survey (1997)

Analysis Results• Feature to raster Convert Existing vineyards (1997) -features dataset to a raster: Existing vineyards (1997) - raster

• Overlay Land suitability for vineyard development with Existing vineyards (1997) – raster [Land suitability for vineyard development] & [Existing vineyards (1997) – raster] Result: 23854 of Land suitability for vineyard development patches out of 80612 or 29.5% overlapped with Existing vineyards (1997) – raster.

• I also did a vector analysis out of curiosity: Raster to features Convert Land suitability for vineyard development to polygon features: Land suitability for vineyard development – feature yielded (1 - suitable, 0 -unsuitable)

• Select by attributes all Land suitability for vineyard development – feature that are suitable (have a value of one)

• Make new layer of selected features: Potential land for vineyard development – feature

• Select by location all Potential land for vineyard development – features that are crossed by the outline of Existing vineyards (1997) – features

Result: 771 Potential land for vineyard development – features out of 2640 or 29.2% were crossed by the outline of Existing vineyards (1997) – features

• Select by location all Existing vineyards (1997) – features that are crossed by the outline of Potential land for vineyard development – features

Result: 1078 Existing vineyards (1997) – features out of 3036 or 35.5% were crossed by the outline of Potential land for vineyard development – features.

Challenges

Difficulties I encountered during the modeling process (and glad I learned!) were how to define and re-project geographic coordinate systems for consistent map analysis between datasets, having to figure out how to combine two DEMs by performing a mosaic. Also a challenge at times was carefully implementing map algebra statements in the raster calculator. An extra space or layer name dash in a conditional statement would yield errors, and outputs with no values. Though I conclude that my model did not pass the validation test when compared to the existing vineyards dataset with the resulting percentages above, this was a great learning experience, from searching for datasets to using map algebra.

Limitation of model

• I do not have expert knowledge in the viticulture field. Upon searching for data I came across companies whose professional services are focused on using GIS for developing vineyards with soil scientists on staff for conducting private soil surveys, and also viticulture scientists for cutting edge wine growing techniques and technologies. It is a well developed industry.

• Coming across current data is difficult, for example land use data, and I can also imagine that more vineyards have been developed since 1997.

• Certain datasets are not available or are for purchase, such as climatic data for regional wind data and regional temperatures.

Future Improvements

• Conduct interviews with vineyard developers for more criteria parameters and maybe more current datasets.

• Research on using geostatistical techniques to obtain more precise results and

maybe obtain more relevant results.