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DDetermining rangeland suitability etermining rangeland suitability for cattle grazing based on for cattle grazing based on

ddistance-to-water, terrain, and istance-to-water, terrain, and soilssoils

MGIS Capstone Project - Peer Review

July 8, 2008

Dennis Oberlie, Wyoming Game & Fish Dept.

Academic Advisor: Joseph A. Bishop, Ph.D.,

Penn State University, Department of Geography

GoalGoal

Develop a user-friendly GIS model using ESRI software to determine rangeland grazing suitability for cattle

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Presentation OutlinePresentation Outline

Where?Who?Why?What?How?

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ExampleHow to ImproveObjectivesIssuesProceduresFuture ApplicationsQuestions

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–Wyoming– Bureau of Land

Management (BLM)

– Lander Field Office

WhereWhere

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WhoWho

Bureau of LandManagement

(BLM)

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– Grazing major use of public rangelands– Determine lands available for grazing– Determine appropriate numbers of

livestock– Manage for uniform grazing to prevent

land degradation

WhyWhy

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Factors used to determine grazing suitability

Terrain and slope

Distance-to-Water

WhatWhat

WhatWhat

Terrain

– 0 to 10% Slope Suitable– 30% Slope 50% Suitable– Over 60% Slope Unsuitable

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Distance-to-Water

0 – 1 mile 100% use

1 - 2 miles 50% use

Over 2 miles No use

WhatWhat

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HowHow

Two Current Methodologies

1. Holechek (1988, 1998)– developed during the “infancy” of GIS – 4 reduction categories– determine percent reduction of area

available for grazing– most existing determinations use this

method

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HowHow

2. Guenther et al. (2000)– Uses GIS (IDRISI software from Clark

Labs)– 5 suitability categories– determine % of area suitable for

grazing (Inverse of Holechek)

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Sweetwater Canyon Example

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How to Improve Current MethodsHow to Improve Current Methods

Develop systematic computer-based methodology

Create a barrier-to-movement layer

Consider vegetation capability of soils

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Barrier-to-MovementBarrier-to-Movement Use slope > 60% to create

barrier layer Calculate shortest distance

to water around barrier

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SoilsSoils

Suitable for vegetation Rock outcrops

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Project GoalProject Goal

Develop a user-friendly GIS model using ESRI software to determine rangeland grazing suitability in the Lander Field Office of the Bureau of Land Management

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Project ObjectivesProject Objectives

Develop a GIS Grazing Suitability Model using ESRI Tools to create an automatic process with minimal user inputs

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Project ObjectivesProject Objectives

Develop a GIS Grazing Suitability Model using ESRI Tools to create automatic process with minimal user inputs

Compare GIS based analysis with existing (paper map) calculations and to verify modifications with local rangeland experts

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Project ObjectivesProject Objectives

Develop a GIS Grazing Suitability Model using ESRI Tools to create automatic process with minimal user inputs

Compare GIS based analysis with existing (paper map) calculations to verify modifications with local rangeland experts

Develop summary to explain methodology and data

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Data Availability IssuesData Availability Issues

Water sources layer– Seasonal water sources–Man-made sources not consistently mapped

Fences– Incomplete and out-of-date

Soil mapping– Detail of mapping units

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ProceduresProcedures

Clip all layers to Pasture Bdry

Elevation

Rivers

Pond/Lakes

WaterWells

Soils

Calculate Slope

Classify by Slope

Create SlopeBarrier Layer

Merge Water

SourcesUpdateWater

Sources

Classify by Distance-To-

WaterAround Barrier

Layer

Classify by soil suitability

Sum Slope and D-T-W Classification for

Total Suitability

Union Suitable Soils with Total

Suitability

CalculateAcres and

% Suitable

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ScheduleSchedule

July 08

Aug Sep Oct Nov Dec Jan09

Feb Mar Apr May

Finish ClassFinish Class

Develop Model & UpdateDevelop Model & Update

Present to WySRMPresent to WySRM

Future ApplicationsFuture Applications

Use model for a Decision Support System– New water sources– Additional fencing–Monitoring plans

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Future ApplicationsFuture Applications

Use model for a Decision Support System– New water sources– Additional fencing–Monitoring plans

Other factors to include in model– Vegetation– Conflicting land uses

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ThanksThanks

Wyoming Game and Fish DepartmentStaff of the Bureau of Land Management

- Lander Field OfficeJoe BishopDoug MillerBeth KingAnd most importantly–My Wife

How to test the model

• Validate the success and utility of this project

Your Questions/Input

Contact Dennis Oberlie : duo105@psu.edu