Land Use Classification and Deforestation Detection in Southwestern - - PowerPoint PPT Presentation

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Nov 10, 2022 403 likes •594 views

Land Use Classification and Deforestation Detection in Southwestern Nicaragua B Y : C A S S A N D R A R I V A S , O P H E L I A W A N G , A N D B O S T E V E N S N O R T H E R N A R I Z O N A U N I V E R S I T Y Introduction/Background

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B Y : C A S S A N D R A R I V A S , O P H E L I A W A N G , A N D B O S T E V E N S N O R T H E R N A R I Z O N A U N I V E R S I T Y

Land Use Classification and Deforestation Detection in Southwestern Nicaragua

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Introduction/Background

 Rapid land use change in the tropics

 Deforestation  Fragmentation  Environmental degradation

 Determining current land use and temporal change

is important

 Sustainable conservation and restoration planning

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Research Objectives and Questions

 Objective: To delineate areas of vulnerability to

change in SW Nicaragua, specifically areas of deforestation and natural regeneration between the years of 2000-2009 in order to inform future conservation and restoration efforts in the region.

 What are the land use patterns revealed in the land

use/cover classification?

 How have the land use patterns changed since the

year 2000?

 What are the current vulnerable areas of change?

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Methods: Study Area

 Rivas Isthmus  Paso del Istmo  Ecosystems include:

Dry-tropical forests, moist forested areas, and coastal mangroves

 Other land cover types

include: Pasture, plantation, crops, and urban

(Map sources: ArcMap 10.1; Paso Pacifico.org)

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Methods: Field Data Collection & Classification

 Ground Referencing Data

Collection

 Digitize roads and access

points

 398 data points collected;

assessed cover data at each point

Imagery SPOT, collected Jan-Feb 2009 Classification Manual training polygons ENVI 4.7 RuleGen (Quest) Final Classes:

Wetland
Urban
Crop
Pasture
Plantation
Young Regrowth
Old Regrowth
Young Secondary Forest
Old Secondary Forest

Accuracies and Kappa statistics

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Methods: Change Detection & Cluster Analysis

 Land-use/cover classification

2000 (Sesnie et al. 2008)

 Post-classification change

detection in ENVI

 Classification preparation for

change detection analysis

 Plantation

 Hotspots/cold spots of change

 Cluster and Outlier Analysis

using Moran’s I

 Neighborhood clustering score

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Final 2009 Classification

Over all accuracy is 87.68%
Producers accuracies range

76.16-95.63%

Users accuracies range

76.34 - 95.52 %

Khat scores– overall and all

individual classes except for wetland-mixed and old regrowth are in strong agreement

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Forest Change (2000-2009)

10 20 30 40 50 60 Crop Pasture Regrowth Plantation Forest Change (%) Class Type

Forest Change

No Change

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Forest to Pasture

Hotspots of change occur in the

Northcentral part of the isthmus

Also in the southern region where

last large tracks of forest occur despite rugged terrain

Cold spots occur throughout region

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Forest to Regrowth

Hot spots occur in pockets along

the rugged Pacific mountains

Cold spots occur in throughout

the intense topography

At some point this forest was

converted into another class and now regrowing

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Forest to Plantation

Hotspots occur in a few pockets to

the north and in the agricultural lake side area

Cold spots occur in the southern

area where old secondary forest remain*

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Regrowth Change (2000-2009)

5 10 15 20 25 30 35 40 45 50 Crop Pasture Regrowth Plantation Forest Change (%) Class Type

Regrowth Change

No Change

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Regrowth to Pasture

Change is scattered throughout

and is prolific

Reveals the strong influence of

this class in the area

Hot spots are specifically located

in the north central region

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Regrowth to Forest

Hotspots are taking place in the

southern part of the isthmus

Important for increasing forest

near other older forest

Reveals the change in the area

despite rugged topography

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Discussion

 Change Detection

 50% of the secondary forest was converted into other classes  Deforestation is still occurring at a high rate approximately

5.6% per year

 Regrowth is converted mainly to pasture (prevailing force)  However, is also maturing into secondary forest (23%)

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Conclusions

 Future conservation efforts should utilize this data for a more

comprehensive conservation assessment

 Deforestation and rapid land use change is continuing to

ccur throughout this dynamic landscape

 Conservation and restoration efforts must be efficient given

limitations

 Cluster (hotspot/coldspot) analysis helped in defining specific areas of

change

 This study is a unique example of leveraging resources and

collaboration to assess land use change for practical conservation

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