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Project Overview – Ecuador NASA-2
Modeling the Scale Dependent Drivers
of LCLU Dynamics in Northeastern Ecuador: Simulating Patterns
of Landscape Change and Assessing their Cause and Consequence
through Multi-Level Models and Cellular Automata
Funding Agency:
NASA
Begin Date: March 1, 2003
End Date: April 30, 2006
Research Symposium in Quito, Ecuador - June 10, 2004
Click
here to view a description of the symposium conducted by the Ecuador
Project team in Quito on June 10, 2004.
As a continuation of the NASA-1
project, this project attempts to further delve into the factors
related to changing land cover and land use (LCLU) in the northern
Oriente of Ecuador. Exciting new methods are tested that provide
greater insight into the various LCLU dynamics in the Amazonian
region.
Using longitudinal household survey data collected in 1990 and
1999, a 2000 community survey, a multi-resolution remote sensing
time-series, GIS coverages of resource potentials and endowments,
and field verification and geodetic control data, we analyze the
determinants of changes in LCLU at the plot, sector, and regional
levels, and for annual and decadal periods. The fundamental research
questions revolve around (a) the rates, patterns, and mechanisms
of forest conversion to agricultural and urban uses; (b) the relative
importance of exogenous and endogenous variables on these land uses;
(c) the associated scale dependent drivers of LCLU dynamics and
patterns operating across socio-economic and demographic, biophysical,
and geographical domains; (d) rate and pattern of land conversion
from forest to agricultural crops, pasture, secondary plant succession,
and urbanization, as well as the rate and pattern of land abandonment
at the farm level; and (e) plausible scenarios of future land cover
change and their policy implications as assessed through multi-level
models that are responsive to multi-scale effects as well as spatial
simulations of LCLU dynamics through a
cellular automata (CA) approach.
The survey periods and the assembled satellite time-series images
serve as our reference dates that are integrated to define relationships
through (1) multivariate logit models of LCLU for 1990, 1999, and
for changes between those two survey periods; (2) satellite image
classifications and change-detections of LULC dynamics, space-time
trajectories of pixel histories, and pattern metrics of landscape
organization to define LCLU composition and spatial structure; (3)
LCLU simulation through cellular automata, informed by the satellite
and multivariate models of LCLU change, to create spatial simulations
of LULC dynamics; and (4) multi-level models to integrate variables
and effects from multiple scales into an integrated model of LCLU
dynamics to assess the scale dependence of variable interactions
on LCLU patterns.
The analysis is framed within a dynamic systems approach that emphasizes
non-linear relationships, feedback mechanisms, and critical thresholds
in population-environment interactions. Theoretical foundations
include principles involving the interplay of political ecology,
human ecology, landscape ecology, and complexity theory.
The multi-level models are used to integrate household, community,
and regional variables that impact household decision-making and
hence the mapped LCLU patterns at the farm level. The spatial simulations
are developed through CA approaches at the annual and decadal scales.
Linear and non-linear responses or “critical landscapes”
are studied to model the ecological responses to a range of spatial
patterns of LCLU derived through hypothetical, modeled, and observed
conditions. The multi-level models are assessed through statistical
measures of model performance, whereas the derived CA patterns are
compared to the actual patterns represented in the satellite time-series
and assessed through image change-detections, change trajectories
or pixel histories, and summary correlations and pattern metrics
for comparisons of expected vs. observed LCLU patterns. System behaviors
are interpreted within a policy-relevant context by comparing simulated
LCLU scenarios to targeted land management outcomes. Multiple LCLU
change scenarios are developed around defined policy goals. Model
convergence and variable sensitivity are examined relative to the
LCLU patterns, model variables, and policy goals and expectations.
The basic intent of this research is to assess the rate, pattern,
and mechanisms of forest conversion to agricultural and urban land
uses by examining the scale dependent drivers of LCLU dynamics of
the Ecuadorian Oriente so that models of household decision-making
regarding LCLU dynamics can be derived through the integration of
exogenous and endogenous variables that operate within space-time
scales and represent socio-economic and demographic, biophysical,
and geographical domains, linked to a satellite time-series view
of landscape change. Using such models and satellite views of LCLU
change, multilevel models will integrate space-time scales as well
as global, regional, and local effects, and spatially-explicit simulations
of LCLU change will be derived using rules and weights of variable
behavior and interactions derived through the empirical models,
neighborhood conditions, feedback and threshold relationships, and
initial conditions. The spatial simulations will be space-time sensitive
and policy relevant. To accomplish the above set of goals, the following
research aims will rely upon our previous data collection and preliminary
research findings to bridge to the more integrated modeling that
will consider population-environment interactions as cause and consequence
of LCLU dynamics.
There are five primary research aims that we hope to address in
this project.
- Exogenous Impacts & Relationships:
Does LCLUC (land use and land cover change) respond in a linear
or non-linear way to changes in commodity prices, new or improved
infrastructure, in-migration and population growth, institutional
policies, or extensions of the road network? Feedbacks may produce
a system with a critical point, subject to small or large periods
of incremental change in such exogenous factors functioning with
time lags. Determining what are the key external factors, examining
feedbacks and lags, and identifying thresholds of change are critical
for the analysis of system behavior and the effects of context
on LCLUC. This can lead to the re-formulation of social and environmental
policies that are otherwise usually assumed to have linear effects,
and exogenous effects might also serve as shocks that may destabilize
the region and introduce a dynamic equilibrium condition to the
changing LULC pattern.
- Migrant Colonists & LCLU Dynamics:
What are the rates and scale dependencies of different types of
land conversions at the finca, sector and regional levels? Typical
land conversion types include forest-to-crop, forest-to-pasture,
forest-to-urban, forest-to-barren, crop-to-pasture, crops-to-urban,
pasture-to-secondary forest, pasture-to-urban, barren-to-secondary
forest, and barren-to-crops. It is likely that conversion rates
vary across scales from the finca to the region. It is also likely
that conversion rates change over time and that the spatial and
temporal considerations are conversion-type specific. What are
the socio-economic and demographic, biophysical, and geographical
factors and processes that drive land-use/land-cover conversion
characteristics? Socio-economic and demographic factors include
family size and demographics, educational level, past agricultural
experience, family life cycle, duration of residence, economic
status; biophysical factors include soil conditions, topography,
water supply, surrounding land uses, existing LCLU characteristics
at time of settlement; and geographical factors include proximity
to a road, proximity to a town, proximity to a school, size of
local market, and access to banks (credit and loans).
- Multivariate Models of LCLU & LCLUC:
What (parsimonious) set of socio-economic and demographic, biophysical,
and geographical variables best explain LCLU, LCLUC, and plant
biomass variation? What is the nature of the spatial autocorrelation
(or degree of randomness) across spatial scales, including cell
resolutions? How stable are multivariate models developed for
the current landscape for other time periods and for other regions?
What land units and spatial aggregations are the most useful for
characterizing the composition and spatial organization of LCLU
types within the Oriente? What are the interrelationships between
system stakeholders in terms of LCLU dynamics in a context where
deforestation, agricultural extensification, secondary plant succession,
and urbanization are all occurring in response to population in-migration,
road building, and the expansion of the market economy? How does
development and the emergence of and growth of towns in a central
place hierarchy affect LCLUC? What is the form of multi-level
models that seek to integrate multi-thematic variables across
space and/or time scales, and what are the structure of the spatial
autocorrelation and the nature of the autoregressive terms in
the models to account for this effect of location on the ordering
of data?
- Spatially-Explicit, Dynamic Simulations of LCLUC:
Develop a cellular automata (CA) system to generate LCLU simulations
based upon actual conditions observed through the satellite image
time-series and extended in time and space through observed rules
and interactions between neighbors. The empirical models of LCLUC
from the longitudinal survey data will be used to inform the CA
models by generating weights and rules of behavior in the model.
As well, the satellite time-series and the image change-detections
and pixel history or trajectory work will also inform the CA models
by imposing preferred pattern, and settlement trajectories, deforestation
and reforestation pathways, and in short, landscape behavior to
socio-economic and demographic, biophysical, and geographical
conditions and characteristics for the simulation of LULC dynamics
over time and throughout the region. Among the research questions
to be considered include the following: are the rates and patterns
of LCLUC non-linear due to feedbacks between the process of change
and the existing patterns of land use and land cover? Do spatial
patterns of LCLU cause a change in the fitness of the weighting
of the transition probabilities? What are the LCLU patterns at
year 2025 and at other selected time frames when LCLU dynamics
are simulated using variables representing the socio-economic
and demographic, biophysical, and the geographical domains? Are
feedbacks between human activities and ecological dynamics non-linear?
How can the science of complexity be used to understand how simple,
fundamental processes combine to produce complex holistic systems?
How can non-equilibrium systems, with feedbacks leading to non-linearity,
evolve into systems that exhibit criticality, and thereby capture
key elements of the dynamics of LCLU in the Amazon? What are the
emerging patterns or trajectories of LCLUC across the satellite
time-series, and do they represent LCLU patterns indicative of
agricultural extensification or intensification, and how much
secondary plant succession is occurring and why?
- Policy-Relevant Scenarios & LCLUC Simulations:
What are the effects of continuing petroleum exploration and extraction
and road building on future in-migration of spontaneous colonists
to both farm plots and towns? What are their effects on deforestation
and land conversions at the finca, sector, and regional scales?
How do land management-targeted outcomes of LCLU by strata compare
to the LCLUC simulations? What are the implications for LCLUC
in terms of government services (e.g., land titles, credit, agricultural
extension), infrastructure (especially road development but also
schools, health clinics), and institutional development (markets,
community organizations, local leadership and policies) in the
region? What have been the effects of the creation of the large
Yasuni National Parks and the Cuyabeno Nature Reserve within the
region on LCLU dynamics within the Oriente and lands adjacent
to these conservation areas? How can information on human dynamics
and LCLU dynamics be related to policy-relevant research by having
the policy analysis contextually inform the research and contribute
to policy formation at the national, regional, and local levels?
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