Transcript 第三部分 approaches to solving conservation problems

第三部分
Approaches to solving
conservation problems
鄭先祐(Ayo)
國立台南大學 環境與生態學院 教授
[email protected]
Brief contents I
 Unit I Conceptual foundations
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(基礎觀念)
Chap. 1. What is conservation biology?
Chap. 2. Global biodiversity
Chap. 3. Threats to biodiversity
Chap. 4. Conservation values and ethics
Chap. 5. Ecological economics and nature
conservation
 Unit II Focus on primary threats to
biodiversity (對生物多樣性的威脅)
 Unit III approaches to solving conservation
problems (化解保育問題的途徑)
Groom, M. J., G. K. Meffe, D. R. Carroll (2006) Principles of
conservation. 3rd edition. Sinauer Associates, Inc.
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Brief contents II
 Unit I 基礎觀念
 Unit II 對生物多樣性的威脅
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Chap.
Chap.
Chap.
Chap.
Chap.
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6. Habitat degradation and loss
7. Habitat fragmentation
8. Overexploitation
9. Species invasions
10. Biological impacts of climate change
11. Conservation genetics
 Unit III approaches to solving conservation
problems (化解保育問題的途徑)
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Unit III 化解「保育問題」的途徑
 12 species and landscape approaches to
conservation (物種與地景途徑)
 13 ecosystem approaches to conservation:
responses to a complex world (生態體系途徑)
 14 protected areas: goals, limitations and design
 15 restoration of damaged ecosystems and
endangered populations (復原生態學)
 16 sustainable development (可持續發展)
 17 the integration of conservation science and
policy (科學與政策的整合)
 18 meeting conservation challenges in the 21th
century (新世紀的挑戰)
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Species and Landscape
approaches
鄭先祐(Ayo)
國立台南大學 環境與生態學院 教授
[email protected]
Contents
1. Introduction
2. Populations and how they change
3. Modeling approaches for prediction
and conservation planning (預測與保育規劃)
4. Challenges and opportunities of
conservation at the landscape scale
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Supplements I
 Essay 12.1 metapopulations, extinction
thresholds, and conservation
 Essay 12.2 population viability analysis and
conservation decision making
 Essay 12.3 ecologically functional
populations
 Essay 12.4 landscape-level conservation for
the sea
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Supplements II
 Case study 12.1 assessing extinction risk in
neotropical migratory songbirds: the need
for landscape-based demographic models
 Case study 12.2 landscape conservation in
the Greater Madidi landscape, Bolivia:
planning for wildlife across different scales
and jurisdictions
 Case study 12.3 putting the pieces together:
preserving cranes and their habitats around
the world
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Species and landscape approaches
 Most efforts aimed at conserving
biodiversity have focused on protecting
individual populations or species, although
the means pursued usually involve
conservation of habitat.
 On a global scale, the IUCN’s Red List of
threatened species focuses worldwide
attention on threats at the species level.
 The Convention on International Trade in
Endangered Species (CITES)
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Populations and how they change
 Conservation biologists can track changes
in populations by using principles and
techniques of population demography.
 These four factors, birth, immigration,
death and emigration, are often referred to
as the BIDE factors.
 Life history characteristics, sex ratio, ageor stage-structure, time of first
reproduction,
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Mechanisms of population regulation
 Density-independent factors
 Density-dependent factors
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Special problems of very small populations
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Natural catastrophes
Inbreeding
Demographic uncertainty
Environmental uncertainty
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source-sink concepts and their
application to conservation
 A population that consists of several
subpopulations linked together by
immigration and emigration is called
a metapopulation.
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Fig. 12.6 A schematic
example of a metapopulation structure
affected by sourcesink dynamics.
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Metapopulation concepts, threshold
responses and conservation
 Rescue effect, the subpopulation in each
patch can fluctuate in size, and when a
subpopulation is very small, local extinction
can be prevented by occasional immigrants
that arrive from neighboring patches.
(Brown and Kodric-Brown, 1977)
 The rescue effect may also be important in
maintaining high levels of species
diversity.
 例：Cougar(美洲獅) (Felis concolor) population of
the Santa Ana moutains of souther Califrnia.
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 A metapopulation simulation model showed
that the overall population in the region is
heavily dependent on movement by
individual cats through the corridors to
colonize empty areas.
 One of the first theoretical analyses to
consider the persistence of metapopulations
is that of Hanski et al. (1996) who estimated
“minimum viable metapopulation size” (the
number of subpopulations required to
support metapopulation persistence). (essay
12.1)
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Modeling approaches for prediction
and conservation planning
 Population viability analysis (PVA),
examines the demographic effect of
different threats or management practices
on a population, or set of populations, by
projecting into the future.
 PVA is a quantitative risk analysis aimed at
refining our understanding of the factors that
influence population fate.
 To generate a prediction of extinction risk.
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Essay 12.2 PVA and conservation
decision making
 Count-based PVAs
 Treat all individuals in the populaiton as
though they were identical.
 Demographic PVAs
 Species in which individuals differ
substantially in age, size, developmental
stage, social status, or any other
attribute
 Structured PVAs
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Table A potential uses of PVA “products”
 Assessment of extinction risk
 Shaffer 1981, Shaffer and Samson 1985, Lande
1988, Forsman et al. 1996, Menges 1990,
Allendorf et al. 1997, Menges and Gordon 1996,
Gerber et al. 1999
 Guiding management
 Shaffer 1981, Armbruster and Lande 1993,
Bustamante 1996, Howells and Edwards-Jones
1997, Marshall and Edwards-Jones 1998, South
et al. 2000, Nantel et al. 1996, Ratsirarson et al.
1996, Tufto et al. 1999, Caswell et al. 1998,
Menges 1990, Lindenmayer and Possingham
1996
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The value of Hierarchical analysis for
understanding population change
Fig. 12.10 population dynamics
should be understood as resulting
from a hierarchy of processes
affecting populations at different
levels.
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Landscape models for conservation
 Because populations in the various patches are
linked by movement of dispersing individuals,
the fates of the populations are interconnected.
 The landscape approach recognizes the
interconnectedness of populations and
incorporates this concept into models and
management plans.
 The growth, or lack thereof, of the population
is determined not only by the quality of the
individual microsites occupied, but also by the
spatial and temporal distribution of suitable
and unsuitable microsites or patches of habitat.
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Fig. 12.11 distribution of suitable breeding habitat for
Bachman’s sparrow in (A)1970, (B) 1990, and © 2010
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Spatially explicit population models
 Spatially explicit population models (SEPM),
incorporate the actual locations of
organisms and suitable patches of habitat,
and explicitly consider the movement of
organisms among such patches.
 Three major elements: a landscape map, a
scenario of how the landscape will change in the
future and a population dynamics simulation.
 GIS (geographic information systems)
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Challenges and opportunities of
conservation at the landscape scale
 As landscape become increasingly
dominated by human-altered habitats,
conservationists not only need to evaluate
the viability of species across a large spatial
scale, but also to project ecological, social,
and economic influences that will alter how
humans interact across the landscape.
 Tracking changes in human use (such as landuse change or decreases in the trophic level
targeted by fisheries)
 Alternative-future analysis
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Alternative-futures analysis
 Makes use of spatially-explicit(清晰的)
landscape-scale projections of several distinct
options for future development within a region
and predicts socioeconomic and biodiversity
outcomes of each option.
 A consortium of conservation biologists, city
and regional planners, and local citizens work
together to examine probable consequences of
distinct decisions visually through an iterative
process of creating and analyzing integrative
landscape maps of change and impact.
 Alternative futures?
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Fig. 12.13 the alternative-futures analysis process for the
Willamette River Basin.
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Fig. 12.15 combining a
human and biological
landscape reveals areas
of threat to a landscape
species, as well as areas
that are already well
protected.
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Supplements II
 Case study 12.1 assessing extinction risk in
neotropical migratory songbirds: the need
for landscape-based demographic models
 Case study 12.2 landscape conservation in
the Greater Madidi landscape, Bolivia:
planning for wildlife across different scales
and jurisdictions
 Case study 12.3 putting the pieces together:
preserving cranes and their habitats around
the world
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問題與討論
http://mail.nutn.edu.tw/~hycheng/
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