Open Journal of Forestry
2012. Vol.2, No.4, 265-271
Published Online October 2012 in SciRes (http://www.SciRP.org/journal/ojf) http://dx.doi.org/10.4236/ojf.2012.24033
Copyright © 2012 SciRes. 265
Forest Fragmentation and Its Potential Implications in the
Brazilian Amazon between 2001 and 2010
Izaya Numata, Mark A. Cochrane
Geographic Information Science Center of E xcell en ce , S ou th D ak ot a State University, Brookings, USA
Email: Izaya.numata@sdstate.edu
Received August 12th, 2012; Revised September 17th, 2012; Accepted September 30th, 2012
In recent decades, human development pressures have results in conversions of vast tracts of Amazonian
tropical rain forests to agriculture and other human land uses. In addition to the loss of large forest cover,
remaining forests are also fragmented into smaller habitats. Fragmented forests suffer several biological
and ecological changes due to edge effects that can exacerbate regional forest degradation. The Brazilian
Amazon has had greatly contrasting land cover dynamics in the past decade with the highest historical
rates of deforestation (2001-2005) followed by the lowest rates of forest loss in decades, since 2006. Cur-
rently, the basin-wide status and implications of forest fragmentation on remnant forests is not well
known. We performed a regional forest fragmentation analysis for seven states of the Brazilian Amazon
between 2001 and 2010 using a recent deforestation data. During this period, the number of forest frag-
ments (>2 ha) doubled, nearly 125,000 fragments were formed by human activities with more than 50%
being smaller than 10 ha. Over the decade, forest edges increased by an average of 36,335 km/year.
However, the rate was much greater from 2001-2005 (50,046 km/year) then 2006-2010 (25,365 km/year)
when deforestation rates dropped drastically. In 2010, 55% of basin-wide forest edges were < 10 years old
due to the creation of large number of small fragments where intensive biological and ecological degrada-
tion is ongoing. Over the past decade protected areas have been expanded dramatically over the Brazilian
Amazon and, as of 2010, 51% of remaining forests across the basin are within protected areas and only
1.5% of protected areas has been deforested. Conversely, intensive forest cover conversion has been oc-
curred in unprotected forests. While 17% of Amazonian forests are within 1 km of forest edges in 2010,
the proportion increases to 34% in unprotected areas varying between 14% and 95% among the studied
states. Our results indicate that the Brazilian Amazon now largely consists of two contrasting forest con-
ditions: protected areas with vast undisturbed forests and unprotected forests that are highly fragmented
and disturbed landscapes.
Keywords: Amazon; Forest Fragmentation; Forest Degradation; Conservation
Introduction
Amazonian forests have undergone extensive land cover
changes over the past decades, presenting the highest rates of
deforestation among the Pan Tropic region (Archard et al.,
2004; Hansen et al., 2008; Baccini et al., 2012). Forest conver-
sion into land use in this region has affected regional and global
ecosystems including climate, hydrology and carbon fluxes
(Defries et al., 2002; Asner et al., 2005; Coe et al., 2009; Soares
et al., 2010; Numata et al., 2011). Deforestation also fragments
contiguous forests into smaller and smaller pieces, inducing
ecological and biological changes in forest ecosystems ( Love joy
et al, 1986; Nascimento et al., 2004; Laurance et al., 2011). As
a result, vast areas of remaining but fragmented forests in
Amazonia are threatened to forest degradation.
The effects of forest fragmentation vary primarily as func-
tions of edge penetration distance, spatial arrangements and
time of persistence of forest fragments (Laurance et al., 1997,
2007). Edge effects on fragmented forest ecosystems cause
numerous changes across varying edge penetration distances
such as the reduction of biodiversity, changes in forest structure
and specie composition, the increase of fire vulnerability, al-
ternation of hydrological and carbon cycles, elevated tree mor-
tality and canopy desiccation (Lovejoy et al., 1986; Lauran ce et
al., 1998; Fahlig, 2003; Cochrane, 2003; Cochrane & Laurance,
2002, 2008; Nascimento et al., 2004; Briant et al., 2010). And
these edge associated changes can expand across large areas.
For example, potential carbon emissions from biomass collapse
in edge forests of 100 m as a result of fragmentation may reach
around 3% of those from deforestation in the Amazon region
(Numata et al., 2011). Canopy desiccation in tropical dry forest
in eastern Amazonia, was observed up to 2.7 km into frag-
mented forests based upon satellite data (Briant et al., 2010).
However, the degree of forest fragmentation and potential edge
effects are also highly variable across the Amazon region
(Laurance et al., 2007, 2011; Phillip et al., 2006).
Dynamics of forest edges in landscapes are linked to ongoing
deforestation (Skole & Tucker, 1993; Ferraz et al., 2006; Nu-
mata et al., 2009). Forest cover change in the Brazilian Amazon
has intensified since the mid 1990s and from the late 1990s to
the first half of the 2000s was remarked with the highest his-
torical rates of deforestation due to increasing demand of live-
stock and agricultural products (Nepstad et al., 2006; Morton et
al., 2006; Barona et al., 2010). On the other hand, deforestation
has been greatly reduced since 2006 in part due to economic
downturn but also by environmental law enforcements imple-
mented by the Government of Brazil in addition to the expan-
I. NUMATA, M. A. COCHRANE
sion of protected areas (Nepstad et al., 2009; Barreto & Silva,
2010; Soares et al., 2010). According to Soares et al. (2010),
54% of remaining forests in the Brazilian Amazon were under
protection in 2009 and the expansion of protected area can con-
tinue in the future. Therefore, actual areas subject to deforesta-
tion or disturbance would be less than half of the existing re-
maining forests. Nevertheless, the rate of Amazonian deforesta-
tion continues to decline, and by 2010, 7000 km2 of forest was
cleared, the lowest rate since the monitoring of deforestation
started (INPE, 2012). These two contracting deforestation pat-
terns in the past decade should have resulted in different spatial
and temporal dynamics of forest fragments and edge effects on
remaining forests across the Amazon. Given the interactions
between socio-economic and political driving forces towards
land cover changes in the Amazon, the dynamics of forest
fragments become very complex and variable in space and time
(Arima et al., 2008; Numata et al., 2009).
Amazonian forests prone to edge effects within 1 km of for-
est edge was 150% larger than its own deforested areas in the
late 1980s (Skole & Tuker, 1993) and further intensive forest
cover changes since then have introduced vast amounts of for-
est edges into Amazonia (Broadbent et al., 2008; Numata et al.,
2011). On the other hand, the magnitude and intensity of edge
effects varies according to its spatial attributes such as fragment
size and shape, the amount of edge in a landscape as well as the
persistence of forest edges (Fahrig, 2003).The updated knowl-
edge on forest fragmentation is indispensable in order to esti-
mate its regional impacts as well as the synergetic effects with
other disturbances such as forest fire, climate change and man-
agement (Laurance et al., 2001; Cochrane, 2003; Cochrane &
Laurance, 2008). However, the current status of forest frag-
mentation in Amazonia is not well known.
We perform the basin-wide assessment of forest fragmenta-
tion by analyzing the spatial and temporal dynamics of forest
fragments in seven states of the Brazilian Amazon and discuss
its potential implications for Amazonian ecosystems and the
effects of land cover changes and the expansion of protected
areas for the 2001-2010 time period.
Data and Methodology
For the analysis of deforestation and forest fragmentation,
the INPE PRODES digital product developed by the Brazilian
Institute of Space Research (INPE) was used in this study. This
data provides a spatially explicit map of annual deforestation in
the Brazilian Amazon since 1997 (Figure 1). The details about
the methodology of the PRODES data are found in
www.obt.inpe.br/prodes/metodologia.pdf. We considered the
year 2001 is the starting year for our temporal analysis for the
2001-2010 period and deforestation prior to 2001 was con-
sidered as old deforestation. The PRODES data used in this
study has 90 m pixel size or 0.81 ha per pixel. This study cov-
ers seven of the nine states of the Legal Amazon: Acre, Amapá,
Amazonas, Mato Grosso, Pará, Rondônia and Roraima (Figure
1). Since only small portions of Maranhão and Tocantins, the
other states of the Legal Amazon, are covered in the PRODES
data and several artifacts and errors exist over Maranhão, these
two states were not included in our analysis. Besides, because
of a lack of good satellite imagery due to frequent cloudiness in
a p or ti on o f t he e astern Amazon region (Pará), an area of 25,290
km2 was eliminated from the analysis. Our study region covers
4,5000,000 km2 of the Brazilian Amazon. From this data,
Figure 1.
The Brazilian Amazon with seven states: Acre (AC), Amapá (AP),
Amazonas (AM), Mato Grosso (MT), Pará (PA), Rondônia (RO), and
Roraima (RR) (2010 INPE PRODES data).
annual deforestation and the areas of remaining forests were
quantified at the basin w i d e a n d statewide scales annually.
For the spatiotemporal analysis of forest fragmentation, we
quantified the following variables: 1) the amount of forest
fragments and its size; 2) forest edge length in km and density
in km/km2, 3) areas of forest prone to edge effects or edge for-
est considering three edge penetration distances from edges and
4) the composition of edge age and the persistence of edge.
These measurements were calculated using the Interactive Data
Language (IDL, Exelis VIS).
Forest fragment size influences the degree of edge effects on
such as specie composition and its dynamics (Didham &
Lawton, 1999). We considered both natural and anthropogenic
forest fragments for quantifying the number of forest fragments
but for forest edge length, only anthropogenic forest edges are
considered in the analysis. The following ranges of forest frag-
ment sizes larger than 2 ha were considered in our analysis: <10
ha, 10 - 100 ha, 100 - 1000 ha, 1000 - 10,000 ha and >10,000
ha. Forest edge length (in km) and its annual changes were
quantified and edge density was calculated in km/km2.
Three major edge penetration distances, which each one is
related to particular types of forest disturbance, are considered
in this study: 100 m (specie composition change, forest struc-
ture and arrangement, biomass change, elevated tree mortality),
300 m (detectable large tree biomass loss, increase necro-
mass/woody debris), and 1000 m (canopy desiccation, fire sus-
ceptibility, wind turbulence, and canopy desiccation). In order
to estimate the areas of edge forests for three distances more
accurately, we downscaled the PRODES data from 90 m pixel
size into 30 m. Then an edge distance map was created by using
Euclidian distance (Figure 2). We stratified the map into the
three edge distances. The changes of forest edges created and
eroded and edge ages were tracked annually through the study
period based upon the technique used in Numata et al. (2009).
The expansion of Protected Areas between 2001 and 2010 was
also included in our analysis. We used the dataset of protected
areas in the Brazilian Amazon from the INPE PRODE website,
www.dpi.inpe.br/prodesdigical/prodes.php, the Fundação Na
Copyright © 2012 SciRes.
266
I. NUMATA, M. A. COCHRANE
Figure 2.
Deforestation and remaining forests with a range of edge penetration
distances.
cional do Índio, www.funai.gov.br., and socioambiental.org.
Results and Discussion
Forest Fragments and Edge Length
Deforestation in the 2001-2010 period has intensified forest
fragmentation by doubling the number of fragments (Table 1).
There are substantial amounts of natural forest fragments, i.e.,
those forest fragments surrounded by natural edges such as
savanna and rivers, found in some states such as Amapá, Ama-
zonas and Roraima, accounting for nearly 70% of the all forest
fragments in 2001. However, all increase of forest fragments
until 2010 is accounted for by anthropogenic forest fragments
with the substantial increases across the studied states ranging
from 85% to 130%, while the numbers of natural fragments
were declined. Most of these changes are found over the arc of
deforestation including Rondônia, Mato Grosso and Pará (Ta-
ble 1).
The increase of anthropogenic forest fragments is largely as-
sociated with the increase of small fragments (Figure 3).
The proportion of the fragments smaller than 10 ha grew by
more than 20% in the study period, occupying more than 50%
of the all fragments by 2010, meanwhile all the other fragments
in larger sizes showed some reduction in proportion. Fragment
size is vital in terms of its effects on forest ecosystems such as
specie richness of many organisms and the rate of specie loss,
and smaller fragments are affected more severely compared to
larger ones (Lovejoy et al., 1986; Ferraz et al., 2006). Further-
more, smaller fragments are often unable to support viable
populations and deleterious edge effects (Didham & Lawton,
1999). Therefore, despite the vast areas of tropical forests re-
maining in the Amazon, a large amount of forest fragments
may have been under the threat of specie loss and other edge
effects.
Annual increments of forest edge follow the annual defores-
tation (Figure 4(a)). Over the study period, 2001-2010, the
seven states of the Brazilian Amazon had additional 313,566
km of forest edge, an increase of forest edge by 36% with the
Table 1.
Changes in the amounts of forest fragments in the studied states be-
tween 2001 and 2010.
TotalNaturalHuman Total NaturalHuman
2001
2010
Acre 2705 12 2693 6,040 8 6032
Amazonas12,0908204 3886 15,576 7978 7598
Amapá1104 767 337 1613 718 895
M. Grosso16,8892815 14,074 35,777 2496 33,281
Pará 28,2645494 22,770 57,053 4843 52,210
Rondônia13,366701 12,665 23,909 645 23,264
Roraima2448 1597 851 3604 1462 2142
Figure 3.
Distribution of forest fragments in different sizes in 2001 and 2010.
average annual edge increase of 37,172 km. The average rate of
annual edge increase in the 2001-2005 period was reduced from
48,781 km/year to 25,563 km/year in the 2006-2010 due to the
drastic decline of deforestation over this period (Figure 4(b)).
All the studied states had the increase of the amount of forest
edges (Figure 5(a)). Mato Grosso had the largest increase of
edge, 46%, followed by Pará, Amazonas and Rondônia, 38%,
26% and 24%, respectively. Rondônia is the most fragmented
states with the edge density of 1.3 km/km2, followed by Mato
Grosso, Acre and Pará, while Amazonas and Amapá are the
least fragmented by human (Figure 5(b)). Overall, the edge
density over the Amazon Basin is 0.4 km/km2. Meanwhile,
many edges were destroyed due to ongoing deforestation. The
total amounts of forest edges in the central Rondônia and east-
ern Pará were decreased while the expansion of forest frag-
mentation is observed in the other places in these states.
Edge Forest
Forests prone to edge effects across the Brazilian Amazon
slightly expanded over the study period (Table 2). Of remain-
ing forests in 2010, 17% is within 1000 m of forest edge, an
increase by 3% over the 10 years, and 3% is of 100 m forest
edge only accounting for an additional 1% to the previous esti-
mate in 2001, which is equivalent to 536,138 km2. This amount
is substantially higher compared to Skole and Tucker’s 1978-
Copyright © 2012 SciRes. 267
I. NUMATA, M. A. COCHRANE
Copyright © 2012 SciRes.
268
(a)
(b)
Figure 4.
(a) Annual deforestation increments and (b) annual forest edge incre-
ments for 2001-2010.
Figure 5.
(a) Changes in the total edge length and (b) edge density for
seven states of the Legal Amazon between 2001 and 2010.
Table 2.
Edge forests with different penetration dist an ce s in 2001 and 2010.
Rem Forest (km2) 100 m (%) 300 m (%)1000 m (%)Rem Forest (km2) 100 m (%) 300 m (%) 1000 m (%)
2001 2010
Acre 139,942 3 10 25 135,397 4 12 28
Amazonas 1,460,425 1 2 6 1,452,910 1 2 8
Amapá 112,240 1 2 6 111,380 1 4 10
M. Grosso 375,110 4 13 30 324,295 7 18 38
Pará 945,202 3 8 17 889,658 4 10 21
Rondônia 148,909 7 17 35 129,960 9 21 39
Roraima 155,583 1 3 10 152,828 2 5 13
Total 3,337,411 2 6 14 3,196,428 3 7 17
1988 period analysis, 306,145 km2 for the equivalent study
region, i.e., the seven states of the Brazilian Amazon. On the
other hand, the amount of increase for 1 km edge distance for-
ests in the 1978-1988 was 201,003 km2 for the same study re-
gion, with 18,273 km2 of the average annual increase, whereas
our analysis indicates that the 1km buffer zone increased by
70,067 km2 in the past decade, 7,000 km2 of edge increment per
year.
At the state-wide scale, Rondônia and Mato Grosso have
nearly 40% of remaining forests within 1000 m of forest edge
by 2010, whereas less than 10% of remaining forests in Ama-
zonas are 1000 m from edge. In terms of individual forest
fragments, most of smaller fragments (100 ha), the edge forests
vary from 10% to 70% depending on fragment shapes and the
presence of natural edges such as rivers and savanna (Numata
et al., 2009).
Persistence of Forest Edge
In 2010, forest edges older than 10 years dominate the Ama-
zon Basin (44%), whereas those created within 5 years account
for a little bit larger than 20% (Figure 6). The edge age class
6-10yr has a larger proportion compared to 1 - 5yr for all the
states, which indicates the higher deforestation rates in the first
five years (2001-2005) compared to the 2006-2010 period
(Figures 4(a) and (b)). Overall, the amounts of newly intro-
duced edges in the 2001-2010 period are larger compared to
those created before 2001, i.e. >10 yr, except Amazonas, where
I. NUMATA, M. A. COCHRANE
0.44 0.49 0.42 0.56 0.42 0.39 0.47 0.35
0.34 0.36 0.34
0.28 0.41 0.33 0.35
0.33
0.21 0.15 0.23 0.16 0.17 0.28 0.18 0.32
Amazon ACAPAMMTPARORR
Distribution of Edge Age in 2010
>10yr 6-10yr1-5yr
Figure 6.
Distribution of edge a ge i n t he Amazon in 2010.
the old edges occupy 56% of the total edges. Many ecological
changes in forest edges occur intensively within first years after
forest fragmentation such as changes in biomass and species
composition (Laurance et al., 1997; D’Anglo et al., 2004).
More than half of edges may be undergoing the processes of
ecological and biological transitions. On the other hand, the
distribution of edges with different ages varies spatially across
the basin and within each state (Figure 7). Some old coloniza-
tion regions such as central Rondônia along the major roads and
the eastern Amazon show predominantly old edges, while ex-
tensive areas with the high amounts of young edges, 75% -
100%, indicate the active deforestation regions during the past
decade mostly identified across the arc of deforestation but
more concentrated in western Rondônia and northwestern Mato
Grosso, and the regions along the new highway in Pará. This
spatial pattern of forest edges with different ages indicates the
shift of deforestation frontier and intensity of ecological
changes associated with edge effects.
The persistence of edge varied between the first (2001-2005)
and second half (2006-2010) of the study period (Figure 8).
During the first five years after edge creation, the forest edges
created in 2001 were reduced by 38%, staying a shorter time in
landscapes compared to those edges formed in 2005 which
presents the reduction of edges by 25% in five years. This
represents two different time periods at high and low rates of
deforestation. Varying edge persistence in landscapes may have
important implications for ecosystems. Numata et al. (2011)
estimated that the amount of carbon emissions of biomass col-
lapse in forest edges to all deforestation driven carbon in the
Amazon was 1.7% - 3.0% in the 2001-2005 period, however
this amount increased to 3.3% - 5.6% in the 2006-2010, longer
edge exposure period compared to the first, which demonstrates
the effects of persistence of edges on regional carbon fluxes.
The exposure of forest edges for longer periods may increase
the risk of large scale edge effects in remaining forests as well
as synergistic interactions with fires and climate change (Coch-
rane & Laurance et al., 2008). On the other hand, proliferating
vines and branch growth as edges age, may buffer edge inten-
sity (Laurance et al., 2011).
Protected Areas and Forest Fragmentation
Protected areas expanded more than 100% since 2001 in the
Brazilian Amazon (Table 3) and the proportion of remaining
forests under protection of different categories, ie., strictly pro-
tected, sustainable use and indigenes land, grew from 23.5% in
2001 to 51% in 2010 in our study region due to their expansion
per se combined with the reduction of forest areas by defore-
Figure 7.
Spatially explicit map of edge age of the year 2010.
Remaining edge (%)
Year after edge creation
Figure 8.
Edge decay rates of forest edges created in 2001 and 2005 during five
years after edge creation.
station over the past 10 years. This has certainly affected forest
fragmentation of the Amazon.
Although nearly 80% of tropical forests still remain in the
Brazilian Amazon (INPE 2012), less than half of this amount
can be explored by human if the environmental regulations set
by the Brazilian Government do not get violated. If we consider
forest edge density of remaining forests outside of protected
areas in the Amazon basin only, it would increase from 0.40
km/km2 to 0.80 km/km2 as of 2010. In the case of Rondônia,
the most fragmented state, it would have its edge density from
1.26 to 3.11 km/km2. Furthermore, 34% of remaining forests
outside the protected areas in the basin would be within 1km of
edges, whereas 95% of unprotected forests in Rondônia is
within 1km of edge. These results indicate that there are two
contrasting landscapes across the Amazon. While nearly half of
remaining forests will be undisturbed under protected areas,
another part would be highly fragmented and disturbed land-
scapes. If deforestati o n c o n t i n u e s only in remaining unprotected
forests, the process of fragmentation occurs in smaller forest
fragments, which increase edge erosion and the amount of for-
est edge will eventually begin to decline as remaining forests
keep shrinking.
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I. NUMATA, M. A. COCHRANE
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270
Table 3.
Changes of remaining forests (RF) and protected a r e a s (PA) bet ween 200 1 and 2010 for seven states of t he Brazilian Amazon.
RF (km2) PA (km2) PA/RF (%) RF (km2) PA (km2) PA/RF (%)
2001 2010
Acre 139,942 42,590 30.4 135,397 78,017 57.6
Amazonas 1,460,425 261,522 17.9 1,452,910 679,598 46.8
Amapá 112,240 19,131 17.0 111,380 58,593 52.6
M. Grosso 375,110 86,301 23.0 324,295 114,224 35.2
Pará 945,202 229,541 24.3 889,658 537,255 60.4
Rondônia 148,909 69,780 46.9 129,960 77,418 59.6
Roraima 155,583 36,828 23.7 152,828 85,058 55.7
Total 3,337,411 745,694 22.3 3,196,428 1630,163 51.0
The expansion of protected areas and the law enforcement
efforts led by the Government of Brazil have been an important
factor of reducing deforestation over the past years (Nepstad et
al., 2009; Barreto & Silva, 2010; Soares et al., 2010). Effec-
tiveness of the majority of Amazonian protected areas has been
considered high, avoiding vast area of deforestation and mini-
mizing carbon emissions and possible impacts of climate
change on forest (Walker et al., 2009; Soares et al., 2010). Until
2010, only 1.5% of Amazonian protected areas have been de-
forested (INPE, 2012). Even in unprotected areas, deforestation
has been reduced dramatically since 2006 and a lot of clear
cutting has occurred in areas smaller than 25 ha (Escada et al.,
2011). If this situation continues, regional edge effects will be
reduced as forest edges remain longer in landscapes and most
forest fragments will reach new equilibrium in the ecosystems
(Laurance et al., 2011).
Conclusion
We performed spatial and temporal analysis of forest frag-
mentation in the Brazilian Amazon over the 2001-2010 period.
Our results indicate that intensive forest fragmentation has oc-
curred in the past decade, doubling the number of forest frag-
ments predominantly with small fragments (<100 ha), intro-
ducing new forest edges (<10 years old) accounting for 55% of
total forest edges as of 2010. In unprotected forests, 34% is
within 1 km of forest edge. Forest degradation has been accel-
erated with larger scale edge effects and vulnerability of frag-
mented forest ecosystems to synergistic interactions between
fires, forest fragmentation and climate change may potentially
increase. Conversely, the expansion of protected areas and the
law enforcement have played very important roles in reducing
deforestation and forest fragmentation over the past years. The
protected areas in the Amazon grew more than 100% over the
past decades and most of forest fragmentation has occurred out
of the protected areas. The degree of forest fragmentation such
as the increment of new forest edges varied according to the
annual deforestation rates. Intensive forest fragmentation was
found in 2001-2005 when the deforestation rates were high,
however an opposite situation was found in the 2006-2010
period when deforestation rates dropped dramatically. As Brazil
has committed to reducing deforestation rate by 80% compared
to the average rate of deforestation between 1995 and 2005
until 2020 (Nepstad et al., 2009), forest fragmentation will slow
down and regional edge effects on remaining forest will be
reduced as forest edges remain longer and reach in new eco-
logical equilibrium in landscapes unless Brazilian environ-
mental policies change as it has been discussed the reform to
Forest Code, that may allow landowners further forest clearing.
Acknowledgements
This work was supported by the Biological Diversity Pro-
gram of the Earth Science Division of the NASA Science Mis-
sion Directorate (NNX07AF16G). We also thank Luis Maurano,
Marisa Motta and Maria Isabel from INPE for their helps and
comments on the digital PRODES data.
REFERENCES
Archard, F., Eva, H. D., Mayaux, P., Stibig, H. J., & Belward, A.
(2004). Improved estimates of net carbon emissions from land cover
change in the tropics for the 1990s. Global Biogeochemical Cycles,
18, GB2008.
Arima, E. Y., Walker, R. T., Sales, M., Souza, C., & Perz, S. G. (2008).
The fragmentation of space in the Amazon basin: Emergent road
networks. Photogrammetric Engineering & Remote Sensing, 74, 699-
709.
Asner, G. P., Knapp, D. E., Broadbent, E. N., Oliveira, P. J. C., Keller,
M., & Silva, J. N. (2005). Selective logging in the Brazilian Amazon.
Science, 310, 480-482. doi:10.1126/science.1118051
Baccini, A., Goetz, S. J., Walke r, W. S., Laporte, N. T. , Sun, M., Sulla-
Menashe, D. et al. (2012). Estimated carbon dioxide emissions from
tropical deforestation improved by carbon-density maps. Nature
Climate Change, 2, 182-185. doi:10.1038/nclimate1354
Barona, E., Ramankutty, N., Hyman, G., & Coomes, O. T. (2010). The
role of pasture and soybean in deforestation of the Brazilian Amazon.
Environmental Research Letters, 5, 024002.
doi:10.1088/1748-9326/5/2/024002
Barreto, P., & Silva, D. (2010). Will cattle ranching continue to drive
deforestation in the Brazilian Amazon? Proceedings from the Inter-
national Conference: Environment and Nautral Resources Manage-
ment in Developing and Transition Economics, Clemont Ferrand,
18-19 November 2010.
Briant, G., Gond, V., & Laurance, S. G. (2010), Habitat fragmentation
and the desiccation of forest canopies: A case study from eastern
Amazonia. Biological C on s e rv a t io n , 143, 2763-2769.
doi:10.1016/j.biocon.2010.07.024
Broadbent, E. N., Asn er, G. P., Kelle r, M., Knapp, D. E ., Oliveira, P. J.
C., & Silva, J. N. (2008). Forest fragmentation and edge effects from
I. NUMATA, M. A. COCHRANE
deforestation and selective logging in the Brazilian Amazon. Bio-
logical Conservation, 141, 1745-1757.
doi:10.1016/j.biocon.2008.04.024
Cochrane, M. A. (2001). Synergistic interactions between habitat frag-
mentation and fire in evergreen tropical forests. Conservation Biol-
ogy, 15, 1515-1521. doi:10.1046/j.1523-1739.2001.01091.x
Cochrane, M. A. (2003). Fire science for rainforests. Nature, 421, 913-
919. doi:10.1038/nature01437
Cochrane, M. A., & Laurance, W. F. (2002). Fire as a large-scale edge
effect in Amazonian forests. Journal of Tropical Ecology, 18, 311-
325. doi:10.1017/S0266467402002237
Cochrane, M. A., & Laurance, W. F. (2008). Synergisms among fire,
land use, and climate change in the Amazon. Ambio, 37, 522-527.
doi:10.1579/0044-7447-37.7.522
Coe, M. T., Costa, M. H., & Soares-Filho, B. S. (2009). The influence
of historical and potential future deforestation on the stream flow of
the Amazon river-land surface processes and atmospheric feedbacks.
Journal of Hydrology, 369, 165-174.
doi:10.1016/j.jhydrol.2009.02.043
D’Angelo, S. A., Andrade, A. C. S., Laurance, S. G., Laurance, W. F.,
& Mesquita, R. C. G. (2004). Inferred causes of tree mortality in
fragmented and intact Amazonian forests. Journal of Tropical Ecol-
ogy, 20, 243-246. doi:10.1017/S0266467403001032
DeFries, R. S., Houghton, R. A., Hansen, M. C., Field, C. B., Skole, D.,
& Townshend, J. (2002). Carbon emissions from tropical deforesta-
tion and regrowth based on satellite observations for the 1980s and
1990s. Proceedings of the National Academy of Sciences of the
United States of America, 99, 14256-14261.
doi:10.1073/pnas.182560099
Didham, R. K., & Lawton, J. H. (1999). Edge structure determines the
magnitude of changes in microclimate and vegetation structure in
tropical forest fragments. Biotropica, 31, 17-30.
Escada, M. I. S., Maurano, L. E., Rennó, C. D., Amaral, S., & Valeri-
ano, D. M. (2011). Avaliação de dados dos sistemas de alerta da
Amazonia: DETER e SAD. In XV simpósio brasilieiro de sensoria-
mento remoto, Curitiba, 30 April-5 May 2011.
Fahrig, L. (2003). Effects of habitat fragmentation on biodiversity.
Annual Review of Ecology Evolution and Systematics, 34, 487-515.
doi:10.1146/annurev.ecolsys.34.011802.132419
Ferraz, S. F. D., Capao, L., & Vettorazzi, C. A. (2006). Temporal scale
and spatial resolution effects on Amazon forest fragmentation as-
sessment in Rondônia. International Journal of Remote Sensing, 27,
459-472. doi:10.1080/01431160500259907
Gardner, T. A., Barlow, J., Chazdon, R., Ewers, R., Harvey, C. A.,
Peres, C. A., & Sodhi., N. S. (2009). Prospects for tropical forest bio-
diversity in a human-modified world. Ecology Letters, 12, 561- 582.
doi:10.1111/j.1461-0248.2009.01294.x
Hansen, M. C., Stehman, S. V., Potapov, P. V., Loveland, T. R., Town-
shend, J. R. G., DeFries, R. S. et al. (2008). Humid tropical forest
clearing from 2000 to 2005 quantified by using multitemporal and
multiresolution remotely sensed data. Proceedings of the National
Academy of Sciences of the United States of America, 105, 9439-
9444. doi:10.1073/pnas.0804042105
INPE (2012). PRODES—Desflorestamento nos municipios. São José
dos Campos: Instituto National de Pesquisas Espaciais.
Kapos, V. (1989). Effects of isolation on the water status of forest
patches in the Brazilian Amazon. Journal of Tropical Ecology, 5,
173-185. doi:10.1017/S0266467400003448
Laurance, W. F., Camargo, J. L. C., Luizao, R. C. C., Laurance, S. G.,
Pimm, S. L., Bruna, E. M. et al. (2011). The fate of Amazonian for-
est fragments: A 32-year investigation. Biological Conservation, 144,
56-67. doi:10.1016/j.biocon.2010.09.021
Laurance, W., Coc hrane, M ., Be rgen, S., F earns ide, P . M., Dela monica,
P., Barber, C., D’Angelo, S., & Fernandes, T. (2001). The future of
the Brazilian Amazon. Science, 291, 438-439.
doi:10.1126/science.291.5503.438
Laurance, W., Laurance, S., & Delamonica, P. (1998). Tropical forest
fragmentation and greenhouse gas emissions. Forest Ecology and
Management, 110, 173-180. doi:10.1016/S0378-1127(98)00291-6
Laurance, W. F., Laurance, S. G. , Ferreira, L. V., de Merona, J. M. R. ,
Gascon, C., & Lovejoy, T. E. (1997). Biomass collapse in Amazo-
nian forest fragments. Science, 278, 1117-1118.
doi:10.1126/science.278.5340.1117
Laurance, W. F., Nascimento, H. E. M., Laurance, S. G., Andrade, A.,
Ribeiro, J. E. S. J., Giraldo, J. P. et al. (2007). Rapid decay of
tree-community composition in Amazonian forest fragments. Pro-
ceedings of the National Academy of Sciences of the United States of
America, 103, 19010- 19014. doi:10.1073/pnas.0609048103
Lovejoy, T. E., Bierregaard, R. O., Rylands, A. B., Malcolm, J. R.,
Quintela, C. E., Harper, L. H. et al. (1986). Edge and other effects of
isolation on Amazon forest fragments. Conservation Biology. The
science of Scarcity and Diversity, 257-285.
Morton, D. C., DeFries, R. S., Shimabukuro, Y. E., Anderson, L. O.,
Arai, E., Espirito-Santo, F. D., Freitas, R., & Morisette, J. (2006).
Cropland expansion changes deforestation dynamics in the southern
Brazilian Amazon. Proceedings of the National Academy of Sciences
of the United States of America, 103, 1463 7-14641.
doi:10.1073/pnas.0606377103
Nascimento, H. E. M, & Laurance, W. F. (2004). Biomass dynamics in
Amazonian forest fragments. Ecological Applications, 14, S127-
S138. doi:10.1890/01-6003
Nepstad, D., Soares, B. S., Merry, F., Lima, A., Moutinho, P., Carter, J.,
et al. (2009). The end of deforestation in the Brazilian Amazon. Sci-
ence, 326, 1350-1351. doi:10.1126/science.1182108
Nepstad, D. C., Stickler, C. M., & Almeida, O. T. (2006). Globalization
of the Amazon soy and beef industries: Opportunities for conserva-
tion. Conservation Biology, 20, 1595-1603.
doi:10.1111/j.1523-1739.2006.00510.x
Numata, I., Cochrane, M. A., Roberts, D. A., & Soares, J. V. (2009).
Determining dynamics of spatial and temporal structures of forest
edges in south western Amazonia. Forest Ecology and Management,
258, 2547-2555. doi:10.1016/j.foreco.2009.09.011
Numata, I., Cochrane, M. A., Souza, C. M., & Sales, M. H. (2011).
Carbon emissions from deforestation and forest fragmentation in the
Brazilian Amazon. Environmenta l Research Letters, 6, 004003.
doi:10.1088/1748-9326/6/4/044003
Phillips, O. L., Rose, S., Mendoza, A. M., & Vargas, P. N. (2006).
Resilience of southwestern Amazon forests to anthropogenic edge
effects. Conservation Biology, 20, 1698-1710.
doi:10.1111/j.1523-1739.2006.00523.x
Skole, D., & Tucker, C. (1993). Tropical deforestation and habitat frag-
mentation in the Amazon—Satellite data from 1978 to 1988. Science,
260, 1905-191. doi:10.1126/science.260.5116.1905
Soares, B., Moutinho, P., Nepstad, D., Anderson, A., Rodrigues, H.,
Garcia, R. et al. (2010), Role of Brazilian Amazon protected areas in
climate change mitigation. Proceedings of the National Academy of
Sciences of the United States of America, 107, 10821-10826.
doi:10.1073/pnas.0913048107
Walker, R., Moore, N. J., Arima, E., Perz, S., Si mmons, C., Cald as, M .,
Vergara, D., & Bohrer, C. (2009). Protecting the Amazon with pro-
tected areas. Proceedings of the National Academy of Sciences of the
United States of America, 106, 10582-10586.
doi:10.1073/pnas.0806059106
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