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TRANSCRIPT
ORI GIN AL PA PER
Examining complexities of forest cover changeduring armed conflict on Nicaragua’s Atlantic Coast
Kara Stevens • Lindsay Campbell • Gerald Urquhart • Dan Kramer •
Jiaguo Qi
Received: 2 February 2011 / Accepted: 15 June 2011� Springer Science+Business Media B.V. 2011
Abstract The effects of armed conflict on biodiversity are an emerging concern in
conservation due in part to the occurrence of war in biodiversity hotspots, though few
studies have addressed it. We investigate this topic by examining changes in forest cover
on the Atlantic Coast of Nicaragua from 1978 to 1993, a period covering their civil war.
We predict an increase in forest cover between pre- and post-conflict periods as residents
abandoned agriculture plots and migrated from conflict areas. We used a remote sensing
approach to detect changes in forest cover area and fragmentation at two study sites.
Results confirmed that in the first 5–7 years of the conflict, reforestation was greater than
deforestation, but in the latter years of the conflict deforested land almost doubled that
which was reforested. Although some forest loss was due to Category 4 Hurricane Joan,
several conflict-related factors were partially responsible for these results, such as mass
human migration and land reform. Understanding how and why forest cover changes
during periods of conflict can help conservationists protect resources both during war and
in the tumultuous period following the cessation of violence when nascent governments
lack the power to effectively govern and community institutions are fractured by war. In
areas where the livelihoods of people are directly dependent on local resources, antic-
ipating ecological and social impacts can help improve future conservation efforts.
Keywords Conflict � Deforestation � Land-cover change � Nicaragua � War
K. Stevens (&) � G. Urquhart � D. KramerDepartment of Fisheries and Wildlife, Michigan State University, 13 Natural Resources,East Lansing, MI 48828, USAe-mail: [email protected]
L. Campbell � J. QiCenter for Global Change and Earth Observation, Michigan State University, East Lansing, MI, USA
G. UrquhartLyman Briggs College, Michigan State University, East Lansing, MI, USA
D. KramerJames Madison College, Michigan State University, East Lansing, MI, USA
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Biodivers ConservDOI 10.1007/s10531-011-0093-1
AbbreviationsAI Aggregation index
CA Class area
FSLN Sandinista National Liberation Front
MSS Multispectral scanner
NIR Near infra-red
R.A.A.N. Northern Atlantic Autonomous Region
R.A.A.S. Southern Atlantic Autonomous Region
RMS Root mean square
TM Thematic mapper
UTM Universal transverse mercator
Introduction
Natural resources and armed conflict are intricately linked, with resource scarcity or
competition cited as a causative agent of conflict (Johannesson 2004; Ross 2004) or natural
resources destroyed during conflict either inadvertently as a side effect of war or delib-
erately to destroy enemy territory and affect local livelihoods (Lamb 1985; United Nations
Environment Program 2007). In addition, increased exploitation of resources can occur
immediately following conflict as weakened governments and communities transition to
peace but lack stability or power to effectively manage and prevent exploitation. Resources
can be used as a tool for peacebuilding and fostering cooperation (Le Billon 2000; Hatton
et al. 2001; Conca and Wallace 2009). Despite the links, few studies have examined
empirically the effects of war on the environment. Understanding the direct and indirect
impacts of armed conflict on biodiversity was highlighted as one of the top 100 questions
of importance to the conservation of global biodiversity (Sutherland et al. 2009). The links
between conflict and deforestation are particularly important—conflict may facilitate or
prevent industrial and subsistence use of forests, such as logging or agriculture, and the
resulting impact has important implications for post-conflict restoration and rehabilitation
of both social and ecological systems.
To address the larger topic of the relationship between conservation and conflict, this
study investigates changes in forest cover on the Atlantic Coast of Nicaragua during its
civil war, in which 30,000 Nicaraguans died and hundreds of thousands of Nicaraguan
citizens were displaced in the 1980s (Prevost 1987; Sollis 1989). As with many conflicts
throughout the past century, this one took place in an area of rich biodiversity (Hanson
et al. 2009). Nicaragua’s Atlantic Coast hosts one of the largest remaining tracts of
lowland tropical rainforest in Mesoamerica, which holds populations of five globally
threatened large mammal species (International Union for Conservation of Nature 2011)
and along with one of the most productive fisheries of the Caribbean Sea, supports the
livelihood of the unique indigenous cultures of the semi-autonomous Atlantic Coast. The
armed conflict between the Sandinista National Liberation Front (FSLN) and Contra rebel
groups directly involved or indirectly affected rural areas of eastern Nicaragua from 1979
to 1990.
Nicaragua’s leadership from the 1970s to the 1990s had markedly different approaches
to land use and the environment. A lack of environmental policy characterized the Somoza
family rule from 1937 to 1979, a time when exploitation for economic benefit was the
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norm, and foreign firms exploited the country’s natural resources for the economic benefit
of the political leadership (Rice 1989; Sollis 1989; Vilas 1989). The Sandinista takeover in
1979 sought to nationalize and redistribute land from large landowners to the landless and
smallholders. By 1985, they had succeeded in seizing 1.8 million ha of land, two-thirds of
which was on the Atlantic Coast (Wearne 2002). The Contra War prevented lumber
operations from building access roads to prized timber, thus preventing land use change
typically found along road arteries (Vandermeer 1991). Neither fighting faction inten-
tionally destroyed Nicaragua’s vast tracts of tropical forest on the Atlantic Coast during the
war (Vandermeer 1991). Forced conscription, a depressed economic system, and conflict
between rebel groups and the Sandinista army pushed people from remote rural regions to
city centers for safety, and tens of thousands eventually fled across Nicaragua’s borders to
Honduras and Costa Rica (Basok 1990; Christie et al. 2000). From 1981 to 1989, the major
cities along the Atlantic Coast, including Bluefields, Puerto Cabezas and Siuna, doubled in
population (Sollis 1989). This migration, coupled with the decline in commercial timber
exploitation may have resulted in no reduction in forest cover throughout the period of the
war, and perhaps some forest regrowth in fields left fallow.
Previous work has been mixed on the environmental effects of Nicaragua’s civil war.
Some reports suggest that wildlife and fish populations rebounded during the war due to a
lack of economic growth or exploitation during the conflict (Nietschmann 1990). Hundreds
of thousands of people were displaced in the twelve-year period, and as agricultural fields
and pastures were abandoned, forest regrowth is believed to have taken place (Nietsch-
mann 1990). Others suggest the environment was another victim of the war (Heiner et al.
1989). Reports provide differing accounts of the extent of agriculture and extraction that
occurred and how it affected forest cover, and none have used quantitative methods to
describe the change.
Quantitative assessments of forest fragmentation during periods of conflict coupled with
potential economic and social drivers are a topic scarcely covered in the literature. Periods
of conflict can further deplete or restore forested regions depending on the characteristics,
location and duration of the conflict. Two published studies used a remote sensing
approach to examine the effects of conflict on land cover change, but primarily focused on
changes in agricultural land (Suthakar and Bui 2008; Witmer and O’Loughlin 2009).
Although several studies have demonstrated the capacity to quantify forest cover change
using multitemporal satellite imagery in tropical regions (Skole and Tucker 1993; Moran
et al. 1994; Mertens and Lambin 1997; Geoghegan et al. 2001), to our knowledge, this is
the first study in the literature using a remote sensing approach to examine forest cover
change during a period of conflict (Suthakar and Bui 2008; Witmer and O’Loughlin 2009).
We hypothesize the following changes in forest cover over the period of the civil war in
Nicaragua:
(1) An increase in forest cover along the Atlantic Coast during the armed conflict
compared to pre-conflict forest cover extents due to abandonment of rural areas and
reduction in agricultural expansion as a result of the conflict;
(2) An increase in forest fragmentation, exhibited by more numerous forest patches
between pre- and post-conflict time periods within the study sites based on areas of
settlement. Areas of settlement are found along the eastern coast of the southern site
and along a major roadway in the northern site.
The objective of this study is to quantify forest cover change over the period of
Nicaragua’s civil war and to better understand interactions between conflict, local
communities and the natural environment.
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Study site
Two sites with a total area of approximately 160,000 ha were selected for analysis based
on our ability to locate forested areas with relatively cloud-free satellite imagery along
Nicaragua’s Atlantic Coast for three time periods, during similar phenological stages, set at
5 year minimum intervals between 1978 and 1993 (Fig. 1; Table 1). We based minimum
temporal periods on previous studies that determined that a 5-year interval was sufficient
for establishment of pioneer species after disturbance from hurricane or agricultural
abandonment (Uhl and Jordan 1984; Boucher et al. 2001; Guariguata and Ostertag 2001).
The sites host two types of forest ecoregions: Central American Atlantic moist forest and
Meso-American Gulf Caribbean mangroves (Olson et al. 2001). Atlantic moist forests
predominate along the Atlantic Coast. Common species include Dipteryx panamensis,
Cordia alliodora, Cecropia obtusifolia, Galipea granulosa, Dendropanax arboreus, Mi-conia spp., Pentaclethra macroloba, Qualea spp., Ceiba pentandra and Ficus spp. (Taylor
1963; Christie et al. 2000). Mangrove forests reside at the confluence of the terrestrial and
aquatic ecosystems of Pearl Lagoon and much of the Atlantic Coast. Species include red
(Rhizophora mangle), white (Languncularia racemosa), and black (Avicennia germinans)
mangrove as well as buttonwood mangrove (Conocarpus erectus) (Roth 1992).
The Atlantic Coast has the lowest population density in Nicaragua, estimated at 4
people/km2 in 1989 (Campbell and Hammond 1989). The main ethnic groups depending
upon these forests for their livelihoods are the Rama, Miskitu, Sumu, Garifuna, Creole and
Fig. 1 Study areas from the R.A.A.S. and R.A.A.N. provinces of Nicaragua
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Mestizo people, who practice subsistence fishing and farming in the autonomous regions
that comprise the northern [Region Autonoma del Atlantico Norte (Northern Atlantic
Autonomous Region) or R.A.A.N.] and southern [Region Autonoma del Atlantico Sur
(Southern Atlantic Autonomous Region) or R.A.A.S.] provinces of the Atlantic Coast. The
Mestizo population in this area immigrated from the western region of the country and has
different patterns of resource use and political affiliations compared to indigenous popu-
lations in the rest of the study area. The site in the R.A.A.N. will be referred to as the
northern site, and the site in the R.A.A.S. as the southern site, hereafter.
Methods
This study used post-classification change detection methods to quantify conversion from
forest to non-forest or from non-forest to forest based on multitemporal satellite images.
We generated a ‘‘from–to’’ matrix to quantify trends from the change detection analyses,
and these temporal trends were then analyzed in conjunction with previously reported data
on land tenure, human migration and funding for the conflict to explain potential causes of
forest change.
Landsat satellite images with a universal transverse mercator (UTM) Zone 17N pro-
jection were obtained from three different time periods (Table 1). We acquired Landsat 3
multispectral scanner (MSS) images with a 60 m resolution for the southern site and we
geometrically corrected the 1978 and 1992 images to the 1985 image with root mean square
(RMS) values\0.5 pixels (Bannari et al. 1995). We acquired Landsat 5 MSS and thematic
mapper (TM) images for the northern site and resampled the 1978 MSS image to a 30 m
resolution before geometrically correcting it to the 1988 and 1993 TM images with an
RMS \ 0.05 pixels. Resampling did not improve the MSS image resolution, but provided
consistency in pixel size comparison across time intervals. We atmospherically corrected all
images from both sites using a CosT atmospheric correction model (Chavez 1996).
We selected regions experiencing minimal cloud cover in the satellite imagery across all
time periods. We partitioned images into individual classes based on variations in spectral
signatures using an ISODATA unsupervised classification method (Lillesand et al. 2004).
Parameters were set on the principal axis with two standard deviations, approximate true
color, and 10 iterations or 95% convergence.
Anderson’s Level I classification scheme acted as a framework from which to divide the
initial classes into specific land cover categories (Anderson et al. 1976). Pixels classified as
Table 1 Selected satellite imag-ery for land cover changeanalysis
Satellite Resolution(m)
WRS path/row
Date
Southern study site
Landsat MSS 60 p16r51 1 April 1978
Landsat MSS 60 p16r51 8 April 1985
Landsat MSS 60 p16r51 5 May 1992
Northern study site
Landsat MSS 60 p16r50 1 April 1978
Landsat TM 30 p15r50 8 April 1988
Landsat TM 30 p15r50 9 February 1993
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forest included deciduous, mixed forested land, and secondary forest. Pixels classified as
non-forest included those identified as agriculture, rangeland, and barren land. Urban and
built-up land were not present in this study area, and we used a mask to eliminate other
non-relevant categories (water, wetland, cloud, or cloud shadow). Execution of a 3 9 3
statistical majority filter across each image eliminated classification noise (Mather 2004).
Output images contained only forest and non-forest pixels that were never classified as
water, wetland, cloud, or cloud shadow to ensure an equal area comparison across all time
periods.
Our ability to accurately associate land cover types to spectral signatures was limited
due to a lack of ground truth data from historical time periods. Therefore, we relied on
visual interpretation to determine appropriate land cover types (Martin and Howarth 1989;
Skole and Tucker 1993; Mas and Ramirez 1996). Reduced land cover categories (forest,
non-forest) made class differentiation using visual interpretation relatively straightforward
and fairly accurate, although differentiation between land cover categories with similar
spectral signatures is a common challenge when working with multi-spectral imagery. For
example, distinguishing primary from secondary forest or grassland from shrubland,
agriculture, or savanna proves challenging when training data does not exist. In this study,
we created a forest class that included both primary and secondary forest to eliminate
spectral confusion. Therefore, we needed only to distinguish these two classes from
alternative, non-forest land cover types. While still a formidable task, one advantage was
that forest regeneration in tropical regions saturates the near infra-red (NIR) band in multi-
spectral imagery quickly due to the presence of dense, green biomass, and this phenom-
enon is most prominent during dry season months when crop foliage is least dense, pro-
viding a tool to differentiate secondary forest from non-forest categories (Steininger 1996).
Despite class aggregation, the advantage of high NIR reflectance during forest regeneration
stages, and image acquisition during dry season months, classification uncertainty
remained with misclassification potential existing between young pioneer tree saplings and
shrubs, forbs or grasses.
Because ground truth data for each time period and region did not exist, we generated
50 points each located within classified forest and non-forest pixels from each image using
a stratified random sampling approach (Jensen 1996). Points located at the perimeter
between classes or No Data values were not included in the accuracy assessment because
of 3 9 3 filter effects in these regions. The random points were reclassified and then
compared to the existing classification. Producer’s accuracy values ranged from 84.31 to
95.65% across forest and non-forest classes in the southern site, while user’s accuracy
values ranged from 84 to 96%. The overall Kappa coefficient values ranged from 0.71 to
0.84. The northern site exhibited producer’s accuracy values ranging from 81.36 to
95.12%, user’s accuracy values ranging from 78 to 96%, and overall Kappa coefficient
values ranging from 0.69 to 0.90.
Change detection
Forest and non-forest pixel areas were measured for each time period in each site and older
values were subtracted from newer values to quantify change. Pixel values equal to zero
corresponded to no change from either forest or non-forest classes; pixel values equal to 1
indicated a change from non-forest to forest; and pixel values equal to -1 indicated a
change from forest to non-forest between two time periods. We calculated the deforestation
rate using Eq. 1.
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R ¼ 1=ðt2 � t1ÞðlnðA2 � A1ÞÞ ð1Þ
where R is the deforestation rate and A1 and A2 are the amount of forested area at time 1
and time 2, respectively (Puyravaud 2003).
Fragmentation
We divided each study site by a north–south or east–west demarcation based on spatial
variation in land use between areas of indigenous/Afro-Caribbean settlement and relatively
remote regions before conducting a fragmentation analysis (Fig. 1). In the southern site,
communities reside along the lagoon edge with relatively remote areas located beyond
10 km from the lagoon edge. The remote area of the northern site began 5 km south of the
roadway. We created subsets in order to make a targeted analysis of changes within regions
likely abandoned or untouched during the conflict and changes within regions where
people concentrated. The purpose was to compare variation over time periods and not
between different regions.
We calculated three landscape metrics to characterize and to quantify forest fragmen-
tation in each area between time periods. We quantified class area (CA), number of patches
(NP), and aggregation index (AI) values using an 8-neighbor rule (Gergel and Turner 2002;
McGarigal et al. 2002). CA summed the total forest CA and the total non-forest CA and
converted the units into hectares (McGarigal et al. 2002). Number of patches calculated the
number of forest and non-forest land cover patches in each site in each time period
(McGarigal et al. 2002). No background or border cells were included in the calculation,
and patch attributes characterizing shape or size were not described in this metric.
The AI is a class-specific measurement that derives land cover aggregation values based
on shared cell edges within a raster grid. AI is the ratio of the number of shared grid cell
edges from a particular class versus the maximum possible number of shared grid cell
edges from that class (He et al. 2000). Values increase from 0 to 1.0 as aggregation
increases (Eq. 2).
AI ¼ gii
max! gii
� �100ð Þ ð2Þ
gii is the number of like adjacencies between pixels of patch type i and max ? gii is equal
to the maximum number of like adjacencies between pixels of patch type i (McGarigal
et al. 2002). This metric ignored boundary edges and used a single-count method. Metric
values from older images were subtracted from newer images to identify changes in forest
fragmentation across time periods.
Results
Change detection
Thirteen percent (13%) of the total study area was deforested between pre-conflict (1978)
and post-conflict (1992/1993). Approximately 10% of the landscape changed from non-
forest to forest cover, and over 75% showed no change. The northern and southern sites
showed a similar trend in that the area of land deforested from the mid-1980s to the end of
the conflict was much higher than in the previous 7–10 years (Table 2). The time period
from 1978 to 1985/1988 will be referred to as the first interval, and the time period from
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1985/1988 to 1992/1993 will be referred to as the second interval, hereafter. The Mestizo
settlement of Pueblo Nuevo in the northwest corner of the southern site experienced
deforestation during the first interval, while reforestation occurred during the second
interval (Fig. 2).
Fragmentation analysis
Settled areas of both sites accounted for numerous patches of deforestation during the
second interval (Table 3; Figs. 2, 3). Remote areas also increased in number of patches
across all time periods. Settled regions of both sites increased in forest cover during the
first interval, but lost forest cover in the second interval, resulting in little net change
between pre- and post-conflict. The remote area of the northern site increased in forest
cover by 0.1% between pre- and post-conflict periods, while the remote area of the
southern site declined by 20%. The total number of patches increased in remote and settled
regions of both sites between pre- and post-conflict, although the number of patches
decreased in the migrant-settled region, with 22% fewer forest patches in 1992 than in
1978. The entire southern site, including the migrant-settled area, decreased in net
aggregation between 1978 and 1992, while the northern site increased in overall
aggregation.
Discussion
Our hypothesis that more reforestation than deforestation occurred between the pre- and
post-conflict periods was accurate for the 160,000 ha area analyzed for this study for the
first interval. Results from the second interval, an increase in deforestation in both study
sites, indicated the complexities of forest cover change during conflict. We also hypoth-
esized an increase in forest fragmentation in settled areas between pre-and post conflict
periods as measured by number of patches and the AI. In fact, both settled and remote areas
increased in fragmentation over the conflict period, and trends between study sites over the
two time intervals demonstrated a lack of uniformity in land-cover change. Several factors
may have contributed to these results, including Hurricane Joan, human migration, land
reform, and the date used as ‘‘post-conflict’’ for the purposes of this analysis. These factors
and the significance of the results will be discussed here.
Table 2 Forest cover change from 1978 to 1993 on Nicaragua’s Atlantic Coast
Reforestation(%)
Deforestation(%)
Nochange(%)
Net change inforest coverper annum (ha)
Deforestationrate (%)
Southern site
1978–1985 10.8 7.8 81.4 221.9 0.52
1985–1992 6.8 17.8 75.4 -795.9 -1.94
1978–1992 9.1 16.9 74.0 -287.1 -0.72
Northern site
1978–1988 12.4 8.7 78.9 401.4 0.44
1988–1993 7.1 12.0 80.9 -1,098 -1.20
1978–1993 10.1 11.4 78.6 -98.4 -0.11
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A net increase in forest cover in the northern and southern sites in the first interval
support our hypothesis that forest regeneration occurred during the time period that the
conflict intensified as determined by US Congressional funding and refugee movement
(Fig. 4). The United States Congress was the main funding source for the Contra rebel
group and as such, their support, as well as the mass emigration of Nicaraguan refugees,
serves as a proxy for the escalation of the conflict. The number of Nicaraguan refugees
peaked in 1989 two years after a peak in U.S. funding for Contra rebels that included $70
Fig. 2 Forest cover change in southern site: a from 1978 to 1985, b 1985–1992 and c 1978–1992
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million USD in military aid (Sobel 1995; The UN Refugee Agency 2011). Total forest
cover was highest when the conflict was most intense and decreased as the number of
refugees declined and U.S. funding tapered. Both sites experienced a \1% increase in
forested areas during the first interval, which supports previous research findings that
timber and fuel wood extraction were interrupted substantially.
Another potential cause of increased deforestation in the last years of the conflict may
relate to the dates we used as post-conflict for this analysis. Post-conflict is a nebulous
term. By varying accounts, the war ended or de-escalated between 1988 and 1990
(Table 4). We used 1992 (southern site) and 1993 (northern site) as post-conflict, because
Table 3 Analysis of change in fragmentation
Site Total number offorest patches
Total forest area (ha) Forestarea
Number offorestpatches
Aggregationindex
Southern site
1978 1985 1992 1978 1985 1992 Percent change 1978–1985
Remote 40 45 89 20,127 20,203 16,803 0.38 12.50 0.54
Afro-Caribbean/indigenoussettled
116 93 122 11,011 13,440 11,077 22.06 -19.83 1.48
Migrantsettled
11 24 9 10,715 9,780 9,952 -8.73 118.18 -1.10
Percent change 1985–1992
Remote -16.83 97.78 -4.41
Afro-Caribbean/indigenoussettled
-17.58 31.18 -3.77
Migrantsettled
1.76 -62.50 0.04
Northern site
1978 1988 1992 1978 1988 1993 Percent change 1978–1988
Remote 1,364 1,476 1,924 51,806 52,206 51,746 0.77 8.21 0.58
Afro-Caribbean/indigenoussettled
1,241 1,323 2,189 37,561 41,183 36,148 9.64 6.61 2.05
Percent change 1988–1993
Remote -0.88 30.35 0.70
Afro-Caribbean/indigenoussettled
-12.23 65.46 -0.06
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they were the first dates after these events in which we could acquire cloud-free imagery
for the study sites. By 1992, the number of refugees leaving Nicaragua had declined (The
UN Refugee Agency 2011) and many refugees had already resettled along the Atlantic
Coast and begun the process of rebuilding their homes and restoring and expanding
agricultural fields. Of the documented refugees repatriated from 1980 to 1995, approxi-
mately 58% returned between 1989 and 1992 (over 46,000 people), almost all of them
arrived from Honduras and Costa Rica (The UN Refugee Agency 2011). Therefore, our
estimates of forest cover loss between pre- and post-conflict are overstated because the
post-conflict dates of analysis are 3–4 years after the conflict ended.
We also hypothesized that an increase in fragmentation would take place in areas of
human settlement between pre- and post-conflict time periods, quantified by numbers of
patches and aggregation indices. Results provided mixed support for this hypothesis. All
regions, with the exception of the migrant-settled region, became more fragmented
between pre- and post-conflict according to the number of patches. The number of patches
decreased in the Afro-Caribbean and indigenous settled area of the southern site in the first
interval, but then increased substantially in the second interval, resulting in a net gain in
number of patches between pre- and post-conflict, which is partially explained by the
hurricane. Areas around small communities were dominated by a matrix of agriculture and
forest, thus allowing space for forest regrowth and potentially increased connectivity
Fig. 3 Forest cover change in northern site: a from 1978 to 1988, b 1988–1993 and c 1978–1993
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between patches. Trends in the settled area of the northern site supported our hypothesis—
the number of patches almost doubled between pre- and post-conflict periods.
While increases in numbers of patches often indicate a decrease in aggregation, this is
not always the case. Our results suggested small increases in forest aggregation in all study
areas, except the migrant-settled region, in the first interval. Interestingly, these increases
took place while the total number of forest patches also increased. This phenomenon is
possible because number of patches do not necessarily decrease linearly as aggregation
increases (He et al. 2000), leaving open the potential for different land cover configurations
to produce these results. In this case, the increase in forest patches may be attributed to
several smaller non-forested patches regenerating to forest, thereby increasing the overall
forest area, in addition to increasing the number of forest patches. As forest area increased,
the likelihood for the presence of adjacent forest patches increased, creating higher AI
Fig. 4 Changes in forest cover along Nicaragua’s Atlantic Coast during the civil war, along with U.S.Congressional funding and Nicaraguan refugee movements from 1982 to 1994
Table 4 Timeline of importantconflict-related events
1978 Pre-conflict Landsat images for southern and northernsite
1979 Sandinistas overthrow Somoza regime
1982 U.S. Congress begins funding Contras (Sobel 1995)
1985 Second Landsat image for southern site
1988(April)
Second Landsat image for northern site
1988(Oct)
Hurricane Joan
1988 Sapoa ceasefire
1989 Civil war ended (Centre for the Study of Civil War 2009)
1990 Sandinistas defeated in elections. U.S. Congress endedsupport for Contras (Sobel 1995).
1992/93 Post-conflict Landsat images for southern and northernsite
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values. Overall, small changes in values across all study areas did not provide substantial
results from which to determine whether fragmentation increased or decreased between
pre- and post-conflict, when measured by the AI.
One potential cause of land use change coincided with the change in government and
thus, the conflict. The Sandinistas instituted a policy of land reform in which landless
peasants received title to lands. Agricultural land held under cooperatives increased by
21% between 1978 and 1987 (Heiner et al. 1989) and more than 80,000 families in
Nicaragua received title to their lands (Carman 1988). Presumably, this reduced the
necessity to deforest an area as a means of demonstrating ownership and contributed to a
reduction in forest loss (Rice 1989; Vandermeer 1991; Stanfield 1995). Another factor
contributing to reduced forest loss is a decline in agricultural productivity that occurred
during the war. Reports indicate that agricultural activities were significantly disrupted
during the conflict. In northwest Nicaragua, crop production data from the Nicaraguan
government and Landsat MSS analysis indicated that agricultural land in production at the
beginning of the conflict in 1979–1980 was less than 60% of 1972–1973 levels because
fighting interfered with planting and prevented people from attending to agricultural plots
(Howe 1983). On the Atlantic Coast where agricultural plots are typically located outside
communities and nested in a forest and agricultural matrix, there was a similar withdrawal
from agricultural activities because of fear of violence or assault while distant from human
settlement (Barbee 1997; Christie et al. 2000). Studies from Bosnia and Sri Lanka during
conflict also demonstrate that agricultural fields were abandoned (Suthakar and Bui 2008;
Witmer and O’Loughlin 2009).
There are ten communities in the southern site and all but one is comprised of indig-
enous and Afro-Caribbean groups that rely to varying degrees on farming and fishing for
their livelihood. The only community in the site that is not majority indigenous is Pueblo
Nuevo, a Mestizo community on the Wawashang River. They do not typically fish as a
livelihood and rely to a greater extent on livestock production requiring pasture than
groups like the Miskitu, Garifuna or Creole people. This variation in livelihood strategy
may explain the contrasting trend in forest cover change of the Pueblo Nuevo region during
both time intervals relative to the other areas of the southern site.
The rate and type of forest regeneration after disturbance is influenced by several factors,
including the type of disturbance, landscape configuration, soil type, and species present
(Guariguata and Ostertag 2001; Chazdon et al. 2007). The forests of the southern study site
recovered from two major and distinct disturbance events—that of recovery from agriculture
abandonment and from Hurricane Joan, while the northern site recovered primarily from
agricultural abandonment. What is the potential composition and ecological value of these
regenerated forests? Agricultural land in the study site consists of small plots for subsistence
purposes, using low-intensity techniques of agro-forestry nested within a forest and agri-
culture matrix. This type of land-use is characterized by access to a seed bank, low soil
disturbance, as well as the presence of remnant vegetation, all features that lead to a more
rapid recovery from disturbance (Guariguata and Ostertag 2001; Chazdon 2003; Chazdon
et al. 2007). Category 4 Hurricane Joan devastated the southern Atlantic Coast in late
October 1988, felling large forest tracts in the southern site. An estimated 500,000 ha of
forest were damaged at the eye of the storm with impacts extending 50 km inland (Will 1991;
Yih et al. 1991). Though the eye of the storm was 55–135 km south of the sites, the hurricane
damaged areas as far north as La Fe (Sandra Sambola, personal communication, see Fig. 1).
The resulting forests after these transition stages are not uniform in terms of their
conservation value, which varies widely depending on the species, the metric used for
measuring diversity, and the scale of disturbance preceding regeneration. In a study
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conducted 5-years post-hurricane on the Atlantic Coast of Nicaragua (south of our study
site) comparing succession in post-hurricane forests and post-agriculture forests, Boucher
et al. (2001) found that successional species between these two disturbance areas were
distinct and that post-hurricane forests had greater tree species richness and evenness.
Forests regenerating from agriculture in our study site could be expected to host Cecropia,
Miconia and Vismia species 5 years after abandonment, while hurricane-damaged forests
would be dominated by species present in pre-hurricane forest such as Macrolobium spp.,
Vochysia ferruginea and Cupania glabra (Boucher et al. 2001). There were several tran-
sitions in land-use evident in the study site. Some areas became forested in the first interval
and changed back to non-forest in the second interval. The varying ability of taxa to persist
in secondary forests is an area of ongoing investigation (Barlow et al. 2007; Parry et al.
2007; Gardner et al. 2009; Chazdon et al. 2009; DeClerck et al. 2010) though large
mammals of conservation concern such as jaguar Panthera onca, Baird’s tapir Tapirusbairdii, and white-lipped peccary Tayassu pecari are known to use secondary forests
(Carrillo et al. 2002; Foerster and Vaughan 2002; Foster et al. 2010). As the area of land
covered in secondary forests expands globally [Food, Agriculture Organization (FAO)
2007], the species assemblage of these forests has important conservation implications.
Understanding how forest cover is affected during periods of conflict and the causes of
this change will help conservationists and managers protect resources in the tumultuous
period following the cessation of violence when nascent governments lack power to
effectively govern and community institutions are fractured by war. During this time,
exploitation is often uncontrolled and is a potential opportunity for conservation inter-
vention to buttress community institutions and prevent substantial losses to biodiversity
(Hatton et al. 2001). The effects of the conflict are still felt along the Atlantic Coast today
as refugees escaping violence around small communities never returned from city centers,
livelihoods and gender roles shifted as a result of diminished ability to practice agriculture,
hunt or fish during the war and social dynamics were altered as a result of differing
political affiliations and alliances (Barbee 1997; Christie et al. 2000). This study highlights
heterogeneity in the effects of war on forest cover based on potential variation in liveli-
hoods, policy, land tenure and the manifestation of other external forces. In areas where the
livelihoods of people are directly dependent on local resources, anticipating ecological and
social impacts will help improve economic and natural security for post-conflict
restoration.
Acknowledgments We would like to thank the Center for Global Change and Earth Observation atMichigan State University and the National Science Foundation (CNH-0815966) for their support in con-ducting this research. We also thank Olivia Courant for background and field research that contributed to thedevelopment of the paper. An anonymous reviewer gave valuable comments and suggestions.
References
Anderson J, Hardy E, Roach J, Witmer R (1976) A land use and land cover classification system for use withremote sensor data. Geological Survey Professional Paper 964
Bannari A, Morin D, Benie G, Bonn F (1995) A theoretical review of different mathematical models ofgeometric corrections applied to remote sensing images. Remote Sens Rev 13:27–47
Barbee S (1997) Women as agriculture producers in the Pearl Lagoon. Wani 22:6–22Barlow J, Gardner T, Arauo I, Avila-Pires T, Bonaldo A, Costa J, Esposito M, Ferreira L, Hawes J,
Hernandez M, Hoogmoed M, Leite R, Lo-Man-Hung N, Malcolm J, Martins M, Mestre L, Mirando-Santos R, Nunes-Gutjahr A, Overal W, Parry L, Peters S, Ribeiro-Junio M, da Silva M, da Silva MottoC, Peres C (2007) Quantifying the biodiversity value of tropical primary, secondary and plantationforests. Proc Natl Acad Sci USA 47:18555–18560
Biodivers Conserv
123
Basok T (1990) Repatriation of Nicaraguan refugees from Honduras and Costa Rica. J Refugee Stud3:281–297
Boucher D, Vandermeer J, de la Cerda I, Mallona M, Perfecto I, Zamora N (2001) Post-agriculture versuspost-hurricane succession in southeastern Nicaraguan rain forest. Plant Ecol 156:131–137
Campbell D, Hammond D (eds) (1989) Floristic inventory of tropical countries. New York BotanicalGarden, New York
Carman D (1988) Agrarian reform and deforestation in Nicaragua, The Somoza and Sandinista cases.Thesis, University of Wisconsin
Carrillo E, Saenz J, Fuller T (2002) Movements and activities of white-lipped peccaries in CorcovadoNational Park, Costa Rica. Biol Conserv 108:317–324
Centre for the Study of Civil War (2009) Armed conflicts dataset, Version 4. Centre for the Study of CivilWar, Oslo. http://www.prio.no/CSCW/. Accessed 29 Jan 2011
Chavez P Jr (1996) Image-based atmospheric corrections—revisited and improved. Photogramm EngRemote Sens 62:1025–1036
Chazdon R (2003) Tropical forest recovery: legacies of human impact and natural disturbances. PerspectPlant Ecol Evol Syst 6:51–71
Chazdon R, Letcher S, van Breugel M, Martınez-Ramos M, Bongers F, Finegan B (2007) Rates of change intree communities of secondary Neotropical forests following major disturbances. Phil Trans Royal SocB 362:273–289
Chazdon R, Peres C, Dent D, Sheil D, Lugo A, Lamb D, Stork N, Miller S (2009) The potential for speciesconservation in tropical secondary forests. Conserv Biol 23:1406–1417
Christie P, Bradford D, Garth R, Gonzalez B, Hostetler M, Morales O, Rigby R, Simmons B, Tinkam E,Vega G, Vemooy R, White N (2000) Taking care of what we have. Center for Investigation andDocumentation of the Atlantic Coast (CIDCA)
Conca K, Wallace J (2009) Environment and peacebuilding in war-torn societies: lessons from the UNenvironment program’s experience with postconflict assessment. Glob Gov 15:485–504
DeClerck F, Chazdon R, Holl K, Milder J, Finegan B, Martinez-Salinas A, Imbach P, Canet L, Ramos Z(2010) Biodiversity conservation in human-modified landscapes of Mesoamerica: past, present andfuture. Biol Conserv 143:2301–2313
Foerster C, Vaughan C (2002) Home range, habitat use, and activity of Baird’s tapir in Costa Rica.Biotropica 34:423–437
Food, Agriculture Organization (FAO) (2007) State of the world’s forests. FAO, RomeFoster R, Harmsen B, Doncaster C (2010) Habitat use by sympatric jaguars and pumas across a gradient of
human disturbance in Belize. Biotropica 42:724–731Gardner T, Barlow J, Chazdon R, Ewers R, Harvey C, Peres C, Sodhi N (2009) Prospects for tropical forest
biodiversity in a human-modified world. Ecol Lett 12:561–582Geoghegan J, Villar S, Klepeis P, Mendoza P, Ogneva-Himmelberger Y, Chowdhur R, Turner B, Vance C
(2001) Modeling tropical deforestation in the southern Yucatan peninsular region: comparing surveyand satellite data. Agric Ecosyst Environ 85:25–46
Gergel S, Turner M (eds) (2002) Learning landscape ecology: a practical guide to concepts and techniques.Springer, New York
Guariguata M, Ostertag R (2001) Neotropical secondary forest succession: changes in structural andfunctional characteristics. For Ecol Manag 148:185–206
Hanson T, Brooks T, Da Fonseca G, Hoffmann M, Lamoreux J, Machlis G, Mittermeier C, Mittermeier R,John P (2009) Warfare in biodiversity hotspots. Conserv Biol 23:578–587
Hatton J, Couto M, Oglethorpe J (2001) Biodiversity and war: a case study of Mozambique. BiodiversitySupport Program, Washington
He H, DeZonia B, Mladenoff D (2000) An aggregation index (AI) to quantify spatial patterns of landscapes.Landscape Ecol 15:591–601
Heiner H, Heiner D, Lowell K (1989) Forest utilization in war-torn Nicaragua. J For September:38–45Howe D (1983) The mapping of an agricultural disaster with Landsat MSS data: the disruption of Nica-
raguan agriculture 1979. Dissertation, University of WisconsinInternational Union for Conservation of Nature (2011) IUCN red list of threatened species. Version 2010.3.
www.iucnredlist.org. Accessed 18 Jan 2011Jensen J (1996) Introductory digital image processing: a remote sensing perspective, 2nd edn. Simon &
Schuster, Upper Saddle RiverJohannesson G (2004) How ‘cod war’ came: the origins of the Anglo-Icelandic fisheries dispute 1958–61.
Hist Res 77:543–574Lamb R (1985) Vietnam counts forest and species loss after years of war and colonial rule. Ambio 14:6
Biodivers Conserv
123
Le Billon P (2000) The political ecology of transition in Cambodia 1989–1999: war, peace and forestexploitation. Dev Chance 31:785–805
Lillesand T, Kiefer R, Chipman J (2004) Remote sensing and image interpretation. Wiley, HobokenMartin L, Howarth P (1989) Change-detection accuracy assessment using SPOT multispectral imagery of
the rural-urban fringe. Remote Sens Environ 30:55–66Mas J, Ramirez I (1996) Comparison of land use classifications obtained by visual interpretation and digital
processing. ITC J 3–4:278–283Mather P (2004) Computer processing of remotely sensed images: an introduction, 3rd edn. Wiley, West
SussexMcGarigal K, Cushman S, Neel M, Ene E (2002) FRAGSTATS: spatial pattern analysis program for
categorical maps. http://www.umass.edu/landeco/research/fragstats/fragstats.html Accessed 29 Jan2011
Mertens B, Lambin E (1997) Spatial modeling of deforestation in southern Cameroon: spatial disaggre-gation of diverse deforestation processes. Appl Geogr 17:143–162
Moran E, Brondizio E, Mausel P, Wu Y (1994) Integrating Amazonian vegetation, land-use, and satellitedata. BioScience 44:329–338
Nietschmann B (1990) Conservation by conflict in Nicaragua. Nat Hist 99:42–49Olson D, Dinerstein E, Wikramanayake E, Burgess N, Powell G, Underwood E, D’amico J, Itoua I, Strand
H, Morrison J, Loucks C, Allnutt T, Ricketts T, Kura Y, Lamoreux J, Wettengel W, Hedao P, KassemK (2001) Terrestrial ecoregions of the world: a new map of life on earth. BioScience 51:933–938
Parry L, Barlow J, Peres C (2007) Large-vertebrate assemblages of primary and secondary forests in theBrazilian Amazon. J Trop Ecol 23:653–662
Prevost G (1987) The ‘‘Contra’’ war in Nicaragua. Confl Quart 7:5–21Puyravaud J (2003) Standardizing the calculation of the annual rate of deforestation. For Ecol Manag
177:593–596Rice R (1989) A casualty of war: the Nicaraguan environment. Technol Rev 92:62–72Ross M (2004) How do natural resources influence civil war? Evidence from thirteen cases. Intl Org
58:35–67Roth L (1992) Hurricanes and mangrove regeneration: effects of Hurricane Joan, October 1988, on the
vegetation of Isla de Venado, Bluefields, Nicaragua. Biotropica 24:375–384Skole D, Tucker C (1993) Tropical deforestation and habitat fragmentation in the Amazon: satellite data
from 1978 to 1988. Science 260:1905–1910Sobel R (1995) Contra aid fundamentals: exploring the intricacies and the issues. Political Sci Quart
110:287–306Sollis P (1989) The Atlantic Coast of Nicaragua: development and autonomy. J Lat Am Stud 21:481–520Stanfield J (1995) Insecurity of land tenure in Nicaragua. Research paper 120. Land Tenure Center, Uni-
versity of Wisconsin, MadisonSteininger M (1996) Tropical secondary forest regrowth in the Amazon: age, area and change estimation
with thematic mapper data. Int J Remote Sens 17(1):9–27Suthakar K, Bui E (2008) Land use/cover changes in the war-ravaged Jaffna Peninsula, Sri Lanka, 1984–
early 2004. Singap J Trop Geogr 29:205–220Sutherland W, Adams W, Aronson R, Aveling R, Blackburn T, Broad S, Ceballos G, Cote I, Cowling R, Da
Fonseca G, Dinerstein E, Ferraro P, Fleishman E, Gascon C, Hunter M Jr, Hutton J, Kareiva P, KuriaA, Macdonald D, Mackinnon K, Madgwick F, Mascia M, McNeely J, Milner-Gulland E, Moon S,Morley C, Nelson S, Osborn D, Pai M, Parsons E, Peck L, Possingham H, Prior S, Pullin A, Rands M,Ranganathan J, Redford K, Rodriguez J, Seymour F, Sobel J, Sodhi N, Stott A, Vance-Borland K,Watkinson A (2009) One hundred questions of importance to the conservation of global biologicaldiversity. Conserv Biol 23:557–567
Taylor B (1963) An outline of the vegetation of Nicaragua. J Ecol 51:27–54The UN Refugee Agency (2011) UNHCR statistical online population database. http://apps.who.int/
globalatlas/default.asp. Accessed 13 Jan 2011Uhl C, Jordan J (1984) Succession and nutrient dynamics following forest culling and burning. Ecology
65:1476–1490United Nations Environment Program (2007) Sudan post-conflict environmental assessment, NairobiVandermeer J (1991) Environmental problems arising from national revolutions in the third world: the case
of Nicaragua. Soc Text 28:39–45Vilas C (1989) State, class & ethnicity in Nicaragua. capitalist modernization and revolutionary change on
the Atlantic Coast. Lynne Rienner Publishers, Inc, BoulderWearne P (2002) Nicaragua economy. In: West J (ed) South America, Central America, and the Caribbean
2003, vol 11. Europa Publications, London, pp 601–605
Biodivers Conserv
123
Will T (1991) Birds of a severely hurricane-damaged Atlantic Coast rainforest in Nicaragua. Biotropica23:497–507
Witmer F, O’Loughlin J (2009) Satellite data methods and application in the evaluation of war outcomes:abandoned agricultural land in Bosnia–Herzegovina after the 1992–1995 conflict. Ann Assoc AmGeogr 99:1033–1044
Yih K, Boucher D, Vandermeer J, Zamora N (1991) Recovery of the rainforest of Southeastern Nicaraguaafter destruction by Hurricane Joan. Biotropica 23:106–113
Biodivers Conserv
123