An assessment of biodiversity hotspots using remote sensing and GIS

Abstract

This study focuses on the assessment of the status of world’s remaining closed forests (WRCF), population distribution, and
protected areas in global biodiversity hotspots using remote sensing and Geographic Information System (GIS). Conservation
International (CI) has identified 25 eco-regions, called biodiversity hotspots that are especially rich in endemic species
and are particularly threatened by human activities. This study uses globally consistent and comprehensive geo-spatial data
sets generated using rerriote sensing and other sources, and the application of GIS layering methods. The consistent data
set has made it possible to identify and quantify relationships between the WRCF, human population, and protected areas in
biodiversity hotspots. It is expected that such information will provide a scientific basis for biodiversity hotspots management
and assist in policy formulations at the national and international levels.

Full text

Photonirvaehak
Journal of the Indian Society of Remote Sensing, Vol. 30, No. l&2, 2002
An Assessment of Biodiversity Hotspots Using
Remote Sensing and GIS
HUA SHI and ASHBINDU SINGH
Division of Environmental Information, Assessment and Early Warning - North America
USGS/EROS Data Center, Sioux Falls, SD 57198, USA
ABSTRACT
This study focuses on the assessment of the status of world's remaining closed forests
(WRCF), population distribution, and protected areas in global bjodiversity hotspots using
remote sensing and Geographic Information System (GIS). Conservation International (CI)
has identified 25 eco-regions, called biodiversity hotspots that are especially rich in endemic
specie s and are particularly threatened by human activities. This study uses globally
consistent and comprehensive geo-spatial data sets generated using remote sensing and other
sources, and the application of GIS layering methods. The consistent data set has madd it
possible to identify and quantify relationships between the WRCF, human population, and
protected areas in biodiversity hotspots. It is expected that such information will provide a
scientific basis for biodiversity hotspots management and assist in policy formulations at the
national and international levels.
Introduction
Biodiversity, simply defined as the total of
all life on Earth, that wealth of species, said and
done, still the only place in the entire universe
where we know with certainty ecosystems, and
ecological processes that make our living planet
what it is -~ after all is that life exists. It is our
living resources base, our biological capital in
the global bank, and what distinguishes it
Recd. 3 Jan., 2002; in final form 18 April., 2002
perhaps more than anything else is the fact that
its loss is an irreversible process (Mittermeier
et
al.,
1999). The Global Biodiversity Assessment
(1992) of the United Nations Environment
Programme (UNEP) concluded that the adverse
effects of human impacts on biodiversity are
increasing dramatically and are threatening the
very foundation of sustainable development. The
total number of species that inhabit th6 planet is
unknown and it is believed that many extinctions
will occur even before they are n~imed and
described. It is estimated that 85-90% of all

106 Hua Shi and Ashbindu Singh
species can be protected by setting aside areas of
high biodiversity before they are further
degraded. Most terrestrial species are found in
the tropics, only a relatively small portion of the
total land area is likely to be devoted to
biodiversity conservation; hence, it is critical to
geographically identify such areas rich in species
diversity and endemism as a first step toward the
protection of remaining natural habitats.
The next half-century could be called the "last
chance decades". These will be some of the most
dangerous years ever for the Earth's species and
ecosystems. Yet this is also a time in which we
have a chance to make a difference (Mittermeier
et aL, 1999). In the past, protected areas have
been often set aside without regard to the
biodiversity within their boundaries. As a result,
many protected areas have little significance in
terms of biodiversity, and conversely, many
areas of habitat with significant biodiversity lack
protection. This study seeks to identify
relationships between the WRCF, human
population, and protected areas by analyzing
comprehensive and consistent spatial data sets of
1-km resolution to answer following questions:
9 What is the distribution of the WRCF in
biodiversity hotspots?
9 Are the world's remaining closed forests
with significant biodiversity adequately
protected?
9 Is biodiversity within the WRCF threatened
by human population pressure and land use?
9 What are the inter-connections between
people and the biodiversity hotspots?
What should we do?
Data
Global Forest Cover Distribution Data
In this study the USGS land cover database
(Loveland et al., 2000) has been used as a base to
update forest cover map for many parts of the
world for the year 1995. This land cover
database was developed on characteristics of
vegetation seasonality determined in terms of
weekly composite of Normalized Difference
Vegetation Index (NDVI) derived from the
National Oceanic Atmospheric Administration
Advanced Very High Resolution Radiometer
(NOAA AVHRR) sensor for the period 1992-
1993 (http://edcdaac.usgs.gov). In. the database,
unique NDVI signatures and associated
attributes, such as terrain and eco-regions,
characterize large-area land cover patterns
(Singh et aL, 2001). In the present study, area
under forests classes, namely, closed forests
(density > 40%), open and degraded forests
(density 10-40%), and other woodlands were
taken from the 1995 forest cover database,
whereas area under grassland, cultivation, and
water were taken from the USGS land cover
database.
Global Population Database
The geographically referenced population
database was provided by the UNEP/GRID
(http://grid.cr.usgs.gov). These data sets were
generated using a model incorporating many
variables.
Global Protected Area Database
UNEP-World Conservation Monitoring
Center (UNEP_WCMC) (http://www.unep-
wcmc.org) has provided the protected areas
database. The definition of a protected area as
adopted by The World Conservation Union
(IUCN) is "An area of land and/or sea especially
dedicated to the protection and maintenance of
biological diversity, and of natural and
associate.d cultural resources, and managed
through legal or other effective means" (2001).
Biodiversity Hotspots
The Conservation International (CI) has
provided the biodiversity hotspots database
(2001, http://www.conservation.org). The
hotspots are considered to be Earth's biologically
the richest and most endangered terrestrial eco-
regions. The Conservation International have
identified 25 hotspots which are: Atlantic Forest
region, Brazilian Cerrado, California Floristic
Province, Cape FIoristic Region Caribbean,

An Assessment of Biodiversity Hotspots Using Remote Sensing and GIS... 107
Caucasus, Central Chile, Choco-Darien-Western
ECuador, Eastern Arc Mountains and Coastal
Forest, Guinean Forests of West Africa, lndo-
Burma, Madagascar and Indian Ocean Islands,
Mediterranean basin, Mesoamerica, Mountains
of South Central China, New Caledonia, New
Zealand, Philippines, Poynesia and Micronesia,
Southwest Australia, Succulent Karoo,
Sundaland, Tropical Anded, Wallacea, Western
Ghats and Sri Lanka. The three major tropical
wilderness areas are Upper Amazonia and
Guyana Shield, Congo River Basin, and New
Guinea and Melanesian Islands (Mittermeier et
al., 1999).
Political Boundaries Data
Political boundaries data has been taken from the
US National Imagery and Mapping Agency's
(NIMA) Vector Map Level 0 (VMAP0) series
CD-ROM. From this data set, year 1995 version
of the political boundaries of the world at 1:1
million nominal scale was taken. Attribute
assignments were verified and corrected as
needed for the resulting polygon coverage and
subsequently these coverages were joined to
generate an updated map.
General Considerations About The Data
The forests cover and population data sets
were the best available that covered the entire
world. Local errors are known to exist in the
mapped distribution of forests cover type. The
population distribution data set was generated
using a spatial modeling technique incorporating
many variables.
The recent database on protected areas were
not available for all countries. Some of the
smaller protected areas may not have been
accounted for due to the coarse resolution of
data. Where information is not available for the
exact extent of a protected area, a point was
inserted representing the center of the site.
Polygons were made for such locations by using
the information in textual databases and drawing
a circular polygon of the relevant area around the
point location of the site. None of these data sets
have been rigorously validated, so local
relationships and distributions should be viewed
with caution. Availability of high-quality, current
global data remains a stubborn barrier in such
analyses, highlighting the need to support
development and updating of such databases.
Global 1-km AVHRR data [
(Remote Sensing) Other global data layers:
Biodiversity population, protected
hotspots boundary areas, country boundary
Global forests cover
~~'~Overlaying ~~ '//
GIS
I Analysis and assessment of global biodiversity hotspot
-
Fig. 1. Data analysis procedure

Fig. 2. The WRCF cover with designated protected areas in the biodiversity hotspots and three major tropical
wilderness areas. Hotspots: (1) Tropical Andes; (2) Mesoamerica; (3) Caribbean; (4) Atlantic Forest region; ~5)
Choco-Darien-Western Ecuador; (6) Brazilian Cerrado; (7) Central Chile: (8) California Floristic Province; (9)
Madagascar; (10) Eastern Arc Mountains and Coastal Forests of Tanzania and Kenya; (11 ) West Africa Forests;
(12) Cape Floristic Region; (13) Succulent Karoo; (14) Mediterranean Basin; (15) Caucasus; (16) Sundaland; (17)
Wallacea; (18) Philippines; (19) Indo-Burma; (20) Mountains of South-central China; (21) Western Gats and Sri
Lanka; (22) Southwest Australia; (23) New Caledonia; (24) New Zealand; arid (25) Polynesia and Micronesia.
Maior tropical wildeness areas: (A) Upper Amazonia and Guyana Shield; (B) Congo River Basin~ (C) New Guinea
and Melanesian Islands.
Fig. 3. Population pressure in and around WRCF in 25 hotspots and three major tropical wilderness areas
( 1-25 and A-B; see map for names and locations Fig. 2)

Fig. 4. Human population live in and around WRCF in 25 hotspots and three tropical wilderness areas (I-25 and A-
B; see map for names and locations Fig. 2). Green: percentage of low population pressure; Yellow: percentage of
medium population pressure; and Red: percent of high population pressure.

108 Hua Shi and Ashbindu Singh
Methodology
Data was processed using remote sensing
and GIS software package (ERDAS Imagine and
Arc/Info, 2000). Most of the work was carried
out in the GRID module of ARC/INFO. Raster
and vector data layers were in an Interrupted
Goode Homolosine Projection, which is an equal
area projection. All raster data sets had a cell size
of 1000 m (1-km), Fig. 1.
The data layers were analyzed individually
or combined with other data layers in order to
see possible interrelations or possible spatial
relationships among them. For example, the
original extent of biodiversity hotspots layer,
population density layer and country boundaries
layer were digitally overlaid in order to assess
the population pressure on the each hotspot by
countries.
The
World's Remaining Closed Forests
Detailed analysis of forest cover for each
original extent of the 25 biodiversity hotspots
and three extensive tropical wilderness areas
(Myers
et al.,
2000), derived from the NOAA
AVHRR for the period 1995 (Singh
et al.,
2001),
was utilized to assess the actual extent and
distribution of the remaining closed forests.
Closed forest is defined as lands of forest cover
with canopy .density of 40% and greater. The
definition of 40% coverage is appropriate
because it can be estimated with ease: when the
coverage of the trees is 40% the distance
between two tree crowns equals the mean radius
of a tree crown (UNESCO, 1973).
The closed forest cover distribution by
biodiversity hotspots was estimated by
combining original extent of hotspots boundary
grids with the closed forests cover classes. In
each hotspot, the total number of closed forest
coverceUs was summed and then divided by the
original extent of the area, thus resulting in the
percent area covered by closed forests within
each hotspot. Conservation International
provided the original the biodiversity database.
Protection status
The protected area status of the closed
forests in 25 biodiversity hotspots and 3
wilderness was estimated by combining the
protected area grid with the closed forests
distribution grid, and biodiversity hotspots
boundary grid. Within each protected area, the
number of closed forests cover cells were
counted and then summed by each hotspot for
each closed forest area.
Population distribution and pressure
The number of people was estimated for
closed forest area by each hotspot or countries.
The resulting data has been exported as a
spreadsheet and combined in one graph showing
the population distribution of the closed forests
in each hotspot. The following classification was
used for the analysis of population pressure in
closed forests: (a) low population pressure: < 25
people km -2, (b) medium population pressure:
25-100 people km -2 and (c) high population
pressure: > 100 people km-L
Results and Discussion
The
world's remaining closed forests in the
biodiversity hotspots
The extent of the World's Remaining Closed
Forests (WRCF) in 1995 is estimated at
approximately 2.87 billion hectares, which
occupies about 21.4% of land area of the world
(Table 1). The WRCF occupies about land area
9.25% in Africa, 16.8% in Australia and Pacific,
21.1% in Europe.and Asia, 29% in North and
Central America and 35.44% in South America.
Percentage of WRCF to the total land area is
highest in South America and the lowest in
Africa.
We estimated that the WRCF occupied
25.5%
of the land area in 25 hotspots and 79.5%
9 in three wilderness areas in 1995 (Fig. 2).
The WRCF patterns with protected status in
25 hotspots and three major wilderness areas are
apparent in Fig. 2. The broadest areas of the
WRCF (>30%) can be seen in Wallacea,

An Assessment of Biodiversity Hotspots Using Remote Sensing and GIS... 109
Table
1: Distribution of the WRCF with protected areas in 25 hotspots and 3 wilderness areas km 2, per cent
Biodiversity Hotspots
OE 1
Area per cent
PT 2
WRCF
Total 8703263 18.18
World 24333252 11.83
Congo River basin
New Guinea and Melanesian Is-
lands
2050680 9.68
914016 15.44
Cape Floristic Region 74771 0.98
Caribbean 247423 8.77
Caucasus 556246 2.92
Central Chile 289627 6.21
Choco-Darien-Western Ecuador 223984 10.69
Eastern Arc Mountains and Coastal 191828 15.85
Forests
Guinean Forests of West Africa 879511 4.06
Indo-Burma 2273303 9.08
Madagascar and Indian Ocean 597673 1.12
Islands
Mediterranean Basin 520177 1.83
Mesoamerica 1144270 9.72
Mountains of S. Central China 557260 5.36
New Caledonia i 7301 1.53
New Zealand 257698 11.13
Philippines 280545 3.86
Polynesia and Micronesia 1404 0.37
Southwest Australia 306903 7.04
Succulent Karoo 102840 1.71
Sundaland 1475121 13.10
Tropical Andes 1396569 14.46
Wallacea 317927 13.49
Western Ghats and Sri Lanka 254730 9.09
Total 15629989 8.29
Upper Amazonia and Guiyana 5738567 21.66
Shield
Atlantic Forest 1480400 0.83 106599 7.20 5.07
Brazilian Cerrado 1830910 6.18 253820 ! 3.86 14.47
California Flofistic Province 351568 38.63 134730 38.32 65.84
2601 3.48 0.00
74274 30.02 16.24
.73448 13.20 7.01
60983 21.06 17.94
78354 34.98 14.76
20170 10.51 7.65
280258 31.87 5.34
777654 34.21 14.05
84454 14.13 3.13
25892 4.98 4.07
581703 50.84 14.07
187918 33.72 7.36
3687 21.31 4.53
71332 27.68 19.77
69285 24.70 4.49
0 0.00 0.00
21822 7.11 11.56
0 0.00 0.00
628141 42.58 18.50
236975 16.97 25.75
162988 51.27 18.07
43785 17.19 22.90
4E+06 25.47 15.88
4802966 83.70 21.25
1474946
71.92 10.79
638242 69.83 14.40
6916154 79.50 18.39
28723638 21.43 9.4
Note: 1. OE- Original extent of primary vegetation; PT-Designated protected areas
Area per cent of per cent
Area PT

110 Hua Shi and Ashbindu Singh
Mesoamerica, Sundaland, California Floristic
Province, Chaco-Darien-Western Ecuador, Indo-
Burma, Mountains of South-Central China,
Guinean Forests of West Africa, and the
Caribbean. No closed forests existed in
Polynesia, Micronesia, and the Succulent Karoo.
The Mediterranean Basin had the greatest extent
of non-vegetated land, approximately 60%. The
WRCF cover the most areas in the three wildness
areas (all of them > 69%).
The protection status of the WRCF in
biodiversity hotspots
Global protected areas occupy slightly over
10 million sq km or 7.9% of the global land area
(exclude Antarctic) 134 million sq km. About
9.4% of the WRCF have been accorded some
sort of formal protection status, the highest being
in the South America (19.5%) and the lowest
being in the Eurasia (3.9%). Designated
protected areas occupy approximately 8.3% of
the hotspots including 15.9% of the WRCF. The
percentage of protection status for each hotspot
and wilderness area is shown in Table 1. The
lack of designated protected areas within the
hotspots is alarming. The protection status for
most of the 25 hotspots is less than 10% of the
total land and 20% of the WRCF. The hotspot
with the most protection was the California
Floristic Province with 38.6% of the total land
and 65.8% of the WRCF. The WRCF under
protection status in Upper Amazonia and Guiyana
Shield occupy about 1020849 km 2 or 21.3% of the
total the WRCF. These areas contain vast areas of
intact tropical forests which are biologically richest
areas on the earth. The WRCF under protection
status in New Guinea and Melanesian Islands
occupy slightly over 14.4% of the total WRCF.
Papua New Guinea (PNG) still possesses large
areas of the WRCF. About 85% of the WRCF in
PNG are under moderate or high threat, primarily
from logging, agricultural clearing, and mining.
Population Pressure of the WRCF in
Biodiversity Hotspots
In the year 1995, about 22.7 per cent of the
world's population lived in and around the
original extent of hotspots and wilderness areas,
0.35% in and around the WRCF of 25 hotspots
and 0.7% in and around the WRCF of 3 wildness
areas. We found that 18 of the 25 hotspots have
population percent at or higher than the average
of world (12%) in WRCF, and all of three
wilderness areas have low population pressure
(the area of low population pressure in WRCF is
great than 94%) Fig. 3.
We analyzed the population pressure in the
WRCF of the 25 hotspots and three wilderness
areas (Fig. 4). In the year 1995, high human
population pressure in the 25 hotspots exists in
10.7% of the WRCF. If population pressure in
and around the WRCF are examined in isolation
of the other factors, the four hotspots with the
most elevated risks, as assessed by high human
population pressure, are the Western Ghats/Sri
Lanka, Polynesia and Micronesia (no closed
forests), Philippines and Caribbean hotspots,
while almost all vegetation cover and closed
forest areas in New Caledonia, Southwest
Australia and Brazilian Cerrado are free from
high population pressure. Some recent hotspots
analysis conclude that the hottest hotspots appear
to be the highest-priority of these ecoregions on
the basis of their extreme endemism and the
intense packing of species into a much reduced
area of original vegetation. Human activities in
the biodiversity hotspots areas indicate a high
risk that habitats will continue to degrade as
ecosystems dominated by humans expand and
species become extinct in the world's most
biologically diverse terrestrial regions.
The
Inter-Connections Between People and the
Biodiversity Hotspots
After investigating three topics and
resolving some of issues, our final step was to
determine what are the inter-connections
between people and hotspots. Fig. 5 shows
summary of this study.
Human impact on biodiversity hotspots
increases forests ecosystem vulnerability, which
also increases human awareness and stimulates
human efforts to protect the forests ecosystem.

An Assessment of Biodiversity Hotspots Using Remote Sensing and GIS... ! ! 1
Human impact on the
biodiversity hotspots
(Urbanization, land cover
change, biodiversity loss
etc.)
Decreases
Increases
Ecosystem vulnerability
(Pollution, soil erosion
Ecosystem protection
(Protected area, Land use
planning etc.)
t
Increases awareness
Figure 5. An overall framework for inter-connection between people and biodiversity hotspots
This increased awareness hopefully
decreases future human impacts. In future studies
we hope to explore and investigate the processes
that inter-connect the human impact on
biodiversity hotspots, forests ecosystem
vulnerability, and ecosystem protection.
Summary for policy makers
The seographic analysis of relationships between
protected areas and distribution of the WRCF
and population density clearly revealed the
following facts:
1. Lack of (a) protection status and (b)
effective implementation of protection
measures in the designated protected areas
seems to pose a serious threat to the WRCF
biodiversity.
2. This study using geographic information
system techniques estimates that
approximately 9.4% of the WRCF in
worldwide is protected, and this figure is
based on measuring the spatial extent of
protected areas provided by the World
Conservation Monitoring Centre (WCMC).
This is substantially more than the estimate
of approximately 5%, compiled from official
statistics, again from the WCMC, which is
normally cited in international publications.
This discrepancy highlights the need for
better environmental information
infrastructures in countries to generate and
maintain accurate and up-to-date
environmental data for planning and policy
formulation purposes.
3. About 15.88% in 25 hotspots and 18.39% in
three wilderness areas covered by
biodiversity-rich the WRCF is protected.
The majority of these valuable ecoregions,
rich in biodiversity and en~lemic species, are
concentrated in countries like the Mexico,
Columbia, Ecuador, Peru, Brazil,
Democratic Republic of Congo,
Madagascar, China, India, Malaysia,
Indonesia and Australia, which desperately
need more protection. So practical action
programs that include accelerated expansion
of protected area networks are urgently
needed.
4. In most of the WRCF area, the opportunity
still exists for pro-active measures to
conserve biodiversity. Low human
population pressures in many areas provide
an opportunity to protect such areas for
conservation purposes if action is taken now.
5. The presence of the WRCF in legally
protected areas is an indicator that
biodiversity cannot easily be preserved in

112 Hua Shi and Ashbindu Singh
.
the face of human competition for the same
land. To ensure the preservation of
biodiversity, and of endemic and endangered
species, protected status must be
accompanied by effective long-term
enforcement measures. More effort should
be made to understand the socioeconomic
factors associated with the protection of
biodiversity; local stakeholders must have a
role and economic incentives to conserve
biodiversity.
A shift in national and international policy
formulation and planning processes, based
on targeting biodiversity-rich areas, is
needed to protect biodiversity more
effectively in 25 hotspots and three tropical
wilderness areas. Geographic targeting and
programmatic focus are both needed to
conserve ecoregions rich in biodiversity and
endemism, plus address the socioeconomic
causes of encroachment and subsequent loss
of biodiversity.
Acknowledgements
We are grateful to the United Nations
Environmental Programme (UNEP), National
Aeronautics and Space Administration (NASA)
and United States Geological Survey (USGS) for
financial support. We are grateful to Dr. Tom
Loveland, Dr. Zhiliang Zhu and his team for
generating and providing the land cover
distribution data set. Also we appreciate Dr. E.A.
Forsnight, Dr. R. Singh, Mr. R. Auch, Mr. R.
Reker, Mr. M. Ernste and Ms. K. Giese for their
valuable comments and contributions.
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