The project financed by the Swedish Agency for International
Technical and Economic Co-operation
Berdningen för Internationellt Tekniskt-ekonomiskt Samarbete BITS
Welcome to Jamaica
Location of the Black River and Negril wetlands in Jamaica
Summary from Ambio 20, Björk & Digerfeldt, 1991: Development and degradation,
redevelopment and preservation of Jamaican wetlands. - Ambio 20.
In Jamaica, coastal wetlands at Negril and Black River cover 23 and 61 km2, respectively, the latter is divided into the upper (18 km2) and the lower (43
km2) morass (Fig 1-3)
Because Jamaica in the early 1980s was dependent on imported oil for energy
production by more than 90 %, an intensive search for domestic resources was
conducted. As a result, local deposits of peat at Negril and Black River came
into focus. It is estimated that the use of peat in a conventional steam-power
plant could save about 30 % or more of Jamaica's domestic fuel consumption over
a period of c. 30 years (Wade & Reeson 1985). The Jamaican government and
authority responsible for energy production demonstrated an extraordinarily
profound and serious interest in investigating and solving environmental
problems before peat mining started (Wade 1985, Wade & Reeson 1985).
Studies on the environmental feasibility of peat mining and the optimum
utilization of the Negril and Black River Morasses (Björk 1982, 1983, 1984,
1985) clearly indicated that there were great possibilities of combining the
environmental aspects with multipurpose use - including peat mining - and
management of the resources of these two wetlands, provided this was done in an
ecologically realistic and sound way.
The origin and past development of the wetlands has been closely associated with
the Holocene rise in sea level (Digerfeldt & Enell 1984, Digerfeldt & Enell
1985, Digerfeldt & Hendry 1987). When the rising water table reached the deepest
areas of the wetland basins (at Negril 17 m and at Black River 12 m below
present sea level) these areas successively changed to wetlands and peat began
to accumulate. The wetland development until present times, including the
progressive increase of the morass area, the environmental characteristics and
vegetation, and the accumulation of peat, has been determined primarily by the
rise in sea level. After Jamaica was conquered by the Spaniards, and especially
as a result of subsequent British occupation, the wetlands became more and more
influenced by man and degradation set in.
When dealing with the past, present and future wetland development, the morasses
and their respective catchment areas should be treated as coupled units. This
holistic view in time and space is a prerequisite for planning for what is now
called sustainable development, which demands realistic and active management of
the environment with man as an integrated component. The Jamaican wetlands and
their drainage areas may serve as examples that only documentation of past
changes and understanding of present functioning make it possible to predict
future development. This is true at the local as well as at the regional and
This summary concentrates on a discussion of the past, present and future
development of the Black River Lower Morass, but some comments are given also on
the Negril Morass.
The Negril Morass
The Negril Morass
In the late 1950s the Negril Morass was canalised and drained. Nowadays,
saw grass (Cladium jamaicense) is the dominating vegetation species. Especially
during periods with heavy precipitation, a plume of brown water (humic matter)
emanating from the canalised South Negril River extends into the sea at the
southern end of Long Beach, the main tourist attraction.
Starting from the eastern morass margin the peat land was exploited for
extensive illegal cultivation of Cannabis sativa. Because of rapid
mineralization and subsidence as a result of peat aeration, cultivation moved
rapidly westwards, as previously cultivated plots were abandoned. Digging of
canals and ditches, swamp-forest clearing and clear cutting accompanied by slash
and burn methods characterized the preparation of the wetland for production of
From the environmental protection point of view, canalisation and drainage of
the Negril Morass in the late 1950s can be considered the turning point in its
current degradation as a wetland. Illicit cultivation activity has given rise to
the creation of habitats for mosquitoes and sand flies, and devastation of the
The Black River Morasses
Black River Upper and Lower Morasses
The Black River Upper Morass developed throughout as a freshwater wetland and
has been the primary settling basin for matter transported by the Black River,
the main watercourse connecting the Upper and Lower Morasses. At the
same time as the Upper Morass acted as a settling basin, it also functioned as a
sink for nutrients which were adsorbed on particles and assimilated by wetland
The meandering Black River close to its outlet into the
Caribian Sea (S Björk)
The recently drained Upper Morass is now completely separated from the Black
River by dikes and during the 1980s the former wetland was transformed, mainly
for the production of rice. After drainage there is no reduction of nutrients
when the water passes the Upper Morass. On the contrary, the area now acts as a
source of nutrients. As a result of the mineralization following aeration of the
top peat layer, nitrogen is released to the drainage water pumped to the Black
River. The increased concentrations of nutrients in the water drained from the
Upper Morass, including all ongoing aqua- and agricultural activities, cause
increased growth, particularly of water hyacinth (Eichhornia crassipes) and
generally fertilizes the Lower Morass.
Inflow of turbid water from the Black River into the Lower
Morass through man-made openings in the levees (S Björk)
In sharp contrast to the Negril Morass and Black River Upper Morass, the Black
River Lower Morass is, superficially, still in good condition with certain areas
and qualities well preserved. In the longer term there are, however, serious
threats to the Lower Morass as a wetland.
Freshwater supplied to the Lower Morass originates from "blue holes" in the
carstic Tertiary limestone. Among the four main streams of the Lower Morass, the Black and Y.S. Rivers have their springs outside the wetland, at the
margin of the topographically rough Cockpit country. Their drainage areas are
much larger than those of the Middle Quarters River, which is fed from springs
at the north-western edge of the Lower Morass, and the Broad River which
receives its water from magnificent blue springs in the eastern portion of the
The Black River choked with water hyacinth in the Lower
Morass (S Björk)
In Broad River, supplied with crystal-clear water welling up from the limestone
bedrock in circular springs, the concentration of nutrients is very low. Both
the strongly meandering river and the springs are from the bottom to the water
surface delimited by vertical walls of Cladium peat.
Past development of the Black River Lower Morass
The reconstruction of past vegetation was carried out using microscopic peat
identification. The chronology was based on 14C dating, usually at every 2 m
throughout the peat cores. The availability of a large number of dating of basal
peat, representing various depths below present sea level, enabled the
construction of a curve showing the progressive Holocene rise in sea level. Since the Black River area has remained mainly tectonically stable
throughout the Holocene (Hendry 1982, Digerfeldt & Hendry 1987), the curve
correctly indicates the eustatic rise. The reconstruction of the morass area
during selected periods is based on this curve and on a map of the peat
thickness (Robinson 1983) showing the original basin morphology.
The progressive increase of the morass area and the recorded changes in
vegetation and environment over the past 6500 years were made clear.
Generalized sea-level-rise curve for the Black River
|47-4500 BP (-2m)
||2250-2000 BP ()
Reconstructed past vegetation in the Black River Lower Morass during selected
periods. The position of the sealevel according to the curve in fig 6 is given
in the brackets . The identified peat types are formed in
a brachish-marine to brachish environments (i.e.
Rhizophora, Rizophora - Conocarpus, Rizophora Acrosticum , and Rizophora -
Cladium - Conocarpus peat)
b slightly brackish environments (i.e. Cladium -
Rizophora , Cladium - Rhizophora - Concarpus, Concarpus - Cladium , and
Acrosticum - Cladium - Concarpus - Rizophora peat) , and
c freshwater environments (i.e. Cladium and swamp
Effects of climate change
At Black River, 1100 m upstream from the confluence in the Lower Morass with
Frenchman River, 2 m of levee clay is underlain by 2.5 m. of
swamp-forest peat. A 14C dating of the peat immediately below the clay yielded
an age of 2580 BP (Before Present). The Black River levee close to the inflow of
Frenchman River consists of 0.9 m of clay, under laid by 3.5 m of Cladium and
Cladium-Rhizophora peat. Here 14C dating somewhat below the clay yielded the age
of 2720 BP (Digerfeldt & Enell 1984).
The modern vegetation in the Black River Lower Morass
The cause of the incipient levee formation must be an increased soil erosion in
the catchment area of Black River, and an intensified transport of clay and silt
into the wetland. Since this change evidently took place about the same time as
the recorded successive regression of Rhizophora and the seaward transgression
of freshwater vegetation, it seems reasonable that the increase in soil erosion
was caused by a climate change, which implied an increase in humidity. In
addition to accelerated soil erosion, the increase in humidity must have
resulted in an increased inflow of fresh water into the wetland which
consequently reduced the influence of saline water and enabled the seaward
transgression of the freshwater vegetation.
A similar change is also indicated along Y.S. River. Besides initiating or
accelerating levee formation, the increased load of clay and silt of the
inflowing water must also significantly have affected the environment and
vegetation in the areas adjacent to the Black and Y.S. Rivers, which today are
covered by a highly productive vegetation characterized by Typha domingensis
Thalia geniculata. The study of a peat core from the large Typha-dominated area
west of Y.S. River reveals that the present character of the vegetation
represents a late change in the wetland development. From the reconstruction of
past vegetation it appears that the area west of Y.S. River, throughout most
past development, has been occupied not by Typha but by Cladium. The immigration
of Typha occurred some time after a recorded distinct decrease in peat
humification and an equally distinct increase in ash content, which indicates
increased flooding and increased supply of clay and silt. These changes can be
estimated from available 14C dates to have occurred some time between 2500 and
2200 BP, i.e. at approximately the same time as the beginning of the levee
formation along Black River upstream from Frenchman River. The replacement of
Cladium by Typha was certainly an effect of the increased supply of suspended
minerogenic matter and consequently improved tropic conditions. From
reconnoitring studies of some short peat cores, the same changes have taken
place in the vast Typha area east of Y.S. River and the Typha-Thalia area east
of Black River and north of Frenchman River.
Cattle gazing along the levees in the Black River Lower
Morass. In the background vegetation is being burned before cultivation (S
A distinct decrease in peat humification and a fairly common occurrence of
layers of silty and clayey marl, indicating increased flooding, in the upper
part of several of the studied peat cores are further evidence of the suggested
increase in humidity. The available 14C dating of the change in peat
humification vary between 2500 and 1500 BP, which might indicate fluctuations in
the climate change.
The drained Black River upper wetland has been completely
separated from the Black River by dikes (P. Reeson)
Effects of human impact
Distinctly developed levees are also found downstream from the inflow of
Frenchman River into Black River. The layer of clay is, however significantly
thinner than upstream from the confluence. Downstream from the inflow of Middle
Quaters River the levees gradually disappear. Levee transects were studied 750
and 1250 m downstream from Frenchman River, where the vegetation is
dominated by Alpinia allughas (an introduced species, native to S. Asia) on both
the western and eastern river banks and by Typha outside the levees.
Microscopic analyses of the peat immediately below the clay make it clear that
Cladium covered the wetland right to the edge of the river until the levee
formation started. Thus, the conditions were the same here as for the reaches
further upstream where, as described, Typha and Typha-Thalia have invaded areas
formerly dominated by Cladium. However, from 14C datings it appears that the
beginning of the levee formation and the immigration of Typha to the wetland
downstream from the inflow of Frenchman River represents a much later change,
not associated with any climatic change but with recent human activities in the
Black River catchment area.
The 14C dating of the Cladium peat immediately below the levee clay 350 m
downstream from Frenchman River yielded the age 30±45 BP, and the dating 700 m
downstream the age 120±50 BP. Because of the statistical uncertainty of the
dating and the past variation in the atmospheric 14C concentration, it is not
possible to obtain precise determination of age. However, if the dates are
compared with the high-precision calibration curve presented by Stuiver (1982),
it can be established that with 3 σ-confidence the peat was formed within the
last 350 years. The possibility that penetrating roots have had significant
age-reducing effects can be disregarded. During sampling it was observed that
the roots of the present vegetation of Alpinia covering the levees are mainly
confined to the clay layer. The few penetrating roots which were observed in the
sampled peat were removed before the dating.
In view of the settlement history of the area, the incipient formation of levees
downstream from Frenchman River, indicates increased supply and more
long-distance transport than previously of clay and silt from the catchment
area. This should certainly be connected with clearance of forests, sugar-cane
plantations, and cultivation and logging of dyewoods. The latter clearance
started during the British occupation in the 18th and 19th centuries (Wade
1985). These activities must have accelerated soil erosion and resulted in the
intensified supply of clay and silt with river water. Both the extended levees
downstream from Frenchman River and the luxuriant vegetation in this area are
then the result of recent human impact of the watershed area.
The swamp-forest peat underlying the levee clay upstream from the confluence of
Black River and Frenchman River proves that the forest vegetation west of the
former rivers existed in this area throughout the entire past wetland
development. It can be assumed that the increased supply of suspended
minerogenic matter created more solid ground and generally imroved environmental
conditions for the swamp forest.
Effects of recent drainage of the Upper Morass
Before the diking of the reach of Black River that passes the Upper Morass, this
wetland functioned as an important hydrologically buffering basin and as a
settling area for the load of clay and silt supplied by the river from the
watershed upstream of the morass. The clay deposits in the Upper Morass are
thickest along the river, from where they become thinner with increasing
distance. Now the load of clay and silt is instead brought straight into the
Lower Morass, resulting in a further acceleration and downstream transgression
of the levee formation.
In the Black River Lower Morass shrimp (Macrobrachium acanthurus, M. carcinus,
M. faustinum and Jonga serrei) fishery is still of economic importance for the
local population. In order to enable the shrimp to move from the river into the
wetland, the fishermen dig out and keep channels open through the levees. During
flooding the levees are submerged, but turbid and nutrient-enriched river water
is also forced through the openings, thereby causing the changes in the
vegetation described above and accelerating the primary productivity and
terrestrification ("Verlandung") over large areas. Along the levees the
conditions for development of seedlings of opportunistic plant species are much
better than in the wetland covered by Cladium and representing the original poor
conditions of the morass. The settled minerogenic material is very firmly fixed
by the root system of the riparian vegetation. In this way accumulation is
favoured and erosion prevented.
The overall effect of human activities in the catchment area is an ageing of the
wetland. The levees serve as human bridgeheads from which adjacent portions of
the wetland are affected. Successively accessible new areas are utilized for
cattle grazing and cultivation. Foreign plant species are being introduced at
the same time as remaining small native swamp forests are cut down or devastated.
The consequences of the loss of the upper basin have not yet been fully
developed in the Lower Morass. The changes will, therefore, take place at a
greater speed than before, but will follow the same lines indicated so far. It
is not surprising that investigations on the possibilities of converting the
Lower Morass or at least sections of it into arable land have already been
carried out (Japan International Cooperation Agency. 1984.)
Black River Lower Morass Broad River surrounded by mangrove (Rhizophora)
Plans for redevelopment and preservation
The Black River Lower Morass
The general design suggested for rejuvenation and preservation of the Black
River Lower Morass is shown in the map below. The course of the rivers will be
preserved with broad (at least 100 m) zones on both sides, including swamp
forests, mangrove and riparian vegetation.
Areas suggested for peat mining in the Black river
Lower Morass. The proposal is based on consideration of the modern vegetation,
peat - thickness, the nessessity to create sedimentation basins etc.
The eastern section, i.e. the Broad
River area, will basically be left in its present state. It is especially
important not to affect the blue holes and the system for groundwater supply.
The lowproductive sawgrass areas are very extensive and constitute an
impressive counterpart to the areas around the Black and Y.S. Rivers with their
highly productive vegetation of Alpinia allughas, Thalia geniculata, and
Typha domingensis, which indicate a much richer environment than in the other parts of
the wetland, especially those surrounding the nutrient-poor Broad River. It is
suggested that fairly small-scale peat extraction should be allowed within two
areas of the eastern section for production of horticultural peat. In these
areas, the peat deposits are shallow and parts have rather high ash content. In
the lower layers there are soil types which, when constituting the new bottom in
constructed ponds, are suitable for development of submersed vegetation. The
mining should, therefore, result in shallow freshwater lakes with islands and a
rich submersed vegetation (rather clear water). This should imply the creation
of highly attractive waterfowl biotopes.
It is recommended that swamp forests, mangrove and other types of wetland
communities, are exempted from peat extraction. Extraction of fuel peat is
suggested to result in a series of lakes surrounded by gently sloping, irregular
littoral zones. Because freshwater peat dominates the upper parts of the morass
and mangrove peat in the south, a gradient from fresh to brackish will
characterize the water quality of the lakes after mining. Freshwater flow
through some of the lakes can be arranged via intakes and outlets to the rivers.
Lakes adjacent to the Black River will be of great importance as settling basins
for the periodically highly turbid river water. All possible efforts should, of
course, be made to minimize the sediment and increasing nutrient load on the
Black River from the catchment area. An eco-redevelopment program for lakes and
wetlands must always start with necessary regulatory measures in the catchment
area. The water will, however, remain turbid and relatively rich in nutrients.
The freshwater lakes/settling basins created through peat extraction will,
therefore, be productive. Undoubtedly, it will be impossible to avoid infection
by water hyacinth. Considerable growth of this plant must be expected in lakes
supplied with river water. Lakes in the western part of the morass will become
clearer. Instead of floating water hyacinths submerged vegetation will dominate
the littoral zone. A vertical oxygen curve with total deficiency in the deepest
layers, which is characteristic of high-temperature waters, can be predicted.
The shrimpery, which at present is economically the most important activity
practised in the Lower Morass, will not be affected in those areas near the
rivers. However, during flooding periods shrimp are also caught outside the
rivers. Access to water in the flooded sections makes it possible for shrimp to
move away from the rivers. Creation of lakes, permanently or temporarily
connected with the rivers will offer possibilities for shrimp to spread to new,
productive littoral zones. The new littoral zone accessible for shrimp and
shrimpery after suggested mining will have a total area of 140 hectares. The
minimum increase in shrimp production and yield has been estimated at four times
the present (Karlsson & Leonardson 1984).
Mining also means creation of islands and other types of isolated biotopes which
it may be possible to protect efficiently against man and the mongoose (introduced
during British occupation). It is, therefore, anticipated that birdlife will
improve considerably. From an ecological and environmental point of view the
first goal must, of course, be to save the Lower Morass as a wetland. If plans
to drain the wetland for agricultural purposes were realized, this action would
constitute an ecological catastrophe and an economic disaster with long-term
effects as demonstrated in other comparable projects.
The economically feasible way to save the Lower Morass as a wetland is by the
mining of peat. In this manner, the multipurpose utilization of the area will be
safeguarded. No single way or any combined forms for utilization of an unmined
Lower Morass could compete economically with the combined peat mining/multipurpose
use. Ecologically this combination is also without competition because it would
be reliable in the long-term. The accomplishment of the eco-technical plans
would also mean creation of new jobs and an improved standard of living in a
region suffering from very high unemployment (Karlsson & Leonardson 1984).
The Negril Morass
In Negril Morass government efforts to stop production of Cannabis have resulted
in the saving of the last remnants of a wet forest with the endemic swamp
cabbage palm (Roystonea princeps). The southern part of the wetland, including
the palm forest, is now a national park. Furthermore, a modern wetland research
station has been built at the margin of the morass, close to those lakes, which
were created through peat extraction at the start (1981-1982) of the
Swedish-Jamaican environmental feasibility study of peat mining. In these lakes
the local development of ecosystems (Cronberg 1983, Enell 1984) in waters with
different depths, differently designed littoral zones, with and without islands,
etc., have also been investigated. Among other things the importance of open
water for the feeding and nesting of birds was demonstrated by the experimental
lakes. In the drained Negril Morass, which proved to be generally poorer in
birds than the Black River Lower Morass, water-birds were attracted to the
experimental lakes with their islands and shallow shores and nesting occurred
quickly after their construction (Björk 1983, Svensson 1983).
In Negril, a peat extraction project opens up unique possibilities for
ecological-technical cooperation in the design and management of an ecologically
diverse, sustainable wetland. The general appearance of the Negril Morass would
change from its present degraded form to an environmental asset, with a mosaic
of open water, islands and peninsulas. (Björk 1983, 1984, Karlsson & Leonardson
After redevelopment, the Negril and Black River Lower Morasses should be given
the status of national parks in an ecologically modern sense, i.e. optimally
utilized, managed and preserved. Parts of the Lower Morass should be granted
this status immediately to ensure protection in the same way as the swamp-forest
national park at Negril.
The necessity of a holistic view in time and space
In conservative types of environmental protection time factors are often
forgotten and ecosystems seen as static. As in other similar systems, conditions
in the Negril and Black River Morasses have changed considerably in the
long-term and at high speed recently. The "don't touch" ideology should
definitely not be applied here, but instead active design and management are
needed, provided there is a serious desire to preserve the areas as sustainable,
diverse, and useful wetlands. "In all cases of serious damage the need to
establish scientifically sound practices to restore productive capacity calls
for action: eco-redevelopment" (Brinck, Nilsson & Svedin 1988). Obviously, man
affects nature not only negatively, but can also make improvements and,
according to environmental and societal priorities, revitalize damaged
ecosystems to produce sustainable units.
Certain landscapes, like the Scandinavian meadows with pollard trees, are highly
esteemed and protected, though they were designed entirely by man. After
lowering of water levels in shallow lakes, many of the lakes pass through a
short, successional phase and are excellent biotopes for waterfowl during this
period. Through application of limnological principles and experiences, methods
to secure the prolongation of the favourable conditions in such ecosystems
became available (Björk 1985, 1988, 1990). "Management of the environment
involves both preventive measures as well as rehabilitative actions at reviving
damaged ecosystems. Prevention involves long-term protection schemes where
societal development and environmental goals are harmonized such as described in
the work of the Brundtland Commission" (Rosemarin & Svedin 1988).
In the case of the Negril and Black River Lower Morasses there is an urgent need
to revive the wetlands, and removal of peat is the only realistic way to
accomplish this. The commonly expressed claim that large-scale mining of peat is
impossible without destroying habitat and ecosystems is definitely not in
agreement with modern, constructive environmental management; especially in the
case of the damaged and endangered Jamaican Wetlands. A holistic view in time
and space is inevitable for planning for what the Brundtland Commission terms "sustainable
development". This commission provided the impulse for national aid
organizations to include environmental protection as a prerequisite for
assistance to developing countries.
Effects of predicted acceleration of sea-level rise (greenhouse effect)
The accelerated release of CO2 and other greenhouse gases into the atmosphere
is calculated to increase the global mean temperature by 1.5-5.5 oC during the
next century (Dickinson 1986). This global warming could be expected to cause a
significant acceleration in sea-level rise because of volume increase in
seawater and the melting of glaciers. Recently, it was concluded that the best
estimate of future sea-level rise by AD 2050 is 24-38 cm, corresponding to a
rise of 3-6 mm per year, which is 3-4 times greater than the global rates over
the past 100 years (Tooley 1989).
Generally speaking, the presumed increase in the rate of sea-level rise will
result in accelerated inundation of coastal lowland areas, and in erosion and
landward migration of sandy shorelines. The ability of coastal wetlands, such as
the Negril and Black River Lower Morasses, to sustain vertical growth and not to
disappear due to flooding and drowning, will depend on the balance between
organic production and peat formation and the rate of subsidence, combined with
sea-level rise. In the Negril Morass, upward peat growth during the period of
rapid sea-level rise in the early Holocene was able to keep pace with a rise of
3.8 mm per year (Digerfeldt and Hendry 1987). A sudden pulse of a probably still
higher rate of sea-level rise, resulting from the greenhouse effect, will
undoubtedly place stress on the wetland system.
In the Negril area, the narrow and low beach separating the coastal wetland from
the sea is probably very sensitive to erosion. The sandy beach would migrate
landwards and cover previously deposited peat. However, the risk for direct
erosion of large peat quantities with effects on the offshore environment must
also be great. So far the beaches have been protected by coral reefs.
In both areas, the seawater intrusion will increase and affect the wetland
environment. The areas east of the present Negril Morass, which were drained for
agricultural purposes in the late 1950s, but soon abandoned because of soil
subsidence, will probably be transformed to wetland again. The area of the Black
River Lower Morass will increase significantly as surrounding lowland will be
transformed into wetland.
In the scenario including an accelerated sea-level rise, the wetlands will
probably continue to develop as in the past, though in a more dynamic
succession. Some of the serious degradation problems caused by man would then be
solved automatically. However, also in the light of these prognoses, the plans
for optimum utilization including mining of still available peat are the most
realistic, both environmentally and socio economically.
The environmental feasibility study of peat mining in Jamaica, organization
The investigations have been carried out as a joint Swedish-Jamaican project
financed through Swedish and Jamaican governmental institutions, viz., the
Swedish Agency for International Technical and Economical Co-operation (Swed:
Beredningen för Internationellt Tekniskt Samarbete, BITS) and the Petroleum
Corporation of Jamaica (PCJ). The Swedish team has been headed by Professor Sven
Björk, Institute of Limnology, University of Lund, and the Jamaican team by Dr.
Barry Wade, Director, Environment and Special Projects, PCJ.
The authors express their sincere thanks to the Swedish Agency and to Dr. Barry
Wade and his co-workers at the PCJ for most stimulating, straightforward
collaboration. The profound concern for the environment and for solving
ecological problems demonstrated by PCJ is highly esteemed.
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