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Fung
Shui Forest, Montane Forest and Lowland Forest
The
WWF map has combined Woodland and Woodland/Plantation
Woodland to form one "Woodland" category
on the map. The area occupied by this merged category
and the SUSDEV 21 forest habitats (ie Fung Shui
Forest, Montane Forest and Lowland Forest) were
compared. The WWF "Woodland" occupied
10,062 ha and the SUSDEV 21 "Forest"
constituted 18,397 ha and an increase of 8,335
ha was obtained (Table 9.5b).
Mixed
Shrubland
The
area occupied by Tall Shrubland and Tall Shrubland
with Grass on the WWF map were combined and the
resulting value (ie 20,050 ha) was compared with
the area (16,478 ha) identified for Mixed Shrubland
under the SUSDEV 21 study. The value showed a
decrease of 17.8% (Table 9.5b).
Baeckia
Shrubland and Shrubby Grassland
The
Low Shrubland and Low Shrub with Grass habitats
categories identified under the WWF study were
combined to facilitate comparison with the combined
area figure obtained for Baeckia Shrubland and
Shrubby Grassland of the present baseline survey.
The WWF Low Shrub habitat occupied a total of
19,568 ha whereas for the combined Baeckia Shrubland
and Shrubby Grassland category, an area of 14,680
ha was identified, and this resulted in a decrease
of 4,888 ha in land cover (Table 9.5b).
Plantation
or Plantation/Mixed Forest
Plantation
Woodland mapped on the WWF map was compared with
the Plantation or Plantation/Mixed Forest category
identified under the SUSDEV 21 study. There were
4,830 ha of Plantation Woodland shown on the WWF
map but a much lower number of hectares (180 ha)
of Plantation or Plantation/Mixed Forest recorded
on the habitat map of the present study (Table
9.5b).
Grassland
There
was a total of 26,081 ha mapped for grassland
under the present study (SUSDEV 21) and a much
lower area of 17,726 ha was identified for the
habitat based on the WWF map data (ie sum of the
area mapped for Grass/Plantation Woodland, Grassland
and Grass/Bare Rock or Soil). An increase of about
47.1% was noted for this habitat category (Table
9.5b).
Natural
Vegetation Habitats
A
comparison was also made between the overall area
identified for the natural vegetation habitats
(including plantation) between the two maps. The
combined area of the natural vegetation habitats
defined for the WWF study (ie Woodland, Plantation
Woodland, Tall Shrubland, Tall Shrub with Grass,
Low Shrubland, Low Shrub with Grass and Grassland)
was 67,406 ha. The summed total of the natural
vegetation categories identified for the present
baseline survey (ie Fung Shui Forest, Montane
Forest, Lowland Forest, Mixed Shrubland, Baeckia
Shrubland, Shrubby Grassland and Grassland) was
75,816 ha which showed a 12.5% increase in area
when compared with the WWF value (Table 9.5a).
Freshwater/Brackish
Wetland
A
total of 325 ha of Other Wetland was mapped on
the WWF map but a much higher area was recorded
for the present baseline survey (1,030 ha) (Table
9.5b).
Mangrove
A
total of 276 ha of mangrove was shown on the WWF
map whereas for the present habitat map, a total
of 327 ha was identified. An increase in 18.5%
was calculated for this habitat (Table 9.4b).
Cultivation
As
both abandoned cultivation and active cultivation
were mapped under the same category Cultivation,
the area identified for the two cultivation types
under the WWF study was combined for comparison.
The WWF map shows 4,581 ha of cultivation whereas
for the present baseline survey, a total of 4,381
ha was mapped which result in 4.4% decrease in
cultivated land (Table 9.5b).
Bare
Rock or Soil
Data
from the WWF study showed that in 1989 there were
2,115 ha of bare rock or soil in Hong Kong. Comparison
of this data with the present survey data has
revealed a decrease of 675 ha (ie 31.9%) of habitat
area (Table 9.5b).
Quarry
There
has been an increase of 49.7% in the area of quarry
since 1989. The area of quarry identified on the
WWF map was 153 ha whereas for the SUSDEV 21 habitat
map, a total of 229 ha was mapped (Table 9.5b).
Rural
Industrial Storage/Containers
A
substantial increase (132.8%) of rural industrial
storage/container areas was detected based on
the habitat data comparison between the two Studies.
In 1989, an area of only 433 ha was identified
for the category whilst for the present map information,
a much higher area (1,008 ha) was recorded (Table
9.5b).
Other
The
Urban category defined under the WWF study included
buildings, development areas and landfill sites
and constituted a total area of 16,933 ha. To
facilitate comparison, the areas mapped under
the SUSDEV 21 study for the categories of Other
and Landfill were combined and a total area of
18,820 ha was obtained. The difference in the
two area figures, ie 1,887 ha, is equivalent to
11.1% increase in "urban/highly modified"
areas (Table 9.5a).
As
some of the habitat categories defined under the
present study are different from those classified
on the WWF map, no trend of changes can be determined.
These categories include:
As
the WWF study did not include intertidal habitats
for mapping, no information was available for
comparing the coastal and intertidal habitats,
ie Seagrass Bed, Intertidal Mudflat, Sandy Shore,
Rocky Shore and Artificial Rocky/Hard Shoreline.
While there is a category called "Inland
Water" on the WWF map and two watercourse
categories (ie Natural Watercourse and Modified
Watercourse) on the SUSDEV 21 habitat map, appropriate
comparison between the two maps on these categories
cannot be made unless specific information on
the type(s) of habitats identified under Inland
Water had been provided. As areas identified as
golf course or urban park were combined as one
category under the present baseline survey whereas
for the WWF study, golf course was identified
as a separate habitat category and no separate
mapping was conducted for urban park, comparison
is not possible for this category.
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