Table
of Contents
10.2 Environmental
Legislation, Policies, Plans, Standards and Criteria
10.10 Environmental
Monitoring and Audit
10. Ecological
impacts
10.1 Introduction
10.2 Environmental
Legislation, Policies, Plans, Standards and Criteria
10.3 Assessment
Methodology
10.4 Baseline
Conditions
10.5 Evaluation
of Habitats
10.6 Impact
Identification
10.7 Impact
Evaluation
10.8 Tree
Survey
10.9 Mitigation
Measures
10.10 Residual
Impacts
10.11 Environmental
Monitoring and Audit
10.12 Conclusions
List
of Tables
Table 10‑1 Ecological Importance of Habitats with Study Area
Table 10‑2 Evaluation of Ecological
Impact
Table 10‑1 Ecological
Importance of Habitats with Study Area
Table 10‑2 Evaluation
of Ecological Impact
List
of Figures
Figure 10-1 Habitat Map of Study Area for Ecological
Impact Assessment (2 SHEETS)
Tree Survey Plan
List of Appendices
Appendix
10-A Tree Schedule
Appendix
10-B Conceptual Planting Plan
Appendix
10-AC Flora
Species Recorded at Different Habitats
10.1.1
This section presents the results of the
investigations into the potential environmental issues related to ecological
impacts during the construction and operational phases of the Tsuen Wan Road
Upgrading.
10.2.1
Annexes 8
and 16 of the Technical Memorandum on Environmental Impact Assessment
Process (EIAO-TM) issued under section 16 of the Environmental
Impact Assessment Ordinance (EIAO) set out the criteria and guidelines for
assessment of ecological impacts.
General and project-specific criteria should be considered in assessing
the potential ecological impacts associated with development projects Hong Kong
government legislation and guidelines relevant to the consideration of ecology
under this study include the following:
·
Wild Animals Protection Ordinance
(Cap. 170), which prohibits the disturbance, taking or removal of specified
wild animals, their nests and eggs;
·
Forests and Countryside Ordinance (Cap.96)
and Associated Forestry Regulations, which protect forests and rare plant
species;
·
Protection of Endangered Species of
Animals and Plants Ordinance (Cap. 586), provides
for the control and/or prohibition of trade in specified plants and animals;
·
Environmental Impact Assessment Ordinance
(Cap. 499) and associated Technical Memorandum on Environmental Impact
Assessment Process (EIAO-TM);
·
Town Planning Ordinance,
which provides for the designation and protection through the planning process
of Coastal Protection Areas, Sites of Special Scientific Interest, Green Belts,
Conservation Areas, Country Parks and other specified uses which promote
conservation or the protection of the environment; and
·
“Guidelines for Implementing the
Policy on Off-site Ecological Mitigation Measures” (PELB Technical Circular
1/97, Works Branch Technical Circular 4/97, dated 17 February 1997).
10.3.1
Construction and operation of the Project
has the potential to produce impacts on habitats in proximity to the site
boundary. The study area in the
assessment is defined as
500m from the Project Boundary and is shown in Figure 10-1.
10.3.2
Recent aerial photographs were used to
identify the land uses, habitat types and their distributions within the Study
Area. This was supplemented by field
inspections conducted during July 2007 to characterize the baseline conditions
of the ecological environment within the Study Area or the area likely to be
directly or indirectly impacted by the Project. Tree surveys of possibly affected areas were
carried out by Scott Wilson Ltd in January
2008, namely “Tree Survey Report”. Also, a field vegetation Survey
at the northern part the study area was undertaken with China-Hong Kong Ecology
Consultants Co. in November 2007 and a further vegetation survey
(supplementary) was carried out in August 2008.
10.3.3
The potential ecological impact arose
from the Project is assessed in broad terms following the guidelines in Annex
16 of the EIAO-TM, and the impact evaluated based on the criteria in Annex
8 of the EIAO-TM. The need for a detailed
Ecological Assessment has been assessed with reference to the flow chart
included in Appendix A to Annex 16 of the EIAO-TM.
10.4.1
The majority of the Study Area comprises
urban development which is of negligible ecological value. Some areas of disturbed semi-natural
habitats such as woodlands with fruit trees planted by villagers are present at
the northern end of the site, and other disturbed man-made habitats such as
Plantation Woodland and Village with orchard are present elsewhere along the
alignment.
10.4.2
The habitats have been generally
classified into the following categories, as shown in Figure 10-1.
10.4.3
Urban parks of recent origin are located
at Rivera Gardens and Chai Wan Kok Rest Gardens. The vegetation comprises planted species of low ecological value,
and some open areas for sports pitches etc.
10.4.4
Plantation
woodlands were mainlygenerally distributed on the northward of
Tuen Mun Road. Acacia confuse was the dominant species planted in the woodland. No
rare and protected species was recorded. The list of plantation woodland species is presented in Appendix 10-A.
10.4.5
Woodland is generally dispersedly distributed
at the northwest fringe of Chai Wan Kok and also the region between Tuen Mun Road and Belvedere Garden.
Trees such asof Macaranga tanarius and Bauhinia spp. were commonly recorded
within the woodland generally. However,
more fruit trees species such as Dimocarpus
longan was recorded at the woodland in upper catchment. These fruit trees were likely planted by
villagers. All recorded plant species are common species in Hong Kong. No
rare and protected species was recorded.
The list of woodland
species is presented in Appendix 10-A.
10.4.6
Shrubland was located on upper catchment
channel. The plants were generally 1.5
meter in height. In total, 432
species were recorded at the shrubland. The most abundant species found in the shrubland were Microstegium ciliatum and Miscanthus sinensis. These species are common
in Hong Kong and Nno protected and
rare species were found. The list of shrubs species is
presented in Appendix 10-AC.
10.4.7
Two patches of
agricultural lands were located at both sides of the Tuen Mun Road. These agriculture lands were well managed and no weeds were grown on
the field. Zingiber officinale was the general species
growing on the field during the course of survey. 24 species were recorded at the agriculture
land. No rare or protected plant
species were recorded. All species recorded in the agricultural lands were shown in Appendix 10-A.
10.4.8
Village houses
were distributed at the Pun Shan Tsuen and at the southern side of Tuen Mun road. Orchard trees and some small patches
of agriculture land were found scattered
near the village house. In total, 523
species were recorded within this type of habitat. Most of them were vegetables and fruit trees. However, some individuals of Camellia japonica were recorded at the
village and they were planted ornamental plants which are not protected under
the Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586).
No rare and protected plant species was
found. The list of species found in this habitat is presented
in Appendix 10-A.
10.4.9
A small stream course was
found near Adventist Hospitaladjacent to the agricultural land behind Belvedere Garden.
Currently, Tthe length of the stream was
currently a modified channel and was dry up
and covered with concrete and climbers.is about 100m (inside the study area), 1 to 1.5m width and has little water and
oOnly
8 flora species were recorded in the stream. Mikania micranthaClausena lansium
was the dominated common species found in at the stream embankment. No protected
and rare species were found. The list of species found in this habitat is
presented in Appendix 10-A. As the stream is far away from the construction
site, the impact of the construction works on the stream is negligible.
10.4.10
The urbanised area development consists
mainly of roads and residential areas. Trees were generally
planted at roadside and recreational area for landscape purpose. About 75% of the vegetations recorded within this habitat were
exotic species which were planted for landscaping purposes. Ficus microcarpa and Aleurites
moluccana were common species in this habitat. This habitat was highly disturbed in
nature with limited ecological interest. Species
such as Crinum asiaticum, Chrysalidocarpus
lutescens and Leucaena leucocephala are
found in the area. No rare or protected plant species were
recorded. The list of species recorded
in urbanized
area development is shown in Appendix 10-AC.
10.4.11 There
are no SSSI’s, nature reserves or Country Parks within the Study Area. The area of woodland and shrubland to the
north of Tsuen Wan Road at the northern end of the Study Area is designated as
Green Belt under Outline Zoning Plan.
10.5.1
Table
10-1 shows the evaluation of the ecological
importance of main habitats within the Study Area.
Table 10‑1 Ecological
Importance of Habitats with Study Area
|
Criteria |
Urban Park |
Plantation Woodland |
Woodland |
Shrubland |
Agricultural Land |
Village with |
Stream |
Urban |
|
Naturalness |
Man-made |
Man-made (post-1982) |
Semi-natural |
Natural |
Man-made |
Man-made |
|
Man-made |
|
Diversity |
Low |
Low |
Medium |
Medium |
Medium |
Medium |
Low |
Medium |
|
Rarity |
Commonly occurring throughout urban
areas |
Commonly occurring on planted slopes |
Commonly occurring on slopes and urban
fringes |
Commonly occurring on slopes and urban
fringes |
No
rare or protected species |
No rare species, artificially planted
Camellia japonica |
Common |
Mainly exotic
species which are highly disturbed in nature |
|
Recreatability |
High |
High |
High |
Moderate |
High |
High |
High |
High |
|
Fragmentation |
Highly
fragmented |
Not fragmented |
Fragmented |
Fragmented by semi-urban development |
Not fragmented |
Fragmented by squatter houses and other
semi-urban development |
Not fragmented |
Highly fragmented |
|
Ecological linkage |
No linkage to habitats of high value |
No linkage to habitats of high value |
No linkage to habitats of high value |
No linkage to habitats of high value |
Linkage to habitats of woodland and stream |
No linkage to habitats of high value |
No linkage to habitats of high value |
No linkage to habitats of high value |
|
Potential value |
Low |
Low |
Low |
Low |
Low |
Low |
Low |
Low |
|
Nursery/ Breeding ground |
Unlikely |
Unlikely |
Unlikely |
Unlikely |
Butterflies and amphibian |
Unlikely |
Unlikely |
Unlikely |
|
Age |
Recent |
Recent (post 1982) |
Well established but subject to regular
disturbance |
Well established but subject to regular
disturbance |
Recent |
Recent |
Recent |
Recent |
|
Abundance/ Richness of wildlife |
Low |
Low |
Low-to-moderate |
Low-to-moderate |
Low |
Low |
Low |
Low |
|
Ecological Importance |
Low |
Low |
Low |
|
Low |
Low |
Low |
Low |
10.6.1
The works will comprise the upgrading and
widening of the existing Tsuen Wan Road, including junction modification. The works will entail some felling of
roadside vegetation of
low / not
important ecological
value but will not require significant land take. Thus, the ecological impact to the roadside
vegetation is negligible.
10.1.1
There will be no
disturbance to the areas of plantation woodland, shrubland, woodland, agricultural land, stream and Vvillage with
orchard which form part of the Green Belt and open space at the northern end of the
site.
The site
works will require some tree felling and transplantation within the urbanised developmentarea and uUrban pPark,
including alongside Gin Drinkers Bay Restored Landfill. The locations of affected trees/palms are
shown in Figure
10-2Tree Survey Report - Drawing No. 01345/1601 (Annex
3 of Tree Survey Plan issued at January 2008). The affected trees including native and
exotic tree species have been identified in the tree Tree survey Survey reportReport.
10.1.1
Dominant native tree
species include: Albizia lebbek, Bauhinia
purpurea, Hibiscus tiliaceus, Macaranga
tanarius and Peltophorum pterocarpum. On the other hand, dominant exotic trees
species include: Acacia confusa, Casuarina
equisetifolia, Eucalyptus citriodora and Eucalyptus
robusta. No Old and
Valuable Trees (OVT) as set out in ETWB TCW No. 29/2004 was identified within
the study area.
10.6.2
A total of 460 447 trees
are proposed to be felled, 245 2454 trees are to be
transplanted and the remainder (516 nos.) are to be retained.
10.7.1
The predicted impacts on each of the
identified habitats are shown in Table
10-2.
Table 10‑2 Evaluation
of Ecological Impact
|
Criteria |
Urban Park |
Plantation
Woodland |
Woodland |
Shrubland |
Agricultural Land |
Village
with orchard |
Stream |
Urban |
|
Habitat quality |
Low |
Low |
Low |
Low |
Low |
Low |
Low |
Low |
|
Species |
No
species with important ecological value is affected |
No species affected |
No species affected |
No species affected |
No
species affected |
No species affected |
No species affected |
No
species with important ecological value is affected |
|
Size/Abundance |
No
direct impacts |
No direct impacts |
No direct impacts |
No direct impacts |
No
direct impacts |
No direct impacts |
No direct impacts |
No
direct impacts |
|
Duration |
|
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
|
|
Reversibility |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
|
Magnitude |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
|
Overall Impact |
Negligible
|
Negligible |
Negligible |
Negligible |
Negligible |
Negligible |
Negligible |
Negligible
|
10.1.1A tree
survey was carried out in 2008 by Scott Wilson Ltd. which identified all tree
and palms (with girth diameter exceeding 95DBH). Proposals for retention, transplantation or felling of trees were
put forward. A total of 447, 244 and 516
trees were scheduled for felling, transplanting and retaining respectively (refers to Appendix
10-A).
Compensatory planting schedule is outlined in the Tree Survey Report.
10.1.1Table 10-3 summarizes the numbers of
tree schedule for felling, transplanting and compensationretaining.
Table 10‑3 Numbers
of Tree Schedule for Felling, Transplanting and RetainingCompensation
|
|
|
|
|
|
|
|
10.8.1
The mitigation measures
include:As no species with
important ecological value is affected in the Project, insignificant ecological impact is expected. Hence, no mitigation measure is required for the ecological impact.
·retention of 516 trees,
·transplantation of a
total number of 244 trees
·landscape works including
447 compensatory trees following completion of the projectProject.
Compensatory planting is provided in the Tree Survey Report – Annex 4 of “CONCEPTUAL PLANTING PLAN” under the legend - PROPOSED AREA FOR COMENSATORY
PLANTING (refers to Appendix
10-B): .All transplanting trees and compensatory trees
(i.e. 691 trees) shall be planted within the Project site and properly
maintained during operation of the Project. Any of these trees damaged
during operation of the Project shall be replaced. Details of compensatory
planting such as detailed location and compensatory plant species will be
decided at the design stage. It is recommended, as stipulated in ETWB TC(W)
No.3/2006 Tree Preservation, that the implementation of compensatory
plant should not be less than 1:1 (i.e. not less than 447 nos. of trees in this
project) and the compensatory planting trees should be at least of “heavy
standard” type.
·The landscape works are
described in details in the Landscape and Visual Impacts section (Chapter 8) of this EIA report.
10.1.1Table 10-3 summarizes the numbers
of tree schedule for felling, transplanting and compensation.
Table 10‑3 Numbers
of Tree Schedule for Felling, Transplanting and Compensation
|
|
|
|
|
|
|
|
10.9.1
Following implementation
of the landscape mitigation measures as described in the Landscape and Visual
Impacts section of this EIA report, and cConsidering that no species with
important ecological value is affectedthe low ecological value
of the affected habitats, the overall residual ecological impacts
of the project are considered to be negligible.
10.10.1 No
specific environmental monitoring or audit provisions are required with respect
to ecological impacts.
10.11.1 Within
the project area there isare no
recognized sites of conservation importance, or
important habitats, and no species of conservation importance other
than a small planted population of Lagerstroemia Speciosa along
a roadside verge. Some tree felling and
transplantation will be required in areas of urban parkland or amenity
plantationand
development, but these will be mitigated by compensatory
planting
is identified.
10.11.2 With
reference to Appendix A of Annex 16 of the EIAO-TM:
·
The project does not lie within any
recognized sites of conservation importance (as identified in Note 1 of Appendix
A to Annex 16 of the EIAO-TM);
·
The project will not affect any important
habitats (as identified in Note 2 of Appendix A to Annex 16
of the EIAO-TM); and
·
The project will not affect habitats
supporting significant populations of species of conservation importance (as
identified in Note 3 of Appendix A to Annex 16 of the
EIAO-TM). Although a small number of Lagerstroemia
Speciosa will require felling, these species are amenity plantation in urban development and park and
cannot be considered as a significant population of wild flora.
10.11.3 Having regard to the
conditions above, the ecological impacts would be negligible in this project. Having
regarded to the
conditions above, the ecological impacts would be negligible in this Project.