SECTION 4 ECOLOGICAL RESOURCES CAPITAL STOCK
4.3 Impacts and Resource Constraints for Terrestrial and Marine Habitats and Species
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| 4.3.2.5 |
As explained in Paragraph 4.2.1.748, direct comparison between the WWF study and the SUSDEV 21 Habitat Mapping Baseline Survey in an attempt to identify trends in the loss of terrestrial habitats is not feasible due to the major differences in the methodology and habitat category definitions employed by the two studies (for details, see Section 9.5 of Habitat Mapping Final Report). Therefore further discussion on trends of terrestrial habitat loss in Hong Kong based on the comparison between results of the two studies is not available. |
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| 4.3.2.6 |
In addition to valuable habitats, Hong Kong hosts a wide variety of species, many of which are listed as priorities for international or local conservation efforts (see Section 4.2). Some of these species, such as Romer's Tree Frog (Philautus romeri), are endemic species confined to a limited range of habitats within Hong Kong, whereas others, such as the Black-faced Spoonbill (Platalea minor), range over a vast territory (ie Korea to Vietnam) but have habitat requirements that are met by only a few remaining sites in the region. Ongoing data analysis by HKU Biodiversity Survey researchers will illustrate which terrestrial habitats support the greatest number of species, as well as which areas support species that are not found in other areas of Hong Kong. Locations which are identified as valuable but which are not currently protected will thus be highlighted. |
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| 4.3.2.7 |
The most obvious impact on terrestrial habitats and species is the development of land and associated urbanisation which can result in large scale habitat loss, fragmentation or alteration. For example, it has been reported that due to large-scale habitat loss, numbers of amphibians, particularly those species which breed in marshes, pools and wet fields are exhibiting population declines (Lau 1995). The expansion of development into areas which are currently in a natural or semi-natural state is discussed in Paragraphs 3.2.2.2 - 3.2.2.7 - Land Use and Land Supply and Paragraph 3.3.3.2 - Agriculture and Fisheries. In addition to considering the impacts of development in Hong Kong on local terrestrial habitats and species, it is also important to consider the regional context of development and ecological conservation. The Pearl River Delta formerly contained vast areas of wetlands, fishpond, mangroves, mudflats and agricultural lands. However, in the Futian (northern Deep Bay) area alone it is estimated that the number of fishponds was halved between 1987 and 1993 due to filling for development of the Shenzhen Special Economic Zone (Aspinwall 1998). The loss of agricultural land in the Pearl River Delta is estimated at 1% per year since 1979 (Chau 1994) and intertidal areas have been decimated by large-scale reclamations such that little natural intertidal habitat remains. The effects of cross-boundary development in combination with local development pressures exert a strong force on the quality and quantity of remaining ecologically valuable habitat in Hong Kong. |
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| 4.3.2.8 |
Another major cause of habitat damage, and thus loss of biodiversity, in Hong Kong is the frequency and magnitude of hill fires. Grassland habitats in many areas of the New Territories are the result of years of persistent and extensive hill fires. Fires prevent or arrest the natural ecological succession of grasslands to shrublands to forests, result in the loss of species sensitive to fire, and degrade and destabilise soils. During the autumn Chung Yeung and spring Ching Ming festivals, fires are often started as part of grave sweeping activities and spread out of control. Fires may also be started by farmers wishing to clear unwanted vegetation and are a particular hazard in the dry season, or as a result of carelessness or deliberate vandalism. Between 1988 and 1998 there were 1,480 fires inside country parks which affected 15% of Hong Kong's total land area and over 800,000 trees, many of which had been planted as part of local reforestation initiatives. In Green Belt areas, which are potentially more susceptible to fires since they are not actively managed, the Territory Development Department report that around 500,000 tree seedlings planted in these areas were burnt through hill fires in 1999. The fire damage to trees in country parks in the last 10 years has been estimated to be $15 million (SCMP 1999b). Recent statistics show a decrease in the number of fires in Country Parks. In the 1997/98 fire season (ie September 15, 1997 to April 30, 1998), there were 54 fire outbreaks within or adjacent to country parks. Although this is the lowest figure for 20 years, it is attributed mainly to the high rainfall during the 1997/98 fire season. |
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