Similarly, there is also a lack of strategy for the management of land in the urban fringe such as Green Belt areas where recreational activities are taking place on an informal and unmanaged basis which may threaten the ecological and landscape value of such areas. Whilst such areas play an important role in containing development and providing an attractive 'green' edge to urban areas, their proximity to dense areas of population inevitably results in a demand for other uses of the land, such as recreation. Whilst Green Belt areas denote a presumption against development, there is no active landscape management, and it appears that a co-ordinated policy and strategy is required to manage both the land use demands and the natural capital of the resource.

These conflicts and pressures will continue to test the strength of protection of conservation areas. It is therefore essential to value the true worth of protected areas, through scientific research and public education, and to ensure that all critically important areas are adequately protected under the existing planning and policy frameworks. Ultimately, however, the stock of land supply for development cannot be sustained indefinitely, and alternatives to continued development of natural areas in the SAR will need to be identified.

Terrestrial Ecological Resources - Issues and Trends

• Hong Kong's terrestrial habitats consist of a wide variety of ecological communities which host a surprisingly diverse array of mammals, birds, amphibians, reptiles, fishes, invertebrates and plants.

• Grasslands, lowland forests and mixed shrublands are the most extensive habitat types, comprising about 23%, 16% and 15% respectively of the total terrestrial area of Hong Kong.

• Environmental Baseline Survey on Terrestrial Habitat Mapping and Ranking based on Conservation Value for the SUSDEV 21 Study has identified that the most ecologically important terrestrial habitats in Hong Kong are mainly composed of forest and shrubland habitats (including fung shui forest, montane and lowland forests and mixed shrubland), comprising almost 90% of the total area identified as of high ecological value. Other habitats including inland water (freshwater/brackish wetland and natural watercourse) and coastal habitats (including mangrove, intertidal mudflat, seagrass bed, sandy shore and rocky shore) cover less than 4% of the total land area of Hong Kong. Many of the wetlands surveyed have been subject to degradation from pollution and infilling for development purposes and several authors have reported on the decline in coastal habitats such as mangrove and seagrass beds in recent years.

• A number of important terrestrial species found in Hong Kong are under threat locally or globally including the Black-faced Spoonbill which winters at Mai Po Marsh, several species of freshwater fish as well as some amphibians, reptiles and larger mammals.

• Overall the terrestrial ecological resource is under threat from physical clearing for new development, increased disturbance from development encroachment, pollution pressures (eg in Deep Bay on the Mai Po Marsh Ramsar Site), and other effects such as hill fires and introduction of exotic species. Many ecologically diverse habitats such as wetlands occur in low lying areas which are particularly vulnerable to development. Whilst a network of designations exists in Hong Kong, in part to protect areas of nature conservation importance, the coverage afforded is patchy and a number of areas of important habitat remain unprotected from development.

• Future sustainability of the terrestrial ecological resource will require protection and management of remaining valuable habitat through implementation of an explicit conservation policy including a comprehensive system of ecological designations. In addition, the effects of pollution on threatened species needs to be better understood and the management of such species should be co-ordinated on a regional basis.

Marine Ecological Resources - Issues and Trends

• Hong Kong's marine habitats can be classified as hard bottom and soft bottom seabed habitats. Hard bottom habitat typically occurs close to the shore in the form of areas of rocky coast and, particularly in eastern waters, hard corals. Soft bottom habitat covers the majority of Hong Kong's seabed and usually comprises a mixture of sand and mud.
• Several areas of importance for marine biodiversity have been protected through designation of Marine Parks at Hoi Ha Wan, Yan Chau Tong and Sha Chau and Lung Kwu Chau and a Marine Reserve at Cape d'Aguilar. Further designations are currently under consideration.
• The SUSDEV 21 study has classified areas considered to be of particular importance for marine ecological natural capital stock as comprising: (1) areas which support the highest known marine biodiversity values, including designated and proposed marine parks and reserves; (2) areas which are documented to function as important marine spawning, nursery or key foraging habitats which have been identified by the AFCD study on Fisheries Resources and Fishing Operations in Hong Kong Waters; and (3) areas which contain marine habitats that are regionally rare or threatened or provide documented critical habitat for rare species.
• Marine habitats and species are particularly under pressure from reclamation and dredging, severe fishing pressure and disturbance and inputs of pollutants such as untreated effluent and sewage.
• Maintenance of the marine ecological resource in Hong Kong will require adequate protection of remaining valuable habitat, effective implementation of the proposed fisheries management strategy and continued control of pollution to the marine environment. Management of threatened species should also be co-ordinated on a regional basis.