This section presents a review of those elements of the capital stock which have particular value as natural resources. For the purposes of this report, natural resources have been defined as harvestable products or useable assets which are derived from naturally occurring or human managed environmental features. This section assesses the quality and quantity of natural resources existing within Hong Kong in terms of five categories:

• land use and land supply;
• agriculture and fisheries;
• freshwater resources;
• minerals, aggregates and energy resources; and
• waste arisings and disposal.

Natural resources capital stock is measured under several of the sustainability indicators defined by this Study. These indicators track the area of countryside, the volume of freshwater produced locally, the volume of freshwater supplied (ie a surrogate for volume used), energy consumption, and the size of terrestrial and marine areas which are managed for conservation (ie a type of land use). Two other indicators, waste generation and landfill capacity, are also considered to be relevant to natural resource issues since waste is a by-product of society's usage of raw materials. The volume of waste generated in Hong Kong reflects the way in which Hong Kong uses natural resources, albeit primarily derived from outside of the SAR, and the capacity of remaining landfills indicates how the usage of the raw materials affects the natural resource capital stock of land resources available to accommodate waste disposal.

In many cases, there are strong linkages between the stock of natural resources and the stocks of ecological resources, assimilative capacity resources and heritage resources. For example, many of the land use designations in Hong Kong preserve land in a natural or nearly natural form (eg Country Parks, Water Gathering Grounds) which then serve as valuable ecological habitats for key species. Similarly, the level and process by which natural resources such as freshwater and energy are used, and the amount of waste generated, determine the level of pollutants released to the environment. In this way, exploitation of the natural resources capital stock is directly relevant to the natural capital stock of assimilative capacity. Heritage resources, both recognised and potential, are strongly influenced by development pressures which are in turn a function of the land use policies being pursued. These linkages are addressed both in this section and in the following sections pertaining to Ecological Resources (Section 4), Assimilative Capacity (Section 5) and Heritage Resources (Section 6). The relationship between natural resource capital stock and the scientific, existence, landscape and recreational value of Hong Kong's resources is explored in Section 7.

Hong Kong has a total land area of 1,094.1 km2 which includes 59.3 km2 of land reclaimed from the sea since 1887 (WWF 1999). The availability of land in Hong Kong for development, transport, recreation, conservation and so on is extremely limited by topographical factors and existing land uses which have progressively occupied most of the developable land in the metropolitan areas. Whilst 53% of the territory has an average elevation of less than 100m, only 25% of the land has a gradient of less than 50 The remaining area is characterised with 29% at grades of 30?or more.

The suitability of land for development in Hong Kong has been classified into four Geotechnical Land Use Map (GLUM) categories, of which classes I and II are considered to have moderate to high potential for development. In 1989 when the Geotechnical Area Studies Programme (GASP) was published, 41% of the land area of Hong Kong fell into these two classes (ie 44,837 ha in 1989), although over 35% of this area (ca 15,700 ha) was within Country Parks where development is controlled (GCO 1989). A further 29% of the area (ca 13,000 ha) was already developed or under construction. The resultant land area suitable for development in these two land use classes outside of Country Parks was approximately 16,000 ha which represents 35% of the land in GLUM categories I and II and 14.5% of the total land area of Hong Kong. Given recent estimates that the built up land area of Hong Kong has more than doubled in the last 30 years (WWF 1999), it is likely that the percentage of land with development potential will have dropped considerably below previous estimates. Another factor in this reduction is the expansion of the Country Park system, notably an addition of 123 ha in the Sai Kung West Country Park in 1996, Lung Fu Shan Country Park which was designated in 1998 and covers 47 ha, and a proposal for the addition of approximately 2,000 ha in the North Lantau Country Park, scheduled for gazettal in September 2000.