Resource information
Much of Hong Kong is currently undeveloped and consists of vegetated, relatively steep hillsides, which are considered to be natural terrain. However, in many of these areas there is evidence in old aerial photographs of man-made features, which for the last 30–40 years or so have been hidden by dense vegetation. Before the 1970s the vegetation was considerably less dense than today and much of the ground surface was bare and clearly apparent. Preliminary study of old aerial photographs indicates some 10 types of man-made features, including agricultural, military, mining, prospecting, and other activities. Some are fairly recent, but relatively surprising is the widespread evidence of old to ancient land management practices, particularly on the more remote, elevated steep terrain away from existing villages. These features include stone walls, stone structures and a variety of stone terraces and unsupported earthen step-form terraces, some of which may have their origins with pre-Chinese aboriginal hill tribes. Their distribution, nature and occurrence provide an insight into the history of human settlement in Hong Kong, which is generally unknown within the earth science and engineering communities. These man-made features occur over extensive areas, with many on steep slopes and in natural drainage lines, and with some stone walls and agricultural terraces in excess of 3 m in height. These features should be recognized during natural terrain landslide hazard assessments and other engineering geological and geotechnical studies.
