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61.
江锦祥  徐凤山 《台湾海峡》1992,11(4):291-293
帘蛤科一新种——扁平美女蛤Circe(Laevicirce)hongkongensis sp.nov.系于1988年采自香港大潭湾潮下带。新种的主要特征是两壳极扁平,铰合部宽阔,区别于本亚属的其他种。  相似文献   
62.
From 1980 to 1998, biofouling communities in Hong Kong waters, the Zhujiang RiverEstuary and the Mirs Bay were studied and a total of 610 samples. The samples were collected from vessels, buoys, piers and cages. Totally, 340 species (see Appendix I ) have been recorded and identified, six of which are new. At the same time, research on the biology of the cirripede, bryozoan, polychaete and mollusc communities were also conducted. Twenty-three related papers have been published. This review summarizes works in Hong Kong over past twenty years, and some unpublished data are also reported.  相似文献   
63.
香港/澳门近72年海平面变化曲线   总被引:8,自引:3,他引:5  
取1959年为接口,将澳门的前段记录(1925 ̄1958年)与香港的后段记录(1959 ̄1996年)连接起来,统一按香港海图基准面起算,可以得到最近72年(1925 ̄1958年)均一的海平面月均序列。海平面曲线反映海平面呈波动上升趋势,其中存在异常高海平面和异常低海平面。按香港和澳门的验潮资料,海平面上升速率为1.8±0.1mm/a。海滩岩的高程、地震活动、地形变化表明:香港和澳门地区的构造处于相  相似文献   
64.
1 Introduction Thelifecycleofhorseshoecrabsislengthywhencom paredtoothermarinearthropodssuchasbluecrabsandshrimpspecies (Sekiguchietal.,1988) .Thetwospecies,TachypleustridentatusandCarcinoscorpiusrotundicauda,knowntooccurinHongKongrequire ,respectively ,betweenthirteentofourteenandtentoelevenyearstomaturebeforedepartingtheirnurserybeachesfordeeperwaters (ChiuandMorton ,1999a ;Sekiguchietal.,1988) .Thelivingenvironmentofthenurserybeacheswheretheeggsarelaidandincu bated ,andfromwhichtheyoun…  相似文献   
65.
66.
The rapid development in the Hong Kong‐Pearl River Delta (PRD) city‐region has taken place alongside complicated cross‐border governance. The framework of time‐space envelopes (TSEs) is adopted for a study of cross‐border governance in Hong Kong, especially in the role of the state, that is, the Hong Kong government, in cross‐border urban governance. This article argues that tension‐ free regional integration has never existed due to a complex governance network. The shift from “cross‐border protectionism” to “cross‐border free trade zone” in Hong Kong's cross‐border urban governance since 2001 is a result of the rearticulation of the state cutting through the geoeconomic and geopolitical TSEs.  相似文献   
67.
考察香港经济发展的历史过程,文章将其房地产业的发展划分为起步、升温、繁荣与低迷4个阶段;分析了香港房地产业在经济中占据的地位、房地产的重点开发地区、主要开发类型等特点;探讨了影响房地产发展的经济因素、人口因素以及外部环境因素,并预测了房地产业未来的发展趋势:私人住宅和商业楼宇仍将是香港房地产业消费热点,环境优美的地区仍是投资热点地区,房产价格近期内难以上扬。  相似文献   
68.
Anthropogenic grasslands mixed with fern and shrubland, on scales from metres to kilometres, are widespread in tropical Southeast Asia, and especially in southern China and adjoining regions where harvesting for domestic fuel is a major factor in their maintenance. Baseline surveys in grassland and fernland in 1989–90 and resurveys in 2001 of three 6 × 20 m plots in Wong Chuk Yuen, Hong Kong, showed substantial change in species composition and total aboveground phytomass as a result of annual harvesting, with more pronounced change in the fernland. Under harvesting pressure, the species composition of the grassland changed considerably, though the proportions of the various life‐forms did not. Ischaemum spp. and Miscanthus floridulus increased whereas Themeda gigantea died out while the proportion of other grass species remained much the same. Under the same regime the species composition and life‐forms of the fernland changed markedly. The proportion of Dicranopteris fern dropped substantially, though still comprising a third of the phytomass by 2001. The shrub Melastoma survived harvesting. A firebreak cut in the fernland became grassy under annual harvesting and remained grassy six years after cutting ceased. The annual harvests from the growth‐years 1991–2000 showed a substantial though variable increase in total phytomass. Analyses relating harvested phytomass with various climatic parameters showed no significant correlations. Some possible reasons for this are suggested. Although annual harvesting was clearly sustainable over the ten years of observation, the question of continued sustainability on sites harvested for centuries, the situation in much of southern China and parts of upland mainland Southeast Asia, remains unresolved.  相似文献   
69.
K. T. Chau  J. E. Chan 《Landslides》2005,2(4):280-290
On the basis of 1,834 landslide data for Hong Kong Island (HKI), landslide susceptibility maps were generated using logistic regression and GIS. Regional bias of the landslide inventory is examined by dividing the whole HKI into a southern and a northern region, separated by an east-west trending water divide. It was found that the susceptibility map of southern HKI generated by using the southern data differs significantly from that generated by using northern data, and similar conclusion can be drawn for the northern HKI. Therefore, a susceptibility map of HKI was established based on regional data analysis, and it was found to reflect closely the spatial distributions of historical landslides. Elevation appears to be the most dominant factor in controlling landslide occurrence, and this probably reflects that human developments are concentrated at certain elevations on the island. Classification plot, goodness of fit, and occurrence ratio were used to examine the reliability of the proposed susceptibility map. The size of landslide susceptible zones varies depending on the data sets used, thus this demonstrates that the historical landslide data may be biased and affected by human activities and geological settings on a regional basis. Therefore, indiscriminate use of regional-biased data should be avoided.  相似文献   
70.
In this study, groundwater quality information collected in 1896 (well waters), 1980/1981 (piezometric and seepage samples) and 2002/2003 (seepage samples) in the regions centered by the Mid-Levels area, Hong Kong Island, was compared to illustrate how groundwater quality has changed over a century and the processes controlling it. As shown by saline ammonia and nitrate levels in the late nineteenth century, groundwater was severely polluted by widespread and obvious leakage from poorly designed wastewater collection systems, although groundwater was still a drinking water source for local residents. The extremely high residual chlorines in groundwater demonstrated that large doses of disinfection agents were added to wells at that time. In view of the decline in saline ammonia and nitrate levels, groundwater became less organically polluted in the 1980s probably due to significant improvement of the design of underground sewers. However, more leakage from sources such as salty flushing water and fresh water pipes emerged in the past few decades which added complexity to groundwater chemical systems. Some chemicals were used to identify possible locations of leakages. The temporal variations of the distribution of these chemicals over the area may shed light on the rate of leakage. Leakage from service pipes seems to have improved from the early 1980s to 2002/2003. However, the area is still suffering from widespread and small-scale leakage from service pipes. More efforts should be paid to control small leakages in the future. The findings will be instructive to various government organizations such as the Water Supplies Department and Drainage Services Department to identify possible locations of unobvious leakages in the area.  相似文献   
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