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1.
Linocarpon species are reported from Pandanaceae in Australia, Brunei, Hong Kong, Nepal, New Zealand, Philippines, Seychelles, Thailand and Vanuatu. Linocarpon lammiae sp. nov. were collected on decaying leaves of Pandanus tectorius in Hong Kong. Linocarpon siamensis sp. nov. and L. suthepensis sp. nov. were collected from decaying leaves of P. penetrans in Thailand. These taxa are described, illustrated and compared with Linocarpon species with similar ascospore morphology and dimensions. Included are a synoptic table, which compares the new species to similar known species, and a dichotomous key to species of Linocarpon known from members of the Pandanaceae.  相似文献   

2.
Photoperiodic responses among populations ofXanthium strumarium L. in eastern Asia from Vladivostok, USSR, to Hong Kong and Taiwan include a wide range of adaptation. Among indigenous populations of thestrumarium morphological complex, responses range from near day neutrality (Vladivostok) to approximately a night length requirement of 9.5 hr (Hong Kong). Introduced populations in Japan include a night length requirement of 9.75 hr in theitalicum morphological complex and of 10.25–10.5 hr in thechinense morphological complex. The range of photoperiodic adaptation is nearly as wide as among populations of North America.  相似文献   

3.
The treatment and disposal of pig-waste in Hong Kong has received much attention in recent years but, following any of the presently used treatment processes, solids remain to be further stabilized. Vermicomposting is a waste stabilization technique which converts waste into potentially recyclable materials such as worm protein and worm casts. The earthworm, Pheretima asiatica, can stabilize most of the solids arising from the treatment of pig-waste, including raw pig manure, suggesting that vermicomposting has a high potential as a unit process in the management of pig-waste in Hong Kong.S.H. Wong is with the Environmental Protection Department, Hong Kong; and D.A. Griffiths is with the Department of Botany, University of Hong Kong, Hong Kong.  相似文献   

4.
Upon exposure to chilling conditions, the seagrass populations of Thalassia testudinum Banks ex König, Syringodium filiforme Kütz., and Halodule wrightii Aschers. showed various amounts of leaf and plant damage that correlated with their origin in the Gulf of Mexico-Caribbean. Populations of more tropical origin in the southern Gulf and Caribbean showed the most chill damage and those of the northern Gulf showed the least injury from the exposure to low temperatures. Of the three seagrasses, Halodule showed greatest chill tolerance, Syringodium showed the least tolerance and Thalassia was intermediate. The uptake of 14C by leaves following exposure to chilling temperatures showed quantitative differences that correlated with the amount of leaf damage in the various populations. No significant changes in the fatty acids in total lipid extracts were noted in the Texas seagrasses after chilling and, therefore, their resistance to low temperature damage did not relate to changes in saturation of fatty acids. Although the growing conditions slightly altered the severity of the chilling effects, the differentiation of response to chilling among the seagrass populations is based on inherited properties.  相似文献   

5.
为保护香港特有植物香港鹅耳枥,基于典型样地调查,对香港鹅耳枥所在群落进行了研究。结果表明,在225 m2的样地内,有维管植物37科66属68种。建群种为香港鹅耳枥,个体高度最高3 m,所在群落植株平均高度0.92 m,分层不明显。位于中国香港岛的香港鹅耳枥处于衰退状态,小个体极少。因此,建议采取就地保护和迁地保护措施,以重建种群。  相似文献   

6.
A thermotolerant -amylase was purified from Bacillus circulans S31 isolated from soil in Hong Kong. The purified enzyme has an M r of 64 kDa and was stable at 50°C and pH 7.0 for 30 min. Its K m for starch was 0.9 mg/ml with a V max of 0.3 mg/min. It was not activated by any metal ion although sulphydrys reagents were inhibitory.H.S. Kwan, K.H. So and K.Y. Chan are with the Department of Biology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong S.C. Cheng is with the Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic, Hung Hom, Hong Kong.  相似文献   

7.
The diverse ecological roles played by different rodent species mean that the loss of some species and superabundance of others could potentially influence a wide range of ecological processes. Hong Kong (22° N, 114° E), with seven million people in a land area of 1100 km2, could be considered a `worst case scenario' for the survival of mammalian diversity. Existing information on rodents in Hong Kong was compiled from previous published and unpublished studies, and additional trapping was conducted at 17 non-urban sites. The rodent fauna of modern Hong Kong consists of eight species of rats and mice (Bandicota indica, Mus caroli, M. musculus, Niviventer fulvescens, Rattus norvegicus, R. rattus, R. tanezumi, R. sikkimensis: Muridae), one porcupine (Hystrix brachyura: Hystricidae), and one recently introduced tree squirrel (Callosciurus erythraeus: Sciuridae). Six of the murids are urban or agricultural commensals, so only the porcupine and two murids, N. fulvescens and R. sikkimensis, are likely survivors of Hong Kong's pre-deforestation native rodent fauna. The two murids co-dominate in forest and shrubland, but can also move through grassland, which has probably enabled their survival through repeated cycles of fragmentation and regrowth. Additional forest rodents that may have inhabited Hong Kong in the past are tentatively identified from information on their recent distributions in the region. One possible ecological consequence of Hong Kong's depleted rodent fauna is a shift in the balance between seed predation and seed dispersal, in favor of the former.  相似文献   

8.
Reproduction and/or sperm structure was studied in 18 species belonging to five genera of Galeommatidae from Phuket Island, Andaman Sea, Thailand, and Hong Kong. Incubation of the ova occurs in the inner and outer demibranchs of both gills, and sperm is most probably transferred to the ctenidial brood chamber as masses of agglutinated and non-encapsulated spermatozoa. The smallest specimens are males, but change into the female sex and there is a strong indication that some of the species are alternate hermaphrodites. Dwarf males occur in one species (Galeomma layardi). The sperm of all 18 species studied are of the ent-aquasperm type with a more or less hemispherical acrosome that is tilted with respect to the long axis of the moderately elongated nucleus. It is suggested that this type of sperm affords the best autapomorphy for the family Galeommatidae.  相似文献   

9.
Summary Inland and sea cliff populations of bothAgrostis stolonifera L. andHolcus lanatus L. were subjected to soil NaCl treatments, of 100 and 200 mol m−3 NaCl, and tolerance examined using plant dry weight data. A parallel experiment subjected them to salt spray treatments of 2.5%, 5% and 10% NaCl in distilled water, and tolerance assessed from leaf damage. Both populations of each species were equally sensitive to soil NaCl. When subjected to salt spray the sea cliff populations however showed marked resistance to leaf damage. Soil salinity resistance and salt spray resistance thus appear to be independent characteristics in these two species.  相似文献   

10.
查阅馆藏植物标本,有3种茜草科植物:丹草(Hedyotis herbacea)、小耳草(H.pumila)和蕴璋耳草(Scleromitrion koanum)为香港新记录。这些资料为香港的生物多样性工作提供了基础数据。  相似文献   

11.

Background

In order to improve the health of the most vulnerable groups in society, the WHO called for research on the multiple and inter-linking factors shaping the social determinants of health (SDH). This paper analyses four key SDH (social cohesion, social inclusion, social empowerment and socioeconomic security) across six Asia-Pacific countries: Australia, Hong Kong, Japan, South Korea, Taiwan, and Thailand.

Methods

Population surveys were undertaken using a validated instrument in 2009-10, with sample sizes around 1000 in each country. The four SDH were analysed using multivariate binomial logistic regression to identify socio-demographic predictors in each country.

Results

Low socio-economic security was associated with low income in all six study countries and with poor subjective health in Japan, South Korea and Thailand and with being married or cohabiting in Australia and Hong Kong. Low social cohesion was associated with low income in all countries and with undertaking household duties in South Korea, Thailand and Taiwan. Low social inclusion was associated with low income in Australia, South Korea and Taiwan and with poor subjective health in Australia, Japan and South Korea. Older people had lower social inclusion in Taiwan (50-59 years) and Hong Kong (retired), younger people in Japan and South Korea (20-29 years in both countries) and younger and middle-aged people in Australia. Low social empowerment was associated with low income in Australia, Thailand and Taiwan, with being aged 60 years or over in Australia, Hong Kong and South Korea, and over 50 years in Thailand.

Conclusions

This paper provides baseline measures for identifying where and how policy should be altered to improve the SDH. Furthermore, these data can be used for future policy evaluation to identify whether changes in policy have indeed improved the SDH, particularly for marginalised and vulnerable populations.  相似文献   

12.
An Enterobacter cloacae strain, producing restriction enzyme EclHKI, was isolated from a decaying potato. The enzyme is an isoschizomer of Eam1105I, which recognizes and cleaves GACNNN!NNGTC. EclHKI was produced at high activity (4×104 U/g wet cells) and was purified from contaminants which interfere with restriction digestion by passing the cell lysate through DEAE-Sephacel and heparin columns. Activity was optimal at 37°C in a medium salt buffer.H.-Y. Chan, Y.-C. Chan and P.-C. Shaw are with the Department of Biochemistry, The Chinese University of Hong Kong, Hong Kong: K.-M. Kam is with the Institute of Pathology, Sai Ying Pun Jockey Club Clinic, Hong Kong.  相似文献   

13.
Plant communities in the continental tropics have suffered less from exotic plant invasions than their oceanic island counterparts. Most studies have focused on near-pristine communities. By contrast, we examine the resistance of semi-natural continental plant communities in Hong Kong, which have been suffering from chronic and massive human impacts. We compiled a list of all naturalized non-native species recorded in Hong Kong and then sampled the plant communities for exotic species along roadsides, a stream through semi-natural vegetation, and in semi-natural vegetation away from both roads and streams on Tai Mo Shan, Hong Kong’s highest peak (957 m). Similar surveys were repeated in other areas of Hong Kong. More than 162 naturalized exotic plant species have been recorded in Hong Kong. On Tai Mo Shan, 29 exotic species were recorded in roadside vegetation, with the diversity but not percentage cover declining significantly with altitude. Fifteen exotic species were found along the stream, including two not found along the roadside. Only six exotic species were found away from roads and streams, all in unshaded areas disturbed by feral cattle. In all surveys, no exotics were found in closed woody vegetation or in open areas without feral cattle, except for one species. The shade-tolerant tropical Asian tree Syzygium jambos was found invading along some streamsides without anthropogenic disturbance. Despite centuries of massive human impacts, exotic plant invasions in Hong Kong are still largely confined to habitats that suffer from chronic human disturbance. Feral cattle promote invasion where people are absent, but this problem still seems potentially reversible. Only Syzygium jambos is of possible current conservation concern.  相似文献   

14.
Mytilopsis sallei is one of a small number of tropical estuarine organisms known to have successfully invaded habitats outside their native range in the Caribbean. This bivalve now occurs in several major ports in East Asia, which suggests the transport of larvae and/or adults by vessels. However, little work has been done to determine transfer pathways because direct evidence is difficult to obtain. Here we test whether there is sufficient genetic variability in a mitochondrial marker of established Asian populations of M. sallei to allow for future reconstruction of invasion history. We sampled a 376-base-pair fragment of the mitochondrial cytochrome oxidase I (COI) of M. sallei for 254 individuals representing 11 populations from Singapore, India, Hong Kong and Taiwan. We found high variability with 24 positions distinguishing 15 haplotypes. Haplotype diversity ranged between 0.6 and 0.8 in eight Singapore populations, and an analysis of molecular variance showed that there was no significant genetic segregation in these populations. Observed haplotype diversity was also high in a population from Visakhapatnam, India, but was slightly lower in samples from Taiwan and Hong Kong. Preliminary data also indicate that Singapore, India, Hong Kong, and Taiwan populations may have different dominant haplotypes. These results suggest that there is sufficient genetic variability to use mitochondrial markers for reconstructing the invasion history of Mytilopsis sallei, when larger sample sizes become available.  相似文献   

15.
Eleven of 16 samples of rice on sale in rice shops and supermarkets in Hong Kong contained Bacillus cereus. Although B. cereus counts did not exceed 100 bacteria/g in most of the positive samples, a sample of Thai red rice and a poor quality rice originating from China contained between 300 to 1000 cells/g and 104 to 2×105 cells/g, respectively. Nine strains produced an enterotoxin responsible for the diarrhoeal-type B. cereus food poisoning and seven of these strains also produced a haemolysin (haemolysin BL), a dermonecrotic vascular permeability factor which may be a virulence determinant in diarrhoeal illness caused by this bacterium.P.K. Lee and J.A. Buswell are with the Department of Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong; K. Shinagawa is with the Department of Veterinary Medicine, Iwate University, Iwate, Japan.  相似文献   

16.
Mitochondrial DNA D-loop (control) region (426-bp) was used to infer the genetic structure of Spanish mackerel (Scomberomorus commerson) from populations in Southeast Asia (Brunei, East and West Malaysia, Philippines, Thailand, Singapore, and China) and northern Australia (including western Timor). An east–west division along Wallace’s Line was strongly supported by a significant AMOVA, with 43% of the total sequence variation partitioned among groups of populations. Phylogenetic and network analyses supported two clades: clade A and clade B. Members of clade A were found in Southeast Asia and northern Australia, but not in locations to the west (Gulf of Thailand) or north (China). Clade B was found exclusively in Southeast Asia. Genetic division along Wallace’s Line suggests that co-management of S. commerson populations for future sustainability may not be necessary between Southeast Asian nations and Australia, however all countries should share the task of management of the species in Southeast Asia equally. More detailed genetic studies of S. commerson populations in the region are warranted.  相似文献   

17.
To understand the molecular events of ovarian development in penaeid shrimp, RNA arbitrarily primed polymerase chain reaction (RAP-PCR) was used to identify differentially expressed genes during ovarian maturation in Metapenaeus ensis. From a screening of 700 clones in a cDNA library of the shrimp ovary by the products of RAP-PCR of different maturation stages, 91 fragments with differentially expressed pattern as revealed by dot-blot hybridization were isolated and sequenced. Forty-two of these fragments show significant sequence similarity to known gene products and the differentially expressed pattern of 10 putative genes were further characterized via Northern hybridization. Putative glyceraldehyde–3–phosphate dehydrogenase and arginine kinase are related to provision of energy for active cellular function in oocyte development. Translationally controlled tumor protein, actin, and keratin are related to the organization of cytoskeleton to accomplish growth and development of oocytes. High mobility group protein DSP1, heat shock protein 70, and nucleoside diphosphate kinase may act as repressors before the onset of ovarian maturation. Peptidyl-prolyl cis-trans isomerase and glutathione peroxidase are related to the stabilization of proteins and oocytes. This study provides new insights on the molecular events in the ovarian development in the shrimp. Present addresses: T.S. Lo, Department of Applied Science, Hong Kong Institute of Vocational Education, Chai Wan, Hong Kong, China J.L.Y. Mong, Department of Biochemistry, The Chinese University of Hong Kong, Shatin, Hong Kong, China Q.W.L. Wong, Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong, China  相似文献   

18.
Both the length of the growing season and the intensity of herbivory often vary along climatic gradients, which may result in divergent selection on plant phenology, and on resistance and tolerance to herbivory. In Sweden, the length of the growing season and the number of insect herbivore species feeding on the perennial herb Lythrum salicaria decrease from south to north. Previous common‐garden experiments have shown that northern L. salicaria populations develop aboveground shoots earlier in the summer and finish growth before southern populations do. We tested the hypotheses that resistance and tolerance to damage vary with latitude in L. salicaria and are positively related to the intensity of herbivory in natural populations. We quantified resistance and tolerance of populations sampled along a latitudinal gradient by scoring damage from natural herbivores and fitness in a common‐garden experiment in the field and by documenting oviposition and feeding preference by specialist leaf beetles in a glasshouse experiment. Plant resistance decreased with latitude of origin, whereas plant tolerance increased. Oviposition and feeding preference in the glasshouse and leaf damage in the common‐garden experiment were negatively related to damage in the source populations. The latitudinal variation in resistance was thus consistent with reduced selection from herbivores towards the northern range margin of L. salicaria. Variation in tolerance may be related to differences in the timing of damage in relation to the seasonal pattern of plant growth, as northern genotypes have developed further than southern have when herbivores emerge in early summer.  相似文献   

19.
Abstract

Increased awareness of the value of marine resources and their fragility and/or limits is fostering a consideration of regional marine arrangements when states in physical marine regions perceive that global standards and regimes may not adequately address their special circumstances. The semi‐enclosed South China Sea appears to be a logical site for regional approaches to certain transnational problems of common marine resource use or protection. Political entities include the Westem‐oriented ASEAN block‐Thailand, Malaysia, Singapore, Indonesia, and the Philippines; the socialist states‐China, Vietnam, Kampuchea, and land‐locked Laos; politically‐isolated Taiwan, the British dependencies of Hong Kong and Brunei, and the Portuguese colony of Macau. Each political entity's predilection to participate in regional marine arrangements is determined by integrating perceived advantages and disadvantages to national marine interest, approximated by such measures as marine accessibility, dependence, investment and control, with the perceived importance of politically integrative and divisive factors.  相似文献   

20.
To estimate genetic structure of a soldier-producing aphid, Pseudoregma bambucicola, samples from natural populations throughout southeastern Asia were analyzed by a DNA fingerprinting technique. We unexpectedly found that P. bambucicola comprises two geographic groups, the northern group and the southern group, which are genetically distinct from each other but morphologically almost indistinguishable. Molecular phylogenetic and statistical analyses based on mitochondrial ribosomal DNA sequences demonstrated that the northern and southern groups of P. bambucicola are not closely related but constitute distinct lineages in the genus Pseudoregma. Detailed morphological reexamination revealed that the two groups could be distinguished by the number of setae on the 8th abdominal tergite of 1st instar nymphs and soldiers. From these results, it was suggested that P. bambucicola should be divided into two species. The northern group from Japan, Taiwan, Hong Kong, and northern Vietnam retains the name P. bambucicola, whereas we suggest that the name P. carolinensis (R. Takahashi, 1941, Tenthredo 3, 208–220) should be used for the southern group from Thailand, Malay Peninsula, Java, Irian Jaya, and Micronesia. The morphological resemblance between P. bambucicola and P. carolinensis might be due to shared ancestral characters of the genus Pseudoregma.  相似文献   

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