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91.
广东发现细裂玉凤花   总被引:1,自引:0,他引:1  
2007年9月,对广东省惠州市新墟镇白云嶂进行植物学考察时,在一个斜坡上的一片次生阔叶林的潮湿林缘,发现了兰科植物细裂玉凤花Habenaria leptoloba Benth。此植物的模式产地为香港,第一次采集时间为1857年,后来虽在香港仍有发现,但事隔150年后才在广东发现。  相似文献   
92.
香港大榄郊野公园的植物组成与植被数量分类   总被引:1,自引:0,他引:1  
通过对香港大榄郊野公园森林群落的样地调查,利用组平均法和除趋势对应分析两种方法,对样方进行聚类与排序分析。把35个样地划分为11个植被类型,森林群落可划分为台湾相思(Acacia confusa Merr.)林、红胶木(Lophostemon confertus(R.Br.)PeterG.Wilson ex J.T.Waterh.)林、木荷(Schima superba Gardner ex Champ.)林、柠檬桉(Eucalyptus citriodora Hook.)林、湿地松+鸭脚木(Pinus elliottii Engelm.+Schefflera octophylla(Lour.)Harms.)林、土沉香(Aquilaria sinensis(Lour.)Spreng.)林、毛叶桉(Eucalyptus torelliana F.Muell.)林;灌木群落分为山油柑+越南叶下珠(Acronychia pedunculata(L.)Miq.+Phyllanthus cochmchinensis(Lour.)Spreng.)矮树灌丛、豺皮樟+桃金娘(Litsea rotoundifolia(Nees)Hemsl.var.oblongifolia(Nees)C.K.Allen+Rhodomyrtus tomentosa(Alton)Hassk.)矮树灌丛、大头茶(Gordonia axillaris(Roxb.ex Ker Gawl.)D.Dietr.)矮树灌丛、桃金娘+芒萁(Rhodomyrtus tomentosa (Alton)Hassk.+Dicranopteris dichotoma(Thunb.)Bernh.)灌草丛。DCA排序结果反映海拔高度与各个森林群落的分布格局和物种组成关系不大,而环境湿度是影响森林群落物种组成的主要因素。多样性分析结果显示,台湾相思林和土沉香林多样性指数最高,说明台湾相思林逐渐向次生林演变,除了红胶木林和少数郁闭度低的台湾相思林中有强阳生性树种外,大部分人工林下植物以阳生性稍耐阴的树种为主。调查结果显示,大榄郊野公园植物生长条件东部优于西部,西部的物种丰富度和多样性指数较低,主要以人工林和灌丛为主,加上山火频繁发生,导致长期处于先锋阶段。  相似文献   
93.
Lui  T.H.  Lee  S.Y.  Sadovy  Y. 《Hydrobiologia》2002,468(1-3):193-211
The composition and spatial distribution patterns of the macrobenthic faunal assemblages of an 8-ha tidal impoundment operated as a traditional shrimp pond at the Mai Po Marshes Nature Reserve, Hong Kong, were studied in relation to temporal changes in local environmental conditions. Species richness, abundance and biomass of macrobenthos across 5 different sub-habitats (seaward, middle, and landward parts of open water unvegetated areas, and Phragmites- and Kandelia-dominated, vegetated areas) within the pond were examined bimonthly between January 1997 and January 1998. Grab samples were collected randomly within the sub-habitats. Key physical environmental parameters of the sampling sites were also measured. A total of 46 species of macrobenthos was recorded: 11 polychaetes, 11 molluscs, 13 crustaceans and 11 insects. Mean species density in the five sub-habitats ranged from 0 to 3907 indm–2, with mean biomass ranging from 0 to 96.9 gm–2. The macrobenthos showed spatial and temporal differences among the sub-habitats and across sampling times. Species abundances of Polychaeta, Mollusca and Crustacea were significantly higher in the three open water areas than in the two vegetated (Phragmites- and Kandelia-dominated) areas, with an inverse pattern for Insecta. There were no clear temporal patterns although abundance and biomass generally increased in the cooler months. Results of a canonical correspondence analysis suggest that macrobenthic species richness, abundance and biomass in the open areas were positively correlated with salinity, while water depth, dissolved oxygen and sediment organic matter content had little relationship with the macrobenthic assemblage parameters. Ordination by multi-dimensional scaling suggests that different habitats supported distinct macrobenthic assemblages. The macrobenthic assemblage in the tidal pond was less species rich but denser than those in the neighboring tidal mangrove and mudflat, suggesting that conversion of these areas into extensively managed tidal aquaculture ponds results in reduced species richness in tropical mangrove habitats.  相似文献   
94.
本研究在2017-2019年期间利用新型大型飞行阻隔器在香港8个样地(八仙岭、西贡、城门、马鞍山、大帽山、大榄、地塘仔、石壁)开展了甲虫采集,整理鉴定出11科15种罕见甲虫,其中包括中国新纪录属种3个,香港新纪录科1个,香港新纪录属7个,香港新纪录种5个。在此基础上,对飞行阻隔器在获取罕见甲虫标本方面的效能进行了评价,并给出了飞行阻隔器未来的改造建议与方向,探讨了飞行阻隔器在生物多样性调查中的应用潜力。  相似文献   
95.
KWOK Hon-Kai 《农业工程》2007,27(10):3993-4001
The changes in the bird community structure of the largest natural secondary forest of Hong Kong over 10 years were investigated. Densities of the 10 most abundant species in 1993–1995 and 2003–2005 were compared using t-test. All resident habitat generalists showed significant decline in densities. Two forest specialists showed significant increase in densities: one is native and the other is exotic species. The trend of changes in the forest bird community of Hong Kong is mainly related to the absence of nearby forests that could act as “source” of forest dependent species to colonize the local secondary forests, and the invasion of exotic species.  相似文献   
96.
介绍了恢复生态学常用的理论,并指出恢复生态学研究大多涉及植被生态系统恢复。植被恢复的目标就是要恢复植被的合理结构、功能和动态过程,从而为人类提供生态系统服务。植被恢复可以把区域的地带性植被生态系统作为参考生态系统,但目前的植被恢复工作绝大部分只是恢复了植被生态系统的部分组成、结构和功能。植被生态系统恢复研究主要从退化的原因与过程、恢复的过程与机理,以及从生境恢复、种群恢复、群落恢复、生态系统和景观恢复等不同尺度上的恢复开展。在介绍华南地区的植被生态系统现存问题的基础上,对华南地区开展的植被生态系统恢复,尤其是华南植物研究所(园)开展的植被生态系统恢复研究进行了介绍。最后,提出了华南地区植被生态系统恢复的方向及发展趋势。  相似文献   
97.
This article investigates the complex interplay between religion, gender and marginalization among a group of Pakistani schoolgirls in Hong Kong. It is found that the participants experience multiple marginalization and develop various strategies against disadvantageous positions. It is also found that, while the Pakistani girls attempt to extricate themselves from the gendered practices in their heritage culture and its customs that marginalize and confine women, they simultaneously seek to establish an Islamic or Muslim identity that differentiates them from local girls. It argues that, while mainstream culture has, to a certain extent, released Pakistani girls from the oppression and pressure of religion and customs, they have not been provided sufficient guidance to realize their dreams, making the release temporary and uncertain. The implications of the findings and directions for future research are discussed.  相似文献   
98.
杨山牡丹的核型分析   总被引:16,自引:0,他引:16  
本文首次报道了杨山牡丹的核型及银染间期细胞核仁数目。结果表明,银染核仁数最多为6个;核型简式为2n=2x=10=6m(3 SAT)+2 sm (1 SAT)+2 s t (2 SAT), 其中第1和第4对染色体短臂上具1个随体,第2和第5对染色体短臂上具1对随体。此外,对国产芍药属二倍体种的随体数目及其杂合性等问题进行了初步讨论。 Abstract:In the paper,the karyotype and silver staining of nucleolar numbers of P.ostii Hong et Zhang were reported for the first time.The results show that nucleolar numbers are six at the most and karyotype formula is 2n=2x=10=6m(3 SAT)+2sm(1 SAT)+2st(2 SAT)of P.ostii.There are one satellite on each short arms of the first and fourth chromosomes and two satellites on each short arms of the second and fifth ones respectiuely.In addition,the satellitic numbers and satellitic heterozygosity of diploid species of Paeonia in China are briefly discussed.  相似文献   
99.
George Walthew 《Hydrobiologia》1995,295(1-3):335-342
The distributions of mangal gastropod snails in Hong Kong were investigated by transect studies in nine mangals from around the coast. Fifty-one species of mangal associated were found, of which 25 were considered common. Gastropod faunas varied considerably between sites, both in terms of number of species and species composition. No one gastropod assemblage was found to be typical of the Hong Kong mangal. Local habitat differences were considered to have a major influence over species distributions, both within and between mangals. It is concluded that if species diversity is to be preserved then a representative sample of mangals needs protection.  相似文献   
100.
特大‘新红宝’西瓜的快速繁殖研究   总被引:5,自引:1,他引:4  
利用新红宝西瓜种子、茎段、茎尖及腋芽为外植体,接种子改良的MS培养基上。种子经常规消毒灭菌后,7—15d后可获得95%以上的健壮无菌苗.苗高3cm─5cm时即可用于有关实验。接种6d后,茎段两端切口处膨大,28—35d后出现愈伤组织,出愈率达到68%。接种5d后,茎尖明显长大。在本实验的激素组合中.35d后,茎尖周围均出现了不同数量的腋芽。最好的组合为改良的MS+2.5mg/LBA+IAA1mg/L,可使一个茎尖在35—42d后扩增为18─21个芽并逐渐长成无根苗。47d后,转入改良MS+NAA0.5mg/L培养基中.生根率达到94%以上。28d后,将苗移到田间,第一批移苗500株,成活438株,成活率达到87.6%。  相似文献   
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