海南部分地区两栖动物的调查

于2005年2月至3月调查r海南岛的部分地区两栖动物,主要集中在戈枕、湾岭和吊罗山,共计采集到13种标本,分隶4科7属。     

The cause of mollusk decline on the Ogasawara Islands

Decline of land snails on the Ogasawara Islands was studied. In Hahajima, major alien predators such as Euglandina rosea and Platydemus manokwari are not present, but some small endemic snails, for example, Hirasea spp. and Ogasawarana spp., are already rare and more common endemic snails, for example, Mandarina spp., are also declining in the northern mountains. The decline cannot be directly explained by forest deforestation and by its subsequent regeneration. Three species of flatworms were found to eat small snails under captive conditions. The distribution of these flatworms is restricted to the northern mountains of Hahajima where Mandarina is declining and its survival is low. These predators are plausible candidates as a cause of the decline of the endemic snails.     

海南石梅湾青皮林最小取样面积与物种多样性研究

石梅湾海岸青皮(Vatica hainanensis)林是海南独特的雨林群落之一。本文选用8种“种-面积渐近线”对该群落的最小取样面积进行了拟合研究。结果表明,其中5条曲线的R^2大于0．97,拟合状况很好,但所得出的最小取样面积各不相同。进一步经过“重要值-面积曲线”的群落特征分析,确认群落的最小取样面积只有800m^2。石梅湾青皮林最小取样面积比海南其他类型雨林、滇南热带雨林、东南亚热带雨林以及非洲雨林都要小。通过对1000m^2样地的物种多样性分析,结果表明：在垂直结构上,石梅湾青皮林B层乔木的Gleason指数大于A层乔木,和海南山地雨林的情况不同。海岸青皮林为物种多样性不高的单优林,群落的物种多样性、均匀度远小于海南其他类型的山地雨林与混合青皮林;在海岸青皮林群落内,青皮的相对密度、相对优势度、重要值大大高于其他物种。此研究表明：海南热带雨林同样存在物种多样性不高、单优特征显著的顶极群落;海南海岸青皮林是迄今为止热带雨林取样面积最小的森林类型。     

The control of the development of a marine benthic community by predation on recruits

Recruitment is an important process in regulating many marine benthic communities and many studies have examined factors controlling the dispersal and distribution of larval immigrants. However, benthic species also have early post-settlement life-stages that are dramatically different from adult and larval stages. Predation on these stages potentially impacts measured recruitment and the benthic populations and communities that ultimately develop.We examined the consequences of post-settlement predation on 1-day-old to 1-month-old recruits of sessile invertebrates at two field sites in southern New England. One site (Breakwater) was in a protected area with few predators and the other (Pine Island) was <1 km away in an open coast area with three different predator guilds: small and large invertebrates and fish. The Breakwater site had been dominated for >10 years by colonial and solitary ascidians. These species were absent from the Pine Island site which was dominated by bryozoans. Our goal was to examine whether post-settlement predation influenced the development and subsequent structure of the epifaunal community.Here we examine long-term changes in community development resulting from post-settlement predation, and contrast these results to those of earlier experiments examining the reductions in observed recruitment by post-settlement predation. Our first long-term experiment examined natural community development at the two sites and whether transplanted communities changed when exposed to the different levels of predation at these sites. The communities that developed at both sites were consistently different from each other and similar to resident communities at their respective sites. On panels transplanted from the Breakwater to Pine Island, solitary ascidians and the colonial ascidian, Botryllus schlosseri, suffered high mortalities on both caged and uncaged treatments, indicative of predation by small predators that could enter cages. Some solitary ascidians did survive inside cages and the colonial ascidian, Botrylloides violaceus, became dominant on all transplanted treatments. On panels transplanted from Pine Island to the Breakwater, ascidians invaded and dominated all treatments except those that were originally caged at Pine Island.In the second long-term experiment, natural communities were allowed to develop on panels exposed at the Breakwater for 1, 2, 3, and 4 weeks. Each set was transplanted to three treatments at Pine Island: open uncaged pilings, caged pilings to exclude fish and large invertebrates, and racks suspended above the bottom to exclude all predators. When 1-week-old communities were transplanted, after 2-3 weeks only bryozoans were found on the open and caged pilings, while colonial ascidians dominated the suspended rack treatment. When older 2-week-old communities were transplanted, colonial ascidians also became dominant in the caged piling treatment and when 3- and 4-week-old communities were transplanted colonial ascidians dominated all three treatments. Solitary ascidians were never abundant on open pilings exposed to fish and large benthic invertebrate predators.Post-settlement predator-prey interactions involved newly settled and juvenile life-stages of a variety of prey species and many invertebrate and vertebrate predator species. The effects of these interactions on recruitment did result in differences in the development and eventual species composition of the communities, even though predators had little if any effect on the adults of the prey species.     

海南岛霸王岭热带山地雨林群落结构及树种多样性特征的研究

 以海南岛霸王岭自然保护区1 hm2老龄原始林样地的调查材料为基础,分析了热带山地雨林群落的组成、高度结构、径级结构及有关的树种多样性特征。结果表明：霸王岭热带山地雨林树种较丰富,物种多样性指数较高。树种数和树木的密度都随高度级、径级的增加而呈负指数或负幂函数递减;热带山地雨林不同高度级、不同径级和不同小样方斑块内的树种数都与树木密度呈显著的正相关关系。热带山地雨林经过自然的演替达到老龄顶极群落后,最后进入主林层的只是少部分树种的少数个体。     

Apparent decoupling of prey recognition ability with prey availability in an insular snake population

Numerous studies on the feeding behavior of snakes have reported the consistency of tongue-flick responses with their natural diets. For representatives of widely distributed, dietary generalist species from particular localities, we can expect that their tongue-flick responses to potential prey unavailable in their original habitats have been reduced whereas those to prey common in the habitats have been enhanced. To test this hypothesis, intraspecific variation in tongue-flick responses to prey chemicals was examined using ingestively naive snakes (Elaphe quadrivirgata) from dietarily different populations: populations from the main Japanese island, where the snakes' diet predominantly consists of sympatric frogs, and from Mikura-jima Island, where no frogs occur and the snakes thus chiefly prey on lizards. We presented chemical stimuli from six items including those from their natural and potential prey (fish, frog, lizard, mouse, water, and cologne) to newborn snakes. Significant effects of stimuli on the tongue-flick responses were detected. On the other hand, effects of population and interaction between stimuli and population were not significant, and individual comparisons revealed no significant interlocality differences in responses to either frog or lizard chemicals. Thus, our hypothesis was not supported. However, in the Mikura-jima sample, significantly fewer snakes responded to frog chemicals than in the main island sample. The significance of the inconsistency between prey recognition ability and prey availability in the Mikura-jima population are discussed. Received: October 17, 2000 / Accepted: December 14, 2000     

海南岛淡水龟类区系特点及保护优先性分析

海南岛是我国淡水龟类分布较为集中、物种丰富度高、动物区系独特的地区,已知的淡水龟有2科8属11种,占全国淡水龟种数(24种)的46％。海南岛淡水龟物种密度为3．2种／10^4km^2,均为东洋界成分,其中华南区种4种,占36．4％;华中-华南区共有的种7种,占63．6％;海南特有种2种,占岛内淡水龟种数的18．2％。海南岛淡水龟占华南地区淡水龟种数(19种)的57．9％。海南与广东、广西和香港的淡水龟类区系关系也十分密切,与它们的生物相似值分别为0．76、0．64和0．47。目前,中国75％的淡水龟类濒危,海南岛81．8％的淡水龟类濒危。分析表明,海南岛应是我国淡水龟类资源优先保育的地区。     

广东内伶仃岛的生物资源及自然保护规划

广东省内伶仃岛生物资源较为丰富,共有野生维管植物133科379属569种,其中广东新记录种10种;苔藓植物19科34属61种,广东新记录种10种,各类动物有兽类数十种,包括国家珍稀濒危保护动物猕猴（Macac mulatta)等,两栖爬行类30多种,鸟类近110处,昆虫超过447种。 此外,内伶钉岛也是一个较为封闭的生态系统,根据该岛各类生物资源和生态环境特点,宜划分为核心区,旅游－科普区和实验－缓冲区3部分,对各区的特点、性质,以及全岛的发展规划进行了初步探讨。     

农业景观中山体的植物多样性分布：地形和土地利用的综合影响

 农业景观中,山体是被广阔农田包围的生境岛屿,是生物多样性保护的重点地段。存在人类干扰时,决定山体植物多样性的主要因素不是面积、年龄和隔离程度,而是地形和土地利用。在这种情况下,从岛屿生物地理学的观点来理解生物多样性的分布规律是不合适的,因此本文采用直接对比分析方法对此进行说明。选择环渤海地区河北省遵化市（39°55′～40°22′ N, 117°34′～118°14′ E）境内的10个山体,从山顶到山底沿坡面设置样带。记录不同坡位的土地利用类型及宽度,分层调查各个土地利用类型的乔木层、灌木层和草本层物种丰     

Intertidal Communities of Severnyi Bay (Northern Sakhalin Island)

The paper describes the composition, structure and vertical distribution of intertidal communities in Severnyi Bay (the northern extremity of Sakhalin Island).