贵州洞穴淡水、陆生贝类区系及新种记述

首次报道了贵州省安龙县、贵阳市、独山县、荔波县、安顺市、开阳县、息烽县、盘县、兴义市、大方县、普定县等39个洞穴内不同生境的淡水、陆生贝类,经鉴定得淡水、陆生螺类共计71种,分隶于15科,36属,其中淡水螺类3科4属5种;陆生螺类66种,12科32属;1新种,即荔波双边凹螺Chamalycaeus libonensis sp.nov.附有种类名录,栖息环境及地理分布,并对洞穴中的淡水、陆生贝类区系组成进行了讨论,对新种进行了详细的描述,与近似种进行了比较。     

盘县大洞古人类遗址的地层和古气候研究

贵州盘县大洞的堆积物,自上而下可以分为3层。大洞主体堆积物为角砾堆积,来源于洞顶灰岩的崩塌,另外有人类遗物以及洞外片流作用带入的泥砂。人类化石、旧石器和哺乳动物化石主要分布在第2层角砾堆积中。堆积物在洞厅各部位均有相应分布,属同一沉积序列。已知的早期人类活动时间大约从260ka．B．P．开始,到142ka．B．P．前后结束,对应于深海氧同位素的第6、7阶段。角砾层下段,发育一套遭强烈溶蚀和风化的堆积物,地球化学分析结果显示其湿热的沉积环境,时间大约在260—180ka B．P．期间,对应于深海氧同位素第7阶段;大洞堆积物在气候变化周期上与黄土、青藏高原冰期序列可以对比。     

Hunting,disturbance and roost persistence of bats in caves at Ankarana,northern Madagascar

Surveys and monitoring of 37 caves in and around the Ankarana Special Reserve, northern Madagascar, yielded evidence of hunting of bats and potential disturbance of bats by miners and tourists, and colony counts for several bat species of potential conservation concern. Colony size decreased by 95% and 14% for a colony of Hipposideros commersoni and a colony of Eidolon dupreanum, respectively, when recent evidence of hunting occurred at those colonies and those declines are probably attributable to hunting. Evidence of hunting occurred commonly at the roosts of those species and most commonly at the roosts of Rousettus madagascariensis. Hunting of pteropodids was associated with high vulnerability of roosts to hunters, little forest buffer between the cave and open savannah and the absence of tombs in the cave. Roost sites of the hunted species persisted for at least several years and this regularity may facilitate hunting. This work supports the ranking of E. dupreanum, R. madagascariensis and H. commersoni as species of conservation concern. Managers should consider the impact of tourist visits on bats and of increasing access to caves for tourism. Conservation efforts for the hunted species should also seek to protect vulnerable and unprotected cave roosts.     

The diet of Myotragus balearicus Bate 1909 (Artiodactyla: Caprinae), an extinct bovid from the Balearic Islands: evidence from coprolites

Myotragus balearicus Bate 1909 is an artiodactyl Caprinae endemic to the Balearic Islands which became extinct more than 4000 years ago. Coprolites produced by this species have been collected from the excavation of Holocene cave sediments in Cova Estreta (Serra de Tramuntana, Mallorca). The pollen content of several samples of coprolites has been studied in order to determine the diet of Myotragus. Myotragus balearicus from Cova Estreta was a browser, and consumed huge amounts of box, Buxus balearica , a plant known for its high content of steroidal alkaloids. The coprolites are very fine textured, probably due to the result of a very efficient digestive process.     

三只羊岩溶峰丛洼地果-药复合栽培模式研究

岩溶峰丛洼地的耕地可分为3种类型：洼底平地、带状阶梯地和高坡石穴地。传统的玉米＋黄豆种植模式在三种类型耕地上的产值均很低,需要调整品种结构,改革种植模式。该文报道了基于三种耕地特点的四种果一药复合种植试验,即沙田柚＋绞股蓝、大果枇杷＋射干＋扶芳藤、无核黄皮＋射干＋扶芳藤、四月桃＋金银花。初步结果显示,四种模式均可大幅度提高耕地的产值,可作为岩溶峰丛洼地地区生态农业可持续发展的重要模式。     

Aggregated spatial distributions of species in a subtropical karst forest,southwestern China

Aims Spatial distribution patterns of species reflect not only the ecological processes but also the habitat features that are related to species distribution. In karst topography, species distribution patterns provide more specific information about their environments. The objectives of this study are as follows: (i) to analyse and explain the spatial distribution patterns of conspecific trees in an old-growth subtropical karst forest; (ii) to investigate pattern changes at different spatial scales; (iii) to test the spatial pattern similarity (or dissimilarity) between trees at different abundances, diameter at breast height classes, canopy layers and different functional groups (shade tolerance and seed dispersal mode); (iv) to examine whether habitat heterogeneity has an important effect on the species spatial distribution.Methods The spatial distributions of woody species with ≥20 individuals in a 1-ha subtropical karst forest plot at Maolan in southwestern China were quantified using the relative neighbourhood density Ω based on the average density of conspecific species in a circular neighbourhood around each species.Important findings Aggregated distribution is the dominant pattern in the karst forest, but the ratio of aggregated species in total species number decreases with an increase in spatial scale. Less abundant species are more aggregated than most abundant species. Aggregation is weaker in larger diameter classes, which is consistent with the prediction of self-thinning. Seed dispersal mode influences spatial patterns, with species dispersed by animals being less aggregated than those dispersed by wind and gravity. Other species functional traits (e.g. shade tolerance) also influence the species spatial distributions. Moreover, differences among species habitat associations, e.g. with rocky outcrops, play a significant role in species spatial distributions. These results indicate that habitat heterogeneity, seed dispersal limitation and self-thinning primarily contribute to the species spatial distributions in this subtropical karst forest.     

Effects of monsoon on distribution patterns of tropical plants in Asia

Comparing with other regions, Asia is mostly dominated by the monsoon climate and tropical plants can be found at the furthest places away from the equator. Understanding the role of monsoon in the dispersal and evolution of tropical plants is helpful for exploring the distribution patterns of vegetation and mechanisms underlying the origin and maintenance of biodiversity in Asia. In summer, there are three types of monsoon in Asia, i.e. East Asia Monsoon, South Asia Monsoon, North-west Pacific Ocean Monsoon. The summer monsoon climate in Asia originated at about 40 Ma, when the early angiosperm evolved and started its diversification in Southeast Asia and South China. It suggested that the monsoon may facilitate the quick speciation and spread of early angiosperm. Monsoon climate facilitates the northward spread of Asia’s tropical plants and some tropical plants can be found even at Yarlung Zangbo River and the boundaries of Guizhou-Guangxi-Yunnan. Such effetcs largely change distribution patterns of zonal vegetation and even causes local vegetation types in some places with unusual topography such as tropical seasonal rainforests, monsoon rainforests, savanna and grassland along dry-hot valley in Southwest China, coastal savanna in West Hainan Island. The three summer monsoons interact at Southwest China and Indo-China Peninsula and these regions are dominated by limestone landscapes and high mountains with big rivers. Some Asia-endemic tropical taxa even formed a diversification and endemism center at this region, which may be a reason for the formation and maintenance of Indo-Burma biodiversity hotspots with global warming, the monsoon may further promote the northward spread of tropical plants and may have fundamental effects on biodiversity and flora evolution in South China.     

不同喀斯特小生境中土壤丛枝菌根真菌的遗传多样性

为探明西南喀斯特地区小生境土壤中丛枝菌根真菌(AMF)的遗传多样性特征, 利用巢式PCR和变性梯度凝胶电泳相结合的分子生物学方法, 对茂兰3种植被类型下的小生境(石缝、石沟、土面) AMF遗传多样性进行了研究。结果发现: 各类小生境都含有丰富的AMF遗传多样性, 灌木林土面的多样性指数和物种丰富度最高, 为4.06和68; 次生林石缝的最低, 为3.16和29, 所研究的9个小生境多样性指数和物种丰富度的平均值分别高达3.67和48, 高于同类研究在其他地区的结果, 这可能主要与喀斯特生态系统复杂的结构和较高的植物多样性有关; 聚类分析显示各类小生境间的AMF群落结构差异显著, 相似性指数最高仅为0.45, 说明小生境所带来的空间异质性对AMF的遗传多样性产生了显著影响; 基因测序显示球囊霉属(Glomus)极有可能是喀斯特地区AMF的优势菌属, 在以后筛选喀斯特地区的高效生态恢复菌种时可重点考虑球囊霉属的一些菌种。     

贵州省普定县不同植被演替阶段的物种组成与群落结构特征

通过对贵州省普定县喀斯特地区不同植被演替阶段群落的调查, 研究了植被演替过程中群落物种组成和群落结构的变化。结果表明, 该地区的植被主要处于5个演替阶段, 即次生乔木林、乔灌过渡林、藤刺灌丛、稀灌草丛以及火烧干扰后的蕨类植物群落。本次调查共记录到植物365种, 隶属89科218属。其中, 蕨类植物31种, 隶属14科23属; 种子植物334种, 隶属75科195属。物种分布较多的科主要有蔷薇科、菊科、禾本科、百合科、忍冬科、唇形科、莎草科、樟科、葡萄科和水龙骨科。随着正向演替的推进, 物种丰富度增加, 群落结构趋于复杂化。藤刺灌丛与乔灌过渡林群落层次不明显, 次生乔木林分层明显。从藤刺灌丛向次生乔木林演替的过程中, 小径级个体所占比例明显降低, 高于1.3 m植物的总密度、乔木密度和藤本密度都先升高后降低, 而灌木密度呈逐渐降低的趋势。对喀斯特地区植被的恢复提出了参考措施。     

滇石林喀斯特植物群落不同演替阶段的溶痕生境中木本植物的更新特征

喀斯特生境与生物多样性的关系及其对人为干扰的响应是喀斯特地区生态恢复的重要内容。该文以云南石林为例对此进行研究。根据喀斯特溶痕与土壤、植物生长发育关系把石林的溶痕生境划分为溶蚀廊道、溶槽、裂隙溶沟、溶坑和溶蚀石堆等5种。依据石林的现有植被与演替特征, 选择了原生林、次生林、灌丛、灌草丛和石漠化草丛5种群落进行调查。在每一个样地中设置10个10 m × 10 m的样方, 采用记名计数样方法分片调查溶痕生境中的木本植物, 并区分更新层的萌生苗与实生苗; 采用Shannon-Wiener指数、Pielou指数、Simpson指数、Margalef指数进行生物多样性计算。调查结果显示: (1)溶痕生境的长度、宽度变化较大。溶痕生境结构比例随群落演替而变化, 其原因可能在于所处演替阶段和干扰程度的差异; (2) 在各种溶痕生境中, 随着群落的退化, 实生更新物种数与实生株数大致表现为递减, 在严重退化阶段部分溶痕生境中没有实生苗的分布, 而萌生更新的物种数则以灌丛为峰值向两极减少, 个体数变化较大。计算结果显示: 在各类溶痕生境(溶蚀石堆除外)中, 实生苗的多样性、丰富度、均匀度大致呈现随群落的退化而降低, 优势度增加; 萌生苗多样性、均匀度、丰富度除溶蚀廊道递减的趋势明显外, 其他类型变化较大。不同演替阶段植物更新策略不同。在喀斯特森林生态系统中, 随着群落的退化, 植物更新逐步趋向于营养繁殖, 其部分原因在于特殊的溶痕生境(除溶蚀廊道)能保存一些植物残体, 而这些残体在反复的干扰下不断萌出茎干(采用营养繁殖)以实现物种的持续生态位, 萌生茎干的成熟为生物多样性维持与生态恢复提供繁殖体来源。