Climate driven changes in the submerged macrophyte and phytoplankton community in a hard water lake

We studied the changes in the submerged aquatic vegetation (SAV) and phytoplankton community in a hard water lake during different meteorological conditions. We hypothesized that variations in climatic conditions (precipitation and temperature) can influence the physicochemical parameters of water and, in turn, affect SAV and phytoplankton development. The investigations were performed in Lake Rogóźno (the West Polesie region, Eastern Poland) over 10 years from 2003 to 2013. The physicochemical parameters, the structure of macrophytes and the phytoplankton community in the dry (2003–2006, DP) and wet periods (2007–2013, WP) were analyzed. Between the dry and wet periods, the water color and the concentration of dissolved organic carbon (DOC) increased considerably, whereas water conductivity decreased. Other parameters (concentration of nutrients, water reaction and transparency) were comparable during both periods. When the precipitation and water level were low (DP), charophytes dominated the SAV and cyanobacteria dominated the phytoplankton community. After the precipitation and water level increased (WP), the charophyte population declined and the vascular plants and bryophytes dominated. Furthermore, flagellated algae belonging to the dinophytes and cryptophytes were the most numerous in the phytoplankton community. These changes in the SAV and phytoplankton were linked with the variations of physicochemical parameters determined by the total precipitation and mean air temperature in March.     

英国钙华苔藓植物区系特征及其主要钙华沉积类型

根据1998— 2000年作者采自英国39个钙华沉积区1245份的野外苔藓植物标本研究, 英国钙华苔藓植物区系具有下列特征:(1)区系种类由19科34属50种(含变种亚种)组成, 其中含英国钙华苔藓新记录26种;(2)区系生活型含高丛集型(10 %)、矮丛集型(32%)、交织型(44 %)、扇型(2 %)和平埔型(12 %)5 种类型;(3)区系地理成分含北温带分布(46 %)、温带欧洲分布(6 %)、欧洲-非洲分布(2 %)、欧洲-北美分布(10 %)、旧世界温带分布(4%)和世界广泛分布(34%)等6种成。根据钙华生长的环境特征, 英国苔藓植物钙华可划分为泉华、瀑华、溪流钙华和洞穴弱光带钙华4 种基本类型及12 种小类型。      

贵州豹子洞石灰岩与红土型金矿藓类植物比较研究

红土型金矿是岩溶地区新发现的一类金矿类型,其特点是石灰岩基岩与金矿红土混生。为了探索岩溶地区苔藓植物特征, 2004年8月我们对贵州安龙县豹子洞石灰岩和红土型金矿苔藓植物进行了比较研究。野外在红土型金矿区和石灰岩各设5个采样点, 共观察和采集了105份苔藓标本。对苔藓植物的区系组成、地理成分、结构及物种多样性进行统计分析,结果表明: 该地区两种基质上共有40种,隶属9科25属,未发现苔类和角苔类。其中,石灰岩上有7科、11属、12种藓类植物; 红土型金矿上有6科、18属、28种藓类植物。豹子洞石灰岩与红土型金矿区藓类植物其种相似性系数为0. 05。Sha nno n-Wiene r 指数和种间相遇机率指数较低, Simpso n 指数则较高,表明苔藓植物分布受基质影响明显。      

Bioindication of Gold by Aquatic Bryophytes

As arsenopyrite is frequently present in auriferous deposits, concentrations of gold were measured in aquatic bryophytes collected from streams in zones of arsenic mineralization in the Polish and Czech Sudety Mountains. Data were compared with analyses of aquatic bryophytes from streams in non As mineralization areas with only background concentrations of Au. The highest contents of Au in bryophytes surpass the background concentration of this element in plants and are found in areas characterized by the presence of arsenopyrites.     

法国阿尔卑斯山(Mt.Alps,France) 溪流型喀斯特瀑布水生苔藓植物群落生态研究

对法国阿尔卑斯山(M t. Alps, France) 6个溪流型喀斯特瀑布水生苔藓植物群落进行了研究。报道典型瀑布水生苔藓群落14个,苔藓植物种类由11科16属20种(含变种亚种) 组成; 生殖系统由雌雄异株( Dio ecious, 95% )和雌雄同株异苞( Auto ecious, 5% )两种类型构成,无性繁殖是繁殖的主要方式; 区系地理成分含北温带分布( 60% ) 、欧洲- 北美分布( 10% )、旧世界温带分布( 5% )和世界广泛分布( 25% ) 等4种成分; 生活型含高丛集型( 20% )、矮丛集型( 10% )、交织型( 60% )和平铺型( 10% ) 4种类型。根据喀斯特沉积环境特征, 划分瀑布水生苔藓群落为峡谷瀑布苔藓群落、温泉瀑布苔藓群落、瀑布水帘洞苔藓群落、悬崖瀑布苔藓群落和悬崖季节性瀑布苔藓群落等5种生态类型。法国阿尔卑斯山溪流型瀑布生物喀斯特沉积物具有分布广泛,但沉积规模较小的特点。      

Frullania pinnata spec. nov. (Frullaniaceae,Porellales), a new leafy liverwort in mid-Cretaceous Burmese amber from Myanmar

An inclusion in Cretaceous amber from Myanmar is described as a new fossil species in the extant liverwort genus Frullania. The name Frullania pinnata is proposed for the taxon that is characterized by entire underleaves paired with a conspicuous pinnate branching pattern, two distinctive and stable morphological features. Entire underleaves are known in several extant Frullania species but had not previously been documented in Frullania in amber. The combination of morphological characters in this new fossil species is unknown in any crown group lineage of Frullania, and may very well represent a stem lineage element of the genus. This discovery is important because it expands our understanding of the diversity of Frullaniaceae in the Burmese amber forest as well as important ramifications for the phylogenetic reconstruction of extant Frullania lineages.     

马头山自然保护区苔藓植物区系研究

通过对马头山自然保护区1180余号标本的鉴定，现已知该地区共有苔藓植物69科，149属，265种及1亚种，1变种。其中，Leucodon temperatus Akiyama为中国大陆分布新记录，大萼苔（Cephalozia ambigua)，钩叶粗蔓藓（Meteoriopsis ancistrodes),Isocladiella surcularis(Dix.)Tan,Trichosteleum stigmosum,Mitt.为华东新记录，水生湿柳藓（Hygroamblystgium fluviatile)，梨蒴珠藓（Bartramia pomiformis)拟兜叶藓（Horikawaea dubia)，柔叶毛柄藓（Calyptrochaeta japonica)，角状刺枝藓（Wijkia hornschuchii)等14种为江西新记录。本文全面分析了马头山苔藓植物区系成分，将其划分为12种类型，其中以东亚成分为主，热带，亚热带成分次之，温带成分居第三位，分别为39．36％，30．92％，26．51％，东亚成分中的中国－日本成分77种，占30．92％。东亚特有属，刺疣藓属（Trichosteleum)，水生湿柳藓等属种分布特点的讨论，以及和邻近地区比较，反映马头山苔藓植物区系与国内其它苔藓分布区之间的联系，具有较明显的过渡性质，成为我国苔藓植物区系中典型的亚热带类型。     

Landform and Vegetation Change in the Greaves Creek Basin: An asymmetric hanging valley in the Blue Mountains,New South Wales

Greaves Creek has cut a hanging valley through the entire Triassic sandstone sequence near Blackheath in the western Blue Mountains, New South Wales. Downstream of Beauchamp Falls, it cuts into Permian strata in the Grose Gorge. The hanging valley has a valley-in-valley structure. The narrow inner valley is bounded by high cliffs and its floor is cut by a deep narrow slot canyon where stream incision has occurred without valley widening. The course of the creek is related to joint directions. Intense jointing, minor faulting and sapping influence the stability of cliffs but up to 30m of incision has occurred without valley widening in the slot canyon. Topographic asymmetry expressed as unequal slopes of the valley sides is related to differential insolation, erosion, vegetation cover, bioturbation and fire intensity. In the western Blue Mountains and elsewhere in the Sydney Basin asymmetric slopes occur in many other valley-ridge systems, particularly those whose long axes are oriented between about east-west and north-east-south-west. Vegetation structure and floristics within Greaves Creek valley are related to physiography of the valley and to aspect through their effects on fire, moisture availability, light availability, soil depth and temperature.