Taphonomy and taxonomy of a vertebrate microsite in the mid-Cretaceous (Albian–Cenomanian) Blackleaf Formation,southwest Montana

The vertebrate fauna of the Cretaceous Blackleaf Formation of southwest Montana remains largely undocumented. A microsite (BL1) discovered in the Flood Member in the Lima Peaks area, Montana, consists of a green siltstone and yields taxa previously unreported from the formation, including several dinosaurs: a hypsilophodont, dromaeosaurid, tyrannosauroid, hadrosaurid and an ankylosaurian. Non-dinosaurian taxa include goniopholidid and Bernissartia crocodilians; Glyptops, cf. chelydrid and other turtles and at least two neopterygiian fish. This diversity corresponds well with the fluvial–deltaic–estuarine environment interpreted for the uppermost unit of the Flood Member. Taphonomic data and sedimentologic relationships suggest that this assemblage represents a floodplain depression accumulation. Comparisons with contemporaneous faunas from around the Western Interior of the USA suggest a remarkably consistent faunal makeup, at least at the family level, existed across western North America in the mid-Cretaceous.     

MODERN LAND MOLLUSCA FROM MAIDEN CASTLE, DORSET, AND THEIR RELEVANCE TO THE INTERPRETATION OF SUBFOSSIL ARCHAEOLOGICAL ASSEMBLAGES

To aid in the interpretation of molluscan assemblages from archaeologicalsites, modern land mollusc faunas were analysed from 43 turfsamples on a transect of the ramparts of Maiden Castle, Dorset,in chalk grassland. Distinct faunas in terms of species composition,molluscan abundance and species diversity as defined by theShannon and Brillouin indices were present. They were relatedto habitat factors, especially lime, structural diversity andwarmth. The results allow the identification of different grasslandtypes and show that distinct assemblages can occur in closeproximity, delineated by sharp boundaries. However, interpretationof subfossil assemblages from archaeological contexts is bestmade in terms of general relations of relevance between assemblagesand environment because matching by species composition betweenmodern faunas and subfossil assemblages is generally impossible. (Received 17 November 1993; accepted 1 February 1994)     

Index,Vol. 34, 1999

To investigate whether similar physiognomic areas support similar faunas, the richness, similarity, and community structure of the ant fauna attracted to baits in an area of the Brazilian Cerrado sensu stricto at the core of the domain and in two Cerrado 'islands' (one of sensu stricto and another of 'cerradão') were compared. In each locality, four collecting events were performed (two during the day and two at night) capturing ants attracted to 400 sardine baits (200 in soil, 200 in vegetation). Ants of six subfamilies, 33 genera, and 121 species were identified visiting baits in the three areas (180 species estimated). The most speciose genera were Camponotus (27 species), Pheidole (13), Solenopsis (11), and Crematogaster (8). The similarity values between pair sites can be considered medium in relation to other studies. The highest value was recorded for the core area and the 'island' of Cerrado sensu stricto (Morisita-Horn = 0.57). The two Cerrado 'islands' were found to be 0.44 similar and the core area and the 'cerradão' 0.41 similar. The ordination analysis (non-metric multidimensional scaling) revealed discontinuities in species distributions between areas of Cerrado sensu stricto and 'cerradão,' and distinctive ant faunas relative to the temporal (nocturnal and diurnal) and foraging niches (ground and vegetation). The ant fauna at ground level in the 'cerradão' and Cerrado sensu stricto showed the greatest dissimilarity. The data suggest that areas of Cerrado are characterized by relatively high local ant fauna richness, and that community structure is influenced by the distance between sites and the diversity of vegetation.     

Quantitative studies of modern wet-ground molluscan faunas from Bossington, Hampshire

There have been few quantitative studies of modern Mollusca in Britain, especially from wet-ground areas. This is particularly true of the English chalklands, which is surprising given the focus of sub-fossil molluscan research in that area. Those studies that are available highlight the difficulty of separating molluscan faunas from structurally complex habitats such as fen and carr. Quantitative molluscan data from a variety of wet-ground habitats situated within the chalklands of southern England were analysed using an indirect ordination technique, Principal Components Analysis. This demonstrated that the separation of faunas from structurally complex wet-ground habitats is possible. The numerical separation does not rely on indicator species, but is a function of variation of the predominant species. It is suggested that further studies of this type might aid the interpretation of sub-fossil Mollusca from wet-ground contexts.     

Airborne Laser Scanning as a Tool for Lowland Floodplain Vegetation Monitoring

Monitoring of three-dimensional floodplain vegetation structure is essential for ecological studies, as well as for hydrodynamic modelling of rivers. Height and density of submerged vegetation and density of emergent vegetation are the key characteristics from which roughness parameters in hydraulic models are derived. Airborne laser scanning is a technique with broad applications in vegetation structure mapping, which therefore may be a promising tool in monitoring floodplain vegetation for river management applications. This paper first provides an introduction to the laser scanning technique, and reviews previous studies on the extraction of vegetation height and density of forests, low vegetation and meadows or unvegetated areas. Reliable predictions using laser scan data have been reported for forest height (R²=0.64–0.98), parameters related to forest density, such as stem number, stem diameter, biomass, timber volume or basal area (R²=0.42–0.93), and herbaceous vegetation height (summer condition; R²=0.75–0.89). No empirical relations have been reported on density of herbaceous vegetation. Laser data of meadows and unvegetated areas show too much noise to predict vegetation structure correctly. In a case study for the lower Rhine river, the potential of laser scan mapping of vegetation structure was further explored for winter conditions. Three laser-derived metrics that are often reported in the literature have been applied to characterize local vertical distributions of laser reflections. The laser data clearly show the large structural differences both between and within vegetation units that currently are the basis of floodplain vegetation and roughness mapping. The results indicate that airborne laser scanning is a promising technique for extraction of 3D-structure of floodplain vegetation in winter, except for meadows and unvegetated areas.     

Vegetation and stream pattern as indicators of water movement on the Magela floodplain,Northern Territory

Magela Creek is a hydrologically complex waterway which drains Australia's two largest uranium deposits, carries a pastoral and tourist industry and has been proposed for inclusion in a national park. In this study, the vegetation and stream patterns of the floodplain are described and are used as indicators of surface water movement through the system. The Magela floodplain was found to be a freshwater lagoon, enclosed at its outlet by, the floodplain of the East Alligator River; the vegetation types are direct indicators of water depth within the lagoon. The capacity of the lagoon is approximately 60 × 10⁶ m³, the average daily input during the wet season is approximately 3% of the lagoon volume and during the dry season the lagoon dries out to approximately 5 × 10⁶ m³ of perennial swamp. The lagoon is maintained by the East Alligator River and so its hydrology must not be studied in isolation but in relation to the larger system to which it belongs.     

New national and regional bryophyte records, 10

Abstract

The discovery of Paludella squarrosa (Hedw.) Brid., new to Ireland, is reported. This Boreo-arctic Montane species has a relic distribution in western and central Europe and was formerly more widespread. The reasons for its decline and its documented extinction from Britain and the Netherlands in recent times are discussed. The vegetation and ecology of the Irish locality are described. The associated species include Leiocolea rutheana, another Boreal relic species and a second record for Ireland.     

Vegetation dynamics related to sediment accumulation in Kushiro Mire, northeastern Japan

We investigated the relationship between vegetation changes and site condition in Kushiro Mire, northeastern Japan, where massive depositions of sediment from the watershed have been observed over the last several decades. These changes also included the changing area of floodplain forest. To determine the factors that induced the changing floodplain forest area and the effect of sediment accumulation on floodplain vegetation, we examined site conditions where vegetation had recently changed. We classified the pattern of vegetation change as new forest (formerly meadow), new meadow (formerly forest), stable forest (forest since 1967), and stable meadow (meadow since 1967) with the help of aerial photographs taken in 1967, 1977, and 2000. The survey results showed that the quadrats were divided into six vegetation types based on current vegetation composition. All new forests comprised alder (Alnus japonica) and were divided into two vegetation types. New meadows were also considered alder forest based on remnants of former forest and divided into two vegetation types. The site condition showed better correspondence to the pattern of vegetation change than the current vegetation composition, though it had a significant relationship with the latter. In new forests, high water table and a relatively high content of clay and silt characterized the site condition, whereas in new meadows, low water table and high sand content were the site characteristics. We discuss these site characteristics in the context of alder’s adaptability to site. It is suggested that coarse sediment probably along with intense flooding and fine sediment coupled with high water table contributed to the disappearance and establishment of alder forests, respectively.     

The fauna of free-living gamasid mites (Parasitiformes,Mesostigmata) in the northern Taiga: an analysis of the zonal specificity

According to the data of four-year sampling, the territory of the Pinega Reserve (Arkhangelsk Province) is populated by more than 117 gamasid mite species belonging to 18 families. A relative richness of this fauna is obviously associated with intensive karst processes. A number of species (arctic, Siberian, mountainous) is limited to karst localities characterized by low soil temperature and a short vegetation period. When comparing the local Mesostigmata faunas from different regions, it was suggested that only species lists of unspecialized free-leaving forms should be used. Changes in the species richness of separate families and their fraction in the total suborder diversity along the latitudinal gradient from dry steppes to polar deserts are individual, reflecting different ecological potencies. The zone of deciduous forests is characterized by the richest fauna of Mesostigmata as a whole and of the majority of its families. The northern boundaries for the distribution of separate families are outlined. The number of free-leaving species in the families Ascidae, Phytoseiidae, and Zerconidae varies most smoothly along the latitudinal gradient. Even in polar deserts, Ascidae and Phytoseiidae are represented by more than a single species. It is in the taiga that the family Ascidae becomes the most diverse among Mesostigmata. In the tundra zone, this tendency is more pronounced, and in polar deserts this family constitutes 70–83% of species in local faunas, represented mainly by the genus Arctoseius.     

Do feral buffalo (Bubalus bubalis) explain the increase of woody cover in savannas of Kakadu National Park,Australia?

Aim To study changes in woody vegetation in both floodplains and eucalypt savanna over a 40‐year period using multi‐temporal spatial analysis of variation in density of a large introduced herbivore, the Asian water buffalo (Bubalus bubalis). Feral buffalo built up to high densities in the study area until c. 1985, after which a control programme almost eliminated the animals. From 1990, low densities of managed buffalo were maintained inside an enclosure. We compared trends in woody vegetation when buffalo were high‐density feral, low‐density managed or absent. Location The study area was located in and around a 116‐km² buffalo enclosure inside Kakadu National Park, in monsoonal northern Australia. Methods We analysed sequences of digitized and geo‐rectified aerial photographs, acquired in 1964, 1975, 1984, 1991 and 2004, to chart changes in woody cover on the floodplain and in the savanna. On the floodplain we assessed whether trees were present at these times at 14,568 points, and buffalo density was estimated from the density of animal tracks. In the savanna we estimated woody cover at pre‐selected sites. Generalized linear modelling was used to analyse changes in woody vegetation, using elevation and presence of woody vegetation in neighbouring points on the floodplain, and buffalo regime and initial woody cover in the savanna. Results Changes in animal track density reflected park‐wide historical estimates of buffalo numbers. Tree cover increased in both floodplain and savanna, but this was only weakly related to buffalo density. The best predictor of whether a floodplain cell converted from treeless to woody, or the converse, was the woodiness of neighbouring vegetation. There was slightly less thickening with high buffalo densities. In savanna, low densities of managed buffalo were weakly associated with increases in tree cover relative to either high densities of feral buffalo or no buffalo. Main conclusions Our study indicates that buffalo are not a major driver of floodplain and eucalypt savanna dynamics. Rather, the observed increase in woody cover in both savanna and flood plains concords with regional trends and may be related to increased atmospheric CO₂, increasing rainfall and changing fire regimes during the study period.     

Fish–macrophyte relationship in the Anavilhanas Archipelago, a black water system in the Central Amazon

The characin fish fauna associated with floating meadows on the floodplain of the Rio Negro was studied at the beginning of the rising water period. Two microhabitats were identified in the meadows ( Paspalum plus Oryza vegetation and pure Oryza vegetation) and their influence on characin abundance tested. No significant difference in characin numbers was found between microhabitats. Three species accounted for 82% of characins captured: Hemigrammus levis, Metynnis cf. hypsauchen and Moenkhausia lepidura. Metynnis cf. hypsauchen was more abundant in Paspalum plus Oryza vegetation than in the other microhabitat. A similar difference was not found for H. levis and M. lepidura . The diets of the three species were similar in the smaller size classes, consisting primarily of Cladocera. However, the diets differed in the larger size classes with M. cf. hypsauchen foraging mainly on filamentous algae, M. lepidura on wild rice and H. levis on Cladocera. The diet shift is apparently an optimal foraging strategy, while the differences in microdistribution appear to be related to predation risk.     

贵州剑河寒武系苗岭统凯里组太阳女神螺类几何形态学研究*

太阳女神螺类(helcionellids)是寒武纪常见的一类软体动物,广布全球,多见于碳酸盐岩沉积地层中,而布尔吉斯页岩型生物群中却少有报道。贵州剑河凯里生物群是典型的特异埋藏化石库,产有700余件太阳女神螺类标本,这在世界各地同时期的布尔吉斯页岩型生物群中是很少见的。本文对贵州剑河八郎寒武系凯里组太阳女神螺类化石标本进行了系统研究,采用几何形态测量学的典型变量分析进行量化分析。几何形态测量学(Geometric morphometrics)是用界标点或轮廓线等来描绘生物的形态或者标记特征部位及器官,将生物形态特征归纳为数据变化的定量学方法,其中的典型变量分析(Canonical Variate Analysis)是多变量分析中进行判别分析的一个重要方法,可以用于多组数据之间的判别。CVA判别结果显示:利用壳体侧视轮廓线判别Dorispira属中三个种的正确率为92%,验证了Dorispira accordinonata、D.taijiangensis和D.cf.pearylandica化石种分类合理性。本文研究表明即使壳体形态较为相似的类群,也可以较为准确地使用CVA量化其中的差别,...     

History, genetic differentiation and conservation strategies for disjunct populations of Sibiraea species from Southeastern Europe and Asia

The genetic structure of Croatian Sibirea (Sibiraea croatica), a rare and endemic tertiary relic of Croatian and Herzegovinian flora, and its relationship with sibirea from Southern Russia and Southern Siberia (Sibiraea altaiensis) was studied using amplification, restriction and sequencing of the ITS region in genomic DNA and cpDNA and their comparisons with sequences of the Rosaceae species obtained from GenBank. The restriction analysis and separation in agarose gel showed no differences in length of the digested cpDNA between or within populations. Sequencing showed only minor variability between populations. Only a minor difference of 6 bp duplication in DNA amplified with ccmp 10-R and trnM primer pair was noticed in two geographically distinct populations. No differences in the restriction pattern for the ITS region in genomic rDNA indicates that all samples of sibirea belong to the same species since the ITS region was proven to be conserved within one taxonomic species. The minor differences that were␣obtained support the hypothesis that sibirea is an old tertiary relic that shows a minor variability, confirming previous preliminary results from comparisons of the Croatian and Altaic sibireas at the morphological level. Our data suggests that Croatian sibirea from the Balkan is a disjunct population identical to the Altaic species. Due to its disjunct occurrence in Southeastern Europe, the endemic status in the Dinarics, a relic that survived the glaciations, it deserves active conservation approaches through support of traditional use of high-mountain pastures for reducing natural reforestation of sibirea ancient sites.     

Plant Species with Potential as Food,Nesting Material,or Tools at a Chimpanzee Refuge Site in Caddo Parish,Louisiana

Surplus chimpanzees live in research laboratories where they will likely remain for the rest of their lives. An alternative to laboratory housing is an outdoor enclosure in a warm climate. Before construction, researchers should conduct a vegetation survey because chimpanzees use vegetation daily. Chimp Haven, Inc. is developing a chimpanzee sanctuary in Caddo Parish, Louisiana, and we conducted a vegetation survey at the site to 1) characterize the abundance and structure of vegetation; 2) identify plants with utility as food, nesting material, or tools; 3) determine the abundance and distribution of useful vegetation; and 4) identify any possibly hazardous vegetation. We established 48 plots, quantified the woody vegetation, and identified potentially useful and hazardous plant species from the published literature. Vegetation at the site was secondary growth from logging of loblolly pine (Pinus taeda), the most abundant tree. Other abundant trees included oak (Quercus spp.), elm (Ulmus spp.), sweetgum (Liquidambar styraciflua), and maple (Acer spp.). Small plants (1–9.9 m tall) constituted 95% of all vegetation. Forty-one of 64 plant species have edible vegetative parts, while 35 species have edible reproductive parts. We identified 55 potential nesting trees by size (dbh ≥ 25 cm) and 4 species used as tools by captive great apes. Useful vegetation was concentrated in areas with topographic relief or in a floodplain, while flat areas with fields had less. We recommend that the floodplain be cropped for fruit and browse and enclosures encompass areas with relief and fields, creating a diverse habitat.     

Contribution to the knowledge on relic Stipa spp.-dominated ultramafic grasslands of the Central Balkans

The heterogeneity of the ultramafic vegetation of the Central Balkans is rather great. Although this vegetation has been continuously investigated, some gaps are still to be filled. For example, the lack of available data on ultramafic vegetation of the Republic of Macedonia is evident. In that light, we have investigated different relic Stipa species-dominated dry grasslands over ultramafic bedrock. Twenty relevés were made and compared to the similar vegetation types (i.e. Potentilla visianii, Centaureo kosaninii-Bromion fibrosi, “Thymion jankae”, Saturejo-Thymion and Alyssion heldreichii) by means of numerical analyses. We distinguished one new association and one informal community, providing them with diagnosis and lists of diagnostic, constant and dominant species. We also determined their syntaxonomic positions and relations to ultramafic syntaxa from the neighboring countries.     

Foraminiferida from Neogene sediments,Vestfold Hills,Antarctica

Sediment samples from several locations in the southern part of the Vestfold Hills have been examined for their foraminiferid content. Those from Early Pliocene sediments of Marine Plain immediately east of Burton Lake contain little foraminiferid evidence of marine deposition. Those from mid-late Holocene sections in and near the lakes contain good open marine faunas of species now known to be living on the continental shelf west of Cape Darnley.Foraminiferid faunas characterized by calcareous forms are most common, the most prevalent dominated by Globocassidulina crassa.The faunas examined contrast markedly with those in the present Prydz Bay which is characterized by agglutinated forms.The results, in relation to planktonic faunas, conflict with an earlier record of a diverse fauna.     

Vegetation analysis of the Mediterranean region of Nile Delta

Thirty-four vegetation clusters identified in the present study, after the application of TWINSPAN and DCA multivariate techniques, were assigned into 8 vegetation types, each of definite vegetation and habitat characters. The suggested vegetation types are well segregated along the DCA axis one which reflects soil moisture, salinity (as indicated by EC values), fertility (as indicated by the organic matter and nitrogen contents) and species diversity gradients. In general, soil moisture and soil fertility increase and species diversity decreases with the following sequence of vegetation types:Echinops spinosissimus-Ononis serrata on inland sand dunes,Pancratium maritimum on coastal sand dunes,Halocnemum strobilaceum-Salsola kali in saline sand deposits,Atriplex halimus-Chenopodium murale along the terraces and slopes of drains,Arthrocnemum glaucum-Tamarix nilotica in salt marshes,Chenopodium murale along the slopes of drains,Phragmites australis along the littoral zones of drains, andLemna gibba-Potamogeton crispus in the water zone. This sequence reflects also a gradient of human interference, starting with the vegetation of the less disturbed habitats (sand dunes and saline sand deposits) and ending with the fully man-made habitats (drain zones).     

The floodplain grasslands of the Middle Lena-river II. Classification

The grassland vegetation of the Middle Lena valley is described. The syntaxonomy of floodplain grassland vegetation includes 19 associations of five classes (Cleistogenetea squarrosae, Hordeetea brevisubulati Calamagrostietea langsdorffü, Phragmiti-Magnocaricetea, Thero-Salicornietea). An example of a typical Lena-river floodplain ridge-hollow vegetation complex is shown. Most of the syntaxa reflect the peculiarity of the East-Siberian vegetation and are absent from Europe. The geographical distribution of these syntaxa is described. The relation of the vegetation of different parts of the floodplain to the vegetation of the alases of Central Yakutia is discussed.     

Understory vegetation as an indicator for floodplain forest restoration in the Mississippi River Alluvial Valley,U.S.A.

In the Mississippi River Alluvial Valley (MAV), complete alteration of river‐floodplain hydrology allowed for widespread conversion of forested bottomlands to intensive agriculture, resulting in nearly 80% forest loss. Governmental programs have attempted to restore forest habitat and functions within this altered landscape by the methods of tree planting (afforestation) and local hydrologic enhancement on reclaimed croplands. Early assessments identified factors that influenced whether planting plus tree colonization could establish an overstory community similar to natural bottomland forests. The extent to which afforested sites develop typical understory vegetation has not been evaluated, yet understory composition may be indicative of restored site conditions. As part of a broad study quantifying the ecosystem services gained from restoration efforts, understory vegetation was compared between 37 afforested sites and 26 mature forest sites. Differences in vegetation attributes for species growth forms, wetland indicator classes, and native status were tested with univariate analyses; floristic composition data were analyzed by multivariate techniques. Understory vegetation of restoration sites was generally hydrophytic, but species composition differed from that of mature bottomland forest because of young successional age and differing responses of plant growth forms. Attribute and floristic variation among restoration sites was related to variation in canopy development and local wetness conditions, which in turn reflected both intrinsic site features and outcomes of restoration practices. Thus, understory vegetation is a useful indicator of functional progress in floodplain forest restoration.     

Distribution of the stands with Urtica dioica L. along the Lužnice River floodplain on the border between Austria and Czechoslovakia and land management

The effects of different management practices (mainly mowing, grazing, nutrient enrichment) on floodplain vegetation were compared between the Austrian and Czech part of the Lunice River floodplain using nitrophilous vegetation with Urtica dioica. The vegetation samples situated on crosswise transects (40 in total) were used for the analysis of vegetation. Correlations between the floodplain width on these transects and the proportions (expressed as percentage of the total floodplain width) of selected characteristics (Urtica dioica and Phalaris arundinacea stands and managed areas) were not statistically significant. Differences in the proportions of selected characteristics between the two parts of the floodplain were not significant either, except differences in the proportion of managed areas and species richness (higher species richness and proportion of managed areas are in the Austrian part of the floodplain). The different environmental variables were used in ordinations (DCA and CCA) of vegetation samples. In the DCA, four groups of samples were interpreted. In the CCA changes the moisture gradient was the most important one. The transect distance (from the first transect in Austria) and the soil moisture had the closest relationship to the species data.