Inability to demonstrate calcite precipitation by bacterial isolates from travertine

Bacteria were isolated from 10 actively depositing travertine sites in Europe and North America. Forty‐four isolates were characterized and 33 (75%) were identified as Pseudomonas. Thirty isolates produced base on glucose‐peptone media and 32 isolates produced ammonia from amino acids. Because of the low bacterial biomass in the travertines, the formation of bases, including ammonia was not considered to be significant in carbonate precipitation. None of the bacteria was observed to precipitate calcite from supersaturated calcium carbonate solutions in vitro.     

Microbial origin of travertine fabrics—two examples from Southern Germany (Pleistocene stuttgart travertines and miocene riedöschingen Travertine)

Summary In Southern Germany, two examples of travertines of different age and depositional morphology were examined in detail. Travertines are laminated carbonate rocks formed by precipitation from mineral and/or thermal waters. They include characteristic facies types, such as bushy layers (‘shrubs’) referred to calcification of branching microbes (‘Dichothrix’-morphotype), laminar microbial mats, peloidal layers, and gas bubble layers formed within the sediment. In travertines, microbial activity is the most important factor for carbonate precipitation. Tufas differ from travertines by their abundance of molds of higher plants (leaves, reed, moss, green algae). They may be associated with travertines, but do not exhibit strict travertine facies types. Tufas are common in normal fresh water environments. Contrary to travertines and tufas, calcareous sinters usually occur in restricted areas like spring fissures, caves, or in pores, where microbial activity is not totally absent, but not of paramount importance for precipitation. Pedogenetic processes, which can alter travertine deposits, are responsible for large-scale features such as tepee-structures, and some intraclastic layers, and microscopic structures like endolithic borings andMicrocodium. Travertines may also grade into lacustrine limestones with Characeae, ostracods, and aquatic gastropods.     

Pleistocene mammals from travertine deposits of the Denizli basin (SW Turkey)

The Denizli basin, which is famous by its modern travertine accumulations such as that of Pamukkale is located at the eastern junction of Büyük Menderes and Gediz grabens in the western Anatolian extensional province. This basin contains large travertine formations, the origin and age of which are still debated. This study briefly recalls the tectonic and stratigraphic context of travertine occurrences and describes some vertebrate remains, which have recently been recorded in travertines. The material mainly consists of jaw fragments referred to Equus aff. suessenbornensis Wüst, 1901, lower teeth and antlers of Dama sp. and some lower teeth of Bos sp. The presence of E. aff. suessenbornensis, indicates a Middle Pleistocene age in agreement with thermoluminescense dating of the travertines.     

Surprisingly high orchid diversity in travertine and forest areas in the Huanglong valley, China, and implications for conservation

The presence of such a large number of terrestrial orchid species in a small area (ca. 1 km²) of the Huanglong valley in southwestern China is uncommon for this country. Studying the relationship between the distribution patterns of these orchid species and their microenvironments may help us understand this uncommon phenomenon. We established 662 1 m × 1 m plots, measured the cover of each species and found that there were 33 orchid species distributed mainly in two different habitats, i.e. travertine areas and forest. In the travertine areas, 30 orchid species were found; the six most common ones being Cypripedium bardolphianum, Cypripedium flavum, Cypripedium tibeticum, Galearis diantha, Ponerorchis chusua and Phaius delavayi. However in the forested habitat, we found 21 orchid species; the most common ones being Tipularia szechuanica and Goodyera repens. Travertine areas had a higher number of orchid species as well as higher numbers of orchid species per plot as compared to forest. Light availability seems critical to the performance and distribution of orchid species. Stream flow through the travertine area during the orchids growing season appears to be an important factor in shaping and maintaining stable microenvironments favorable to the growth and reproduction of orchids. The results presented in this study suggest that some orchid species in the travertine area might be threatened if the travertine stream flows were to change or be disrupted.     

Formation of laminate travertines at bagno vignone,Italy

Travertine at Bagno Vignoni, Tuscany, is deposited from thermal CO₂‐rich water up‐welling from an artificial pool, Bagno Grande, which contains a thick benthic mat of cyanobacteria. The travertine mound, over 40 m in height, consists of calcite feather crystals and micrite. Over much of the mound, but particularly in the lower part, the travertine is finely banded, with pale bands of feather crystals alternating with dark bands containing micrite. Deposition rate measurements showed that the bands were formed daily, with the slightly narrower and darker bands formed at night. These nocturnal bands also contained wind‐borne dust. It is postulated that the dust caused heterogeneous nucleation of micrite and reduced the development of feather crystals. The deposition rate of travertine ranged from 127 to 348 μm/day and was highest at the top of the mound. Water analysis conducted over 27 h demonstrated a pronounced diurnal variation in the dissolved carbon dioxide of Bagno Grande, consistent with the photosynthetic activity of the benthic cyanobacteria. This variation could be traced to the base of the travertine mound but was not alone responsible for the higher deposition rate during the day. Water temperature on the mound also increased during the day and would have aided CO₂ evasion. Photosynthetic activity on the mound itself appeared to have far less influence on the carbon dioxide flux than Bagno Grande. The upper mound supported unlithified mats of the cyanobacteria Lyngbya (Phormidium) laminosum and Spirulina labyrinthiformis. These mats sometimes possessed fine travertine laminae resulting from cyanobacterium phototaxis and may have been responsible for some lamination in the upper mound. The CO₂ flux measurements indicated that overall, atmospheric evasion of carbon dioxide was more significant to travertine deposition than photosynthetic activity.     

Uranium series dating in paleoanthropology

Many hominid and archaeological sites contain materials that were formed or deposited synchronously with the site and can be dated by uranium-series methods, principally ²³⁰Th/²³⁴U dating. The range of the method is approximately 350,000 years. U-series dating yields most accurate results when applied to chemically precipitated calcium carbonate, which occurs in stalagmitic layers, travertines, and lacustrine limestones. Materials such as bone and shell are less reliable. Using mass spectrometry (MS), a precision of ±1% is attainable, whereas conventional alpha counting optimally gives a precision of ±5%. Mass spectrometric dating requires smaller samples, potentially allowing determination of ante quem dates for calcite coatings on hominid fossils and associated faunal skeletons.     

Rivularia halophila sp. nov. (Nostocales,Cyanobacteria): the first species of Rivularia described with the modern polyphasic approach

ABSTRACT

Natural populations of a Rivularia-like cyanobacterium were collected from the carbonate deposits of the temporarily flooded littoral zone of a hypersaline, high elevation lake, The Laguna Negra, Andes, Argentina. Subsequently, the cyanobacterial strain PUNA-NP3, named after its origin (Puna Volcanic Plateau) was isolated from these Rivularia-like rounded, pillow-like, black microbial mats. None of the previously described species of the genus Rivularia occupy inland, hypersaline aquatic environments. After morphological examination of this strain, we found clear morphological autapomorphies, such as mucilaginous pads at the bases of the young trichomes, wide trichomes and filaments, and uniquely branched trichomes. Furthermore, based on results from 16S rRNA phylogeny and analysis of the 16S-23S ITS region, PUNA-NP3 was found to be an independent lineage of the evolutionary tree. Based on the combination of ecological, morphological and molecular evidence, we name strain PUNA-NP3 Rivularia halophila sp. nov. a new species under requirements of the International Code of Nomenclature for Algae, Fungi and Plants.     

The Early Holocene treeline in the southern French Alps: new evidence from travertine formations

Aims The present paper concerns the analysis of macro‐remains (plant imprints) from high altitude travertine deposits dating back to the early Holocene (9800 BP ). Our results allow us to discuss treeline location and ecology, and to supplement previous data based on pollen from natural sediments and charcoal from natural soil. Location The travertine under study is located in the Queyras massif, in the southern French Alps, along the Italian border. The site is situated on a south‐facing slope. Methods The travertine deposit has been dated by ²³⁰Th/²³⁴U. Taxonomic identification of plant imprints was achieved by comparison of the morphology of fossil specimens with extant material. Results Imprints of Pinus uncinata (cones and needles), broad‐leaved trees (Betula cf. pubescens, Populus tremula and Salix spp.), and unidentified trunks have been found. The plant assemblage records the existence at a high altitude (2200 m) of shade‐intolerant vegetation at around 9800 BP. Our data indicate that the treeline limit was at least 100 m higher than previously thought. The morphological features of the travertine, the plant assemblage and trunk diameters indicate that during the travertinization process, vegetation around the site was probably dense with tall upright trees. Main conclusions Our data show that Pinus uncinata and broad‐leaved trees developed at 2200 m, while regional pollen analyses locate the treeline at lower altitudes. Different research methods appear to provide different results. Around 9800 BP tree regeneration and growth were made possible up to at least 2200 m a.s.l., probably as a result of warmer and wetter summers. Warmer conditions are inferred from the predicted increase in incoming solar radiation based on calculated orbital variations, and wetter conditions are inferred from the build‐up of the travertine.     

Études stratigraphique,sédimentologique et paléomagnétique des travertins de Kocabaş, Bassin de Denizli,Anatolie, Turquie,contenant des restes fossiles quaternaires

Stratigraphic, sedimentological and paleomagnetic studies were conducted on the travertine from Denizli Basin, near Kocabas village, in the Denizli region in Turkey, following the paleontological discovery in 2002. The stratigraphic and sedimentological studies show at least two main cycles of mass travertine, separated by a fluvial deposit and overlain by a fluvio-lacustrine deposit. These travertines must have formed in environments with strong hydrodynamics (streams or waterfalls) and are preferentially located at breaks of slopes. The paleomagnetic study shows that all the quarry travertine presents reverse magnetic polarity. On the other hand, the detrital fluvio-lacustrine deposit above the travertine presents normal geomagnetic polarity, except at the top, where it is reversed. Given the presence of an archaic Homo erectus skull and Villafranchian paleontological remains in the upper travertine unit, the whole travertine dates from the upper Matuyama, and is more recent than the Olduvai event (1.78 Ma). The normal polarity recorded in the upper fluvio-lacustrine deposit could correspond to the Cobb Mountain excursion, dated to 1.22 Ma.     

Effect of tomato genotypes with varying levels of susceptibility to Tetranychus evansi on performance and predation capacity of Phytoseiulus longipes

Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) is an invasive tomato pest in several African, American, Asian and European countries, with potential to reduce yield by up to 90%. Populations of the predaceous phytoseiid mite Phytoseiulus longipes Evans (Acari: Phytoseiidae) has been reported to have high potential for controlling T. evansi. However, tomato genotypes can potentially affect the performance of T. evansi and the predation ability of P. longipes. We evaluated the performance and predation capacity of P. longipes feeding on T. evansi nymphs on the two cultivated genotypes widely grown in Western Africa and a breeding genotype. The two commercial evaluated genotypes were Tounvi (susceptible, with few trichomes), TLCV15 (susceptible, with many trichomes), and the breeding genotype was SPJ-05–2018 (partially resistant with many glandular trichomes) selected from interspecific crossing TLCV15 and PI 13447 (highly resistant wild tomato genotype). We hypothesized that the susceptible genotype (with fewer trichomes) would be more favorable for P. longipes when compared to the susceptible or partially resistant genotypes (with a higher numbers of non-glandular or glandular trichomes). Intrinsic rate of increase (r) and predation potential (ω) of P. longipes were significantly reduced on SPJ-05–2018, possibly due to a negative effect of its glandular trichomes. Although the intrinsic rate of increase was higher on both susceptible genotypes (TLCV15 and Tounvi), predation potential was higher on TLCV15. Our results refuted the hypothesis that T. evansi-susceptible genotype with fewer trichomes would be more favorable to P. longipes.

     

Antagonism between herbivore‐induced plant volatiles and trichomes affects tritrophic interactions

We used tomato genotypes deficient in the jasmonic acid (JA) pathway to study the interaction between the production of herbivore‐induced plant volatiles (HIPVs) that serve as information cues for herbivores as well as natural enemies of herbivores, and the production of foliar trichomes as defence barriers. We found that jasmonic acid‐insensitive1 (jai1) mutant plants with both reduced HIPVs and trichome production received higher oviposition of adult leafminers, which were more likely to be parasitized by the leafminer parasitoids than JA biosynthesis spr2 mutant plants deficient in HIPVs but not trichomes. We also showed that the preference and acceptance of leafminers and parasitoids to trichome‐removed plants from either spr2 or wild‐type (WT) genotypes over trichome‐intact genotypes can be ascribed to the reduced trichomes on treated plants, but not to altered direct and indirect defence traits such as JA, proteinase inhibitor (PI)‐II and HIPVs levels. Although the HIPVs of WT plants were more attractive to adult insects, the insects preferred trichome‐free jai1 plants for oviposition and also had greater reproductive success on these plants. Our results provide strong evidence that antagonism between HIPV emission and trichome production affects tritrophic interactions. The interactions among defence traits are discussed.     

Effects of foliar apple trichomes on Galendromus occidentalis (Nesbitt) (Acari: Phytoseiidae): preferences,fecundity and prey consumption

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Role of leaf glandular trichomes of melon plants in deterrence of Aphis gossypii Glover

External characteristics of the leaf epidermis and their effects on behaviour of Aphis gossypii Glover were evaluated in two Cucumis melo L. genotypes, ‘Bola de Oro’ (aphid susceptible) and TGR‐1551 (aphid resistant) in order to explore their role in the early rejection of TGR‐1551 by this aphid. No differential effects of epicuticular waxes on aphid behaviour were observed. The type, distribution and number of trichomes on melon leaves were also studied. Pubescence in melon, measured as the number of non‐glandular trichomes per cm², was not sufficient to prevent aphid settling. However, there was a high density of type I glandular trichomes on leaves of the aphid‐resistant genotype. According to microscopic observations and stain testing, these trichomes store and secrete phenols and flavonoids. Free‐choice tests were conducted to determine the effect of these glandular trichomes on A. gossypii preference, revealing that aphids reject leaf disks of TGR‐1551 from the onset of the experiment. Additional experiments after removal of leaf type I glandular trichome exudates showed that A. gossypii preferred washed TGR‐1551 leaf disks over unwashed disks, while this effect was not observed in experiments using washed and unwashed ‘Bola de Oro’ leaf disks. These results suggest that a high density of glandular trichomes and chemicals secreted by them deter A. gossypii and disturb aphid settling on TGR‐1551.     

Human Vagus Nerve Branching in the Cervical Region

BackgroundVagus nerve stimulation is increasingly applied to treat epilepsy, psychiatric conditions and potentially chronic heart failure. After implanting vagus nerve electrodes to the cervical vagus nerve, side effects such as voice alterations and dyspnea or missing therapeutic effects are observed at different frequencies. Cervical vagus nerve branching might partly be responsible for these effects. However, vagus nerve branching has not yet been described in the context of vagus nerve stimulation.ResultsCervical vagus nerve branching was observed in 29% of all cases (26% unilaterally, 3% bilaterally) and proven histologically in all cases. Right-sided branching (22%) was more common than left-sided branching (12%) and occurred on the level of the fourth and fifth vertebra on the left and on the level of the second to fifth vertebra on the right side. Vagus nerves without branching were significantly larger than vagus nerves with branches, concerning their diameters (4.79 mm vs. 3.78 mm) and cross-sections (7.24 mm² vs. 5.28 mm²).DiscussionCervical vagus nerve branching is considerably more frequent than described previously. The side-dependent differences of vagus nerve branching may be linked to the asymmetric effects of the vagus nerve. Cervical vagus nerve branching should be taken into account when identifying main trunk of the vagus nerve for implanting electrodes to minimize potential side effects or lacking therapeutic benefits of vagus nerve stimulation.     

Micro‐morphological characteristics of seed and ovary trichomes of Iranian Glaucium Mill. species (Papaveraceae) and their taxonomic importance

Seeds and trichomes of 15 taxa of the genus Glaucium distributed in Iran were examined by light microscopy (LM) and scanning electron microscopy (SEM). The seeds are slightly shiny to rather shiny, however, strongly shiny seeds were also observed in some species (G. corniculatum and G. grandiflorum). The basic shape of the seeds is semicircular to reniform, but reniform and elongated reniform seeds were found in G. oxylobum and G. elegans, respectively. The sculpturing of the testa surface are verrucate–rugulate (most frequent type), verrucate–granulate, verrucate–perforate, verrucate–lineolate, rugulate–granulate, rugulate and ocellate. Elongated polygonal epidermal cells dominate in most taxa investigated, but there are polygonal and irregular polygonal cells in a few taxa. The investigated species have two types of trichomes on the ovary: tuberculate and non‐tuberculate. The non‐tuberculate trichomes are of two subtypes: pilose and squamiform. Based on the number of cells, the squamiform trichomes were further divided into two groups (uniseriate and multiseriate) differing in shape, size and cellular structure. The results show that the micro‐morphological characteristics of seed and ovary trichomes provide useful and significant information for separation of species and taxa within species and a diagnostic key to the taxa is provided.     

Solitary terminal cells of Aphanizomenon gracile (Cyanobacteria,Nostocales) can divide and renew trichomes

An attempt was made to find evidence that morphologically distinct terminal cells of filamentous cyanobacterium Aphanizomenon gracile strain CCALA 8 are capable of dividing and forming trichomes. Based on our current knowledge, the division of morphologically diversified terminal cells is possible in nostocalean cyanobacteria. However, this process has been observed only in a few species. Terminal cells of A. gracile differ morphologically from other vegetative cells of a trichome, as they are not hyaline and can sometimes be found as solitary cells in cultures. Hence, it was reasonable for us to suspect that these cells are capable of dividing and forming trichomes. We observed terminal cells under a light and transmission electron microscope. Microscopic observations revealed that the septum formed in both solitary terminal cells and in terminal cells attached to trichomes. Our study is the first to demonstrate division and renewal of trichomes in terminal cells of A. gracile. Previously, such mode of reproduction was described only for another nostocalean cyanobacterium Raphidiopsis mediterranea. Moreover, our findings further emphasize the variability among members that belong to the genus Aphanizomenon , in which a type species (A. flos‐aquae) has hyaline cells incapable of dividing and renewing trichomes, while A. gracile can additionally propagate by solitary terminal cells division. This additional feature distinguishing A. gracile from typical species of Aphanizomenon, such as A. flos‐aquae, might be valuable for resolving taxonomic position of the species considering ambiguous genetic relationship between A. gracile and A. flos‐aquae.     

Zinc hyperaccumulation and cellular distribution in Arabidopsis halleri

Although Arabidopsis halleri ( = Cardaminopsis halleri) is known as a Zn hyperaccumulator, there have been no detailed studies on Zn accumulation, tolerance and cellular distribution in this species. In a hydroponic experiment, A. halleri grew healthily with Zn concentrations varying from 1 to 1000 μ M , without showing phytotoxicity or reduction in root or shoot dry weights. The concentration of Zn in the shoots increased from 300 μ g g ^{? 1} dry weight in the 1 μ M Zn treatment to 32 000 μ g g ^{? 1} in the 1000 μ M Zn treatment. Approximately 60% of the total Zn in the shoots were water‐soluble, and there was no evidence of Zn and P co‐precipitation. Both citric and malic acid concentrations in the shoots were not significantly affected by the Zn treatments, whereas in the roots there was a positive response in both organic acids to increasing Zn in solution. Cellular distribution of Zn, Ca and K in frozen hydrated leaf tissues was examined using energy‐dispersive X‐ray microanalysis. Zinc was sequestered in the base of trichomes, whereas the middle and upper parts of trichomes were highly enriched with Ca. Mesophyll cells appeared to have more Zn than the epidermis, probably because the latter were very small in size. Similarities and differences between A. halleri and the other well‐known Zn hyperaccumulator, Thlaspi caerulescens, are discussed.     

Regional‐scale dominance of non‐framework building corals on Caribbean reefs affects carbonate production and future reef growth

Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non‐framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO₃ m^?2 yr^?1. However, non‐framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non‐framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean‐wide dominance of non‐framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non‐framework building coral species will further reduce carbonate production rates below ‘predecline’ levels, resulting in shifts towards negative carbonate budget states and reducing reef growth potential.     

Contexte géographique et géologique du site de Kocabaş, Bassin de Denizli,Anatolie, Turquie

The site of Kocaba? is located in the Denizli Basin, in western Anatolia, 400 km southwest of Ankara, 360 km south of Istanbul, 200 km east-southeast of Izmir and 150 km northwest of Antalya. The Denizli Basin depression, at the junction of the Buyuk Menderes and Gediz grabens, which began to form at the beginning of the Miocene, was filled in around the edges, along fault lines, by significant travertine formations, some of which are still active today. The age of the Kocaba? travertines, which yielded the Kocaba? Homo erectus skullcap, was evaluated by thermoluminescence at 828,000 years, by electron spin resonance (ESR) at 1,110,000 years and by the ²⁶Al/¹⁰Be cosmogenic nuclide method to more than 1.22 Ma and less than 1.5 Ma, a date which has been confirmed by magnetostratigraphy and biochronology.     

Commercial Yellow Sticky Strips more attractive than yellow boards to western cherry fruit fly (Dipt., Tephritidae)

Bright yellow sticky rectangles made of paper boards were previously identified as the most effective traps for capturing western cherry fruit fly, Rhagoletis indifferens Curran (Dipt., Tephritidae). However, no data on the effectiveness of commercial sticky yellow plastic traps against R. indifferens have been reported. In tests conducted in sweet cherry trees [Prunus avium (L.) L.] in Washington state (USA) using ammonium carbonate as the chemical lure, commercial plastic ‘Yellow Sticky Strips’ made of translucent high‐impact polystyrene captured ~two or three times more flies than commercial sticky yellow‐folded Pherocon^® AM and Alpha Scents boards. Yellow Sticky Strips also minimized captures of non‐target flies and bees per surface area compared with Pherocon^®AM and/or Alpha Scents boards. Trap size and adhesive type were not factors for greater catches of R. indifferens. However, more flies were caught on the shade‐facing side of Yellow Sticky Strips, which was brightly illuminated, than on the shade‐facing side of boards, which was darker, suggesting differential light passage was a factor. The Yellow Sticky Strips could be very useful for monitoring R. indifferens in detection programmes and based on the results of this study can replace yellow boards. They are also useful because they are relatively unattractive to non‐target insects.