Permian gastropods from the Kulogory Formation of the northern Moscow Syneclise

Permian gastropods from the Kulogory Formation (Sakmarian) were studied based on the author’s material and the collection of Yakowlew (Central Research Geological Prospecting Museum (TsNIGR Museum), St. Petersburg). Lectotypes for Arribazona tschernyschewi (Yakowlew, 1899) and Microdoma kulogorae (Yakowlew, 1899) were designated. Six species are described; four of them are new and two are assigned to the new genera (Biarmeaspira verideclinata gen. et sp. nov., Globodoma yakowlewi gen. et sp. nov., Glabrocingulum (Glabrocingulum) stankovskyi sp. nov., and Euconospira? pinegensis sp. nov.). The high degree of polymorphism in the dominant species of uniform assemblages is probably the result of their development in “undersaturated” paleocommunities of closed lagoons with gradually increasing concentration of sulfate ions.     

Paleobiological implications of shell repair in recent marine gastropods from the northern Gulf of California

Shell repair frequencies in eleven species of Recent gastropods from the northern Gulf of California vary with habitat, shell morphology and intensity of durophagous predation. Squat shells with large apertures tend to have high repair frequencies (0.25–0.50). Shell thickness at the aperture and shell size are not correlated with frequency of repair. Significant intraspecific variation in repair frequency exists between habitats. Samples from rocky habitats have statistically higher repair frequencies than samples of the same species from sandy habitats. However, habitat‐related variation between species is not apparent.

Trends in co‐evolution of gastropods and their durophagous predators are based on the indirect evidence of shell repair frequencies through time. Variation in repair frequency due to environmental and morphological factors may obscure predator‐related temporal trends in repair frequency.     

An assessment of vegetation and environmental controls in the 1970s of the Mesopotamian wetlands of southern Iraq

A vast ecosystem of wetlands and lakes once covered the Mesopotamian Plain of southern Iraq. Widespread drainage in the 1990s nearly obliterated both components of the landscape. This paper reports the results of a study undertaken in 1972–1975 on the vegetation of the wetlands prior to drainage and provides a unique baseline for gauging future restoration of the wetland ecosystems in Mesopotamia. Five representative study sites were used to assess the flora, three of which were wetlands. A total of 371 plant species were recorded in the five sites, of which approximately 40% represent obligate or facultative wetland species. The wetland vegetation was classified into five major physiognomic forms (submerged, floating, herbaceous tall emergent, herbaceous low emergent and woody low emergent), which was further subdivided into 24 fresh and halophytic communities. Water levels greatly fluctuated across the different types of wetlands, and mean surface water depth ranged from below to greater than 2 m above the sediment surface, reflecting permanently, seasonally or intermittently wet habitats. Aboveground biomass was also highly variable among the communities. The Phragmites australis community, which was the most extensive community type, had the greatest biomass with an average value of approximately 5,000 g m⁻² in summer. Distribution and community composition were largely controlled by water levels and saline-freshwater gradients. Canonical correspondence analysis showed that salinity and water depth were the most important factors to explain species distribution. Environmental variables related to soil salinity separated halophytic species in woody low emergent and herbaceous low emergent forms (Tamarix galica, Cressa cretica, Alhagi mannifera, Aeluropus lagopoides, Juncus rigida, and Suaeda vermiculata) from other species. Their habitats were also the driest, and soil organic matter content was lower than those of other species. Habitats with deepest water were dominated by submerged aquatic and floating leaved species such as Nymphoides peltata, Ceratophyllum demersum, and Najas armata. Such diverse environmental conditions in the Mesopotamian wetland would be greatly affected by evapotranspiration, river water inputs from north, ground water inputs, local soil conditions, and a tide or seiche-controlled northward transgression of water from the Gulf. These environmental conditions should be considered in restoration plans if plant communities existed in the mid-1970s are to be part of the desired restoration goals. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

伊拉克两河流域中、下游盐渍土种植水稻的生态环境分析

伊拉克两河流域平原地势平坦,气候属亚热带大陆性干旱—半荒漠气候,土壤以盐渍化粉砂性粘质土壤为主。平原中部主要为氯化物—硫酸盐盐土;平原下部以氯化物盐土居多数,而且镁盐往往超过钙盐,地下水中镁离子更可达钙离子的5—10倍。水稻生育期中田间保持水层,对凋节生态环境起到良好作用。生长前期因供氧需要,需短期落干,但需注意返盐程度以免危害秧苗。因此调节水、气矛盾,并以水调温和控盐,是水稻能否顺利生长的关键。平原上自4月份开始,各月绝对最高温度都可达40℃或以上,按有些学者的说法,水稻开花时如温度超过42℃则花粉便在7分钟内死亡,但伊拉克的水稻仍能正常生长。因通过水面蒸发、稻株蒸腾以及灌溉水的调温,使稻田小气候远较旱田为缓和。当地干湿球温差常常达到20℃左右,稻株则可比稻田气温低5℃左右,后者又比附近沙漠低4—5℃。灌溉水调节稻田温度的作用,在高温季节最显著,7一8月下午1时湿土温度低于1米气温5℃以上,灌溉水又低于湿土5℃以上,加以稻田区空气相对湿度比附近沙漠区高30%,所以对改善水稻扬花的生态环境很有好处。种稻期间土壤盐分随排灌措施而波动,多次灌溉后盐分大致达到平衡,在0.15—0.30%之间。一般落干3天,可解决水、气矛盾并控制返盐。盐分对水稻的危害,早稻发芽扎根时,0—5厘米土层含盐量(以Cl-为主)在0.2一0.3%以下,5—20厘米在0.3—0.4%以下,不至造成伤害。至三叶期,0—20厘米土层含盐量在0.5%以下便不致有显著危害。高坵的盐斑往往造成死苗,而排水良好的洼坵其洗盐效果反而较好。种稻过程中土壤pH值的变化不大。     

Ammonia-oxidizing beta-proteobacteria from the oxygen minimum zone off northern Chile

The composition of ammonia-oxidizing bacteria from the beta-Proteobacteria subclass (betaAOB) was studied in the surface and upper-oxycline oxic waters (2- to 50-m depth, approximately 200 to 44 microM O(2)) and within the oxygen minimum zone (OMZ) suboxic waters (50- to 400-m depth, < or =10 microM O(2)) of the eastern South Pacific off northern Chile. This study was carried out through cloning and sequencing of genes coding for 16S rRNA and the ammonia monooxygenase enzyme active subunit (amoA). Sequences affiliated with Nitrosospira-like cluster 1 dominated the 16S rRNA gene clone libraries constructed from both oxic and suboxic waters. Cluster 1 consists exclusively of yet-uncultivated betaAOB from marine environments. However, a single clone, out of 224 obtained from the OMZ, was found to belong to Nitrosospira lineage cluster 0. To our knowledge, cluster 0 sequences have been derived from betaAOB isolated only from sand, soil, and freshwater environments. Sequences in clone libraries of the amoA gene from the surface and upper oxycline could be grouped in a marine subcluster, also containing no cultured representatives. In contrast, all 74 amoA sequences originating from the OMZ were either closely affiliated with cultured Nitrosospira spp. from clusters 0 and 2 or with other yet-uncultured betaAOB from soil and an aerated-anoxic Orbal process waste treatment plant. Our results reveal the presence of Nitrosospira-like betaAOB in both oxic and suboxic waters associated with the OMZ but with a clear community shift at the functional level (amoA) along the strong oxygen gradient.     

Rissooidean freshwater gastropods from the Vanuatu archipelago

During expeditions to Santo and the Torres islands belonging to the Vanuatu archipelago in 2006 and 2007, ten new species of tateid gastropods confined to springs, the upper most, slowly flowing regions of streams or the groundwater had been discovered. These species were now described based on shell morphology and anatomy. In accordance with geography, these characters placed the species from Vanuatu between those from New Caledonia and Fiji, suggesting a stepping stone-like dispersal across the Pacific with an origin in New Zealand and the far end on the Austral islands. We also assessed the threat status of the new species according to the IUCN Red List criteria and concluded that they should be amended by explicit incorporation of the scale of potential human impact or stochastic natural events relative to the size of the habitat of organisms.     

Climate change and the northern Russian treeline zone

The Russian treeline is a dynamic ecotone typified by steep gradients in summer temperature and regionally variable gradients in albedo and heat flux. The location of the treeline is largely controlled by summer temperatures and growing season length. Temperatures have responded strongly to twentieth-century global warming and will display a magnified response to future warming. Dendroecological studies indicate enhanced conifer recruitment during the twentieth century. However, conifers have not yet recolonized many areas where trees were present during the Medieval Warm period (ca AD 800-1,300) or the Holocene Thermal Maximum (HTM; ca 10,000-3,000 years ago). Reconstruction of tree distributions during the HTM suggests that the future position of the treeline due to global warming may approximate its former Holocene maximum position. An increased dominance of evergreen tree species in the northern Siberian forests may be an important difference between past and future conditions. Based on the slow rates of treeline expansion observed during the twentieth century, the presence of steep climatic gradients associated with the current Arctic coastline and the prevalence of organic soils, it is possible that rates of treeline expansion will be regionally variable and transient forest communities with species abundances different from today's may develop.     

中国热带生物地理北界的建议

以前多个关于中国热带北界的建议由于依据的指标和学科不同,存在很大的差异。我们基于202个中国地理区的植物区系和气象资料,对中国种子植物属的地理成分分布格局及其与气候、经纬度分布的关系进行研究,同时依据覆盖中国北纬30°以南地区的135个地方植物区系资料,对种子植物属的地理成分分布格局进行了研究。结果显示,在中国植物区系中,依据种子植物区系科和属的地理成分(即分布区类型),发现热带分布属中80%以上的区域基本上在中国南部和东南部北纬22°30'以南。在这条界线以南地区,位于基带(低海拔或水平地带性区域)的原始植被为热带森林(热带雨林、季雨林),并且具有在中国分布的典型热带植物科,但在中国西南部,热带森林沿云南西部可达到北纬24°30',在西藏南部的深切河谷可达到北纬29°。这条界线与中国的热带雨林、季雨林区划的北界相符合,亦与植物区系分区上的泛北极植物区系与古热带植物区系的地理分界线相吻合。结合中国植被和植物区系区划,我们建议将北纬22°30'作为中国南部和东南部的生物地理热带北界。这条热带北界比气候上的热带北界(21°30'N,年积温8000℃以上)更北,这暗示中国热带地区在历史上可能曾达到更北的范围,支持在古生态学研究上提出的全新世中期中国东部地区热带和亚热带常绿阔叶林曾北移的结论。     

Plagiorchis muris infection in Apodemus agrarius from northern Gyeonggi-do (Province) near the demilitarized zone

The small intestines of 6 species of rodents and 1 species of insectivore were examined seasonally for Plagiorchis muris infection in 3 different localities in northern Gyeonggi-do (Province), near the demilitarized zone (DMZ). A total of 1,496 animals, including 1,366 Apodemus agrarius, 54 Crocidura lasiura (insectivore), 32 Mus musculus, 28 Micronytus fortis, 9 Eothenomys regulus, 6 Micronys minutus, and 3 Cricetulus triton, were live-trapped at Yeoncheon-gun (n = 351), Paju-shi (804) and Pocheon-gun (343) at 3-mo intervals from December 2004 to September 2005. A total of 1,647 P. muris were collected from 72 (5.3%) A. agrarius. The infection rate was the highest in Pocheon-gun (8.2%), followed by Yeoncheon-gun (5.0%) and Paju-shi (4.2%). A higher infection rate was observed in A. agrarius captured during September (19.4%) than those captured during December (3.0%), June (2.6%), or April (0%). However, the worm burden was the highest in June (av. 32.1/animal), followed by September (24.7), December (4.0), and April (0). None of the other animal species were found infected with P. muris. The results reveal that A. agrarius is a natural definitive host for P. muris, and infection rates and worm burdens vary seasonally and geographically.     

Some Late Triassic gastropods from the Nayband formation in Central Iran

Summary Six gastropod species from the Late Triassic Nayband Formation are reported. The following taxa are introduced as new:Trochonodus iranicus n. gen., n. sp. andCryptaulax convexa n. sp. The following species are transferred toTrochonodus n. gen.:Riselloidea aliabadensis Nützel and Senowbari-Daryan 1999 (type species ofTrochonodus),Riselloidea biarmata (Münster),Riselloidea bitorquata (Hébert and Eudes-Deslongchamps),Scalaria limatula Ammon, andAmberleya trimonilis (Orbigny). The holotype ofChulitnacula jenningsi (Douglas) is newly illustrated and described. According to the current state of knowledge, the gastropod faunas of the Nayband Formation near Esfahan and near Tabas differ considerably from each other. They share onlyAnulifera binodosa. TheAnulifera species-cluster has representatives in the Norian/Rhaetian from the North Alps, Iran, Burma, and South China. Contribution to the Triassic Paleontology of Iran No. 10. For No. 9 see previous text in this volume.     

The shelled gastropods of the Solitary Islands Marine Park,northern New South Wales,Australia

ABSTRACT

Away from the major population centres, the biodiversity of Australia's shallow coastal marine waters is poorly known. The Tweed-Moreton Bioregion, covering northern New South Wales and south-east Queensland, is both a focus of marine conservation (with three marine parks), and research efforts to predict the effects of climate change through species range extensions and shifts in community composition. Here we provide the first comprehensive list of shallow-water (<30?m) shelled, gastropod macro-molluscs (>5?mm) from the Solitary Islands Marine Park, compiled from a range of sources, including field collections over a 30-year period to 2017. The Cypraeidae (50 spp.), Muricidae (47 spp.) and Conidae (32 spp.) were the most speciose families, accounting for 26% of the total inventory of 500 species from 77 families. A total of 143 species are recorded at their southern limit of distribution on Australia's east coast, most being rare, tropically affiliated taxa found at offshore island sites that receive more frequent contact with the southward-flowing East Australian Current. The inventory confirms the high biodiversity of the Solitary Islands region and the importance of ongoing conservation management.     

Lower Cretaceous gastropods from the Qayen area,Eastern Iran

Four gastropod genera are newly recorded from Lower Cretaceous deposits of the Qayen area, Eastern Iran. Based on the paleoecological interpretation of the faunal assemblage and especially on the newly identified gastropods, a shallow temperate marine environment is suggested for the fossil-bearing carbonate rocks. The gastropod assemblage shows a typically Tethyan composition comparable to those already reported from the Caucasus and Eastern Europe.     

Composition of the folded chromosome from Anabaena variabilis

A "heavy" nucleoid (folded chromosome) from A. variabilis has been isolated in preparative amounts. The composition of the folded chromosome and that of a more simple DNA--protein complex isolated from the "heavy" nucleoid of A. variabilis by chromatography on a column with methylated albumin (MAK) were studied. It was shown that the "heavy" nucleoids contain total cell DNA in a complex with the definite membrane fragment, which can be discovered by a large number of membrane proteins, phospholipids, lipopolysaccharides and amino sugars. After MAK chromatography the DNA--protein complex also contains total cellular DNA, a negligible amount of membrane polypeptides and noticeable amounts of phospholipids and lipopolysaccharides.     

Light thresholds derived from seagrass loss in the coastal zone of the northern Great Barrier Reef,Australia

There is a world-wide trend for deteriorating water quality and light levels in the coastal zone, and this has been linked to declines in seagrass abundance. Localized management of seagrass meadow health requires that water quality guidelines for meeting seagrass growth requirements are available. Tropical seagrass meadows are diverse and can be highly dynamic and we have used this dynamism to identify light thresholds in multi-specific meadows dominated by Halodule uninervis in the northern Great Barrier Reef, Australia. Seagrass cover was measured at ∼3 month intervals from 2008 to 2011 at three sites: Magnetic Island (MI) Dunk Island (DI) and Green Island (GI). Photosynthetically active radiation was continuously measured within the seagrass canopy, and three light metrics were derived. Complete seagrass loss occurred at MI and DI and at these sites changes in seagrass cover were correlated with the three light metrics. Mean daily irradiance (I_d) above 5 and 8.4 mol m⁻² d⁻¹ was associated with gains in seagrass at MI and DI, however a significant correlation (R = 0.649, p < 0.05) only occurred at MI. The second metric, percent of days below 3 mol m⁻² d⁻¹, correlated the most strongly (MI, R = −0.714, p < 0.01 and DI, R = −0.859, p = <0.001) with change in seagrass cover with 16–18% of days below 3 mol m⁻² d⁻¹ being associated with more than 50% seagrass loss. The third metric, the number of hours of light saturated irradiance (H_sat) was calculated using literature-derived data on saturating irradiance (E_k). H_sat correlated well (R = 0.686, p < 0.01; and DI, R = 0.704, p < 0.05) with change in seagrass abundance, and was very consistent between the two sites as 4 H_sat was associated with increases in seagrass abundance at both sites, and less than 4 H_sat with more than 50% loss. At the third site (GI), small seasonal losses of seagrass quickly recovered during the growth season and the light metrics did not correlate (p > 0.05) with change in percent cover, except for I_d which was always high, but correlated with change in seagrass cover. Although distinct light thresholds were observed, the departure from threshold values was also important. For example, light levels that are well below the thresholds resulted in more severe loss of seagrass than those just below the threshold. Environmental managers aiming to achieve optimal seagrass growth conditions can use these threshold light metrics as guidelines; however, other environmental conditions, including seasonally varying temperature and nutrient availability, will influence seagrass responses above and below these thresholds.     

Role of disturbed vegetation in mapping the boreal zone in northern Eurasia

Question: Is there a need for disturbance mapping integrated in the CircumBoreal Vegetation Mapping Program? Location: Eurasian boreal forest. Disturbance and mapping: The boreal zone is characterized by a multitude of natural and anthropogenic disturbance agents with importance over a wide range of spatial and temporal scales. Disturbance is a prime driver of succession in most of the boreal zone, producing landscape diversity characterized by a large‐scale vegetation mosaic of early to late succession states. When mapping the circumboreal vegetation, spatial extent, time involved from disturbance to recovered condition and likelihood of interacting disturbance types are crucial for how current vegetation is interpreted and subsequently included as map characteristics. In this paper we present examples from the boreal zone where natural and/or anthropogenic disturbance regimes dominate the state and distribution of vegetation, and possibilities for assessing the nature and extent of the disturbed regions using remotely sensed data. Conclusion: Disturbed vegetation occupies large areas in the boreal zone and related vegetation successions should be adequately represented when mapping the zone. In regions where the ‘potential natural vegetation’ is a hypothetical reconstruction from remnants of ‘natural’ vegetation it would be preferable to use the concept of ‘actual real vegetation’ for which remote sensing at coarse, medium and fine resolution is an efficient tool. The Land Cover Classification System (LCCS) may offer sufficient flexibility to incorporate information about the disturbance of circumboreal vegetation.     

About some aporrhaid and strombid gastropods from the Late Cretaceous

Sixteen species of the Stromboidea (Gastropoda) from the Late Cretaceous are described in this study. One species belongs to the Strombidae, the others to eight genera and subgenera of the Aporrhaidae. Eight species are new. They have been found in the Cenomanian of Kassenberg in western Germany, the Coniacian of the Mungo River in Cameroon, the Santonian of the Eastern Cape Province of South Africa, the Santonian/Campanian of the Ariyalur area in southern India, the Campanian of northern Spain, and the Maastrichtian of the Western Desert in Egypt. Two species ofDrepanocheilus from South Africa are considered stem-group representatives of the aporrhaids which inhabited the Weddellian Province in the early Tertiary. One new species of the strombid genusHippocrenes is regarded as an early species of the evolutionary lineage leading to the Seraphsidae. The new species areLatiala? ponsi, Drepanocheilus herberti, Drepanocheilus triliratus, Drepanocheilus (Tulochilus) jouberti, Graciliala quaasi, Kaunhowenia catalanica, Kaunhowenia punctata andHippocrenes kussi.     

Epidemiology of Echinococcus granulosus in Arbil province, northern Iraq, 1990-1998

During the period 1990-1998, 99 cases of human cystic hydatidosis (12.4 cases per year) were surgically treated at the two main hospitals in Arbil province, northern Iraq, and from this the human occurence for the province was estimated to be 2 per 100,000 inhabitants. In the same area, 1270 sheep, 550 goats and 320 cattle were examined at slaughter for hydatid cysts and prevalence rates were found to be 15.0%, 6.2% and 10.9%, respectively. A decreasing tendency in livestock prevalences was found towards the end of the study period. As in humans, most of the hydatid cysts in livestock were located in the liver. Fertility of sheep cysts, i.e. those containing protoscoleces, was found to be significantly higher (64%) than that of goats (35.7%) and cattle (29.8%). The percentage of fertile cysts containing viable protoscoleces varied between 63 and 82% in the livers and between 72 and 79% in the lungs of the different animal species. A total of 97 stray dogs were examined post-mortem in the years 1991, 1992 and 1998, and Echinococcus granulosus worms were found in the intestines of 48 dogs (49.5%). High worm burdens (> 1000) were observed in 37% of the dogs, medium worm burdens (200-1000) in 41%, and low worm burdens (< 200) in 22%. In 1998, the prevalence of canine echinococcosis (24.3%) was found to be significantly lower than in 1991 (70.4%) and 1992 (60.6%). The prevalence of human hydatidosis did not differ significantly over the years, but the study confirmed that hydatidosis is endemic in northern Iraq, and that housewives, labourers and farmers appear to be at the greatest risk of infection.     

Dynamics of Trade in the Ancient Mesopotamian "World System"

Maritime trade in the Arabian Gulf connected Mesopotamia with societies in the Gulf and with the Indus during the Bronze Age. This article explores the Gulf trade in light of shifting consumption patterns and of various political forces at work within and between regions, in order to define the socioeconomic place of the trade in center-periphery relations. Through time the consumption of certain commodities, notably copper and grain, became deeply embedded in the changing political economies of Mesopotamian and Gulf societies, and the trade formed a basic economic dimension of center-periphery relations in western Asia. At the same time, other forces—political, military, and cultural—configured center—periphery relations in western Asia as deeply as the economic ones, and provided the context within which the trade occurred. Using the Gulf trade as an example, the article offers a framework for considering the political and cultural, as well as economic, character of ancient center-periphery systems.