First record of the cryptic fishes Ptereleotris calliura (Gobiidae) and Liopropoma rubre (Serranidae) from the Veracruz reef system in Mexico

Based on several in situ observations, the species Ptereleotris calliura (family Gobiidae) and Liopropoma rubre (family Serranidae) are added to the taxonomic fish inventory of the Veracruz reef system, Mexico. While P. calliura was found on sandy substratum in the lagoon, L. rubre was detected on the reef slope. With their addition, the checklist of reef fishes in the Veracruz reef system is expanded to 479 species. Given these findings, we predict that additional survey efforts (beyond visual transects) will reveal more previously unrecorded species of cryptic fishes in the Veracruz reef system.

Plasticity in habitat use of two native Ponto-Caspian gobies, Proterorhinus semilunaris and Neogobius fluviatilis: implications for invasive populations

The Ponto-Caspian region is an important source area for some invasive gobiid fishes. These fishes have colonised several freshwater ecosystems in Europe, as well as in North America. As knowledge on their habitat utilisation in their native range remains limited, the seasonal habitat uses of Western tubenose goby, Proterorhinus semilunaris and monkey goby Neogobius fluviatilis were studied in four natural lakes in the Marmara Region (NW Turkey). Habitat use of both species was highly variable between the lakes and seasons, with P. semilunaris showing higher plasticity. In general, the main habitats used by P. semilunaris were shallow waters in littoral areas that had vegetation cover, whereas N. fluviatilis consistently used sandy substratum in deeper waters that lacked vegetation. These results suggested there was high plasticity in the habitat utilisation of these two gobiids, especially in P. semilunaris, which potentially facilitates their ability to establish and invade novel environments. The habitats that are especially vulnerable to P. semilunaris invasion are medium size substrates which provide individuals with sufficient interstitial space for refuge. Waters providing differing habitats, such as sandy substrata, might inhibit their colonisation, but are potentially more vulnerable to N. fluviatilis invasion.

New Insights on the Impact of Tidal Currents on a Low-gradient, Semi-enclosed, Epicontinental Basin—the Curtis Formation, East-central Utah, USA

Based on a methodic sedimentological analysis, the Late Jurassic (Oxfordian) Curtis Formation unravels the intricate facies variability which occurs in a tide-dominated, fluvially starved, low-gradient, semi-enclosed epicontinental basin. This unit crops out in east-central Utah, between the eolian deposits of the underlying Middle Jurassic (Callovian) Entrada Sandstone, from which it is separated by the J-3 unconformity, and the conformable overlying supratidal Summerville Formation of Oxfordian age. A high-resolution sedimentary analysis of the succession led to the recognition of eight facies associations (FA) with six sub-facies associations. Based on the specific three-dimensional arrangement of these eight facies associations, it is proposed to separate the Curtis Formation into three sub-units: the lower, middle and upper Curtis. The J-3 unconformity defines the base of the lower Curtis, which consists of upper shoreface to beach deposits (FA 2), mud-domi­nated (FA 3a) and sand-dominated heterolithic subtidal flat (FA 3b), sand-rich sub- to supratidal flat (FA 4a) and correlative tidal channel infill (FA 4c). It is capped by the middle Curtis, which coincides with the sub- to intertidal channel-dune-flat complex of FA 5, and its lower boundary corresponds to a transgressive surface of regional extent, identified as the Major Transgressive Surface (MTS). This surface suggests a potential correlation between the middle and the upper Curtis and the neighboring Todilto Member of the Wanakah Forma­tion or Todilto Formation. The upper Curtis consists of the heterolithic upper sub- to intertidal flat (FA 6) and coastal dry eolian dunes belonging to the Moab Member of the Curtis Formation (FA 7), and it conformably overlies the middle Curtis. The spatial distribution of these sub-units supports the distinction of three different sectors across the study area: sector 1 in the north, sector 2 in the south-southwest, and sector 3 in the east. In sector 1, the Curtis Formation is represented by its three sub-units, whereas sector 2 is dominated by the middle and upper Curtis, and sector 3 encompasses the extent of the Moab Member of the Curtis Formation. This study also highlights the composite nature of the J-3 unconformity, which was impacted by various processes occurring before the Curtis Formation was deposited, as well as during the development of the lower and middle Curtis. Local collapse features within the lower and middle Curtis are linked to sand fluid over­pressure within a remobilized sandy substratum, potentially triggered by seismic activity. Furthermore, the occurrence of a sub-regional angular relationship between the middle Curtis and substratum implies that the area of study was impacted by a regional deformational event during the Late Jurassic, before the deposition of the middle Curtis. The spatial distribution of these sub-units supports the distinction of three different sectors across the study area: sector 1 in the north, sector 2 in the south-southwest, and sector 3 in the east. In sector 1, the Curtis For­mation is represented by its three sub-units, whereas sector 2 is dominated by the middle and upper Curtis, and sector 3 encompasses the extent of the Moab Member of the Curtis Formation. This study also highlights the composite nature of the J-3 unconformity, which was impacted by various processes occurring before the Curtis Formation was deposited, as well as during the development of the lower and middle Curtis. Local collapse features within the lower and middle Curtis are linked to sand fluid over­pressure within a remobilized sandy substratum, potentially triggered by seismic activity. Furthermore, the occurrence of a sub-regional angular relationship between the middle Curtis and substratum implies that the area of study was impacted by a regional deformational event during the Late Jurassic, before the deposition of the middle Curtis.

Floristic Survey of Summer Aspect in Chosen China Clay Pits in Western Bohemia

Five different china clay pits in the western part of the Czech Republic were explored and plant species were determined. These chosen pits were: Hájek-western part, Chlumčany, Horní Bříza, Otovice and Podlesí II. China clay pits with active excavation represent a specific environment concerning both physical and chemical characteristics. This article is presenting a list of the higher plants which were found within active excavation or former excavation areas. Species with a protection status according to the Czech legislation are presented in more detail. 189 different species have been found in total, including 2 species from category C4 – potentially vulnerable taxa, 6 species from category C3 – endangered taxa and 1 species from the C1 – critically threatened taxa from the Red List of Vascular Plants of the Czech Republic. 28 different species occurred at each of the five sites. Predominant species favour sandy substratum and bare surface.

Human activity and aeolian relief of Starczynów “Desert”, Poland

Starczynów „Desert” is located in the eastern part of the Silesian Upland (southern Poland) and makes a compact area with the occurrence of aeolian sands, which till the 1960s. were intensively blown. Its flat surface is diversified by many dunes of different shapes and sizes. Aeolian coversands are formed here as a cover of changing thickness. The „desert” is not a typical dry climatic area. The term Starczynów „Desert” refers to the area of occurrence of bare sands and aeolian processes and makes a geographical name that can be found on topographic maps. Its development was conditioned by human activity, where since the Middle Ages dense forest areas have been cut to obtain timber for the needs of contemporary mining and metallurgy of lead and silver ores causing the activation of aeolian processes at sandy substratum, built from the Vistulian proluvial-deluvial deposits. In the formation of the aeolian relief of Starczynów „Desert” it is possible to distinguish some stages of intensive wind activity: the 13th-15th centuries, the 16th-17th centuries, the turn of 18th and 19th centuries, the turn of 20th and 21st centuries. In present times human interference in the environment of Starczynów „Desert” consists of fixing sandy areas to protect them from deflation. Human damage exists here in the aeolian relief through terrain levelling and building fire escape roads. In the north-eastern part of the „desert” sand was exploited, therefore a sandpit appeared. This area was subject to the activity of mining for Zn-Pb ores, which caused numerous collapsed cones. In the last few years this part of the „desert” was properly reclaimed.

Monitoring of Large Section Tunnel Crossing Qiantang River during Operation Period

The foreign precision monitoring equipment was used for long term health monitoring in the large diameter tunnel of Hangzhou Qingchun-road. Based on field monitoring data, the force and deformation of the large section crossing-river tunnel during operation period were summarized and analyzed. A detailed analysis of the effect of tide and scour on the tunnel interface force and tunnel settlement were given. Data shows accumulations of both longitudinal settlement of tunnel segments and the earth pressure distribution around the tunnel lining under the loads of both traffic and tide which results in soil disturbance in the construction period. The settlement becomes stable after about six months. The substratum has a great influence on the longitudinal settlement of tunnel segments. The settlement of tunnel invert in sandy substratum is obviously affected by the tide of Qiantang River for short time, while slight changes appear in the deformation of tunnel diameter, stress of steel bar and earth pressure distribution.

Discriminating between Posidonia oceanica meadows and sand substratum using multibeam sonar

Di Maida, G., Tomasello, A., Luzzu, F., Scannavino, A., Pirrotta, M., Orestano, C., and Calvo, S. 2011. Discriminating between Posidonia oceanica meadows and sand substratum using multibeam sonar. – ICES Journal of Marine Science, 68: 12–19. High-resolution, multibeam sonar (MBS) (455 kHz) was used to identify two typologies of seabed 8 m deep: Posidonia oceanica meadow and sandy substratum. The results showed that the heterogeneity of the architecture of the P. oceanica canopy and the relatively simple morphology of a sandy substratum can be detected easily by statistical indices such as standard deviation or range-of-beam depth. Based on these indices, an automated classification was performed for seabed mapping. The overall classification accuracy was as high as 99 and 98% in October and January, respectively. The probability that P. oceanica in situ was omitted on the map was <7%, whereas the probability that an area classified as P. oceanica on the map did not correspond to the seagrass in situ was consistently negligible. Based on these results, high-resolution MBS can be considered to be an accurate tool for mapping P. oceanica and sand substrata, and its discriminating power seems to be independent of season (autumn or winter).