Articoli di riviste: "Lachlan River (N.S.W.)"

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Wilkins, Colin, e Mike Quayle. "Structural Control of High-Grade Gold Shoots at the Reward Mine, Hill End, New South Wales, Australia". Economic Geology 116, n. 4 (1 giugno 2021): 909–35. http://dx.doi.org/10.5382/econgeo.4807.

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Abstract The Reward mine at Hill End hosts structurally controlled orogenic gold mineralization in moderately S plunging, high-grade gold shoots located at the intersection between a late, steeply W dipping reverse fault zone and E-dipping, bedding-parallel, laminated quartz veins (the Paxton’s vein system). The mineralized bedding-parallel veins are contained within the middle Silurian to Middle Devonian age, turbidite-dominated Hill End trough forming part of the Lachlan orogen in New South Wales. The Hill End trough was deformed in the Middle Devonian (Tabberabberan orogeny), forming tight, N-S–trending, macroscopic D2 folds (Hill End anticline) with S2 slaty cleavage and associated bedding-parallel veins. Structural analysis indicates that the D2 flexural-slip folding mechanism formed bedding-parallel movement zones that contained flexural-slip duplexes, bedding-parallel veins, and saddle reefs in the fold hinges. Bedding-parallel veins are concentrated in weak, narrow shale beds between competent sandstones with dip angles up to 70° indicating that the flexural slip along bedding occurred on unfavorably oriented planes until fold lockup. Gold was precipitated during folding, with fluid-flow concentrated along bedding, as fold limbs rotated, and hosted by bedding-parallel veins and associated structures. However, the gold is sporadically developed, often with subeconomic grades, and is associated with quartz, muscovite, chlorite, carbonates, pyrrhotite, and pyrite. East-west shortening of the Hill End trough resumed during the Late Devonian to early Carboniferous (Kanimblan orogeny), producing a series of steeply W dipping reverse faults that crosscut the eastern limb of the Hill End anticline. Where W-dipping reverse faults intersected major E-dipping bedding-parallel veins, gold (now associated with galena and sphalerite) was precipitated in a network of brittle fractures contained within the veins, forming moderately S plunging, high-grade gold shoots. Only where major bedding-parallel veins were intersected, displaced, and fractured by late W-dipping reverse faults is there a potential for localization of high-grade gold shoots (>10 g/t). A revised structural history for the Hill End area not only explains the location of gold shoots in the Reward mine but allows previous geochemical, dating, and isotope studies to be better understood, with the discordant W-dipping reverse faults likely acting as feeder structures introducing gold-bearing fluids sourced within deeply buried Ordovician volcanic units below the Hill End trough. A comparison is made between gold mineralization, structural style, and timing at Hill End in the eastern Lachlan orogen with the gold deposits of Victoria, in the western Lachlan orogen. Structural styles are similar where gold mineralization is formed during folding and reverse faulting during periods of regional east-west shortening. However, at Hill End, flexural-slip folding-related weakly mineralized bedding-parallel veins are reactivated to a lesser degree once folds lock up (cf. the Bendigo zone deposits in Victoria) due to the earlier effects of fold-related flattening and boudinage. The second stage of gold mineralization was formed by an array of crosscutting, steeply W dipping reverse faults fracturing preexisting bedding-parallel veins that developed high-grade gold shoots. Deformation and gold mineralization in the western Lachlan orogen started in the Late Ordovician to middle Silurian Benambran orogeny and continued with more deposits forming in the Bindian (Early Devonian) and Tabberabberan (late Early-Middle Devonian) orogenies. This differs from the Hill End trough in the eastern Lachlan orogen, where deformation and mineralization started in the Tabberabberan orogeny and culminated with the formation of high-grade gold shoots at Hill End during renewed compression in the early Carboniferous Kanimblan orogeny.

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ERWIN, TERRY L. "The beetle family Carabidae of Costa Rica: The genus Epikastea Liebke of the Plochonida Group, with new Neotropical species and notes on their way of life (Insecta: Coleoptera, Lebiini, Agrina)". Zootaxa 790, n. 1 (22 dicembre 2004): 1. http://dx.doi.org/10.11646/zootaxa.790.1.1.

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Genus Epikastea Liebke 1936, of the Plochionida Group of Subtribe Agrina, Lebiini, with six species is revised. Subtribe Agrina consists of those species formerly included in the Subtribe Calleidina. The species of Epikastea Liebke 1936 are diagnosed, described, and illustrated. One species occurs in Costa Rica; five are new South American species and are here assigned to this genus. The five new species described are: Epikastea biolat Erwin, n. sp. (PER , MADRE DE DIOS, Rio Manu, BIOLAT Biodiversity Station, Pakitza Guard Station, 356m, 11 56 47 S, 071 17 00 W), Epikastea grace Erwin, n. sp. (PER , LORETO, Samiria River, Camp Manco Capac, 04 43 0 S, 074 18 0 W), Epikastea mancocapac Erwin, n. sp. (PER , LORETO, Samiria River, Camp Manco Capac, 04 43 0 S, 074 18 0 W), Epikastea piranha Erwin, n. sp. (ECUADOR. ORELLANA, Hauorani Territory, Camp Pira a, 0 39' 25.685" S, 76 27' 10.813" W), Epikastea poguei Erwin, n. sp. (PER , MADRE DE DIOS, Rio Manu, BIOLAT Biodiversity Station, Pakitza Guard Station, 356m, 11 56 47 S, 071 17 00 W). A definition of the Plochionida Group and an identification key to the Western Hemisphere genera included are provided. A key to the known species of Epikastea Liebke is given. Distribution data are provided for all species and a map is provided for the Costa Rican taxon. Adults of Epikastea Liebke have been found on rotting logs in rainforests and fogged from the canopy of tropical trees and palms.

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Yang, Suhang, Jie Liang, Xiaodong Li, Yuru Yi, Ziqian Zhu, Xin Li, Xuwu Chen, Shuai Li, Yeqing Zhai e Ziming Pei. "The Impacts of Hydrology and Climate on Hydrological Connectivity in a Complex River–Lake Floodplain System Based on High Spatiotemporal Resolution Images". Water 14, n. 12 (7 giugno 2022): 1836. http://dx.doi.org/10.3390/w14121836.

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The drivers that determine the hydrological connectivity (HC) are complex and interrelated, and disentangling this complexity will improve the administration of the river–lake interconnection system. Dongting Lake, as a typical river–lake interconnected system, is freely connected with the Yangtze River and their HC plays a major role in keeping the system healthy. Climate, hydrology, and anthropogenic activities are associated with the HC. In this study, hydrological drivers were divided into the total flow of three inlets (T-flow) and the total flow of four tributaries (F-flow). To elucidate the HC of the Dongting Lake, HC was calculated by geostatistical methods in association with Sentinel-2 remote sensing images. Then, the structural equation model (SEM) was used to quantify the impacts of hydrology (F-flow, and T-flow) and meteorology (precipitation, evaporation, and temperature) on HC. The geostatistical analysis results demonstrated that the HC showed apparent seasonal change. For East and West Dongting Lake, the dominant element was north–south hydrological connectivity (N–S HC), and the restricted was west–east hydrological connectivity (W-E HC), but the dominant element was E–W HC and the restricted was N–S HC in South Dongting Lake. The results of SEM showed that N–S HC was mainly explained by T-flow (r = 0.49, p < 0.001) and F-flow (r = 0.28, p < 0.05). T-flow, temperature (r = 0.33, p < 0.05), and F-flow explained E–W HC. The finding of this work supports the management of both the Dongting Lake floodplain and other similar river–lake floodplain systems.

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Campos, Paula Nepomuceno, Rosildo Santos Paiva, Ana Cristina Teixeira Bonecker, Nuno Filipe Alves Correia de Melo, Glauber David Almeida Palheta, Cristiane Teixeira Contente e Caio Aguiar Rodrigues Ramos. "First occurrence of Dolicholagus longirostris larvae (Maul 1948) (Osmeriformes, Bathylagidae) near the mouth of the Amazon River". Biota Neotropica 7, n. 1 (2007): 217–19. http://dx.doi.org/10.1590/s1676-06032007000100026.

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The family Bathylagidae contains eight genera and 22 species, of which only five occur in the Southwest Atlantic. Until recently, only adult specimens of the bathylaginin Melanolagus bericoides had been recorded off southern Brazil, between the Santa Marta Cape and Rio Grande (31° S and 49° W). The present work reports the first occurrence of Dolicholagus longirostris larvae on the northern Brazilian coast, expanding its distribution in the Southwest Atlantic. The two specimens found were collected near the mouth of the Amazon River (02° 00' 19" N, 47° 03' 30" W, and 00° 49' 06" N, 46° 25' 09" W).

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GARRISON, ROSSER W., e NATALIA VON ELLENRIEDER. "New species of the damselfly genus Argia from Mexico, Central America and Ecuador with an emphasis on Costa Rica (Insecta: Odonata: Coenagrionidae)". Zootaxa 4235, n. 1 (20 febbraio 2017): 1. http://dx.doi.org/10.11646/zootaxa.4235.1.1.

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Seven new species of Argia are described, five of which occur in Costa Rica: Argia calverti n. sp. (Holotype ♂, Costa Rica, Cartago Prov., Tapantí Reserve, 1,310 m, 6 vii 1963, F. G. Thompson leg., in FSCA); Argia carolus n. sp. (Holotype ♂, Costa Rica, San José Prov., El Rodeo Biological Reserve, 7 km W of Villa Colón, 9°54' N, 84°16' W, 561 m, 10–13 vii 1990, T. W. Donnelly leg., in FSCA); Argia elongata n. sp. (Holotype ♂, Costa Rica, Cartago Prov., Reventazón river, SE of Turrialba by highway 10, 9°52'56'' N, 83°38'49'' W, 561 m, 10 viii 1979, R. W. & J. A. Garrison leg., in CSCA); Argia haberi n. sp. (Holotype ♂, Costa Rica, San José Prov., Bosque del Tolomuco, km 118 on Pan American highway, in seeps and trickles through brushy pasture on forested hillside, 9°28'18'' N, 83°41'48'' W, 1,710 m, 27 iii 2006, F. Sibley leg., in FSCA); Argia schorri n. sp. (Holotype ♂, Costa Rica, Puntarenas Prov., 2.8 mi E of Golfito, 8°39' N, 83°7' W, 35 m, 4 vii 1967, O. S. Flint, Jr. & M. A. Ortiz B. leg., in USNM), and two which are so far only known from Mexico and Ecuador respectively: Argia rudolphi n. sp. (Holotype ♂, Mexico, Puebla State, Zihuateutla, Sierra de Huauchinango, La Unión, in drainage area, 20°14'25'' N, 97°53'38'' W, 596 m, 21 v 1987, R. Novelo & A. Gómez leg., in CSCA) and Argia schneideri n. sp. (Holotype ♂, Ecuador, Napo Prov., Las Palmas, on Anzu river in Napo river watershed, 11 xii 1936, W. Clark-MacIntyre leg., in UMMZ). All the new species, as well as closely related species needed for diagnosis including A. anceps Garrison, A. cupraurea Calvert, A. cuprea (Hagen), A. extranea (Hagen), A. fissa Selys, A. fulgida Navás, A. oenea Hagen in Selys, A. popoluca Calvert, A. rhoadsi Calvert, and A. westfalli Garrison, are illustrated and diagnosed from their congeners and their known distribution areas are mapped.

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Jung, Thomas S., Troy D. Pretzlaw e David W. Nagorsen. "Northern Range Extension of the Pygmy Shrew, Sorex hoyi, in the Yukon". Canadian Field-Naturalist 121, n. 1 (1 gennaio 2007): 94. http://dx.doi.org/10.22621/cfn.v121i1.402.

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A Pygmy Shrew, Sorex hoyi, was captured in a pitfall trap on the Blackstone River (65°04.6'N, 138°10.8'W) in central Yukon. This represents a northern range extension of about 110 km for S. hoyi in the Yukon.

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Miller, J. J., T. W. Curtis, E. Bremer, D. S. Chanasyk e W. D. Willms. "Evaluation of selected soil properties for indicating cattle activity at off-stream watering and river access sites in southern Alberta". Canadian Journal of Soil Science 93, n. 3 (agosto 2013): 343–58. http://dx.doi.org/10.4141/cjss2012-074.

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Miller, J. J., Curtis, T. W., Bremer, E., Chanasyk, D. S. and Willms, W. D. 2013. Evaluation of selected soil properties for indicating cattle activity at off-stream watering and river access sites in southern Alberta. Can. J. Soil Sci. 93: 343–358. Off-stream watering troughs may reduce surface water pollution by shifting nutrient distribution from natural watering sites along the river to around artificial water troughs some distance from the river. The objective of our study was to evaluate the suitability of nine soil properties for assessing the impacts of cattle activity adjacent to eight watering sites. Nine surface (0–5 cm) soil properties were evaluated along four 100-m transects at the five off-stream water troughs and three river access sites along the Lower Little Bow River in southern Alberta over 4 yr (2007–2010). The properties included P (total P, soil test P or STP), N (total N, NO3-N, NH4-N), total C, total C:total N ratio (TC:TN), chloride (Cl), and soil bulk density. Soil test P was significantly (P≤0.05) enriched at 65% of site-year comparisons, followed by total C (63%), NO3-N (55%), total P and TC:TN (50%). This suggested that these soil properties were relatively good indicators of cattle activity at the majority (>50%) of watering sites. Chloride was a valid indicator only in non-saline areas (100% of four non-saline sites). Total C and TC:TN ratios were not valid indicators in the calcareous soils at all sites because of possible confounding influence of inorganic C. Overall, we recommend Cl as an indicator of cattle activity at watering sites not affected by soil salinity and high natural Cl levels, and STP as the best overall indicator of cattle activity at off-stream watering sites and river access sites. Certain soil properties were also influenced by distance from watering site, stocking rate, precipitation, and age of water trough.

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Fettuccia, D. C., V. M. F. da Silva, M. S. Rocha e P. C. Simões-Lopes. "Sternum and appendicular skeleton: morphometric differences between the species of genus Sotalia (Cetacea: Delphinidae)". Journal of the Marine Biological Association of the United Kingdom 92, n. 8 (31 agosto 2012): 1657–62. http://dx.doi.org/10.1017/s0025315412000604.

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Two distinct species have been recently recognized for the genus Sotalia: S. fluviatilis, occurring in the Amazon River basin, and S. guianensis, from Honduras (15°58′N and 85°42′W) to Santa Catarina State (Florianópolis, southern Brazil—27°35′S and 48°34′W). For the first time the sternum and the appendicular skeleton of the two species of the genus Sotalia are compared. A comparative osteological work was performed with marine samples (from the States of Ceará, north-eastern and Santa Catarina, southern regions of Brazil) and riverine samples (Amazonas State) in relation to metric characters (scapula, flipper and sternum). There was a clear distinction of two species in relation to postcranial skeleton in the morphometric analysis (canonical variate analysis) presented. The flipper and the glenoid cavity of the scapula were proportionally wider in the fluvial species. The sternum, however, was smaller in this species in relation to the maximum width of the manubrium. Nevertheless, this structure still needs to be further studied.

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KANE, R. P. "Inter-annual variability of rainfalls in the Amazon basin and its vicinity". MAUSAM 58, n. 3 (26 novembre 2021): 351–60. http://dx.doi.org/10.54302/mausam.v58i3.1330.

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An analysis of the rainfall series (12-month running means) of the 5° × 5° gridded data in the Amazon river basin and its vicinity (15° N – 20° S, 30° - 80° W) indicated that the rainfalls were highly variable both from year to year and from region to region. Correlations with even nearby regions hardly exceeded 0.50, though correlations were better (up to 0.70) in the regions near the eastern coast of Brazil. Moderate relationship with ENSO indices was obtained for the Amazon river basin and the regions to its north, and for NE Brazil, while moderate relationship with South Atlantic SST was obtained for NE Brazil and the region immediately to its west. All other relationships (with 30 hPa wind, North Atlantic Oscillation Index, etc.) were obscure.

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PECK, STEWART B., e JOYCE COOK. "Systematics, distributions and bionomics of the Catopocerini (eyeless soil fungivore beetles) of North America (Coleoptera: Leiodidae: Catopocerinae)". Zootaxa 3077, n. 1 (28 ottobre 2011): 1. http://dx.doi.org/10.11646/zootaxa.3077.1.1.

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This paper is a review and revision of the tribe Catopocerini (Coleoptera: Leoididae: Catopocerinae) of North America. It covers the following genera: Catopocerus Motschulsky, 1870 with five species east of the Mississippi River and the resurrected genus Pinodytes Horn, 1880 with 42 species in North America west of the Mississippi River. All species in the tribe are eyeless and wingless inhabitants of forest soil and litter. Larvae and adults probably feed on subterranean fungi. Pinodytes Horn is resurrected to valid generic status. A neotype is assigned for Catopocerus politus Motschulsky. Lectotypes are designated for Catops cryptophagoides (Mannerheim, 1852) (which is transferred to Pinodytes), and Pinodytes pusio Horn, 1892. The following new synonym is recognized: Catopocerus ulkei Brown, 1933 = Catopocerus politus Motschulsky, 1870. The 33 new species and their distributions are as follows: Pinodytes angulatus (NW Oregon, USA), P. borealis (central Alaska, USA), P. chandleri (N California, USA), P. colorado (Colorado, USA), P. constrictus (S California, USA), P. contortus (E California, USA), P. delnorte (NW California, USA), P. eldorado (E California, USA), P. fresno (central California, USA), P. garibaldi (NW Oregon, USA), P. gibbosus (S California, USA), P. haidagwaii (Haida Gwaii (formerly Queen Charlotte) Islands, British Columbia, Canada), P. humboldtensis (NW California, USA), P. idaho (NW Idaho, USA), P. isabella (N Idaho, USA), P. klamathensis (SW Oregon and NW California, USA), P. losangeles (S California, USA), P. marinensis (W California, USA), P. minutus (central California, USA), P. monterey ( SW California, USA), P. newtoni (Ozarks region to E Texas, USA), P. orca (SW Oregon, USA), P. parvus (NW California, USA), P. punctatus (W Idaho and E Washington, USA), P. sanjacinto (S California, USA), P. sequoia ( S central California, USA), P. setosus ( SW Oregon and NW California, USA), P. shasta (N California, USA), P. shoshone (N Idaho, USA), P. sinuatus (SW Oregon, USA), P. spinus (N central California, USA), P. tehama (N California, USA), and P. tuolumne (E central California, USA). The following new combinations are established: Pinodytes capizzii (Hatch, 1957), ex Catopocerus; P. cryptophagoides (Mannerheim, 1852), ex Catopocerus; P. imbricatus (Hatch, 1957), ex Catopocerus; P. newelli (Hatch, 1957), ex Catopocerus; P. ovatus (Hatch, 1957), ex Catopocerus; P. pusio Horn, 1892, ex Catopocerus; P. rothi (Hatch, 1957), ex Catopocerus; P. subterraneus (Hatch, 1935), ex Catopocerus; P. tibialis (Hatch, 1957), ex Catopocerus.

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Zhang, Lifeng, Zhiguang Chen, Xiang Zhang, Liang Zhao, Qi Li, Dongdong Chen, Yanhong Tang e Song Gu. "Evapotranspiration and Its Partitioning in Alpine Meadow of Three-River Source Region on the Qinghai-Tibetan Plateau". Water 13, n. 15 (29 luglio 2021): 2061. http://dx.doi.org/10.3390/w13152061.

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The Qinghai-Tibetan Plateau (QTP) is generally considered to be the water source region for its surrounding lowlands. However, there have only been a few studies that have focused on quantifying alpine meadow evapotranspiration (ET) and its partitioning, which are important components of water balance. This paper used the Shuttleworth–Wallace (S–W) model to quantify soil evaporation (E) and plant transpiration (T) in a degraded alpine meadow (34°24′ N, 100°24′ E, 3963 m a.s.l) located at the QTP from September 2006 to December 2008. The results showed that the annual ET estimated by the S–W model (ETSW) was 511.5 mm (2007) and 499.8 mm (2008), while E estimated by the model (ESW) was 306.0 mm and 281.7 mm for 2007 and 2008, respectively, which was 49% and 29% higher than plant transpiration (TSW). Model analysis showed that ET, E, and T were mainly dominated by net radiation (Rn), while leaf area index (LAI) and soil water content at a 5 cm depth (SWC5cm) were the most important factors influencing ET partitioning. The study results suggest that meadow degradation may increase water loss through increasing E, and reduce the water conservation capability of the alpine meadow ecosystem.

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Cotrim da Cunha, L., e E. T. Buitenhuis. "Riverine influence on the tropical Atlantic Ocean biogeochemistry". Biogeosciences Discussions 9, n. 2 (17 febbraio 2012): 1945–69. http://dx.doi.org/10.5194/bgd-9-1945-2012.

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Abstract. We assess the role of riverine inputs of N, Si, Fe, organic and inorganic C in the tropical Atlantic Ocean using a global ocean biogeochemistry model. We use two sensitivity tests to investigate the role of the western (South American Rivers) and eastern (African Rivers) riverine nutrient inputs on the tropical Atlantic Ocean biogeochemistry (between 20° S–20° N and 70° W–20°). Increased nutrient availability from river inputs in this area (compared to an extreme scenario with no river nutrients) leads to an increase in 14 % (0.7 Pg C a−1) in open ocean primary production (PP), and 21 % (0.2 Pg C a−1) in coastal ocean PP. We estimate very modest increases in open and coastal ocean export production and sea-air CO2 fluxes. Results suggest that in the tropical Atlantic Ocean, the large riverine nutrient inputs on the western side have a larger impact on primary production and sea-air CO2 exchanges. On the other hand, African river inputs, although smaller than South American inputs, have larger impact on the coastal and open tropical Atlantic Ocean export production. This is probably due to a combination of nutrient trapping in upwelling areas off the Congo River outflow, and differences in delivered nutrient ratios leading to alleviation in limitation conditions mainly for diatoms.

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ΓΑΛΑΝΑΚΗΣ, Δ. "Brittle tectonic and morphological alteration of Almyros basin". Bulletin of the Geological Society of Greece 34, n. 1 (1 gennaio 2001): 371. http://dx.doi.org/10.12681/bgsg.17038.

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Two crossed fault systems with NW-SE and E-W directions affect on the central and southern part of the Almyros basin. The uplift movement in the western part of the basin, with importance vertical displacement (up to 200m) of the lignite layers and the formation river terraces are related with the activity of the first fault NWSE direction. The second fault with E-W direction, located along Xerias river, affect on drainage system with hydrographie network from the south to the north development. In the southern part of the basin and on the Orthrys mountain a fault system with E-W trending affects on alpine basement and neogene deposits. This fault system forms the southern boundary of the Almyros basin. The recent brittle tectonic during Neogene-Quaternary is connected with the evolution and the configuration of the Almyros basin as well as volcanic activity of the area. The morphological differentiations of Almyros basin, the drainage system and the recent landforms with morphogenic activity are controlled by the recent brittle tectonics. The normal fault systems in the studied area caused by the extensional stress field (σ3), trending N-S to NNW-SSE, which controls the geodynamic regime since Lower Pleistocene. This geodynamic regime has defined the recent morphological and morphotectonic evolution of the studied area.

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Martell, Mark S., Charles J. Henny, Peter E. Nye e Matthew J. Solensky. "Fall Migration Routes, Timing, and Wintering Sites of North American Ospreys as Determined by Satellite Telemetry". Condor 103, n. 4 (1 novembre 2001): 715–24. http://dx.doi.org/10.1093/condor/103.4.715.

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Abstract Satellite telemetry was used to determine fall migratory movements of Ospreys (Pandion haliaetus) breeding in the United States. Study areas were established along the lower Columbia River between Oregon and Washington; in north-central Minnesota; on Shelter Island, New York; and in southern New Jersey. Seventy-four adults (25 males, 49 females) were tracked from 1995 through 1999. Migration routes differed among populations but not by sex. Western Ospreys migrated through California and to a lesser degree other western states and wintered in Mexico (88%), El Salvador (6%), and Honduras (6%) (25.9°N to 13.0°N and 108.3°W to 87.3°W). Minnesota Ospreys migrated along three routes: (1) through the Central U.S. and then along the east coast of Mexico, (2) along the Mississippi River Valley, then across the Gulf of Mexico, or (3) through the southeastern U.S., then across the Caribbean. East Coast birds migrated along the eastern seaboard of the U.S., through Florida, and across the Caribbean. Midwestern birds wintered from Mexico south to Bolivia (22.35°N to 13.64°S, and 91.75°W to 61.76°W), while East Coast birds wintered from Florida to as far south as Brazil (27.48°N to 18.5°S and 80.4°W to 57.29°W). Dates of departure from breeding areas differed significantly between sexes and geographic regions, with females leaving earlier than males. Western birds traveled a shorter distance than either midwestern or eastern Ospreys. Females traveled farther than males from the same population, which resulted in females typically wintering south of males. Rutas de Migración Otoñales, Coordinación y Sitios de Invernada de Pandion haliaetus Determinados por Telemetría Satelital Resumen. Se utilizó telemetría satelital para determinar los movimientos de migración de otoño de individuos de Pandion haliaetus que nidifican en los Estados Unidos. Las áreas de estudio se establecieron a lo largo del Río Columbia entre Oregon y Washington; en el centro-norte de Minnesota; en la Isla Shelter, Nueva York; y en el sur de Nueva Jersey. Setenta y cuatro adultos (25 machos, 49 hembras) fueron seguidos mediante telemetría desde 1995 hasta 1999. Las rutas de migración se diferenciaron entre poblaciones pero no entre sexos. Los individuos de P. haliaetus del oeste, migraron a través de California y en menor grado a través de otros estados del oeste e invernaron en México (88%), El Salvador (6%) y Honduras (6%) (25.9°N a 13.0°N y 108.3°O a 87.3°O). Las aves de Minnesota migraron a lo largo de tres rutas: (1) a través del los E.E.U.U. centrales y luego a lo largo de la costa este de México, (2) a lo largo del valle del Río Mississippi y luego a través del Golfo de México, o (3) a través del sur de los E.E.U.U. y luego a través del Caribe. Las aves de la costa este, migraron a lo largo de la costa este de los E.E.U.U., por Florida y a través del Caribe. Las aves del medio-oeste, invernaron desde México hacia el sur hasta Bolivia (22.35°N a 13.64°S, y 91.75°O a 61.76°O), mientras que las aves de la costa este invernaron desde Florida hasta tan al sur como Brasil (27.48°N a 18.5°S y 80.4°O a 57.29°O). Las fechas de partida desde las áreas de nidificación difirieron significativamente entre sexos y regiones geográficas, partiendo las hembras antes que los machos. Las aves del oeste viajaron distancias más cortas que las aves del medio-oeste y del este. Considerando una misma población, las hembras viajaron más lejos que los machos, lo que resultó en que las hembras invernaron típicamente más al sur que los machos.

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Santos, M. D., e M. C. Brasil-Sato. "Parasitic community of Fransciscodoras marmoratus (Reinhardt, 1874) (Pisces: Siluriformes, Doradidae) from the upper São Francisco river, Brazil". Brazilian Journal of Biology 66, n. 3 (agosto 2006): 931–38. http://dx.doi.org/10.1590/s1519-69842006000500019.

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One hundred and thirteen specimens of Franciscodoras marmoratus (Reinhardt, 1874) were collected in the upper São Francisco River (18° 12' 32" S, 45° 15' 41" W, state of Minas Gerais) between September, 1999 and January, 2004 to investigate their parasite fauna. From this total, 45 (39.8%) were afflicted by at least one parasite species. The parasitic richness consisted of six species represented by Hirudinea (n = 20), Monogenoidea (n = 25), Eucestoda (n = 55), Nematoda (n = 1, n = 2) and Acanthocephala (n = 41) found in the dry and wet periods making a total of 144 specimens. Proteocephalus renaudi Chambrier & Vaucher, 1994 was the only species with prevalence higher than 10% and a typical aggregate distribution pattern. The prevalence, intensity and abundance of P. renaudi were not influenced by the total length or sex of the hosts or by the collection periods. The relative condition factor indicated that the health of the P. renaudi hosts was not significantly affected in relation to fish not infected by parasites. The fish stocked in tanks before necropsy were opportunistically infested by Lernaea cyprinacea Yashuv, 1959. The various parasites found indicate that F. marmoratus is omnivorous and a potential definitive host. The parasite species, except for Acanthocephala, have expanded their known geographic distribution to the São Francisco River Basin. The parasite community was considered isolationist because of the low endoparasite diversity, infrapopulations with low intensity, lack of evidence of parasite interactions and sparse signs of parasite aggression against their hosts.

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16

Vieira, João P. "Ecological analogies between estuarine bottom trawl fish assemblages from Patos Lagoon, Rio Grande do Sul, Brazil and York River, Virginia, USA". Revista Brasileira de Zoologia 23, n. 1 (marzo 2006): 234–47. http://dx.doi.org/10.1590/s0101-81752006000100017.

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The structure of estuarine fish assemblages at temperate latitudes in Patos Lagoon (32º05'S, 52º04'W), Rio Grande do Sul, Brazil and York River (37º17'N, 76º33'W), Virginia, USA was compared using mid and late 1970's data from bottom trawl collection to investigate whether geographically isolated fish assemblages have similar ecological structure given similar latitudinal positions on the warmtemperate southwestern and northwestern Atlantic regions, respectively. Since estuarine species often exhibit an ontogenetic shift in habitat requirements or preferences we examined Capture per Unity of Effort by size class (CPUE-SC) and split species into "size ecological taxa" (SET) for analysis. The use of CPUE-SC also allowed the abundance of a SET to be computed by summing the mean CPUE of each size class within that SET and use this information to follows SET's temporal and or spatial abundance. A total of 65 and 63 species was collected during a year of bottom trawling in the Patos Lagoon and York River estuaries, respectively. In both localities the strongest modal size class was < 80 mm TL, and several abundant species were smaller than 100 mm TL. The size between 80 and 100 TL effectively separated several species into discrete SET's in both systems. Those SET's could have different ecological preferences, temporal and spatial distributions and so identified as different "ecological taxa". In warm months, when predation by large fish is most likely, the abundance of fish between 80 and 100 mm TL in "bottom trawl" demersal fish assemblages was low in both systems. Only the sea catfishes, in Patos Lagoon, protected by strong dorsal and pectoral spines, and the Hogchoker, in the York River, protected by burrowing in the bottom substrate, peak in abundance at this size class. The seasonal pattern of estuarine use was similar between localities and did not differ from other warm-temperate estuarine fish assemblages.

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17

Setyawan, E. Y., S. Djiwo, D. H. Praswanto, P. Suwandono e P. Siagian. "Design of Low Flow Undershot Type Water Turbine". JOURNAL OF SCIENCE AND APPLIED ENGINEERING 2, n. 2 (28 novembre 2019): 50. http://dx.doi.org/10.31328/jsae.v2i2.1184.

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Many water sources around us which have kinetic energy to run waterwheels are not optimally utilized. This energy can be converted into an energy source that can produce electricity. Therefore this study produced a design of a waterwheel that could be used in low-flow rivers to produce electricity by adding generators. Waterwheel modeling using Ansys is calculated based on flow assumptions. Modeling using this system provides advantages in the form of computational power efficiency, the stability of numerical calculations and the accuracy of the resulting solutions. Numerical analysis of the waterwheel is assumed that the waterwheel is half floating on the surface of the water. As stated in the limitation of the problem that the incoming water flowing at a speed of 5 m/s from the flow moves the wheel. The flow rate of water that hit the blade on the waterwheel causes the waterwheel to rotate which is pressured by the flow of water with a number of 12 blades. With a relatively simple design, the waterwheel produces a wheel rotation I of 91 Rpm and II of 78 Rpm, with a torque of 39.2 N by using some analysis of this design can be applied to river flow with low flow velocity. The relatively simple design makes it easy to be produced and maintenance. River flow used is in the Malang District with a flow velocity of 1 m/s gets a power of 1128 W on waterwheel I while on waterwheel II gets a power of 967 W.

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18

Morriss, Matthew C., Leif Karlstrom, Morgan W. M. Nasholds e John A. Wolff. "The Chief Joseph dike swarm of the Columbia River flood basalts, and the legacy data set of William H. Taubeneck". Geosphere 16, n. 4 (14 maggio 2020): 1082–106. http://dx.doi.org/10.1130/ges02173.1.

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Abstract The Miocene Columbia River Basalt Group (CRBG) is the youngest and best studied continental flood basalt province on Earth. The 210,000 km3 of basaltic lava flows in this province were fed by a series of dike swarms, the largest of which is the Chief Joseph dike swarm (CJDS) exposed in northeastern Oregon and southwestern Washington. We present and augment an extensive data set of field observations, collected by Dr. William H. Taubeneck (1923–2016; Oregon State University, 1955–1983); this data set elucidates the structure of the CJDS in new detail. The large-scale structure of the CJDS, represented by 4279 mapped segments mostly cropping out over an area of 100 × 350 km2, is defined by regions of high dike density, up to ∼5 segments/km−2 with an average width of 8 m and lengths of ∼100–1000 m. The dikes in the CJDS are exposed across a range of paleodepths, from visibly feeding surface flows to ∼2 km in depth at the time of intrusion. Based on extrapolation of outcrops, we estimate the volume of the CJDS dikes to be 2.5 × 102–6 × 104 km3, or between 0.1% and 34% of the known volume of the magma represented by the surface flows fed by these dikes. A dominant NNW dike segment orientation characterizes the swarm. However, prominent sub-trends often crosscut NNW-oriented dikes, suggesting a change in dike orientations that may correspond to magmatically driven stress changes over the duration of swarm emplacement. Near-surface crustal dilation across the swarm is ∼0.5–2.7 km to the E-W and ∼0.2–1.3 km to the N-S across the 100 × 350 km region, resulting in strain across this region of 0.4%–13.0% E-W and 0.04%–0.3% N-S. Host-rock partial melt is rare in the CJDS, suggesting that only a small fraction of dikes were long-lived.

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19

Barbosa, Scheyla C. T., Monica F. Costa, Mário Barletta, David Valença Dantas, Helena A. Kehrig e Olaf Malm. "Total mercury in the fish Trichiurus lepturus from a tropical estuary in relation to length, weight, and season". Neotropical Ichthyology 9, n. 1 (marzo 2011): 183–90. http://dx.doi.org/10.1590/s1679-62252011000100018.

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The Goiana River Estuary (7º30'S 34º47'W) is a typical estuary of the semi-arid tropical regions. This estuary shelters a rich fauna of fish, crustaceans and mollusks which play an important role in the life of traditional populations. It is also the main recipient of the effluents from the sugarcane agro-industry and sewage from settlements and villages. Trichiurus lepturus (n = 104), from the Goiana Estuary were examined for total mercury contents during ten months (2005 to 2007) spaning two dry seasons and part of a rainy season. The studied individuals showed weight (W) (204.1±97.9 g) and total length (TL) (63.1±10.1 cm, range 29.5-89.0 cm) with a significant (p<0.05) correlation. Correlation between TL and Hg-T (r = 0.37286) and between W and Hg-T (r = 0.38212) were positive and significant (p<0.05). Two-way ANOVA (n = 81) showed that TL and W had significant difference (p<0.05) among seasons. The Hg-T showed differences in relation to the factor season (p<0.05). The correlation between Hg-T and rainfall showed a negative and significant relation (r = -0.56; p<0.05). Rainfall strongly influenced the bioacumulation of mercury in this species. Dryer months showed relatively higher mercury concentrations than the end of the rainy season. Less rainfall, and consequently less particulate matter and less primary production in the estuary, make mercury more bioavailable. Fish from this estuary are fit for human consumption at all times of the year.

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Rao, K. V., M. K. Seguin e E. R. Deutsch. "Paleomagnetism of Early Cambrian redbeds on Cape Breton Island, Nova Scotia". Canadian Journal of Earth Sciences 23, n. 9 (1 settembre 1986): 1233–42. http://dx.doi.org/10.1139/e86-120.

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Results are reported from steeply dipping red sandstones collected at nine sites (45 samples) of the Lower Cambrian Morrison River and MacCodrum formations on southeast Cape Breton Island, which forms part of the Avalon terrane. Demagnetization studies indicate minimal overlap of stability spectra in thermal, alternating-field, and chemical treatments. A stable component (hematite) with high unblocking temperatures (680 °C) is dominant at all sites. Its mean direction corrected for geologic tilt is D = 281°, I = +32°, k = 97, giving a paleomagnetic pole (pole M) at 20°N, 146°W (dp, dm = 3°, 6°). The corresponding in situ direction is D = 147°, I = +59°, k = 97, with a pole M′ at 2°S, 39°W (dp, dm = 6°, 8°). Poles M and M′ were compared with published Paleozoic poles for the Avalon Zone and cratonic North America to test whether the magnetization originated before or after the Taconic (Ordovician) folding. It could have been acquired during deposition or early diagenesis (Early to Middle Cambrian), in which case the paleolatitude differences between Morrison River–MacCodrum and age-equivalent cratonic sites require a minimum 20° post-Early Cambrian displacement between Avalon Zone and craton. This is, however, difficult to verify, since a fold test is not possible and well-dated Cambrian poles from Avalonia are lacking. Three or four of the many post-Cambrian results from the Avalon and Gander zones were found to be comparable with pole M′, so that alternatively the Morrison River–MacCodrum magnetization could be a postfolding, Late Ordovician–Early Silurian or Late Devonian overprint.

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21

Miller, J. J., T. Curtis, D. S. Chanasyk e W. D. Willms. "Influence of streambank fencing and river access for cattle on riparian zone soils adjacent to the Lower Little Bow River in southern Alberta, Canada". Canadian Journal of Soil Science 94, n. 2 (maggio 2014): 209–22. http://dx.doi.org/10.4141/cjss2013-0981.

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Miller, J. J., Curtis, T., Chanasyk, D. S. and Willms, W. D. 2014. Influence of streambank fencing and river access for cattle on riparian zone soils adjacent to the Lower Little Bow River in southern Alberta, Canada. Can. J. Soil Sci. 94: 209–222. Cattle grazing in riparian pastures adjacent to rivers may increase soil compaction and increase soil nutrients, such as N and P. We conducted a 4-yr study with sampling in 3 yr (2009, 2010, 2012) of riparian zone soils adjacent to fenced and unfenced reaches of the Lower Little Bow River in southern Alberta. We examined the effect of grazing, access of cattle to the river (access versus no-access), and distance (0.25, 1, 2, 4, 6, 8, 10 m) from the river on surface soil bulk density, volumetric water content, NH4-N, NO3, and soil test P. Penetration depth was also measured in 2012. The three grazing treatments consisted of one fenced reach (ungrazed treatment), one unfenced and grazed reach with high cattle impact (high-impact grazed treatment), and one unfenced and grazed reach with low cattle impact (low-impact grazed treatment). We hypothesized that soil compaction would be greater, soil nutrients would be enriched, and soil water content would be lower for grazed compared with ungrazed treatments, and that this same trend would occur for access compared with no-access locations. The soil properties in our study were generally significantly (P≤0.05) influenced by grazing, access, and distance from the riverbank. However, treatment effects were generally dependent on two- or three-way interactions with the other factors. Soil bulk density in 2009 and 2012 was 8 to 20% greater at access compared with no-access locations within 2 m of the riverbank, suggesting soil compaction by cattle was confined close to the wetter riverbank soils. Most soil properties generally supported our hypothesis of greater soil compaction and nutrient enrichment for unfenced compared with fenced reaches, as well as for access compared with no-access locations. The exceptions were soil water content and soil test P results that did not support the grazing hypothesis, and soil water content and NH4-N results that did not support the cattle-access hypothesis.

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da Cunha, L. C., e E. T. Buitenhuis. "Riverine influence on the tropical Atlantic Ocean biogeochemistry". Biogeosciences 10, n. 10 (9 ottobre 2013): 6357–73. http://dx.doi.org/10.5194/bg-10-6357-2013.

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Abstract. We assess the role of riverine inputs of N, Si, Fe, organic and inorganic C in the tropical Atlantic Ocean using a global ocean biogeochemistry model. We use a standard model scenario and three sensitivity tests to investigate the role of total river nutrient and carbon inputs, as well as the western (South American) and eastern (African) river inputs on the tropical Atlantic Ocean biogeochemistry, between 20° S–20° N and 70° W–20° E. Increased nutrient availability from river inputs in this area (compared to a sensitivity scenario without river nutrient inputs, NO_RIVER) leads to an increase in primary production (PP) and export production (EP), mainly in the coastal ocean area (modeled ocean area with bathymetry <200 m). Model results suggest an enhanced N-fixation by diazotrophs on the tropical Atlantic mainly in open ocean areas. The increased rate of N-fixation in the TODAY scenario is proportional to the increase in PP and EP relative to the NO_RIVER scenario, and may support up to 14% of the coastal ocean export production. Inputs from South American rivers have an impact in coastal PP and EP two times higher than those from African rivers. On the other hand, results suggest that the contribution of African and South American rivers to the total increase in open ocean PP and EP is similar. Considering the amount of delivered nutrients (2–3 times less nutrients and carbon inputs by African rivers) one concludes that African riverine inputs may have a larger impact on the whole tropical Atlantic Ocean biogeochemistry. This is probably due to a combination of nutrient trapping in upwelling areas off the large rivers' outflows and shallow mixed layers in the eastern tropical Atlantic, concomitantly to the differences in delivered nutrient ratios leading to alleviation in limitation conditions, mainly for diatoms. When river inputs are added to the model, we estimate a modest decrease in open ocean sea-air CO2 fluxes (−5.2 Tg C a−1) and an increase in coastal ocean CO2 fluxes, mainly provoked by the remineralization of riverine organic matter delivered by the South American rivers.

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IRAWATI, WAHYU, SEMUEL RIAK, NIDA SOPIAH e SUSI SULISTIA. "Heavy metal tolerance in indigenous bacteria isolated from the industrial sewage in Kemisan River, Tangerang, Banten, Indonesia". Biodiversitas Journal of Biological Diversity 18, n. 4 (7 dicembre 2017): 1481–86. http://dx.doi.org/10.13057/biodiv/d180425.

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Irawati W, Riak S, Sopiah N, Sulistia S. 2017. Heavy metal tolerance in indigenous bacteria isolated from the industrial sewage in Kemisan River, Tangerang, Banten, Indonesia. Biodiversitas 18: 1481-1486. The bacterial study is a part of human calling in preserving the earth. Many indigenous bacteria isolated from heavy metal contaminated sites had resistance to heavy metal toxicity and could be used for heavy metal removal. The aims of this study were to isolate heavy metal-tolerant indigenous bacteria from the industrial sewage of Kemisan River in Tangerang, Banten, Indonesia. The potency of bacterial isolates to remove heavy metals was also determined. The heavy-metal tolerance was determined by measuring the minimum inhibitory concentration. The potency of bacterial isolate for removing heavy metals from the medium was determined by an atomic absorption spectrophotometer. The results showed that there were eight heavy metal-resistant bacteria isolated from Kemisan River with minimum inhibitory concentration ranging from 7 mM to 11 mM. Isolate PbSI1 was the highest lead tolerant bacteria, and also tolerant to copper and zinc. The isolate was able to remove 91.25% lead, 73.38% zinc, and 98.57% copper from medium supplemented with the mixture of these heavy metals. The addition of 9 mM of lead in the medium affected the morphological appearance of isolate colonies i.e PbSI1 and PbSI3 to become darker which might occur due to the survival mechanism of bacteria by absorbing the lead inside the cells. The finding of this study indicated that isolate PbSI1 was a promising bacterium, which could be further developed for heavy metal removal.

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Dubatolov, V. V., S. K. Korb e R. V. Yakovlev. "A REVIEW OF THE GENUS TRIPHYSA ZELLER, 1858 (LEPIDOPTERA, SATYRIDAE)". Biological Bulletin of Bogdan Chmelnitskiy Melitopol State Pedagogical University 6, n. 01 (30 aprile 2016): 445–97. http://dx.doi.org/10.15421/201628.

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A review of the genus Triphysa Zeller, 1858 is presented. One new species Triphysa issykkulica sp.n. (type locality: Kazakhstan, W of Almaty, 800 m) and 8 new subspecies are described: Triphysa phryne kasikoporana ssp. n. (type locality: Kasikoporan [NE Turkey, Agri prov.]), Triphysa striatula urumtchiensis ssp. n. (type locality: Urumtchi), Triphysa issykkulica pljustchi ssp. n. (type locality: W. Kirgiziya, Talasskii Mts., Manas), Triphysa nervosa tuvinica ssp. n. (type locality: N. Tuva, near Kyzyl, Tuge Mt.), Triphysa nervosa arturi ssp. n. (type locality: S. Tuva, 15 km WSW Erzin), Triphysa nervosa kobdoensis ssp. n. (type locality: W. Mongolia, Hovd aimak, 15 km S Khara-Us-Nuur lake, 1300 m), Triphysa nervosa mongolaltaica ssp. n. (type locality: Mongolia, Hovd aimak, Bulgan-Gol basin, middle stream of Ulyasutai-Gol river, 2500−3000 m) and Triphysa nervosa brinikhi ssp. n. (type locality: Russia, Chita Reg., Onon distr., 18 km WSW Nizhniy Zasuchey vill., Butyvken lake, Pinus forest, steppe) are described. New status for Triphysa striatula Elwes, 1899, stat. n. is established. The lectotypes of Triphysa nervosa gartoki O.Bang-Haas, 1927, Triphysa phryne kintschouensis O. Bang-Haas, 1939, Triphysa phryne biocellata Staudinger, 1901, Triphysa nervosa tscherski Grum-Grshimailo, 1899 [1900], Triphysa nervosa glacialis A. Bang-Haas, 1912 are designated, the neotype of T. dohrnii Zeller, 1850 (type locality: [Russia], Sarepta) is designated.

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PERKINS, PHILIP D. "Hydraenidae of Madagascar (Insecta: Coleoptera)". Zootaxa 4342, n. 1 (3 novembre 2017): 1. http://dx.doi.org/10.11646/zootaxa.4342.1.1.

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The Madagascar fauna of the beetle family Hydraenidae is comprehensively revised, based on the study and databasing of 6,949 specimens. New collection records are provided for 11 previously described species, and 95 new species are described. Three new subgenera of Hydraena, viz. H. (Micromadraena), H. (Monomadraena), and H. (Dnahydnaedna) are described, and several new species groups of Hydraena are diagnosed. Two new genera in the tribe Madagastrini are described: Menomadraena and Trinomadraena. The Malagasy hydraenid fauna now comprises 106 species arrayed in the following nine genera: Aulacochthebius (2), Hydraena (65), Limnebius (10), Madagaster (8), Menomadraena (6), Ochthebius (1), Protozantaena (5), Sicilicula (8), and Trinomadraena (1). Lectotypes are designated for the following species: Aulacochthebius plicicollis (Fairmaire), 1898 (Ochthebius); Hydraena dilutipes Fairmaire, 1898; Hydraena impressicollis Fairmaire, 1898; Hydraena marginicollis Regimbart, 1903 (= Hydraena regimbarti Zaitzev 1908; nomen novum); and Ochthebius alluaudi Regimbart, 1903. Hydraena discicollis Fairmaire, 1898, is considered a nomen dubium: no type specimens were found, and the description appears to be that of a species of Aulacochthebius or Ochthebius, not Hydraena. High resolution digital images of lectotypes and holotypes of new species are presented (online versions in color). Male genitalia, representative antennae, maxillary palpi, and female terminal abdominal segments and spermathecae are illustrated. Geographic distributions of all species are mapped. Possible colonization and vicariance events are discussed at the tribal, generic and species group levels. The tribe Madagastrini, found only in Madagascar and southern India, is hygropetric, indicating that this microhabitat type has been continuously present in both Madagascar and India at least since the two separated, currently estimated to be 88 million years ago. Contrastingly, some lowland lentic species of other genera appear to be closely related to species in southern Africa, suggesting rather recent colonization events. New species of Aulacochthebius: A. perlaevis (Mahajanga, Boeny: Mahavavy Kinkony RS). New species of Hydraena (Micromadraena): H. breviceps (Fianarantsoa, 29 km SSW Ambositra, Ankazomivady); H. fortipes (Antsiranana, Forêt d' Antsahabe); H. genuvela (Antsiranana, Forêt de Binara); H. parvipalpis (Antananarivo, Réserve Spéciale d'Ambohitantely); H. rubridentata ((Mahajanga, Parc National de Namoroka); H. serripennis (Antsiranana, Forêt d' Antsahabe). New species of Hydraena (Monomadraena): H. acicula (Antsiranana, Antsaba, Galoko Mountains); H. ambohitantely (Antananarivo, Ambohitantely Spec. Res.); H. amplexa (Fianarantsoa, Andringitra NP); H. amplipunctata (Fianarantsoa, 7 km W Ranomafana); H. antsahabe (Antsiranana, Forêt d' Antsahabe); H. bergsteni (Antsiranana, Diana: Beraty); H. bisinuata (Toamasina, Tamatave 6.3 km S Ambanizona); H. bisinuloba (Toliara, Menabe: Kirindy RS.); H. bispica (Toamasina, Alaotra Mangoro: Analamazoatra SR); H. casacolumna (Fianarantsoa, Andringitra NP); H. compacta (Antananarivo, Ankaratra, Reserve Manjakatompo); H. contracolorata (Antsiranana, Montagne des Francais); H. epipleurata (Antsiranana, Forêt de Binara); H. furcula (Toliara, 40km N of Fort Dauphin, Managotry); H. gereckei (Antananarivo, Ankaratra, Reserve Manjakatompo); H. goldschmidti (Antananarivo, Anjozorobe, Ravoandrina); H. inseriata (Antananarivo, Anjozorobe, Ravoandrina); H. jubata (Antsiranana, Sava Marojejy NP); H. levifurcata (Fianarantsoa, Namarona River, 7 km SW Ranomafana); H. lubrica (Antananarivo, Ambohitantely Spec. Res.); H. mahavavona (Fianarantsoa, Ionilahy, Mahavavona); H. manjakatompo (Antananarivo, Ankaratra, Reserve Manjakatompo); H. marojejy (Antsiranana, Parc National de Marojejy); H. multiarcuata (Fianarantsoa, Ranomafana); H. oscillata (Toamasina, Alaotra Mangoro Andasibe-Mantadia NP); H. parvispinosa (Toamasina, Andasibe NP); H. pentarubra (Antsiranana, Montagne d'Ambre); H. quatriloba (Toliara, Andohahela NP, Tsimelahy); H. ranomafana (Fianarantsoa, Ranomafana); H. ravoandrina (Antananarivo, Anjozorobe, Ravoandrina); H. rubrifurcata (Antsiranana, Sava, Marojejy NP); H. sculponea (Antsiranana, Befingotra (9.2 km WSW), Res. Anjanaharibe-Sud); H. simplicata (Antsiranana, Montagne d'Ambre); H. tibiodentipes (Fianarantsoa, Andringitra NP); H. triaequalis (Fianarantsoa, Ranohira); H. tripartita (Fianarantsoa, Ranomena); H. upsilonica (Toamasina, Zahamena NP); New species of Hydraena (Hydraenopsis): H. andranomena (Toliara, Andranomena); H. arta (Antsiranana, Parc National de Marojejy); H. bucollis (Toamasina, Tamatave, Andranobe Field Station); H. clavulata (Fianarantsoa, Ranomafana); H. contorta (Antananarivo, Anjozorobe forest reserve); H. dilutipoides (Mahajanga, Parc National Tsingy de Bemaraha); H. divisa (Antsiranana, Antsaba,Galoko Mountains); H. elementaria (Antananarivo, Tamatave, Coastal lagoon); H. fulgidicollis (Antananarivo, Parc de Tsimbazaza); H. longiloba (Fianarantsoa, Madiorano); H. nanula (Antsiranana, Ankarana, Ampositelo); H. orchisa (Toamasina, Alaotra Mangoro Andasibe-Mantadia NP); H. pilobova (Antsiranana, Sava, Marojejy NP); H. pilotumida (Fianarantsoa, 7 km W Ranomafana); H. ranarilalatiani (Toamasina, Alaotra Mangoro: Analamazoatra SR); H. randriamihajai (Antsiranana, Diana: Montagne d'Ambre NP); H. renalisa (Antsiranana, Sambava: Marojejy NP); H. sinuatipes (Antsiranana, Ankarana); H. torquata (Fianarantsoa, Andringitra NP). New species of Limnebius: L. angulatus (Fianarantsoa, Namarona River, 7 km W Ranomafana); L. balkei (Antsiranana, Montagne d'Ambre); L. bergsteni (Fianarantsoa, Namarona River, 7 km W Ranomafana); L. clandestinus (Mahajanga, Boeny:Mahavavy Kinkony RSc); L. labratus (Toamasina, Maroantsetra); L. lacrimosus (Toamasina, 18.7911S 48.4259E Alaotra Mangoro Andasibe-Mantadia NP); L. lobatus (Toliara, Manakaravavy); L. maximadus (Toamasina, Alaotra Mangoro: Analamazoatra SR); L. nanostillus (Antsiranana, Ankarana); L. steineri (Fianarantsoa, 7 km W Ranomafana). New species of Madagaster: M. barbata (Fianarantsoa, Andringitra NP); M. bergsteni (Antananarivo, 18.8704S 47.6708E Analamanga); M. cataracta (Antsiranana, Sava, Marojejy NP); M. procarina (Fianarantsoa, 32 km S Ambositra); M. quadricurvipes (Fianarantsoa, Andringitra NP); M. simplissima (Fianarantsoa, 32 km S Ambositra). New species of Menomadraena: M. andringitra (Fianarantsoa, Res. Andringitra); M. concava (Fianarantsoa, R.S. Ivohibe); M. fisheri (Toliara, Enakara (11 km NW), Res. Andohahela); M. ivohibe (Fianarantsoa, R.S. Ivohibe); M. nitedula (Fianarantsoa, Res. Andringitra); M. sembella (Fianarantsoa, Amparihibe). New species of Protozantaena: P. duplicata (Antananarivo, Vakinankaratra: Manjakatompo Stn. Forestière); P. elongata (Antananarivo, Vakinankaratra: Manjakatompo Stn. Forestière). New species of Sicilicula: S. ampla (Antananarivo, Onive River near Ilempona); S. bergsteni (Fianarantsoa, 21.2263S 47.3694E, Matsiara Ambony, Ranomafana NP); S. conjugalis (Fianarantsoa, Namarona River, 7 km SW Ranomafana); S. cordicollis (Fianarantsoa, Namarona River, 7 km SW Ranomafana); S. hygropetrica (Fianarantsoa, Matsiara Ambony, Ranomafana NP); S. malagasica (Fianarantsoa, Abohimahasoa); S. sexplanata (Antsiranana, Mt. Tsaratanana). New species of Trinomadraena: T. clusa (Antsiranana, Mt. d’Ambre).

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26

Rashid, Bazlar, Sultan Ul Islam e Badrul Islam. "River morphology and evolution of the Barind Tract, Bangladesh". Journal of Nepal Geological Society 49, n. 1 (31 dicembre 2015): 65–76. http://dx.doi.org/10.3126/jngs.v49i1.23144.

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The Barind Tract is an elevated Pleistocene Terraces (about 11-48 mamsl) in northwestern Bangladesh and is widely accepted Tract to have been evolved from tectonic upliftment and /or exists as an erosional geomorphic feature. Some part of the Barind Tract bears the characteristics of morphological origin but some areas are providing evidences of tectonic upliftment. The present study is an attempt to interpret the morphological characteristics of the rivers in the area and tried to unveiling the processes that are responsible for the evolution of the Tract. River morphology are interpreted from satellite images and field mapping and are used to relate neotectonic activities occurred in the area. The river forms U-shaped valleys in floodplain areas whereas these are V-shaped within the Barind Tract. The rivers and valleys on the Tract are also comparatively more straight, incised and entrenched, and rivers are tightly meandered, more localized, form paired and unpaired terraces, and antecedent in nature, whereas, the rivers in the floodplain are either meandering, braided or anastomosing drainage channels. Along the boundary between Barind and floodplain the rivers form asymmetric valley with steeping bank along the tract sides. The width/ depth (W/D) ratios of these rivers are much lower within or near to the Tract than the nearby floodplain. The rivers fl owing from the Himalayas change their morphology, trend, nature etc. near and within the Tract. Some of the N-S fl owing rivers turned towards southeast and southwest directions to maintain slope of the uplifted Tract. These are the indication of structural control of these rivers as well as the tectonic origin of the Barind Tract rather than only geomorphic origin. Earthquakes in this region in the recent past also support the same view about structural control and neotectonic activities.

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27

ȚUȚUIANU, Laurențiu, Alfred VESPREMEANU–STROE, Florin PENDEA e Tiberiu SAVA. "Mid and Late Holocene evolution of Brateș Lake region (Danube floodplain) based on the multiproxy analysis". Revista de Geomorfologie 20, n. 1 (28 dicembre 2018): 43–55. http://dx.doi.org/10.21094/rg.2018.017.

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This study proposes a local paleo–landscape reconstruction of the Danube floodplain based on a stratigraphic sequence retrieved from Brateș Lake which, by its emplacement near the confluence of Danube – Prut rivers, was fully receptive to changes associated to hydrological, geomorphological or anthropogenic driven events. Due to its intermediate position within the Lower Danube valley Brateș Lake is a proxy for the evolution of Cotul Dunării area (the region of Danube valley turning from S–N to W–E direction) and provide valuable information about the timing of Danube river advancement to the Black Sea after its reconnection to World Ocean. The sediments were analysed to get the history of their deposition by means of accelerator mass spectrometry (AMS) 14C dating, grain–size parameters, organic matter and carbonate content, magnetic susceptibility together with paleo–fauna and pollen content which altogether led to the identification of main stages: i) delta front advance into Danube estuary (before 8000 BP), ii) shoreline foreshore deposits which describe shoreline position (8000–7900 yrs BP), iii) river floodplain development (7900–5300/5000 yrs BP), iv) lake formation (5300/5000 yrs BP – present).

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28

Daher, Victor Bastos, Rosa Cristhyna de Oliveira Vieira Paes, Gutemberg Borges França, João Bosco Rodrigues Alvarenga e Gregório Luiz Galvão Teixeira. "Extraction of Tide Constituents by Harmonic Analysis Using Altimetry Satellite Data in the Brazilian Coast". Journal of Atmospheric and Oceanic Technology 32, n. 3 (marzo 2015): 614–26. http://dx.doi.org/10.1175/jtech-d-14-00091.1.

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AbstractThis paper analyzes the sea surface height dataset from the TOPEX, Jason-1, and Jason-2 satellites of a 19-yr time series in order to extract the tide harmonic constituents for the region limited by latitude 5°N–35°S and longitude 55°–20°W. The harmonic analysis results implemented here were compared with the tidal constituents estimated by three classical tidal models [i.e., TOPEX/Poseidon Global Inverse Solution 7.2 (TPXO7.2), Global Ocean Tide 4.7 (GOT4.7), and Finite Element Solution 2102 (FES2102)] and also with those extracted from in situ measurements. The Courtier criterion was used to define the tide regimes and regionally they are classified as semidiurnal between the latitude range from approximately 5°N to 22°S, semidiurnal with diurnal inequality from 22° to about 29°S, and mixed southward of latitude 22°S. The comparison results among all tide approaches were done by analyzing the root-sum-square misfit (RSSmisfit) value. Generally, the RSSmisfit difference values are not higher than 12 cm among them in deep-water regions. On the other hand, in shallow water, all models have presented quite similar performance, and the RSSmisfit values have presented higher variance than the previous region, as expected. The major discrepancy results were particularly noted for two tide gauges located in the latitude range from 5°N to 2°S. The latter was investigated and conclusions have mainly pointed to the influence of the mouth of the Amazon River and the considerable distance between tide measurements and the satellite reference point, which make it quite hard to compare those results. In summary, the results have showed that all models presently generate quite reliable results for deep water; however, further study should done in order to improve them in shallow-water regions too.

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29

Yévenes, M., R. Figueroa, O. Parra e L. Farías. "Inter-annual variability of dissolved inorganic nitrogen in the Biobío River, Central Chile: an analysis base on a decadal database along with 1-D reactive transport modeling". Hydrology and Earth System Sciences Discussions 12, n. 1 (16 gennaio 2015): 705–38. http://dx.doi.org/10.5194/hessd-12-705-2015.

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Abstract. Rivers may act as important sinks (filters) or sources for inorganic nutrients between the land and the sea, depending on the biogeochemical processes and nutrient inputs along the river. This study examines the inter-annual variability of dissolved inorganic nitrogen (DIN) seasonal (wet–dry) cycle for the Biobío River, one of the largest and most industrialized rivers of Central Chile (36°45'–38°49' S and 71°00'–73°20' W). Long-term water flow (1990–2012) and water quality datasets (2004–2012) were used along with a one-dimensional reactive transport ecosystem model to evaluate the effects of water flow and N inputs on seasonal pattern of DIN. From 2004 to 2012, annual average nitrate levels significantly increased from 1.73 ± 2.17 μmol L−1 (upstream of the river) to 18.4 ± 12.7 μmol L−1 (in the river mouth); while the annual average oxygen concentration decreased from 348 ± 22 to 278 ± 42 μmol L−1 between upstream and downstream, indicating an additional oxygen consumption. Variability in the mid-section of the river (station BB8) was identified as a major influence on the inter-annual variability and appeared to be the site of a major anthropogenic disturbance. However, there was also an influence of climate on riverine DIN concentrations; high DIN production occurred during wet years, whereas high consumption proceeded during dry years. Extremely reduced river flow and drought during summer also strongly affected the annual DIN concentration, reducing the DIN production. Additionally, summer storm events during drought periods appeared to cause significant runoff resulting in nitrate inputs to the river. The total DIN input reaching the river mouth was 0.159 Gmol yr−1, implying that internal production exceeds consumption processes, and identifying nitrification as one of the predominant processes occurring in the estuary. In the following, the impact on the river of DIN increases as a nutrient source, as well as climate and biogeochemical factors are discussed.

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30

Hetland, Robert D. "Suppression of Baroclinic Instabilities in Buoyancy-Driven Flow over Sloping Bathymetry". Journal of Physical Oceanography 47, n. 1 (gennaio 2017): 49–68. http://dx.doi.org/10.1175/jpo-d-15-0240.1.

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AbstractBaroclinic instabilities are ubiquitous in many types of geostrophic flow; however, they are seldom observed in river plumes despite strong lateral density gradients within the plume front. Supported by results from a realistic numerical simulation of the Mississippi–Atchafalaya River plume, idealized numerical simulations of buoyancy-driven flow are used to investigate baroclinic instabilities in buoyancy-driven flow over a sloping bottom. The parameter space is defined by the slope Burger number S = Nf−1α, where N is the buoyancy frequency, f is the Coriolis parameter, and α is the bottom slope, and the Richardson number Ri = N2f2M−4, where M2 = |∇Hb| is the magnitude of the lateral buoyancy gradients. Instabilities only form in a subset of the simulations, with the criterion that SH ≡ SRi−1/2 = Uf−1W−1 = M2f−2α 0.2, where U is a horizontal velocity scale and SH is a new parameter named the horizontal slope Burger number. Suppression of instability formation for certain flow conditions contrasts linear stability theory, which predicts that all flow configurations will be subject to instabilities. The instability growth rate estimated in the nonlinear 3D model is proportional to ωImaxS−1/2, where ωImax is the dimensional growth rate predicted by linear instability theory, indicating that bottom slope inhibits instability growth beyond that predicted by linear theory. The constraint SH 0.2 implies a relationship between the inertial radius Li = Uf−1 and the plume width W. Instabilities may not form when 5Li > W; that is, the plume is too narrow for the eddies to fit.

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31

PERKINS, PHILIP D. "New species and new collection records of Prosthetopine water beetles from southern Africa (Coleoptera: Hydraenidae)". Zootaxa 1864, n. 1 (3 settembre 2008): 1. http://dx.doi.org/10.11646/zootaxa.1864.1.1.

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New species of Hydraenidae are described in the genera Prosthetops Waterhouse (1), Pterosthetops Perkins (1), Parasthetops Perkins & Balfour-Browne (13), and Mesoceration Janssens (24). New collecting locality data are given for the following species described by Perkins & Balfour-Browne (1994): Parasthetops aeneus, P. nigritus, P. spinipes, P. curidius, Mesoceration distinctum, M. rivulare, M. jucundum, M. splendorum, M. rubidum, M. fusciceps, M. languidum, M. dissonum, M. rufescens, and M. brevigranum. High resolution digital images of the holotypes of new species are presented (online version in color), and male genitalia are illustrated. Distribution maps are provided for all prosthetopine species in the genera Prosthetops, Pterosthetops, Parasthetops, and Mesoceration. The following 39 new species are described (type locality in South Africa unless otherwise given): Prosthetops gladiator (Eastern Cape Province, summit of Prentjiesberg); Pterosthetops hawequas (Western Cape Province, Hawaquas radio tower); Parasthetops benefossus(Western Cape Province, Wiedouw farm), P. buunicornus (Lesotho: Drakensberg, Sani Pass Valley), P. confluentus (Eastern Cape Province, Little Karroo, Baviaanskloof N valley), P. lemniscus (Lesotho: Drakensberg, Sani Pass Valley), P. namibiensis (Namibia: Windhoek, Eros Mt.), P. pampinus (Western Cape Province, Dorps River into Prins Albert, Swartbergpas), P. parallelus (Northern Cape Province, Richtersveld, Oemsberg), P. propitius (Lesotho: Drakensberg, Sani Pass Valley), P. retinaculus (Eastern Cape Province, Sundays River system, Letskraal), P. sebastiani (Lesotho: Drakensberg, Sani Pass Valley), P. semiplanus (Eastern Cape Province, Sundays River system, Letskraal), P. striatus (Northern Cape Province, Namaqualand, Kamieskroon), P. unicornus (Eastern Cape Province, Naudes Nek, 12 miles ENE Rhodes); Mesoceration barriotum (Western Cape Province, Cape-Swartberg, Seweweekspoort Kloof), M. bicurvum (Eastern Cape Province, Wildebees River), M. bispinum (KwaZulu-Natal Province, Weza, Impetyene Forest), M. compressum (Eastern Cape Province, S. coast, Dwesa forest reserve), M. concavum (Mpumalanga Province, Blyderiver Canyon), M. curvosum (KwaZulu-Natal Province, Umtamvuna River), M. disjunctum (Eastern Cape Province, Nature's Valley Reserve), M. drakensbergensis (Lesotho, Drakensberg, Sani Pass Valley), M. durabilis (Western Cape Province, 2 miles SW of Citrusdal), M. granulovestum (Western Cape Province, Cederberg, Eikenboom), M. incarinum (Lesotho, Drakensberg, Sani Pass Valley), M. integer (KwaZulu-Natal Province, Busheladi Stream on Lundy's Hill near Deepdale), M. littlekarroo (Western Cape Province, Little Karroo, Rus-en-vredewaterf), M. longipennis (Western Cape Province, W. Wiedouw farm), M. maluti (Lesotho, Drakensberg, Sani Pass Valley), M. natalensis (KwaZulu-Natal Province, Umkomaas River, where crossed by Himeville to Impendhle road), M. periscopum (Western Cape Province, Cederberg, Eikenboom), M. piceum (Western Cape Province, Cederberg, Eikenboom), M. rapidensis (Western Cape Province, S. W. Cape Mts., Hawequas SE), M. repandum (Western Cape Province, Cederberg, Eikenboom), M. reticulatum (Western Cape Province, Nuweberg Forest Station), M. semicarinulum (Western Cape Province, Groot Toren farm), M. tabulare (Western Cape Province, Platteklip Gorge, north face of Table Mountain), M. umbrosum (Western Cape Province, Wiedouw farm).

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Aprile, Fabio, e Assad José Darwich. "Nutrients and water-forest interactions in an Amazon floodplain lake: an ecological approach". Acta Limnologica Brasiliensia 25, n. 2 (giugno 2013): 169–82. http://dx.doi.org/10.1590/s2179-975x2013000200008.

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AIM: Catalão Lake was surveyed between 2002 and 2011 with the aim of studying seasonality of the flow of nutrients between water, sediment and aquatic macrophytes. The role of the flood pulse and the ecological mechanisms influencing the forest-water interactions in the Amazon floodplain were discussed; METHODS: Catalão Lake is located in the Amazon floodplain (03º 08'-03º 14' S and 59º 53'-59º 58' W), near the confluence of the Solimões and Negro rivers, approximately 3000 m from the port of CEASA, near the city of Manaus. It is considered to be a mixed water lake because it receives white waters rich in sediments from the Solimões River and black waters with humic substances from the Negro River. Physical and chemical parameters including C, N and P levels were studied in the diverse compartments, and a flux model was developed; RESULTS: There is a strong nutritional (C, N and P) and ionic (Na+, K+, Ca2+, Mg2+, Cl-, HCO3-, CO3(2-) and SO4(2-)) flow from the rivers to the lake. The highest C:N:P ratio was found in Paspalum repens which, during periods of drought, played an important role in releaseing nutrients into the water. The connectivity of the lake with the rivers ensured a high variation of transparency and nutrient content, fundamental for biological processes. A model of the nutrient flow, interaction and connectivity between ecosystems, and the influence of the hydrological cycle has been developed.

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33

Luz, JR, e G. Boehs. "Reproductive cycle of Anomalocardia brasiliana (Mollusca: Bivalvia: Veneridae) in the estuary of the Cachoeira River, Ilhéus, Bahia". Brazilian Journal of Biology 71, n. 3 (agosto 2011): 679–86. http://dx.doi.org/10.1590/s1519-69842011000400012.

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Abstract (sommario):

The aim of this study was to characterize the reproductive cycle of Anomalocardia brasiliana, typical of the estuarine region of the Cachoeira River, Ilhéus, Bahia, Brazil. For this purpose, 20 specimens were collected biweekly between August 2005 and August 2006 on an intertidal bank (14º 48' 23" S and 39º 02' 47" W). The animals were measured on the anteroposterior axis (length), examined macroscopically and removed from the shell and fixed in Davidson's solution. Subsequently, the tissues were impregnated in paraffin, cut into 7 mm sections and stained with Harris hematoxylin and eosin (HE). The slides were examined under a light microscope. The water temperature at the site ranged from 24 to 30.5 ºC (mean: 27.4 ºC; SD ± 1.9), salinity from zero to 23 (mean: 13.7; SD ± 7.5) and rainfall from 28.3 mm to 248.8 mm monthly (yearly mean: 130 mm). The sample (n = 478) showed a sex ratio (M: F) of 1: 1.2 (p < 0.05) and no cases of hermaphroditism. There was no sexual dimorphism. Males and females showed reproductive synchrony. The reproductive cycle was continuous, with releases of gametes mainly in spring, summer and autumn. These results are similar to those found in other regions, but there was no reproductive rest period as reported for populations in higher latitudes.

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PERKINS, PHILIP D. "New species (130) of the hyperdiverse aquatic beetle genus Hydraena Kugelann from Papua New Guinea, and a preliminary analysis of areas of endemism (Coleoptera: Hydraenidae)". Zootaxa 2944, n. 1 (8 giugno 2011): 1. http://dx.doi.org/10.11646/zootaxa.2944.1.1.

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Abstract (sommario):

The Papua New Guinea (PNG) species of the water beetle genus Hydraena Kugelann, 1794, are revised, based on the study of 7,411 databased specimens. The two previously named species are redescribed, and 130 new species are described. The species are placed in 32 species groups. High resolution digital images of all primary types are presented (online version in color), scanning electron micrographs of representative species are given, and geographic distributions are mapped. Male genitalia, representative female terminal abdominal segments and representative spermathecae are illustrated. Papua New Guinea Hydraena species are typically found in sandy/gravelly stream margins, often in association with streamside litter; some species are primarily pond or swamp dwelling, and a few species are usually found in the hygropetric splash zone on stream boulders or on rocks at the margins of waterfalls. The geographic distributions of PNG Hydraena are compared with the Areas of Freshwater Endemism recently proposed by Polhemus and Allen (2007), and found to substantially support those areas. Only one species, H. impercepta Zwick, 1977 is known to be found in both Australia and Papua New Guinea. The probable Australian origins of the PNG hydraenid genera Gymnochthebius and Limnebius are discussed. The origins of just a few species of PNG Hydraena appear to clearly be Australia, and of comparatively recent origin, whereas the origins of the remainder remain problematic because of lack of knowledge of the Hydraena fauna in Papua Province, Indonesia, and islands large and small to the west of New Guinea. No endemic genera of Hydraenidae are currently known for New Guinea, whereas 98% of the known species are endemic. New species of Hydraena are: H. acumena (Eastern Highlands Province: Koma River, tributary of Fio River), H. adelbertensis (Madang Province: Adelbert Mts., below Keki), H. akameku (Madang Province: Akameku–Brahmin, Bismarck Range), H. altapapua (Southern Highlands Province: Sopulkul, 30–35 km NE Mendi), H. ambra (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. ambripes (Madang Province: Finisterre Mts., Naho River Valley, Budemu), H. ambroides (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. apertista (Madang Province: Finisterre Mts., Lower Naho Valley, Hinggia), H. apexa (Eastern Highlands Province: Okapa), H. aquila (Madang Province: Simbai area), H. aulaarta (Western Highlands Province: Kundum), H. austrobesa (Central Province: nr. Port Moresby, Sogeri Plateau, Musgrave River), H. bacchusi (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. balkei (Eastern Highlands Province: Akameku–Brahmin, Bismarck Range), H. bicarinova (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. bifunda (Morobe Province: c. 7 mi. Lae–Bulolo road), H. biundulata (Morobe Province: Lae–Bulolo road), H. brahman (Madang Province: Ramu Valley, 4.5 km N Brahman), H. bubulla (Madang Province: Akameku–Brahmin, Bismarck Range), H. buloba (Morobe Province: Herzog Mts., Wagau), H. buquintana (Western Highlands Province: Mt. Hagen town area), H. carinocisiva (Eastern Highlands Province: Aiyura), H. carmellita (Morobe Province: Herzog Mts., Wagau), H. cavifrons (Madang Province: Ramu Valley, 4.5 km N Brahman), H. cheesmanae (Central Province: Kokoda), H. clarinis (Madang Province: Sepik Ramu Basin, Kojé Creek), H. colorata (Morobe Province: 5 miles W of Lae, Buins Creek), H. confluenta (Eastern Highlands Province: Umg. [=environs of] Kainantu, Onerunka), H. copulata (Gulf Province: Marawaka, Mala), H. cunicula (Madang Province: Akameku–Brahmin, Bismarck Range), H. decepta (Eastern Highlands Province: Okapa), H. diadema (Eastern Highlands Province: Purosa Valley, nr. Okapa), H. dudgeoni (Madang Province: Sepik Ramu Basin, Kojé Creek), H. einsteini (Central Province: Port Moresby–Brown River road), H. essentia (Eastern Highlands Province: Sepik River Basin, stream beside milestone labelled G-99), H. exhalista (Gulf Province: Marawaka, Mala), H. fasciata (Morobe Province: Herzog Mts., Wagau), H. fascinata (Madang Province: Finisterre Mts., Naho River Valley, nr. Moro), H. fasciolata (Madang Province: Madang, Ohu Village), H. fasciopaca (Madang Province: Keki, Adelbert Mts.), H. fenestella (Morobe Province: Lae-Bulolo road), H. foliobba (Morobe Province: Herzog Mts., Wagau), H. formosopala (East Sepik Province: Prince Alexander Mts., Wewak), H. funda (Central Province: Moitaka, 7 miles N of Port Moresby), H. fundacta (Madang Province: Adelbert Mts., Sewan–Keki), H. fundapta (Central Province: Port Moresby–Brown River road), H. fundarca (Eastern Highlands Province: Okapa), H. fundextra (Morobe Province: Markham Valley, Gusap), H. galea (Eastern Highlands Province: Akameku–Brahmin, Bismarck Range, 700 m), H. herzogestella (Morobe Province: Herzog Mts., Bundun), H. hornabrooki (East Sepik Province: Sepik, main river), H. huonica (Madang Province: Kewensa, Finisterre Range, Yupna, Huon Peninsula), H. ibalimi (Sandaun Province: Mianmin), H. idema (Eastern Highlands Province: Umg. [=environs of] Onerunka, Ramu River), H. impala (Central Province: nr. Port Moresby, Sogeri Plateau, Musgrave River), H. incisiva (Morobe Province: Herzog Mts., Wagau), H. incista (Western Highlands Province: Simbai, Kairong River), H. infoveola (Gulf Province: Marawaka, Mala), H. inhalista (Madang Province: Finisterre Mts., Naho River Valley, Damanti), H. inplacopaca (Eastern Highlands Province: Waisa, nr. Okapa), H. insandalia (Eastern Highlands Province: Headwaters of Fio River, 0.5 km downstream of river crossing on Herowana/Oke Lookout path, ca. 4.5 km N of Herowana airstrip), H. intensa (Morobe Province: Lae–Bulolo road), H. johncoltranei (National Capital District, Varirata NP), H. jubilata (Madang Province: Finisterre Mts., Naho River Valley, Budemu), H. koje (Madang Province: Sepik Ramu Basin, Kojé Creek), H. koma (Eastern Highlands Province: Koma River, tributary of Fio River, 100 m downstream of rattan bridge crossing, ca. 3.8 km S by E of Herowana airstrip), H. labropaca (Central Province: nr. Port Moresby, Sogeri Plateau, Musgrave River), H. lassulipes (Morobe Province: Herzog Mts., Wagau), H. limbobesa (Gulf Province: Marawaka, near Ande), H. maculopala (Madang Province: Madang, Ohu Village), H. manulea (Morobe Province: Lae, Buins Creek), H. manuloides (Central Province: Port Moresby–Brown River road), H. marawaka (Gulf Province: Marawaka, Mala), H. mercuriala (Sandaun Province: May River), H. mianminica (Sandaun Province:May River), H. nanocolorata (Madang Province: Sepik Ramu Basin, Kojé Creek), H. nanopala (Madang Province: Sepik Ramu Basin, Kojé Creek), H. nitidimenta (Eastern Highlands Province: Koma River, tributary of Fio River, at rattan bridge crossing, ca. 2.6 km N by W of Herowana airstrip), H. okapa (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. ollopa (Western Highlands Province: Kundum), H. otiarca (Morobe Province: Herzog Mts., Wagau, Snake River), H. owenobesa (Morobe Province: ca. 10 km S Garaina Saureri), H. pacificica (Morobe Province: Huon Pen., Kwapsanek), H. pala (Morobe Province: Lae–Bulolo road, Gurakor Creek), H. palamita (Central Province: nr. Port Moresby, Sogeri Plateau, Musgrave River), H. paxillipes (Morobe Province: Lae–Bulolo road, Patep Creek), H. pectenata (Madang Province: Finisterre Mts., Naho River Valley, Damanti), H. pegopyga (Madang Province: Ramu Valley, 3 km N Brahman), H. penultimata (Sandaun Province: May River), H. perpunctata (Madang Province: Sepik Ramu Basin, Kojé Creek), H. pertransversa (Eastern Highlands Province: Clear stream, summit of Kassem Pass at forest level), H. phainops (Morobe Province: Lae–Bulolo road, Patep Creek), H. photogenica (Eastern Highlands Province: Goroka, Mt. Gahavisuka), H. picula (Eastern Highlands Province: Goroka, Daulo Pass), H. pilulambra (Eastern Highlands Province: Clear stream, summit of Kassem Pass at forest level), H. pluralticola (Morobe Province: c. 7 miles Lae–Bulolo road), H. processa (Morobe Province: Herzog Mts., Wagau), H. quadriplumipes (Madang Province: Aiome area), H. quintana (Morobe Province: Markham Valley, Lae–Kainantu road, Erap R), H. ramuensis (Madang Province: Ramu Valley, 6 km N Brahman), H. ramuquintana (Madang Province: Ramu Valley, 6 km N Brahman), H. receptiva (Morobe Province: Lae–Bulolo road), H. remulipes (Morobe Province: Herzog Mts., Wagau), H. reticulobesa (Madang Province: Finisterre Mts., Naho River Valley, Moro), H. sagatai (Sandaun Province: Abau River), H. saluta (Madang Province: Finisterre Mts., Naho River Valley, Damanti), H. sepikramuensis (Madang Province: Ramu Valley, Sare River, 4 km N Brahman), H. sexarcuata (Eastern Highlands Province: Akameku–Brahmin, Bismarck Range), H. sexsuprema (Madang Province: Finisterre Mts., Naho River Valley, Damanti), H. spinobesa (Madang Province: Finisterre Mts., Naho River Valley, Budemu), H. striolata (Oro Province: Northern District, Tanbugal Afore village), H. supersexa (Eastern Highlands Province: Okapa), H. supina (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. tarsotricha (Morobe Province: Herzog Mts., Wagau, Snake River), H. tetana (Eastern Highlands Province: Okapa), H. thola (Central Province: Port Moresby– Brown River road), H. tholasoris (Morobe Province: Markham Valley, Gusap, c. 90 miles NW of Lae), H. thumbelina (Madang Province: Finisterre Mts., Naho River Valley, Damanti), H. thumbelipes (Sandaun Province: Mianmin), H. tibiopaca (Morobe Province: ridge between Aseki–Menyamya), H. torosopala (Madang Province: Keki, Adelbert Mts.), H. torricellica (Morobe Province: Torricelli Mts., village below Sibilanga Stn.), H. transvallis (Madang Province: Finisterre Mts., Naho River Valley, Damanti), H. trichotarsa (Morobe Province: Lae–Bulolo road), H. tricosipes (Morobe Province: Herzog Mts., Wagau), H. tritropis (Madang Province: Sepik Ramu Basin, Kojé Creek), H. tritutela (Morobe Province: ca. 10 km S Garaina Saureri), H. ulna (Morobe Province: Herzog Mts., Wagau), H. variopaca (Eastern Highlands Province: Wanitabi Valley, nr. Okapa), H. velvetina (Eastern Highlands Province: Purosa Valley, nr. Okapa).

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35

Sarıgül, Tuba, Recai İnam, Ersin Demir e Hassan Y. Aboul-Enein. "Electro-Oxidation and Determination of Benomyl by Square-Wave Adsorptive Stripping Voltammetry". Journal of AOAC INTERNATIONAL 97, n. 4 (1 luglio 2014): 995–1000. http://dx.doi.org/10.5740/jaoacint.sgesarigul.

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Abstract The electro-oxidation of the benomyl fungicide was studied by square-wave adsorptive stripping voltammetry. The voltammetric current at a glassy carbon electrode was acquired within the pH range 1.0–10.0. The quantitation was performed using the peak generated at +1144 mV by scanning the potential from +0.00 to +1600 mV (versus an Ag/AgCl reference electrode, 3 M NaCl). Accumulation potential = 0.0 mV, accumulation time = 45 s, frequency = 75 Hz, pulse amplitude = –60 mV, and staircase step potential = 7 mV were used as square-wave parameters. The peak current versus concentrations plot were rectilinear over the range from 0.081 to 1.496 μg/mL with an LOD of 0.024 μg/mL. Mean recovery was 99.0% (0.198 ± 0.011 μg/mL), which was very close to the benomyl content spiked into river water (0.20 μg/mL). The method was efficiently applied for benomyl determination in the pesticide formulation Minelate 50WG®, and the average determined content of 49.8 ± 0.16 (n = 5) was consistent with the 50% benomyl (w/w) quoted by the manufacturer. The benomyl voltammograms recorded between days exhibited a negligible degradation into carbendazim metabolite, and therefore all results were given as the total benomyl concentration. The high recoveries and low RSD gave evidence of good accuracy and precision.

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36

Χατούπης, Θ., e I. Φουντούλης. "NEOTECTONIC DEFORMATION OF NORTH PARNIS". Bulletin of the Geological Society of Greece 36, n. 4 (1 gennaio 2004): 1588. http://dx.doi.org/10.12681/bgsg.16560.

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The morphotectonic analysis in the eastern part of Biotic Asopos river catchment, results to an explicit picture of a new drainage network with individual abnormalities that are focused mainly in phenomena of "piracy" and abrupt knick points. Topographic sections along the main streams and correlation between rose diagrams of faults and stream network reveal an influence of the drainage network (E-W and N-S direction) from the active tectonic structure of E-W to WNW-ESE direction, which is accompanied by phenomena of intense depth erosion transversely to the main active tectonic faults. The important dextral slip component of the main active fault zones (Sfendali-Avlona and Milesi Oropos) has influenced the alpine tectonic structure, determining the current NE-SW spread of Upper Cretaceous limestones and changing the direction of flysch axes from NNE-SSW in mountainous Parnis area to ENE-WSW in the flat area of Malakasa. The distribution of planation surfaces in combination with the presence of en echelon oblique slip faults of WNW-ESE direction, reveal a complex kinematic evolution, with main characteristics the progressive rotation of tectonic blocks to the WNW for the mountainous south area and to the SSW for the NE area of low relief.

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37

Jury, Mark R. "Weather–Climate Interactions in the Eastern Antilles and the 2013 Christmas Storm". Earth Interactions 18, n. 19 (1 novembre 2014): 1–20. http://dx.doi.org/10.1175/ei-d-14-0011.1.

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Abstract This study considers eastern Antilles (11°–18°N, 64°–57°W) weather and climate interactions in the context of the 2013 Christmas storm. This unseasonal event caused flash flooding in Grenada, St. Vincent, St. Lucia, Martinique, and Dominica from 24 to 25 December 2013, despite having winds <15 m s−1. The meteorological scenario and short-term forecasts are analyzed. At the low level, a convective wave propagated westward while near-equatorial upper westerly winds surged with eastward passage of a trough. The combination of tropical moisture, cyclonic vorticity, and uplift resulted in rain rates greater than 30 mm h−1 and many stations reporting 200 mm. Although forecast rainfall was low and a few hours late, weather services posted flood warnings in advance. At the climate scale, the fresh Orinoco River plume brought into the region by the North Brazil Current together with solar radiation greater than 200 W m−2, enabled sea temperatures to reach 28°C, and supplied convective available potential energy greater than 1800 J kg−1. Climate change model simulations are compared with reference fields and trends are analyzed in the eastern Antilles. While temperatures are set to increase, the frequency of flood events appears to decline in the future.

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38

Miller, Dean, Matthew Liu e William Abraham Tarpeh. "Evaluating Molecular Catalyst-Mediated Nitrate Reduction for Reactive Separation and Recovery of Ammonia". ECS Meeting Abstracts MA2022-01, n. 40 (7 luglio 2022): 1799. http://dx.doi.org/10.1149/ma2022-01401799mtgabs.

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The current state of centralized nitrogen (N) management has destabilized global environmental cycles via Haber-Bosch (HB) ammonia-N manufacturing which contributes 1.2% of global anthropogenic CO2-eq emissions.1 The majority of this N that is discharged to wastewaters goes untreated, leading to harmful algal blooms that threaten coastal and river ecosystems, which already costs the U.S. an estimated $210 billion per year in health and environmental damages.2 Furthermore, the production of HB ammonia, and the subsequent discharge of wastewater nitrogen, is expected to substantially increase in the next three decades as the human population climbs to 9 billion people.3 Simultaneously removing nitrogen pollutants and recovering value-added products can preserve national water quality and supplement supply chains of nitrogen consumables with renewably sourced electricity. The electrochemical nitrate reduction reaction (NO3RR) can be leveraged in reactive separation processes to convert wastewater nitrates to commodity products, such as ammonia. Engineering catalytic NO3RR processes that operate at feasible rates and faradaic efficiencies is challenging because the majority of nitrate-rich wastewaters (e.g., fertilizer runoff) are dilute in nitrate concentration (< 5 mM).4 Molecular catalysts are uniquely suited to reduce nitrate at low concentrations in real wastewaters due to their strong substrate recognition (reactant selectivity) and product selectivity. In this study, we benchmarked the performance of the molecular catalyst Co-DIM (a Co-N4 macrocycle complex and the only known molecular NO3RR catalyst selective for ammonia5) in a reactive separations process for the treatment of real, nitrate-rich wastewaters. We first demonstrated by cyclic voltammetry (CV) and controlled-potential electrolysis (CPE) that selective Co-DIM-mediated NO3RR is feasible in nitrate-rich secondary effluent (municipal wastewater after biological nitrification). We then employed Co-DIM in electrochemical stripping (ECS): a membrane-separated cell that facilitates reactive separation of produced ammonia.6,7 From real secondary effluent (28 mg NO3-N/L), we achieved greater than 60% nitrate removal with a faradaic efficiency of 25% and ammonia selectivity of 98%. However, the energy consumed for ECS per unit mass of N is 16 times the combined energy requirement for conventional wastewater N removal and HB ammonia synthesis. By introducing a mixed feed of ammonia- and nitrate-rich wastewater and performing electrodialysis (ED) to concentrate the reactant nitrate before ECS, the energy requirement for N removal and ammonia recovery was decreased by three times while the ED process became the dominant energy consumer in the overall process. Additionally, the increase in nitrate removal could not be explained by an increase in nitrate concentration alone. The ED process changes the concentrations and relative ratios of competing anions and buffering species, which can inhibit or promote the molecular electrocatalytic activity. We therefore explored a matrix of anion identities and concentrations by rotating-disk voltammetry and CPE to elucidate plausible inhibition and promotion mechanisms associated with catalyst activation and NO3RR catalysis. This study therefore (1) benchmarks current and future efforts to reactively separate ammonia from real nitrate-rich wastewater with a molecular catalyst and (2) highlights molecular and process-level improvements to realize a circular nitrogen economy. References 1 C. Smith, A. K. Hill and L. Torrente-Murciano, Energy Environ. Sci., 2020, 13, 331–344. 2 D. J. Sobota, J. E. Compton, M. L. McCrackin and S. Singh, Environ. Res. Lett., 2015, 10, 025006. 3 J. W. Erisman, M. A. Sutton, J. Galloway, Z. Klimont and W. Winiwarter, Nature Geoscience, 2008, 1, 636–639. 4 Unesco, Ed., Wastewater: the untapped resource, UNESCO, Paris, 2017. 5 S. Xu, D. C. Ashley, H.-Y. Kwon, G. R. Ware, C.-H. Chen, Y. Losovyj, X. Gao, E. Jakubikova and J. M. Smith, Chem. Sci., 2018, 9, 4950–4958. 6 W. A. Tarpeh, J. M. Barazesh, T. Y. Cath and K. L. Nelson, Environ. Sci. Technol., 2018, 52, 1453–1460. 7 M. J. Liu, B. S. Neo and W. A. Tarpeh, Water Research, 2020, 169, 115226.

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39

Gupta, V. K., e O. J. Mesa. "Horton laws for Hydraulic-Geometric variables and their scaling exponents in self-similar river networks". Nonlinear Processes in Geophysics Discussions 1, n. 1 (16 aprile 2014): 705–53. http://dx.doi.org/10.5194/npgd-1-705-2014.

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Abstract. An analytical theory is presented to predict Horton laws for five Hydraulic-Geometric (H-G) variables (stream discharge Q, width W, depth D, velocity U, slope S, and friction n'). The theory builds on the concept of dimensional analysis, and identifies six independent dimensionless River-Basin numbers. We consider self-similar Tokunaga networks and derive a mass conservation equation in the limit of large network order in terms of Horton bifurcation and discharge ratios. It is applied to obtain self-similar solutions of type-1 (SS-1), and predict Horton laws for width, depth and velocity as asymptotic relationships. Exponents of width and the Reynold's number are predicted. Assuming that SS-1 is valid for slope, depth and velocity, corresponding Horton laws and the H-G exponents are derived. The exponent values agree with that for the Optimal Channel Network (OCN) model, but do not agree with values from three field experiments. The deviations are substantial, suggesting that H-G in network does not obey optimality or SS-1. It fails because slope, a dimensionless River-Basin number, goes to 0 as network order increases, but, it cannot be eliminated from the asymptotic limit. Therefore, a generalization of SS-1, based in self-similar solutions of Type-2 (SS-2) is considered. It introduces two anomalous scaling exponents as free parameters, which enables us to show the existence of Horton laws for channel depth, velocity, slope and Manning's friction. The Manning's friction exponent, y, is predicted and tested against observed exponents from three field studies. We briefly sketch how the two anomalous scaling exponents could be estimated from the transport of suspended sediment load and the bed load. Statistical variability in the Horton laws for the H-G variables is also discussed. Both are important open problems for future research.

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40

Ouattara, Souleymane Gningnéri, Brou Dibi e Jules Mangoua Oi Mangoua. "Contribution of RADARSAT-1 Images to Structural Geological Mapping and Lineament Density Assessment in the Lobo River Watershed at Nibéhibé (Centre-West, Côte d'Ivoire)". European Journal of Environment and Earth Sciences 2, n. 4 (10 luglio 2021): 15–20. http://dx.doi.org/10.24018/ejgeo.2021.2.4.147.

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The populations living in the Lobo watershed at Nibéhibé are experiencing difficulties in obtaining drinking water. This situation is due to several factors, including a lack of control of the hydrogeological environment. The present study assesses the fracture network that has affected the Precambrian basement aquifer of the Lobo at Nibéhibé catchment area by structural mapping and by studying the spatial distribution of the lineaments. To do this, the study exploits the contribution of radar images. Manually and with the use of adaptive and median filters, 1330 lineaments of varying lengths were derived from the RADARSAT-1 image. The validation approach was based on the comparison of the lineament’s orientations of the current study with those of previous studies, and on the position of the geophysically-implanted boreholes relative to the fractures. This approach showed that the lineaments would most often correspond to fractures and would be involved in the occurrence of groundwater. The analysis of the orientation distribution of the lineaments revealed the heterogeneity of the directions and the predominance of the N-S and E-W family directions. The lineament density map showed that the study area is intensely fractured with a proportion of 93%. The results obtained from this thematic map are useful for the implementation of high efficiency hydraulic drilling programmes and for the implementation of water resources management tools.

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41

Madabhushi, Sriram, e Pradeep Talwani. "Fault plane solutions and relocations of recent earthquakes in Middleton Place Summerville Seismic Zone near Charleston, South Carolina". Bulletin of the Seismological Society of America 83, n. 5 (1 ottobre 1993): 1442–66. http://dx.doi.org/10.1785/bssa0830051442.

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Abstract The Middleton Place Summerville Seismic Zone (MPSSZ), located about 20 km northwest of Charleston is the most active seismic zone in South Carolina. Between 1980 and 1991, 58 events with Md 0.8 to 3.3 were recorded in MPSSZ. They lie in a diffuse area of 11 km by 14 km of which over two-thirds are located in a narrow 5 km by 6-km zone. The hypocentral depths range from 2 to 11 km with over 90% deeper than 4 km. Single fault plane solutions were obtained for 35 events. Based on the focal mechanisms the earthquakes were grouped into five subsets. The mean P-axis of all fault plane solutions is oriented N63°E, in general agreement with the direction of SHmax obtained from in situ stress measurements. Of the 35 events, 18 are associated with reverse faulting on NW - SE striking and SW dipping fault planes. These events were inferred to be associated with the Ashley River fault zone, which is not a planar feature, but is composed of short segments of varying strikes (N20°W to N70°W) and dips (40° to 70°SW). Eleven events were associated with strike-slip motion on NNE - SSW striking vertical faults and with thrust faulting on N - S oriented faults dipping to the west, respectively. These two sets are identified as being parts of the Woodstock fault zone. The concentrated zone of seismicity included events associated with both the ARF and WF zones suggesting that it is at the intersection of these two fault zones.

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42

Zhang, X. Y., Y. Q. Wang, T. Niu, X. C. Zhang, S. L. Gong, Y. M. Zhang e J. Y. Sun. "Atmospheric aerosol compositions in China: spatial/temporal variability, chemical signature, regional haze distribution and comparisons with global aerosols". Atmospheric Chemistry and Physics Discussions 11, n. 9 (26 settembre 2011): 26571–615. http://dx.doi.org/10.5194/acpd-11-26571-2011.

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Abstract. During 2006 and 2007, the daily concentrations of major water-soluble constituents, mineral aerosol, organic carbon (OC) and elemental carbon (EC) in ambient PM10 samples were investigated from 16 urban, rural and remote sites in various regions of China, and were compared with global aerosol. A large difference between urban and rural chemical species was found, normally with 1.5 to 2.5 factors higher in urban than in rural sites. Optically-scattering aerosols such as sulfate (~16%), OC (~15%), nitrate (~7%) and ammonium (~5%) consist of ~50% of the total aerosols with another ~35% from mineral aerosol also having a certain degree of scattering ability, indicating a dominant scattering feature of aerosols in China. Of the total OC, ~55%–60% can be attributed to the secondary organic carbon (SOC). The absorbing aerosol EC accounts for ~3.5% of the total PM10. Seasonally, maximum concentrations of most aerosol species are found in winter while mineral aerosol also peaks in spring. Second peaks were found for sulfate and ammonium in summer and for OC and EC in May and June. This can be considered as a typical seasonal pattern in various aerosol components in China. Aerosol acidity is normally neutral in most of urban areas, but becomes somewhat acidic in rural areas. Based on the surface visibility from 681 meteorological stations in China during 1957–2005, four major haze areas are also identified with similar visibility changes, namely, (1) Hua Bei Plain in N. China, plus the Guanzhong Plain; (2) E. China with the main body in the Yangtze River Delta area; (3) S. China with most areas of Guangdong and the Pearl River Delta area; (4) The Si Chuan Basin in S. W. China. The degradation of visibility in these areas is linked with the emission changes and high PM concentrations. Such quantitative chemical characterization of aerosols is essential in assessing their role in atmospheric chemistry and weather-climate effects, and in validating atmospheric models.

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43

Andrews, John T., e Gita Dunhill. "Early to mid-Holocene Atlantic water influx and deglacial meltwater events, Beaufort Sea Slope, Arctic Ocean". Quaternary Research 61, n. 1 (gennaio 2004): 14–21. http://dx.doi.org/10.1016/j.yqres.2003.08.003.

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Holocene high-resolution cores from the margin of the Arctic Ocean are rare. Core P189AR-P45 collected in 405-m water depth on the Beaufort Sea slope, west of the Mackenzie River delta (70°33.03′N and 141°52.08′W), is in close vertical proximity to the present-day upper limit of modified Atlantic water. The 5.11-m core spans the interval between ∼6800 and 10,400 14C yr B.P. (with an 800-yr ocean reservoir correction). The sediment is primarily silty clay with an average grain-size of 9 φ. The chronology is constrained by seven radiocarbon dates. The rate of sediment accumulation averaged 1.35 mm/yr. Stable isotopic data (δ18O and δ13C) were obtained on the polar planktonic foraminifera Neogloboquadrina pachyderma (s) and the benthic infaunal species Cassidulina neoteretis. A distinct low-δ18O event is captured in both the benthic and planktonic data at ∼10,000 14C yr B.P.—probably recording the glacial Lake Agassiz outburst flood associated with the North Atlantic preboreal cold event. The benthic foraminifera are dominated in the earliest Holocene by C. neoteretis, a species associated with modified Atlantic water masses. This species decreases toward the core top with a marked environmental reversal occurring ∼7800 14C yr B.P. possibly coincident with the northern hemisphere 8200 cal yr B.P. cold event.

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Jackson, Lily J., Brian K. Horton e Cristian Vallejo. "Detrital zircon U-Pb geochronology of modern Andean rivers in Ecuador: Fingerprinting tectonic provinces and assessing downstream propagation of provenance signals". Geosphere 15, n. 6 (8 novembre 2019): 1943–57. http://dx.doi.org/10.1130/ges02126.1.

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Abstract Recognizing detrital contributions from sediment source regions is fundamental to provenance studies of active and ancient orogenic settings. Detrital zircon U-Pb geochronology of unconsolidated sands from modern rivers that have source catchments with contrasting bedrock signatures provides insight into the fidelity of U-Pb age signatures in discriminating tectonic provenance and downstream propagation of environmental signals. We present 1705 new detrital zircon U-Pb ages for 15 samples of unconsolidated river sands from 12 modern rivers over a large spatial extent of Ecuador (∼1°N–5°S and ∼79°–77°W). Results show distinctive U-Pb age distributions with characteristic zircon age populations for various tectonic provinces along the Andean convergent margin, including the forearc, magmatic arc, and internal (hinterland) and external (foreland) segments of the fold-thrust belt. (1) Forearc and magmatic arc (Western Cordillera) river sands are characterized by Neogene–Quaternary age populations from magmatic sources. (2) Rivers in the hinterland (Eastern Cordillera) segment of the Andean fold-thrust belt have substantial populations of Proterozoic and Paleozoic ages, representing upper Paleozoic–Mesozoic sedimentary and metasedimentary rocks of ultimate cratonic origin. (3) River sands in the frontal fold-thrust belt (Subandean Zone to Oriente Basin) show distinctive bimodal Jurassic age populations, a secondary Triassic population, and subordinate Early Cretaceous ages representative of Mesozoic plutonic and metamorphic bedrock. Detrital zircon U-Pb results from a single regional watershed (Rio Pastaza) spanning the magmatic arc to foreland basin show drastic downstream variations, including the downstream loss of magmatic arc and hinterland signatures and abrupt introduction and dominance of selected sources within the fold-thrust belt. Disproportionate contributions from Mesozoic crystalline metamorphic rocks, which form high-elevation, high-relief areas subject to focused precipitation and active tectonic deformation, are likely the product of focused erosion and high volumes of local sediment input from the frontal fold-thrust belt, leading to dilution of upstream signatures from the hinterland and magmatic arc.

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45

Zica, E. O. P., H. Brandão, C. H. Zawadzki, A. B. Nobile, E. D. Carvalho e R. J. da Silva. "The occurrence of Austrodiplostomum compactum (Lutz, 1928) (Digenea: Diplostomidae) metacercariae in the eyes of loricariid fish (Siluriformes: Osteichthyes: Loricariidae) from Brazil". Journal of Helminthology 85, n. 1 (12 maggio 2010): 73–79. http://dx.doi.org/10.1017/s0022149x10000271.

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AbstractThe aim of this study was to report the occurrence of Austrodiplostomum compactum metacercariae in the eyes of 98 specimens of loricariid fish (Hypostomus ancistroides, H. hermanni, H. iheringii, H. margaritifer, H. regani, H. strigaticeps, Hypostomus sp. and Megalancistrus parananus) from the Chavantes reservoir (23°07′36″S and 49°37′35″W) located in the rio Paranapanema, upper Paraná river basin, municipality of Ipaussu, São Paulo State, Brazil. Fish were collected from October 2007 to February 2009 using nylon monofilament gill nets and transported to the field laboratory where they were euthanized and the eyes were taken and examined under a stereomicroscope. Hypostomus ancistroides and M. parananus were not infected by this diplostomid. Hypostomus hermanni and H. margaritifer were represented by only one specimen but both had a high intensity of A. compactum metacercarie (27 and 35, respectively). Hypostomus strigaticeps (n = 45) and H. iheringii (n = 28) were the most representative specimens and the prevalence, mean intensity of infection and mean abundance were 24.4%, 10.3 and 2.7, and 64.2%, 13.1 and 8.4, respectively. No correlation was observed between the intensity of infection and the standard length (r = − 0.223; P = 0.827) and weight (r = 0.03; P = 0.779) of studied fish. Similarly, linear regression among these variables showed a poor correlation and indicated that the infection by A. compactum metacercariae occurs similarly in small and large fish specimens. A seasonal pattern of infection was not observed. Hypostomus hermanni, H. iheringii, H. margaritifer and H. strigaticeps were new hosts recorded for A. compactum metacercariae. A review of morphometric data of A. compactum metacercariae is presented.

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Phach, Phung Van, e Le Duc Anh. "Tectonic evolution of the southern part of Central Viet Nam and the adjacent area". Geodynamics & Tectonophysics 9, n. 3 (9 ottobre 2018): 801–25. http://dx.doi.org/10.5800/gt-2018-9-3-0372.

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Interpretations of seismic, gravity and magnetic anomalies and structural data on the coastal zone of southern part of Central Viet Nam (SCVN) and the adjacent Tertiary basins suggest several phases in the tectonic evolution of the study region since the Late Cretaceous to Quaternary. In this paper, we try to clarify the tectonic evolution of SCVN and the adjacent continental margin. The Cretaceous – Paleocene tectonic phase commenced after cessation of the West Pacific plutonic magmatic activity that produced numerous diabases and aplite dykes of mainly sub-meridian orientation. It was characterized by N–S compression and E–W extension. The geomorphology and geology ofSE Asiawere considerably changed during the Neotectonic phases caused by collision between the Indian plate and the Eurasian continent. Two tectonic phases – Early and Late Neotectonic – are separated by a regional unconformity represented by a boundary surface between below strongly deformed strata (synrift) and above less deformed formations (post-rift). The Early Neotectonic phase was related to the left-lateral movement of the Red River Fault Zone (RRFZ) and includes two tectonic sub-phases: Eocene – Oligocene (NW–SE compression), and Oligocene – Miocene (E–W compression). Activity in the Oligocene-Miocene sub-phase gave birth to rift basins in the continental margin of the SCVN. The Late Neotectonic phase began since the RRFZ stopped left-lateral movement and the East Viet Nam (orSouth China) Sea stopped spreading. The Late Neotectonic phase is also divided into two tectonic sub-phases: Late Early Miocene (sub-meridian compression), and Late Miocene – Pliocene (NE–SW compression). The Late Miocene – Pliocene sub-phase is characterized by vertical movements that caused episodic uplifting of the onland terrains, and subsidence of the offshore Phu Khanh basin. Besides, Miocene – Pliocene-Quarternary basaltic eruptions were widespread all over the southern Indosinian terrain and the continental margin.

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Chen, Ge, Zhimin Xu, Dmytro Rudakov, Yajun Sun e Xin Li. "Deep Groundwater Flow Patterns Induced by Mine Water Injection Activity". International Journal of Environmental Research and Public Health 19, n. 23 (22 novembre 2022): 15438. http://dx.doi.org/10.3390/ijerph192315438.

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Mine water injection into deep formations is one of the effective approaches for reducing the drainage from coal mines in the arid and semi-arid region of the Ordos basin, China. Many coal mines are attempting to execute the related projects. Under the influence of groundwater protection, the understanding of regional groundwater flow is becoming highly important to the mine water monitoring, whereas quite few academic research teams focus on the deep groundwater flow pattern by mine water injection. This paper reveals the spatial distribution of Liujiagou Formation that is in positive correlation with the terrain, and its local thickness is influenced by the dominant W-E and NE-SW directions of geological structures. Only a part of sandstone rocks consists of aquifers, the rest 61.9% of relatively dry rock provide the enhanced storage space and partial mudstone aquicludes decrease the possibility of the vertical leakage for mine water. The dynamic storage capacity is evaluated at 2.36 Mm3 per 1 km2 and over 25.10 billion m3 in this study area. Two hydrogeologic cross-sections of basin-scale identify the W-E and N-S regional groundwater flow directions, with the lower Yellow River catchment becoming the discharged region. The hierarchically and steadily nested flow systems containing coal mining claims are influenced by coal mining activity. The groundwater depression cone in a shallow coal measure aquifer is caused by mine water drainage whereas the groundwater mound in Liujiagou Formation is generated by mine water injection activity. The numerical simulation revealed that the groundwater head rebound is slightly decreased and will not recover to its initial baseline within 500 years due to its low porosity and permeability. This study elucidates the deep groundwater flow patterns induced by mine water injection and provides a practical methodology for the management and pollution monitoring of mine water injection activity.

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PERKINS, PHILIP D. "A revision of the Australian species of the water beetle genus Hydraena Kugelann (Coleoptera: Hydraenidae)". Zootaxa 1489, n. 1 (31 maggio 2007): 1–207. http://dx.doi.org/10.11646/zootaxa.1489.1.1.

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The Australian species of the water beetle genus Hydraena Kugelann, 1794, are revised, based on the study of 7,654 specimens. The 29 previously named species are redescribed, and 56 new species are described. The species are placed in 24 species groups. High resolution digital images of all primary types are presented (online version in color), and geographic distributions are mapped. Male genitalia, representative female terminal abdominal segments and representative spermathecae are illustrated. Australian Hydraena are typically found in sandy/gravelly stream margins, often in association with streamside litter; some species are primarily pond dwelling, a few species are humicolous, and one species may be subterranean. The areas of endemicity and species richness coincide quite closely with the Bassian, Torresian, and Timorian biogeographic subregions. Eleven species are shared between the Bassian and Torresian subregions, and twelve are shared between the Torresian and Timorian subregions. Only one species, H. impercepta Zwick, is known to be found in both Australia and Papua New Guinea. One Australian species, H. ambiflagellata, is also known from New Zealand. New species of Hydraena are: H. affirmata (Queensland, Palmerston National Park, Learmouth Creek), H. ambiosina (Queensland, 7 km NE of Tolga), H. antaria (New South Wales, Bruxner Flora Reserve), H. appetita (New South Wales, 14 km W Delagate), H. arcta (Western Australia, Synnot Creek), H. ascensa (Queensland, Rocky Creek, Kennedy Hwy.), H. athertonica (Queensland, Davies Creek), H. australula (Western Australia, Synnot Creek), H. bidefensa (New South Wales, Bruxner Flora Reserve), H. biimpressa (Queensland, 19.5 km ESE Mareeba), H. capacis (New South Wales, Unumgar State Forest, near Grevillia), H. capetribensis (Queensland, Cape Tribulation area), H. converga (Northern Territory, Roderick Creek, Gregory National Park), H. cubista (Western Australia, Mining Camp, Mitchell Plateau), H. cultrata (New South Wales, Bruxner Flora Reserve), H. cunninghamensis (Queensland, Main Range National Park, Cunningham's Gap, Gap Creek), H. darwini (Northern Territory, Darwin), H. deliquesca (Queensland, 5 km E Wallaman Falls), H. disparamera (Queensland, Cape Hillsborough), H. dorrigoensis (New South Wales, Dorrigo National Park, Rosewood Creek, upstream from Coachwood Falls), H. ferethula (Northern Territory, Cooper Creek, 19 km E by S of Mt. Borradaile), H. finniganensis (Queensland, Gap Creek, 5 km ESE Mt. Finnigan), H. forticollis (Western Australia, 4 km W of King Cascade), H. fundaequalis (Victoria, Simpson Creek, 12 km SW Orbost), H. fundata (Queensland, Hann Tableland, 13 km WNW Mareeba), H. hypipamee (Queensland, Mt. Hypipamee National Park, 14 km SW Malanda), H. inancala (Queensland, Girraween National Park, Bald Rock Creek at "Under-ground Creek"), H. innuda (Western Australia, Mitchell Plateau, 16 mi. N Amax Camp), H. intraangulata (Queensland, Leo Creek Mine, McIlwrath Range, E of Coen), H. invicta (New South Wales, Sydney), H. kakadu (Northern Territory, Kakadu National Park, Gubara), H. larsoni (Queensland, Windsor Tablelands), H. latisoror (Queensland, Lamington National Park, stream at head of Moran's Falls), H. luminicollis (Queensland, Lamington National Park, stream at head of Moran's Falls), H. metzeni (Queensland, 15 km NE Mareeba), H. millerorum (Victoria, Traralgon Creek, 0.2 km N 'Hogg Bridge', 5.0 km NNW Balook), H. miniretia (Queensland, Mt. Hypipamee National Park, 14 km SW Malanda), H. mitchellensis (Western Australia, 4 km SbyW Mining Camp, Mitchell Plateau), H. monteithi (Queensland, Thornton Peak, 11 km NE Daintree), H. parciplumea (Northern Territory, McArthur River, 80 km SW of Borroloola), H. porchi (Victoria, Kangaroo Creek on Springhill Rd., 5.8 km E Glenlyon), H. pugillista (Queensland, 7 km N Mt. Spurgeon), H. queenslandica (Queensland, Laceys Creek, 10 km SE El Arish), H. reticuloides (Queensland, 3 km ENE of Mt. Tozer), H. reticulositis (Western Australia, Mining Camp, Mitchell Plateau), H. revelovela (Northern Territory, Kakadu National Park, GungurulLookout), H. spinissima (Queensland, Main Range National Park, Cunningham's Gap, Gap Creek), H. storeyi (Queensland, Cow Bay, N of Daintree River), H. tenuisella (Queensland, 3 km W of Batavia Downs), H. tenuisoror (Australian Capital Territory, Wombat Creek, 6 km NE of Piccadilly Circus), H. textila (Queensland, Laceys Creek, 10 km SE El Arish), H. tridisca (Queensland, Mt. Hemmant), H. triloba (Queensland, Mulgrave River, Goldsborough Road Crossing), H. wattsi (Northern Territory, Holmes Jungle, 11 km NE by E of Darwin), H. weiri (Western Australia, 14 km SbyE Kalumburu Mission), H. zwicki (Queensland, Clacherty Road, via Julatten).

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49

Beckie, Hugh J., Robert H. Gulden, Nasir Shaikh, Eric N. Johnson, Christian J. Willenborg, Clark A. Brenzil, Scott W. Shirriff, Chris Lozinski e Greg Ford. "Glyphosate-resistant kochia (Kochia scoparia L. Schrad.) in Saskatchewan and Manitoba". Canadian Journal of Plant Science 95, n. 2 (marzo 2015): 345–49. http://dx.doi.org/10.4141/cjps-2014-328.

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Beckie, H. J., Gulden, R. H., Shaikh, N., Johnson, E. N., Willenborg, C. J., Brenzil, C. A., Shirriff, S. W., Lozinski, C. and Ford, G. 2015. Glyphosate-resistant kochia (Kochia scoparia L. Schrad.) in Saskatchewan and Manitoba. Can. J. Plant Sci. 95: 345–349. Previous surveys have documented the occurrence of glyphosate-resistant (GR) kochia in Alberta in 2011 and 2012. To determine the incidence of GR kochia in Saskatchewan and Manitoba, a stratified-randomized survey of 342 sites (one population per site) in southern and central regions of Saskatchewan and a similar survey of 283 sites in southern Manitoba was conducted in the fall of 2013. Mature plants were collected, seed threshed, and progeny screened by spraying with a discriminating glyphosate dose of 900 g ae ha–1 under greenhouse conditions. Screening confirmed 17 GR kochia populations in nine municipalities in west-central or central Saskatchewan, but only two GR populations from different municipalities in the Red River Valley of Manitoba. While the majority of GR kochia populations in Saskatchewan originated in chemical-fallow fields, some populations were found in cropped fields (wheat, Triticum aestivum L.; lentil, Lens culinaris Medik.; GR canola, Brassica napus L.) and non-cropped areas (oil well, roadside ditch). In Manitoba, the two populations occurred in fields cropped to GR corn (Zea mays L.) and soybean (Glycine max L. Merr.). Agronomic and economic impact of this GR weed biotype is compounded because of consistent multiple resistance to acetolactate synthase-inhibiting herbicides. However, GR kochia is susceptible to dicamba, an increasingly important auxinic herbicide used for control of this multiple-resistant weed biotype.

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50

Vandall, T. A., e D. T. A. Symons. "Paleomagnetism of Archean granites and Matachewan dikes in the Wawa Subprovince, Ontario: reevaluation of the Archean apparent polar wander path". Canadian Journal of Earth Sciences 27, n. 8 (1 agosto 1990): 1031–39. http://dx.doi.org/10.1139/e90-107.

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Paleomagnetic measurements have been completed on 400 specimens from dated Archean granites and Matachewan dikes in the Michipicoten and Gamitagama greenstone belts in the western Wawa Subprovince of the Superior Province, Ontario. Detailed alternating-field and thermal step demagnetization analyses were used to isolate stable remanence directions. A single-component remanence was isolated within three adjacent dated granitic plutons on the eastern margin of the Michipicoten belt, including the Hawk Lake trondhjemite, the Southern external granite, and the Eastern external granite (HSE). The maximum possible age for this remanence is constrained by the intrusion of the last pluton at 2694 Ma. The corresponding HSE paleopole is located at 10°W, 41°S (dp = 8°, dm = 13°). A second paleopole, NB, is derived from the Northern external granite and the Baldhead River quartz monzonite, which give U–Pb zircon ages of 2662 and 2668 Ma, respectively. Their single-component remanence defines a paleopole on the Archean apparent polar wander path (APWP) at 15°E, 27°S (dp = 8°, dm = 13°), with a maximum possible age of 2.66 Ga. A third paleopole, GD, is derived from the north-northwest-trending Gamitagama diabase dikes and yields a position of 57°E, 41°N (dp = 7°, dm = 14°), which agrees with poles determined by other workers from the 2454 Ma Matachewan dike swarm. The GD pole, along with previously determined Matachewan dike poles, demonstrates that a tectonically stable craton has existed since intrusion of this extensive dike swarm, and it improves the precision of the 2454 Ma Matachewan pole on the APWP. These poles, when compared with coeval poles from the eastern side of the Kapuskasing Structural Zone in the Superior Province, imply no tectonic rotation or translation between the Wawa and Abitibi subprovinces along this Early Proterozoic structure.

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