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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Šikšnosparnių (Chiroptera) rudeninės migracijos tyrimai Oderio upės slėnyje pietvakarių Lenkijoje / The research of bat (chiroptera) autumn migration in the oder river valley in southwestern poland

Stefanovič, Violeta 23 December 2014 (has links)
Tyrimai buvo atlikti pietvakarių Lenkijoje, Oderio upės slėnyje Kwiatkowice (Kviatkovice) ir Rzeczyca (Žečica) apylinkėse, pietvakarių Lenkijoje, Žemutinės Silezijos vaivadijoje (Dolnośląskie województwo) 2010 m. Tyrimams pasirinktos penkios vietos: upės vagos šiaurės-pietų kryptis ir vakarų-rytų kryptis,lapuočių miško proskyna, pamiškė, kultūrinė pieva. Tyrimai buvo atlikti naudojant bioakustinį, dviejų detektorių sistemos metodą (Jarzembowski, 2003). Oderio upės slėnyje kiekviename punkte buvo pastatyta po du detektorius. Atstumas tarp detektorių – 10 m, detektoriai nukreipti 45º kampu į viršų, atstumas virš žemės – 2 m. Detektorių nukreipimas 45º kampu į viršų leidžia registruoti daugiau šikšnosparnių, kurie skrenda ir arti vandens, ir žymiai aukščiau. Rūšių apibudinimui naudojama Ahlen (1981) ir Barataud (1996, 2006) metodika. Oderio upės slėnio biotopuose aptiktos aštuonios šikšnosparnių rūšys: šikšniukas mažylis, šikšniukas nykštukas, Natuzijaus šikšniukas, rudasis nakviša, vandeninis pelėausis, kūdrinis pelėausis, Branto pelėausis, vėlyvasis šikšnys. Nustatyta, kad vandeninis pelėausis, šikšniukas mažylis, Natuzijaus šikšniukas naudojasi upės vaga kaip migracijos koridoriumi, bet plačiau slėniu nemigruoja. Rudojo nakvišos nekryptingų perskridimų ir maitinimosi signalų visuose biotopuose buvo daug, tai gali reikšti, kad jis tik maitinasi visuose upės slėnio biotopuose. Vėlyvojo šikšnio ir šikšniuko nykštuko kryptingi perskridimai nustatyti miške ir pamiškėje... [toliau žr. visą tekstą] / We studied migration of bats along Odra river valley in SW Poland for four nights in September 2010. We carried out all-night acoustical observations of bats flying at the river North-Soutth and East-West directions segments, in the forest, grassland and on the outer wood. The direction on bats’ movements were determined on the basis of echolocation sequences order recorded by two frequency division ultrasound detectors. We noted activity for eight species: Myotis daubentonii, M. dasycneme, M. brandti, Nyctalus noctula, Pipistrellus nathusii, P. pipistrellus, P. pygmaeus, Eptesicus serotinus. Our results show that Myotis daubentonii, Pipistrellus nathusii, P. pygmaeus use only the river as the migration corridor, but not all valley of the river. Eptesicus serotinus and P. pipistrellus directional flyings were detected in the forest, but these data were unsufficient to relate the migratory way and the valley of the river. The great amount of undirectional flyings and nutrition signals of Nyctalus noctula in all places shows that this species uses all the valley for nutrition. Our results show that the activities of different bats species for twenty four hours are different at the river. The greatest counts of sequencies for Myotis daubentonii, Nyctalus noctula were registered in the evening: Myotis daubentonii – at 8 p.m., and Nyctalus noctula – at 7 p.m. Activities of Pipistrelus pygmaeus and Pipistrellus nathusii were similar during all night time. No activities of bats were... [to full text]
132

Physical biotopes in representative river channels : identification, hydraulic characterisation and application

Padmore, Catherine Lucy January 1997 (has links)
There is a need to predict the river flow conditions necessary to support instream (and river corridor) biota. Many rivers have their flow regulated in some way and the field of 'habitat hydraulics' (or 'ecohydraulics') has grown up to encourage classification and characterisation of lotic physical environments. This thesis, based on field measurements at eleven sites in Northeast England (which are nationally representative), presents the data nonnally collected for the calibration of the PHABSIM model in alternative ways, to identify and characterise 'physical biotopcs'. These are segregated on the basis of subjectively (visually)-defined flow types. Statistical validation of biotopes as hydraulically discrete units shows them to be defined by a characteristic range of hydraulic variables, especially the Froude number. An investigation of the spatial and temporal variability of biotopes in different channel types and at different flows was carried out (1993-1995), which included the most extreme floods and droughts on record at some sites. The 'biotope approach' is shown to have potential as a reconnaissance approach to the assessment of habitat quality. Despite the success of the biotope approach e.g. in River Habitat Surveys, methodological improvement is still required, notably in the area of hydraulic characterisation by velocity measurements. Hydraulically rough channels and those with substantial macrophyte growth present problems; a logarithmic velocity profile cannot be assumed. A relationship between biotope diversity and stream ecosystem health is suggested; biological surveys are required to determine the direct relationship. This thesis represents a shift from the geomorphological riffle-pool theory to a broader classification of instream hydraulic units. It provides a framework for testing the debate in ecological theory regarding the role of patch dynamics within the continuum of the river environment. The study indicates that an 'environmentally acceptable flow regime' is one which creates a range of biotopes and maintains 'critical biotopes' at periods coinciding with key lifestage events. Flood events are beneficial for their role in 'resetting' the system.
133

Suspended sediment and solutes in the River Lagan catchment, Northern Ireland

Gardiner, T. January 1980 (has links)
No description available.
134

Iodine speciation in the Yarra River estuary

Lin, Jianping January 1992 (has links) (PDF)
An oxygen-deficient (12.8 microM dissolved oxygen and oxygen saturation 5.0-7.4% in the water of the deep hole) isolated water system in the deep hole of the Yarra River estuary was investigated to discover the relationship between iodate and iodide. The iodate concentration in the water of the deep hole was very low (0.039 to 0.062 microM at bottom water, salinity from 26.8-30.0 Practical Salinity Scale, 1978), because iodate reduced to iodide in the water by reducing agents (S2-, Fe2+ and Mn2+) diffused from the sediment of the deep hole. / The concentrations of iodine species in the sediment pore water and suspended material in the water of the deep hole were determined to investigate iodine cycling in the deep hole. The iodine flux from sediment into overlying water in the deep hole was 15.6 micromol/m^2.day. The concentration of total inorganic iodine (iodate+iodide) in the dry suspended material from the water of the deep hole was 0.117 micro mol/g. The water residence time in the deep hole was studied. In winter especially, the seawater of high density may intrude into the deep hole with the highest tides. The seawater remains trapped in the deep hole below the halocline, which allows the development of oxygen-deficient conditions. / It was found that in the deep hole the iodide concentration increase resulted from sediment diffusion (36%), iodate reduction (27%) and release from suspended material (37%) during the water residence time in the water of the deep hole. The iodine cycling in the deep hole was: iodate in the water reduced to iodide by reducing agents diffused from sediment; suspended material containing soluble or particular iodine may release iodide and also trap iodate and iodide from water during precipitation; iodate in the sediment reduced to iodide and iodide diffused from sediment into overlying water. Iodine is accumulated in the isolated water in the deep hole and might be moved out at the next water exchange.
135

Impacts, standards, and perceived crowding on the Deschutes River : extending carrying capacity research /

Whittaker, Douglas P. January 1987 (has links)
Thesis (M.S.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 93-99). Also available on the World Wide Web.
136

Streamflow generation for the Senegal River basin

N'Diaye, Abdoulaye. January 1985 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1985. / Includes bibliographical references (leaves 224-227).
137

The effects of Columbia River stage fluctuations on ground-water levels near Richland, Washington

Cuddy, Alan Stuart, January 1988 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1988. / Includes bibliographical references (leaves 183-185).
138

Paleoflood hydrology of the alluvial Salt River, Tempe, Arizona

Fuller, Jonathan Edward. January 1987 (has links) (PDF)
Thesis (M.S. - Geosciences)--University of Arizona. / Includes bibliographical references (leaves 66-70)
139

The Ord River blueprint for the future : history and prospects of the Ord River settlement, and its application to the development of the empty north.

Meadows, Margaret J. January 1970 (has links) (PDF)
Thesis (B.A. (Hons)) -- University of Adelaide, Dept. of History, 1970.
140

From gravel to sand : downstream fining of bed sediments in the lower river Rhine /

Frings, Roy. January 2007 (has links)
Univ., Diss.--Utrecht, 2007.

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