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Using the River Habitat Survey method in forecasting effects of river restoration

100%
Kiraga M., Popek Z.
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
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2014
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tom 46
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nr 2
Research presents usability of the River Habitat Survey (RHS) evaluation method in forecasting effects of the Zielawa River restoration, performed in selected section between 18 + 960 km and 19 + 460 km. The EU so-called Water Framework Directive signalizes necessity of achieving a good ecological status of European rivers in the immediate future. Accordingly, river restoration is the main tool for already technically regulated rivers’ quality upgrading. Present research contains a collation of four proposed restoration works variants and the ecological evaluation of chosen river reach before and after initiating restoration works in accordance to various variants, using the RHS method. The conclusion is fact, that in dependence of established variant it is possible to receive improvement of ecological class from present Class V to Class IV (variants 1 and 2) or Class III (variants 3 and 4).
2

Hydromorphological valorisation of the Bochotniczanka River valley as a potential valuable ecological corridor in the Lublin region

75%
Maslanko W., Sender J.
Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego
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2014
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tom 11
3

Spread of alien Impatiens glandulifera along rivers invaded at different times

63%
Malikova L., Prach K.
International Journal of Ecohydrology and Hydrobiology
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2010
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tom 10
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nr 1
Invasion of Impatiens glandulifera was reconstructed along rivers in the Czech Republic, central Europe, based on floristic records. The occurrence was assessed along river banks, outside the river banks, and along tributaries downstream from the first records of the species in 1902, 1903, 1978 and 1995, respectively. The following main results were obtained: (a) The species nowadays occupies 77% of the river length in the country. (b) The rivers, investigated in detail, did not differ in the occurrence of the species along the river banks. (c) There were some significant relationships between the penetration of I. glandulifera far from the river banks both in terms of the lateral dimension in the main valley, and upstream along the tributaries, and the time of the first occurrence of the species on the river. (d) It took approximately 20 years from the first occurrence on the main river and the start of spread along the tributaries. The process of invasion is still in progress after about one century and further spread is expected.
4

The effects of small-scale impoundments and bank reinforcing on fish habitat and composition in semi-natural streams

63%
Monaghan K. A., Fonseca M. M., Domingues I., Soares A. M. V. M.
Polish Journal of Ecology
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2008
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tom 56
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nr 4
647-657
We studied the fish assemblages of thirty one, 2nd–4th order “least-impacted” streams with a varying degree of low-level management in central Portugal, using a standardised survey to document the river habitat. Channel, banks and riparian landuse, described separately according to principal component scores, were significantly related to altitude, slope and management intervention. Species diversity was low, represented by four endemic, four pan-European and one exotic species. TWINSPAN classification distinguished 3 community types, characterised by their dominant species: trout (Salmo trutta L.), chub (Leuciscus carolitertii Doadrio) and “roach” (Squalius alburnoides Steindachner and Chondrostoma oligolepis Robalo). Community types were associated with environmental differences with PC Channel scores higher at trout sites compared to other classification groups, whilst PC Bank-1 scores, temperature and conductivity were significantly different at trout compared to “roach” sites. Ecologically important habitat features were, in turn, related to landscape (map-derived) parameters and the extent of channel and bank management. The mis-classification of sites in discriminant analysis was related to management intervention, indicating the potential difficulty in the assignment river-community types for the biological monitoring of fish communities in these stream types.
5

Food and feeding of Viviparus viviparus [L.] [Gastropoda] in dam reservoir and river habitats

51%
Jakubik B.
Polish Journal of Ecology
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2009
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tom 57
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nr 2
321-330
Studies on feeding of V. viviparus were carried out in the years 1995–2005 in dam reservoir (Zegrzyński Reservoir, Central Poland, 60 km long, mean depth ca 3.5 m, maximum depth at the dam up to 9 m, mean retention time from 1 to 15 days) and in the outlets of its tributaries (the Bug, Narew and Rządza rivers), in the Narew River and – in the years 2003–2006 – also in oxbow lakes of the Bug River. Sex ratio and size structure of snails were estimated. Both the content of intestines (detritus, algae, inorganic matter) and the gut fulfilment were analysed. Performed multi-factor analysis showed the effect of habitat, season and snail size (estimated from shell height) on food mass in the gut. Snails from dam reservoir and outlet stretches of three rivers showed the largest food mass in the gut. Intestines of snails from rivers and oxbow lakes were less filled. The largest food volumes were found in spring and summer. Only in viviparids from oxbow lakes the largest food mass in the gut was noted in the autumn. Food mass in the gut was largest in snails of the I (<8 mm) and IV (20–35 mm) size class. Food mass was similar in females and males. Differences were, however, noted in the ingested food mass between fertile and infertile females which was smaller in the former. In all studied sites the snails fed mainly on detritus which constituted from 70 to 90% of food mass ingested of all individuals. Detritus abundance in studied habitats might result in using it by snails as obligatory though low-energetic food source. Detritus contributed more to the food of viviparids from Zegrzyński Reservoir and from oxbow lakes, slightly less – to the food of those from outlet stretches of rivers and from the Narew River. Algae contributed from 5% (Zegrzyński Reservoir) to 15% (the Narew River) to the food mass in snail guts. Apart from diatoms, green algae, dinoflagellates and chrysophytes, also cyanobacteria were found in snail food mass. Green algae (46% of all algae) and diatoms (37% of all algae) constituted the largest part of viviparids algal diet in the reservoir. The share of chrysophytes and dinoflagellates made about 10%. More diatoms (up to 48%) and less green algae (up to 25%) were found in snails from outlet stretches of rivers. Guts of snails from the Narew River contained mainly diatoms (over 50%) and green algae (30%). Gut content of snails from oxbow lakes was dominated by green algae (50% of all algae) and diatoms (35% of all algae). Inorganic matter in a form of mineral particles contributed least to the food of snails in the reservoir and in oxbow lakes (ca 5%) in comparison with snails from other sites. No food of animal origin was found. In general, it can be stated that the amount of food mass ingested and its composition differed rather slightly among studied habitats, seasons and individuals.
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