scholarly journals Resumption of natural reproduction of the Adriatic sturgeon in the River Po

Oryx ◽  
2021 ◽  
Vol 55 (6) ◽  
pp. 816-816
Author(s):  
Leonardo Congiu ◽  
Elisa Boscari ◽  
Samuele Pagani ◽  
Marco Gazzola ◽  
Paolo Bronzi
2020 ◽  
pp. 1-19
Author(s):  
Cinalberto Bertozzi ◽  
Fabio Paglione

The Burana Land-Reclamation Board is an interregional water board operating in three regions and five provinces. The Burana Land-Reclamation Board operates over a land area of about 250,000 hectares between the Rivers Secchia, Panaro and Samoggia, which forms the drainage basin of the River Panaroand part of the Burana-Po di Volano, from the Tuscan-Emilian Apennines to the River Po. Its main tasks are the conservation and safeguarding of the territory, with particular attention to water resources and how they are used, ensuring rainwater drainage from urban centres, avoiding flooding but ensuringwater supply for crop irrigation in the summer to combat drought. Since the last century the Burana Land-Reclamation Board has been using innovative techniques in the planning of water management schemes designed to achieve the above aims, improving the management of water resources while keeping a constant eye on protection of the environment.


2018 ◽  
Vol 53 (5) ◽  
pp. 1070-1079
Author(s):  
Zh.A. Shirinyan ◽  
◽  
M.V. Pushnya ◽  
E.Yu. Rodionova ◽  
E.G. Snesareva ◽  
...  

2020 ◽  
pp. 68-77
Author(s):  
O.N. CHERNYKH ◽  
◽  
A.V. RBURLACHENKO

Recommendations are presented for solving issues that arise in the design and operation of tubular transport crossings of corrugated metal structures through spawning streams while ensuring the safety and natural reproduction of fish stocks. There are discussed the results of experimental studies of culverts made of metal corrugated pipes with a normal and spiral shape of corrugation the bottom of which is buried and filled with suitable granular material to the level of the natural channel of a small watercourse. It is established that when 10% of the area of the corrugated pipe is occupied by stone filling, its throughput is reduced by about 10-12%. Based on the review of the existing literature and the results of laboratory experiments, data is provided to estimate the values of the roughness coefficients of the composite cross-section of a single-point junction and directions for future research on culvert reclamation are outlined. Studying of the structure of the velocity distribution in culverts can lead to the improved conditions for fish passage without installing special structural elements in the transit path of the fish passage structure.


2015 ◽  
Vol 87 (2) ◽  
pp. 487-493 ◽  
Author(s):  
M. Hundt ◽  
A. Scharbert ◽  
U. Weibel ◽  
G. Kuhn ◽  
K. Metzner ◽  
...  

2003 ◽  
Vol 60 (12) ◽  
pp. 1552-1574 ◽  
Author(s):  
Charles R Bronte ◽  
Mark P Ebener ◽  
Donald R Schreiner ◽  
David S DeVault ◽  
Michael M Petzold ◽  
...  

Changes in Lake Superior's fish community are reviewed from 1970 to 2000. Lake trout (Salvelinus namaycush) and lake whitefish (Coregonus clupeaformis) stocks have increased substantially and may be approaching ancestral states. Lake herring (Coregonus artedi) have also recovered, but under sporadic recruitment. Contaminant levels have declined and are in equilibrium with inputs, but toxaphene levels are higher than in all other Great Lakes. Sea lamprey (Petromyzon marinus) control, harvest limits, and stocking fostered recoveries of lake trout and allowed establishment of small nonnative salmonine populations. Natural reproduction supports most salmonine populations, therefore further stocking is not required. Nonnative salmonines will likely remain minor components of the fish community. Forage biomass has shifted from exotic rainbow smelt (Osmerus mordax) to native species, and high predation may prevent their recovery. Introductions of exotics have increased and threaten the recovering fish community. Agencies have little influence on the abundance of forage fish or the major predator, siscowet lake trout, and must now focus on habitat protection and enhancement in nearshore areas and prevent additional species introductions to further restoration. Persistence of Lake Superior's native deepwater species is in contrast to other Great Lakes where restoration will be difficult in the absence of these ecologically important fishes.


Author(s):  
P. Tongiorgi ◽  
E. Fregni ◽  
M. Balsamo

During 1996–1997 a systematic sampling programme was carried out in brackish coastal lakes and lagoons and in the delta of the River Po. In six of the nine collecting locations, 12 species of Gastrotricha were identified. One species, Chaetonotus ichthydioides, is new to science; another three species, the chaetonotidans Heterolepidoderma foliatum and the macrodasyidans Dendrodasys ponticus and Turbanella cf. pontica, and one macrodasyidan genus, Paradasys (P. subterraneus), were found in Italy for the first time. The unusual morphology of some of the species identified shows that Gastrotricha colonized brackish waters from both marine and freshwater habitats.


1992 ◽  
Vol 125 (2) ◽  
pp. 175-206
Author(s):  
Maurizio Battegazzore ◽  
Robert C. Petersen Jr. ◽  
Giampaolo Moretti ◽  
Bruno Rossaro

1989 ◽  
Vol 46 (2) ◽  
pp. 277-286 ◽  
Author(s):  
Steven P. Gloss ◽  
Carl L. Schofield ◽  
Robert L. Spateholts ◽  
Barbara A. Plonski

Brook trout (Salvelinus fontinalis) were stocked into two previously acidic (pH 4.5–5.2) Adirondack Mountain lakes, Woods Lake and Cranberry Pond, following liming in June, 1985. Age 0+ Temiscamie × Domestic hybrid brook trout were stocked at 200∙ha−1 with one-half of the fish selected for presumed acid tolerance. Age 1+ Temiscamie strain brook trout were also stocked at 50∙ha−1. Liming increased pH to well above 7 and alkalinity to over 200 μeq∙L−1. Growth and condition of stocked fish were good while water quality conditions remained suitable. However, in Cranberry Pond, which reacidified 6 mo after liming, both growth and survival declined dramatically. Much of the population loss was due to emigration. Annual survival in Woods Lake averaged 35 and 25% for the age 0+ and 1+ fish, respectively. Initially large invertebrates made up most of the diet for stocked fish. These taxa were replaced by zooplankton within a few months. Limited natural reproduction was associated with low velocity groundwater inflows and high acidity in tributary streams. Fry emergence from artificial spawning substrates placed in Woods Lake peaked well after snowmelt inflows which produced toxic conditions in littoral areas.


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