scholarly journals Kootenay Lake Fertilization Experiment, Year 15 (North Arm) and Year 3 (South Arm) (2006) Report

2009 ◽  
Author(s):  
E.U. Schindler ◽  
D. Sebastian ◽  
G.F. Andrusak
Keyword(s):  
Fertilization Experiment ◽  
Kootenay Lake ◽  
Lake Fertilization

Restoration of an Interior Lake Ecosystem: the Kootenay Lake Fertilization Experiment

1997 ◽  
Vol 32 (2) ◽  
pp. 295-324 ◽  
Author(s):  
Ken Ashley ◽  
Lisa C. Thompson ◽  
David C. Lasenby ◽  
Laurie McEachern ◽  
Karen E. Smokorowski ◽  
...  
Keyword(s):  
Inorganic Nitrogen ◽  
Nutrient Retention ◽  
Lake Ecosystem ◽  
Kokanee Salmon ◽  
Fertilization Experiment ◽  
The North ◽  
Trout Population ◽  
Zooplankton Density ◽  
Reservoir Construction ◽  
Kootenay Lake

Abstract Kootenay Lake, B.C. (395 km2), has experienced a series of major perturbations in the past 50 years, resulting in the 1980s’ collapse of South Arm kokanee salmon stocks and a dramatic decrease in the abundance of North Arm stocks. Historical data indicate the collapse was due to reservoir construction together with subsequent impoundment and nutrient retention on both main inflow tributaries (Kootenai and Duncan rivers) to Kootenay Lake, combined with the introduction of an exotic mysid shrimp which is an efficient competitor with kokanee for zooplankton. Nutrients (47.1 t of P and 206.7 t of N) are now being added annually to the 174 km2 North Arm of Kootenay Lake (271.3 mg-m-2 P and 1,190.5 mg-m-2 N) in a 5-year (1992-96) experiment with the goal of restoring historical kokanee salmon biomass and productivity. The concentration of total phosphorus in the North Arm currently ranges from 4–10 µg-L-1 P, which indicates oligotrophic to mesotrdphic conditions, whereas the concentration of dissolved inorganic nitrogen remains in the oligotrophic range (i.e., <200 mg L-1 N) throughout the year. The seasonal mean zooplankton density observed in 1994 was higher than in 1992 and 1993, and similar to the highest densities observed from 1972 to 1984. Cladocerans comprised about 7.5% of the zooplankton in the North Arm in 1994, 12% in 1993 and 7.5% in 1992 as compared with less than 5% between 1949 and 1991. Combined North Arm kokanee escapement (Lardeau River and Meadow Creek) was 1.25 million fish in 1994 and was the highest observed since 1986, but lower than some escapements observed in the 1970s. Kokanee spawner size and fecundity have also increased. No significant trends have been observed in the Gerrard rainbow trout population. To date, the fertilization experiment has been successful at increasing the abundance of clado-ceran zooplankton and restoring kokanee populations in the North Arm of Kootenay Lake.

scholarly journals Long-term field fertilization experiment with energy willow (Salix sp.) − Elemental composition and chlorophyll fluorescence in the leaves

2018 ◽  
Vol 67 (1) ◽  
pp. 91-103
Author(s):  
László Simon ◽  
Marianna Makádi ◽  
György Vincze ◽  
Zsuzsanna Uri ◽  
Katalin Irinyiné Oláh ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Energy Crop ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Fertilization Experiment ◽  
Nitrogen Concentrations ◽  
Set Up ◽  
Leaf Chlorophyll Fluorescence ◽  
Term Field

A small-plot long-term field fertilization experiment was set up in 2011 with willow (Salix triandra x Salix viminalis ’Inger’) grown as an energy crop in Nyíregyháza, Hungary. The brown forest soil was treated three times (in June 2011, May 2013, May 2016) with municipal biocompost (MBC), municipal sewage sludge compost (MSSC) or willow ash (WA), and twice (June 2011, May 2013) with rhyolite tuff (RT). In late May – early June 2016 urea (U) and sulphuric urea (SU) fertilizers were also applied to the soil as top-dressing (TD). These fertilizers and amendments were also applied to the soil in 2016 in the combinations; MBC+SU, RT+SU, WA+SU and MSSC+WA. All the treatments were repeated four times. In July 2016 the highest nitrogen concentrations in willow leaves were measured in the U (3.47 m/m%) and SU (3.01 m/m%) treatments, and these values were significantly higher than the control (2.46 m/m%). An excess of nitrogen considerably reduced the Zn uptake of the leaves, with values of 39.5 μg g-1 in the U treatment, 53.4 μg g-1 in the SU treatment, and 63.5 μg g-1 in the control. All other amendments or TDs, except for WA, enhanced the specific potassium concentrations in willow leaves compared to the control. No significant quantities of toxic elements (As, Ba, Cd, Pb) were transported from soil amendments or TDs to the willow leaves. In July 2016 the most intensive leaf chlorophyll fluorescence was observed in the MSSC and MSSC+WA treatments.

River-Induced Transport in Kootenay Lake

1995 ◽  
Vol 121 (11) ◽  
pp. 830-837 ◽  
Author(s):  
Craig L. Stevens ◽  
Paul F. Hamblin ◽  
Gregory A. Lawrence ◽  
Farrell M. Boyce
Keyword(s):  
Kootenay Lake

Kootenay Lake

1978 ◽  
Author(s):  
Keyword(s):  
Kootenay Lake
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