EJPAU 2005. Tandyrak R. CHEMISM OF BOTTOM SEDIMENTS FROM A LAKE TREATED WITH VARIOUS RESTORATION TECHNIQUES

Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.

2005
Volume 8
Issue 4

Topic:

Environmental Development

ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES

Tandyrak R. 2005. CHEMISM OF BOTTOM SEDIMENTS FROM A LAKE TREATED WITH VARIOUS RESTORATION TECHNIQUES, EJPAU 8(4), #73.
Available Online: http://www.ejpau.media.pl/volume8/issue4/abs-73.html

CHEMISM OF BOTTOM SEDIMENTS FROM A LAKE TREATED WITH VARIOUS RESTORATION TECHNIQUES

Renata Tandyrak
Faculty of Environmental Protection and Fishery, University of Warmia and Mazury, Olsztyn, Poland

ABSTRACT

The small (7 ha) and deep (23 m) Lake Starodworskie in Olsztyn, with restricted water dynamics, is an object that was already used a few times for restoration experiments.

In 1967–68, 1972–74 and 1986–87 the lake was artificially aerated with thermal destratification, in 1988–89 it was aerated without the thermal stratification destruction, in 1994 and 1995 phosphorus was inactivated in the lake, using aluminium sulfate. This paper investigates into the effects of restoration, especially of introduction of many tonnes of chemicals, on the bottom sediments and inhibition of P internal loading.

Sampling station 1, located in the shallowest part of the lake, was characteristic of good oxygen conditions, highest content of silica and lowest content of other measured parameters. The highest concentrations of organic matter, aluminium, iron, calcium and phosphorus were not found in the deepest spot but on sampling station 2. Assumingly, it was caused by the artificial aeration and the aerator’s placement over the deepest spot, and by the deposits replacement to the shallower bottom areas.

Significant correlations were determined between organic matter content and calcium (r = 0.813) and phosphorus (r = 0.997). Additionally determined were the correlations between Al-PO₄ and aluminium (r = 0.575), organic matter (r = 0.923) and total P (r = 0.696). There is also a significant correlation between the content of Al-PO₄ in the bottom sediments and phosphorus concentration in the interstitial waters (r = 0.798).

In the sediment cores, sampled from the area subjected to the inactivation experiment, the layer of aluminium hydroxide formed during the treatment was still observable. The sediments of approximately 4 cm, deposited on top, were created during the 7 years after the restoration. Since the layer of hydroxide makes up a physical barrier inhibiting phosphorus release, the process can occur only from fresh sediments.

Key words: lake, restoration, bottom sediments, organic matter, phosphorus.

Renata Tandyrak
Faculty of Environmental Protection and Fishery,
University of Warmia and Mazury, Olsztyn, Poland
Prawochenskiego 1, 10-720 Olsztyn, Poland
email: renatat@uwm.edu.pl

Responses to this article, comments are invited and should be submitted within three months of the publication of the article. If accepted for publication, they will be published in the chapter headed 'Discussions' and hyperlinked to the article.