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Fluctuating asymmetry of invertebrate populations as a biological indicator of environmental quality.
1993
Clarke G.M.
Contents of heavy metals in the sediments of fish-ponds and their possible mobility because of changing physical-chemical factors of environment
2001
Kezic, V. | Lompar, O. | Lehoczki, I. | Tohati, L. | Stanic, A. | Jovanic, S. (Zavod za zastitu zdravlja, Subotica (Yugoslavia))
One of the very dangerous pollution of environment are heavy metals. They are "indestructible" at the condition which leads at the environment. Pollution of heavy metals is irreversible process, except if they are physical removed from the environment which they are polluting. We determinated heavy metals (Pb, Cd, Cu, Zn, Cr, Ni and Co) in the mud of three fish ponds by means of sequential extraction, because of possible mobility in the mud and its concentration increase in the water. This method was selected because we wanted to determine distribution of heavy metals by substrates, and analyse was worked by the method of AAS. The results are showing that the concentration of all metals is in the extent of "natural phone" of lakes sediment.
Mostrar más [+] Menos [-]Inadequacy of stabilization ponds treatment as manifested by the effects of Khirbet es-Sumra effluent on the groundwater quality of the surrounding area
1991
Bannayan, H. (Jordan Univ., Amman (Jordan). Water Research and Study Centre)
Three wells lying downstream of the Kirbet es-Samra sewage treatment plant (KS) waste stabilization ponds, and two wells lying upstream of them were monitored. Historic results over the two past decades were used in evaluating of KS effluent on the groundwater resources of the area. Prior to 1985, the downstream wells were of high quality, but later the water started to deteriorate. An increases in all parameters was encountered, although initially, the increase in certain parameters was mild and due to overpumping of the well water. Later this increase continued at a much higher rate, although the water table in the area by some 20m with a variety of indications showing domestic wastewater pollution effects. Groundwater measurements indicated a recharge mouth in the KS area and along Wadi Dhuleil. Hence, it can be deducted that a source of inferior water quality is recharging the groundwater and causing this increase in parameters. Since no source of pollution other than KS is encountered in the area, and because the parameters in the groundwater increase towards the KS and Wadi Dhuleil, it can be deducted that the effluent from KS is polluting the groundwater and rendering it unsuitable for almost all purposes. Comparatively, the two sample wells taken upstream of KS showed a mild increase in the water quality parameters until 1981-82, due to overpumping of the well water. But due to several wet years, the water table rose and these values decreased, continuing at a constant level. Since the groundwater flow is in the direction of Wadi Dhuleil, the negative effect of KS on groundwater resources can be clearly seen. If not stopped, this continuous manipulation of the groundwater resources will further pollute the groundwater resources of the entire area
Mostrar más [+] Menos [-]Response of a zooplankton community to insecticide application in experimental ponds: a review and the implications of the effects of chemicals on the structure and functioning of freshwater communities
1998
Hanazato, T. (Suwa Hydrobiological Station, Shinshu University, 5-2-4 Kogandori, Suwa, Nagano 392-0027 (Japan))
Effects of the triazine herbicide, simetryn, on freshwater plankton communities in experimental ponds
1995
Kasai, F. | Hanazato, T. (Regional Environment Division, National Institute for Environmental Studies, Tsukuba, Ibaraki 305 (Japan))
Polychaete-sediment relations in Rayong, Thailand
1999
Meksumpun, C. | Meksumpun, S. (Faculty of Fisheries, Kasetsart University, Chatuchak, Bangkok 10900 (Thailand))
A pond mesocosm study to determine direct and indirect effects of lindane on a natural zooplankton community
1996
Peither, A. | Juttner, I. | Kettrup, A. | Lay, J.P. (GSF-Forschungszentrum fur Umwelt und Gesundheit, Institut fur Bodenokologie, Neuherberg, 85764 Oberschleissheim (Germany))
Fluxes and mass balances of nutrients in a semi-intensive shrimp farm in north-western Mexico
1997
Paez-Osuna, F. | Guerrero-Galvan, S.R. | Ruiz-Fernandez, A.C. | Espinoza-Angulo, R. (Laboratorio de Quimica Marina, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autonoma de Mexico, Apdo. Postal 811, Mazatlan 82000, Sinaloa (Mexico))
Dose-response relationships for the addition of limestone to lakes and ponds in the northeastern United States
1988
Adams, T.B. | Brocksen, R.W.
Recent advances in biogas technology in Cuba
1994
Sanchez, E. (National Center for Scientific Research, La Habana (Cuba)) | Benitez, F. | Travieso, L. | Weiland, P. | Ramos, C. | Milan, Z. | Conde, J.L. | Rovirosa, N. | Montalvo, S. | Lopez, M.