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Resultados 31-40 de 76
Monitoring and modelling of biosphere/atmosphere exchange of gases and aerosols in Europe
2005
Erisman, Jan Willem | Vermeulen, Alex | Hensen, Arjan | Flechard, Chris R. | Dämmgen, Ulrich | Fowler, David | Sutton, Mark A. | Grünhage, Ludger | Tuovinen, Juha-Pekka
Managing ammonia emissions from livestock production in Europe
2005
Webb, Jim | Menzi, Harald | Pain, B. F. | Misselbrook, Tom H. | Dämmgen, Ulrich | Hendriks, H. | Döhler, Helmut
Efficacy and toxicity of self-polishing biocide-free antifouling paints
2005
Löschau, M. | Krätke, R.
The ban on harmful substances in antifouling paints requires the development of new antifouling strategies. Alternatives should be as effective as conventional paints but of lower toxicity. In the present study two commercially available, self-polishing antifouling paints were examined in order to get information on their antifouling properties and toxicological potential. Efficacy was shown in settlement assays with the marine barnacle species Balanus amphitrite, however, efficacy was related to toxic effects observed on target and non-target organisms. Toxicity of the paint extracts was concentration-dependent and differed according to the paint and the species investigated. Toxicity could at least partially be attributed to zinc leached from the paints. Effects of a water-soluble paint were more pronounced in larvae of B. amphitrite, Artemia salina and in the green algae Dunaliella tertiolecta. Embryos of the freshwater species Danio rerio and Vibrio fisheri were more affected by a paint based on organic solvents
Mostrar más [+] Menos [-]Synthetic- and bio-polymer use for runoff water quality management in irrigated agriculture
2005
Sojka, R.E. | Entry, J.A. | Orts, W.J. | Morishita, D.W. | Ross, C.W. | Horne, D.J.
Low concentrations of synthetic- or bio-polymers in irrigation water can nearly eliminate sediment, N, ortho- and total-P, DOM, pesticides, micro-organisms, and weed seed from runoff. These environmentally safe polymers are employed in various sensitive uses including food processing, animal feeds, and potable water purification. The most common synthetic polymer is anionic, high purity polyacrylamide (PAM), which typically provides 70 - 90% contaminant elimination. Excellent results are achieved adding only 10ppm PAM to irrigation water, applying 1 - 2kgha+1 per irrigation, costing $4 - $12kg+1. Biopolymers are less effective. Using twice or higher concentrations, existing biopolymers are ≈60% effective as PAM, at 2 - 3 times the cost. A half million ha of US irrigated land use PAM for erosion control and runoff protection. The practice is spreading rapidly in the US and worldwide. Interest in development of biopolymer surrogates for PAM is high. If the supply of cheap natural gas (raw material for PAM synthesis) diminishes, industries may seek alternative polymers. Also "green" perceptions and preferences favor biopolymers for certain applications.
Mostrar más [+] Menos [-]Redundance rivers in the confluence of Likorda [Serbia (Serbia and Montenegro)]
2005
Ristanovic, B. E-mail:braristan@yahoo.com | Jokic, I. | Bojanic, D.(Prirodno-matematicki fakultet, Novi Sad (Serbia and Montenegro). Departman za geografiju, turizam i hotelijerstvo)
Redudance rivers are basic hydrographic problem in area of Radjevina. Their appearance to associate for most rivers in the confluence of Likorda river and have character of season. Using method of quantity index the rivers of this region are classified in special hydrological classes. On the basis of this typology the possible models for solution of this problem are given.
Mostrar más [+] Menos [-]Physico-chemical and biological estimation parameters of water quality of the Bovan lake accumulation [Serbia (Serbia and Montenegro)]
2005
Miljanovic, B.(Prirodno-matematicki fakultet, Novi Sad (Serbia and Montenegro). Departman za biologiju i ekologiju) | Djukic, N. | Pujin, V. | Ivanc, A. | Zivic, N. | Milenkovic, P. | Nakic, S.
Water samples for chemical and microbiological analyses as well as material of the water community to be considered in the assessment of qualitative and quantitative composition of phyto- and zooplankton, and bottom fauna were take on 30 May 2001 at two profiles. Judging by the most of the analyzed chemical parameters, with the exception of BOD5 and oxygen saturation values indicating class 2, water of the Bovan lake accumulation belongs to the 1st class of water quality. According to the presence of heterotrophic bacteria, water was characterized as class 1-2 (after Kohl). Also, 6 groups of phyto- and 4 groups of zooplankton were recorded. Relative abundance and qualitative composition values of plankton show that saprobic index ranged from 1.54 to 1.98 pointing out oligo-beta, namely beta-mesosaprobic character of the accumulation. Saprobic index when oligochaetes were considered amounted up to 3.6 (alfa-mesosaprobic water).
Mostrar más [+] Menos [-]Geothermal waters of Ovcar Banja [Serbia (Serbia and Montenegro)] - possibilities of utilization for the purpose of allochthonous fish species rearing
2005
Markovic, G.(Univerzitet u Kragujevcu, Cacak (Serbia and Montenegro). Agronomski fakultet) | Jurakic, Z. | Cirkovic, M. | Maletin, S.
Thermal waters represent an unused natural potential of Serbia. A possible way of utilizing this resource is to carry out the initiative that has been underway over the past several years to use certain thermal waters for the rearing of some allochthnous thermophilic fish species, the most famous among them being the group Tilapia (fam. Cichlidae), authochthonous in Africa and Asia. The analysis of basic physico-chemical properties of the Ovcar Banja (Ovcar Spa) thermal waters (the bed of the Zapadna Morava river, Western Serbia) indicates the possibility of their utilization for this purpose.
Mostrar más [+] Menos [-]Multiannual ecological investigations in the Montenegrin coastal sea [Adriatic sea, Montenegro (Serbia and Montenegro)] and their importance for estimation of the sea-water quality
2005
Regner, D. E-mail:dregner@cg.ac.yu | Vuksanovic, N. | Stjepcevic, B. | Joksimovic, D.(Institut za biologiju mora, Kotor (Serbia and Montenegro))
In this paper, there were discussed the results of ecological investigation of the Montenerin part of the Adriatic sea during the period 1996-2003. Evaluation of the sea-water quality was done in the coastal sea. The importance of multiannual ecological investigations was emphasized, too.
Mostrar más [+] Menos [-]Activities for implementation of protection with the aim of optimal exploitation of marine biological resources along Montenegrin coast [Adriatic sea, Montenegro (Serbia and Montenegro)]
2005
Regner, S. E-mail:regners@cg.ac.yu | Mandic, S. | Joksimovic, A.(Institut za biologiju mora, Kotor (Serbia and Montenegro))
In the last few years, in Montenegro there were positive movements into fulfilling the principles of sustainable marine fishery, primarily throught introducing the Law on Marine Fishing and its rules. Institure of Marine Biology in Kotor, Montenegro, in cooperations with the Ministry for Agriculture, Forestry and Water Management of the Republic of Montenegro, works on undertaking of the measures that may ensure optimal regulation of fishing. These measures were based on scientific research, particularly on the estimates of parameters of population dynamics, biomass and maximum biologically sustainable utilization of economically important species on Montenegrin coast.
Mostrar más [+] Menos [-]Contribution to the knowledge of phytoplankton of Kotor bay [Adriatic sea, Montenegro (Serbia and Montenegro)] [during] the winter season 2004
2005
Vuksanovic, N.(Institut za biologiju mora, Kotor (Serbia and Montenegro)) E-mail:nvuksanovic@ibmk.org | Krivokapic, S.(Univerzitet Crne Gore, Podgorica (Serbia and Montenegro). Prirodno-matematicki fakultet, Odsjek za biologiju) E-mail:sladjana69@yahoo.com
There are presented the results of investigations carried out in the Kotor Bay (Adriatic Sea), Montenegro (Serbia and Montenegro) during the winter months of 2004. The highest value of microphytoplankton as a greater size-fraction of phytoplankton is found in the surface layer during March (1.4 x 10**7 cells/cubic dm). The main edificator was diatomic species Skeletonema costatum with relative percentage about 100%. Obtained results point out that Kotor Bay belongs to the highest eutrophic or extreme eutrophic area. Similar result is found in the same period twenty years ago.
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