Järvede tervendamine Eestis: ajalugu ja arenguvõimalused
Laen...
Kuupäev
2015
Kättesaadavus
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Eesmärgiks oli koguda infot 19 Eestis tervendatud järve kohta ja koondada see ühtsesse
andmebaasi. Ühtlasi analüüsiti järvede tervendamise edukust Eestis.
Käesoleva töö oluliseimad järeldused on:
1. Järvede seisund üldiselt paraneb tervendustööde tulemusel. Püsiva tulemuse saavutamiseks
tuleb tervendamise meetmeid kombineerida ja sageli ka korduvalt rakendada.
2. Järvede tervendamise praktika kohta on vähe infot. Eriti vähe on infot selle kohta, mis on
toimunud pärast tööde läbiviimist järves ja valgalal.
Käesoleva töö jaoks polnud võimalik leida piisavalt avaldatud andmeid, et uurida järvede seisundi
paranemist tervendamise meetmete kaudu, mistõttu on analüüsida järvede tervendamise edukust
Eestis.
Kogutud andmebaasi alusel võib välja tuua 3 positiivset ja 3 negatiivset näidet järvede tervendamise
kohta. Positiivsete näidetena saab esile tõsta kalamajanduslikud ümberkorraldused Võrtsjärves,
jääkreostuse eemaldamise Raadi järvest ja Vööla mere seisundi parandamise veevahetuse
suurendamise teel ning plaanid tööde jätkamiseks järve ökoloogilise seisundi parandamise nimel.
Ebaõnnestumise näited on Ermistu järv, kus kalamajanduslike eesmärkide saavutamiseks muudeti
järv ummuksile jäävaks makrofüüdijärveks, Väimela Alajärv, kus püüti ebaõnnestunult muda välja
pumbata ja Harku järv, kus biomanipulatsioonile ei eelnenud väliskoormuse vähendamist ja kus
biomanipulatsioon rahastuse puudusel katkes.
Käesoleva töö autor soovitab alati pärast järvedes tehtud töid koostada aruanne järve seisundi ja
valgalal toimunud muutustest koos soovituste ja analüüsidega, sealhulgas ülevaade
reostuskoormuse vähenemise meetmetest valgalal. Soovitan ka vastavaid aruandeid avaldada, kuna
see võib aidata paranda järvede tervendamise kvaliteeti parandada
This research paper is based on European Interregional Cooperation programme INTERREG IVC project LakeAdmin. The aim of the LakeAdmin project is to improve lake restoration quality in European Union. One of the project goal was to collect and compile information about lake restoration practices into open access database. The aim of this research paper was to collect information about 19 Estonian lake restoration projects and compile them into one database and to analyse the success of lake restoration projects in Estonia. Lakes’ physical and chemical characteristics and literature were analysed to assess the lake restoration success. There was not much information about Estonian lakes restoration projects, especially after the restoration. Taking into account analysed information, it is possible that water quality in restored lakes improved. For long-lasting effects it is necessary to combaine and repeat different lake restoration measures. Lake restoration projects were unsuccessful because of unfinished operations and project leaders did not see forward the future. Based on compiled information is possible to point out three positive examples and three negative examples of lake restoration projects in Estonia. The positive example are lake Võrtsjärv, lake Raadi and lake Vööla. In Lake Võrtsjärv, fish stocks increased after bottom trawling was prohibited. The oil-contaminated sediments were removed from lake Raadi and in lake Vööla, lake’s ecological status changed from poor to moderate when water exchange with sea was improved. In lake Ermistu fishes can die due to oxygen depletion in winter because of water level drawdown which caused overgrowth of macrophytes. In Väimela Alajärv restoration project failed and lake’s ecological status in nowadays is moderate. The pollution was not reduced before biomanipulation in lake Harku and biomanipulation was canceled after ended funding After lake restoration projects, I recommend making a report on lake’s ecological status and watershed with recommendations and analysis of physical and chemical properties which can show lake status exchange. It is necessary to make publicitations about the lake restoration measures, beacause there could be a lot of knowledge which can improve the lake restoration quality.
This research paper is based on European Interregional Cooperation programme INTERREG IVC project LakeAdmin. The aim of the LakeAdmin project is to improve lake restoration quality in European Union. One of the project goal was to collect and compile information about lake restoration practices into open access database. The aim of this research paper was to collect information about 19 Estonian lake restoration projects and compile them into one database and to analyse the success of lake restoration projects in Estonia. Lakes’ physical and chemical characteristics and literature were analysed to assess the lake restoration success. There was not much information about Estonian lakes restoration projects, especially after the restoration. Taking into account analysed information, it is possible that water quality in restored lakes improved. For long-lasting effects it is necessary to combaine and repeat different lake restoration measures. Lake restoration projects were unsuccessful because of unfinished operations and project leaders did not see forward the future. Based on compiled information is possible to point out three positive examples and three negative examples of lake restoration projects in Estonia. The positive example are lake Võrtsjärv, lake Raadi and lake Vööla. In Lake Võrtsjärv, fish stocks increased after bottom trawling was prohibited. The oil-contaminated sediments were removed from lake Raadi and in lake Vööla, lake’s ecological status changed from poor to moderate when water exchange with sea was improved. In lake Ermistu fishes can die due to oxygen depletion in winter because of water level drawdown which caused overgrowth of macrophytes. In Väimela Alajärv restoration project failed and lake’s ecological status in nowadays is moderate. The pollution was not reduced before biomanipulation in lake Harku and biomanipulation was canceled after ended funding After lake restoration projects, I recommend making a report on lake’s ecological status and watershed with recommendations and analysis of physical and chemical properties which can show lake status exchange. It is necessary to make publicitations about the lake restoration measures, beacause there could be a lot of knowledge which can improve the lake restoration quality.
Kirjeldus
Märksõnad
magistritööd