Quaternary landforms and basin morphology control the natural eutrophy of boreal lakes and their sensitivity to anthropogenic forcing

Both natural and anthropogenic changes in boreal lakes have been studied utilizing paleolimnological methods, but the spatial variation in the natural conditions of lakes and its connection to geological factors has drawn less attention. Our aims were to examine the spatial distribution of naturally eutrophic lakes on the previously glaciated terrain of central-eastern Finland and the relationship between pre-human disturbance water quality and geological factors related to the basins and their catchments. Furthermore, we studied the pre- to post-human disturbance changes in the diatom assemblages and water quality of 48 lakes (51 sampling sites) across the pre-disturbance phosphorus gradient by using the top-bottom sampling approach and multivariate statistics. According to our results, naturally eutrophic boreal lakes are more common than previously thought, occurring on fine-grained and organic Quaternary landforms, including fine-grained till. Our study emphasizes the importance of the previously overlooked matter of till grain-size variation as a driver behind the spatial variation in the natural trophic states of boreal lakes. The location of a lake in the hydrologic landscape and basin morphology appear to be important factors as well. Shallow, naturally eutrophic lakes with short water residence times and high catchment area to lake area and volume ratios have been particularly sensitive to anthropogenic forcing. Our results indicate that cultural eutrophication is not the only water protection challenge for the relatively remote and dilute boreal lakes, but salinization and alkalinization are also serious threats that should be taken into account. Therefore, it is crucial to consider the notable variation in the natural conditions of boreal lakes in addition to mitigating the effects of anthropogenic forcing, such as nutrient loading, catchment erosion, salt pollution, and climate change, in order to achieve efficient water protection.</p

Geologian tutkimuskeskus, Opas 58 -Geological Survey of Finland

To achieve the &quot;good surface water status&quot; required by the EU Water Framework Directive, we first need to identify reference states for our lakes. Bennion (2011) suggests the time before intensifying human activity due to the onset of rapid industrialization as a reference point. In determining the past reference conditions for a lake, the lack of undisturbed reference lakes can often be overcome by using palaeoecological predictive models, i.e. transfer functions (see e.g. Anderson 1995). However, the models may suffer from poor performance in environmentally atypical areas. We propose that these challenges could be alleviated by developing a targeted model with a training set that consists of modern microfossil calibration samples and corresponding water quality data from the area of interest. We tested this targeted approach in the Iisalmi region, central-eastern Finland, by developing a diatom-total phosphorus transfer function for the shallow, humic and conspicuously eutrophic lakes in the area. The fossil samples for determining the reference conditions were selected from below a depth where magnetic susceptibility notably increased towards the sediment surface. We interpreted this increase to represent intensified erosion caused by human activity. The resulting phosphorus reconstructions suggest that human activity has only induced significant eutrophication in a minority of the modelled lakes. However, the reconstructions for the reference conditions are mostly very high. Our results indicate that a successful local diatom-total phosphorus model can be developed for an environmentally anomalous area. An important implication for lake restoration is that the reference conditions for the shallow, humic and eutrophic lakes in the Iisalmi region seem to be notably higher (up to 70 µgl -1 ) than the previously reported background total phosphorus concentrations for naturally eutrophic lakes in ; Vuori et al. 2006). Further research is under way to examine how well our local model reflects observations of total phosphorus in lake water, and whether it consistently shows larger variation than the previous regional model of Kauppila et al. (2002) for this lake type

Factors controlling recent diatom assemblages across a steep local nutrient gradient in central-eastern Finland

The Iisalmi Route, a chain of lakes in central-eastern Finland, is more eutrophic than its surroundings. We used multivariate analyses to study the influence of selected environmental factors (water quality, basin characteristics, and subcatchment surficial geology) on the recent diatom assemblages across this steep local nutrient gradient. In addition to the spatial analysis of surface sediment diatom assemblages from 51 sampling sites (48 lakes), temporal changes in the total phosphorus (TP) concentrations of one Iisalmi Route lake (Lake Kirmanjärvi) were analyzed using weighted averaging partial least squares regression and 27 fossil diatom samples. Both TP and electrical conductivity (EC) showed statistically significant independent signals in the modern diatom data. The TP gradient was related to till grain size variation suggesting that geological factors affect the spatial TP variation directly or indirectly through differences in land use. Based on the temporal study, the direct effect of geology is most likely behind the steep nutrient gradient in the area because Lake Kirmanjärvi was found to be naturally eutrophic. EC, on the other hand, seems related to anthropogenic disturbance. Our study highlights the importance of taking the local geology into account when assessing past or present water quality or planning for lake management.</p

Kaivannaisjätteen luokittelu pysyväksi – Louhinassa muodostuvat sivukivet

Kaivannaisjäte voidaan kaivannaisjäteasetuksen (379/2008) mukaisesti luokitella pysyväksi, kun kaivannaisjäte täyttää asetuksessa mainitut kriteerit. Oppaan tarkoituksena on auttaa kaivannaisalan toimijoita ja viranomaisia louhinnassa syntyvän kaivannaisjätteen luokittelussa pysyväksi. Oppaassa esitetään menettelyt kaivannaisteollisuudessa syntyvän sivukiven luokittelulle kaivannaisjäteasetuksen mukaisesti pysyväksi jokokansallisen pysyvien kivilajien luettelon tai tapauskohtaisen arvioinnin avulla

Electrochemical reactions of catechol, methylcatechol and dopamine at tetrahedral amorphous carbon (ta-C) thin film electrodes

The electrochemical reactions of dopamine, catechol and methylcatechol were investigated at tetrahedral amorphous carbon (ta-C) thin film electrodes. In order to better understand the reaction mechanisms of these molecules, cyclic voltammetry with varying scan rates was carried out at different pH values in H2SO4 and PBS solutions. The results were compared to the same redox reactions taking place at glassy carbon (GC) electrodes. All three catechols exhibited quasi-reversible behavior with sluggish electron transfer kinetics at the ta-C electrode. At neutral and alkaline pH, rapid coupled homogeneous reactions followed the oxidation of the catechols to the corresponding o-quinones and led to significant deterioration of the electrode response. At acidic pH, the extent of deterioration was considerably lower. All the redox reactions showed significantly faster electron transfer kinetics at the GC electrode and it was less susceptible toward surface passivation. An EC mechanism was observed for the oxidation of dopamine at both ta-C and GC electrodes and the formation of polydopamine was suspected to cause the passivation of the electrodes.Authors wish to acknowledge the financial support by the Finnish Parkinson Foundation (T.P.), the Finnish Funding Agency for Innovation (grant number 211488) (T.P., S.S. and T.L.), the Academy of Finland (grant number 285015) (T.L.) and MINECO project CTQ2013-44083-P (J.F.M.)

Opas kaivannaisjätteiden hallinnan MWEI BREF -vertailuasiakirjan parhaita käyttökelpoisia tekniikoita koskevien päätelmien soveltamiseen

Tässä oppaassa kuvataan kaivannaisjätteiden hallinnan sekä kaivannaisjätteistä aiheutuvien haitallisten vaikutusten ehkäisyn ja vähentämisen parhaat käyttökelpoiset tekniikat (BAT). Opas perustuu kaivannaisjätteiden hallinnan parhaita käyttökelpoisia tekniikoita koskevaan vertailuasiakirjaan "Best Available Techniques Reference Document for the Management of Waste from Extractive Industries” ja Suomen kansallisiin ohjeistuksiin, oppaisiin sekä lainsäädäntöön. Oppaassa käsitellään kaivannaisjätealueisiin liittyviä parhaita käyttökelpoisia tekniikoita läpi kaivannaisjätealueen elinkaaren. Oppaan yleiset BAT-päätelmät käsittelevät johtamista, tiedon keruuta ja hallintaa sekä kaivannaistoiminnan jätehierarkiaa. Riskiperusteiset BAT-päätelmät puolestaan kuvaavat tekniikoita, joilla ehkäistään ja vähennetään ympäristöön ja ihmisten terveyteen kohdistuvia vaikutuksia sekä tekniikoita, joilla varmistetaan kaivannaisjätteen sijoitusalueiden rakenteellinen vakavuus sekä kaivannaisjätteen fysikaalinen ja kemiallinen pysyvyys. Opas tukee vertailuasiakirjassa esitettyjen BAT-päätelmien soveltamista kaivannaisjätteiden hallinnassa ja sitä voidaan hyödyntää kaivannaisteollisuuden toiminnan suunnittelussa, toteuttamisessa sekä kehittämisessä

Ecosystem change in the large and shallow Lake Säkylän Pyhäjärvi, Finland, during the past ~400 years : implications for management

Lake Sakylan Pyhajarvi has been an important fishing site and drinking water source for the local population for centuries. The lake has undergone significant changes: (1) the water level was lowered in the 1600s and in the 1850s; (2) planktivorous coregonid fish were successfully introduced in the early 1900s; (3) nutrient input from intensified agriculture has increased since the 1950s and (4) the effects of the current variable climate on the lake and its catchment have become more evident since the 1990s. We determined the phases of oligotrophication, eutrophication and recovery and elucidated the ecosystem changes by combining palaeolimnological records with detailed neolimnological data. The sedimentary diatom and cladoceran assemblages first showed a relatively eutrophic period followed by oligotrophic periods, linked with the artificial changes in water level and consequent shifts in macrophyte abundance. The oligotrophic period in the early 1900s is thought to represent the target trophic state for the lake. After the 1950s, introduction of vendace resulted in higher planktivory reflected by an increased relative abundance of small-bodied pelagic cladocerans. Signs of eutrophication occurred due to increased nutrient load. During the last 10 years, signs of recovery have been recorded. A complex history such as that of Lake Pyhajarvi illustrates the difficulties in selecting management targets, and the risk of setting false targets, for lakes based solely on monitoring data-both neolimnological and palaeolimnological approach are needed.Peer reviewe

Geopolymers as active capping materials for in situ remediation of metal (loid)-contaminated lake sediments

Highlights • Geopolymers are novel active capping materials for contaminated sediments. • Metal(loid) bioavailability decreased compared to unamented sediment. • Slag-based geopolymer was more effective than metakaolin geopolymer or vermiculite. • The overall best material, alkali-activated slag, was suitable for Al, Cu, Fe and Ni. • Metakaolin geopolymer was suitable for Cu, Cr, and Fe and vermiculite for Al and Zn.Metal(loid) contamination in sediments is a widespread environmental issue. Sediments act normally as metal(loid) sinks, but if chemical conditions (such as pH or redox potential) change, they can become sources of secondary pollution. Consequently, various strategies for both in and ex situ remediation of contaminated sediments have been developed. One promising method is active capping, which involves the injection of adsorbents as a layer on the sediment surface or the mixing of adsorbents within the sediment. Adsorbents decrease the bioavailability of metal(loid)s. In the present work, the suitability of alkali-activated blast-furnace-slag, metakaolin geopolymer, and exfoliated vermiculite were evaluated for in situ stabilization of two metal(loid)-contaminated lake sediments through laboratory-scale experiments. The results indicated that adsorbent amendments had metal(loid)-specific performance: alkali-activated blast-furnace slag was suitable for Al, Cu, Fe, and Ni; metakaolin geopolymer for Cu, Cr (total), and Fe; and vermiculite for Al and Zn. None of the materials could stabilize Ba, Sr, or Ti. Furthermore, the amendments performed differently in two different lake sediments, implying that the effectiveness of the amendments needs to be confirmed on a case-by-case basis

Intressivertailu kaivoslain lupaprosessin osana

Tutkimusryhmä selvitti vesilain kaltaisen intressivertailun soveltuvuutta ja sisältöä kaivoslupaprosessin osana. Toimeksiannon mukainen tutkimus koski kaivoslain soveltamisalaa rajapintoineen. Kaivoslain uudistus on toimeksiannon mukaan erillinen hanke, joka ei liity tutkimuskysymyksiin. Tutkimuskysymyksinä työryhmä selvitti intressivertailun oikeudellisen sisällön, osatekijät, vertailutavat, vesilain kokemuksia, verrokkimaiden ratkaisuja ja muita tutkimuskysymyksiä, tavoitteena välttää päällekkäisyyksiä muun sääntelyn kanssa. Valtion turvallisuus ylittää muut intressit. Tutkimusryhmä pitää haasteellisena lakien keskinäisten soveltamis- ja hallinnonalarajojen päällekkäisyyksien vuoksi intressivertailun säätämistä kaivoslakiin. Kaivoslain intressivertailussa voisi ottaa huomioon kaivostoiminnan ympäristötekijöitä vain siltä osin kuin niistä ei säädetä muussa laissa. Lainsäätäjän arvioitavaksi jäävät intressivertailun säätämisestä kaivoslaissa seuraavat hyödyt ja haitat suhteessa julkisuudessa esitettyihin odotuksiin. Työryhmä selvitti lisäksi, millainen kestävän kehityksen taloudellisen, sosiaalisen ja ympäristöllisen pilarin, perustuslain ja kaivoslain kestävyyskriteerit täyttävä intressivertailu olisi, jos se nyt tai tulevaisuudessa otettaisiin käyttöön kaivoslain tai useampien lakien soveltamisaloilla. Julkaisu on läpikäynyt ulkopuolisen tieteellisen arvioinnin.Tämä julkaisu on toteutettu osana valtioneuvoston selvitys- ja tutkimussuunnitelman toimeenpanoa. (tietokayttoon.fi) Julkaisun sisällöstä vastaavat tiedon tuottajat, eikä tekstisisältö välttämättä edusta valtioneuvoston näkemystä