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1.
Hannu Marttila Annalea Lohila Pertti Ala-Aho Kashif Noor Jeffrey M. Welker Danny Croghan Kaisa Mustonen Leo-Juhani Meriö Anna Autio Filip Muhic Hannah Bailey Mika Aurela Jussi Vuorenmaa Timo Penttilä Valtteri Hyöky Eric Klein Anton Kuzmin Pasi Korpelainen Timo Kumpula Anssi Rauhala Bjørn Kløve 《水文研究》2021,35(9):e14350
Subarctic ecohydrological processes are changing rapidly, but detailed and integrated ecohydrological investigations are not as widespread as necessary. We introduce an integrated research catchment site (Pallas) for atmosphere, ecosystems, and ecohydrology studies in subarctic conditions in Finland that can be used for a new set of comparative catchment investigations. The Pallas site provides unique observational data and high-intensity field measurement datasets over long periods. The infrastructure for atmosphere- to landscape-scale research in ecosystem processes in a subarctic landscape has recently been complemented with detailed ecohydrological measurements. We identify three dominant processes in subarctic ecohydrology: (a) strong seasonality drives ecohydrological regimes, (b) limited dynamic storage causes rapid stream response to water inputs (snowmelt and intensive storms), and (c) hydrological state of the system regulates catchment-scale dissolved carbon dynamics and greenhouse (GHG) fluxes. Surface water and groundwater interactions play an important role in regulating catchment-scale carbon balances and ecosystem respiration within subarctic peatlands, particularly their spatial variability in the landscape. Based on our observations from Pallas, we highlight key research gaps in subarctic ecohydrology and propose several ways forward. We also demonstrate that the Pallas catchment meets the need for sustaining and pushing the boundaries of critical long-term integrated ecohydrological research in high-latitude environments. 相似文献
2.
During the manufacturing of chromate salts (1972–1992) large quantities of Chromite Ore Processing Residue (COPR) were released
into a decantation pond east of the former chemical plant of Porto-Romano (Durres, Albania), giving rise to yellow colored
pond sediments. These Cr(VI) bearing sediments were deposited upon Quaternary silty-clay lagoonal sediments rich in iron oxides
and organic matter. The pH values in these lagoonal sediments vary around 6.6, while in the pond sediments, it is mainly acidic
(due to the presence of the sulfur stock piles in the area and the release of the H2SO4 from the activity of the former chemical plant), varying between 1.4 and 3.8. Continuous leaching of the COPR waste resulted
in yellow-colored surface water runoff. The prediction of pH changes in the different types of sediments based upon acid/base
neutralizing capacity (ANC/BNC) jointly with the quantitative data on release of heavy metals and especially Cr is considered
an important advantage of the pHstat leaching test if compared to conventional leaching procedures. Thus, factors controlling the leaching of Cr(VI), Cr(III),
Ca, Al, Fe, Mg from the COPR were investigated by means of pHstat batch leaching tests and mineralogical analysis. Moreover, mathematical and geochemical modeling complemented the study.
The COPR in the area contain very high concentrations of chromium 24,409 mg/kg, which mainly occurs as Cr(III) (75–90%) as
well as Cr(VI) (25–10%). The leaching of Cr(VI) occurs in all the range (2–10) of the tested pH values, however, it decreases
under acidic conditions. Beside some reduction of Cr(VI) to Cr(III), the Cr(VI) content of the leachtes remains relatively
high in the acidic environment, while the limning of Cr(VI) pond sediments will increase the release of the latter specie.
The leaching of the Cr(III) occurs strictly under acidic conditions, whereby limning of these sediments will give rise to
the lower solubility of Cr(III). The key mineral phases responsible for the fast release of the Cr(VI) are: the chromate salts
(i.e. sodium chromate and sodium dichromate), while sparingly soluble chromatite (CaCrO4) and hashemite (BaCrO4) release Cr(VI) very slowly. Thus, pH and mineral solubility have been identified as key factors in the retention and the
release of the hexavalent CrO4
2− and Cr2O7
− from the COPR-rich pond sediments. 相似文献
3.
Annual methane emission from Finnish mires estimated from eddy covariance campaign measurements 总被引：4，自引：0，他引：4
K. J. Hargreaves D. Fowler C. E. R. Pitcairn M. Aurela 《Theoretical and Applied Climatology》2001,70(1-4):203-213
Summary Measurements of landscape-scale methane emission were made over an aapa mire near Kaamanen in Finnish Lapland (69° 8′ N,
27° 16′ E, 155 m ASL). Emissions were measured during the spring thaw, in summer and in autumn. No effect of water table position
on CH4 emission was found as the water table remained at or above the surface of the peat. Methane emission fluxes increased with
surface temperature from which an activation energy of −99 kJ mol−1 was obtained. Annual emission from the site, modelled from temperature regression and short-term flux measurements made in
three separate years, was calculated to be 5.5 ± 0.4 g CH4 m−2 y−1 of which 0.6 ± 0.1 g CH4 m−2 y−1 (11%) was released during the spring thaw which lasted 20 to 30 days.
The effect of global warming on the CH4 budget of the site was estimated using the central scenario of the SILMU (Finnish Research Programme on Climate Change) model
which predicts annual mean temperature increases of 1.2, 2.4 and 4.4 °C in 2020, 2050 and 2100, respectively. Maximum enhancements
in CH4 emission due to warming were calculated to be 18, 40 and 84% for 2020, 2050 and 2100, respectively. Actual increases may
be smaller because prediction of changes in water table are highly uncertain.
Received September 17, 1999 Revised October 16, 2000 相似文献
4.
Near the outskirts of the Albanian port of Durres on the Adriatic Coast, at a place called Porto Romano, an old chemical complex
has been producing chromate salts for a period of ∼20 years (1972–1993). As a result large quantities of chromite ore processing
residue (COPR) waste were released mainly as suspended particles and/or dissolved species in effluents, which settled in a
decantation pond area, 200 × 250 m in size, east of the industrial plant. Unfortunately, pollutants were spread out with time.
Knowing that chromium mobility and toxicity in natural settings is species dependent, the species characterization has been
carried out in different sampling media (pond sediments, lagoonal sediments and water samples). Five pond profiles were sampled
within the decantation area up to a depth of ∼1 m, till the underlying Quaternary lagoonal silty-clays were reached. Total
Cr content is highly variable with values between 1,130 and 24,409 mg/kg which is clearly higher than the defined local background
values for lagoonal silty-clays (198 mg/kg of Cr). Leaching of Cr(VI) especially occurs in the pond sediments, which are low
in OC, CEC and clay content, under acidic and neutral pH conditions (e.g. up to ∼2,230 mg/kg Cr(VI) leached from a sample
containing a total concentration of Cr 12,200 mg/kg). Moreover, leaching of the Cr(III) occurs only under strictly acidic
conditions (maximum 1,144 mg/kg leached from a sample containing a total Cr-concentration of 17,608 mg/kg). In this study
also a number of natural attenuation conditions (i.e. reaction with lagoonal clays rich in organic matter and iron as well
as isomorphous substitution) have been recognized. 相似文献
5.
The degree of contamination in soils, sediments and dusts can be assessed based on knowledge of a variety of factors, such as industrialization, type of contaminants, deposition conditions, contamination-control techniques, along with the characteristics of the recipient environmental compartments, which include pathways for contamination transport, depth of infiltration, and degree of groundwater contamination. The impact of contaminants also depends on the quantity, mobility and speciation of contaminants/wastes as well as on the sensitivity of the recipient compartments. With sufficient knowledge of these factors, a number of conclusions can be drawn concerning the status of contamination in industrialized areas. This literature review aims to scrutinize some of the methods used to analyse the occurrence, speciation, mobility, bioavailability and likely the toxic effects of contaminants in the environment. 相似文献
6.
Aurela Shtiza Artan Tashko Rudy Swennen Adelheit Van den Brande 《Central European Journal of Geosciences》2009,1(1):63-83
An investigation of the metallurgical complex surroundings in Elbasani, Albania used background samples to rule out the level of contamination in the study area. Our results show that atmospheric dust particles and soils are of high concern while overbank sediments and actual river sediments are of lower concern. The heavy metals with concentrations of up to 5 times above the local background values are Zn, Cr, Ni, Cu, Fe and Co in soils; Fe, Cr, Co, Ni, Zn, Pb in dust particles; and, Cr and Zn in the actual river/stream sediments. Due to the small size of the dust particles and the atmospheric transportation mechanism primarily related to prevailing winds, the concern for the transport of dust particles is high, especially with respect to risks associated with inhalation. The people working and living in the vicinity of the metallurgical complex of Elbasani are at the highest risk of exposure. Concerns relating to soils are associated with the potential for translocation of the trace element particles into vegetation, in particular, within the upper part of the plants. Therefore, the consumption of the vegetables grown in the vicinity of the metallurgical site should be avoided. Special attention has been given to the Shkumbini river, where the long residence time of water and particulates may result in transitions of trace elements between dissolved and particulate phases downstream. 相似文献
7.
This paper presents the results of a literature review on the conceptual model of a sampling design and the different types of samples that can be used to characterize the nature and the extent of contamination at a specific site. The main findings stress the importance of sampling for obtaining relevant sample types and subsequent-qualitative results. The proposed sampling design can be used for environmental studies where, the efficient use of time, money, and human resources are very critical. A good quality sampling design should meet the needs of the study with a minimum expenditure of resources. 相似文献
8.
Chromium and nickel distribution in soils, active river, overbank sediments and dust around the Burrel chromium smelter (Albania) 总被引：2，自引：0，他引：2
Chromium ore was treated to produce ferrochromium from 1979 until 2000 in a smelter in Burrel, 35 km NE of Tirana (Albania). As a consequence, large amounts of solid waste, i.e. slags (about 9.106 m3) have been disposed next to the smelter, disfiguring the landscape. In an attempt to define contaminated sites, heavy metal content of the different sampling media have been compared with respective background samples.In the study area, the determination of background values in soil samples is complicated due to the different geological substrates. Cr and Ni background concentrations in serpentinite-derived soils, west of the smelting plant, are markedly higher than in the Pliocene gravel/sandy soils, where the smelter is situated (Cr 2147 and 193 mg/kg, respectively; Ni 2356 and 264 mg/kg). These values are clearly lower than those encountered around the smelter. Average total Cr and Ni concentrations in soils around the smelter are 3117 and 1243 mg/kg, respectively. The highest concentrations of Cr (up to 2.3 wt.%), were recorded in samples taken near the smelting compartment within the industrial plant and next to the slags clearly indicating that the smelter forms a point source of Cr contamination. The Cr / Fe ratio is the best indicator to differentiate non-polluted (Cr / Fe Serpentinite soil: 130–390; Pliocene soils: < 130) from polluted areas (> 390 smelting nearby of the slags).Cr and Ni values for local backgrounds in stream and overbank sediments were taken in the Mat river 6 km upstream and to the east of the smelter (268 and 430 mg/kg for Cr, and 306 and 604 mg/kg for Ni, respectively). Equivalent sediments taken from the Zalli i Germanit river, which drains the smelter area are respectively 816 and 1126 mg/kg for Cr and 1115 and 1185 mg/kg for Ni.Dust samples, taken from the lofts of houses up to 2 km from the smelter, display high concentrations of Cr, Ni and Zn (average contents of 2899, 436 and 902 mg/kg, respectively). The later concentrations in the dust samples have been confirmed by mineralogical analysis where Cr-bearing mineral phases such as ferrochromium and chromium oxides, clearly relate to the activity of the smelter. Consequently, atmospheric deposition of dust particles forms a serious problem and can also be responsible for the elevated contents encountered in soil samples around the smelter.All these data show that the degree of contamination caused by industrial activity of the Burrel Cr-smelter is severe, although no Cr(VI) was detected in soil water extractions nor in the surface or groundwater where concentrations were < 0.01 mg/kg. 相似文献
9.
C. R. Lloyd R. J. Harding T. Friborg M. Aurela 《Theoretical and Applied Climatology》2001,70(1-4):19-33
Summary Measurements of the surface fluxes of heat and water vapour were taken at four sites across the European Arctic as part of
the EU funded LAPP project. The sites cover a range of latitudinal, altitudinal and climatic conditions. The most northerly
site is near Ny-?lesund, Svalbard, a polar semi-desert with continuous permafrost. A second permafrost site is a fen area
in the Zackenberg valley, East Greenland. Finally two sites in northern Finland, Skalluvaara and Kaamanen are on the southern
boundary of the region affected by permafrost. At all sites measurements were made of the turbulent fluxes of heat and water
vapour using eddy correlation equipment for at least one active season.
The net radiation totals for July and August are similar at all sites. At the sites with permafrost a substantial proportion
(over 20%) of the net radiation goes into soil heat flux, to thaw the soil moisture in the top metre. Of the remaining energy
just over half is used for evaporation. At the Finnish sites the vegetation is largely deciduous and this is seen in the record
with higher evaporative ratios in July and August, after the vegetation becomes green. The Finnish sites tend to have higher
surface resistance to evaporation; however, the evaporative demand is greater leading to slightly higher evaporation rates.
The two Finnish sites have a similar seasonal pattern determined by the water table and seasonality of the vegetation. The
two northern sites show a pattern that is determined primarily by the variation of water table only. It is concluded that
the water balance through the active season is influenced primarily by the history of snow cover. The seasonality of the vegetation,
the permafrost and the depth of water table are also important influences.
Received November 1, 1999 Revised April 17, 2000 相似文献
10.
Summary Net ecosystem CO2 exchange was measured over a mountain birch forest in northern Finland throughout the growing season. The maximal net CO2 uptake rate of about − 0.5 mg(CO2) m−2 s−1 was observed at the end of July. The highest nocturnal respiration rates in early August were 0.2 mg(CO2) m−2 s−1. The daily CO2 balances during the time of maximal photosynthesis were about −15 g(CO2) m−2 d−1. The mountain birch forest acted as a net sink of CO2 from 30 June to 28 August. During that period the net CO2 balance was −448 g(CO2)m−2. The interannual representativeness of the observed balances was studied using a simplified daily balance model, with daily
mean global radiation and air temperature as the input parameters. The year-to-year variation in the phenological development
was parameterised as a function of the cumulative effective temperature sum. The daily balance model was used for estimating
the variability in the seasonal CO2 balances due to the timing of spring and meteorological factors. The sink term of CO2 in 1996 was lower than the 15-year mean, mainly due to the relatively late emergence of the leaves.
Received October 11, 1999 Revised April 25, 2000 相似文献