We discuss the background and methods for estimating uncertainty in a holistic manner in a regional terrestrial biota Full Carbon Account (FCA) using our experience in generating such an account for vast regions in northern Eurasia (at national and macroregional levels). For such an analysis, it is important to (1) provide a full account; (2) consider the relevance of a verified account, bearing in mind further transition to a certified account; (3) understand that any FCA is a fuzzy system; and (4) understand that a comprehensive assessment of uncertainties requires multiple harmonizing and combining of system constraints from results obtained by different methods. An important result of this analysis is the conclusion that only a relevant integration of inventory, process-based models, and measurements in situ generate sufficient prerequisites for a verified FCA. We show that the use of integrated methodology, at the current level of knowledge, and the system combination of available information, allow a verified FCA for large regions of the northern hemisphere to be made for current periods and for the recent past.

Many national exposure programmes have been performed in tropical and subtropical climates during the last 50 years. However, ambitious programmes involving more than a few countries are scarce. In this paper a recently formed network of test sites is described involving 12 test sites in Asia (India, Vietnam, Thailand, Malaysia and China including Hong Kong) and four test sites in Africa (South Africa, Zambia and Zimbabwe). This effort is part of the 2001-2004 Swedish International Development Agency (SIDA) funded Programme on Regional Air Pollution in Developing Countries (RAPIDC). Corrosion attack after one (2002-2003) year of exposure (carbon steel, zinc, copper, limestone and paint coated steel) are presented together with environmental data (SO₂, NO₂, HNO₃, O₃, particles, amount and pH of precipitation, temperature and relative humidity) for all the test sites. The obtained corrosion values are substantially higher than expected for limestone, higher than expected for carbon steel and lower than expected for zinc compared to values calculated using the best available dose-response functions.

In intensively cultivated areas, agriculture is a significant source of pesticides associated with storm runoff. When these pollutants enter aquatic receiving waters, they have potential to damage nearby aquatic ecosystems. Constructed wetlands are a best management practice (BMP) designed to help alleviate this potential problem. A constructed wetland system (180 x 30 m) comprised of a sediment retention basin and two treatment cells was used to determine fate and transport of a simulated storm runoff event containing the insecticide diazinon and suspended sediment. Wetland water, sediment, and plant samples were collected spatially and temporally over 55 d. Results indicated that 43% of the study's measured diazinon mass was associated with plant material, while 23 and 34% were measured in sediment and water, respectively. Mean diazinon concentrations in water, sediment, and plants for the 55-d study were 18.1 ± 4.5 μg/l, 26.0 ± 8.0 μg/kg, and 97.8 ± 10.7 μg/kg, respectively. Aqueous concentrations fluctuated in the wetlands between 51-86 μg/l for the first 4 h of the experiment; however, by 9 h, aqueous concentrations were approximately 16 μg/l. During the 55 d experiment, 0.3 m of rainfall contributed to fluctuations in diazinon concentrations. Results of this experiment can be used to model future design specifications for mitigation of diazinon and other pesticides.

Evaporation of trichloroethylene (TCE) is a viable option in the remediation of TCE contaminated water. In this study, laboratory batch experiments were conducted to understand the evaporation kinetics of TCE in surface water, with further extension of this knowledge to field application. Experiments were set up for 15, 30, 60, and 90 min time intervals in open glass containers with initial concentration of 10 mgl-¹ TCE in 100 ml water. The containers were either exposed to wind or were placed on an orbital shaker to produce constant water motion. A reference study carried out in absence of wind and water-motion showed much slower rate of TCE evaporation, compared to other studies done with wind or orbital shaker. Experiments with water turbulence at 150 rpm yielded a higher volatilization coefficient, Kv = 4.36 h-¹ for TCE. The wind at a flow rate of 0.7 m/s also gave rise to 2.24 h-¹ coefficient for TCE evaporation. The volatilization coefficient for the reference study yielded a smaller value of 0.23 h-¹, with corresponding half-life of 3 h, indicating the importance of wind and water motion in TCE evaporation. Experiments conducted at 150rpm and 0.7 m/s wind velocity showed consistent evaporation trend, and were in better agreement with the extrapolated rate of evaporation obtained through the first order rate equation.

Surface water is frequently contaminated by the trace metals, in particular lead and zinc, produced by mining activities. The infiltration of this water is likely to pollute surface soils and ground water. The study of the transfer of trace elements, especially lead, under real conditions is difficult to carry out due to the physicochemical and hydrodynamic complexity of real soil (preferential flows, conditions of unsaturation...), of the presence of colloids and of many candidate elements. The objective of the present study was to gain a better understanding of the parameters influencing the migration processes of trace elements in simplified systems; it was based on the study of Pb transfer in laboratory columns filled with soil. The results showed that retention of lead in soil is strongly dependent on feed flow rate, particulate bed tortuosity, bed height, water-soil surface contact and volume of water. Increase in bed height, water-soil surface contact and particulate bed tortuosity leads to higher contact time thus higher lead retention by soil, whereas increase in feed flow rate and volume of water leads to lower contact time thus lower lead retention by soil.

Investigation of nine herbaceous species collected around five polluters in northwestern Russia (nickel-copper smelters at Monchegorsk and Nikel, ore-roasting factory at Zapolyarnyy, aluminium smelter in Kandalaksha, and iron pellet plant at Kostomuksha) demonstrated that effects of pollution on plant growth were rarely significant in individual analyses. However, meta-analysis revealed decrease in plant size, in terms of height and leaf length; simultaneous increase in the number of leaves and flowers/inflorescences may compensate for this decline, thus the biomass of aboveground plant parts did not change. This result contrasts numerous experimental studies that generally demonstrate adverse effects of various pollutants on growth and reproduction of herbaceous plants, hinting that the effects detected in short-term experiments are of limited value for predicting performance of plant individuals surviving in polluted ecosystems. Changes in growth and reproduction of plants persisting under chronic pollution are minor presumably due to development of pollution tolerance and adaptation to altered environmental conditions.

In this study, benthic flux measurements of inorganic nitrogen (i.e., [graphic removed] , [graphic removed] + [graphic removed] ) were made using a batch incubation system at different stations (i.e., shallow sandy macrophyte and unvegetated beds, and deep central mud) over four seasons in Lake Illawarra, NSW, Australia, to study the influence of different primary producers (i.e., seagrasses, microphytobenthos (MPB) and macroalgae) and/or different sediment types (i.e., sand or mud) on the benthic fluxes. In general, nutrient fluxes displayed typical diel variations, with lower flux out of sediments (release) or enhanced uptake by the sediment in the light, due to the photosynthetic activities of the plant-MPB-sediment community in Lake Illawarra during photosynthetic periods. A distinct seasonal pattern of inorganic-N fluxes was also observed (e.g., the marked difference between summers 2002 and 2003). This may be explained by the seasonal variations in the biomass and activity (growing or decay phases) of MPB, seagrass and macroalgae, which may influence their nutrient assimilation and alter the chemical conditions of surface sediments that influence the benthic geochemical processes and thus benthic nutrient fluxes. On an annual basis, unvegetated sediments displayed net DIN effluxes, while seagrass beds showed a net DIN uptake, and the highest DIN uptakes coincided with the largest standing crop of seagrass and/or macroalgae and the highest levels of benthic community production. This may be due to the enhanced denitrification and/or assimilation activity by rooted plants and macroalgae, and the effect is most efficient during periods of net growth (e.g., in Spring 2002).

Sewage sludge is a cost-effective media for the production of Bacillus thuringiensis (Bt) based biopesticides. To enhance the entomotoxicity of the fermentation broth, pretreatments of sewage sludge by alkali and ultrasonic were applied in this study. Effects of alkaline and ultrasonic pretreatments on the soluble COD (SCOD) and total COD (TCOD) were evaluated by altering the alkali addition dose and the ultrasonic specific energy. Suitable pretreatment conditions were optimized with 5 g l-¹ sodium hydroxide (NaOH) for alkaline treatment and 1.2 x 10⁵ kJ kg-¹ of total solid for ultrasonic treatment. Fermentations of raw and pretreated sludge for biopesticides were carried out in a bench scale fermentor. Results revealed that both pretreatments were effective for Bt growth and metabolism. Higher viable cells (VC) and viable spores (VS) counts, δ-endotoxin yields and entomotoxicity were achieved in the pretreated sludge. The enhancement was attributed to more available nutrients and better oxygen transfer. Moreover, ultrasonic pretreated sludge was superior to alkaline pretreated sludge for δ-endotoxin production and entomotoxicity owing to its higher soluble C/N ratio and finer particles.

In 1998, the pond containing the ore wastes from a pyrite mine in Aznalcóllar (SW, Spain) broke open, spilling some 36×10⁵ m³ of acidic waters and 9 × 10⁵ m³ of tailings containing high concentrations of As and heavy metals. The affected area was around 55 km² of predominantly agricultural soils. After the clean-up of the tailings, many remediation actions were undertaken and the use of blocking agents to immobilize the As was one of the most extended measure. The first experiment performed was to determine the most important soil components in As adsorption under acidic conditions. A second experiment was conducted to neutralize the acidity caused by the solution coming from the tailings undergoing oxidation; an adequate liming material (sugar-refinery scum) was selected and the application rates were established. After the remediation measures, the zone was monitored for three years. A detailed study in four experimental plots located in the most polluted sector was carried out to test the influence of iron oxides in the As immobilization. The use of red soils of the area (rich in free-iron oxides Fed) was established as an appropriate material in the remediation of the area.

Heavy metal pollution in sediments derived from the Deûle canal and sampled at different sites not far from a smelting plant has been examined in the present work in order to identify the sources of these metals and to assess the sediment environmental quality. The total concentrations of lead, zinc, cadmium, thallium, indium and tin in the samples were determined using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Our investigations have revealed that metal pollution is readily apparent in the studied sediments, with metals contents largely exceeding those measured in the background soils: maximum values are obtained for sediments collected near the industrial zone. The chemical forms of Pb, Zn, Cd, Tl, In and Sn in these sediments have also been studied using a sequential extraction method in order to evaluate their possible mobility, bioavailability and toxicity in this aquatic environment. Overall, the averaged fractionation of Pb and Zn is dominated, in a decreasing order, by the easily reducible, oxidizable and carbonate fractions. The importance of oxidizable phase (which is assumed to be composed mainly of organic matter and sulphides) in the Pb and Zn fractionations has been confirmed by the detection of X-ray diffraction peaks ascribed to galena (PbS) and wurtzite (ZnS) in contaminated sediment samples. Anthropogenic Tl, In, and Cd are mainly retained in Fe–Mn oxides/hydroxides, whereas anthropogenic Sn predominates in aluminosilicates/clays. We suspect that elevated percentage levels of Pb, Zn, Cd and In in the reducible fraction constitute a particular potential risk to this aquatic environment in case early diagenetic phenomena (that are observed in the sedimentary material) and physical disturbances (that occur in the water column) both take place strongly in the medium.