Tree bark as a bioindicator of air pollution in Navarra,Spain

During a two year research period from 1992 to 1993, samples of different species of trees were taken in 17 forest stands located in Navarra, Spain. From these samples, bark extracts were prepared in which the pH and the conductivity were measured. The health of the sampling trees was also evaluated by determining the degree of defoliation and decoloration of the canopies. The bark tissue analysis revealed the presence of an environmental acidity gradient that decreased from NW to SE. This coincides with the location of important sources of pollution and their course of transport and dispersion. On the other hand, in the samples ofQuercus ilex a significant correlation between the pH and the defoliation levels (P≤0.01, r=0.62) was found. This fact reveals the potential usefulness of tree bark as a health bioindicator of trees.     

Acidity of tree bark as a bioindicator of forest pollution in Southern Poland

pH values and buffering capacity were determined for bark samples of five deciduous trees (oak, alder, hornbeam, ash, linden), one shrub (hazel) and one coniferous tree (scots pine) in the Cracow Industrial Region (Southern Poland) and, for comparison, in the Bia?owieza Forest (North-Eastern Poland). The correlation was found between acidification of tree bark and air pollution by SO₂ in these areas. All trees showed the least acidic reaction in the control area (Bia?owieza Forest), more acidic in Niepolomice Forest and the most acidic in the center of Cracow. The buffering capacity of the bark against alkali increased with increasing air pollution. The seasonal fluctuations of pH values and buffering capacity were found. Tree bark is recommended as a sensitive and simple indicator of air pollution.     

Coliforms,fecal coliforms,and fecal streptococci as indicators of water pollution

The presence and survival of coliforms, fecal coliforms, and fecal streptococci were studied in sewage treatment plants, heavily polluted rivers, a lake, and other drinking water sources. In all cases the fecal streptococci were generally more resistant to the natural water environment and to purification processes than the other indicator organisms and, at points distant from the original source of pollution were often the only indicators of the fecal nature of the pollution. In two of the systems studied the survival of the fecal streptococci paralleled the survival of enteric viruses better than the coliforms. The fecal streptococci may thus in certain cases provide a better estimate of the probable virus content in lightly contaminated water than the other two indicators.     

Broth from canned clams is suitable for use as an excellent source of free vitamin B12

Vitamin B(12) was assayed and characterized in the broth of canned clams (boiled plain). The broth contained considerable amounts of vitamin B(12) (2.7-14.1 μg/100 g, 1.3-6.7 μg/can). HPLC and LC/ESI-MS/MS chromatograms demonstrated that the clam broth contained true vitamin B(12). Gel filtration experiments indicated that most (72%) of the vitamin B(12) found in the broth was recovered in free vitamin B(12) fractions. These results indicate that the clam broth would be suitable for use an excellent source of free vitamin B(12) for elderly persons with food-bound vitamin B(12) malabsorption.     

Environmental fecal pollution and concentration power of the clam Chamelea gallina

This study is aimed to verify hygienic conditions of a commercially-important clam: Chamelea (Venus) gallina, widely distributed along the Italian coasts. Five mussel beds have been simultaneously surveyed, collecting samples of water, sediment and molluscs. Total coliforms, fecal coliforms, and fecal streptococci have been analyzed. Results show that this shellfish does not seem to accumulate enteric bacteria in spite of the microbial contamination of water and sediment.     

沼气工程对畜禽粪便污染环境成本的控制效果

沼气工程是治理畜禽粪便污染的主要方法,可提供清洁能源,减少温室气体排放,减轻环境污染,具有良好的环境效益。本研究以湖南省洞庭湖区为例,利用《气候变化框架公约》清洁机制执行理事会批准的方法(ACM0010)和环境成本估算方法,分析了沼气工程对畜禽粪便污染的环境成本的控制潜力。结果表明,在湖南省洞庭湖区的畜禽粪便均采用沼气项目进行污染治理条件下,年出栏5 000头以上的生猪规模养殖场均进行沼气发电,其他畜禽养殖场的沼气全部用于畜禽养殖场及周边居民的供热和照明使用,则2006年可减排温室气体2 891 614 t CO2当量,减少温室气体排放环境成本为4.52亿元;同时,可减排水体污染、土壤污染、微生物污染控制的环境成本分别为4.56亿元、1.69亿元、5.32亿元。因此,要支持和鼓励养殖户利用沼气工程处理畜禽粪便,实现畜禽粪便污染治理环境效益、经济效益和社会效益的有机统一。     

The use of microbial parameters in monitoring soil pollution by heavy metals

Microbial parameters appear very useful in monitoring soil pollution by heavy metals, but no single microbial parameter can be used universally. Microbial activities such as respiration, C and N mineralization, biological N₂ fixation, and some soil enzymes can be measured, as can the total soil microbial biomass. Combining microbial activity and population measurements (e.g., biomass specific respiration) appears to provide more sensitive indications of soil pollution by heavy metals than either activity or population measurements alone. Parameters that have some form of internal control, e.g., biomass as a percentage of soil organic matter, are also advantageous. By using such approaches it might be possible to determine whether the natural ecosystem is being altered by pollutants without recource to expensive and long-running field experiments. However, more data are needed before this will be possible. Finally, new applications of molecular biology to soil pollution studies (e.g., genetic fingerprinting) which may also have value in the future are considered.     

Distribution of copper smelter emissions in Southeastern Arizona — Using honey mesquite as a bioindicator

Honey mesquite (Prosopis juliflora), a representative species of the Sonoran Desert ecosystem, was studied as a possible bioindicator for industrial smelter pollution. Samples from soils, leaves and bark were collected along distance and elevation gradients from the largest operating copper smelter in Arizona and analyzed for element concentrations of Zn, Cu, Fe, Ti, Mn, Al, Mg, Cs, Sm, Ce, U, Th, Yb, As, La, Hf, Sb, Sc, V, In, W, Ba, Br, K, Na, Cl and Au. Depending on the sample type — soil, leaf or bark — between 5 and 15 elements were identified as smelter immissions. Two distinct covariate element groups formed in samples from the study site could be related to the chemistry of different smelting processes. A common atmospheric transport pattern was found to exist for the smelter emittants Cu, Sb and As over long distances. The identification and specification of smelter immissions in honey mesquite makes this tree a well-suited bioindicator for industrial smelter pollution.     

1-Hydroxypyrene in milk and urine as a bioindicator of polycyclic aromatic hydrocarbon exposure of ruminants

Urinary 1-hydroxypyrene (1-OH-pyrene) is now largely considered to be a valuable biomarker of exposure of man and animals to pyrene and other polycyclic aromatic hydrocarbons (PAHs). However, from a practical and agronomic standpoint, the question remains whether such biomarking capability still holds when 1-OH-pyrene is analyzed in milk produced by ruminants. To assess this hypothesis, four goats were daily submitted to three different amounts of pyrene oral ingestion, together with phenanthrene and benzo(a)pyrene (1, 7, and 49 mg/day during 1 week each). An HPLC-fluorometric analysis of 1-OH-pyrene in milk revealed a perfect correlation between pyrene doses and 1-OH-pyrene detected in milk, thus fully confirming the biomarking capability of 1-OH-pyrene and providing information on its transfer coefficient toward milk. Transfer equations such as the ones found in the present study could be used as a valuable and practical risk assessment tool in (i) the accurate monitoring of exposure of ruminants to pyrene and (ii) the evaluation of occupational and environmental exposure of ruminants to PAH mixtures.     

Evaluation of black spruce (Picea mariana) as a bioindicator of aluminum contamination

The aim of this work is to evaluate black spruce (Picea mariana) as an indicator of environmental aluminum contamination. The territory studied extends to a radius of 100 km around the Alcan aluminum refinery in Jonquiere, Quebec, Canada. Samples of wood were taken from the trunks of trees at 26 sites at distances of 5, 10, 20, 30, 40, 50 and 100 km from the refinery. Five trees were sampled at each site. Each sample was cut into 25 pieces corresponding to 50 yr growth. These were analyzed for aluminum by neutron activation. Soil samples taken near the bases of the trees were also analyzed and significant variations in exchangeable aluminum were observed as a function of direction from the refinery and distance. The pH of organic and mineral horizons show no significant difference. Exchangeable aluminum increased with soil acidity. The most contaminated sites showed important correlations (r²=0.73) between exchangeable aluminum in soil and aluminum in bark. We observed greater aluminum concentrations in tree rings corresponding to the last 20 yr, especially at sites directly exposed to environmental contamination along prevailing winds. In conclusion, black spruce appears to be a better spatial than chronological indicator of aluminum contamination.     

Extreme variability of steroid profiles in cow feces and pig slurries at the regional scale: implications for the use of steroids to specify fecal pollution sources in waters

Thirty-five samples of cow feces (cowpat and cow manure) and pig slurries subjected to different treatment processes and different storage times before land spreading were extracted and analyzed by gas chromatography-mass spectrometry to determine their fecal stanol profiles. The fresh pig slurry data presented here increase considerably the classical range of values obtained for steroid ratios, resulting in an overlap with the range for cow feces. These results lead to the inability to distinguish species source of feces on the basis of steroid ratios alone. The cause of these differences is not known, although it appears likely to be related to differences in the metabolism of animals in relation to their age and/or variations in diet, rather than to secondary mechanisms of steroid degradation during storage or/and treatment of the feces. Nevertheless, the specificity of steroids to serve as a tool to differentiate cow feces from pig slurries is restored by considering the fecal stanol profile, notably, the six most diagnostic stanol compounds, which are 5β-cholestan-3β-ol (coprostanol), 5β-cholestan-3α-ol (epicoprostanol), 24-methyl-5α-cholestan-3β-ol (campestanol), 24-ethyl-5α-cholestan-3β-ol (sitostanol), 24-ethyl-5β-cholestan-3β-ol (24-ethylcoprostanol), and 24-ethyl-5β-cholestan-3α-ol (24-ethylepicoprostanol). In this study, chemometric analysis of the fingerprint of these six stanols using principal components analysis (PCA) distinguished pig slurries from cow feces. The application of PCA to the stanol profiles, as developed in this study, could be a promising tool for identifying the animal source in fecal contamination of waters.     

Soil microbial community as bioindicator of the recovery of soil functioning derived from metal phytoextraction with sorghum

A three-month microcosm study was carried out in order to evaluate: (i) the capacity of sorghum plants to phytoextract Cd (50 mg kg⁻¹) and Zn (1000 mg kg⁻¹) from artificially polluted soil and (ii) the possibility of biomonitoring the efficiency of phytoremediation using parameters related to the size, activity and functional diversity of the soil microbial community. Apart from plant and soil (total and bioavailable) metal concentrations, the following parameters were determined: soil physicochemical properties (pH, OM content, electrical conductivity, total N, and extractable P and K), dehydrogenase activity, basal- and substrate-induced respiration (with glucose and a model rhizodeposit solution, both adjusted to 800 mg C kg⁻¹ DW soil and 45.2 mg N kg⁻¹ DW soil), microbial respiration quotient, functional diversity through community level physiological profiles and, finally, seed germination toxicity tests with Lepidium sativum. Sorghum plants were highly tolerant to metal pollution and capable of reaching high biomass values in the presence of metals. In the first two harvests, values of shoot Cd concentrations were higher than 100 mg Cd kg⁻¹ DW, the threshold value for hyperaccumulators. Nonetheless, in the third harvest, the bioconcentration factor was 1.34 and 0.35 for Cd and Zn, respectively, well below the threshold value of 10 considered for a phytoextraction process to be feasible. In general, microbial parameters showed lower values in metal polluted than in control non-polluted soils, and higher values in planted than in control unplanted pots. As a result of the phytoextraction process, which includes both plant growth and metal phytoextraction, the functioning of the phytoremediated soil, as reflected by the values of the different microbial parameters here determined, was restored. Most importantly, although the phytoextracted soil recovered its function, it was still more phytotoxic than the control non-polluted soil.     

The use of algae-cyanobacterial communities for the assessment of lead pollution of gray forest soils

The effect of lead acetate on the characteristics of the algae-cyanobacterial communities of a gray forest soil was studied in a model experiment. The investigation was carried out using the method of water-soil cultures. The advantages and disadvantages of the application of this method for the ecotoxicological experiments are considered. The species of cyanobacteria and algae tolerant and sensitive to heavy metals were revealed. The addition of lead acetate at doses of 750 and 1500 mg/kg to soil caused a decrease in the species diversity and abundance of the cyanobacteria and algae, a reduction of the total content of chlorophyll, and changes in the morphology of individuals, whereas a dose of 300 mg/kg stimulated the development of the algae-cyanobacterial communities. The effect observed is suggested to be due to the double action of the salt: the adverse influence of the lead cations, and the positive influence of the acetate anions and the protective function of the soil. The use of a complex of different parameters of the biological organization of the communities at the cell, organism, and community levels results in the objective and complete assessment of the toxicant effects on the algae-cyanobacterial community of the gray forest soil.     

Cuticular features as indicators of environmental pollution

Several leaf cuticular features such as stomatal frequency, stomatal size, trichome length, type, and frequency, and subsidiary cell complex respond to environmental pollution in different ways and hence can be used as indicators of environmental pollution in an area. Several modifications in cuticular features under polluted environments seem to indicate ecotypic or survival significance for the plant species under investigation.     

The use of natural strontium isotopes as tracers in environmental studies

Naturally occurring isotopes of elements like strontium have proved to be good tools for tracing the past and for monitoring of processes in the present. The spread and variation in⁸⁷Sr/⁸⁶Sr ratios make Sr isotopes a powerful tool when it comes to detecting trends in the soil-vegetation system. There is also a great potential in combining different parameters like soil, water, biological material and isotopes for detecting environmental changes over short as well as long time periods. Sampling of the past is a difficult task but biological material, in combination with inorganic material, proves advantageous as environmental archives. There is also the possibility of using museum collections as environmental historic archives. This paper discusses the potential of using the natural⁸⁷Sr/⁸⁶Sr ratio as a tracer for environmental studies. The results presented point to an ongoing impoverishment of the environment and show that the temporal trend in Sr isotope composition for different media is similar despite material and location of test area.     

Conservation and cultivation of giant clams in the tropical Pacific

Giant clams (Tridacnidae) are slow-growing and long-lived animals on the coral reefs of the Indo-West Pacific faunal region. There is a peak period, either summer or winter, in breeding activity of four giant clam species studied. Fertilised eggs develop into planktotrophic veliger larvae which settle and metamorphose into benthic juveniles about ten days after spawning. Although short pelagic larval life favours cultivation of the clams, spat handling is difficult because of the small size in postmetamorphosis juveniles of about 0.2 mm shell length. Colonising and maintenance strategies of giant clam populations resemble those of forest trees, indicating that giant clam resource management might parallel that of forestry.     

Energy use,emissions, and air pollution reduction strategies in Asia

In contrast to Europe and North America, air pollution in Asia is increasing rapidly, resulting in both local air quality problems and higher acidic depositions. In 1989, an east-west group of scientists initiated a multi-institutional research project on Acid Rain and Emissions Reduction in Asia, funded for the past two years by the World Bank and the Asian Development Bank. Phase I, covering 23 countries of Asia, focussed on the development of PC-based software called the Regional Air Pollution INformation and Simulation Model (RAINS-ASIA). A 94-region Regional Energy Scenario Generator was developed to create alternative energy/emission scenarios through the year 2020. A long-range atmospheric transport model was developed to calculate dispersion and deposition of sulfur, based upon emissions from area and large point sources, on a one-degree grid of Asia. The resulting impacts of acidic deposition on a variety of vegetation types were analyzed using the critical loads approach to test different emissions management strategies, including both energy conservation measures and sulfur abatement technologies.     

Vanadium and nickel in dustfall as indicators of power plant pollution

The elements V and Ni were determined in dustfall (settling particles), airborne dust and in soils at various points in the greater Tel-Aviv area between the years 1973 and 1984. Good correlations were found between measured distribution patterns for V and Ni in dustfall during the summer months and those predicted for settling particles from the Tel-Aviv power station (which burns heavy fuel oil) using a meteorological model based on diffusion from an elevated point source. The distribution patterns for V and Ni in dustfall collected in the Tel-Aviv area were very similar to those previously measured for SO₂ and total S compounds. The concentration of V and Ni in soils also conforms to a pattern that points to the power station as a major source of these metals. It is suggested that V and Ni may be used as tracers for measuring the distribution of pollution from oil fired power stations.     

Mosses as bioindicators of heavy metal pollution in polish national parks

The concentrations of heavy metals (Cd, Co, Cr, Ni, Cu, Ph, Zn, Mn, Fe) and other elements (Mg, Na, K, Ca) were determined in the samples of Pleurozium schreberi and Hylocomium splendens from 12 Polish national parks. The significant differences in the concentrations of all heavy metals between particular parks were found. The lowest concentrations of these metals were recorded in the mosses from the national parks in northern Poland, the highest in southern Poland. Significant differences in the heavy metals contents of the mosses between central and peripheral park areas, between green and brown parts of mosses, as well as between moss species were also found.     

The use of carbonatite rock powder as a liming agent

Carbonatite rock powder, originating from the Lillebukt Alkaline Complex at Stjernøy in northern Norway, can potentially be used as a slow‐releasing lime and potassium (K) and magnesium (Mg) fertilizer due to a high concentration of the easily weathered minerals calcite (42%) and biotite (30%). However, the enrichment of barium (Ba) and strontium (Sr) may cause an undesired uptake to plants when carbonatite is applied to agroecosystems. A pot experiment was designed to investigate the liming and fertilization effects of carbonatite and the potential mobilization of Ba and Sr compared to a dolomite lime commonly used in Norwegian agriculture. These liming agents were mixed with a sandy soil applied to different amounts of peat, and the uptake of Ba, Sr, calcium (Ca), Mg, and K by Festuca arundinácea Schreb. Kora (tall fescue) and Trifolium repens L. Milkanova (white clover) was evaluated. The liming agents were generally incapable of buffering the acidifying effect from increased applications of peat, while the plant dry mass was unaffected. Compared to pots given dolomite and soluble K, the availability of K from carbonatite to plants was equally high or higher, and no difference in the K:(Ca + Mg) ratio in plants was observed. Carbonatite was a significant source to plant Ba and Sr, and the uptake seemed to follow the Ca uptake. Addition of peat amplified the uptake of Ba, Sr, Ca, Mg, and K to plants, probably an effect of organic acid‐induced weathering of carbonatite. White clover took up Ba, Sr, and Ca more effectively than tall fescue, but the Ba and Sr concentrations in plants were relatively moderate compared to concentrations reported from field investigations.