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1.
The impact of SO2 dry deposition from mining emissions on cricket abundance, diversity and composition was investigated at Mount Isa in the semiarid tropics of northern Australia. Seventy-one sites were sampled, stratified at two levels: sulphur deposition zones (high, medium, low, and background zones) and habitat (rocky ridge, rocky plain and alluvial plain). The three habitats did not support distinctly different cricket assemblages. Crickets responded to SO2 emissions, but impacts were largely restricted to the high-sulphur zone. Generalised linear modelling showed significant reductions in the probability of presence in the high-sulphur zone for the three genera Eurepella, Salmanites and Endacusta , and the subfamily Eneopterinae. In ordination space, the three high-sulphur zone by habitat combinations were clearly separated from all other combinations, and vector fitting of environmental variables showed soil SO4 to be a primary correlative factor of this separation. Crickets are sensitive to SO2 emissions and they appear to be a good indicator group in this context.  相似文献   

2.
Abstract. The effect of short-term SO2 fumigation on photosynthesis and transpiration of Vicia faba L. was measured at different irradiances and SO2 concentrations. At high irradiances photosynthetic rates were reduced when leaves were exposed to SO2 and the magnitude of the reduction was linearly related to the rate of SO2 uptake through the stomata. Photosynthetic rates stabilized within 2 h after the start of fumigation.
The effect of SO2 on photosynthesis was measured at different CO2 concentrations to analyse the contribution of stomatal and non-stomatal factors to photosynthetic inhibition. Mesophyll resistance to CO2 diffusion increased as a result of SO2 exposure and caused a rapid reduction in photosynthesis after the start of fumigation. Stomatal resistance was not affected directly by SO2 fumigation, but indirectly as a result of a feedback loop between net photosynthesis and internal CO2 concentration.
Analysis of gas-exchange measurements in biochemical terms indicated that photosynthetic inhibition during SO2 exposure can be explained by a stronger reduction in the affinity of RBP carboxylase/oxygenase for CO2 than for O2.  相似文献   

3.
The dose- and time-response effects of 3 days of 6 h day-time sequential exposures to NO2, SO2 and SO2+NO2 of 0.45–1.81 μl l−1 (ppm) SO2 and 1.50–7.65 μl l−1 NO2 on photosynthesis, transpiration and dark respiration were examined for nine Carpatho-Ukrainian half-sib families and a population from the GFR ('Westerhof') of Norway spruce [ Piecea abies (L.) Karst.], all in their 5th growing season.
SO2+NO2 inhibited photosynthesis and transpiration and stimulated dark respiration more than SO2 alone. SO2 and SO2+NO2 at the lowest concentrations inhibited night transpiration, but increased it at the highest concentration, the strongest effects being obtained with combined exposures. Photosynthesis of the different half-sib families was affected significantly differently by SO2+NO2 exposures. NO2 alone had no effects.
Sensitivity to transpiration decline correlated negatively with branch density. Height of trees correlated postitively with decline sensitivity in the seed orchard. The distribution of photosynthesis and transpiration sensitivities over all tested half-sib families correlated negatively with the distribution of decline sensitivity of their parents in a rural Danish seed orchard. The relative photosynthesis and transpiration sensitivities may thus serve as diagnostic parameters for selecting against novel spruce decline.  相似文献   

4.
This paper describes a method for testing the effect of various concentrations of SO2 on lactic acid bacteria from ciders. The media and methods were devised to minimize loss of SO2 due to oxidation or binding with carbonyl compounds. Exposure of laboratory or freshly isolated strains to various concentrations of free SO2 at pH 4·0 did not readily kill them even at high concentrations of free SO2 ( c. 150 p/m or 0·97 p/m molecular SO2) yet they were suppressed at low concentrations ( c. 5 p/m or 0·032 p/m molecular SO2). Reducing the pH to 3·4 reaffirmed how much more effective SO2 is against lactic acid bacteria at lower pH levels because more is present as molecular SO2. As a result of this the idea of quoting SO2 values as p/m molecular SO2 is advocated. Addition of hydrogen peroxide or acetaldehyde to a test system containing 142 p/m free SO2 showed that they had a similar effect in nullifying its antimicrobial properties and allowing the test bacteria to grow. There was no indication that acetaldehyde bisulphite was toxic to the test bacteria.  相似文献   

5.
Five-year-old Picea abies L. plants were grown in growth cabinets in the presence (3.1 μmol m−3) or absence of SO2. After 5 weeks, the photosynthetic capacity of mature needles produced in the year was the same in both conditions. Trees were then submitted in situ to drought stress by withholding water. The decline of leaf photosynthetic capacity was greatest in the presence of SO2. Chlorophyll decreased only when trees were submitted to dehydration in the presence of SO2; however, this al-one could not account for the large decline in photosynthetic capacity observed under that condition. Needle water content was the lowest during dehydration in the presence of SO2. It is concluded that the critical factor in the interaction between pollution by SO2 and drought stress is the greater dehydration of the tissue found in stressed plants grown in the presence of SO2. The large decline in photosynthetic capacity under such conditions might be due to this greater dehydration.  相似文献   

6.
The effect of SO2 on adenosine 5'-phosphosulfate sulfotransferase activity and various other parameters of needles from spruce ( Picea abies L.) was studied using potted grafts in outdoor fumigation chambers and trees growing near a factory. In summer and autumn fumigation of grafted spruce, SO2, decreased the extractable activity of adenosine 5'-phosphosulfate sulfotransferase to 12–50% of the controls, and reduced the amount of 35S from sulphate incorporated into protein by excised branches to a comparable degree. SO2 treatment in January and February inhibited the increase in adenosine 5'phosphosulfate sulfotransferase activity measured in the controls during this time. ATP-sulfurylase activity was less affected by SO2. fumigation. In trees growing near a factory with high SO2. emission, the activity of adenosine 5'-phosphosulfate sulfotransferase was about 35% of that of trees from a control area. The low enzyme activity was correlated with a high content of sulfate and compounds containing thiol groups.  相似文献   

7.
Abstract: This article analyzes the possibilities for reducing carbon dioxide (CO2) emissions in the life cycle of Japanese petrochemicals, focusing primarily on the nonenergy use of fossil fuels. For this purpose a linear programming model called CHEAP (CHemical industry Environmental strategy Analysis Program) has been developed. The results show a moderate autonomous growth of emissions by 5% in the period 2000 to 2020, if it is assumed that no new technology is introduced and demand (measured in physical units) increases 1% per year, on average. However, if it is assumed that ongoing technology development succeeds, emissions in 2020 may decrease by 5% from 2000 levels (a decrease of 10% compared to the case that assumes no new technology). This is a significant contribution to emission reduction. According to this model, a further emission reduction by 10% in 2020 is possible but costly as it requires emission reduction incentives of up to 10,000 yen per ton CO2 (approximately 100 US/ton). The use of biomass feed-stocks, waste recycling, energy recovery from waste and gas-based co-generation are the main strategies for achieving this emission reduction.  相似文献   

8.
Abstract Newly developed low capacity columns were used in suppressed ion chromatography for rapid and highly reproducible determination of SO42− in porewater samples from freshwater sediments without preconcentration of samples. With a 50 μl injection the detection limit for SO42− was ca. 50 pmol (= 1 μ M) with a precision of 1–3% at the 10–200 μM level and <1% at concentrations above 200 μM. SO42− could be measured in 4–5 min with the routinely used eluent (3.0 mM NaHCO3/0.8 mM Na2CO3). When the strength of the eluent was increased to 3.0 mM NaHCO3/2.0 mM Na2CO3, sulfate analysis was possible in less than 3 min, provided that samples were nitrate-free. Under these conditions S2O32− could also be sensitively determined in about 6 min. Examples of application of the method are given for measurements of sulfate reduction rates in freshwater sediment samples from Lake Constance.  相似文献   

9.
The effect of SO2 on the extractable activity of ATP sulfurylase (EC 2.7.7.4.). adenosine 5'-phosphosulfate sulfotransferase, ribulosebisphosphate carboxylase, chlorophyll, protein, sulfate, and amino acids was examined in leaves of potted grafts of beech ( Fagus sylvatica L.) treated in outdoor fumigation chambers. Addition of 0.025 and 0.075 μl SO2 1−1 to unfiltered ambient air caused a decrease in the extractable activity of adenosine 5'-phosphosulfate sulfotransferase to about 20 to 30% of the controls. Neither the extractable activity of ATP sulfurylase and ribulosebisphosphate carboxylase nor the content in chlorophyll, total amino acids and protein were significantly affected by SO2, but there was an increase in the sulfate content. Leaves treated with 0.075 μl SO2 1−1 contained more alanine and cysteine and less serine than the controls. After transfer of the SO2-treated beech trees to control chambers there was an increase in adenosine 5'-phosphosulfate sulfotransferase activity, but no significant decrease in SO2−4-sulfur.  相似文献   

10.
The water fern Azolla pinnata R. Br. was fumigated for 1 week with either 25, 50 or 100 nl 1−1 SO2. The symbiosis of Azolla with Anabaena azollae (spp.) was severely damaged by atmospheric SO2 even at concentrations as low as 25 nl 1−1, with significant reductions in growth, reduction of C2H2, NH3 assimilation, protein synthesis, and heterocyst development. These disturbances appear to be mainly responsible for the extreme sensitivity of this fern to atmospheric SO2. Changes in violaxanthin/antheraxanthin and epoxy-lutein/lutein ratios also indicate that free radical products are induced by atmospheric SO2. These results suggest that the Azolla-Anabaena symbiotic system is a very responsive and reliable lower plant model to study the detailed effects of total sulphur deposition upon the balances between various important plant metabolic processes.  相似文献   

11.
Picea sitchensis (Bong.) Carr. seedlings were exposed to SO2, NO2 and SO2+ NO2 during dormancy in controlled environments, and were taken to night temperatures of 4, 0, −5, −10 and −15 °C in a freezer. Conditions in the freezer were carefully monitored during the low–temperature treatments. In two experiments, different photoenvironments and temperature regimes were imposed prior to the cold treatments, and different effects were observed. In the first, only limited frost hardiness was achieved and night temperatures of −15 °C were lethal. Temperatures of −5 and − 10 °C led to poor survival of lateral buds, particularly in plants exposed to 45 ppb SO2. The poor bud break in plants exposed to SO2 and to − 5 °C resulted in a loss of the effectiveness of this temperature as a chill requirement. Pressure-volume analysis showed that the shoots of plants exposed to NO2 had greater elasticity (lower elastic moduli, e), so that loss of turgor occurred at lower relative water contents. In contrast, a hardening period (2 weeks in night/day temperatures of 3/10 °C and 8 h days at 50 μmol m−2 s−1 PAR) gave decreased elasticity and lower solute potentials of spruce shoots. In the second experiment, exposure to 30 ppb SO2 and SO2+ NO2 led to slight, but consistent, increases in frost injury to the needles of plants frozen to − 5 and − 10 °C. The results suggest that the main interaction of low temperatures and winter pollutants may be on bud survival rather than on needle damage, but that effects are subtle, only occurring with certain combinations of pollutant dose and cold treatment.  相似文献   

12.
To reduce energy consumption and carbon dioxide (CO2) emissions in housing construction, the energy-intensive processes and life-cycle stages should be identified and integrated. The environmental impact of vertically integrated factory-built homes (VIHs) constructed with increased material inputs in Japan's northern island of Hokkaido was assessed using life-cycle inventory (LCI) analysis methods. Manufacturing process energy and CO2 intensities of the homes were evaluated based on the material inputs. They were compared with those of a counterpart home hypothetically built using the vertically integrated construction methods, but in accordance with the specifications of a less material-intensive conventional home (CH) in Hokkaido today. Cumulative household energy consumption and CO2 emissions were evaluated and compared with those of the production stages. The annual household energy consumption was compared among a VIH, a CH, and an average home in Hokkaido. The energy intensity of the VIH was 3.9 GJ production energy per m2 of floor area, 59% higher than that of the CH. Net CO2 emissions during VIH manufacturing processes were 293 kg/m2, after discounting the carbon fixation during tree growth. The cumulative use-phase household energy consumption and CO2 emissions of a VIH will exceed energy consumption and CO2 emissions during the initial production stage in less than six years. Although VIHs housed 21% more residents on average, the energy consumption per m2 was 17% lower than that of a CH. This may indicate that using more materials initially can lead to better energy efficiency.  相似文献   

13.
The effect of Na2SO4 concentrations from 0 to 17.6 m M in the nutrient solution of Lemna minor L. strain 6580 on adenosine 5'-phosphosulfate sulfotransferase activity was examined. Routinely, the plants were cultivated on 0.88 mA SO42−. The enzyme activity was increased by 50 to 100% after transfer to 0 or 0.0088 m M SO42−. Transfer back to 0.88 m M rapidly decreased the enzyme activity to the initial level. Cultivation on 17.6 mM Na2SO4 redueed extractable adenosine 5'-phosphosulfate sulfotransferase by 50%. The original level was rapidly re-established on 0,88 m M . In control experiments, a decrease in adenosine 5'-phosphosulfate sulfotransferase activity was also induced by K2 SO4, whereas NaCl caused a small increase. This indicates that the observed effects are dependent on the sulfate ion. ATP-sulfurylase activity measured for comparison was only significantly affected by the omission of sulfate, which induced a 20% increase, indicating that this enzyme activity from Lemna minor is less suseeptible to changes in medium sulfate than adenosine 5'-phosphosulfate sulfotransferase. A close relationship between adenosine 5'-phosphosulfate sulfotransferase activity and the content of asparagine, glutamine, non-protein thiols and sulfate in the tissue was detected, indicating a positive control mechanism induced by amides and a negative mechanism induced by thiols and sulfate.  相似文献   

14.
The effect of temperature and humidity on SO2–induced photosynthetic depression was determined in gas exchange experiments with leaves of Vicia faba , L. Stomatal behaviour was sensitive to humidity resulting in higher uptake rates of SO2 and stronger reductions of photosynthesis at low VPD (vapour pressure deficit). After a fumigation period of 2 h, when the photosynthetic rate had stabilized, photosynthesis of leaves exposed to SO2 at 8°C was reduced much more than at 18°C at the same rate of SO2 uptake. Data analysis with a mechanistic model revealed that this effect was due to the slower rate of S(IV) oxidation at lower temperatures, resulting in higher accumulation of S(IV) and thus stronger reduction of photosynthesis. These results were confirmed by experimental analyses of the S(IV) concentration in leaves following fumigation, which showed that more S(IV) accumulated in leaves exposed at a lower temperature. This may explain the high sensitivity of plants exposed to SO2 under winter conditions, when both VPD and temperature are low.  相似文献   

15.
Fumigation of spinach (Spinacia oleracea L. cvs Estivato and Monosa) with H2S or SO, for 1 to 6 days resulted in accumulation of sulfhydryl (SH) compounds in the shoots of both H2S- and SO2-exposed plants. The sulfate concentration in shoots of SO2-exposed plants increased linearly with time. SH accumulation showed saturation kinetics as a function of time as well as H2S concentration, ascribed to the internal H2S concentration in the plant and the availability of substrates for glutathione synthesis, respectively. SH compounds accumulated more at lower exposure temperatures, whereas sulfate accumulation was more pronounced at higher temperatures. These results are discussed in relation to the possible foliar uptake of H2S and SO2, the temperature dependence of uptake and the water solubility of these gases. The possibility of SO2-induced H2S emission rather than sulfate accumulation as a source for SH accumulation is also discussed. Cessation of fumigation resulted in a decrease in SH compounds and sulfate content that could be accounted for by sulfur metabolism and growth, respectively.  相似文献   

16.
The effects of elevated gaseous SO2 concentrations in the lichens Evernia prunastri (L.) Ach. and Ramalina farinacea (L.) Ach. were investigated by means of gas exchange, modulated chlorophyll fluorescence analysis and antioxidant enzyme assays. The response to SO2 of the studied species differed markedly. Net photosynthetic rates were more adversely affected in E. prunastri than in R. farinacea . In addition, processes dependent on thylakoid membrane integrity such as PSII-mediated electron flow and nonphotochemical quenching were reduced to a greater extent by exposure to SO2 in E. prunastri . Moreover, the ability to reoxidize the quinone pool was lower in this species. Finally, the activity of chloroplastidic and cytoplasmic antioxidant enzymes was decreased in E. prunastri in response to fumigations but increased in R. farinacea . The results suggest that the ability to process and deal with the SO2 once it has been absorbed must play a role in determining the sensitivity of these lichen species to this air pollutant.  相似文献   

17.
Materials use is an important factor influencing carbon dioxide (CO2) emissions because significant amounts of carbon dioxide are released during the production of materials from natural resources, and because products and wastes can function as important sinks for CO2. This article analyzes the impact of Western European materials use on CO2 emissions. The material flows for steel, cement, petrochemicals, and wood products are analyzed in more detail. The analysis shows that particular characteristics of the materials system must be considered in the development of emission reduction strategies. It is important to select a relatively closed system for policymaking, as in Western Europe, in order to prevent unwanted transboundary effects. The materials stored in the form of products, and the net exports of materials, products, and waste limit the potential of a recycling strategy. Carbon storage in products and waste disposal sites is significant both for synthetic and natural organic materials, but is not accounted for in natural organic materials in current emissions statistics. Accordingly the emissions accounting practices should be modified to reflect the storage of such materials.  相似文献   

18.
Three 9-day-old cultivars of Hordeum vulgare L. (Barberousse, Gerbel and Panda) were exposed to low levels of SO2 fumigation (40 ± 5 and 117 ± 20 ppb). After 48 days of treatment the seedlings were harvested for lipid analysis. In comparison to the control (plants exposed to charcoal-filtered air), the total lipid content of fumigated seedlings declined at 40 ppb SO2 and even more so at 117 ppb in all three cultivars. A large reduction in diacylglycerols. polar lipids and free sterols was also observed after fumigations at both SO2 concentrations, whereas the treatments resulted in an increase in triacylglycerols and free fatty acids. The percentage composition of total fatty acids and that of each lipid class were changed by the fumigations. resulting in an increase in the degree of unsaturation. No changes in the percentage composition of sterols occurred in the fumigated leaves. These results suggest that even if SO2 may not directly oxidize unsaturated fatty acids at the low concentrations used here (which do not cause visible injury). it may alter lipid metabolism. This alteration. which was particularly evident in the polar lipids and sterols, could affect the functions associated with membrane stabilization, in which lipids plus sterols play a key part.  相似文献   

19.
Rainbow trout body mucus dialysed with acidified distilled water at pH 7,5 and 3 experienced ion depletion which was greatest at pH 3 and minimal between pH 7 and 5. Mucus Na+ loss is exacerbated in the presence of 1 mg I−1 aluminium as A12(SO4), at pH 5 and 7. Al2(SO4), causes greater depletion of Na+ from mucus than A1C13. A lethal level of zinc (2 mg 1−1) does not deplete mucus Na or K+, unlike a lethal level of aluminium (1 mg 1−1) at pH 7. The results are discussed in terms of the ionoregulatory role of mucus in heavy metal and acid toxicity.  相似文献   

20.
Plants of three commercial cultivars of Hordeum vulgaris L. (Barberousse, Gerbel, Panda) were continuously exposed to two concentrations of SO2 (40±5 and 117±20 ppb) against a control (charcoal-filtered air). Experiments were performed in fumigation chambers. Fumigation was started 9 days after seeding and plant material was harvested after 48 days. In none of the three cultivars did visible symptoms of injury appear on the leaves after exposure to SO2, while they all showed a reduction in plant height and dry matter of shoots and roots and a significant increase in the shoot/root dry weight ratios depending on the cultivars. The time course of conductivity, and K+ Ca2+ and sugar effluxes were determined for 24 h. Leaves from cvs Gerbel and Panda exposed to SO2 exhibited a progressive increase in conductivity, and in Ca2+ and sugar efflux (expressed as percentages of their total effluxes). Plusmn; efflux of the three cultivars and conductivity in cv. Barberousse increased only after 24 h incubation. A relative leakage ratio (RLR) was calculated from the UV absorption at 280 nm after 24 h incubation of the leaf strips and the total 280 nm UV absorption, obtained after liquid N2 killing of the tissues. The RLR was well correlated with the total amino acids and sugars found in the leachate and can be used as a test for determining the tissue response to SO2.  相似文献   

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