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Atmospheric deposition of heavy metals in Slovakia studied by the moss biomonitoring technique, neutron activation analysis and flame atomic absorption spectrometry
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic)) | Florek, M.: Frontasyeva, M. V. | Ermakova, E. V. | Oprea, K. | Pavlov, S. S.
The mosses Pleurozium schreberi, Hylocomium splendes and Dicranum scoparium were used as biomonitors to study the atmospheric deposition of heavy metals on the territory of Slovakia. The samples of mosses were collected on 86 permanent plots. Comparison with limit values from Norway shows strong pollution of the examined areas of Slovakia with many different heavy metals. The maximum level of pollution by heavy metals was observed in the region Gemer-Spis. The most important feature of sampling is that it correlates with the European Moss-Survey-2000 and the results obtained will be incorporated in the Atlas of Heavy Metal Atmospheric Deposition in Europe
显示更多 [+] 显示较少 [-]Sensitivity of adult beech and spruce trees of a mixed forest to chronic ozone exposure: findings from a free-air ozone fumigation experiment
2002
Nunn, A. J. (Technische Universitaet Munchen, Freising (Germany). Lehrstuhl fur Forstbotanik) | Reiter, I. M. | Heerdt, Ch. | Haberle, K. H. | Langerbartels, Ch. | Werner, H. | Sandermann, H. | Fabian, P. | Matyssek, R.
The study aims at assessing response patterns to chronic O3 exposure in adult forest trees, examining physiological and structural responses at the organ and whole-tree level for consistency by means of biochemical and ecophysiological analyses. Through comparison between the two O3 regimes, conclusions can be drawn about processes, which are at risk or already affected by ozone under the unchanged, prevailing stand conditions. Responses are related to the O3 influx into leaves as a measure of the physiologically effective O3 dose and cross-compared with the AOT 40 concept which is being validated on the two O3 fluxes and AOT40-related responses in biochemical, ecophysiological and structural tree parameters
显示更多 [+] 显示较少 [-]Possibilities of biological reclamation of sludge fields in aluminium plant in Ziar nad Hronom
2002
Varga, L. (Forest Research Institute, Gabcikovo (Slovak Republic). Research Station)
The solution for waste disposal being formed in the production of aluminium in Aluminium plant in Ziar nad Hronom is presented. It is namely recultivation of waste pile, it means biological reclamation. Averagely high vegetation is considered the most effective one for the reclamation of devastated areas and for creating natural connection of different components of this environment. Experimental plantations on the pile established in the years 1993-1996 by FRI Zvolen unanimously confirm this finding
显示更多 [+] 显示较少 [-]Can air pollution influence spruce bark beetle populations in the Central European mountains?
2002
Turcani, M. (Forest Research Institute, Banska Stiavnica (Slovak Republic). Forest Station) | Grodzki, W. | Fleischer, P. | Novotny, J.
Bark beetle populations were estimated periodically each year in 50 ha plots using a series of pheromone traps and through the dissection of 0.5 m sections of infested trees. Data were recorded on several parameters including the volume of infested trees, captures in pheromone traps, number of attacks, and the presence and relative abundance of related bark beetle species. In the period 2000-2001 3 transects were established in the High Tatra Mts., where captures in pheromone traps were recorded and compared with air pollution represented by ozone
显示更多 [+] 显示较少 [-]Science and policy - to what extent does long-term monitoring of forest ecosystems contribute to policy relevant air pollution issues?
2002
Haussmann, T. (Federal Ministry of Consumer Protection, Food and Agriculture, Bonn (Germany)) | Fischer, R. | Riebau, A.
Science and policy - to what extent does long-term monitoring of forest ecosystems contribute to policy relevant air pollution issues?
2002
Haussmann, T. (Federal Ministry of Consumer Protection, Food and Agriculture, Bonn (Germany)) | Fischer, R. | Riebau, A.
Following the objective to provide an overview on the spatial and temporal variation in forest condition on a European scale, an extensive systematic survey on more than 6000 so called Level I plots throughout Europe is carried out. Results show a recuparation of crown condition in the mid nineties and a resuming deterioration with nearly a quarter of the sample trees classified as damaged in 2001. Results of statistical evaluations explain the observed variation mainly by weather extremes, insects, fungi and indirect effects of air pollutants via soil acidification or changes in the nutritional status of trees
显示更多 [+] 显示较少 [-]Science and policy - to what extent does long-term monitoring of forest ecosystems contribute to policy relevant air pollution issues?
2002
Haussmann T. | Fischer R. | Riebau A.
Following the objective to provide an overview on the spatial and temporal variation in forest condition on a European scale, an extensive systematic survey on more than 6000 so called Level I plots throughout Europe is carried out. Results show a recuparation of crown condition in the mid nineties and a resuming deterioration with nearly a quarter of the sample trees classified as damaged in 2001. Results of statistical evaluations explain the observed variation mainly by weather extremes, insects, fungi and indirect effects of air pollutants via soil acidification or changes in the nutritional status of trees.
显示更多 [+] 显示较少 [-]Estimating down deadwood from FIA forest inventory variables in Maine 全文
2002
Down deadwood (DDW) is a carbon component important in the function and structure of forest ecosystems, but estimating DDW is problematic because these data are not widely available in forest inventory databases. However, DDW data were collected on USDA Forest Service Forest Inventory and Analysis (FIA) plots during Maine's 1995 inventory. This study examines ways to predict DDW biomass from other FIA variables so that DDW could be estimated without tedious measurement. Our results include a regression model that predicts DDW as a function of stand size class, basal area of dead and cut trees, and dummy variables for forest type and forest industry ownership. We also found DDW similar to FIA's standing-tree mortality at a statewide scale.
显示更多 [+] 显示较少 [-]Evaluation of Atriplex lines for selenium accumulation, salt tolerance and suitability for a key agricultural insect pest 全文
2002
Vickerman, D.B. | Shannon, M.C. | Banuelos, G.S. | Grieve, C.M. | Trumble, J.T.
Thirty Atriplex lines were examined for potential habitat improvement and phytoremediation of selenium (Se) contaminated sites. Studies were conducted to determine the biomass production, Se accumulation, and resistance of each line to the beet armyworm, Spodoptera exigua, an agriculturally important insect. Plants were tested using three salinity treatments: (1) control, no Se; (2) NaCl and CaCl2 salts and 1 mg l-1 Se (12.7 μM) added as sodium selenate; and (3) iso-osmotic to treatment 2 containing high concentrations of sulfate and 1 mg l-1 Se added as sodium selenate. Insect bioassays measured survival, growth, and development. Atriplex patula, A. spongiosa 415862, A. hortensis, A. hortensis 379088 and A. hortensis 379092 were among the top biomass producers and Se accumulators, yet they exhibited significantly reduced insect growth, development, and survival. High background sulfate strongly reduced Se accumulation, suggesting that phytoremediation potential is greatest in saline areas having low to moderate sulfate levels. However, these lines grew well in high salinity soils, indicating possible use as a self-seeding cover crop to improve habitat. All plant lines grown in control and high sulfate salinity treatments are acceptable oviposition sites for S. exigua, indicating that these plants would help reduce populations of this key agricultural pest.
显示更多 [+] 显示较少 [-]Particulate and non-particulate fractions of soil organic carbon under pastures in the Southern Piedmont USA 全文
2002
Pasture management can be effective at sequestering soil organic C. We determined the depth distribution of particulate organic C (POC), non-particulate organic C (NPOC), particulate-to-total organic C (POC-to-TOC) ratio, and particulate organic C-to-N (POC-to-N) ratio under pastures near Watkinsville, GA, USA. POC was highly related with total organic C (TOC), but became an increasingly larger portion of TOC near the soil surface, where both pools were greatest. POC and NPOC were (i) greater under pasture than under conservation-tillage cropland, (ii) greater when pasture was grazed than when hayed, (iii) marginally greater with higher fertilization of pasture, (iv) greater with higher frequency of endophyte infection of tall fescue, and (v) greater under increasing stand age of grass. Soil under pasture comparisons that had greater TOC content had (i) larger improvements in POC than in NPOC and (ii) lower POC-to-N ratios, suggesting improvement in biochemical soil quality, as well as soil C sequestration.
显示更多 [+] 显示较少 [-]Simulated effects of dryland cropping intensification on soil organic matter and greenhouse gas exchanges using the DAYCENT ecosystem model 全文
2002
Del Grosso, S. | Ojima, D. | Parton, W. | Mosier, A. | Peterson, G. | Schimel, D.
We present evidence to show that DAYCENT can reliably simulate soil C levels, crop yields, and annual trace gas fluxes for various soils. DAYCENT was applied to compare the net greenhouse gas fluxes for soils under different land uses. To calculate net greenhouse gas flux we accounted for changes in soil organic C, the C equivalents of N2O emissions and CH4 uptake, and the CO2 costs of N fertilizer production. Model results and data show that dryland soils that are depleted of C due to conventional till winter wheat/fallow cropping can store C upon conversion to no till, by reducing the fallow period, or by reversion to native vegetation. However, model results suggest that dryland agricultural soils will still be net sources of greenhouse gases although the magnitude of the source can be significantly reduced and yields can be increased upon conversion to no till annual cropping.
显示更多 [+] 显示较少 [-]Polyacrylamide preparations for protection of water quality threatened by agricultural runoff contaminants 全文
2002
Entry, J.A. | Sojka, R.E. | Watwood, M. | Ross, C.
Waste streams associated with a variety of agricultural runoff sources are major contributors of nutrients, pesticides and enteric microorganisms to surface and ground waters. Water soluble anionic polyacrylamide (PAM) was found to be a highly effective erosion-preventing and infiltration-enhancing polymer, when applied at rates of 1-10 g m (super -3) in furrow irrigation water. Water flowing from PAM treated irrigation furrows show large reductions in sediment, nutrients and pesticides. Recently PAM and PAM+CaO and PAM+Al(SO (sub 4) ) (sub 3) mixtures have been shown to filter bacteria, fungi and nutrients from animal wastewater. Low concentrations of PAM [175-350 g PAM ha (super -1) as PAM or as PAM+CaO and PAM+Al(SO (sub 4) ) mixture] applied to the soil surface, resulted in dramatic decreases (10 fold) of total, coliform and fecal streptococci bacteria in cattle, fish and swine wastewater leachate and surface runoff. PAM treatment also filtered significant amounts of NH (sub 4) , PO (sub 4) and total P in cattle and swine wastewater. This points to the potential of developing PAM as a water quality protection measure in combination with large-scale animal feeding operations. Potential benefits of PAM treatment of animal facility waste streams include: (1) low cost, (2) easy and quick application, (3) suitability for use with other pollution reduction techniques. Research on the efficacy of PAM for removal of protozoan parasites and viruses and more thorough assessment of PAM degradation in different soils is still needed to completely evaluate PAM treatment as an effective waste water treatment. We will present analysis and feasibility of using PAM, PAM+Al(SO (sub 4) ) (sub 3) , and PAM+CaO application for specific applications. Our results demonstrate their potential efficacy in reducing sediment, nutrients and microorganisms from animal production facility effluents. Abstract
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