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901.
The variations of aluminium species in mountainous forest soils and its implications to soil acidification 总被引:1,自引:0,他引:1
Monika?BradováEmail author Václav?Tejnecky Lubo??Bor?vka Karel?Něme?ek Christopher?Ash Ond?ej??ebek Miroslav?Svoboda Jitka?Zenáhlíková Ond?ej?Drábek 《Environmental science and pollution research international》2015,22(21):16676-16687
Aluminium (Al) speciation is a characteristic that can be used as a tool for describing the soil acidification process. The question that was answered is how tree species (beech vs spruce) and type of soil horizon affect Al speciation. Our hypotesis is that spruce and beech forest vegetation are able to modify the chemical characteristics of organic horizon, hence the content of Al species. Moreover, these characteristics are seasonally dependent. To answer these questions, a detailed chromatographic speciation of Al in forest soils under contrasting tree species was performed. The Jizera Mountains area (Czech Republic) was chosen as a representative mountainous soil ecosystem. A basic forestry survey was performed on the investigated area. Soil and precipitation samples (throughfall, stemflow) were collected under both beech and spruce stands at monthly intervals from April to November during the years 2008–2011. Total aluminium content and Al speciation, pH, and dissolved organic carbon were determined in aqueous soil extracts and in precipitation samples. We found that the most important factors affecting the chemistry of soils, hence content of the Al species, are soil horizons and vegetation cover. pH strongly affects the amount of Al species under both forests. Fermentation (F) and humified (H) organic horizons contain a higher content of water extractable Al and Al3+ compared to organo-mineral (A) and mineral horizons (B). With increasing soil profile depth, the amount of water extractable Al, Al3+ and moisture decreases. The prevailing water-extractable species of Al in all studied soils and profiles under both spruce and beech forests were organically bound monovalent Al species. Distinct seasonal variations in organic and mineral soil horizons were found under both spruce and beech forests. Maximum concentrations of water-extractable Al and Al3+ were determined in the summer, and the lowest in spring. 相似文献
902.
Ewa Łuszczek-Trojnar Ewa Drąg-Kozak Włodzimierz Popek 《Environmental science and pollution research international》2013,20(5):3122-3132
We studied the bioaccumulation of lead in selected tissues of Prussian carp Carassius gibelio (Bloch, 1782) during 12 and 24 months exposure to different doses of this metal in feed and the elimination of lead from tissues during the following 12-month depuration period. Lead concentration was determined using atomic absorption spectrometry method. The highest lead concentrations were observed at 2.0?±?0.54 to 7.4?±?1.1 mg?kg?1 in the kidney, 3.0?±?0.13 to 5.2?±?0.17 mg?kg?1 in the bone, and 4.5 (±0.4)?mg?kg?1 in the hepatopancreas of fish from groups exposed to lead dietary concentration from 8 to 49 mg?kg?1 for 24 months. The rate of accumulation were generally the highest at the beginning of exposure as evidenced by the highest monthly increments of bioaccumulation observed after 3 months of contamination for muscles, hepatopancreatic gland, intestine, and gills. Also analysis of the monthly increments of lead bioaccumulation in bone tissue and the highly significant coefficients of correlation indicate that the dynamics of accumulation are clearly dependent on dose of exposure. Depuration of accumulated lead from the organs depended mainly on tissue and duration of elimination period. Very rapid depuration was observed in soft tissues such as the intestine or muscles. Very low elimination was observed for scales and bones where until the end of the experiment highly significant lead concentration differences were observed in all groups in relation to the control group. Chronic dietary exposure in the range of 8–49 mg Pb?kg?1 resulted in no significant effects on the growth and survival of Prussian carp females. 相似文献
903.
The Journal of the Air Pollution Control Association presents its third directory of air pollution control consultants. This 8-page guide lists individual consultants and firms who have indicated a capability in this field by responding to a questionnaire published in three consecutive issues of the Journal. The listing gives corporate names, addresses and phone numbers alphabetically within five broad geographic areas which are shown below. 相似文献
904.
Carl M. Shy M.D. Dr. P.H John P. Creason M.S. Martin E. Pearlman M.D. Kathryn E. McClain Ferris B. Benson Marion M. Young M.D. 《Journal of the Air & Waste Management Association (1995)》2013,63(9):582-588
A study of acute respiratory illness was conducted from November 1968 through April 1969 among families residing in an area of relatively high nitrogen dioxide exposure, in an area of elevated suspended particulate exposure, and in two control areas of Greater Chattanooga. Respiratory illness rates were consistently higher in all family segments in the high-nitrogen dioxide exposure area when rates were averaged for the entire 24 weeks of study, the A2/Hong-Kong epidemic period, or post-epidemic interval. A relative excess in respiratory illness of 18.8 percent was found among families exposed to elevated NO2 concentrations and an excess of 10.4 percent was found among families in the elevated-suspended particulate exposure area. 相似文献
905.
906.
Bart Vandecasteele Gijs Du Laing Kurt Jordaens 《Environmental pollution (Barking, Essex : 1987)》2010,158(6):2181-2188
Soil amendments previously shown to be effective in reducing metal bioavailability and/or mobility in calcareous metal-polluted soils were tested on a calcareous dredged sediment-derived soil with 26 mg Cd/kg dry soil, 2200 mg Cr/kg dry soil, 220 mg Pb/kg dry soil, and 3000 mg Zn/kg dry soil. The amendments were 5% modified aluminosilicate (AS), 10% w/w lignin, 1% w/w diammonium phosphate (DAP, (NH4)2HPO4), 1% w/w MnO, and 5% w/w CaSO4. In an additional treatment, the contaminated soil was submerged. Endpoints were metal uptake in Salix cinerea and Lumbricus terrestris, and effect on oxidation-reduction potential (ORP) in submerged soils. Results illustrated that the selected soil amendments were not effective in reducing ecological risk to vegetation or soil inhabiting invertebrates, as metal uptake in willows and earthworms did not significantly decrease following their application. Flooding the polluted soil resulted in metal uptake in S. cinerea comparable with concentrations for an uncontaminated soil. 相似文献
907.
Hatch L Clark C Merrick R Van Parijs S Ponirakis D Schwehr K Thompson M Wiley D 《Environmental management》2008,42(5):735-752
In 2006, we used the U.S. Coast Guard’s Automatic Identification System (AIS) to describe patterns of large commercial ship
traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial
vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of
the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston
Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We
combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months
in 2006. Analysis of received sound levels (10–1000 Hz, root-mean-square pressure re 1 μPa ± SE) averaged 119.5 ± 0.3 dB at
high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the
majority of the time period analyzed. Average source level estimates (71–141 Hz, root-mean-square pressure re 1 μPa ± SE)
for individual vessels ranged from 158 ± 2 dB (research vessel) to 186 ± 2 dB (oil tanker). Tankers were estimated to contribute
2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results
indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers
regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
908.
Dr Jo Williams 《Journal of Environmental Planning and Management》2008,51(1):107-140
The new housing growth programme planned for England and Wales between now and 2016 could provide the government with an opportunity to build housing to significantly higher environmental performance (EP) standards. Equally, if the government continues with its current strategy a great opportunity could be missed. This paper considers and critically analyses the government's approach to ensuring higher EP standards in new housing. Using Greenwich Millennium Village as a case study it assesses the likely outcomes of the approach. It suggests how regulation, fiscal incentives and educational programmes could help to deliver better EP amongst housing and households in the growth region. 相似文献
909.
Incentives for low-input land-use types and their influence on the attractiveness of landscapes 总被引:1,自引:0,他引:1
Changes in agricultural policy have traceable effects on landscape aesthetics. For the catchment area of Lake Greifensee, an economic land-use model predicted land-use changes caused by agricultural policy. Three scenarios implementing different direct payment schemes show that land-use intensity will decrease by 2011 compared with the ‘reference status’ 2000.The output of the economic land-use model is explicit in space. It was assessed by the ‘naturalness’ perception factor of the method proposed by Hoisl et al. [1989. Landschaftsästhetik in der Flurbereinigung. Materialien zur Flurbereinigung—Heft 17. Bayerisches Staatsministerium für Ernährung, Landwirtschaft und Forsten, München] with regard to landscape aesthetics. Even though lower land-use intensity is generally predicted by 2011, the values of the ‘naturalness’ perception factor do not significantly improve if the payment scheme remains unchanged, or if the payment scheme is amended by incentives for specific location of the ecological compensation areas (ECAs). A significant reduction in the values of the ‘naturalness’ perception factor was found when subsidies for ECA's were cancelled. This leads us to the conclusion that in order to keep Swiss landscapes as attractive as they are at present, policy must sustain incentives for low-intensity land-use types. 相似文献
910.
Biochar: a synthesis of its agronomic impact beyond carbon sequestration 总被引:13,自引:0,他引:13
Spokas KA Cantrell KB Novak JM Archer DW Ippolito JA Collins HP Boateng AA Lima IM Lamb MC McAloon AJ Lentz RD Nichols KA 《Journal of environmental quality》2012,41(4):973-989
Biochar has been heralded as an amendment to revitalize degraded soils, improve soil carbon sequestration, increase agronomic productivity, and enter into future carbon trading markets. However, scientific and economic technicalties may limit the ability of biochar to consistently deliver on these expectations. Past research has demonstrated that biochar is part of the black carbon continuum with variable properties due to the net result of production (e.g., feedstock and pyrolysis conditions) and postproduction factors (storage or activation). Therefore, biochar is not a single entity but rather spans a wide range of black carbon forms. Biochar is black carbon, but not all black carbon is biochar. Agronomic benefits arising from biochar additions to degraded soils have been emphasized, but negligible and negative agronomic effects have also been reported. Fifty percent of the reviewed studies reported yield increases after black carbon or biochar additions, with the remainder of the studies reporting alarming decreases to no significant differences. Hardwood biochar (black carbon) produced by traditional methods (kilns or soil pits) possessed the most consistent yield increases when added to soils. The universality of this conclusion requires further evaluation due to the highly skewed feedstock preferences within existing studies. With global population expanding while the amount of arable land remains limited, restoring soil quality to nonproductive soils could be key to meeting future global food production, food security, and energy supplies; biochar may play a role in this endeavor. Biochar economics are often marginally viable and are tightly tied to the assumed duration of agronomic benefits. Further research is needed to determine the conditions under which biochar can provide economic and agronomic benefits and to elucidate the fundamental mechanisms responsible for these benefits. 相似文献