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The contribution of ammonia emissions from agriculture to the deposition of acidifying and eutrophying compounds onto forests.
1989
Draaijers G.P.J. | Ivens W.P.M.F. | Bos M.M. | Bleuten W.
Patterns of fluoride accumulation and growth reduction exhibited by Douglas fir in the vicinity of an aluminum reduction plant.
1984
Taylor R.J. | Basabe F.A.
Foliar leaching and root uptake of Ca, Mg and K in relation to acid fog effects on Douglas-fir.
1990
Turner D.P. | Tingey D.T.
Changes in phytomass and nutrient partitioning in young conifers in extreme alkaline growth conditions
1999
Mandre, M. | Kloseiko, J. | Ots, K. | Tuulmets, L. (Estonian Agricultural University, Forest Research Institute, Department of Ecophysiology, Viljandi mnt.18b, Tallinn 11216 (Estonia))
Effects of formaldehyde-enriched mists on Pseudotsuga menziesii (Mirbel) Franco and Lobaria pulmonaria (L.) Hoffm
1996
Muir, P.S. | Shirazi, A.M. (Department of Botany and Plant Pathology, Oregon State University, Cordley Hall 2082, Corvallis, OR 97331-2902 (USA))
Nutrient leaching from conifer needles in relation to foliar apoplast cation exchange capacity
1992
Turner, D.P. | Broekhuizen, H.J. van (Mantech Environmental Technology, Inc., US EPA Environmental Research Laboratory, 200 S.W. 35th, Corvallis, Oregon 97333 (USA))
Measurement of dry deposition of ammonia on a forest
1992
Wyers, G.P. | Vermeulen, A.T. | Slanina, J. (Netherlands Energy Research Foundation, PO Box 1, 1755 ZG Petten (Netherlands))
Measurement of the dry deposition flux of NH(3) on to coniferous forest
1992
Duyzer, J.H. | Verhagen, H.L.M. | Weststrate, J.H. (TNO Institute of Environmental Sciences, PO Box 6011, 2600 JA Delft (Netherlands))
X-ray Microanalysis of Needles from Douglas Fir Growing in Environments of Contrasting Acidity
2007
Sangster, Allan G | Ling, Lewis | Gérard, Frédéric | Hodson, Martin J
Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] shoots from mature trees were collected from two sites of contrasting soil pH: the Glendon campus of York University in Toronto, Canada (pH 6.7 at 40 cm) designated Can.; and Breuil Forest, Morvan, France (pH 4 to 4.5) designated Fr.. Needles were removed from the shoots, frozen in liquid nitrogen, and kept in a cryo-biological storage system prior to X-ray microanalysis on the cold stage (-170°C) of a cryo-SEM. Four elements detected, potassium, phosphorus, sulphur and chlorine, were ubiquitous in the needle tissues from both sites. Manganese was infrequently found in needle tissues from the Fr. site. Calcium was localized most heavily in the outer tangential wall of the hypodermis and also in the epidermal walls. Silicon (Si) concentrations were higher in the Fr. site than in the Can. site. The epidermis, hypodermis and mesophyll of needles from the Fr. site exhibited the highest Si content, with greater amounts in the tip and middle of the needle than in the base. Aluminium was distributed fairly evenly throughout the tissues, and there were few major sites of concentration.
Afficher plus [+] Moins [-]Optimization of Lead and Cadmium Binding by Oxidation of Biosorbent Polysaccharidic Moieties
2012
Hachem, Kadda | Astier, Cédric | Chaleix, Vincent | Faugeron, Céline | Krausz, Pierre | Kaid-Harche, Meriem | Gloaguen, Vincent
The polysaccharidic moieties of three biosorbents (Douglas fir and argan tree barks and argan endocarp) were selectively oxidized, and the subsequent modified materials were tested for their ability to bind Pb(II) or Cd(II) from aqueous solutions. Chemical modifications consisted in two selective oxidations, alone or in combination, of the following groups: primary alcohols with NaOBr catalyzed by (2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl, and vicinal diols with periodate/chlorite. The sodium chlorite oxidation step induced biosorbent degradation that led to a significant decrease of mass yield. Modified materials, characterized by FT-IR spectroscopy and measurement of surface acidity, were investigated for their adsorption capabilities of Cd(II) and Pb(II). Results were compared to the capabilities of crude materials using the Langmuir adsorption model in terms of affinity (b) and maximum binding capacity (q ₘₐₓ). Ion exchange properties were found better for lead than for cadmium before and after chemical modifications. Compared to crude barks, the best results were obtained for Douglas fir barks whose oxidation resulted in significant enhancements of q ₘₐₓ up to × 10 in the case of lead.
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