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Forest decline and soil nutritional problems in Pacific areas.
1990
Mueller Dombois D.
Phosphorus sorption in subsurface constructed wetlands: investigations focused on calcareous materials and their chemical reactions
2002
Molle, Pascal | Lienard, A. | Grasmick, A. | Iwema, A.
Phosphorus removal from wastewater has been of growing interest for some decades to avoid eutrophication in surface water. In subsurface constructed wetlands precipitation and adsorption are the main mechanisms responsible of P uptake. The use of calcareous media is attractive because of p-ca interactions. Two media (calcite and recycled crushed concrete (rcc)) were examined in batch and continuous systems. They show attractive sorption capacities using batch experiments, however experiments carried out in open reactors pointed out some limitation in retention capacities and effluent quality. rcc was sensitive to a strong dissolution leading to a quick phosphorus precipitation but induced high conductivity and ph values in the treated water. Calcite efficiency depended on the material dissolution rate, directly linked to the carbonate equilibrium of the solution. Microscopic observations of the calcite surface show crystal making of phosphorus precipitate. Crystal growth seems to be the main P uptake once materials surfaces are covered. No experimental condition allows to reach an effluent concentration below 2 mgp.l-1.
显示更多 [+] 显示较少 [-]Variation factors of some minerals in camel milk
2008
Konuspayeva, Gaukhar | Narmuratova, Meiramkul | Meldebekova, Aliya | Faye, Bernard | Loiseau, Gérard
In four regions of Kazakhstan (Atyrau, Aralsk, Shymkent and Almaty), a survey on camel farms was achieved in order to study the variability of the physico-chemical composition of camel milk both in dromedary (Camelus dromedarius) and Bactrian (Camelus bactrianus) camel as well as their hybrids. As the whole, 163 milk samples were analyzed for calcium, phosphorus and iron determination. In order to maximize the variance, the samples were done in four different seasons which expressed the feeding change and the physiological stage changes as the calving season was concentrated in few months. The mean values were respectively 1.232 ± 0.292 g/l, 1.003 ± 0.217 g/l and 2.02 ± 1.24 mg/l for calcium, phosphorus and iron. No species, season or region effect was observed on iron content in the milk. Calcium and phosphorus change significantly according to season and species, but only phosphorus was linked to region effect. Especially phosphorus content is high in Aralsk region (1.156 ± 0.279 g/l). Globally, it is noticeable to observe the high level of phosphorus in the camel milk of Kazakhstan compared to the literature's results. (Résumé d'auteur)
显示更多 [+] 显示较少 [-]Interactive effects of aluminum, phosphorus and mycorrhizae on growth and nutrient uptake of Panicum virgatum L. (Poaceae)
1989
Koslowsky, S.D. | Boerner, R.E.J. (Department of Botany, Ohio State University, Columbus, OH 43210 (USA))
Effects of air pollutants on vegetation in the region of Sfax (Tunisia) [cultivated and wild plants]
1990
Ben Abdallah, F. (Faculte des Sciences de Sfax (Tunisia)) | Boukhris, M.
Evaluation of hydroxyapatite as a metal immobilizing soil additive for the remediation of polluted soils. Part 1. Influence of hydroxyapatite on metal exchangeability in soil, plant growth and plant metal accumulation
1999
Boisson, J. | Ruttens, A. | Mench, M. | Vangronsveld, J. (INRA Bordeaux Aquitaine Research Center, Agronomy Unit, BP 81, F-33883 Villenave d'Ornon (France))
Towards integrated national modelling with particular reference to the environmental effects of nutrients
1998
Alkemade, J.R.M. | Grinsven, J.J.M. van | Wiertz, J. | Kros, J. (National Institute of Public Health and the Environment, Bilthoven (Netherlands))
Effects of eutrophication in drainage ditches
1998
Janse, J.H. | Puijenbroek, P.J.T.M. van (RIVM, Laboratory of Water and Drinking Water Research, P.O. Box 1, NL-3720 BA Bilthoven (Netherlands))
Nitrogen in Dutch freshwater lakes: trends and targets
1998
Molen, D.T. van der | Portielje, R. | Nobel, W.T. de | Boers, P.C.M. (Institute for Inland Water Management and Waste Water Treatment, Lelystad (Netherlands))
Downward movement of cadmium and phosphorus from phosphatic fertilisers in a pasture soil in New Zealand
1997
Loganathan, P. | Hedley, M.J. (Fertilizer and Lime Research Centre, Massey University, Palmerston North (New Zealand))