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Karima Bouhafa Lhoussaine Moughli Rachid Bouabid Ahmed Douaik Youness Taarabt 《Journal of plant nutrition》2018,41(8):956-968
The study aims to track the dynamics of the olive leaf nitrogen (N), phosphorus (P) and potassium (K) for five olive varieties under drip irrigation in farmer's fields in central Morocco. Leaf sampling was done every month from May 2014 to April 2015. Leaf macronutrients contents showed variation over time. Olive leaves have maintained the same N content throughout the study period indicating a continuing olive uptake of nitrogen. Higher leaf P absorption was observed during flowering and fruit magnification periods indicating the important P needs of olive during these periods. Olive leaf K levels were higher from September to December indicating the high K needs of olive. No variety effect was revealed on the leaf N, P and K contents. Very highly significant differences were found between the leaf N and K levels measured at different sampling periods. The leaf P concentration was statistically equal in all measuring periods. 相似文献
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Fabrice Monna Lhoussaine Bouchaou Claire Rambeau Rémi Losno Olivier Bruguier Gaetano Dongarrà Stuart Black Carmela Chateau 《Water, air, and soil pollution》2012,223(3):1263-1274
More than 30 epiphytic lichens, collected in Agadir (Morroco) and along a 150-km transect from the Atlantic Ocean eastward,
were analyzed for their metal content and lead isotopic composition. This dataset was used to evaluate atmospheric metal contamination
and the impact of the city on the surrounding area. The concentrations of Cu, Pb, and Zn (average ± 1 SD) were 20.9 ± 15.2 μg g−1, 13.8 ± 9.0 μg g−1, and 56.6 ± 26.6 μg g−1, respectively, with the highest values observed in lichens collected within the urban area. The 206Pb/207Pb and 208Pb/207Pb ratios in the lichens varied from 1.146 to 1.186 and from 2.423 to 2.460, respectively. Alkyllead-gasoline sold in Morocco
by the major petrol companies gave isotopic ratios of 206Pb/207Pb = 1.076–1.081 and 208Pb/207Pb = 2.348–2.360. These new, homogeneous values for gasoline-derived lead improve and update the scarce isotopic database
of potential lead sources in Morocco, and may be of great value to future environmental surveys on the presence of lead in
natural reservoirs, where it persists over time (e.g., soils and sediments). The interest of normalizing metal concentrations
in lichens to concentrations of a lithogenic element is demonstrated by the consistency of the results thus obtained with
lead isotopic ratios. Leaded gasoline contributed less than 50% of the total amount of lead accumulated in lichens, even in
areas subject to high vehicular traffic. This strongly suggests that the recent banishment of leaded gasoline in Morocco will
not trigger a drastic improvement in air quality, at least in Agadir. 相似文献
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