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Johan Bergholm Hooshang Majdi Tryggve Persson 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):225-234
A nitrogen (N) budget was constructed for a period of 6 years (1988–1993) in a Norway spruce stand with current deposition
of 19 kg N and 22 kg S ha−1 year−1. The stand was fertilized annually by addition of 100 kg N and 114 kg S ha−1 (NS). Above and below ground biomass, litterfall, fine- root litter production, soil solution and net mineralization were
measured to estimate pools, fluxes and accumulation of nitrogen. The average needle litterfall in control (C) and NS plots
in 1993 was 2.2 and 2.5 ton ha−1 year−1, respectively. The fine root litter production prior to treatment (1987) was 4.4 ton ha−1 year−1 and after treatment (1993) it was 4.5 and 3.9 ton ha−1 year−1 in C and NS plots, respectively. Net N mineralization in the soil profile down to 50 cm was estimated to be 86 and 115 kg
ha−1 year−1 in C and NS plots, respectively in 1992. During the treatment period the uptake of N in the needle biomass in C and NS plots
was 29 and 77 kg ha−1 year−1, respectively. No N was accumulated in needles of C plot where the NS plots accumulated 34 kg ha−1 year−1. Of the annually added inorganic N to NS plots 47% was accumulated in the above and below ground biomass and 37% in the soil.
N fluxes via fine-root litter production in the C plots were much higher (54 kg ha−1 year−1) than that via litterfall (29 kg ha−1 year−1). The corresponding values in the NS plots were 65 and 43 kg ha−1 year−1, respectively. Most of the net N mineralization occurred in the FH layer and upper mineral soil. It is concluded that fine
root litter and litterfall play an important role in the cycling of N. Despite a high N uptake the losses of N in litterfall
and fine root litter resulted in an incorporation of N in soil organic matter. 相似文献
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Majdi M. Hariri 《Journal of Environmental Planning and Management》1984,27(1):27-33
The problems faced by authorities in Saudi Arabia in managing the large numbers of pilgrims visiting Muna during a brief period each year has led to experiments with aerial photography and computer techniques. This paper describes briefly the new method initiated in 1981 emphasising the remarkably short time available for information assembly and interpretation and concludes with pointers towards the development of the techniques for Third World urbanisation studies. 相似文献
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This paper proposes that there is a need to quantify the value of void-to-solid ratio in residential facades. When quantified, void-to-solid ratio is expected to influence preference for these facades. To test this hypothesis, computer-simulated facades were created using a number of mesh editing and photo-editing software packages. The independent variable, void-to-solid ratio, was varied at three levels of windows' orientations and four levels of buildings' heights, resulting in 60 stimuli. A total of 174 participants were randomly sampled from Mutah University, Jordan, who input a total of 10,440 preference responses to the stimuli. The simulated facades were able to convey the values of void-to-solid ratios to participants. Responses revealed that there is an inverted U-shape relationship between preference for residential facades and their void-to-solid ratio, and that the most preferred range of void-to-solid ratios was (0.4–0.5). 相似文献
4.
The harmful effect of manmade particles on natural processes and human health is documented by a large number of studies showing a positive correlation between particulate matter (PM) concentration and health effects. Diminution of this health risk necessitates among others the precise knowledge of the particle sources, their physical and chemical properties and their dissemination in the environment. Pb isotope ratios have been successfully used during the past decades as tracers of anthropogenic Pb disseminated in the biosphere. Here we show that tree bark biomonitoring with lead (Pb), strontium (Sr) and neodymium (Nd) isotope ratios as tracers allow a thorough analysis of the impacts of industrial and other anthropogenic emissions on the urban environment. This is the first comprehensive multi-isotope tracer study of atmospheric pollution in an urban environment allowing to identify and to integrate the different plume paths of emissions in a digital map system. This innovative approach might become an important tool for environmental management and policy-making processes dealing especially with risks and surveillance of air quality in the urban environment. 相似文献
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Tree bark has been shown to be a useful biomonitor of past air quality because it accumulates atmospheric particulate matter (PM) in its outermost structure. Trace element concentrations of tree bark of more than 73 trees allow to elucidate the impact of past atmospheric pollution on the urban environment of the cities of Strasbourg and Kehl in the Rhine Valley. Compared to the upper continental crust (UCC) tree barks are strongly enriched in Mn, Ni, Cu, Zn, Cd and Pb. To assess the degree of pollution of the different sites in the cities, a geoaccumulation index Igeo was applied. Global pollution by V, Ni, Cr, Sb, Sn and Pb was observed in barks sampled close to traffic axes. Cr, Mo, Cd pollution principally occurred in the industrial area. A total geoaccumulation index IGEO-tot was defined; it is based on the total of the investigated elements and allows to evaluate the global pollution of the studied environment by assembling the Igeo indices on a pollution map. 相似文献
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Abukmeil Reem Barhoum Ali Dher Majdi Yoshida Mitsuo 《Journal of Material Cycles and Waste Management》2022,24(1):4-11
Journal of Material Cycles and Waste Management - The situation of health-care waste in the Gaza Strip was threatening the environment and the public health due to the absence of appropriate... 相似文献
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