نتایج جستجو برای: mineral soil

تعداد نتایج: 241679  

2017
Elana Dayoub Christophe Naudin Guillaume Piva Steven J. Shirtliffe Joëlle Fustec Guénaëlle Corre-Hellou

Legume crops are known to have low soil N uptake early in their life cycle, which can weaken their ability to compete with other species, such as weeds or other crops in intercropping systems. However, there is limited knowledge on the main traits involved in soil N uptake during early growth and for a range of species. The objective of this research was to identify the main traits explaining t...

2010
Jason A. Dittman James B. Shanley Charles T. Driscoll George R. Aiken Ann T. Chalmers Janet E. Towse Pranesh Selvendiran

[1] Mercury (Hg) contamination is widespread in remote areas of the northeastern United States. Forested uplands have accumulated a large reservoir of Hg in soil from decades of elevated anthropogenic deposition that can be released episodically to stream water during high flows. The objective of this study was to evaluate spatial and temporal variations in stream water Hg species and organic m...

Journal: :Applied and environmental microbiology 2010
David J Levy-Booth Richard S Winder

The abundance of nifH, nirS, and nirK gene fragments involved in nitrogen (N) fixation and denitrification in thinned second-growth Douglas-fir (Pseudotsuga menziesii subsp. menziesii [Mirb.] Franco) forest soil was investigated by using quantitative real-time PCR. Prokaryotic N cycling is an important aspect of N availability in forest soil. The abundance of universal nifH, Azotobacter sp.-spe...

Journal: :Journal of environmental quality 2001
A S Chan T B Parkin

Methane (CH4) flux from soil to the atmosphere is the result of two microbial processes, methanogenesis and CH4 oxidation. Land use may have a profound impact on the relative activities of these groups of organisms. In this study, the CH4 production and consumption potentials of soils from agricultural and nonagricultural ecosystems were assessed in laboratory incubations. Methane production po...

2012
Joanna Lemanowicz

The aim of this study was to determine the effect of mineral fertilization on the activity of alkaline and acid phosphatase and content of available phosphorus in soil under winter wheat cultivation. The fi rst factor of experiment was the fertilization with P, K, Mg, Ca and S in six levels: 1 (P, K, Mg, Ca and S), 2 (K, Mg, Ca and S), 3 (P, Mg, Ca and S), 4 (P, K, Ca and S), 5 (P, K, Mg, Ca), ...

2016
Filip Oulehle Michal Růžek Karolina Tahovská Jiří Bárta

We compared two adjacent mature forest ecosystem types (spruce vs. beech) to unravel the fate of assimilated carbon (C) and the cycling of organic and inorganic nitrogen (N) without the risk of the confounding influences of climatic and site differences when comparing different sites. The stock of C in biomass was higher (258 t·ha−1) in the older (150 years) beech stand compared to the younger ...

2012
Kevin E. Mueller David M. Eissenstat Sarah E. Hobbie Jacek Oleksyn Andrzej M. Jagodzinski Peter B. Reich Oliver A. Chadwick Jon Chorover

Forest biogeochemical cycles are shaped by effects of dominant tree species on soils, but the underlying mechanisms are not well understood. We investigated effects of temperate tree species on interactions among carbon (C), nitrogen (N), and acidity in mineral soils from an experiment with replicated monocultures of 14 tree species. To identify how trees affected these soil properties, we eval...

2008
JOHANNES LEHMANN DAWIT SOLOMON JAMES KINYANGI CHRIS JACOBSEN

Organic matter in soil has been suggested to be composed of a complex mixture of identifiable biopolymers rather than a chemically complex humic material. Despite the importance of the spatial arrangement of organic matter forms in soil, its characterization has been hampered by the lack of a method for analysis at fine scales. X-ray spectromicroscopy has enabled the identification of spatial v...

2009
T. A. Douglas M. E. Walsh T. P. Trainor

We investigated the fate of explosives compounds in slurries containing fractured and weathered soil particles. Three soils were crushed with a piston to emulate detonation-induced fracturing. We used X-ray diffraction, scanning electron microscopy and gas adsorption surface area measurements to quantify the mineralogies and surfaces of the weathered and fractured soil particles. Soil batch slu...

2017
Akihiko Ito Rota Wagai

Clay-size minerals play important roles in terrestrial biogeochemistry and atmospheric physics, but their data have been only partially compiled at global scale. We present a global dataset of clay-size minerals in the topsoil and subsoil at different spatial resolutions. The data of soil clay and its mineralogical composition were gathered through a literature survey and aggregated by soil ord...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید