Physical Sciences and Mathematics | Open Access Articles

Net Geochemical Release Of Base Cations From 25 Forested Watersheds In The Catskill Region Of New York, Sara C. Nieman, Chris E. Johnson

Civil and Environmental Engineering

Chemical weathering of minerals is the principal mechanism by which base cations (Ca²⁺, Mg²⁺, K⁺, and Na⁺) are released and acidity is neutralized in soils, bedrock and drainage waters. Quantifying the release of base cations from watershed soils is therefore crucial for the calculation of “critical loads” of atmospheric acidity to forest ecosystems. We used a mass-balance approach to estimate the rate of release of base cations in 25 headwater catchments in the Catskill region of New York, an area historically subject to high inputs of acid deposition. In 2010-2013, total net …

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Digital Mapping Of Togo’S Soil Fertility: Savannah Region, Aminou Saibou

English Language Institute

A soil assessment was carried out in the savannah region of Togo in 2018, aiming at drawing the digital map of Togo’s soil fertility and making fertilizer recommendations. Soil samples were taken from geo-referenced GPS points and were analyzed for parameters such as water pH, Organic matter, available phosphorus and exchangeable potassium. Thematic maps have been drawn using an ArcGIS package. The results showed that the soils of the Savannah region in Togo are mainly (84%) not very acidic (pH = 5.5 to 6.5), overall poor to very poor (84%) in organic matter (<2% OM), essentially poor to very poor (86%) in available phosphorus (<15 mg/kg of soil) and mostly very poor (87%) in exchangeable potassium (<90 mg / kg of soil). These results allowed the agricultural research institute of Togo to make fertilizer use recommendations and to develop, in partnership with Morocco, a digital platform (fertitogo.tg ) for decision making in crop fertilization.

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Silica Uptake And Release In Live And Decaying Biomass In A Northern Hardwood Forest, Wim Clymans, Daniel J. Conley, John J. Battles, Patrick J. Frings, Mary Margaret Koppers, Gene E. Likens, Chris E. Johnson

Civil and Environmental Engineering

In terrestrial ecosystems, a large portion (20–80%) of the dissolved Si (DSi) in soil solution has passed through vegetation. While the importance of this “terrestrial Si filter” is generally accepted, few data exist on the pools and fluxes of Si in forest vegetation and the rate of release of Si from decomposing plant tissues. We quantified the pools and fluxes of Si through vegetation and coarse woody debris (CWD) in a northern hardwood forest ecosystem (Watershed 6, W6) at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, USA. Previous work suggested that the decomposition of CWD may have significantly …

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