We evaluated nutrient uptake efficiency and subsequent leaching fractions for western white pine (Pinus monticola Dougl. ex D. Don) seedlings grown with exponentially increasing or conventional (constant) fertilization in a greenhouse. Conventional fertilization was associated with higher leachate electrical conductivity and greater nutrient losses, which were more pronounced for the more mobil...

Agricultural terraces are the most widespread archaeological landforms worldwide. Despite their far-reaching prevalence in many inhabited parts of world, soils (hereafter ‘terrace soils’) scarcely studied and nature is poorly defined. This study aims to depict a space–time framework for development calcareous stone-wall bench suggest modifications soil classification mapping. To do so, we exami...

This paper describes the development of a field-scale model that simulates the nitrogen (N) cycle in grazed grassland within a catchment-scale management model which can predict the loading and concentration of nitrate in rivers. The development is comprised of the addition of two sub-models of nitrate transport: one relating the amount of soil nitrate to its concentration in drainage water for...

Nitrogen saturation results in greater mobility of nitrate, which in turn is often correlated with concentrations of nutrient cations in soil solution and streamwater. At the Harvard Forest, U.S.A., under long-term NH4NO3 inputs, a Pinus resinosa Ait. forest has exhibited signs of N saturation more rapidly than a mixed-Quercus forest. We test the hypothesis that increased nitrate leaching cause...

In this study, postfire coarse woody debris (CWD) dynamics in northern Quebec, Canada, were assessed using a 29-year chronosequence. Postfire woody-debris storage, decomposition rates, and variation of nitrogen and carbon contents of black spruce CWD (Picea mariana (Mill.) BSP) are estimated. The decomposition rate for postfire snags is exceptionally slow (k = 0.00), while the decomposition rat...

Soldés par des échecs au cours de la décennie 1950-1960, les essais développement culture attelée en Côte d'Ivoire ont finalement connus une suite heureuse 1971 à 1980 avec mise place 10 000 attelages bovins. Depuis, cette forme mécanisation l’agriculture s’est progressivement répandue dans le Nord d’Ivoire notamment sous-préfecture Sirasso du fait résultats probants qu’elle a enregistrés et l’...

Growth of larvae of the eastern tree-hole mosquito, Aedes triseriatus (Say), measured as survival to adulthood, development time, and body mass at adult emergence, was significantly better when larvae were provided with fresh rather than senescent beech leaves as food substrate. Leaf type affected larval growth performance independently of ration of leaf available per larva when the ration leve...