Reservoirs are intrinsically linked to the rivers that feed them, creating a river–reservoir continuum in which water and sediment inputs are a function of the surrounding watershed land use. We examined the spatial and temporal variability of sediment denitrification rates by sampling longitudinally along an agriculturally influenced river–reservoir continuum monthly for 13 months. Sediment de...

presence and activity of denitrifiers. These factors have The effect of NO3--N diffusion on the order and rate of debeen studied bv several workers, for example, Bremner and nitrification reaction was studied in IS soils from various locations in Shaw (1958a, 1958b), Nommik (1956), Patrick (1960), the U.S. The soils were amended with 0.5% rice straw and incubated Broadbent and Clark (1965), and...

OBJECTIVES Sugarcane cultivation is associated with catchment-wide impacts related to application of vinasse, a nutrient-dense effluent with high eutrophication potential. We evaluated the potential for biochar (charcoal produced from pyrolyzed filtercake) to mitigate carbon and nutrient leaching in a cultivated Brazilian Ferralsol after vinasse application. METHODS Twelve soil columns (soil ...

Two objectives of the Common Agricultural Policy post-2013 (CAP, 2014-2020) in the European Union (EU) are the sustainable management of natural resources and climate smart agriculture. To understand the CAP impact on these priorities, the Land Use/Cover statistical Area frame Survey (LUCAS) employs direct field observations and soil sub-sampling across the EU. While a huge amount of informatio...

Denitrification, as an important part of the soil nitrogen cycle, is widely considered to be a major source nitrous oxide (N2O). Both biotic and abiotic denitrification processes contribute significantly N2O emission, especially under acidic conditions. Increasing pH was found suppress emissions from denitrification, while underlying mechanism remains uncertain. In this study, we incubated fres...

The difficulty of measuring gross N2O production and consumption in soil impedes our ability to predict N2O dynamics across the soil-atmosphere interface. Our study aimed to disentangle these processes by comparing measurements from gas-flow soil core (GFSC) and 15N2O pool dilution (15N2OPD) methods. GFSC directly measures soil N2O and N2 fluxes, with their sum as the gross N2O production, wher...

[1] Site preference (SP), the difference in dN between the central and outer nitrogen atoms in N2O, is a powerful approach for apportioning fluxes of N2O from soils to nitrification and denitrification (Sutka et al., 2006). A critical aspect of the use of SP data to apportion sources of N2O to nitrification and denitrification is the need to evaluate data for isotope shifts that may have occurr...

Agricultural soils can constitute either a net source or sink of the three principal greenhouse gases, carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4). We compiled the most up-to-date information available on the contribution of agricultural soils to atmospheric levels of these gases and evaluated the mitigation potential of various management practices in eastern Canada and northe...

[1] Since the early 1980s, water management of rice paddies in China has changed substantially, with midseason drainage gradually replacing continuous flooding. This has provided an opportunity to estimate how a management alternative impacts greenhouse gas emissions at a large regional scale. We integrated a process-based model, DNDC, with a GIS database of paddy area, soil properties, and man...

Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and ...