0000000000288660
AUTHOR
Anthony C. Edwards
Influence of 150 Years of Land Use on Anthropogenic and Natural Carbon Stocks in Emilia-Romagna Region (Italy)
Changes in land use/cover that are commonly associated with urbanization can dramatically influence the amount, chemical form, and spatial distribution of carbon (C) stocks. Measured values and relative literature for composition of natural and anthropogenic materials have been compiled. These data are used in conjunction with land cover statistics and expert assessment of building design to calculate C stocks associated with 150 years of land use change and development for an area of the Po River Valley, Northern Italy. Using 4 time periods (1853, 1954, 1976, and 2003), we demonstrate that the C stocks within this densely populated area have undergone considerable modification. A 52% incre…
Are agricultural soils under a continental temperate climate susceptible to episodic reducing conditions and increased leaching of phosphorus?
International audience; Soil science research has probably underestimated the significance that short-term, episodic cycles of reduction and oxidation has had on phosphorus (P) reactivity. Here, the effects of eleven pulsed reduction-oxidation (including wet-dry) cycles on soil P dynamics are compared for 12 soils having contrasting properties and all overfertilised with respect to P. The laboratory based incubation conditions attempted to simulate transient waterlogging of the soil profile and involved repeated sampling and analysis of both the solution and solid phase P forms. An initial increase in P concentration in solution that occurred up to and including the fourth full cycle was fo…
Simulating soil freeze/thaw cycles typical of winter alpine conditions: Implications for N and P availability
Abstract Seasonally snow-covered alpine soils may be subjected to freeze/thaw cycles, particularly during years having little snow and during the late winter and early spring periods. Freeze/thaw cycles can stimulate soil mineralization and could therefore be one factor regulating nitrogen (N) and phosphorus (P) availability and cycling. In this study laboratory incubation experiments using four soils having contrasting properties have been used to characterize the change in N and P forms (microbial and soluble inorganic/organic) that occur after simulated freeze/thaw cycles. Soil samples were collected from locations representing extreme examples of either direct human management (grazed m…
Phosphorus Loss in Overfertilized Soils: The Selective P Partitioning and Redistribution Between Particle Size Separates
Using 12 well-characterised European soils contrasting in their physical and chemical properties, we demonstrate significant differences in the partitioning of phosphorus (P) between various particle size separates. Samples of each soil were subjected to one of three methods of increasingly aggressive dispersion in the order water (WD), mechanical (MD) or chemical (CD). A general, although not exclusive, inverse relationship existed between the concentration of various attributes (these included organic carbon, oxalate and dithionite iron contents, total P, resin and water extractable P) and particle size. The quantity, composition and physico-chemical properties of individual size separate…
Labile nitrogen, carbon, and phosphorus pools and nitrogen mineralization and immobilization rates at low temperatures in seasonally snow-covered soils
Surface mineral horizons from four ecosystems sampled in the northwestern Italian Alps were incubated at −3 and +3°C to simulate subnivial and early thaw period temperatures for a seasonally snow-covered area. The soil profiles at these sites represent extreme examples of management, grazed meadow (site M) and extensive grazing beneath larch (site L) or naturally disturbed by avalanche and colonized by alder (site A) and the expected forest climax vegetation beneath fir (site F). Changes in labile pools of nitrogen (N) and phosphorus (P) were active at all sites at both temperatures during 14 days of laboratory incubation. Ammonium was the dominant inorganic form of total dissolved N (TDN),…
The influence of pulsed redox conditions on soil phosphorus
Abstract. The effects of eleven pulsed reduction-oxidation cycles (20 and 2 days, respectively) on soil phosphorus (P) dynamics are compared for 12 soils having contrasting properties and overfertilised with respect to P. Incubation conditions simulated transient waterlogging of the soil profile and involved repeated sampling and analysis of both the solution and solid phase P forms. An initial increase in P concentration occurred upto and including the fourth full cycle was followed by a sharp decline in concentration for all but one soil. Accompanying changes in the main extractable forms of P, which appeared to be cumulative, could be summarised as a general decline in the organic P frac…
Changes in the seasonal snow cover of alpine regions and its effect on soil processes: A review
Abstract At its maximum annual development, snow can cover more than half the Northern Hemisphere land area with one-third experiencing seasonal snow cover. The precise conditions that develop during the annual pattern of snowpack development formation have implications for: (i) soil microbiological activity and nutrient transformations; (ii) the capacity of the accumulating snowpack to retain atmospheric derived solutes; (iii) preferential elution and rapid runoff of solutes from the snowpack during periods of thaw; and (iv) leaching of solutes. Long-term records of annual snow accumulation suggest that substantial, regional scale shifts in snowpack characteristics have been occurring. The…