The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms requi...The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms require an understanding of the role of earthworms in N2O dynamics. We conducted a field experiment to examine the effects of addition of anecic earthworms (Lumbricus terrestris) on N2O flux in a field previously planted with corn (Zea mays) in southern Rhode Island, USA. Plots were amended with (15NH4)2SO4 and either 0 (CTL) or 48 L. terrestris m-2 (EW). The flux of N2O, 15N2O and 15N2 was measured over 28 days between October and November 2008. The EW treatment had a significantly higher flux of N2O and 15N2O 1 - 3 days after 15NH4 addition. No treatment effects were observed on 15N2 flux. The addition of earthworms significantly increased (Day 1) and decreased (Day 12) the mole fraction of N2O relative to the CTL. Our results suggest that anecic earthworm additions can increase N2O flux from inorganic fertilizer N amendments, but the effects appear to short-lived.展开更多
Squeezed quantum vacua seems to violate the averaged null energy conditions (ANEC’s), because they have a negative energy density. When treated as a perfect fluid, rapidly rotating Casimir plates will create vorticit...Squeezed quantum vacua seems to violate the averaged null energy conditions (ANEC’s), because they have a negative energy density. When treated as a perfect fluid, rapidly rotating Casimir plates will create vorticity in the vacuum bounded by them. The geometry resulting from an arbitrarily extended Casimir plates along their axis of rotation is similar to van Stockum spacetime. We observe closed timelike curves (CTC’s) forming in the exterior of the system resulting from frame dragging. The exterior geometry of this system is similar to Kerr geometry, but because of violation of ANEC, the Cauchy horizon lies outside the system unlike Kerr blackholes, giving more emphasis on whether spacetime is multiply connected at the microscopic level.展开更多
文摘The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms require an understanding of the role of earthworms in N2O dynamics. We conducted a field experiment to examine the effects of addition of anecic earthworms (Lumbricus terrestris) on N2O flux in a field previously planted with corn (Zea mays) in southern Rhode Island, USA. Plots were amended with (15NH4)2SO4 and either 0 (CTL) or 48 L. terrestris m-2 (EW). The flux of N2O, 15N2O and 15N2 was measured over 28 days between October and November 2008. The EW treatment had a significantly higher flux of N2O and 15N2O 1 - 3 days after 15NH4 addition. No treatment effects were observed on 15N2 flux. The addition of earthworms significantly increased (Day 1) and decreased (Day 12) the mole fraction of N2O relative to the CTL. Our results suggest that anecic earthworm additions can increase N2O flux from inorganic fertilizer N amendments, but the effects appear to short-lived.
文摘Squeezed quantum vacua seems to violate the averaged null energy conditions (ANEC’s), because they have a negative energy density. When treated as a perfect fluid, rapidly rotating Casimir plates will create vorticity in the vacuum bounded by them. The geometry resulting from an arbitrarily extended Casimir plates along their axis of rotation is similar to van Stockum spacetime. We observe closed timelike curves (CTC’s) forming in the exterior of the system resulting from frame dragging. The exterior geometry of this system is similar to Kerr geometry, but because of violation of ANEC, the Cauchy horizon lies outside the system unlike Kerr blackholes, giving more emphasis on whether spacetime is multiply connected at the microscopic level.
