Accelerated release of carbon from soils is one
of the most important feedbacks related to anthropogenically
induced climate change. Studies addressing the mechanisms
for soil carbon release through organic matter decomposition
have focused on the effect of changes in the average temperature,
with little attention to changes in temperature variability....
Calcium oxalate (Ca oxalate) is an insoluble biomineral that forms in plants and fungi, and occurs in soils
across many types of ecosystems. Assessing how Ca oxalate may shape ecosystem Ca cycling requires
information on the distribution of Ca oxalate among plant biomass, detritus, and mineral soil, and how
it...
Acid deposition and repeated biomass harvest have decreased
soil calcium (Ca) availability in many temperate forests worldwide, yet
existing methods for assessing available soil Ca do not fully characterize
soil Ca forms. To account for discrepancies in ecosystem Ca budgets, it
has been hypothesized that the highly insoluble biomineral Ca...
Symbiotic N₂-fixing tree species can accelerate ecosystem N dynamics through decomposition feedbacks via both direct and indirect pathways. Direct pathways include the production of readily decomposed leaf litter and increased N supply to decomposers, whereas indirect pathways include increased tissue N and altered detrital dynamics of non-fixing vegetation. To evaluate...
Full Text:
Accelerates Ecosystem
Nitrogen Cycling
Steven S. Perakis,1* Joselin J. Matkins,2,3 David E. Hibbs,2
and
Symbiotic N₂-fixing tree species can accelerate ecosystem N dynamics through decomposition feedbacks via both direct and indirect pathways. Direct pathways include the production of readily decomposed leaf litter and increased N supply to decomposers, whereas indirect pathways include increased tissue N and altered detrital dynamics of non-fixing vegetation. To evaluate...
Full Text:
Nitrogen
Cycling
Steven S. Perakis,1* Joselin J. Matkins,2,3 and David E. Hibbs2
1U.S. Geological Survey
Studies of nutrient limitation in Douglas-fir forests of the Pacific Northwest focus predominantly on nitrogen, yet many stands demonstrate negligible or even negative growth response to nitrogen fertilization. To understand what nutrients other than nitrogen may limit forest productivity in this region, we tested six fertilizer treatments for their ability...
Riparian-zone vegetation can influence terrestrial and aquatic food webs through variation in the amount, timing, and nutritional content of leaf and other litter inputs. We investigated how riparianforest community composition, understory density, and lateral slope shaped vertical and lateral litter inputs to 16 streams in the Oregon Coast Range. Riparian...
Symbiotic N₂-fixing tree species can accelerate ecosystem N dynamics through decomposition feedbacks via both direct and indirect pathways. Direct pathways include the production of readily decomposed leaf litter and increased N supply to decomposers, whereas indirect pathways include increased tissue N and altered detrital dynamics of non-fixing vegetation. To evaluate...
Soil organic matter is a complex mixture of material with heterogeneous biological, physical, and chemical properties. Decomposition models represent this heterogeneity either as a set of discrete pools with different residence times or as a continuum of qualities. It is unclear though, whether these two different approaches yield comparable predictions...
Annual grass invasion into shrub-dominated ecosystems is associated with changes in nutrient cycling that may alter nitrogen (N) limitation and retention. Carbon (C) applications that reduce plant-available N have been suggested to give native perennial vegetation a competitive advantage over exotic annual grasses, but plant community and N retention responses...