TY  - JOUR
A1  - Kayler, Zachary E.
A1  - Premke, Katrin
A1  - Gessler, Arthur
A1  - Gessner, Mark O.
A1  - Griebler, Christian
A1  - Hilt, Sabine
A1  - Klemedtsson, Leif
A1  - Kuzyakov, Yakov
A1  - Reichstein, Markus
A1  - Siemens, Jan
A1  - Totsche, Kai-Uwe
A1  - Tranvik, Lars
A1  - Wagner, Annekatrin
A1  - Weitere, Markus
A1  - Grossart, Hans-Peter
T1  - Integrating Aquatic and Terrestrial Perspectives to Improve Insights Into Organic Matter Cycling at the Landscape Scale
JF  - Frontiers in Earth Science
N2  - Across a landscape, aquatic-terrestrial interfaces within and between ecosystems are hotspots of organic matter (OM) mineralization. These interfaces are characterized by sharp spatio-temporal changes in environmental conditions, which affect OM properties and thus control OM mineralization and other transformation processes. Consequently, the extent of OM movement at and across aquatic-terrestrial interfaces is crucial in determining OM turnover and carbon (C) cycling at the landscape scale. Here, we propose expanding current concepts in aquatic and terrestrial ecosystem sciences to comprehensively evaluate OM turnover at the landscape scale. We focus on three main concepts toward explaining OM turnover at the landscape scale: the landscape spatiotemporal context, OM turnover described by priming and ecological stoichiometry, and anthropogenic effects as a disruptor of natural OM transfer magnitudes and pathways. A conceptual framework is introduced that allows for discussing the disparities in spatial and temporal scales of OM transfer, changes in environmental conditions, ecosystem connectivity, and microbial-substrate interactions. The potential relevance of priming effects in both terrestrial and aquatic systems is addressed. For terrestrial systems, we hypothesize that the interplay between the influx of OM, its corresponding elemental composition, and the elemental demand of the microbial communities may alleviate spatial and metabolic thresholds. In comparison, substrate level OM dynamics may be substantially different in aquatic systems due to matrix effects that accentuate the role of abiotic conditions, substrate quality, and microbial community dynamics. We highlight the disproportionate impact anthropogenic activities can have on OM cycling across the landscape. This includes reversing natural OM flows through the landscape, disrupting ecosystem connectivity, and nutrient additions that cascade across the landscape. This knowledge is crucial for a better understanding of OM cycling in a landscape context, in particular since terrestrial and aquatic compartments may respond differently to the ongoing changes in climate, land use, and other anthropogenic interferences.
KW  - landscape connectivity
KW  - organic matter mineralization
KW  - priming effects
KW  - ecological stoichiometry
KW  - aquatic-terrestrial interfaces
KW  - anthropogenic interferences
Y1  - 2019
U6  - https://doi.org/10.3389/feart.2019.00127
SN  - 2296-6463
VL  - 7
PB  - Frontiers Research Foundation
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - van Velzen, Ellen
A1  - Thieser, Tamara
A1  - Berendonk, Thomas U.
A1  - Weitere, Markus
A1  - Gaedke, Ursula
T1  - Inducible defense destabilizes predator–prey dynamics
BT  - the importance of multiple predators
JF  - Oikos
N2  - Phenotypic plasticity in prey can have a dramatic impact on predator-prey dynamics, e.g. by inducible defense against temporally varying levels of predation. Previous work has overwhelmingly shown that this effect is stabilizing: inducible defenses dampen the amplitudes of population oscillations or eliminate them altogether. However, such studies have neglected scenarios where being protected against one predator increases vulnerability to another (incompatible defense). Here we develop a model for such a scenario, using two distinct prey phenotypes and two predator species. Each prey phenotype is defended against one of the predators, and vulnerable to the other. In strong contrast with previous studies on the dynamic effects of plasticity involving a single predator, we find that increasing the level of plasticity consistently destabilizes the system, as measured by the amplitude of oscillations and the coefficients of variation of both total prey and total predator biomasses. We explain this unexpected and seemingly counterintuitive result by showing that plasticity causes synchronization between the two prey phenotypes (and, through this, between the predators), thus increasing the temporal variability in biomass dynamics. These results challenge the common view that plasticity should always have a stabilizing effect on biomass dynamics: adding a single predator-prey interaction to an established model structure gives rise to a system where different mechanisms may be at play, leading to dramatically different outcomes.
KW  - phenotypic plasticity
KW  - inducible defense
KW  - stability
KW  - synchronization
KW  - predator-prey dynamics
Y1  - 2018
U6  - https://doi.org/10.1111/oik.04868
SN  - 0030-1299
SN  - 1600-0706
VL  - 127
IS  - 11
SP  - 1551
EP  - 1562
PB  - Wiley
CY  - Hoboken
ER  -