TY  - JOUR
A1  - Roda-Boluda, Duna C.
A1  - McDonald, Jordan
A1  - Whittaker, Alexander C.
A1  - D'Arcy, Mitchell
T1  - Lithological controls on hillslope sediment supply
BT  - insights from landslide activity and grain size distributions
JF  - Earth surface processes and landforms : the journal of the British Geomorphological Research Group
N2  - The volumes, rates and grain size distributions of sediment supplied from hillslopes represent the initial input of sediment delivered from upland areas and propagated through sediment routing systems. Moreover, hillslope sediment supply has a significant impact on landscape response time to tectonic and climatic perturbations. However, there are very few detailed field studies characterizing hillslope sediment supply as a function of lithology and delivery process. Here, we present new empirical data from tectonically-active areas in southern Italy that quantifies how lithology and rock strength control the landslide fluxes and grain size distributions supplied from hillslopes. Landslides are the major source of hillslope sediment supply in this area, and our inventory of similar to 2800 landslides reveals that landslide sediment flux is dominated by small, shallow landslides. We find that lithology and rock strength modulate the abundance of steep slopes and landslides, and the distribution of landslide sizes. Outcrop-scale rock strength also controls the grain sizes supplied by bedrock weathering, and influences the degree of coarsening of landslide supply with respect to weathering supply. Finally, we show that hillslope sediment supply largely determines the grain sizes of fluvial export, from catchments and that catchments with greater long-term landslide rates deliver coarser material. Therefore, our results demonstrate a dual control of lithology on hillslope sediment supply, by modulating both the sediment fluxes from landslides and the grain sizes supplied by hillslopes to the fluvial system.
KW  - lithology
KW  - hillslopes
KW  - landslides
KW  - grain size
KW  - sediment supply
Y1  - 2018
U6  - https://doi.org/10.1002/esp.4281
SN  - 0197-9337
SN  - 1096-9837
VL  - 43
IS  - 5
SP  - 956
EP  - 977
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Jones, Geraint H.
A1  - Arridge, Christopher S.
A1  - Coates, Andrew J.
A1  - Lewis, Gethyn R.
A1  - Kanani, Sheila
A1  - Wellbrock, Anne
A1  - Young, David T.
A1  - Crary, Frank J.
A1  - Tokar, Robert L.
A1  - Wilson, R. J.
A1  - Hill, Thomas W.
A1  - Johnson, Robert E.
A1  - Mitchell, Donald G.
A1  - Schmidt, Jürgen
A1  - Kempf, Sascha
A1  - Beckmann, Uwe
A1  - Russell, Christopher T.
A1  - Jia, Y. D.
A1  - Dougherty, Michele K.
A1  - Waite, J. Hunter
A1  - Magee, Brian A.
T1  - Fine jet structure of electrically charged grains in Enceladus' plume
N2  - By traversing the plume erupting from high southern latitudes on Saturn's moon Enceladus, Cassini orbiter instruments can directly sample the material therein. Cassini Plasma Spectrometer, CAPS, data show that a major plume component comprises previously-undetected particles of nanometer scales and larger that bridge the mass gap between previously observed gaseous species and solid icy grains. This population is electrically charged both negative and positive, indicating that subsurface triboelectric charging, i.e., contact electrification of condensed plume material may occur through mutual collisions within vents. The electric field of Saturn's magnetosphere controls the jets' morphologies, separating particles according to mass and charge. Fine-scale structuring of these particles' spatial distribution correlates with discrete plume jets' sources, and reveals locations of other possible active regions. The observed plume population likely forms a major component of high velocity nanometer particle streams detected outside Saturn's magnetosphere.
Y1  - 2009
UR  - http://www.agu.org/journals/gl/
U6  - https://doi.org/10.1029/2009gl038284
SN  - 0094-8276
ER  - 
TY  - JOUR
A1  - De Frenne, Pieter
A1  - Rodriguez-Sanchez, Francisco
A1  - Coomes, David Anthony
A1  - Bäten, Lander
A1  - Versträten, Gorik
A1  - Vellend, Mark
A1  - Bernhardt-Römermann, Markus
A1  - Brown, Carissa D.
A1  - Brunet, Jörg
A1  - Cornelis, Johnny
A1  - Decocq, Guillaume M.
A1  - Dierschke, Hartmut
A1  - Eriksson, Ove
A1  - Gilliam, Frank S.
A1  - Hedl, Radim
A1  - Heinken, Thilo
A1  - Hermy, Martin
A1  - Hommel, Patrick
A1  - Jenkins, Michael A.
A1  - Kelly, Daniel L.
A1  - Kirby, Keith J.
A1  - Mitchell, Fraser J. G.
A1  - Naaf, Tobias
A1  - Newman, Miles
A1  - Peterken, George
A1  - Petrik, Petr
A1  - Schultz, Jan
A1  - Sonnier, Gregory
A1  - Van Calster, Hans
A1  - Waller, Donald M.
A1  - Walther, Gian-Reto
A1  - White, Peter S.
A1  - Woods, Kerry D.
A1  - Wulf, Monika
A1  - Graae, Bente Jessen
A1  - Verheyen, Kris
T1  - Microclimate moderates plant responses to macroclimate warming
JF  - Proceedings of the National Academy of Sciences of the United States of America
N2  - Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., "thermophilization" of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that "climatic lags" may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12-67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass-e.g., for bioenergy-may open forest canopies and accelerate thermophilization of temperate forest biodiversity.
KW  - climate change
KW  - forest management
KW  - understory
KW  - climatic debt
KW  - range shifts
Y1  - 2013
U6  - https://doi.org/10.1073/pnas.1311190110
SN  - 0027-8424
VL  - 110
IS  - 46
SP  - 18561
EP  - 18565
PB  - National Acad. of Sciences
CY  - Washington
ER  - 
TY  - JOUR
A1  - Buratti, Bonnie J.
A1  - Thomas, P. C.
A1  - Roussos, Elias
A1  - Howett, Carly
A1  - Seiss, Martin
A1  - Hendrix, A. R.
A1  - Helfenstein, Paul
A1  - Brown, R. H.
A1  - Clark, R. N.
A1  - Denk, Tilmann
A1  - Filacchione, Gianrico
A1  - Hoffmann, Holger
A1  - Jones, Geraint H.
A1  - Khawaja, N.
A1  - Kollmann, Peter
A1  - Krupp, Norbert
A1  - Lunine, Jonathan
A1  - Momary, T. W.
A1  - Paranicas, Christopher
A1  - Postberg, Frank
A1  - Sachse, Manuel
A1  - Spahn, Frank
A1  - Spencer, John
A1  - Srama, Ralf
A1  - Albin, T.
A1  - Baines, K. H.
A1  - Ciarniello, Mauro
A1  - Economou, Thanasis
A1  - Hsu, Hsiang-Wen
A1  - Kempf, Sascha
A1  - Krimigis, Stamatios M.
A1  - Mitchell, Donald
A1  - Moragas-Klostermeyer, Georg
A1  - Nicholson, Philip D.
A1  - Porco, C. C.
A1  - Rosenberg, Heike
A1  - Simolka, Jonas
A1  - Soderblom, Laurence A.
T1  - Close Cassini flybys of Saturn’s ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus
JF  - Science
N2  - Saturn’s main ring system is associated with a set of small moons that either are embedded within it or interact with the rings to alter their shape and composition. Five close flybys of the moons Pan, Daphnis, Atlas, Pandora, and Epimetheus were performed between December 2016 and April 2017 during the ring-grazing orbits of the Cassini mission. Data on the moons’ morphology, structure, particle environment, and composition were returned, along with images in the ultraviolet and thermal infrared. We find that the optical properties of the moons’ surfaces are determined by two competing processes: contamination by a red material formed in Saturn’s main ring system and accretion of bright icy particles or water vapor from volcanic plumes originating on the moon Enceladus.
Y1  - 2019
U6  - https://doi.org/10.1126/science.aat2349
SN  - 0036-8075
SN  - 1095-9203
VL  - 364
IS  - 6445
SP  - 1053
PB  - American Assoc. for the Advancement of Science
CY  - Washington
ER  -