TY  - JOUR
A1  - Letawe, G.
A1  - Courbin, F.
A1  - Magain, P.
A1  - Hilker, M.
A1  - Jablonka, P.
A1  - Jahnke, Knud
A1  - Wisotzki, Lutz
T1  - On-axis spectroscopy of the z=0.144 radio-loud quasar HE 1434-1600 : an elliptical host with a highly ionized ISM
N2  - VLT on-axis optical spectroscopy of the z = 0.144 radio-loud quasar HE 1434-1600 is presented. The spatially resolved spectra of the host galaxy are deconvolved and separated from those of the central quasar in order to study the dynamics of the stars and gas as well as the physical conditions of the ISM. We find that the host of HE 1434-1600 is an elliptical galaxy that resides in a group of at least 5 member galaxies, and that most likely experienced a recent collision with its nearest companion. Compared with other quasar host galaxies, HE 1434-1600 has a highly ionized ISM. The ionization state corresponds to that of typical Seyferts, but the ionized regions are not distributed in a homogeneous way around the QSO, and are located preferentially several kiloparsecs away from it. While the stellar absorption lines do not show any significant velocity field, the gas emission lines do. The observed gas velocity field is hard to reconcile with dynamical models involving rotating disk. modified Hubble laws or power laws, that all require extreme central masses (M > 10(9) M-circle dot) to provide only poor fit to the data. Power law models, which best fit the data, provide a total mass of M(<10 kpc) = 9.2 x 10(10) M-&ODOT;. We conclude that the recent interaction between HE 1434-1600 and its closest companion has strongly affected the gas velocity and ionization state, from the center of the galaxy to its most external parts
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Heger, Tina
A1  - Bernard-Verdier, Maud
A1  - Gessler, Arthur
A1  - Greenwood, Alex D.
A1  - Grossart, Hans-Peter
A1  - Hilker, Monika
A1  - Keinath, Silvia
A1  - Kowarik, Ingo
A1  - Küffer, Christoph
A1  - Marquard, Elisabeth
A1  - Mueller, Johannes
A1  - Niemeier, Stephanie
A1  - Onandia, Gabriela
A1  - Petermann, Jana S.
A1  - Rillig, Matthias C.
A1  - Rodel, Mark-Oliver
A1  - Saul, Wolf-Christian
A1  - Schittko, Conrad
A1  - Tockner, Klement
A1  - Joshi, Jasmin Radha
A1  - Jeschke, Jonathan M.
T1  - Towards an Integrative, Eco-Evolutionary Understanding of Ecological Novelty: Studying and Communicating Interlinked Effects of Global Change
JF  - Bioscience
N2  - Global change has complex eco-evolutionary consequences for organisms and ecosystems, but related concepts (e.g., novel ecosystems) do not cover their full range. Here we propose an umbrella concept of "ecological novelty" comprising (1) a site-specific and (2) an organism-centered, eco-evolutionary perspective. Under this umbrella, complementary options for studying and communicating effects of global change on organisms, ecosystems, and landscapes can be included in a toolbox. This allows researchers to address ecological novelty from different perspectives, e.g., by defining it based on (a) categorical or continuous measures, (b) reference conditions related to sites or organisms, and (c) types of human activities. We suggest striving for a descriptive, non-normative usage of the term "ecological novelty" in science. Normative evaluations and decisions about conservation policies or management are important, but require additional societal processes and engagement with multiple stakeholders.
KW  - Anthropocene
KW  - eco-evolutionary experience
KW  - global change
KW  - novel ecosystems
KW  - shifting baselines
Y1  - 2019
U6  - https://doi.org/10.1093/biosci/biz095
SN  - 0006-3568
SN  - 1525-3244
VL  - 69
IS  - 11
SP  - 888
EP  - 899
PB  - Oxford Univ. Press
CY  - Oxford
ER  -