TY  - JOUR
A1  - Annunziata, Maria Grazia
A1  - Apelt, Federico
A1  - Carillo, Petronia
A1  - Krause, Ursula
A1  - Feil, Regina
A1  - Mengin, Virginie
A1  - Lauxmann, Martin A.
A1  - Koehl, Karin
A1  - Nikoloski, Zoran
A1  - Stitt, Mark
A1  - Lunn, John Edward
T1  - Getting back to nature: a reality check for experiments in controlled environments
JF  - Journal of experimental botany
N2  - Irradiance from sunlight changes in a sinusoidal manner during the day, with irregular fluctuations due to clouds, and light-dark shifts at dawn and dusk are gradual. Experiments in controlled environments typically expose plants to constant irradiance during the day and abrupt light-dark transitions. To compare the effects on metabolism of sunlight versus artificial light regimes, Arabidopsis thaliana plants were grown in a naturally illuminated greenhouse around the vernal equinox, and in controlled environment chambers with a 12-h photoperiod and either constant or sinusoidal light profiles, using either white fluorescent tubes or light-emitting diodes (LEDs) tuned to a sunlight-like spectrum as the light source. Rosettes were sampled throughout a 24-h diurnal cycle for metabolite analysis. The diurnal metabolite profiles revealed that carbon and nitrogen metabolism differed significantly between sunlight and artificial light conditions. The variability of sunlight within and between days could be a factor underlying these differences. Pairwise comparisons of the artificial light sources (fluorescent versus LED) or the light profiles (constant versus sinusoidal) showed much smaller differences. The data indicate that energy-efficient LED lighting is an acceptable alternative to fluorescent lights, but results obtained from plants grown with either type of artificial lighting might not be representative of natural conditions.
KW  - Amino acid
KW  - Arabidopsis thaliana
KW  - controlled environment
KW  - LED lighting
KW  - visible light spectrum
KW  - organic acid
KW  - starch
KW  - sucrose
KW  - trehalose 6-phosphate
Y1  - 2017
U6  - https://doi.org/10.1093/jxb/erx220
SN  - 0022-0957
SN  - 1460-2431
VL  - 68
SP  - 4463
EP  - 4477
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Menzel, Philip
A1  - Gaye, Birgit
A1  - Mishra, Praveen Kumar
A1  - Anoop, Ambili
A1  - Basavaiah, Nathani
A1  - Marwan, Norbert
A1  - Plessen, Birgit
A1  - Prasad, Sushma
A1  - Riedel, Nils
A1  - Stebich, Martina
A1  - Wiesner, Martin G.
T1  - Linking Holocene drying trends from Lonar Lake in monsoonal central India to North Atlantic cooling events
JF  - Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences
N2  - We present the results of biogeochemical and mineralogical analyses on a sediment core that covers the Holocene sedimentation history of the climatically sensitive, closed, saline, and alkaline Lonar Lake in the core monsoon zone in central India. We compare our results of C/N ratios, stable carbon and nitrogen isotopes, grain-size, as well as amino acid derived degradation proxies with climatically sensitive proxies of other records from South Asia and the North Atlantic region. The comparison reveals some more or less contemporaneous climate shifts. At Lonar Lake, a general long term climate transition from wet conditions during the early Holocene to drier conditions during the late Holocene, delineating the insolation curve, can be reconstructed. In addition to the previously identified periods of prolonged drought during 4.6-3.9 and 2.0-0.6 cal ka that have been attributed to temperature changes in the Indo Pacific Warm Pool, several additional phases of shorter term climate alteration superimposed upon the general climate trend can be identified. These correlate with cold phases in the North Atlantic region. The most pronounced climate deteriorations indicated by our data occurred during 62-5.2,4.6-3.9, and 2.0-0.6 cal ka BP. The strong dry phase between 4.6 and 3.9 cal ka BP at Lonar Lake corroborates the hypothesis that severe climate deterioration contributed to the decline of the Indus Civilisation about 3.9 ka BP. (C) 2014 Elsevier B.V. All rights reserved.
KW  - Lake sediment
KW  - Indian monsoon
KW  - Holocene
KW  - Climate reconstruction
KW  - Stable carbon isotope
KW  - Amino acid
Y1  - 2014
U6  - https://doi.org/10.1016/j.palaeo.2014.05.044
SN  - 0031-0182
SN  - 1872-616X
VL  - 410
SP  - 164
EP  - 178
PB  - Elsevier
CY  - Amsterdam
ER  -