Use of open-top chambers to study the effect of climate change in aquatic ecosystems

The aim of this research was to explore the possibility to use inexpensive open-top chambers (OTCs) as passive artificial warming devices in experimental aquatic studies. Our results show that OTCs give a significant temperature increase compared with the control. The measured increase (up to an average of 2.3°C) corresponds with predicted climatic warming. Due to their open top, the light quantity and quality is only minimally reduced. We found that OTCs are especially suited for studying the effect of climate change in small waters as the vertical temperature gradients remain unchanged. They can also easily be transported to remote environments. We discuss other advantages and disadvantages of these devices for aquatic studies and compare them with other warming devices

Levisticum officinale hairy root cultures: influence of light and light type on growth and essential oil production

The essential oils of Levisticum officinale W.D.J. Koch (Apiaceae), including those isolated from the roots, are used in the cosmetic, pharmaceutical and food industries [1]. This perennial and herbaceous plant, commonly known as lovage, is widely known by its aromatic, ornamental and medicinal properties. The effect of light and light type on growth and essential oil production of lovage hairy root cultures was studied by comparison of cultures maintained under “blue-basic” (400-550nm) and “day-light” 16h light photoperiod with control cultures maintained under darkness. All cultures were maintained in SH medium [2] and kept at 24ºC on orbital shakers at 80 r.p.m. Growth was evaluated by fresh weight (f.w.), dry weight (d.w.) and by the dissimilation method. The essential oil samples were isolated by distillation-extraction and analysed by GC and GC-MS. Control hairy root cultures showed a fifteen-fold d.w. biomass increase at the end of the growth period (six weeks), whereas an approximately eight-fold and ten-fold increase was obtained with “blue-basic” and “day-light” grown cultures, respectively. These differences were supported by morphological and histochemical analyses. Major changes were detected in the essential oil composition, but Z-falcarinol was in all cases the major oil constituent: in darkness, “day-light” and “blue-basic” grown cultures (75%, 94% and 61%, respectively).FC

Use of open-top chambers to study the effect of climate change in aquatic ecosystems

The aim of this research was to explore the possibility to use inexpensive open-top chambers (OTCs) as passive artificial warming devices in experimental aquatic studies. Our results show that OTCs give a significant temperature increase compared with the control. The measured increase (up to an average of 2.3°C) corresponds with predicted climatic warming. Due to their open top, the light quantity and quality is only minimally reduced. We found that OTCs are especially suited for studying the effect of climate change in small waters as the vertical temperature gradients remain unchanged. They can also easily be transported to remote environments. We discuss other advantages and disadvantages of these devices for aquatic studies and compare them with other warming devices