14 research outputs found
Reconstruction of the eruptive history of Usu volcano, Hokkaido, Japan, inferred from petrological correlation between tephras and dome lavas
Usu volcano has erupted nine times since 1663. Most eruptive events started with an explosive eruption, which was followed by the formation of lava domes. However, the ages of several summit lava domes and craters remain uncertain. The petrological features of tephra deposits erupted from 1663 to 1853 are known to change systematically. In this study, we correlated lavas with tephras under the assumption that lava and tephra samples from the same event would have similar petrological features. Although the initial explosive eruption in 1663 was not accompanied by lava effusion, lava dome or cryptodome formation was associated with subsequent explosive eruptions. We inferred the location of the vent associated with each event from the location of the associated lava dome and the pyroclastic flow deposit distribution and found that the position of the active vent within the summit caldera differed for each eruption from the late 17th through the 19th century. Moreover, we identified a previously unrecognized lava dome produced by a late 17th century eruption; this dome was largely destroyed by an explosive eruption in 1822 and was replaced by a new lava dome during a later stage of the 1822 event at nearly the same place as the destroyed dome. This new interpretation of the sequence of events is consistent with historical sketches and documents. Our results show that petrological correlation, together with geological evidence, is useful not only for reconstructing volcanic eruption sequences but also for gaining insight into future potential disasters
Using Light to Improve Commercial Value
The plasticity of plant morphology has evolved to maximize reproductive fitness in response to prevailing environmental conditions. Leaf architecture elaborates to maximize light harvesting, while the transition to flowering can either be accelerated or delayed to improve an individual's fitness. One of the most important environmental signals is light, with plants using light for both photosynthesis and as an environmental signal. Plants perceive different wavelengths of light using distinct photoreceptors. Recent advances in LED technology now enable light quality to be manipulated at a commercial scale, and as such opportunities now exist to take advantage of plants' developmental plasticity to enhance crop yield and quality through precise manipulation of a crops' lighting regime. This review will discuss how plants perceive and respond to light, and consider how these specific signaling pathways can be manipulated to improve crop yield and quality
Reconstruction of the eruptive history of Usu volcano, Hokkaido, Japan, inferred from petrological correlation between tephras and dome lavas
Anthocyanin accumulation and related gene expression affected by low temperature during strawberry coloration
The involvement of PybZIPa in light-induced anthocyanin accumulation via the activation of PyUFGT through binding to tandem G-boxes in its promoter
Blue Light Irradiation Affects Anthocyanin Content and Enzyme Activities Involved in Postharvest Strawberry Fruit
Identification of basic/helix-loop-helix transcription factors reveals candidate genes involved in anthocyanin biosynthesis from the strawberry white-flesh mutant
Modification of sunlight radiation through colored photo-selective nets affects anthocyanin profile in Vaccinium spp. berries
Objectives
In recent years, the interest on the effects of the specific wavelengths of the light spectrum
on growth and metabolism of plants has been increasing markedly. The present study covers
the effect of modified sunlight conditions on the accumulation of anthocyanin pigments
in two Vaccinium species: the European wild bilberry (V. myrtillus L.) and the cultivated highbush
blueberry (V. corymbosum L.).
Methods
The two Vaccinium species were grown in the same test field in the Alps of Trentino (Northern
Italy) under modified light environment. The modification of sunlight radiation was carried
out in field, through the use of colored photo-selective nets throughout the berry
ripening during two consecutive growing seasons. The anthocyanin profile was then
assessed in berries at ripeness.
Results
The results indicated that the light responses of the two Vaccinium species studied were different.
Although both studied species are shade-adapted plants, 90% shading of sunlight
radiation was beneficial only for bilberry plants, which accumulated the highest content of
anthocyanins in both seasons. The same condition, instead, was not favorable for blueberries,
whose maturation was delayed for at least two weeks, and anthocyanin accumulation
was significantly decreased compared to berries grown under sunlight conditions. Moreover,
the growing season had strong influence on the anthocyanin accumulation in both
species, in relation to temperature flow and sunlight spectra composition during the berry
ripening period.
Conclusions
Our results suggest that the use of colored photo-selective nets may be a complementary
agricultural practice for cultivation of Vaccinium species. However, further studies are
needed to analyze the effect of the light spectra modifications to other nutritional properties,
and to elucidate the molecular mechanisms behind the detected differences between the
two relative Vaccinium species