Abstract. Some effects in the biosphere from the Total Solar Eclipse of 29 March 2006 were investigated in field crops and marine zooplankton. Taking into account the decisive role of light on plant life and productivity, measurements of photosynthesis and stomatal behaviour were conducted on seven important field-grown cereal and leguminous crops. A drop in photosynthetic rates, by more than a factor of 5 in some cases, was observed, and the minimum values of photosynthetic rates ranged between 3.13 and 10.13 µmol CO 2 m −2 s −1 . The drop in solar irradiance and the increase in mesophyll CO 2 -concentration during the eclipse did not induce stomatal closure thus not blocking CO 2 uptake by plants. Light effects on the photochemical phase of photosynthesis may be responsible for the observed depression in photosynthetic rates. Field studies addressing the migratory responses of marine zooplankton (microzooplankton (ciliates), and meso-zooplankton) due to the rapid changes in underwater light intensity were also performed. The light intensity attenuation was simulated with the use of accurate underwater radiative transfer modeling techniques. Ciliates, responded to the rapid decrease in light intensity during the eclipse adopting night-time behaviour. From the meso-zooplankton assemblage, various vertical migratory behaviours were adopted by different species.

Halophytes constitute an indispensable part of seawater farming systems implemented in coastal areas of desert lands where they do not compete with good quality land and water resources. Salicornia bigelovii is considered one of the most promising halophytic species that can grow in a biosaline context. However, suitable germplasm needs to be identified, domesticated and improved in order to achieve high yields to compete economically to conventional crops. In the current study, eleven S. bigelovii Torr. populations were evaluated for 22 growth parameters and irrigated with full-strength seawater (SW≈55 dS/m).The study assessed the adaptability of such plant material under the hot and dry climatic conditions that prevail in the Arabian Peninsula. High variation was observed among S. bigelovii populations for most of the characteristics under study. S. bigelovii genotypes were categorized in four groups based on their growth performance and use: for seed production, green biomass as vegetables for human consumption, and biomass as livestock feed; the fourth category was comprised of those halophytic genotypes that demonstrated poor overall performance. Pearson correlation analysis highlighted positive and negative associations among the growth parameters. Path analysis unveiled some interesting interrelationships among growth parameters that could be used for further selection to increase seed production such as number of seeds per spike, number of branches, days to flowering and duration of seed maturity. Plant height and growth cycle could be selected for biomass improvement. The multivariate statistical analyses applied in this study, i.e. clustering, correlation and path analyses were very effective in classifying S. bigelovii genotypes and revealed interrelationships among growth traits that could be selected towards S. bigelovii improvement in terms of seed and biomass yield.

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Archaeological sites of the Mediterranean region are widely colonized by weed species causing various problems both to the monuments and the functionality of the sites. Due to recent regulatory restrictions for herbicide use at archaeological sites, flame weeding was studied as an alternative weed management method. The objective of the study was to test two propane doses (99 kg ha−1 and 129 kg ha−1) applied two, three, or four times at three archaeological sites of Greece (Kolona, Ancient Messene and Early Christian Amfipolis). Percent weed control and weed heights were significantly affected by flaming treatments. Visual evaluation of percent weed control suggested that the propane dose of 129 kg ha−1 applied four times provided excellent weed control (>90%) for over 2 months. Annual broadleaf weeds were controlled better with flaming than grasses and perennial broadleaf species. The high propane dose applied four times reduced average vegetation height to about 10 cm, which was the desirable vegetation height wanted by the managers of the archeological sites suggesting that flame weeding has the potential to be used effectively for weed management in archaeological sites of the Mediterranean region.

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