Authors:
Sivan Golan
, Tomer Faraj
, Erez Rahamim
, Hanita Zemach
, Dikla Lifshitz
, Alon Singer
,
Dana Bar
, Dafna Carmeli, Yosef Steinberger
, Chen Sherman
, Einav Mayzlish Gati |
Abstract:
Long and short-term effects of soil contamination by of Petroleum hydrocarbons spills that
occurred in 1975 and 2014 in a hyper-arid desert in the Arava Valley, Israel, were studied by
assessing soil toxicity on seed germination, and seedling survival of wild local species (Acacia
raddiana Savi, Rumex cyprius Murb., Malva parviflora L. and Astragalus eremophilus Boiss.)
and. cultivated crops (Cucumber-Cucumis sativus, Tomato-Solanum lycopersicum, and PepperCapsicum
annuum). Seed size and seed-coat structure strongly affected germination ability to
soil contaminated with petroleum hydrocarbons in both the old (1975) and new (2014) spill.
Species seeds with thick seed-coat and well developed macrosclereid cells were more tolerant to
contamination than species with thin seed-coat and without macrosclereid cells. Furthermore,
soils containing high were more toxic than soil containing low amounts of volatile compounds
(old spill). Seedlings survival and morphology was strongly affected by the contamination in
both old and new spill, and was leading to dwarf plants with few leaves and high mortality rate
of the seedlings. We strongly recommend that actions to rehabilitate this hyper-arid ecosystem
should take into consideration long term effects of oil spills that constrain the recovery of the
native vegetation across time. |
