PDF(Pubmed)
Abstract：
A previously undocumented shallow water hydrothermal field from Sicily (Southern Tyrrhenian Sea, Italy) is here described, based on a multidisciplinary investigation. The field, covering an area of nearly 8000 m2 and a depth from the surface to -5 m, was explored in June 2021 to characterise the main physico-chemical features of the water column, describe the bottom topography and features, and identify the main megabenthic and nektonic species. Twenty sites were investigated to characterise the carbonate system. Values of pH ranged between 7.84 and 8.04, ΩCa between 3.68 and 5.24 and ΩAr from 2.41 to 3.44. Geochemical analyses of hydrothermal gases revealed a dominance of CO2 (98.1%) together with small amounts of oxygen and reactive gases. Helium isotope ratios (R/Ra = 2.51) and δ13CCO2 suggest an inorganic origin of hydrothermal degassing of CO2 and the ascent of heat and deep-seated magmatic fluids to the surface. Visual census of fishes and megabenthos (mainly sessile organisms) allowed the identification of 64 species, four of which are protected by the SPA/BIO Protocol and two by the International Union for Conservation of Nature. The macroalgae Halopteris scoparia and Jania rubens and the sponge Sarcotragus sp. were the dominant taxa in the area, while among fishes Coris julis and Chromis chromis were the most abundant species. This preliminary investigation of San Giorgio vent field suggests that the site could be of interest and suitable for future experimental studies of ocean acidification.
摘要：
来自西西里岛（南部第勒尼安海，意大利)在这里描述，基于多学科调查。场,占地面积近8000平方米，从地表到-5米的深度，2021年6月进行了探索，以表征水柱的主要物理化学特征，描述底部的地形和特征，并确定主要的巨型和内克尼亚物种。研究了20个地点以表征碳酸盐系统。pH值在7.84和8.04之间，ΩCa在3.68和5.24之间，ΩAr在2.41至3.44之间。热液气体的地球化学分析显示，CO2占主导地位（98.1％）以及少量的氧气和反应性气体。氦同位素比（R/Ra=2.51）和δ13CCO2表明CO2的热液脱气以及热量和深层岩浆流体上升到地表的无机起源。对鱼类和巨栖动物（主要是无柄生物）的视觉普查可以鉴定出64种，其中四个受到SPA/BIO议定书的保护，两个受到国际自然保护联盟的保护。大型藻类Halopterisscoparia和Janiarubens和海绵Sarcotragussp。是该地区的主要分类群，而在鱼类中，乔利斯和铬米是最丰富的物种。对SanGiorgio喷口场的初步调查表明，该站点可能会引起人们的兴趣，并适用于未来的海洋酸化实验研究。
