Depth and water mass zonation and species associations of cold-water octocoral and stony coral communities in the southwestern Atlantic

Abstract

The Southwest Atlantic continental margin between latitudes 21 and 23°S comprises the Campos Basin area. Its continental shelf is some 100 km wide, with the slope starting between 80 and 130 m in depth. The slope is about 40 km wide, extending deeper to the south (2000 m) than to the north (1500 m). Water masses influencing the area include (1) surficial tropical water (TW), 250 to 300 m depth; (2) South Atlantic central water (SACW), below TW 300 to 550 m; (3) Antarctic intermediate water (AIW), between 550 and 1200 m depth; and (4) North Atlantic deep water (NADW), 1200 to 3500 m depth. Distributions of octocorals (25 genera, 32 species/morphotypes) and stony corals (27, 11) and associations among taxa and with water masses were analyzed. Different communities were found over 3 depth ranges. Complete dissimilarity was observed between the continental shelf margin/upper slope and the middle-lower slope. The shallower depth range (52 to 760 m) was influenced by TW, SACW and the upper limit of AIW, while 11 species/morphotypes occurred exclusively in the middle depths (1000 to 1200 m), under the sole influence of AIW. No species were exclusive to the deepest depth range (1200 to 1605 m), which is bathed by NADW. Middle slope areas were distinct from one another, while lower slope areas were more homogeneous. Co-occurrences of species indicate the type of environment they live in, as soft or hard bottoms.

The culturome of the human nose habitats reveals individual bacterial fingerprint patterns

“…In order to assess the co-occurrence nature of species across these samples, a species-similarity matrix was generated using the Bray-Curtis coefficient. Most prevalent species (present in ≥ 5 patients) were clustered using group-average agglomerative hierarchical clustering (Field et al, 1982;Arantes et al, 2009;Bryan, 2010). When the cultivable-fingerprinting method was analysed, the data matrix comprised presence/ absence data (a binary matrix).…”

Chemical and biological aspects of octocorals from the Brazilian coast

“…This deepwater species is found in southern Brazil, in the Campos Basin at depths of 1,059 to 1,114 meters (Arantes et al, 2009). There are no chemical studies on this species, but briarane-type diterpenes, as anthoptilide A, have been isolated from the Australian A. kukenthai (119) (Pham et al, 2000).…”

“…The Brazilian octocoral fauna, particularly deep-sea species, is still poorly known compared to the Caribbean fauna (Arantes et al, 2009;Castro et al, 2010). Around 107 species and/or morphotypes have been reported in Brazilian waters, some only recently.…”

Environmental forcing of the Campeche cold-water coral province, southern Gulf of Mexico

“…North of the Straits of Florida the Florida Current forms 90 % of the Gulf Stream, passing north along the margins of South Carolina and Georgia, from where also large CWC provinces have been reported (Ross, 2007;Ross and Quattrini, 2007;Messing et al, 2008). South of the Campeche CWC province, Lophelia is known from off Brazil, Venezuela and Colombia and was recently mapped off Roatan, Honduras (Reyes et al, 2005;Lutz and Ginsburg, 2007;Arantes et al, 2009;Mangini et al, 2010;Etnoyer et al, 2011), thus following the path of the northward-flowing AAIW that bypasses the Campeche Bank (Merino, 1997). Such an oceanic intermediate water gateway (sensu Henry, 2011) may exert strong control on coral larval dispersal routes as has been documented for Desmophyllum dianthus populations in the South Pacific (Miller et al, 2011).…”