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Rhodolith beds are one of the main habitats of the Brazilian Equatorial Margin continental shelf due to their wide extent and provision of ecosystem services. Northern, Central and Southern zones of the Amazon River mouth were sampled between water-depths of 23 and 120 m, covering a continental shelf area of 9500 km2, to characterize the structure and composition of rhodoliths along depth gradients and related river plume influence. The deepest rhodoliths consist of a thin algal/bryozoan/encrusting foraminifer cover around relatively large nuclei that determine the nodule size and shape. At 120-m depth in the Northern zone the nuclei are made of fragments of invertebrate boundstone or oolite rudstone, whereas at 100-m depth in the Central zone the nuclei consist of sandstone clasts. In both cases, the nuclei are fragments of sedimentary rocks that accumulated on the outer shelf during significantly lower sea level. Low-light levels prevent substantial growth of the algal cover around the nuclei. Reduced illumination an d high nutrient levels led to the composition of rhodoliths at 95-m depth in the Northern zone, predominantly built by bryozoans with subordinate coralline algae around small bioclastic nuclei. In the Central zone at 50–55 m depths, coralline algae are the main components of mostly sub-spheroidal rhodoliths. They have relatively recent ages of hundreds of years or show two phases of growth with the older phase beginning 1300 years ago and then being interrupted from about 1000 years BP to 600 years BP. All this suggests relatively high burial rates due to sediment flux, changing in time to favor exhumation after burial in some instances. The rhodoliths from 23 m in the Southern zone are growing under a low influence of the river plume and have the highest diversity of coralline algae and other builders. The rhodolith structure in the different sampling zones and depths reflects plume influence on light penetration, nutrient and organic matter levels, and sedimentation on the shelf, determining residence times of rhodoliths on the seafloor before burial.

The abundance of reef builders, non-builders and the calcium carbonate produced by communities established in Calcification Accretion Units (CAUs) were determined in three Abrolhos Bank shallow reefs during the period from 2012 to 2014. In addition, the seawater temperature, the irradiance, and the amount and composition of the sediments were determined. The inner and outer reef arcs were compared. CAUs located on the inner reef shelf were under the influence of terrigenous sediments. On the outer reefs, the sediments were composed primarily of marine biogenic carbonates. The mean carbonate production in shallow reefs of Abrolhos was 579 ± 98 g m-2 y-1. The builder community was dominated by crustose coralline algae, while the non-builder community was dominated by turf. A marine heat wave was detected during the summer of 2013-2014, and the number of consecutive days with a temperature above or below the summer mean was positively correlated with the turf cover increase. The mean carbonate production of the shallow reefs of Abrolhos Bank was greater than the estimated carbonate production measured for artificial structures on several other shallow reefs of the world. The calcimass was higher than the non-calcareous mass, suggesting that the Abrolhos reefs are still in a positive carbonate production balance. Given that marine heat waves produce an increase of turf cover on the shallow reefs of the Abrolhos, a decrease in the cover represented by reef builders and shifting carbonate production are expected in the near future.

Submitted by Thiago de Oliveira Gonzaga (thiago.gonzaga@fjp.mg.gov.br) on 2021-11-29T18:01:14Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Economic environmental management tools in the Serra do Espinhaço biosphere reserve.pdf: 1727466 bytes, checksum: b7972529fe2df18e621a55a4a341e433 (MD5) Approved for entry into archive by Roger Guedes (roger.guedes@fjp.mg.gov.br) on 2021-12-02T01:58:37Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Economic environmental management tools in the Serra do Espinhaço biosphere reserve.pdf: 1727466 bytes, checksum: b7972529fe2df18e621a55a4a341e433 (MD5) Made available in DSpace on 2021-12-02T01:58:37Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Economic environmental management tools in the Serra do Espinhaço biosphere reserve.pdf: 1727466 bytes, checksum: b7972529fe2df18e621a55a4a341e433 (MD5) Previous issue date: 2012 Pontifícia Universidade Católica de Minas Gerais -- Fundação João Pinheiro Pontifícia Universidade Católica de Minas Gerais Universidade Federal de Minas Gerais Governo e Política UNESCO-MAB biosphere reserves are composed of 580 sites distributed in 112 countries. The ecosystems comprising these sites are of global importance because of their biodiversity and endemism levels as well as because of their ecosystem goods and services provided. Biosphere reserves are learning sites for sustainable development. However many of them are threatened because of climate change, land use changes and environmental pollution which cause the degradation of natural resources. In order to mitigate those threats we argue that private and public policies as well as the perception of the value of natural resources by the population should be improved. The objective of the present article is to analyse the application and impacts of economic tools as the payment of ecosystem services in the management of the Serra do Espinhaço Biosphere Reserve. This area was declared biosphere reserve in June 2005, it has 3 076 457.8 ha, which includes 53 municipalities in the state of Minas Gerais (Brazil) with a total population of 3 442 906 inhabitants. Economic tools have been used to revert or compensate the impacts of a large mining exploitation area located in the transition zone of this site. The ecological ICMS (Merchandise and Service Circulation Tax) that provides the municipalities with access to funding resources according to environmental criteria is analysed. Mining is the most important economic activity in the area which is a major user of land and water resources in the region. They compensate the municipalities financially for the extraction of natural resources. Both economic tools, the ecological ICMS and mining royalties, are here proposed as elements to be used to improve the social dialogue process. The decisions related to the financial resources should be considered based on the social dialogue as well as on the scientific and monitoring data. In addition, reinforce the positive effects of the participation of stakeholders.

The marine ecosystems of Todos os Santos Bay (TSB, The State of Bahia, Brazil) have been impacted by the presence on its coast of a large metropolitan area as well as of chemical and petrochemical activities. Despite its ecological importance, there is a lack of scientific information concerning metal contamination in TSB marine biota. Thus, we analyzed concentrations of metals in four species of marine benthic organisms (two seaweeds, Padina gymnospora and Sargassum sp. one seagrass, Halodule wrightii and one oyster, Crassostrea rhizophorae) in three sites from the TSB region that have been most affected by industrial activities. The concentrations of Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined by Atomic Absorption Spectrophometry. The obtained data indicates that cadmium and copper in seaweeds, oysters and seagrass, as well as Ni concentrations in oysters, were in range of contaminated coastal areas. Cadmium and copper are available to organisms through suspended particles, dissolved fraction of water column and bottom sediment interstitial water. As oysters and other mollusks are used as food sources by the local population, the metal levels found in oysters in TSB may constitute a health risk for this population. Our results suggest implanting a heavy metals biomonitoring program in the TSB marine ecosystems.