Search Results (5)

Ecological corridors are effective strategies to address the environmental consequences of forest fragmentation by connecting fragmented areas through various techniques. This study aims to propose the implementation of an ecological corridor in the Itapemirim River basin in Espírito Santo, Brazil. The specific objectives of this study are as follows: delimiting the Permanent Preservation Areas (APPs) in the Itapemirim River watershed and comparing land use and land cover within these areas. The MapBiomas platform and Landsat 8 satellite images were utilized to map land use and land cover, while the criteria set by Law No. 12.651 were followed to define the APP boundaries. The calculation of the landscape ecology indices and the identification of the forest fragments with the highest potential for ecological corridor implementation were conducted using the Fuzzy logic. The QGIS 3.26 application, along with the LecoS 3.0.1 plugin and Fragstats 4.2, were employed to characterize and quantify landscape ecology indices. The costs assessment and determination of the optimal route for implementing the ecological corridor were performed, considering bothdistance and physical impediments. The least cost path algorithm was utilized, taking into account land use and land cover, APP, fragment potential, slope, and subnormal clusters. Evaluating land costs and expropriation expenses required to define the ecological corridor in the study area. The identified forest fragments for inclusion in the ecological corridor were the Caparaó National Park, the Serra das Torres State Natural Monument, and other selected fragments based on the application of Fuzzy logic to landscape ecology indices. The corridor route was determined using the least cost path algorithm, considering various factors. This study revealed that the predominant land use and land cover class in the area is pasture, and a significant portion (68.58%) of the designated Permanent Preservation Areas were in conflict with legal regulations. The bare land value per hectare for pasture was the second highest among the land use and land cover categories, accounting for 64.28% of the total. The priority area analysis indicated that 31.86% of the region had high or very high importance for forest restoration, while 42.97% had low or very low priority. The findings demonstrate that the least cost path algorithm, coupled with a multi-criteria decision-making approach using the Analytic Hierarchy Process (AHP), is a valuable tool for planning and implementing ecological networks. These methods effectively consider critical factors in decision-making processes related to the optimal location of the ecological corridor. In conclusion, this study provides insights into the implementation of an ecological corridor in the Itapemirim River basin, emphasizing the importance of considering multiple factors and utilizing appropriate methodologies for effective decision-making in ecological planning. Full article

Mercury is a metal present in the Earth’s crust, but due to human contribution, its concentration can increase, causing environmental impacts to aquatic ecosystems, among others. The Reis Magos River Hydrographic Basin represents economic and socio-environmental importance for the state of Espírito Santo, Brazil. However, there are not many publications regarding the quality of water and sediments, so no data is reported concerning the total concentration of Hg. Thus, the present work aimed to evaluate the distribution of total Hg in water and sediments along this hydrographic basin. For a better inference, physicochemical parameters of the water were determined (temperature, pH, electrical conductivity, oxidation-reduction potential (ORP), turbidity, dissolved oxygen (DO), total dissolved solids (TDS), and salinity), and in the sediments, the contents of matter organic matter, pH, carbonates and granulometry. Mercury determination was performed by Thermodecomposition and Amalgamation Atomic Absorption Spectrometry (TDA AAS) with a DMA-80 spectrometer. The Hg determined in the water was lower than the limit of quantification, 0.14 µg∙L⁻¹, which is lower than the maximum limits recommended by world reference environmental agencies. In the sediment samples, the Hg found were below 170 µg∙kg⁻¹, values below which there is less possibility of an adverse effect on the biota. However, when the degree of anthropic contribution was evaluated using the Geoaccumulation index (IGeo), the contamination factor (CF), and the ecological risk potential index (E_F), there was evidence of moderate pollution. Thus, this highlighted the need for monitoring the region since climatic variations and physical-chemical parameters influence the redistribution of Hg between the water/sediment interface. Full article

The oceanic anoxic events (OAEs) are characterized by enhanced accumulation of organic matter in marine sediments. However, there is still an ongoing debate regarding the interplay between production and preservation during these events. Moreover, few studies provide quantitative estimations of primary productivity and/or the amount of carbon preserved during the OAEs. Here, we used geochemical data from multiple wells located at the Espírito Santo Basin that cover the intervals of events OAE1d and OAE2 to provide quantitative estimates of preservation factors. Our results show enhanced preservation during OAEs compared to modern conditions and a stronger preservation during OAE1d compared to OAE2 in the Espírito Santo Basin. The amount of preserved carbon could reach up to 8.6% during OAE1d, depending on the productivity of the system. In addition, we show that such improvement in preservation is linked to the bottom water with low-O₂ concentrations and not due to fast burial caused by high sedimentation rates. Our findings are extremally relevant for organic carbon and source rock modelling studies since model simulations need quantitative estimations. Full article

A better understanding of deep-sea biology requires knowledge of the structure and function of their communities, the spatial, temporal, and environmental patterns, and the changes and dynamics that govern them. Some of the most studied patterns in deep-sea biology are those related to bathymetrical gradients. For meiofauna and nematodes, such studies have highlighted the importance of recognizing regional differences in using ecological mechanisms to explain those patterns. Despite holding significant fisheries and oil and gas resources, the eastern Brazilian Continental Margin is poorly understood with respect to its seafloor biology and ecology. To answer ecological questions of deep-sea infaunal structural and functional diversity in relation to bathymetrical patterns, we used nematode data from five bathymetric transects (400, 1000, 1900, 2500, and 3000 m water depth) sampled in 2011 and 2013 on the Espírito Santo slope off the coast of southeast (SE) Brazil. Deep nematode community analysis based on 6763 nematode identifications showed very high levels of diversity (201 genera; 43 families) compared to other ocean basins and deep-sea regions. Our analyses showed that there is a distinct bathymetric break in standing stocks and community structure between 1000 and 1900 m. Nematode standing stocks were much higher at 400 and 1000 m compared to those for similar depths worldwide, likely linked to the intense and frequent upwelling and specific hydrographic and topographic identity of the region. The bathymetric break was not present for structural and functional nematode diversity. Instead, bathymetric regressions showed that they increased gradually toward 3000 m water depth. The deep Espírito Santo basin is characterized by rich and equitable nematode communities that are both mature and trophically diverse. General deep-sea ecological theories apply to our findings, but there are also substantial regional effects related to the local margin topography, upwelling, and oceanographic and hydrodynamic processes that make the Espírito Santo Basin a unique and diverse deep-sea ecosystem. Full article

Understanding sediment dynamics in peri-urban catchments constitutes a research challenge because of the spatiotemporal complexity and variability of land-uses involved. This study investigates differences in the concentration of total sediments (TSC) and suspended sediments (SSC) in the small peri-urban Mediterranean Ribeira dos Covões catchment (40% urban area) in central Portugal. Suspended sediment responses at the catchment outlet (E) and in three upstream sub-catchments, during periods of urbanization (2011–2013) and stabilizing land-use (2017–2018) are compared for storm-event datasets encompassing similar ranges of rainstorm sizes and antecedent rainfall condition. The Quinta sub-catchment, with the lowest urban area (22%) but subject to major construction activities affecting 17% of its area, led to highest TSC and SSC during urbanization (attaining 4320 mg/L and 4184 mg/L, respectively), and a median reduction of 38% and 69%, respectively, during stabilization. Espírito Santo sub-catchment, with highest urban area (49%) and minor construction activities, displayed similar median TSC in both periods (258–240 mg/L) but highest SSC reduction (76%), highlighting the impact of the anthropogenic disturbance mainly on fine-particle sediments and a good connectivity with the stream. Porto Bordalo sub-catchment, with 39% urban area and subject to the construction of a four-line road covering 1.5% of its area, showed the lowest TSC and SSC concentrations and the lowest median reductions in both periods (31% and 64%, correspondingly), mainly because of the impact of an unplanned retention basin established with soil from the construction site. Overall, median TSC and SSC reduced 14% and 59% at E, from urbanization to stabilization. Information about sediment dynamics should guide stakeholders in establishing strategies to reduce sediment loads and mitigate the impacts on urban aquatic ecosystems. Full article