scholarly journals Ichthyofauna diversity of Taperoá II reservoir, semi-arid region of Paraíba, Brazil

2012 ◽  
Vol 72 (1) ◽  
pp. 113-120 ◽  
Author(s):  
AKA Montenegro ◽  
JER Torelli ◽  
MC Crispim ◽  
MIM Hernández ◽  
AMA Medeiros
Keyword(s):  
Diversity Index ◽  
Significant Negative Correlation ◽  
Local Economy ◽  
Water Volume ◽  
Degree Of Dominance ◽  
Similarity Indices ◽  
Semi Arid Region ◽  
One Year ◽  
Number Of Individuals ◽  
Semi Arid

To determine the fish species present in Taperoá II Reservoir, and their relevance to the local economy, this research aimed to evaluate the composition, abundance, degree of dominance and constancy of species, along with diversity, richness, evenness and similarity indices in a tropical semi-arid fish assemblage, during one year. Six 24 hour-long samplings were carried out between October 2005 and October 2006 using cast, seine and gillnets. The 889 collected individuals belonged to 11 species from 9 families. Temporal variation was observed in the capture frequency of different species, and a significant negative correlation between precipitation and number of individuals was also observed. Among the recorded families, Characidae showed a higher frequency of occurrence (38.4%), mostly due to Astyanax bimaculatus (Linnaeus, 1758) and A. fasciatus (Cuvier, 1819). Eight species were categorised as constant, two as accessory and one as accidental. Diversity index values were intermediate with low fluctuation throughout the study period, and no correlation with precipitation or water volume. However, the greatest diversity value was recorded in March 2006, when the peak of the precipitation was recorded. Evenness values showed a similar trend to the diversity index.

scholarly journals Diversity and structure of microcrustacean assemblages (Cladocera and Copepoda) and limnological variability in perennial and intermittent pools in a semi-arid region, Bahia, Brazil

2011 ◽  
Vol 101 (4) ◽  
pp. 317-324 ◽  
Author(s):  
Nadson R. Simões ◽  
Sylvia M. M. S. Ribeiro ◽  
Sérgio L. Sonoda
Keyword(s):  
Electrical Conductivity ◽  
Arid Region ◽  
Suspended Solids ◽  
Diversity Index ◽  
Total Alkalinity ◽  
Water Volume ◽  
Aquatic Environments ◽  
Physical Factors ◽  
Semi Arid Region ◽  
Semi Arid

Temporary wetlands undergo recurrent drought due to the scarcity of water, which disrupts the hydrological connectivity with adjacent aquatic systems. However, some environments retain water for longer periods, allowing greater persistence of the community. The current study evaluated differences in the microcrustacean assemblages and limnological variability between perennial and intermittent pools in a semi-arid region of Brazil. The abiotic features (water temperature, pH, total alkalinity, electrical conductivity and depth) of intermittent pools were affected more than perennial pools due to loss of water volume. This may have contributed to a higher average richness and diversity index in some intermittent pools and differences in the structure of the assemblages. The lowest species richness and diversity were recorded where physical factors, such as a large quantity of suspended solids and variability in the electrical conductivity of the water and pH, make the environment unsuitable for these organisms. These results suggest that community development in intermittent pools is interrupted by the dry season; when the water returns, due to rainfall or rising groundwater, each pond undergoes a different process of colonization. In these circumstances, the biological importance of temporary aquatic environments is clear, since such pools provide shelters and have an important role in the maintenance of the regional diversity of aquatic environments.

scholarly journals Land degradation trend assessment over Iberia during 1982-2012

2016 ◽  
Vol 42 (1) ◽  
pp. 89 ◽  
Author(s):  
C.M. Gouveia ◽  
P. Páscoa ◽  
A. Russo ◽  
R.M. Trigo
Keyword(s):  
Land Cover ◽  
Land Degradation ◽  
Ipcc Report ◽  
Change Context ◽  
Hydrological Stress ◽  
Trend Assessment ◽  
Semi Arid Region ◽  
One Year ◽  
Land Improvement ◽  
Semi Arid

Land degradation is recognized as an important environmental and social problem in arid and semi-arid regions, particularly within a climate change context. In the last three decades the entire Mediterranean basin has been affected by more frequent droughts, covering large sectors and often lasting more than one year. The Iberian Peninsula has been equally affected by intense drought events since the 1980s. According to the latest IPCC report the Mediterranean region will suffer further hydrological stress in the coming decades, as a consequence of diminishing of precipitation and increasing of average and extreme temperatures. This climatic outlook coupled with the land abandonment and/or intensification of some areas requires a continuous monitoring and early detection of degradation. The present work intends to contribute to such objectives.Land degradation could be stated as a longstanding deterioration in ecosystems productivity. Here we assess the ability of NDVI to be used as an indicator of land degradation over Iberia, from 1982 to 2012. The negative trends of the residuals obtained after removing the precipitation influence on NDVI were assumed to indicate land degradation. A widespread land improvement was observed over Iberia with few hot spots of land degradation located mainly in central and southern sectors and in east Mediterranean and Atlantic coasts. The comparison of spatial patterns of residual trends with dryness for the aridity regions over Iberia highlighted the relatively small fraction of land degradation that experiences an increased dryness, although almost totality belonging to semi-arid region. On the other hand, land improvement is only associated with a tendency of wetness in the northeastern humid sector. Moreover, less than 20% of the area presenting land degradation corresponds to regions associated with land cover changes, being the new land cover types associated with transitional woodland-shrub, permanent and annual crops and permanently irrigated land areas.

scholarly journals Extreme droughts drive tropical semi-arid eutrophic reservoirs towards CO2 sub-saturation

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Jurandir Rodrigues de Mendonça Júnior ◽  
André Megali Amado ◽  
Luciana de Oliveira Vidal ◽  
Arthur Mattos ◽  
Vanessa Becker
Keyword(s):  
Carbon Dioxide ◽  
Water Level ◽  
Chlorophyll A ◽  
Co2 Reduction ◽  
Water Volume ◽  
Drought Period ◽  
Autotrophic Metabolism ◽  
Semi Arid Region ◽  
Carbon Dioxide Co2 ◽  
Semi Arid

Abstract Aim: This study aimed to evaluate the carbon dioxide (CO2) dynamics in tropical semi-arid reservoirs during a prolonged drought period as well as to test if the trophic state affects the CO2 saturation. Methods This study was performed in four reservoirs located in the tropical semi-arid region in the northeast of Brazil. All samplings were performed between 9 and 12 am using a Van Dorn Bottle. Samples for partial pressure of carbon dioxide (pCO2 ) measurements were taken in the sub-surface as well as samples for total phosphorus and chlorophyll-a. Correlation analysis and linear regression were used to detect relations among the calculated pCO2, water volume and chlorophyll-a. Results The water level reduction due to atypical droughts caused chlorophyll-a concentrations to increase, which in turn, led to CO2 reduction in the water. However, CO2 concentrations were very variable and an alternation between CO2 sub-saturation and super-saturation conditions was observed. This paper showed that water volume and chlorophyll-a were important regulators of CO2 in the water, as well as important carbon balance predictors in the tropical semiarid reservoirs. Conclusions The results of this paper indicate that the eutrophication allied to drastic water level reductions lead to a tendency of autotrophic metabolism of these systems.

scholarly journals Macrofauna inhabiting the sponge Paraleucilla magna (Porifera: Calcarea) in Rio de Janeiro, Brazil

2013 ◽  
Vol 93 (4) ◽  
pp. 889-898 ◽  
Author(s):  
André Padua ◽  
Emilio Lanna ◽  
Michelle Klautau
Keyword(s):  
Community Composition ◽  
Rio De Janeiro ◽  
Native Species ◽  
Diversity Index ◽  
Marine Fauna ◽  
Pregnant Females ◽  
Animal Phyla ◽  
Previous Proposal ◽  
One Year ◽  
Number Of Individuals

Sponges (phylum Porifera) are important components of the benthic marine fauna known for their interactions with vertebrates and a large number of invertebrates seeking for food, shelter or substrate for attachment. Studies on this subject, however, were restricted only to the macrofauna inhabiting sponges of the class Demospongiae. In the present work, we describe the macrofauna associated with a calcareous sponge in Brazil, Paraleucilla magna. Individuals of this allegedly non-native species were monthly collected during one year in Rio de Janeiro (Brazil). Fifty-one taxa representing ten animal phyla were found associated with P. magna. The most frequent and abundant taxa were Crustacea, Mollusca, Polychaeta and Bryozoa, while echinoderms, cnidarians, ascidians, nemerteans, platyhelminthes and sponges were less frequent or even rare and less abundant. Juveniles of several taxa and pregnant females of Crustacea were found associated with P. magna, but these associations were not exclusive. The macrofauna associated with P. magna did not present a clear seasonality, although it was possible to observe a change in the community composition alongside the year. The volume of the sponges was significantly related to the diversity index (H′) and number of taxa, but not with evenness (J′) and number of individuals. Our results show that P. magna is used as a substrate for attachment and/or shelter by its associates and that most of these associations are just opportunistic. The data presented here reiterate a previous proposal that sponges are important biodiversity reservoirs and that they should be seriously considered in conservation programmes.

scholarly journals Effectiveness of abundance and biomass curves in detecting environmental alterations in semi-arid region reservoirs

2018 ◽  
Vol 18 (2) ◽  
Author(s):  
Carlinda Raílly Medeiros ◽  
Evaldo de Lira Azevêdo ◽  
José Etham de Lucena Barbosa ◽  
Joseline Molozzi
Keyword(s):  
Arid Region ◽  
Water Resource Management ◽  
Environmental Indicators ◽  
Water Volume ◽  
Severe Drought ◽  
Drought Period ◽  
Littoral Region ◽  
Semi Arid Region ◽  
Effective Diagnosis ◽  
Semi Arid

Abstract For mitigation of environmental problems generated by bad water resource management, the first step is to develop methods for effective diagnosis. The potential bioindicator, mainly in the benthic community, in the evaluation of water quality is the structure of the community, associated with magnitude of environmental impact. The aim of the present study was to evaluate the effectiveness of abundance biomass curves (ABC) as tools to estimate ecological quality in reservoirs in the Brazilian semi-arid region. Two reservoirs, Epitácio Pessoa and Argemiro de Figueiredo were selected. These reservoirs are located in the watershed of the Paraíba River, in Northeast Brazil. Sampling was done at 40 sites in the littoral region of each reservoir, during the periods of higher and lower water volume in the reservoirs. ABC for semi-arid region reservoirs showed disparate results for biological and environmental indicators, because they had a better relationship with momentary variables (physical and chemical parameters). This may be related to the high occurrence of exotic species, principally Corbicula largillierti, which has a high biomass, in association with a severe drought period. ABC must thus be used with parsimony and combined with other indicators, for an accurate and coherent characterization.

scholarly journals APLICAÇÃO DE UM PROTOCOLO DE AVALIAÇÃO AMBIENTAL RÁPIDA EM DOIS RESERVATÓRIOS DO SEMIÁRIDO BRASILEIRO

2016 ◽  
Vol 20 (1) ◽  
Author(s):  
MAIARA TÁBATHA DA SILVA BRITO ◽  
SILVANO LIMA DO NASCIMENTO FILHO ◽  
GIRLENE FÁBIA SEGUNDO VIANA ◽  
MAURO MELO JÚNIOR
Keyword(s):  
Arid Region ◽  
Riparian Vegetation ◽  
Environmental Changes ◽  
Rapid Assessment ◽  
Water Volume ◽  
Monitoring Tool ◽  
Assessment Protocol ◽  
Semi Arid Region ◽  
Artificial Reservoirs ◽  
Semi Arid

In the semi-arid region of Brazil, artificial reservoirs are ecosystems of extremely important ecological and social. Due to pressures caused by long periods of pluviometric irregularity, the reservoirs Cachoeira I and Barra, located in the interior of Pernambuco, have been subject to very significant changes, marked mainly by the reduction of stored water volume, seasonal changes in the abiotic parameters, reduction of riparian vegetation and absence of macrophytes. All these changes were observed in this study through the use of an auxiliary monitoring tool, a rapid assessment protocol adapted for lentic ecosystems of semiarid, capable of detecting numerous types of environmental changes, assisting in monitoring these springs.

scholarly journals Spatio-temporal variation of cyanobacteria and cyanotoxins in public supply reservoirs of the semi-arid region of Brazil

2019 ◽  
Vol 79 (1) ◽  
Author(s):  
Ranielle Daiana dos Santos Silva ◽  
Juliana Santos Severiano ◽  
Dayany Aguiar de Oliveira ◽  
Camila Ferreira Mendes ◽  
Vanessa Virgínia Barbosa ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Secondary Metabolites ◽  
Arid Region ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii ◽  
Water Volume ◽  
Public Supply ◽  
Bioactive Secondary Metabolites ◽  
Semi Arid Region ◽  
Semi Arid

Cyanobacteria harmful algal blooms (CyanoHABs) have become increasingly frequent and intense in public supply reservoirs as a result of eutrophication and global climate change. The semi-arid region of Brazil has a well documented history of CyanoHABs but the underlying factors that control the excessive proliferation of these organisms and the production of their bioactive secondary metabolites are not comprehensively understood. This study aimed to identify the environmental factors that explain the spatial and temporal variations in the abundance of cyanobacteria and the concentration of cyanotoxins (microcystins, saxitoxins, and cylindrospermopsin) in semi-arid reservoirs. The following hypotheses were tested: (a) the largest biovolumes of potential toxin producing cyanobacteria occur when cyanotoxin concentrations are highest; and (b) the environmental factors that explain variations in biovolume of cyanobacteria also explain changes in cyanotoxins concentrations. Samples were taken from four reservoirs located in the Northeast region of Brazil, over a three-month period (October 2016 and February and June 2017). Of the 24 species of cyanobacteria identified, 13 were potentially toxin-producing. Physicochemical variables such as water volume of the reservoir, water transparency, soluble reactive phosphorus, and total phosphorus explained the abundance of cyanobacteria and the levels of cyanotoxins. These results corroborate the hypothesis that similar physicochemical conditions influence the abundance and diversity of cyanobacteria and cyanotoxins. Cyanobacterial blooms composed of more than one potential toxin producing species were observed in the studied reservoirs, where potential microcystin-producing species were the most common. Microcystins and saxitoxins were detected in all the reservoirs studied, while cylindrospermopsin and the cyanobacterium Cylindrospermopsis raciborskii were simultaneously recorded in only one reservoir (Camalaú Reservoir). Cylindrospermopsin was only detected in a reservoir for the first time in the State of Paraíba. Canonical redundancy analysis showed that the cyanotoxins were related to potential toxin producing species. These results corroborate the proposed hypothesis that there is a correlation between cyanotoxins and the biomass of potential producers. Also, there were situations where cyanotoxins were detected without the presence of potential producers. These results demonstrate the need for reassessment of potential toxin producing species of cyanobacteria in semi-arid reservoirs. This may lead to the identification and characterization of novel producers of these bioactive secondary metabolites.

scholarly journals Intensificação de sistemas de produção de palma forrageira por meio de consorciação rotativa com gramíneas, leguminosas e oleaginosas: uma revisão

2021 ◽  
Vol 14 (4) ◽  
pp. 2322-2343
Author(s):  
Kaique Renan da Silva Salvador ◽  
Alexandre Maniçoba da Rosa Ferraz Jardim ◽  
George do Nascimento Araújo Júnior ◽  
Cleber Pereira Alves ◽  
Antonio Gebson Pinheiro ◽  
...  
Keyword(s):  
Arid Region ◽  
Pigeon Pea ◽  
Climatic Conditions ◽  
Local Economy ◽  
Forage Production ◽  
Sustainable Systems ◽  
Forage Plants ◽  
Semi Arid Region ◽  
High Forage ◽  
Semi Arid

The low forage productivity in the Brazilian semi-arid is linked to water scarcity and climatic conditions, these abiotic disturbances affect the development of livestock and the local economy. Seeking to circumvent the situation, the use of forage species adapted to climatic conditions is of paramount importance, such as forage cactus, a crop rich in nutrients, much appreciated by animals, but lacking in fiber and protein, making it necessary to use other forage plants like sorghum, millet, pigeon pea and forage sunflower, both species have high levels of fiber and protein, and with this, they complement each other and enable the production of more balanced diets for herds. However, the higher yield of crops is observed with the implementation of resilient practices such as irrigation, adoption of mulch, intercropping, which promotes more sustainable systems with high forage potential. In this review, the objective was to evaluate the use of different agronomic practices to increase the productivity and sustainability of forage cactus crops and crops of regional appeal to the Brazilian semi-arid region. It is concluded that the sustainable intensification of agricultural crops, through complementary irrigation, mulch, intercropping with forage cactus, and plant species adapted to the Brazilian semi-arid region, can promote an increase in forage production without adverse effects on ecosystems.

scholarly journals The effects of work on the health of workers from textile hub in a semi-arid region of Brazil

2021 ◽  
Vol 8 (6) ◽  
pp. 2740
Author(s):  
Ramberta M. L. T. Queiroz ◽  
Beatriz Da C. A. Alves ◽  
Glaucia L. Da Veiga ◽  
Luis Vinícius De A. Sousa ◽  
Vagner Loduca ◽  
...  
Keyword(s):  
Leisure Time ◽  
Descriptive Study ◽  
Hospitalization Rate ◽  
Risk Prevention ◽  
Occupational Hazards ◽  
Health Records ◽  
Semi Arid Region ◽  
One Year ◽  
Main Activity ◽  
Semi Arid

Background: The main activity in the textile hub is to turn fibers into yarn, yarn into cloth and cloth into textile articles for household use. The aim of this study was to identify the occupational hazards in the textile industry.Methods: This is a transversal descriptive study that took place in the textile hub of Brazil. The environmental risk prevention program (PPRA) of the companies was used to analyse the workers' complaints through their occupational health records and to examine the collected data along with the effects on the worker's health after one year of work. A total of 128 workers took part in this study, with a mean age of 27.2 years. The statistical analysis was performed by using the software SPSS 20.0.Results: A year after, an increase in leisure time was observed thanks to the workers' monthly salaries, but an increase in hospitalization rate was noted, and hearing loss could also be detected.Conclusions: Therefore, the health of these workers was affected after one year of work.

Linking fish and crustacean taxonomic composition with seasonal contrasts in the soft-bottom intertidal zone

2020 ◽  
Author(s):  
M. A. Gondal ◽  
S. Iqbal ◽  
U. Atique ◽  
N. U. Saher ◽  
N. A. Qureshi ◽  
...  
Keyword(s):  
Species Richness ◽  
Water Temperature ◽  
Fish Species ◽  
Diversity Index ◽  
Taxonomic Composition ◽  
Primary Objective ◽  
Negative Effect ◽  
Fish Species Composition ◽  
One Year ◽  
Sw Monsoon

Abstract The primary objective of this study was to investigate the seasonal fish and crustacean variations concerning taxonomic composition, species richness, and diversity in sandy beach habitat. For this purpose, we investigated the Sonmiani Hor lagoon area during four distinct seasons, i.e., northeast (NE) monsoon, pre-monsoon, south-west (SW) monsoon, and post-monsoon for one year. During each haul, the net was pulled about 100m along the beach in 0.5m depth. The results showed a strong linear correlation between the diversity index and equitability in fishes (r = 0.978). The diversity index was strong negatively correlated with the abundance and biomass (r = -0.978, -0.972, respectively). The physical attributes like sea surface water temperature and salinity showed a strong negative effect on species assemblages (r = -0.981 and -0.943, respectively). The mean air and water temperature illustrated approximately 3°C difference during NE and pre-monsoon seasons. However, salinity, pH, and electrical conductivity did not show any significant seasonal variabilities. Under the ecological indices, the fish species displayed higher diversity (H’ = 3.19) during SW monsoon, whereas the lowest diversity was observed during pre-monsoon (H’ = 1.58). The equitability and species richness, however, remained more noticeable during SW monsoon (J’ = 0.81). The total number of individuals of fish and crustaceans reached 4799 with 3813 fish individuals and 986 individuals of crustaceans. A total of 27 families of fish while five crustacean families comprising of 30 genera and 38 fish species while ten genera and 17 species of crustaceans were recorded. Liza subviridis displayed the highest abundance among the sampled fish species. In conclusion, fish species constituted a significant part of the coastal fauna in the study area. The seasonal variations displayed distinct variations in fish species composition and diversity.

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