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

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.

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

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x1517 ◽

2018 ◽

Vol 30 (0) ◽

Cited By ~ 3

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.

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Application of Markov chains to Standardized Precipitation Index (SPI) in São Francisco River Basin

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2311 ◽

2019 ◽

Vol 14 (3) ◽

pp. 1

Author(s):

Esdras Adriano Barbosa dos Santos ◽

Tatijana Stosic ◽

Ikaro Daniel de Carvalho Barreto ◽

Laélia Campos ◽

Antonio Samuel Alves da Silva

Keyword(s):

Markov Chains ◽

River Basin ◽

Arid Region ◽

Standardized Precipitation Index ◽

Precipitation Index ◽

Severe Drought ◽

Sao Francisco River ◽

São Francisco River ◽

Semi Arid Region ◽

Semi Arid

This work evaluated dry and rainy conditions in the subregions of the São Francisco River Basin (BHSF) using the Standardized Precipitation Index (SPI) and Markov chains. Each subregion of the BHSF has specific physical and climatic characteristics. The data was obtained from the National Water Agency (ANA), collected by four pluviometric stations (representative of each subregion), covering 46 years of data, from 1970 to 2015. The SPI was calculated for the time scales of six and twelve months and transition probabilities were obtained using the Markov chain. Transition matrices showed that, at both scales, if the climate conditions were severe drought or rainy, switching to another class would be unlikely in the short term. Correlating this information with the probabilities of the stationary distribution, it was possible to find the regions that are most likely to be under rainy or dry weather in the future. The recurrence times calculated for the stations that belong to the semi-arid region were smaller when compared to the value of the return period of the representative station of Upper São Francisco that has higher levels of precipitation, confirming the predisposition of the semi-arid region to present greater chances of future periods of drought.

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

Iheringia Série Zoologia ◽

10.1590/s0073-47212011000300006 ◽

2011 ◽

Vol 101 (4) ◽

pp. 317-324 ◽

Cited By ~ 9

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.

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Toxorhynchites (Lynchiella) caatingensis sp. nov. (Diptera: Culicidae) from the semi-arid region of Brazil

Zootaxa ◽

10.11646/zootaxa.5072.2.2 ◽

2021 ◽

Vol 5072 (2) ◽

pp. 130-144

Author(s):

DAVID CAMPOS ANDRADE ◽

ROSELI LA CORTE

Keyword(s):

New Species ◽

Arid Region ◽

Species Complex ◽

Severe Drought ◽

Gene Fragment ◽

Exploratory Survey ◽

Semi Arid Region ◽

A New Species ◽

Semi Arid ◽

Tank Bromeliad

This publication describes a new species of mosquito of the genus Toxorhynchites Theobald, 1901, subgenus Lynchiella Lahille, 1904. The species was found during an exploratory survey of the Culicidae in the Caatinga biome, which is unique to Brazil and characterized by a semi-arid climate. Because of the specific characteristics of the biome, it has potential for endemism of species that have adapted to its restrictive conditions, particularly those imposed by severe drought. The new species, Toxorhynchites (Lynchiella) caatingensis, is a phytotelmic species that inhabits bromeliads and has an unknown biology. It belongs to a species complex that is hereafter referred to as the Violaceus Complex, which comprises three species that are found in the same type of habitat and have similar morphology: Tx. caatingensis n. sp., Tx. mariae (Bourroul, 1904) and Tx. violaceus (Wiedemann, 1820). We describe the larva, pupa, adult female and male genitalia of specimens collected as larvae from the tank bromeliad Aechmea aquilega (Salisb.) Griseb. The main distinctive characteristics of the species are the presence of three lateral tufts on the terminal abdominal segments (one pale and the others dark); a blue midline on the abdominal sterna; in the pupa, the pentagonal shape of the paddle and the length of seta 6-V. PCR reactions were carried out for the mitochondrial CO1 gene fragment, which placed the new species in the subgenus Lynchiella. No match was found with any species recorded in GenBank. The subgenus now includes 17 species.

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

Brazilian Journal of Aquatic Science and Technology ◽

10.14210/bjast.v20n1.6992 ◽

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.

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

Journal of Limnology ◽

10.4081/jlimnol.2019.1893 ◽

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.

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Sustainable Groundwater Exploitation Aiming at the Reduction of Water Vulnerability in the Brazilian Semi-Arid Region

Energies ◽

10.3390/en12050904 ◽

2019 ◽

Vol 12 (5) ◽

pp. 904 ◽

Cited By ~ 9

Author(s):

Roberto Cavalcante Júnior ◽

Marcos Vasconcelos Freitas ◽

Neilton da Silva ◽

Franklin de Azevedo Filho

Keyword(s):

Climate Change ◽

Arid Region ◽

Water Resource Management ◽

Power Plants ◽

Extreme Weather Events ◽

Renewable Energy Resources ◽

Groundwater Exploitation ◽

Water Vulnerability ◽

Semi Arid Region ◽

Semi Arid

Semi-arid regions have historically suffered from low water availability. In addition, the increasing frequency and intensity of extreme weather events credited to global climate change has made it increasingly clear that among the challenges faced by society water resource management is extremely necessary. In this context, desalination based on renewable energy resources integrated with production systems that make use of the waste resulting from this process becomes a socio-environmentally indicated alternative to expand existing supply strategies and sustainable water use in isolated locations, and/or areas distant from large urban centers, thus addressing local potential and reducing environmental impacts. This study assesses the use of Photovoltaic Solar Power Plants (PSPPs), as well as of residues generated in a Brackish Water Reverse Osmosis System (BWRO), in productive units linked to fish and family farming. This is as an alternative way to reduce water vulnerability in the Brazilian semi-arid area (BS), adhering to climate change adaptation measures in the light of Brazilian public policies through the Freshwater Program (Programa Água Doce—PAD), which aims to promote access to good quality water to approximately 500 thousand people in the Brazilian semi-arid region.

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Aerosol iron solubility in a semi-arid region: temporal trend and impact of anthropogenic sources

Tellus B ◽

10.3402/tellusb.v62i2.16519 ◽

2010 ◽

Vol 62 (2) ◽

Author(s):

Ashwini Kumar ◽

M. M. Sarin

Keyword(s):

Arid Region ◽

Temporal Trend ◽

Anthropogenic Sources ◽

Iron Solubility ◽

Semi Arid Region ◽

Semi Arid

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The Molecular Characterization and Biological Assessment of the Leaves Extracts of Loofah Reveal their Nutraceutical Potential

Recent Patents on Food Nutrition & Agriculturee ◽

10.2174/2212798411999201110211931 ◽

2020 ◽

Vol 11 ◽

Author(s):

Takoua Ben Hlel ◽

Feten Belhadj ◽

Fatih Gül ◽

Muhammed Altun ◽

Ayşe Şahin Yağlıoğlu ◽

...

Keyword(s):

Fatty Acids ◽

Phenolic Compounds ◽

Hela Cell ◽

Arid Region ◽

Biological Properties ◽

Biological Assessment ◽

Omega 3 ◽

Hela Cell Lines ◽

Semi Arid Region ◽

Semi Arid

Background:: Luffa cylindrica is a plant that is widely distributed in Africa and Asia and it can be grown in regions with tropical or subtropical climates. Few patents dealt with Loofah biological properties, including some functional foods formulated from its leaves. Objective:: This study aimed to structurally and functionally characterize the bioactive compounds of L. cylindrica leaves grown in two different environments. Methods:: The extracts of L. cylindrica leaves collected from two Tunisian locations: Essouasi (LE), a semi-arid region and Medenine (LM) an arid region, were investigated for their phenolic compounds and fatty acids using HPLC/TOF-MS and GCMS techniques respectively. Furthermore, the antioxidant capacity was evaluated with DPPH, Chelating effect, Hydroxyl radical and Superoxide anion scavenging activities while the anticancer activity against HeLa cell lines was assessed using xCELLigence real time cell analyzer and lactate dehydrogenase cytotoxicity assay. Results:: The antiproliferative capacity of both extracts was time and dose-dependent with LE presenting the lowest HeLa cell index (CI = 0.035 ± 0.018, 250 μg/ml). LE also showed the best cytotoxic capacity (56.49 ± 0.8%) and antioxidant potential (IC50 = 54.41 ± 1.12 μg/ml for DPPH and 12.12 ± 0.07 μg/ml for chelating effet). 14 phenolic compounds were detected in LE with ferulic acid being the major compound (5128.5 ± 4.09 μg Phenols/g) while LM had only 6 phenolics. GCMS analysis showed the presence of omega-3 fatty acids in LE. Conclusions:: Our findings suggest that L. cylindrica leaves, especially when collected from semi-arid regions, are promising for formulating nutraceuticals of interest.

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