scholarly journals Macroinvertebrates responses based on chemical and physical variables in urban streams

2021 ◽  
Vol 61 ◽  
pp. e20216183
Author(s):  
Germano Henrique Costa Barrilli ◽  
Natalia Felix Negreiros ◽  
Odete Rocha ◽  
José Roberto Verani
Keyword(s):  
Environmental Monitoring ◽  
Aquatic Ecosystems ◽  
Urban Streams ◽  
Monitoring Tool ◽  
Benthic Community Structure ◽  
Public Supply ◽  
Small Watersheds ◽  
Physical And Chemical Variables ◽  
Negative Impacts ◽  
Physical And Chemical

The Land uses and occupations around small watersheds generate negative impacts such as deterioration of water quality, environmental simplification, reduced availability of habitats for species, and loss of biodiversity. Benthic macroinvertebrates are an important aquatic community and are widely used in environmental monitoring actions in aquatic ecosystems, including urban streams, which are still little studied in Brazil. In our study, an urban headwater basin (Monjolinho River Basin) was studied on the benthic community structure, together with the physical and chemical variables of the water, as an environmental monitoring tool calculated by RHDEP, TSI, BMWP indexes and abundance-biomass curves. The results showed a gradient of environmental quality, where the best environments are a consequence of preserving the vegetation cover. These environments (Espraiado and Canchim) present groups sensitive to environmental degradation (Ephemeroptera, Plecoptera and Trichoptera), greater diversity and a better structure in the respective benthic macroinvertebrate assemblages. Among the streams sampled, one is very clean, four are moderately polluted, and one is severely polluted. Thus, considering that these streams’ waters are essential for public supply, actions to clean up and recover degraded environments are urgent and a priority.

scholarly journals Biomass and production of Cladocera in Furnas Reservoir, Minas Gerais, Brazil

2010 ◽  
Vol 70 (3 suppl) ◽  
pp. 879-887 ◽  
Author(s):  
RM Santos ◽  
NF. Negreiros ◽  
LC. Silva ◽  
O. Rocha ◽  
MJ. Santos-Wisniewski
Keyword(s):  
Secondary Production ◽  
Aquatic Ecosystems ◽  
Total Production ◽  
In Situ Data ◽  
Production Values ◽  
Physical And Chemical Variables ◽  
Order Of Magnitude ◽  
The Mean ◽  
Physical And Chemical

Secondary production of zooplankton, the main energy pathway in many aquatic ecosystems, is crucial to an Understanding of functioning of these systems function. In this study, we analyzed the magnitude and seasonal variations of the population density, biomass and secondary production of Cladocera in the Furnas Reservoir (Brazil). Samples were carried out monthly at 6 points in the reservoir, from August 2006 to July 2007. Main physical and chemical variables in the water column were measured in situ. Data on density, biomass and development times were obtained and used to calculate the secondary production of eight Cladocera species. The total production of Cladocera varied from 0.02 to 28.6 mgDWm-3.day-1, among the sampling sites. The highest values were recorded in spring and summer months (September to January), and were correlated to the increase in the biomass of the phytoplankton. The mean production:biomass ratio was 0.32. The level of production in Furnas Reservoir fell within the range of those reported in the literature and was of the same order of magnitude of the production values recorded for oligotrophic reservoirs. Cladocera production differed spatially inside the Sapucaí compartment and also in the temporal scale, seasonally.

Environmental monitoring of urban streams using a primary fish gill cell culture system (FIGCS)

2015 ◽  
Vol 120 ◽  
pp. 279-285 ◽  
Author(s):  
Sabine Schnell ◽  
Kafilat Bawa-Allah ◽  
Adebayo Otitoloju ◽  
Christer Hogstrand ◽  
Thomas H. Miller ◽  
...  
Keyword(s):  
Cell Culture ◽  
Environmental Monitoring ◽  
Culture System ◽  
Urban Streams ◽  
Cell Culture System ◽  
Fish Gill ◽  
Gill Cell

Back to the Future: Reducing Atmospheric Particulate Matter Levels to Improve Human Health

2021 ◽  
Author(s):  
Spyros Pandis
Keyword(s):  
Particulate Matter ◽  
Atmospheric Aerosols ◽  
Atmospheric Chemistry ◽  
Control Strategy ◽  
Atmospheric Particulate Matter ◽  
Anthropogenic Emissions ◽  
The Us ◽  
Negative Impacts ◽  
Predictive Understanding ◽  
Physical And Chemical

<p>The human development of our planet has a variety of negative impacts on the composition of its atmosphere at every scale – locally, regionally, and even globally. One of these dramatic changes has been the increase in the mass concentrations of sub-micrometer particles by one to sometimes two orders of magnitude over populated areas in the Northern Hemisphere. These atmospheric aerosols can cause serious health problems, reduce visibility, contribute to acidic deposition and material damage, but are also cooling the planet by reflecting sunlight back to space. Atmospheric chemistry occurs within a fabric of complicated atmospheric dynamics and physics. This interplay often results in nonlinear and often counterintuitive changes of the system when anthropogenic emissions change. A major goal of our research has been to gain a predictive understanding of the physical and chemical processes that govern the dynamics, size, and chemical composition of atmospheric aerosols.</p><p>To illustrate the advances in the experimental techniques and theoretical tools in atmospheric aerosol science, we will go back to the beginning of the 21<sup>st</sup> century and we will revisit the design a particulate matter control strategy for the Eastern US based on the data, knowledge, and tools available at that time. We will then look at the effects of the parts of this control strategy that have been materialized and their effects on public health using the current understanding. Finally, we will look forward in ways of further improving air quality in the US and Europe.</p>

scholarly journals Limnological study of Piraquara river (Upper Iguaçu basin): spatiotemporal variation of physical and chemical variables and watershed zoning

2003 ◽  
Vol 46 (3) ◽  
pp. 383-394 ◽  
Author(s):  
Paulo Henrique C. Marques ◽  
Haydée Torres de Oliveira ◽  
Eunice da Costa Machado
Keyword(s):  
River Basin ◽  
Oxygen Demand ◽  
Principal Component ◽  
Serra Do Mar ◽  
Spatial Gradients ◽  
Water Composition ◽  
Physical And Chemical Variables ◽  
Nitrite Nitrate ◽  
Physical And Chemical ◽  
Iguaçu River

The Piraquara river basin (Upper Iguaçu River basin - Brazil) was studied as an ecological system throughout a complete seasonal cycle, comprising the rainy and dry season. Analyzes of 16 physical and chemical water variables (dissolved oxygen, biochemical oxygen demand, temperature, pH, conductivity, total nitrogen, total phosphorus, ortophosphates, nitrite, nitrate, ammonium, reagent silicate, total suspended solids, chlorophyll - a, flow velocity and depth) showed correlations between water composition and watershed physiographic features, and the Principal Component Analysis allowed to evidence spatial gradients and seasonal differences. The sampling points were clustered in patches with homogeneous behavior, according to ecologycal concepts: patch 1, with strong influence of Serra do Mar mountains; patch 2, medium course, under Piraquara Dam influence and patch 3, under wetlands influence. Two main factors of serial discontinuity were identified: the Piraquara dam effect and the influence of wetlands. The watershed zoning based on limnological characteristics seeks to subsidize research and biomonitoring for this public springs area.

scholarly journals Water quality and potamoplankton evaluation of the Nile River in Upper Egypt

2015 ◽  
Vol 27 (2) ◽  
pp. 171-190 ◽  
Author(s):  
Ahmed Mohamed El-Otify ◽  
Isaac Agaiby Iskaros
Keyword(s):  
Community Structure ◽  
Zooplankton Community ◽  
Water Level Fluctuations ◽  
Main Stream ◽  
Upper Egypt ◽  
Physical And Chemical Variables ◽  
Different Seasons ◽  
High Current Velocity ◽  
Major Nutrients ◽  
Physical And Chemical

Aim: The composition, abundance, community structure of potamoplankton and major physical and chemical variables of the Nile water in Upper Egypt were investigated to assess its status in different seasons during 2007.MethodsWater samples were collected seasonally during 2007 from six investigated sites from variable depths at levels of 0, 2.5 and 5 m. The area of this investigation is defined as the southern 120 Km of the main stream of the Nile in Upper Egypt (24° 04’ – 25° 00’ latitudes and 32° 51’ – 32° 54’ longitudes), downstream of Aswan Old Dam.ResultsAltogether, 121 potamoplankton species, of which 85 related to phytoplankton and 36 appertaining to zooplankton were recorded. Most numerous phytoplankton were Chlorophyceae (42 species) followed by Bacillariophyceae (30 species). Cyanobacteria and Dinophyceae were less numerous with only 11 and 2 species, respectively. Zooplankton species were mainly belonging to three systematic groups namely; Rotifera (24 species), Copepoda (3 species) and Cladocera (9 species). Besides, other rare zooplankton including Platyhelminthes, Nemata and Ciliophora were sparsely encountered. The main hydrological conditions characterizing the investigated area include water level fluctuations (˂82 - ˃85 m above sea level), relatively high current velocity (0.8 - 1.3 m sec–1) and disposal of wastewater. Plankton populations were variably but rather weakly dependent on the major nutrients due to their excessive availability in accessible form for uptake by the producers. For phytoplankton, the community structure was categorized in relation to temperature, pH, SO42– and Mg2+. For zooplankton, the community structure was categorized in relation to conductivity as well as Mg2+. Sampling intervals were inadequate to demonstrate the existing successional pattern of the Nile potamoplankton community. Alterations in the phytoplankton community structure accompanied changes in water temperature represented by the alternate dominance between diatoms and cyanobacteria, while zooplankton community was always dominated by rotifers. Phytoplankton populations were numerically more abundant in autumn and zooplankton peaked in spring.ConclusionsWastewater disposal restricted the abundance of the Nile zooplankton assemblages mainly due to the numerical decline of Rotifera and Cladocera. Otherwise, wastewater did not exert major limits for phytoplankton. The data obtained in this investigation will be crucial to understand potamoplankton regulation and contribute to the knowledge regarding the Limnology of the Nile basin.

scholarly journals Phytoplankton abundance, dominance and coexistence in an eutrophic reservoir in the state of Pernambuco, Northeast Brazil

2011 ◽  
Vol 83 (4) ◽  
pp. 1313-1326 ◽  
Author(s):  
Giulliari A. S. T. Lira ◽  
Elcida L. Araújo ◽  
Maria Do Carmo Bittencourt-Oliveira ◽  
Ariadne N. Moura
Keyword(s):  
Rainy Season ◽  
Phytoplankton Community ◽  
Dry Season ◽  
Cylindrospermopsis Raciborskii ◽  
Phytoplankton Abundance ◽  
Vertical Variation ◽  
Total Phytoplankton ◽  
Physical And Chemical Variables ◽  
Different Depths ◽  
Physical And Chemical

The present study reports the phytoplankton abundance, dominance and co-existence relationships in the eutrophic Carpina reservoir, Pernambuco, Brazil. Sampling was carried out at six different depths bimonthly at a single reservoir spanning two climatic periods: dry season (January, September, and November 2006) and rainy season (March, May, and July 2006). Density, abundance, dominance, specific diversity and equitability of the community were determined, along with chlorophyll a, and physical and chemical variables of the environment. Eight species were considered abundant, and their densities corresponded to more than 90% of the total phytoplankton community quantified. Cyanobacteria represented more than 80% of this density. Cylindrospermopsis raciborskii was the only dominant taxon in the dry season, and was co-dominant in the rainy season. C. raciborskii, Planktothrix agardhii and Geitlerinema amphibium had the greatest densities and lowest vertical variation coefficients. The statistical analysis indicated relationships with vertical and seasonal variations in the phytoplankton community and the following variables: total dissolved solids, water temperature, electrical conductivity and pH. The changes in the environmental variables were discrete and regulated by the establishment of precipitation however, they were able to promote vertical and seasonal instability in the structure of the phytoplankton community.

scholarly journals Environmental quality evaluation of lakes in the Rio Grande do Sul coastal plain

2007 ◽  
Vol 50 (4) ◽  
pp. 673-685 ◽  
Author(s):  
Catarina da Silva Pedrozo ◽  
Odete Rocha
Keyword(s):  
Environmental Quality ◽  
Sewage Treatment ◽  
Principal Component ◽  
Organic Pollution ◽  
Physical And Chemical Variables ◽  
Environmental Element ◽  
Different Characteristics ◽  
Physical And Chemical ◽  
The Town

The purpose of the present work was to evaluate the environmental quality of Marcelino, Pinguela, Peixoto, Palmital, Malvas and Do Passo lakes, interconnected by canals and located in the district of Osório, RS. In this context, 29 physical and chemical variables were analyzed with sampling carried out in January, May, July and October 1997 to verify the environmental quality of the system and the existence of a gradient of quality. Canonical Analysis was applied to the data of all environmental variables measured, and showed that the lakes had different characteristics as a consequence of the organic pollution received. Marcelino lake received continuous input of organic matter from the sewage treatment works in the town of Osório, whereas Peixoto, Pinguela, Palmital, Malvas and Do Passo lakes resembled other water bodies described in the region, not showing, so far, signs of degradation caused by the input of effluents. Principal Component Analysis selected environmental element were directly linked to organic pollution, that reflected sequential non-recent effects of contamination.

scholarly journals Predictive Models to Estimate Carbon Stocks in Agroforestry Systems

Forests ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1240
Author(s):  
Maria Fernanda Magioni Marçal ◽  
Zigomar Menezes de Souza ◽  
Rose Luiza Moraes Tavares ◽  
Camila Viana Vieira Farhate ◽  
Stanley Robson Medeiros Oliveira ◽  
...  
Keyword(s):  
Land Use ◽  
Random Forest ◽  
Carbon Stock ◽  
Agroforestry System ◽  
Agroforestry Systems ◽  
Forest Fragment ◽  
Random Forest Algorithm ◽  
Land Use Systems ◽  
Physical And Chemical Variables ◽  
Physical And Chemical

This study aims to assess the carbon stock in a pasture area and fragment of forest in natural regeneration, given the importance of agroforestry systems in mitigating gas emissions which contribute to the greenhouse effect, as well as promoting the maintenance of agricultural productivity. Our other goal was to predict the carbon stock, according to different land use systems, from physical and chemical soil variables using the Random Forest algorithm. We carried out our study at an Entisols Quartzipsamments area with a completely randomized experimental design: four treatments and six replites. The treatments consisted of the following: (i) an agroforestry system developed for livestock, (ii) an agroforestry system developed for fruit culture, (iii) a conventional pasture, and (iv) a forest fragment. Deformed and undeformed soil samples were collected in order to analyze their physical and chemical properties across two consecutive agricultural years. The response variable, carbon stock, was subjected to a boxplot analysis and all the databases were used for a predictive modeling which in turn used the Random Forest algorithm. Results led to the conclusion that the agroforestry systems developed both for fruit culture and livestock, are more efficient at stocking carbon in the soil than the pasture area and forest fragment undergoing natural regeneration. Nitrogen stock and land use systems are the most important variables to estimate carbon stock from the physical and chemical variables of soil using the Random Forest algorithm. The predictive models generated from the physical and chemical variables of soil, as well as the Random Forest algorithm, presented a high potential for predicting soil carbon stock and are sensitive to different land use systems.

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