Spatial and temporal variation in species composition of ciliates communities (Alveolata, Ciliophora) from tropical urban and rural streams

2021 ◽  
Vol 57 ◽  
pp. 24
Author(s):  
Luiz Felipe Machado Velho ◽  
Suzana de Fátima Rodrigues de Castro ◽  
Fernando Miranda Lansac-Tôha ◽  
Bianca Ramos Meira ◽  
Felipe Rafael de Oliveira ◽  
...  
Keyword(s):  
Species Composition ◽  
Light Availability ◽  
Domestic Wastewater ◽  
Taxonomic Composition ◽  
Urban Streams ◽  
Organic Load ◽  
Spatial And Temporal Variation ◽  
Agricultural Activities ◽  
Spatial And Temporal Patterns ◽  
Rural And Urban

The aim of this study was to investigate the spatial and temporal patterns in species composition of ciliates, in rural streams, affected by agricultural activities, and urban streams, impacted by domestic wastewater. Samplings were taken in two different periods of the year, in the headwater, middle and mouth stretch of ten streams. We recorded 143 species of ciliates, distributed in 14 groups, standing out Hymenostomatia, Peritrichia and Hypotrichia. Our results showed significant spatial (between rural and urban streams) and, especially, temporal differences (between winter and summer periods) in the ciliates taxonomic composition. Such differences seem to be not related to the organic load that was quite similar among streams and periods sampled. Rather, the changes in ciliates composition are probably driving mainly by other enviromental variables such as resources, determined by the spatial diferences in light availability, and flow water velocity and discharge, which present high temporal dissimilarity.

Sobre a Formação da Mão de Obra Industrial no Brasil e a Imigração Estrangeira - 1890-1930

GEOgraphia ◽  
2009 ◽  
Vol 3 (5) ◽  
pp. 47
Author(s):  
Satiê Mizubuti
Keyword(s):  
Urban Areas ◽  
Rio De Janeiro ◽  
Sao Paulo ◽  
São Paulo ◽  
Agricultural Activities ◽  
Work Relations ◽  
Trade Unionism ◽  
Rural And Urban ◽  
First Republic ◽  
International Demand

Resumo A formação da mão-de-obra no Brasil no decorrer da Primeira República (1890-1930) se fez de forma acelerada e em dois campos simultaneamente no rural e no urbano. No rural, pelo aquecimento da demanda internacional pelo café brasileiro, e, no urbano, pelo início da industrialização, principalmente, nas cidades do Rio de Janeiro e de São Paulo. Tanto nas atividades agrícolas, como nas industriais, a presença e a participação do imigrante estrangeiro foram hegemônicas e decisivas. É preciso considerar que a abolição da escravatura havia ocorrido em 1888, criando um esvaziamento do mercado de trabalho no Brasil. Palavras chave: imigração estrangeira; cafeicultura, industrialização; sindicalismo; relações de trabalho.Resumo Labor formation in Brazil took an accelerated rhythmus during the First Republic (1890-1930) in two fields simultaneously: rural and urban. In the rural sector it was due to an increase in international demand for Brazilian coffee. In the urban areas, meanwhile, the beginning of industrialization, specially in Rio de Janeiro and São Paulo, was the main cause. Not only in the agricultural activities. but also in the industries, the presence and participation of foreign immigrants were decisive. The abolition os slavery in 1888 must be considered as part of this context, as it changed the labour market. Keywords: foreign immigration; coffee growing; industrialization; trade unionism; work relations.

scholarly journals Diversity of Algae and Cyanobacteria and Bioindication Characteristics of the Alpine Lake Nesamovyte (Eastern Carpathians, Ukraine) from 100 Years Ago to the Present

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 256
Author(s):  
Petro M. Tsarenko ◽  
Olena P. Bilous ◽  
Olha M. Kryvosheia-Zakharova ◽  
Halyna H. Lilitska ◽  
Sophia Barinova
Keyword(s):  
Species Composition ◽  
Structural Changes ◽  
Algal Species ◽  
Taxonomic Composition ◽  
Alpine Lake ◽  
Algal Flora ◽  
Ecological Analysis ◽  
Modern Species ◽  
Eastern Carpathians ◽  
Infraspecific Taxa

The species diversity and changes in the structural dynamics of the algal flora from the alpine lake Nesamovyte has been studied for 100 years. During the period of investigations, 234 species (245 infraspecific taxa) were revealed to cover more than 70% of the modern species composition of the studied lake. The modern biodiversity of algae is characterized by an increase in the number of widespread forms, a change from the baseline “montane” complex in comparison to the beginning of the 20th century. Nevertheless, the Nesamovyte Lake still has a unique algae composition that is typical for high-mountainous European lakes. The presence of a different complex of conventionally arctic species of algae, in particular, diatoms is discussed. Structural changes in the taxonomic composition of the algal flora of the lake as well as in the complex of the leading genera, species and their diversity are revealed. An ecological analysis of the algal species composition of the lake showed vulnerability and degradation to the ecosystem of the lake. On this basis, the issue regarding the question of protection and preservation of the algae significance and uniqueness of the flora of algae in the Nesamovyte Lake are discussed.

scholarly journals The Diversification and Intensification of Crop Rotations under No-Till Promote Earthworm Abundance and Biomass

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 919
Author(s):  
María Pía Rodríguez ◽  
Anahí Domínguez ◽  
Melisa Moreira Ferroni ◽  
Luis Gabriel Wall ◽  
José Camilo Bedano
Keyword(s):  
Species Composition ◽  
Crop Production ◽  
Positive Impact ◽  
Organic Matter Content ◽  
Taxonomic Composition ◽  
Matter Content ◽  
Crop Rotations ◽  
Subtle Change ◽  
No Till ◽  
Novel Approach

The diversification and intensification of crop rotations (DICR) in no-till systems is a novel approach that aims to increase crop production, together with decreasing environmental impact. Our objective was to analyze the effect of different levels of DICR on the abundance, biomass, and species composition of earthworm communities in Argentinean Pampas. We studied three levels of DICR—typical rotation (TY), high intensification with grass (HG), and with legume (HL); along with three references—natural grassland (NG), pasture (PA), and an agricultural external reference (ER). The NG had the highest earthworm abundance. Among the DICR treatments, abundance and biomass were higher in HL than in HG and, in both, these were higher than in TY. The NG and PA had a distinctive taxonomic composition and higher species richness. Instead, the DICR treatments had a similar richness and species composition. Earthworm abundance and biomass were positively related to rotation intensity and legume proportion indices, carbon input, and particulate organic matter content. The application of DICR for four years, mainly with legumes, favors the development of earthworm populations. This means that a subtle change in management, as DICR, can have a positive impact on earthworms, and thus on earthworm-mediated ecosystem services, which are important for crop production.

Nitrification and denitrification using a single biofilter packed with granular sulfur

2003 ◽  
Vol 47 (11) ◽  
pp. 153-156 ◽  
Author(s):  
J.-S. Kim ◽  
Y.-W. Hwang ◽  
C.-G. Kim ◽  
J.-H. Bae
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Domestic Wastewater ◽  
Organic Load ◽  
Low Carbon ◽  
Municipal Wastewater Treatment ◽  
Treatment Facility ◽  
Experimental Conditions ◽  
Nitrification And Denitrification ◽  
Denitrification Process

This study was performed to develop a granular sulfur packed nitrification/denitrification process employing a uniquely designed single biofilter, which treated a relatively low carbon loaded domestic wastewater taken from a primary clarifier at a municipal wastewater treatment facility. The system was tested on varying experimental conditions, e.g. inflow flow, organic load and nitrogen load. Regardless of flow rate being increased, SS and COD was unvaryingly removed up to 90 and 80%, respectively. Moreover, TKN was also decomposed up to 90%. Increase in COD load gradually led to escalating level of non-biodegradable compounds observed in effluent. Nitrification was accomplished as high as 92%, whereas denitrification was achieved up to approximately 87%. For a while, nitrification and denitrification were observed at 0.65 and 0.55 kg/m3áday, respectively. Eventually, T-N was decomposed as high as 46%. It was concluded that granular sulfur can be used for not only electron donor, but also for a media to properly treat low carbon loaded wastewater and to filter SS efficiently.

Mass transfer approach and the designing of horizontal subsurface flow constructed wetland systems treating waste stabilisation pond effluent

2018 ◽  
Vol 78 (12) ◽  
pp. 2639-2646 ◽  
Author(s):  
Anita M. Rugaika ◽  
Damian Kajunguri ◽  
Rob Van Deun ◽  
Bart Van der Bruggen ◽  
Karoli N. Njau
Keyword(s):  
Mass Transfer ◽  
Constructed Wetlands ◽  
Rate Constants ◽  
Removal Rate ◽  
Subsurface Flow ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Organic Load ◽  
Mass Transfer Effect ◽  
Horizontal Subsurface Flow

Abstract Pilot-scale constructed wetlands (CWs) that allowed wastewater to flow with high interstitial velocities in a controlled environment were used to evaluate the possibility of using mass transfer approach to design horizontal subsurface flow constructed wetlands (HSSF-CWs) treating waste stabilisation ponds (WSPs) effluent. Since CW design considers temperature which is irrelevant in tropics, mass transfer approach could improve the design. HSSF-CWs were operated in batch recycle mode as continuous stirred tank reactors (CSTR) at different interstitial velocities. The overall removal rate constants of chemical oxygen demand (COD) at various interstitial velocities were evaluated in mesocosms that received pretreated domestic wastewater. The mean overall removal rate constants were 0.43, 0.69, 0.74 and 0.73 d−1 corresponding to interstitial velocities of 15.43, 36, 56.57 and 72 md−1, respectively. Results showed that the interstitial velocities up to 36 md−1 represented a range where mass transfer effect was significant and, above it, insignificant to the COD removal process. Since WSPs effluent has high flow rates and low organic load, it is possible to induce high interstitial velocities in a HSSF-CW treating this effluent, without clogging and overflow. The performance of these HSSF for tertiary treatment in tropical areas could be improved by considering flow velocity when designing.

scholarly journals Monitoring Post-Fire Recovery of Chaparral and Conifer Species Using Field Surveys and Landsat Time Series

2019 ◽  
Vol 11 (24) ◽  
pp. 2963
Author(s):  
Christopher L. Kibler ◽  
Anne-Marie L. Parkinson ◽  
Seth H. Peterson ◽  
Dar A. Roberts ◽  
Carla M. D’Antonio ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Time Series ◽  
Land Cover ◽  
Species Composition ◽  
Vegetation Cover ◽  
Spatial And Temporal Variation ◽  
Conifer Species ◽  
Burn Scar ◽  
Green Vegetation ◽  
Normalized Burn Ratio

Recovery trajectories derived from remote sensing data are widely used to monitor ecosystem recovery after disturbance events, but these trajectories are often retrieved without a precise understanding of the land cover within a scene. As a result, the sources of variability in post-disturbance recovery trajectories are poorly understood. In this study, we monitored the recovery of chaparral and conifer species following the 2007 Zaca Fire, which burned 97,270 ha in Santa Barbara County, California. We combined field survey data with two time series remote sensing products: the relative delta normalized burn ratio (RdNBR) and green vegetation (GV) fractions derived from spectral mixture analysis. Recovery trajectories were retrieved for stands dominated by six different chaparral species. We also retrieved recovery trajectories for stands of mixed conifer forest. We found that the two remote sensing products were equally effective at mapping vegetation cover across the burn scar. The GV fractions (r(78) = 0.552, p < 0.001) and normalized burn ratio (r(78) = 0.555, p < 0.001) had nearly identical correlations with ground reference data of green vegetation cover. Recovery of the chaparral species was substantially affected by the 2011–2017 California drought. GV fractions for the chaparral species generally declined between 2011 and 2016. Physiological responses to fire and drought were important sources of variability between the species. The conifer stands did not exhibit a drought signal that was directly correlated with annual precipitation, but the drought likely delayed the return to pre-fire conditions. As of 2018, 545 of the 756 conifer stands had not recovered to their pre-fire GV fractions. Spatial and temporal variation in species composition were important sources of spectral variability in the chaparral and conifer stands. The chaparral stands in particular had highly heterogeneous species composition. Dominant species accounted for between 30% and 53% of the land cover in the surveyed chaparral patches, so non-dominant land cover types strongly influenced remote sensing signals. Our study reveals that prolonged drought can delay or alter the post-fire recovery of Mediterranean ecosystems. It is also the first study to critically examine how fine-scale variability in land cover affects time series remote sensing analyses.

Phytoplankton photoadaptation during the spring period in Lake Zürich

1995 ◽  
Vol 32 (4) ◽  
pp. 59-62 ◽  
Author(s):  
Ferdinand Schanz ◽  
Judith Burri
Keyword(s):  
Species Composition ◽  
Light Availability ◽  
Plankton Community ◽  
Short Term ◽  
Spring Period ◽  
Constant Structure ◽  
Phytoplankton Communities ◽  
Lake Zürich

Long- and short-term photoadaptations as a response to increased light availability in spring phytoplankton communities in Lake Zürich have been investigated. At various stages fundamental changes in species composition and species adaptation in a plankton community of approximately constant structure were apparent.

scholarly journals Spatial and temporal variation of phytoplankton in a tropical eutrophic river

2016 ◽  
Vol 76 (3) ◽  
pp. 600-610 ◽  
Author(s):  
L. M. Santana ◽  
M. E. B. Moraes ◽  
D. M. L. Silva ◽  
C. Ferragut
Keyword(s):  
River Flow ◽  
Light Availability ◽  
Abundant Species ◽  
Northeastern Brazil ◽  
Spatial And Temporal Variation ◽  
Rainy Period ◽  
Lotic Ecosystem ◽  
Phytoplankton Structure ◽  
Accumulated Rainfall ◽  
Eutrophic River

Abstract This study aims to evaluate the environmental factors determining of the changes in phytoplankton structure in spatial (upper, middle and lower course) and seasonal (dry and rainy period) scales in a eutrophic river (Almada River, northeastern Brazil). In the study period, total accumulated rainfall was below of the historic average, resulting in flow reduction, mainly in rainy period. High orthophosphate concentration was found at the sampling sites. Phytoplankton chlorophyll a increased from upstream to downstream. Geitlerinema splendidum (S1) and Chlamydomonas sp. (X2) were the most abundant species in the upper course and several species of diatoms (D), Euglenophyceae (W1, W2) and Chlorophyceae (X1) in the middle and lower course. The functional groups were found to be characteristic of lotic ecosystem, shallow, with low light availability, rich in organic matter and eutrophic environments. We conclude that phytoplankton community structure was sensitive to change of the river flow and nutrient availability in spatial and seasonal scale in a tropical river.

scholarly journals Environmental and ecological factors mediate taxonomic composition and body size of polyplacophoran assemblages along the Peruvian Province

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Christian M. Ibáñez ◽  
Melany Waldisperg ◽  
Felipe I. Torres ◽  
Sergio A. Carrasco ◽  
Javier Sellanes ◽  
...  
Keyword(s):  
Body Size ◽  
Species Composition ◽  
Size Structure ◽  
Environmental Gradients ◽  
Ecological Factors ◽  
Taxonomic Composition ◽  
Latitudinal Gradients ◽  
Size Segregation ◽  
Biogeographic Patterns ◽  
Diversity Gradient

Abstract Intertidal communities’ composition and diversity usually exhibit strong changes in relation to environmental gradients at different biogeographical scales. This study represents the first comprehensive diversity and composition description of polyplacophoran assemblages along the Peruvian Province (SE Pacific, 12°S–39°S), as a model system for ecological latitudinal gradients. A total of 4,775 chitons from 21 species were collected on twelve localities along the Peruvian Province. This sampling allowed us to quantitatively estimate the relative abundance of the species in this assemblage, and to test whether chitons conform to elementary predictions of major biogeographic patterns such as a latitudinal diversity gradient. We found that the species composition supported the division of the province into three ecoregional faunal groups (i.e. Humboldtian, Central Chile, and Araucanian). Though chiton diversity did not follow a clear latitudinal gradient, changes in species composition were dominated by smaller scale variability in salinity and temperature. Body size significantly differed by ecoregions and species, indicating latitudinal size-structure assamblages. In some localities body size ratios differed from a random assemblage, evidencing competition at local scale. Changes in composition between ecoregions influence body size structure, and their overlapping produce vertical size segregation, suggesting that competition coupled with environmental conditions structure these assemblages.

Spatial and temporal variation in the abundance and taxonomic composition of estuarine and terrestrial macrofauna associated with mangrove logs

2013 ◽  
Vol 94 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Jennifer T.M. Andrade ◽  
Natália Barros Palhano ◽  
Claudia Helena Tagliaro ◽  
Colin Robert Beasley
Keyword(s):  
Dominant Species ◽  
Multivariate Analyses ◽  
Taxonomic Composition ◽  
Economic Importance ◽  
Spatial And Temporal Variation ◽  
Mangrove Forests ◽  
Tidal Channel ◽  
Total Abundance ◽  
Significant Difference ◽  
Northern Brazil

Brazilian mangroves have ecological and economic importance, with molluscs, crustaceans and polychaetes being diverse and common faunal groups. The present study characterizes the macrofauna associated with logs from two mangrove forests in Pará State, northern Brazil, sampled in September, January and April, between 2008 and 2010, at three different distances from a tidal channel (2, 10, 20 m). In each forest, five logs (diameter/length: 10/40 cm) were randomly selected at each distance, totalling 15 logs per sampling date. The macrofauna was removed, counted and identified. Three-way analysis of variance was used to compare mean numbers of individuals, numbers of taxa and Berger–Parker dominance per log, between forests and among sampling dates and distances from the tidal channel. Non-metric multidimensional scaling and permutational multivariate analyses of variance were used to investigate macrofaunal structure in relation to the three factors. A total of 5437 individuals from both estuarine and terrestrial faunas was found in both forests, with 85 taxa distributed among Mollusca, Annelida, Arthropoda and Nemertea. Abundance increased from September through January to April in both mangrove forests. The most dominant species was Neoteredo reynei, representing 48% of total abundance. No significant difference in any variable was found among the two forests and between the three distances. Logs may represent a stable microhabitat for the macrofauna, with little variation in humidity, salinity or temperature, despite different distances from the tidal channel. However, macrofaunal structure varied significantly between forests and among sampling dates, probably due to seasonal differences in precipitation and salinity between both locations.

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