Activity, substrate selection, and effect of a simulated Amazon flood regime on the behaviour of the apple snail, Pomacea bridgesii

2015 ◽  
Vol 66 (9) ◽  
pp. 815 ◽  
Author(s):  
Timoteo Tadashi Watanabe ◽  
Gustavo Yomar Hattori ◽  
Bruno Sampaio Sant'Anna
Keyword(s):  
Daily Activity ◽  
Significant Proportion ◽  
Flood Pulse ◽  
Substrate Selection ◽  
Apple Snail ◽  
Pulse Regime ◽  
Amazon Floodplain ◽  
Flood Regime ◽  
Maximum Water Level ◽  
Water Tanks

This study investigated the behaviour of Pomacea bridgesii, describing the daily activity, substrate selection and the influence of the flood regime in the Amazon, the species’ native habitat. The present study described the daily activity and substrate selection, and evaluated the activity adaptations of the gastropods in a simulated flood-pulse regime. Gastropods were collected in Amazonas, Brazil, in June 2013. Assessments of the daily behaviour, substrate selection, and flood-pulse simulation were made in experimental water tanks. The snails were observed hourly for 48h, and their behaviour recorded on an ethogram. The snails were more active during the night, when up to 80% of them moved about. In general, during both day and night, the gastropods used the pebble substrate most often. Comparing the day periods, a significant proportion of the individuals that were using the pebbles moved to other substrates (t=5; d.f.=2; P=0.03). The interaction of the behaviour of P. bridgesii with the simulated flood-pulse regime showed a statistical difference between the dry period and the period of maximum water level. The water regime of the Amazon floodplain directly influenced the activity of P. bridgesii, with responses including self-burying and activity interruption, with the operculum closed to minimise water loss.

Multidecadal variability of the Tonle Sap Lake flood pulse regime

2021 ◽  
Author(s):  
Aifang Chen ◽  
Junguo Liu ◽  
Matti Kummu ◽  
Olli Varis ◽  
Qiuhong Tang ◽  
...  
Keyword(s):  
Flood Pulse ◽  
Pulse Regime ◽  
Multidecadal Variability ◽  
Tonle Sap Lake ◽  
Tonle Sap

scholarly journals Water quality changes in floodplain lakes due to the Amazon River flood pulse: Lago Grande de Curuaí (Pará)

2011 ◽  
Vol 71 (3) ◽  
pp. 601-610 ◽  
Author(s):  
AG Affonso ◽  
C. Barbosa ◽  
EMLM. Novo
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Chlorophyll A ◽  
Water Use ◽  
Flood Pulse ◽  
Human Consumption ◽  
Trophic State Index ◽  
Amazon Floodplain ◽  
Marginal Areas ◽  
State Index

Assurance of water quality for human consumption is essential for public health policies. In the Amazon floodplain, the seasonal water level variation causes periodic flooding of marginal areas that are usually used for settlements, agriculture and livestock. Therefore, the exchange of materials between the terrestrial and aquatic ecosystem affects the proportion of suspended and dissolved components in water and its physical-chemical characteristics, and consequently the quality of the water used by local people. Following this approach, the aim of this study is to evaluate changes in water quality in Lago Grande de Curuaí floodplain, Óbidos, Pará in response to the flood pulse, during one hydrological year from 2003 to 2004, based on water use classes (according to National Water Agency 357/2005 resolution) using chlorophyll-a and dissolved oxygen concentration as parameters and the eutrophication index. Ordinary kriging was applied to interpolate chlorophyll-a and dissolved oxygen and to predict values at non sampled locations. Each location was then classified according to water use acceptable parameters and to Carlson Trophic State Index modified by Toledo to map lake water classes and trophic status. The result showed that Lago Grande de Curuaí floodplain is a supereutrophic system, with levels of dissolved oxygen and chlorophyll-a not suitable for human supply during the receding water phase. These areas are located near the riverine communities, which can cause health problems due to the presence of potentially toxic algae. Therefore, monitoring water quality in Amazon lakes is essential to ensure the availability has appropriate quality for human and animal supplies.

scholarly journals Abiotic variability among different aquatic systems of the central Amazon floodplain during drought and flood events

2015 ◽  
Vol 75 (4 suppl 1) ◽  
pp. 60-69 ◽  
Author(s):  
A. G. Affonso ◽  
H. L. Queiroz ◽  
E. M. L. M. Novo
Keyword(s):  
High Water ◽  
Flood Pulse ◽  
Aquatic Systems ◽  
Water Phase ◽  
Multivariate Statistical ◽  
Temperature Conductivity ◽  
Central Amazon ◽  
Amazon Floodplain ◽  
Main River ◽  
Hydrological Phases

Abstract This paper examines water properties from lakes, (depression lakes, sensu Junk et al., 2012), channels (scroll lakes with high connectivity, sensu Junk et al., 2012) and paleo-channels (scroll lakes with low connectivity-sensu Junk et al., 2012, locally called ressacas) located in Mamirauá Sustainable Development Reserve, in Central Amazon floodplain, Amazonas, Brazil. We analysed surface temperature, conductivity, pH, dissolved oxygen, turbidity, transparency, suspended inorganic and organic matter, chlorophyll-a, pheophytin, total nitrogen, total phosphorus, organic and inorganic carbon in 2009 high water phase, 2009 and 2010 low water phases. Multivariate statistical analyses of 24 aquatic systems (6 ressacas, 12 lakes and 6 channels, 142 samples) were applied to the variables in order to: 1) quantify differences among aquatic system types; 2) assess how those differences are affected in the different phases of the hydrological year. First, we analysed the entire set of variables to test for differences among phases of the hydrological year and types of aquatic systems using a PERMANOVA two-way crossed design. The results showed that the all measured limnological variables are distinct regarding both factors: types of aquatic systems and hydrological phases. In general, the magnitude and amplitude of all variables were higher in the low water phase than in the high water phase, except for water transparency in all aquatic system’s types. PERMANOVA showed that the differences between aquatic system’s types and hydrological phases of all variables were highly significant for both main factors (type and phase) and for the type x phase interaction. Limnological patterns of Amazon floodplain aquatic systems are highly dynamic, dependent on the surrounding environment, flood pulse, main river input and system type. These patterns show how undisturbed systems respond to natural variability in such a diverse environment, and how distinct are those aquatic systems, especially during the low water phase. Aquatic systems in Mamirauá floodplain represent limnological patterns of almost undisturbed areas and can be used as future reference for comparison with disturbed areas, such as those of the Lower Amazon, and as a baseline for studies on the effects of anthropogenic influences and climate change and on Amazon aquatic ecosystem.

Response of fish assemblage structure to changing flood and flow pulses in a large subtropical river

2017 ◽  
Vol 68 (2) ◽  
pp. 319 ◽  
Author(s):  
L. A. Espínola ◽  
A. P Rabuffetti ◽  
E Abrial ◽  
M. L. Amsler ◽  
M. C. A. Blettler ◽  
...  
Keyword(s):  
Fish Assemblage ◽  
Fish Assemblages ◽  
Flood Pulse ◽  
Fish Assemblage Structure ◽  
Migratory Species ◽  
Maximum Water Level ◽  
Flood Pulses ◽  
Maximum Water ◽  
Lotic Habitat ◽  
Spatio Temporal

Fish assemblages recorded from August 2010 to July 2013 in two lotic and lentic environments of the Middle Paraná River floodplain were studied in the light of flood and flow pulse variations. Three flood pulses occurred during the period of study, each with a different magnitude, duration and timing. Instead four flow pulses were recorded during this period. The varied hydrological conditions had an influence on the ichthyofauna. The fish species richness in both lentic and lotic habitat was negatively correlated with the maximum water level and fish assemblages were spatially and temporally structured according to their different reproductive strategies. Long- and short-distance migratory species were dominant after the flood pulse of the highest intensity and longest duration, whereas sedentary fish and internal fertilisation prevailed during flow pulses and lower flood pulses. Fish assemblage similarity was generally low between habitats during flood and flow pulses, but increased after those events depending on their magnitude, duration and timing. Apparently, flow pulses would also function like floods, as mechanisms of spatio-temporal structuring of fish assemblages.

scholarly journals Nutrients and water-forest interactions in an Amazon floodplain lake: an ecological approach

2013 ◽  
Vol 25 (2) ◽  
pp. 169-182 ◽  
Author(s):  
Fabio Aprile ◽  
Assad José Darwich
Keyword(s):  
Hydrological Cycle ◽  
Nutrient Content ◽  
Flood Pulse ◽  
Negro River ◽  
Amazon Floodplain ◽  
Flux Model ◽  
Physical And Chemical ◽  
Paspalum Repens ◽  
The City

AIM: Catalão Lake was surveyed between 2002 and 2011 with the aim of studying seasonality of the flow of nutrients between water, sediment and aquatic macrophytes. The role of the flood pulse and the ecological mechanisms influencing the forest-water interactions in the Amazon floodplain were discussed; METHODS: Catalão Lake is located in the Amazon floodplain (03º 08'-03º 14' S and 59º 53'-59º 58' W), near the confluence of the Solimões and Negro rivers, approximately 3000 m from the port of CEASA, near the city of Manaus. It is considered to be a mixed water lake because it receives white waters rich in sediments from the Solimões River and black waters with humic substances from the Negro River. Physical and chemical parameters including C, N and P levels were studied in the diverse compartments, and a flux model was developed; RESULTS: There is a strong nutritional (C, N and P) and ionic (Na+, K+, Ca2+, Mg2+, Cl-, HCO3-, CO3(2-) and SO4(2-)) flow from the rivers to the lake. The highest C:N:P ratio was found in Paspalum repens which, during periods of drought, played an important role in releaseing nutrients into the water. The connectivity of the lake with the rivers ensured a high variation of transparency and nutrient content, fundamental for biological processes. A model of the nutrient flow, interaction and connectivity between ecosystems, and the influence of the hydrological cycle has been developed.

Information-Seeking on the Internet

Crisis ◽  
2015 ◽  
Vol 36 (3) ◽  
pp. 211-219 ◽  
Author(s):  
Vinod Singaravelu ◽  
Anne Stewart ◽  
Joanna Adams ◽  
Sue Simkin ◽  
Keith Hawton
Keyword(s):  
At Risk ◽  
Young People ◽  
Information Seeking ◽  
Significant Proportion ◽  
The Internet ◽  
Search Terms ◽  
Specific Advice ◽  
Restriction Sites ◽  
Self Harm ◽  
Negative Tone

Abstract. Background: The Internet is used by young people at risk of self-harm to communicate, find information, and obtain support. Aims: We aimed to identify and analyze websites potentially accessed by these young people. Method: Six search terms, relating to self-harm/suicide and depression, were input into four search engines. Websites were analyzed for access, content/purpose, and tone. Results: In all, 314 websites were included in the analysis. Most could be accessed without restriction. Sites accessed by self-harm/suicide search terms were mostly positive or preventive in tone, whereas sites accessed by the term ways to kill yourself tended to have a negative tone. Information about self-harm methods was common with specific advice on how to self-harm in 15.8% of sites, encouragement of self-harm in 7.0%, and evocative images of self-harm/suicide in 20.7%. Advice on how to get help was given in 56.1% of sites. Conclusion: Websites relating to suicide or self-harm are easily accessed. Many sites are potentially helpful. However, a significant proportion of sites are potentially harmful through normalizing or encouraging self-harm. Enquiry regarding Internet use should be routinely included while assessing young people at risk.

Searching Online for Methods of Suicide

Crisis ◽  
2020 ◽  
pp. 1-8
Author(s):  
Christian Ulrich Eriksen ◽  
Flemming Konradsen ◽  
Thilde Vildekilde
Keyword(s):  
Content Analysis ◽  
English Language ◽  
Significant Proportion ◽  
Background Information ◽  
Access To Information ◽  
Online Content ◽  
Negative Effects ◽  
Search Terms ◽  
Methods Of Suicide

Abstract. Background: Information on methods of suicide is available online, and access to information on methods of suicide appears to contribute to a small but significant proportion of suicides. There is limited documentation of how methods of suicide are being profiled, as well as what content exists in other languages than English. Aim: We aimed to analyze and compare how methods of suicide are profiled on Danish and English-language websites. Method: We applied a categorization and content analysis of websites describing methods of suicide. Sites were retrieved by applying widely used Danish and English-language search terms. Results: A total of 136 English-language websites and 106 Danish-language websites were included for analysis. Websites were more often categorized as prevention or support sites, academic or policy sites, and against suicide sites than dedicated suicide sites (i.e., pro-suicide sites), or information sites. However, information on methods of suicide was available, and 20.1% and 8.9% of the English and Danish-language sites, respectively, suggested that a particular method of suicide was quick, easy, painless, or certain to result in death. Limitations: Only one author coded and analyzed all websites. A further operationalization of the content analysis checklist is warranted to increase reliability. Conclusion: The websites primarily had a prevention or anti-suicide focus, but information on methods of suicide was available, requiring an increased focus on how to diminish the negative effects of harmful online content.

In Search of the Prosocial Personality

2019 ◽  
Vol 40 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Anja Wertag ◽  
Denis Bratko
Keyword(s):  
Prosocial Behavior ◽  
Personality Traits ◽  
Significant Proportion ◽  
Dark Triad ◽  
Self Report ◽  
Hierarchical Regression ◽  
Regression Analyses ◽  
The Relationship

Abstract. Prosocial behavior is intended to benefit others rather than oneself and is positively linked to personality traits such as Agreeableness and Honesty-Humility, and usually negatively to the Dark Triad traits (i.e., Machiavellianism, narcissism, and psychopathy). However, a significant proportion of the research in this area is conducted solely on self-report measures of prosocial behavior. Therefore, the aim of this study was to investigate the relationship between prosociality and the basic (i.e., HEXACO) and dark personality traits, comparing their contribution in predicting both self-reported prosociality and prosocial behavior. Results of the hierarchical regression analyses showed that the Dark Triad traits explain prosociality and prosocial behavior above and beyond the HEXACO traits, emphasizing the importance of the Dark Triad in the personality space.

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