Hydropeaking by Small Hydropower Facilities Affects Flow Regimes on Tributaries to the Pantanal Wetland of Brazil

Hydroelectric facilities often release water at variable rates over the day to match electricity demand, resulting in short-term variability in downstream discharge and water levels. This sub-daily variability, known as hydropeaking, has mostly been studied at large facilities. The ongoing global proliferation of small hydropower (SHP) facilities, which in Brazil are defined as having installed capacities between 5 and 30 MW, raises the question of how these facilities may alter downstream flow regimes by hydropeaking. This study examines the individual and cumulative effects of hydropower facilities on tributaries in the upland watershed of the Pantanal, a vast floodplain wetland system located on the upper Paraguay River, mostly in Brazil. Simultaneous hourly discharge measurements from publicly available reference and downstream gage stations were analyzed for 11 reaches containing 24 hydropower facilities. Most of the facilities are SHPs and half are run-of-river designs, often with diversion channels (headraces). Comparison of daily data over an annual period, summarized by indicators of hydrological alteration (HA) that describe the magnitude, frequency, rate of change, and duration of flows, revealed differences at sub-daily scales attributable to hydropeaking by the hydropower facilities. Results showed statistically significant sub-daily HA in all 11 reaches containing hydropower facilities in all months. Discharge indicators that showed the highest percentage of days with increased variability were the mean rates of rise and fall, amplitude, duration of high pulses, maximum discharge, and number of reversals. Those that showed higher percentages of decreased variability included minimum discharge, number of high pulses, duration of stability, and number of low pulses. There was no correlation between HA values and physical characteristics of rivers or hydropower facilities (including installed capacity), and reaches with multiple facilities did not differ in HA from those with single facilities. This study demonstrates that SHPs as well as larger hydropower facilities cause hydrological alterations attributable to hydropeaking. Considering the rapid expansion of SHPs in tropical river systems, there is an urgent need to understand whether the ecological impacts of hydropeaking documented in temperate biomes also apply to these systems.

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Comprehensive assessment of the citizen wellbeing in the territory of residence: taking into account the changing influence of indicators economic security

Level of Life of the Population of Regions of Russia ◽

10.19181/lsprr.2021.17.4.6 ◽

2021 ◽

Vol 17 (4) ◽

pp. 491-502

Author(s):

Alexsandr Kuklin ◽

Sergey Okhotnikov

Keyword(s):

Spiritual Development ◽

Diagnostic Technique ◽

Federal District ◽

Well Being ◽

Economic Security ◽

Rate Of Change ◽

Degree Of Satisfaction ◽

Current Assessment ◽

The Subject ◽

The Individual

The article considers a generalizing characteristic of the citizen's wellbeing in the territory of residence, assesses indicators based on statistical data, and makes adjustments due to safety indicators. The author's diagnostic technique was used, which includes corrective indicators. For this purpose, the method of express diagnostics was applied, which made it possible to select the 8 most significant from 12 modules and 43 indicators of economic security. The rate of change of each of the 8 indicators was taken into account, which made it possible to determine the changes in these indicators and the predisposition to one degree or another of the socio-economic crisis. A change in the trend of an indicator can lead to the opposite effect at the expense of other main influencing indexes. This takes into account the borderline state of the indicator, namely, its rate of growth or decline and predisposition to a particular crisis zone. The turning zones of the trend of changes in indicators have been determined. The object of the research is the well-being of the individual in the territory of residence for each subject of the Ural Federal District. The authors made an attempt to consider in the analysis not just the population of the subject (the number of people), but also to assess the personality from the standpoint of moral development, the level of education, the available opportunities for spiritual development, the provision of benefits necessary to maintain life and the degree of satisfaction of the needs of the population. This will allow to carry out the current analysis of the state, but also to consider the forecast dynamics of change for the next 2 to 3 years. The results obtained can be used in the current assessment of the socio-economic situation in the regions of Russia, as well as in planning and forecasting individual indicators of individual citizen wellbeing in the territory of residence

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Mollusc fisheries and length–weight relationship in Tonle Sap flood pulse system, Cambodia

Annales de Limnologie - International Journal of Limnology ◽

10.1051/limn/2018026 ◽

2018 ◽

Vol 54 ◽

pp. 34 ◽

Cited By ~ 5

Author(s):

Peng Bun Ngor ◽

Ratha Sor ◽

Leang Hour Prak ◽

Nam So ◽

Zeb S. Hogan ◽

...

Keyword(s):

Annual Variation ◽

Flood Pulse ◽

Growth Patterns ◽

Water Levels ◽

Relationship Analysis ◽

Weight Relationship ◽

Daily Data ◽

Tonle Sap ◽

Mollusc Species ◽

One Year

Molluscs are important for ecological function, livelihoods and fisheries, but are often forgotten in research and management. Here, we investigated intra-annual variation in the landing and growth patterns of three mollusc species, i.e., Corbicula moreletiana, Pila virescens and Pila ampullacea, using one-year daily data on landing catches and values, recorded in Kampong Chhnang province of Tonle Sap (TS) Lake. Overall, 8330 tonnes with a first sale landing value of US$ 1.4 million for the three species were reported. Also, we found that C. moreletiana was abundant during the dry season with high temperature and less precipitation. By contrast, the two Pila species were abundant from the early rainy to early dry seasons when precipitation and water levels increase. The length–weight relationship analysis indicated that a faster growth in weight of Pila species occurred in the rainy season, and a general negative allometric growth was observed for the three species. This implies that their populations were intensively fished. Our preliminary results suggest that molluscs in the TS Lake (i) are important resources in support of people's livelihoods, (ii) respond differently to intra-annual variation in temperature, precipitation and hydrology and (iii) are being intensively exploited with significant reduction in growth rate. Therefore, it is necessary to conduct further comprehensive research describing status of mollusc stocks and their ecology to support long-term management and conservation of this important aquatic fauna. Our study contributes to establishing the first important baseline data and information on key mollusc species for the TS.

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Technospherization and Digitalization of the Urban Habitat as the Most Urgent Factor in the Relevancy of Social Pedagogy Modernization

SHS Web of Conferences ◽

10.1051/shsconf/20219305012 ◽

2021 ◽

Vol 93 ◽

pp. 05012

Author(s):

Taisiya Kolesnik ◽

Elena Dergacheva

Keyword(s):

Rate Of Change ◽

Urban Habitat ◽

Negative Effects ◽

Socialization Process ◽

Education Development ◽

Natural Approach ◽

Social Pedagogy ◽

Other Information ◽

Mechanisms Of Adaptation ◽

The Individual

The processes of socialization of the individual in the conditions of substitution of the biosphere by the technosphere are analyzed. It is concluded that the rapid rate of change is aligned with the evolutionarily developed mechanisms of adaptation. This causes deterioration of human health and results in the inability of people to protect themselves from the negative effects of the anthropogenic world. At this conjuncture, the correction of the processes of socialization and adaptation, as well as the development of a system of values that provides for preserving of the biosphere world and life, become the fundamental tasks of education. The results of the analysis show that modern education is losing traction in the process of mindset formation, delegating these functions to other information spheres, virtual reality, and spontaneous areas of Masscult. As a result, the traditional socialization process is broken. Humane correction of the current trends requires a change in the philosophical strategy of education development. As a basis for such a strategy, we propose social pedagogy that directly studies the processes of socialization of individuals. The concept of this discipline allows using the socio-natural approach as the basis for analyzing the processes, taking place in the world and in life.

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Changes in composition of aquatic bird assemblages associated with changing in water levels in the Aquatic Terrestrial Transitional Zone of the Pantanal wetland Brazil

Research Society and Development ◽

10.33448/rsd-v9i10.8555 ◽

2020 ◽

Vol 9 (10) ◽

pp. e4479108555

Author(s):

Josué Ribeiro da Silva Nunes ◽

Carolina Joana da Silva ◽

Solange Kimie Ikeda-Castrillon ◽

Nilo Leal Sander

Keyword(s):

Aquatic Macrophyte ◽

Transitional Zone ◽

High Water ◽

Flood Pulse ◽

Water Levels ◽

Aquatic Birds ◽

Mato Grosso ◽

Paraguay River ◽

The Difference ◽

Pantanal Wetland

The Pantanal wetland Mato Grosso, Brazil is among the largest floodplains in the world, with a mosaic of different habitats and rich aquatic and terrestrial biota. The habitat mosaics are found in the Chacororé and Sinhá Mariana lake System. These parental lakes of the Cuiabá River, a left tributary of the Upper Paraguay River, are known for their aquatic productivity and scenic beauty. The characteristics of these lakes and their floodplains are showed through the difference between their waters, the diversity of the aquatic macrophytes communities, fish communities and aquatic birds. Our study looked at changes in limnological variables as well as diversity of aquatic birds, during high water or flooded phase; medium water or receding phase; and the low water or dry phase. We used a temporary small lagoon in the floodplain of this system as our study area. The flood pulse is the main ecological factor affecting the Pantanal; it modifies ecological process and species composition. The water depth decreases during the season, decreasing electrical conductivity, dissolved phosphate and nitrate, water transparency, dissolved oxygen and biomass of aquatic macrophyte; and increasing calcium, total phosphorus and total nitrogen. We also observed increase in species richness and abundance of aquatic birds during the receding phase. Results show that the number of species (density) of aquatic birds increased from 10 to 30 species and the numbers of individuals from 40 to 936. The maximum richness and abundance of aquatic birds was registered during the receding phase.

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Doppler Shift of Radio Signals Transmitted between Orbiting Satellites

Australian Journal of Physics ◽

10.1071/ph820155 ◽

1982 ◽

Vol 35 (2) ◽

pp. 155 ◽

Cited By ~ 1

Author(s):

PL Dyson ◽

JA Bennett

Keyword(s):

Electron Concentration ◽

Doppler Shift ◽

Rate Of Change ◽

Line Of Sight ◽

Concentration Gradients ◽

Mean Velocity ◽

Radio Signals ◽

The Mean ◽

The Moment ◽

The Individual

A general expression, applicable at VHF and above, is derived for the Doppler shift of radio signals transmitted between two satellites embedded in the ionosphere. The Doppler shift is made up of several contributions which depend on (a) the rate of change of the free space path between the satellites, (b) the components, perpendicular to the line of sight between the satellites, of both the mean velocity of the satellites and the electron concentration gradients, (c) the moment of the perpendicular electron concentration gradients and the deviations from the mean of the individual satellite perpendicular velocities, (d) the velocity components along the line of sight between the satellites, and the electron concentration values at each satellite, and (e) changes occurring in the ionosphere with time.

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Change of Phototropic and Geotropic Signs in Daphnia Induced by Changes of Light Intensity

Journal of Experimental Biology ◽

10.1242/jeb.7.2.109 ◽

1930 ◽

Vol 7 (2) ◽

pp. 109-131 ◽

Cited By ~ 2

Author(s):

G. L. CLARKE

Keyword(s):

Light Intensity ◽

Latent Period ◽

Daphnia Pulex ◽

Great Majority ◽

Absolute Intensity ◽

Rate Of Change ◽

Intensity Change ◽

The Difference ◽

The Individual ◽

Secondary Signs

1. A method is described for studying the responses of Daphnia to changes of light intensity with special attention to the behaviour of the individual and to the avoidance of "shock" effects. The types of apparatus used provide for rigid control of the temperature, for illumination from any direction, and for an adjustable rate of change of the light intensity by means of a chemical rheostat. 2. The great majority of Daphnia magna and Daphnia pulex were found to be primarily negatively phototropic and positively geotropic. That is, they always exhibited those tropistic signs under constant conditions of illumination. 3. A reduction of the light intensity causes a temporary reversal of the tropism signs. The secondary signs thus produced are positive phototropism and negative geotropism. 4. The presence of both phototropic and geotropic forces is proved by experiments in which illumination is (1) from one side, (2) from beneath, and (3) from two opposing sides or from above and below simultaneously. In these tests and in others in which very slow and very fast rates of dimming are used the phototropic and geotropic forces are resolved, antagonised, and neutralised in succession. The responses of the Daphnia indicate that there are two types of animals which exhibit exactly the same tropisms, but in one type phototropism is the stronger while in the other geotropism is the stronger. 5. In this material it was found that the temporary secondary tropistic signs persisted only a few minutes while the primary signs persisted for hours, although this effect was somewhat less marked in weak light or in darkness. 6. The difference between "time-change" and "place-change" of light in tensity is pointed out. Daphnia is stimulated by both types of change if the rate of change is sufficiently great. 7. That photosensitive animals are stimulated to respond to changes in the intensity of light only and are merely orientated by the direction of the light is shown in the work of previous, investigators as well as in this paper. The rigidity of this mechanism is indicated by experiments in which the light is graded in intensity at right angles to its direction and in which the light is rendered converging and diverging by a lens. 8. Evidence is given for believing that there is no "absolute optimum" light intensity for Daphnia but that a "relative optimum" exists which is the intensity to which the animals are adapted at the moment. 9. The interval between the inception of the reduction of the light intensity and the beginning of swimming movements in response is called the latent period. The faster the rate of dimming, the shorter is the duration of the latent period. A minimum, amount of intensity change is required to produce any response, at any speed, but beyond that the slower the rate of dimming, the greater is the amount of change required and hence the lower is the absolute intensity at which the response takes place. Ordinarily, the response is maximal in respect to both rate and magnitude. 10. Fatigue will interfere with experimentation unless guarded against. 11. Specimens of Daphinia with reversed primary signs gain temporary secondary signs following an increase of light intensity; otherwise they behave like the more usual forms. 12. The possibility that the processes of adaptation in Daphnia may account for the photic responses observed is discussed. Support for this theory is derived from the fact that it is possible to dim the light over a given range at such a slow rate that no response is produced.

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The Effect of Total Precipitation of Various Periods to Flow Regimes in Mountainous Catchments in Japan : Considering the Geological Characteristics of Catchments

10.5194/egusphere-egu21-14051 ◽

2021 ◽

Author(s):

Yuka Muto ◽

Takeyoshi Chibana ◽

Masafumi Yamada

Keyword(s):

Sedimentary Rocks ◽

Correlation Coefficients ◽

Flow Regimes ◽

Rate Of Change ◽

Total Precipitation ◽

Lower Type ◽

Geological Characteristics ◽

Mountainous Catchments ◽

Geological Conditions ◽

The Difference

In order to conduct an appropriate management in each catchment, it is important to understand how the difference in geological conditions affect the relationship between precipitation and flow regimes.Considering the differences in geological characteristics of catchments, this study aims 1)to clarify the period for calculating the total precipitation that is most influential to several levels of daily flow respectively and 2)to clarify the contribution of the change in the total precipitation of &#8216;the most influential period&#8217; to the change in flow.In this study, 63 mountainous catchments (dam catchments) within the Japanese Archipelago were selected as target areas. First, the 63 catchments were divided into 4 groups according to their geological characteristics. Second, from the observed data of daily flow lasting 26 years (from 1993 to 2018), 6 types of daily flow which represent flow of different scales within a year (1, 10, 25, 50, 75, 95 percentiles of daily flow within a year) were searched. In each geological classification, correlation coefficients between each 6 type of flow and total precipitation of various periods (from 2 days to 365 days) were calculated. Finally, for each geological classification and each type of flow, single regression analyses were conducted, setting the rate of change in flow amount as the objective variable, and the rate of change in total precipitation amount of the appropriate period as the explanatory variable.As a result, in the analysis of correlation coefficients, significant differences among different geological classifications were seen for lower type of flows but not for higher type of flows. For catchments of volcanic rocks in the Quaternary period, total precipitation of 365 days before the flow occurrence had the highest correlation coefficient with lower type of flows. On the other hand, for catchments of sedimentary rocks in the Mesozoic or Paleozoic era, the most influential period was approximately 45 days, which was the shortest.Also, increasing trends in flow (i.e. the rate of change in flow > 1.0) during the target period were seen regardless of the geological classification or the type of flow. However, from the simple regression analysis, the significant effect of the change in precipitation to the change in flow was only seen for annual maximum flow of catchments of sedimentary rocks from the Mesozoic or Paleozoic era. Except this specific geological characteristic and flow type, there is a possibility that other conditions of the catchments (e.g. change in land use) have larger effect to the change in flow compared to the change in precipitation.In the analyses mentioned above, the effect of snowfall is not considered. Therefore, in the presentation, the difference between snow covered regions and others are compared in addition.

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Response of wild mammals to seasonal shrinking-and-expansion of habitats due to flooding regime of the Pantanal, Brazil

Brazilian Journal of Biology ◽

10.1590/s1519-69842006000600006 ◽

2006 ◽

Vol 66 (4) ◽

pp. 991-998 ◽

Cited By ~ 16

Author(s):

S. B. Mamede ◽

C. J. R. Alho

Keyword(s):

Dry Season ◽

Water Levels ◽

Wild Mammals ◽

Flooding Regime ◽

Terrestrial Mammals ◽

Paraguay River ◽

Terrestrial Habitats ◽

Slow Moving ◽

Blastocerus Dichotomus ◽

Seasonally Flooded

The Pantanal is a large savanna wetland (138,183 km² in Brazil), important for its wildlife, fed by tributaries of the upper Paraguay River, center of South America (Brazil, touching Bolivia and Paraguay). Uplands are plateaus (250-1,200 m high, 215,000 km² in Brazil) and flatland is the Pantanal (80-150 m high, 147,574 km² in Brazil). Rivers are slow moving when they meet the flatland (slope 0.3-0.5 m/km east-west; 0.03-0.15 m/km north-south), periodically overflowing their banks, creating a complex seasonal habitat range. Recurrent shallow flooding occupies 80% of the Pantanal; during the dry season flooded areas dry up. Fluctuating water levels, nutrients and wildlife form a dynamic ecosystem. A flooding regime forms distinct sub-regions within the Pantanal. A mammal survey was carried out in the sub-region of the Rio Negro from April, 2003 through March, 2004 to study the diversity and abundance of terrestrial mammals during the dry and flooding seasons. A total of 36 species were observed in the field. The capybara Hydrochaeris hydrochaeris was the most frequent species, followed by the crab-eating-fox Cerdocyon thous and the marsh deer Blastocerus dichotomus. The highest abundance of species was observed during the dry season (August and September), when there is a considerable expansion of terrestrial habitats, mainly seasonally flooded grassland. Animal abundance (in terms of observed individual frequencies) varied during the dry and wet seasons and the seasonally flooded grassland was the most utilized habitat by mammals in the dry season.

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The Role of Coping Strategies in Maintaining Well-Being During the COVID-19 Outbreak in South Korea

Social Psychological and Personality Science ◽

10.1177/1948550621990595 ◽

2021 ◽

pp. 194855062199059

Author(s):

Joo Hyun Kim ◽

Yerin Shim ◽

Incheol Choi ◽

Eunsoo Choi

Keyword(s):

South Korea ◽

Coping Strategies ◽

Growth Models ◽

Phase 1 ◽

Well Being ◽

Rate Of Change ◽

Phase 2 ◽

Behavioral Strategies ◽

The Individual

The COVID-19 pandemic continues to pose an unprecedented challenge for the world as people strive to cope with this significant threat to their well-being. This intensive longitudinal study of the first 94 days of the COVID-19 outbreak in South Korea (Phase 1: initial outbreak, Phase 2: intense social distancing) examined individuals’ changes in well-being, in relation to their use of coping strategies and fear of infection. A sample of 10,464 South Koreans participated in surveys during Phase 1 and Phase 2, resulting in 35,846 observations. Multilevel growth models revealed a decrease in well-being while different coping strategies moderated the individual rate of change in well-being. Although preventive measures were associated with a greater decrease in well-being, cognitive appraisal and behavioral strategies predicted stable well-being during the pandemic. Coping strategies further mediated the association between fear of infection and deterioration of well-being.

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Network models for ponding on sea ice

10.5194/egusphere-egu2020-10021 ◽

2020 ◽

Author(s):

Michael Coughlan ◽

Ian Hewitt ◽

Sam Howison ◽

Andrew Wells

Keyword(s):

Sea Ice ◽

Network Models ◽

Pond Water ◽

Arctic Sea Ice ◽

Water Levels ◽

Catchment Basin ◽

Sea Ice Extent ◽

Albedo Feedback ◽

Catchment Areas ◽

The Individual

Arctic sea ice forms a thin but significant layer at the ocean surface, mediating key climate feedbacks. During summer, surface melting produces considerable volumes of water, which collect on the ice surface in ponds. These ponds have long been suggested as a contributing factor to the discrepancy between observed and predicted sea ice extent. When viewed at large scales ponds have a complicated, approximately fractal geometry and vary in area from tens to thousands of square meters. Increases in pond depth and area lead to further increases in heat absorption and overall melting, contributing to the ice-albedo feedback.Previous modelling work has focussed either on the physics of individual ponds or on the statistical behaviour of systems of ponds. We present a physically-based network model for systems of ponds which accounts for both the individual and collective behaviour of ponds. Each pond initially occupies a distinct catchment basin and evolves according to a mass-conserving differential equation representing the melting dynamics for bare and water-covered ice. Ponds can later connect together to form a network with fluxes of water between catchment areas, constrained by the ice topography and pond water levels.We use the model to explore how the evolution of pond area and hence melting depends on the governing parameters, and to explore how the connections between ponds develop over the melt season. Comparisons with observations are made to demonstrate the ways in which the model qualitatively replicates properties of pond systems, including fractal dimension of pond areas and two distinct regimes of pond complexity that are observed during their development cycle. Different perimeter-area relationships exist for ponds in the two regimes. The model replicates these relationships and exhibits a percolation transition around the transition between these regimes, a facet of pond behaviour suggested by previous studies. Our results reinforce the findings of these studies on percolation thresholds in pond systems and further allow us to constrain pond coverage at this threshold - an important quantity in measuring the scale and effects of the ice-albedo feedback.

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