Six common behavioral trials and their relevance for perch performance in natural lakes

AbstractObservations and modeling are used to assess potential impacts of sediment releases due to dam removals on the Hudson River estuary. Watershed sediment loads are calculated based on sediment-discharge rating curves for gauges covering 80% of the watershed area. The annual average sediment load to the estuary is 1.2 Mt, of which about 0.6 Mt comes from side tributaries. Sediment yield varies inversely with watershed area, with regional trends that are consistent with substrate erodibility. Geophysical and sedimentological surveys in seven subwatersheds of the Lower Hudson were conducted to estimate the mass and composition of sediment trapped behind dams. Impoundments were classified as (1) active sediment traps, (2) run-of-river sites not actively trapping sediment, and (3) dammed natural lakes and spring-fed ponds. Based on this categorization and impoundment attributes from a dam inventory database, the total mass of impounded sediment in the Lower Hudson watershed is estimated as 4.9 ± 1.9 Mt. This represents about 4 years of annual watershed supply, which is small compared with some individual dam removals and is not practically available given current dam removal rates. More than half of dams impound drainage areas less than 1 km2, and play little role in downstream sediment supply. In modeling of a simulated dam removal, suspended sediment in the estuary increases modestly near the source during discharge events, but otherwise effects on suspended sediment are minimal. Fine-grained sediment deposits broadly along the estuary and coarser sediment deposits near the source, with transport distance inversely related to settling velocity.

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Long-Term Changes in Floristic Diversity as an Effect of Transforming the Lake into a Retention Reservoir

Sustainability ◽

10.3390/su13147642 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7642

Author(s):

Joanna Sender ◽

Danuta Urban ◽

Monika Różańska-Boczula ◽

Antoni Grzywna

Keyword(s):

Drainage System ◽

High Water ◽

Diversity Indices ◽

Habitat Diversity ◽

Peat Bogs ◽

Ecological Index ◽

Natural Lakes ◽

Lighting Conditions ◽

Low Reaction Temperature

The Łęczna-Włodawa Lake District is one of the most valuable natural regions in Europe. It is an area of numerous lakes, peat bogs, swamps and forests, which has been undergoing intensive transformation for decades. Among the largest projects were the creation of the Wieprz Krzna Canal system along with the drainage system and the transformation of natural lakes into retention reservoirs. Among the transformed lakes is Lake Wytyckie. The land was used for analyses near the lake, and floristic and habitat analyses were carried out within the boundaries of the contemporary embankment. The studies were carried out from the 1950s, when the lake functioned as a natural reservoir, through to the 1980s (the transformation of the lake), to the 2020s. Lake Wytyckie was transformed into a retention reservoir by increasing its size and flooding the areas inhabited mainly by peat bog, meadow and forest vegetation, which contributed to the impoverishment of both species and habitat diversity of the area, while it increased the nutrient richness of the water. This was reflected both in the decline in the value of individual diversity indices as well as in the ecological index numbers. In the first period of the research, the area was dominated by wetlands, not drained, with a large variety of species that preferred good lighting conditions. Additionally, the habitat was characterized by low reaction, temperature and trophic values. In the following period, there was an increase in the depth of the water of the reservoir, characterized by high water visibility values, which contributed to the presence of protected species, as did the low moisture content of the areas within the embankment and a neutral pH. The factors currently influencing the formation of the vegetation structure are the high humidity of the entire embankment area, the increase in pH, and the significant increase in the share of built-up areas in the immediate vicinity.

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Water movements in lakes during summer stratification; evidence from the distribution of temperature in Windermere

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1952.0005 ◽

1952 ◽

Vol 236 (635) ◽

pp. 355-398 ◽

Cited By ~ 104

Keyword(s):

Internal Waves ◽

Mathematical Form ◽

Historical Survey ◽

Thermo Electric ◽

Stratified Lakes ◽

Natural Lakes ◽

Complicating Factors ◽

Internal Seiches ◽

Theoretical Analyses ◽

Scottish Lochs

The first part of this paper is taken up with an historical survey of the relatively few observations, some detailed and some less so, of internal seiches (internal standing waves) in lakes. After a description of the thermo-electric thermometer employed, there follow details and illustrations of the evidence, from temperature observations, for such internal waves in the northern basin of Windermere. Two main phases could be distinguished: (i) motion under wind stress leading to quasi-steady states with some or all of the isotherms tilted; (ii) internal seiche motion which developed after the wind had dropped. These observations confirm the findings of Wedderburn and his collaborators on the Scottish Lochs (1907-15). The results from Windermere are presented, not because any such confirmation is necessary, but in order to secure belated recognition of the fact that Wedderburn’s ‘ temperature seiche ’ is not an isolated phenomenon, but is an everyday feature of movement in stratified lakes subject to wind action. As this movement is an important and largely unrecognized factor in lake environment, this paper is addressed mainly to limnologists. In its latter part, results of theoretical analyses of a detailed series of observations are presented in non-mathematical form. The applicability of a theory of oscillations in a basin with three layers of differing density (set out in an appendix by M. S. Longuet-Higgins) is tested by comparing theoretical and observed deflexions of selected isotherms from their equilibrium levels, resulting from internal waves after a gale. This theory also enables horizontal components of velocity and displacement to be calculated for each layer. Complicating factors in natural lakes are enumerated, and the influence of internal waves on lake biology and sedimentation is discussed.

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Uzbekistan’s Aquatic Environment and Water Management as an Area of Interest for Hydrology and Thematic Tourism

Journal of Environmental Management and Tourism ◽

10.14505//jemt.v12.3(51).04 ◽

2021 ◽

Vol 12 (3) ◽

pp. 642

Author(s):

Jacek RÓŻKOWSKI ◽

Mariusz RZĘTAŁA

Keyword(s):

Water Management ◽

Agricultural Land ◽

Groundwater Resources ◽

Global Scale ◽

Aral Sea ◽

Irrigated Agriculture ◽

Human Consumption ◽

Irrigation Systems ◽

Natural Lakes ◽

Area Of Interest

The functioning of Uzbekistan’s economy is closely linked to the water resources of its huge cross-border rivers: the Amu Darya and the Syr Darya, as well as to the groundwater present within their basins. Both natural lakes and artificial reservoirs (e.g. the Aydar-Arnasay system of lakes, the Kayrakkum Reservoir, the Chardarya Reservoir) are present there, which retain significant amounts of water, and large canals with lengths of up to several hundred kilometres which involve complex hydraulic structures are used for irrigation purposes. All these are components of a water management system which needs optimisation; as much as 80% of agricultural land is irrigated, with 70% of the water being lost due to inefficient irrigation systems. The consequence of this allocation of river flows and the overuse of water in irrigation systems has been the disappearance of the Aral Sea (1960 year – 68,900 km2, 2017 year – 8,600 km2) and the inflow of water into the Sarygamysh Lake as well as the reduction of Uzbekistan’s groundwater resources by about 40%. The intensive development of irrigated agriculture is associated with changes in surface and groundwater quality caused, inter alia, by the increased use of chemicals in agriculture and the discharge of collector-drainage waters into river systems as well as their reuse. The extent of environmental degradation in some areas (especially in the Aral Sea region) is unique on a global scale. The origins of Uzbekistan’s other hydrological tourist attractions are related to attempts to ensure the availability of water for both human consumption and industrial use under conditions of water scarcity in the country’s arid and semi-arid climates. Not just the spectacular watercourses and water bodies present there (e.g. rivers, lakes, canals), but also small water retention facilities and minor infrastructure elements (e.g. wells, springs and retention basins, canals, ditches and flow control structures) are of potential tourist importance.

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Pretty Picky for a Generalist: Impacts of Toxicity and Nutritional Quality on Mantid Prey Processing

Environmental Entomology ◽

10.1093/ee/nvx038 ◽

2017 ◽

Vol 46 (3) ◽

pp. 626-632 ◽

Cited By ~ 2

Author(s):

Jamie L. Rafter ◽

Justin F. Vendettuoli ◽

Liahna Gonda-King ◽

Daniel Niesen ◽

Navindra P. Seeram ◽

...

Keyword(s):

C:N Ratio ◽

Danaus Plexippus ◽

Monarch Butterfly ◽

The Body ◽

Gut Contents ◽

Corn Borers ◽

Body Tissues ◽

Heterogeneous Quality ◽

Behavioral Trials

Abstract Prey have evolved a number of defenses against predation, and predators have developed means of countering these protective measures. Although caterpillars of the monarch butterfly,Danaus plexippus L., are defended by cardenolides sequestered from their host plants, the Chinese mantidTenodera sinensis Saussure guts the caterpillar before consuming the rest of the body. We hypothesized that this gutting behavior might be driven by the heterogeneous quality of prey tissue with respect to toxicity and/or nutrients. We conducted behavioral trials in which mantids were offered cardenolide-containing and cardenolide-freeD. plexippus caterpillars and butterflies. In addition, we fed mantids starved and unstarvedD. plexippus caterpillars from each cardenolide treatment and nontoxicOstrinia nubilalis Hübner caterpillars. These trials were coupled with elemental analysis of the gut and body tissues of bothD. plexippus caterpillars and corn borers. Cardenolides did not affect mantid behavior: mantids gutted both cardenolide-containing and cardenolide-free caterpillars. In contrast, mantids consumed bothO. nubilalis and starvedD. plexippus caterpillars entirely.Danaus plexippus body tissue has a lower C:N ratio than their gut contents, whileO. nubilalis have similar ratios; gutting may reflect the mantid’s ability to regulate nutrient uptake. Our results suggest that post-capture prey processing by mantids is likely driven by a sophisticated assessment of resource quality.

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Best Practices in Social and Behavioral Research: A multisite pilot evaluation of the good clinical practice online training course

Journal of Clinical and Translational Science ◽

10.1017/cts.2018.27 ◽

2018 ◽

Vol 2 (2) ◽

pp. 95-102 ◽

Cited By ~ 2

Author(s):

Susan L. Murphy ◽

Elias M. Samuels ◽

H. Robert Kolb ◽

Linda S. Behar-Horenstein ◽

Ellen Champagne ◽

...

Keyword(s):

Clinical Practice ◽

Best Practices ◽

Course Completion ◽

Online Training ◽

Good Clinical Practice ◽

Behavioral Research ◽

Future Studies ◽

Training Course ◽

Behavioral Trials ◽

Larger Sample

IntroductionThe Best Practices in Social and Behavioral Research Course was developed to provide instruction on good clinical practice for social and behavioral trials. This study evaluated the new course.MethodsParticipants across 4 universities took the course (n=294) and were sent surveys following course completion and 2 months later. Outcomes included relevance, how engaging the course was, and working differently because of the course. Open-ended questions were posed to understand how work was impacted.ResultsParticipants rated the course as relevant and engaging (6.4 and 5.8/7 points) and reported working differently (4.7/7 points). Participants with less experience in social and behavioral trials were most likely to report working differently 2 months later.DiscussionThe course was perceived as relevant and engaging. Participants described actions taken to improve rigor in implementing trials. Future studies with a larger sample and additional participating sites are recommended.

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Pengaruh Nitrat (NO3) Terhadap Pertumbuhan Alami Eceng Gondok (Eichornia crassipes Solms.) Berdasarkan Biomassa Basah Di Danau Batur, Kintamani, Bali

Journal of Marine and Aquatic Sciences ◽

10.24843/jmas.2017.v3.i02.215-222 ◽

2017 ◽

Vol 3 (2) ◽

pp. 215

Author(s):

Lisa Rosalia Prayuda ◽

I Wayan Arthana ◽

Ayu Putu Wiweka Krisna Dewi

Keyword(s):

Growth Rate ◽

Water Hyacinth ◽

High Fertility ◽

Natural Growth ◽

Initial Weight ◽

Daily Growth Rate ◽

Daily Growth ◽

Natural Lakes ◽

High Fertility Rate ◽

Eichornia Crassipes

Batur Lake is one of the natural lakes in the province of Bali where the activity of fishing, agriculture, tourism and housing available. This study aims to determine the effect of nitrate relation to the natural growth of the water hyacinth (Eichornia crassipes). Increased water hyacinth biomass in Songan station is the highest among the three other stations (Batur, Buahan, and Trunyan). At the end of the study (day 42 ), water hyacinth biomass of Songan station increased by 338.2 % from the initial weight, while at another station the increase weight ranges from 75 % -158 %. The highest daily growth rate in Trunyan station 3.68% / day, and the lowest in station Buahan which only reached 0.88% / day. At the Songan station where are many floating net which contribute to increase nitrate. There is a tendency of growth of water hyacinth faster at higher nitrate conditions. Nitrate conditions ranged from 0,35 to 0,62 m /l which shows that the waters of Batur Lake classified into waters that have a high fertility rate (eutrophic).

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Mortality of First-Feeding Postlarval Walleye (Stizostedion vitreum) in Culture Ponds

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f93-206 ◽

1993 ◽

Vol 50 (9) ◽

pp. 1835-1843 ◽

Cited By ~ 9

Author(s):

Thomas A. Johnston ◽

J. A. Mathias

Keyword(s):

Critical Period ◽

Mortality Rates ◽

Predation Pressure ◽

Stizostedion Vitreum ◽

Exogenous Feeding ◽

Natural Lakes ◽

First Feeding ◽

Zooplankton Density ◽

Food Concentrations ◽

Order Of Magnitude

We examined mortality rates of postlarval walleye (Stizostedion vitreum) at the onset of exogenous feeding in extensive culture ponds. Food concentrations (≥49 zooplankters∙L−1) were apparently sufficient to support successful first feeding, and no critical period of starvation mortality was evident at this stage of life. The highest observed mortality rates were associated with interspecific or intraspecific predation pressure. At low predation pressure, mean survival from stocking to the 12-mm stage was 87% in 1988 and 90% in 1989, and instantaneous mortality rates were an order of magnitude lower than those reported for postlarval walleye in natural lakes. Mortality rates calculated over the early postlarval period (stocking to 12 mm; 9–11 d) were similar to those calculated over the entire culture period (88–107 d) when predation pressure was low. At low predation pressure and 49–159 zooplankters∙L−1, there was no significant relationship between postlarval mortality rates and zooplankton density. The condition of first-feeding postlarvae captured from the pond with the lowest mean zooplankton density (49∙L−1) was significantly higher than that of postlarvae deprived of food for 48 h. Starvation is probably not a major cause of postlarval morality when zooplankton densities are ≥50∙L−1.

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