scholarly journals A Correlation Analysis between Physical Disturbance and Fish Habitat Suitability before and after Channel Structure Rehabilitation

2015 ◽  
Vol 2 (1) ◽  
pp. 33-41 ◽  
Author(s):  
Heung Sik Choi ◽  
Woong Hee Lee
2017 ◽  
Vol 1 (21) ◽  
pp. 49-63
Author(s):  
Zdzisław Kaliniewicz ◽  
Piotr Markowski ◽  
Andrzej Anders ◽  
Paweł Tylek ◽  
Zbigniew Krzysiak ◽  
...  

The basic dimensions and the mass of common beech nuts and seeds from five nut batches, harvested from tree stands in northern Poland, were determined. Environmental conditions had a greater influence on seed plumpness than the age of tree stands. The results of measurements were analyzed statistically by analysis of variance, correlation analysis and linear regression analysis. Despite differences in their plumpness, nuts were characterized by nearly identical cross-sections which resembled an equilateral triangle. The thickness of nuts and seeds was highly correlated with their mass, and this information can facilitate seed husking and separation into mass categories. Before and after husking, seeds should be separated with the use of a mesh screen with longitudinal openings. Medium-sized (most numerous) seeds were separated into the following plumpness categories using a screen separator with ≠6 mm and ≠7 mm openings: 84% of moderately plump seeds, 3% of seeds with reduced plumpness, and 13% of plump seeds.


2021 ◽  
Vol 13 (8) ◽  
pp. 4330
Author(s):  
Byungwoong Choi ◽  
Seung Se Choi

Recent ecological stream restoration projects have focused on expanding the water-friendly space of streams, promoting the health of aquatic ecosystems, and restoring various habitats, which raise the need for relevant research. Applying integrated environmental analysis, this study quantifies the change in hydraulic characteristics before and after the restoration projects through physical habitat simulation and links the results of physical impacts to estimate benefits of increase in water quality and aquatic ecosystem health due to the implementation of the project. For this, the study area is a 3.3 km long reach of the Anyang-cheon Stream, Korea. Field monitoring revealed that five fish species are dominant and sub-dominant, and account for 76% of the total fish community. To assess the change of before and after ecological stream restoration project, the River2D and Coastal Modelling System (CMS)-Flow 2D models were used for hydraulic and water quality simulations, respectively. For the habitat simulation, the HSI (Habitat Suitability Index) model was used. In addition, the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) was used to calculate changes in water quality index and to examine changes in habitat areas with an integrated quantitative index, the methodology of Zingraff-Hamed et al. was adopted. It was found that the ecological stream restoration project significantly increased for the eco-friendly area. In addition, the changes in water quality and habitat suitability grades before the ecological river restoration project were improved to two stages and one stage, respectively. This study applied the integrated analytical framework as a policy/project assessment tool and the results of this study will be useful for the integrated water management policy.


2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Ryan L. S. Sharpe ◽  
Mufti Mahmud ◽  
M. Shamim Kaiser ◽  
Jianhui Chen

AbstractHere we provide evidence with an exploratory pilot study that through the use of a Gamma 40 Hz entrainment frequency, mood, memory and cognition can be improved with respect to a 9-participant cohort. Participants constituted towards three binaural entrainment frequency groups: the 40 Hz, 25 Hz and 100 Hz. Participants attended a total of eight entrainment frequency sessions twice over the duration of a 4-week period. Additionally, participants were assessed based on their cognitive abilities, mood as well as memory, where the cognitive and memory assessments occurred before and after a 5-min binaural beat stimulation. The mood assessment scores were collected from sessions 1, 4 and 8, respectively. With respect to the Gamma 40 Hz entrainment frequency population, we observed a mean improvement in cognitive scores, elevating from 75% average to 85% average upon conclusion of the experimentation at weak statistical significance ($$\alpha$$ α = 0.10, p = 0.076). Similarly, memory score improvements at a greater significance ($$\alpha$$ α = 0.05, p = 0.0027) were noted, elevating from an average of 87% to 95%. In pertinence to the mood scores, a negative correlation across all populations were noted, inferring an overall increase in mood due to lower scores correlating with elevated mood. Finally, correlation analysis revealed a stronger R$$^2$$ 2 value (0.9838) within the 40 Hz group between sessions as well as mood score when compared across the entire frequency group cohort.


2020 ◽  
Vol 22 ◽  
pp. e01023
Author(s):  
Dinesh Neupane ◽  
Youngsang Kwon ◽  
Thomas S. Risch ◽  
Ronald L. Johnson

2019 ◽  
Author(s):  
Hyeon Jeong Yoon ◽  
Jonghwa Kim ◽  
Sang Woo Park ◽  
Hwan Heo

Abstract Background To investigate differences in refraction, accommodative factors, ocular parameters, and subjective symptoms after using two types of virtual reality (VR) content with different perception depths. Methods Twenty-three volunteers, who played VR games in two modes (immersive and non-immersive) for 30 min, were enrolled. Ocular parameters were examined before and after using VR. Accommodative factors were measured using static and dynamic methods, and subjective symptoms were assessed using a questionnaire. Differences according to VR content and correlations between each ocular parameter were analyzed. Results There were no changes in refraction and accommodative factors after use of the VR. However, there was a significant increase in near point accommodation (NPA), near point convergence (NPC), and subjective symptom scores after using the immersive mode. Correlation analysis revealed that NPA and accommodative lag were increased in subjects with exophoria, and that subjects with high NPA or NPC were more likely to exhibit an increase in mean accommodative lag. Conclusions The use of VR for 30 min reduced NPA and NPC especially after the immersive mode was used. In addition, using VR could further increase accommodation lag and reduce the amplitude of accommodation and convergence in subjects with exophoria.


2020 ◽  
Vol 10 (4) ◽  
pp. 94
Author(s):  
Suwakhon Phakeewai ◽  
Prayoon - Wongchantra

This research aims to develop the environmental recreation camp activity for youth in Roi-Et province of Thailand, to compare environmental knowledge, environmental attitudes before and after participating in the camp, as will as their participating in Environment Recreation camp activities during and after participating in the camp of youths with different gender and domicile, and to study the relationship between environmental knowledge, environmental attitudes and participation in environmental recreation camp activities. The data were collected though a survey with 40 youths from Phanom Phrai Wittayakarn School, Phanom Phrai District, Roi-Et Province. The research instruments was the manuals questionnaire measuring environmental knowledge, environmental attitudes and participation in environmental recreation camp activity. The data were analysed by using descriptive statistic and hypothesis testing by using t-test, One-way MANCOVA, One-way ANOVA and Correlation analysis. The results of this research indicated as below Environment Recreation Camp Activities for Youth in Roi-Et Province had effectively is 85.17/83.44 and an effectiveness index is 0.6117. After participating in environment recreation camp activities, youths had higher environmental knowledge and environmental attitudes than before participating in the camp. After participating in environment recreation camp activities, youth had higher participation in environment recreation camp activities than during participating in camp. The sample youths with different gender and domicile had no different environmental knowledge, environmental attitudes, and environmental participation. Environmental knowledge, environmental attitudes, and participation in environmental recreation camp activities were not correlated.


<em>Abstract</em> .—Basic research on the settlement and postsettlement ecology of spiny lobster <em>Panulirus argus </em> has led to an application with the potential to replace lost natural refuge with artificial shelters intended for the vulnerable small juvenile stages. We began investigating ecological processes regulating juvenile spiny lobster recruitment in the Florida nursery in the mid-1980s. An unprecedented massive die-off of sponges in the middle Florida Keys followed cyanobacterial blooms in 1991–1993, ultimately affecting about 300 km2 of a region providing approximately one-fifth of total juvenile recruitment. Before 1991, crevices in sponges provided diurnal refuge from predators for about 70% of juveniles <50 mm carapace length. On the basis of sampling done before and after sponge loss, we estimated that juvenile abundance declined by 30–50% on spongeless sites without alternative shelter, resulting in a decrease of annual nurserywide potential of up to 10%. Results of a field experiment evaluating the relative influences of the magnitude of settlement and availability of crevice shelter on juvenile recruitment, fortuitously begun before the sponge die-off, showed that juvenile survival and abundance were sustained on small 0.02- to 0.07-ha test sites provided with supplemental artificial shelters (slotted concrete blocks). In the absence of sponges, survival of microwire-tagged juveniles on the shelter-supplemented sites was about six times higher than that on unsupplemented sites. On the basis of our earlier ecological findings, we devised a feasibility study to test whether the artificial shelters could replace lost sponge shelter for juvenile lobsters on a large scale. It took the form of a field experiment using 240 shelters spread over 1-ha sites located amid hard substrate denuded of sponges. The shelters provided substitute crevices, supporting juvenile lobster recruitment approximating that in areas with good sponge cover. This outcome exemplifies the essential value of initial basic research that provides understanding of the ecological processes regulating individual survival and, ultimately, the character and dynamics of the fishery population. Such an approach, and the information it provides, is necessary to successful rehabilitation of essential habitat or restocking of natural populations. Moreover, conducting basic research can help prevent the waste of precious time, funds, income, and human effort that typically has occurred in past failed attempts that were undertaken with insufficient knowledge. We urge the fisheries-ecology discipline and support agencies to promote strongly the primacy of research on basic processes.


<em>Abstract.—</em> A need exists to scientifically determine optimal fish habitats to support decision making for management of essential fish habitat. Scientists have been collaborating to conduct habitat suitability index (HSI) modeling to spatially delineate fish habitats for estuarine fish and invertebrate species in Tampa Bay and Charlotte Harbor, Florida. Results from HSI modeling of juvenile spotted seatrout <em>Cynoscion nebulosus </em> in Charlotte Harbor are presented. Data obtained from 1989–1997 by fisheries-independent monitoring in the two estuaries were used along with environmental data from other sources. Standardized catch-per-unit-effort (catch rates) were calculated across gear types using fisheries-monitoring data from Charlotte Harbor and Tampa Bay. Suitability index functions were determined using three methods: (1) frequency of occurrence, (2) mean catch rates within ranges, and (3) smooth-mean catch rates determined by polynomial regression. Mean catch rates were estimated within biologically relevant ranges and, where sufficient data were available, for finer intervals across environmental gradients. Suitability index functions across environmental gradients were then derived by scaling catch rates. Gridded habitat layers for temperature, salinity, depth, and bottom type in Charlotte Harbor were also created using a geographic information system. Habitat suitability index modeling was conducted using the U.S. Fish and Wildlife Service geometric mean method linked to the ArcView Spatial Analyst module. The model integrated suitability indices associated with the habitat layers for Charlotte Harbor to create a map of the predicted distribution for juvenile spotted seatrout during the fall season. Suitability indices developed for Tampa Bay were used with Charlotte Harbor habitat layers to test transfer of the indices to another estuary. Predicted HSI maps depicted low to optimum habitat suitability zones in Charlotte Harbor. Model performance was evaluated by statistically comparing the relative ranking of mean catch rates with mean suitability indices for corresponding zones. Suitability indices obtained using polynomial regression methods yielded morereliable HSI maps for juvenile spotted seatrout than those derived using mean catch rates within biologically relevant ranges. The observed map, derived using smooth-mean suitability indices transferred from Tampa Bay, was not significantly different (Chi-square goodness-of-fit test) from the expected map derived using smooth-mean indices from Charlotte Harbor. Our modeling efforts using transferred indices indicate that it is possible to predict the geographic distributions of fish species by life stage in estuaries lacking fisheries monitoring.


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