scholarly journals Temporal Effects of Groundwater on Physical and Biotic Components of a Karst Stream

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1299 ◽  
Author(s):  
Tao Tang ◽  
Shuhan Guo ◽  
Lu Tan ◽  
Tao Li ◽  
Ryan M. Burrows ◽  
...  
Keyword(s):  
Water Temperature ◽  
Algal Biomass ◽  
Groundwater Discharge ◽  
Stream Network ◽  
Lotic Ecosystems ◽  
Chl A ◽  
Discharge Water ◽  
Downstream Reach ◽  
Insight Into

Although most lotic ecosystems are groundwater dependent, our knowledge on the relatively long-term ecological effects of groundwater discharge on downstream reaches remains limited. We surveyed four connected reaches of a Chinese karst stream network for 72 consecutive months, with one reach, named Hong Shi Zi (HSZ), evidently affected by groundwater. We tested whether, compared with other reaches, HSZ had (1) milder water temperature and flow regimes, and (2) weaker influences of water temperature and flow on benthic algal biomass represented by chlorophyll a (Chl. a) concentrations. We found that the maximum monthly mean water temperature in HSZ was 0.6 °C lower than of the adjacent upstream reach, and the minimum monthly mean water temperature was 1.0 °C higher than of the adjacent downstream reach. HSZ had the smallest coefficient of variation (CV) for water temperature but the largest CV for discharge. Water temperature and discharge displayed a significant 12-month periodicity in all reaches not directly groundwater influenced. Only water temperature displayed such periodicity in HSZ. Water temperature was an important predictor of temporal variation in Chl. a in all reaches, but its influence was weakest in HSZ. Our findings demonstrate that longer survey data can provide insight into groundwater–surface water interactions.

scholarly journals Long-Term Water Quality Patterns in an Estuarine Reservoir and the Functional Changes in Relations of Trophic State Variables Depending on the Construction of Serial Weirs in Upstream Reaches

2021 ◽  
Vol 18 (23) ◽  
pp. 12568
Author(s):  
Namsrai Jargal ◽  
Ho-Seong Lee ◽  
Kwang-Guk An
Keyword(s):  
Water Quality ◽  
Organic Matter ◽  
Algal Biomass ◽  
Trophic State ◽  
Suspended Solids ◽  
State Variables ◽  
Chl A ◽  
Functional Changes ◽  
Estuarine Reservoir

Water quality degradation is one of the major problems with artificial lakes in estuaries. Long-term spatiotemporal patterns of water quality in a South Korean estuarine reservoir were analyzed using seasonal datasets from 2002 to 2020, and some functional changes in relations of trophic state variables due to the construction of serial weirs in the upper river were also investigated. A total of 19 water quality parameters were used for the study, including indicators of organic matter, nutrients, suspended solids, water clarity, and fecal pollution. In addition, chlorophyll-a (CHL-a) was used to assess algal biomass. An empirical regression model, trophic state index deviation (TSID), and principal component analysis (PCA) were applied. Longitudinal fluctuations in nutrients, organic matter, sestonic CHL-a, and suspended solids were found along the axis of the riverine (Rz), transition (Tz), and lacustrine zones (Lz). The degradation of water quality was seasonally caused by resuspension of sediments, monsoon input due to rainfall inflow, and intensity of Asian monsoon, and was also related to intensive anthropic activities within the catchment. The empirical model and PCA showed that light availability was directly controlled by non-algal turbidity, which was a more important regulator of CHL-a than total nitrogen (TN) and total phosphorus (TP). The TSID supported our hypothesis on the non-algal turbidity. We also found that the construction of serial upper weirs influenced nutrient regime, TSS, CHL-a level, and trophic state in the estuarine reservoir, resulting in lower TP and TN but high CHL-a and high TN/TP ratios. The proportions of both dissolved color clay particles and blue-green algae in the TSID additionally increased. Overall, the long-term patterns of nutrients, suspended solids, and algal biomass changed due to seasonal runoff, turnover time, and reservoir zones along with anthropic impacts of the upper weir constructions, resulting in changes in trophic state variables and their mutual relations in the estuarine reservoir.

Turkish Muslims in a German city: Entrepreneurial and residential self-determination

2015 ◽  
Vol 12 (1) ◽  
pp. 1-12
Author(s):  
Sarah Hackett
Keyword(s):  
Residential Patterns ◽  
Academic Literature ◽  
Self Employment ◽  
German City ◽  
Post War ◽  
Oral History Interviews ◽  
The City ◽  
Insight Into ◽  
Term Objective

Drawing upon a collection of oral history interviews, this paper offers an insight into entrepreneurial and residential patterns and behaviour amongst Turkish Muslims in the German city of Bremen. The academic literature has traditionally argued that Turkish migrants in Germany have been pushed into self-employment, low-quality housing and segregated neighbourhoods as a result of discrimination, and poor employment and housing opportunities. Yet the interviews reveal the extent to which Bremen’s Turkish Muslims’ performances and experiences have overwhelmingly been the consequences of personal choices and ambitions. For many of the city’s Turkish Muslim entrepreneurs, self-employment had been a long-term objective, and they have succeeded in establishing and running their businesses in the manner they choose with regards to location and clientele, for example. Similarly, interviewees stressed the way in which they were able to shape their housing experiences by opting which districts of the city to live in and by purchasing property. On the whole, they perceive their entrepreneurial and residential practices as both consequences and mediums of success, integration and a loyalty to the city of Bremen. The findings are contextualised within the wider debate regarding the long-term legacy of Germany’s post-war guest-worker system and its position as a “country of immigration”.

Moving Songs

2019 ◽  
pp. 590-606
Author(s):  
Sally Treloyn ◽  
Matthew Dembal Martin ◽  
Rona Goonginda Charles
Keyword(s):  
Cultural Heritage ◽  
Knowledge Transmission ◽  
Intercultural Relationships ◽  
Cultural Negotiation ◽  
Intercultural Collaboration ◽  
Present Collection ◽  
Intergenerational Knowledge ◽  
Early Phases ◽  
Insight Into

Repatriation has become almost ubiquitous in ethnomusicological research on Australian Indigenous song. This article provides insights into processes of a repatriation-centered song revitalization project in the Kimberley, northwest Australia. Authored by an ethnomusicologist and two members of the Ngarinyin cultural heritage community, the article provides firsthand accounts of the early phases of a long-term repatriation-centered project referred to locally as the Junba Project. The authors provide a sample of narratives and dialogues that deliver insight into experiences of the work of identifying recordings “in the archive” and cultural negotiation and use of recordings “on Country.” The entanglement of local epistemological frameworks with past and present collection, archival research, repatriation, and dissemination for intergenerational knowledge transmission between spirits, Country, and the living, is explored, showing how recordings move song knowledge from community to archive to community and from generation to generation, and move people in present-day communities. The chapter considers how these “moving songs” allow an interrogation of the fraught endeavor of intercultural collaboration in the pursuit of revitalizing Indigenous song traditions. It positions repatriation as a method that can support intergenerational knowledge transmission and as a method to consider past and present intercultural relationships within research projects and between cultural heritage communities and collecting institutions.

scholarly journals Satellite-Derived Protein Concentration of Phytoplankton in the Southwestern East/Japan Sea

2021 ◽  
Vol 9 (2) ◽  
pp. 189
Author(s):  
Hyeonji Bae ◽  
Dabin Lee ◽  
Jae Joong Kang ◽  
Jae Hyung Lee ◽  
Naeun Jo ◽  
...  
Keyword(s):  
Protein Concentration ◽  
Japan Sea ◽  
Biological Properties ◽  
Measured Data ◽  
Trophic Levels ◽  
Coefficient Of Determination ◽  
P Value ◽  
Chl A ◽  
Major Factors

The cellular macromolecular contents and energy value of phytoplankton as primary food source determine the growth of higher trophic levels, affecting the balance and sustainability of oceanic food webs. Especially, proteins are more directly linked with basic functions of phytoplankton biosynthesis and cell division and transferred through the food chains. In recent years, the East/Japan Sea (EJS) has been changed dramatically in environmental conditions, such as physical and chemical characteristics, as well as biological properties. Therefore, developing an algorithm to estimate the protein concentration of phytoplankton and monitor their spatiotemporal variations on a broad scale would be invaluable. To derive the protein concentration of phytoplankton in EJS, the new regional algorithm was developed by using multiple linear regression analyses based on field-measured data which were obtained from 2012 to 2018 in the southwestern EJS. The major factors for the protein concentration were identified as chlorophyll-a (Chl-a) and sea surface nitrate (SSN) in the southwestern EJS. The coefficient of determination (r2) between field-measured and algorithm-derived protein concentrations was 0.55, which is rather low but reliable. The satellite-derived estimation generally follows the 1:1 line with the field-measured data, with Pearson’s correlation coefficient, which was 0.40 (p-value < 0.01, n = 135). No remarkable trend in the long-term annual protein concentration of phytoplankton was found in the study area during our observation period. However, some seasonal difference was observed in winter protein concentration between the 2003–2005 and 2017–2019 periods. The algorithm is developed for the regional East/Japan Sea (EJS) and could contribute to long-term monitoring for climate-associated ecosystem changes. For a better understanding of spatiotemporal variation in the protein concentration of phytoplankton in the EJS, this algorithm should be further improved with continuous field surveys.

scholarly journals Surface Water Temperature Predictions at a Mid-Latitude Reservoir under Long-Term Climate Change Impacts Using a Deep Neural Network Coupled with a Transfer Learning Approach

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1109
Author(s):  
Nobuaki Kimura ◽  
Kei Ishida ◽  
Daichi Baba
Keyword(s):  
Climate Change ◽  
Surface Water ◽  
Water Temperature ◽  
Transfer Learning ◽  
Air Temperature ◽  
Climate Models ◽  
Temporal Variations ◽  
Training Data ◽  
Surface Water Temperature

Long-term climate change may strongly affect the aquatic environment in mid-latitude water resources. In particular, it can be demonstrated that temporal variations in surface water temperature in a reservoir have strong responses to air temperature. We adopted deep neural networks (DNNs) to understand the long-term relationships between air temperature and surface water temperature, because DNNs can easily deal with nonlinear data, including uncertainties, that are obtained in complicated climate and aquatic systems. In general, DNNs cannot appropriately predict unexperienced data (i.e., out-of-range training data), such as future water temperature. To improve this limitation, our idea is to introduce a transfer learning (TL) approach. The observed data were used to train a DNN-based model. Continuous data (i.e., air temperature) ranging over 150 years to pre-training to climate change, which were obtained from climate models and include a downscaling model, were used to predict past and future surface water temperatures in the reservoir. The results showed that the DNN-based model with the TL approach was able to approximately predict based on the difference between past and future air temperatures. The model suggested that the occurrences in the highest water temperature increased, and the occurrences in the lowest water temperature decreased in the future predictions.

scholarly journals Hypocalcemic cardiomyopathy after parathyroidectomy in a patient with uremia: A case report and literature review

2020 ◽  
Vol 48 (7) ◽  
pp. 030006052094211
Author(s):  
Wei Zhang ◽  
Feng Xue ◽  
Quandong Bu ◽  
Xuemei Liu
Keyword(s):  
Heart Failure ◽  
Case Report ◽  
Secondary Hyperparathyroidism ◽  
Calcium Supplementation ◽  
Severe Heart Failure ◽  
Cardiac Complications ◽  
Refractory Heart Failure ◽  
First Case ◽  
Insight Into

Hypocalcemia is a rare, but reversible, cause of dilated cardiomyopathy. Although cardiomyopathy may cause severe heart failure, calcium supplementation can reverse heart failure. We report here a patient with uremia and secondary hyperparathyroidism, who was complicated by persistent hypocalcemia and refractory heart failure. The cardiac failure was refractory to treatment with digitalis and diuretics, but dramatically responded to calcium therapy and restoration of normocalcemia. As a result, the patient was eventually diagnosed with hypocalcemic cardiomyopathy. To the best of our knowledge, this is the first case of this disease to be reported in a patient with uremia. Findings from our case may help clinicians to better understand hypocalcemic cardiomyopathy. Our case might also provide new insight into long-term cardiac complications and prognoses of patients undergoing parathyroidectomy due to secondary hyperparathyroidism.

scholarly journals R Coronae Borealis Stars: Long-Term Photometric & Spectroscopic Studies

1998 ◽  
Vol 11 (1) ◽  
pp. 379-379
Author(s):  
P.L. Cottrell ◽  
L. Skuljan ◽  
P.M. Kilmartin ◽  
C. Gilmore ◽  
W.A. Lawson
Keyword(s):  
Radial Velocity ◽  
Spectroscopic Studies ◽  
Photometric Data ◽  
Decline Phase ◽  
Dust Clouds ◽  
Medium Resolution ◽  
Formation And Evolution ◽  
R Coronae Borealis Stars ◽  
Insight Into

For more than a decade we have been able to acquire and analyse a significant amount of photometric data of the highly variable R Coronae Borealis (RCB) stars. This has made been possible by a photometric service observing programme instigated at the Observatory. These photometric data have been combined with less extensive spectroscopic coverage, particularly of the decline phase of these stars. These have been supplemented by observations obtained at Mount Stromlo and Siding Spring Observatories for a radial velocity study. Significantly more spectroscopic observations are now being acquired with the development of a new medium resolution spectrograph at Mount John University Observatory. In this poster we will present recent photometric and spectroscopic results for a number of the RCB stars in our sample. This observational and analysis work can be used to provide further insight into the nature of these stars, their likely progeny and progenitors and the processes that are involved in the formation and evolution of the obscuring dust clouds which cause the decline phase.

scholarly journals Characteristics of Liparis loeselii (L.) Rich. populations in selected Natura 2000 areas in eastern Poland

2020 ◽  
Vol 55 (3) ◽  
pp. 151-162
Author(s):  
Danuta Urban ◽  
Joanna Sender ◽  
Ewelina Tokarz ◽  
Andrzej Różycki
Keyword(s):  
Natura 2000 ◽  
Total Carbon ◽  
Habitat Conditions ◽  
Total Carbon Content ◽  
Poor Fen ◽  
Calcareous Fen ◽  
Liparis Loeselii ◽  
The Individual ◽  
Insight Into

AbstractIn view of the sensitivity of Liparis loeselii to changes in habitat conditions, we carried out a study with the aim to monitor population numbers, identify the individual features of the Liparis loeselii population, analyse habitat conditions, identify threats and propose conservation measures to preserve the species. The investigations were conducted in seven unmanaged objects located in three Natura 2000 areas in eastern Poland. The results of this study provide a new insight into Liparis loeselii ecology. The analysed populations inhabited some habitat types: extremely poor fen, transitional mire, rich fen, calcareous fen, spring-fed fen. The content of nutrients was similar in all the habitats. A CCA analysis revealed that the total carbon content, pH, and redox potential of the substrate determine differences between the habitats analysed. Juvenile individuals represented a maximum of 12% of the analysed populations and were the least abundant group of these plants. The flowering was primarily influenced by hydrological conditions. Based on the long-term observations reported in this article, it can be assumed that the species stands a chance of surviving at the localities analysed, provided that the habitat conditions do not change dramatically.

scholarly journals Dark metabolism: a molecular insight into how the Antarctic sea‐ice diatom Fragilariopsis cylindrus survives long‐term darkness

2019 ◽  
Vol 223 (2) ◽  
pp. 675-691 ◽  
Author(s):  
Fraser Kennedy ◽  
Andrew Martin ◽  
John P. Bowman ◽  
Richard Wilson ◽  
Andrew McMinn
Keyword(s):  
Sea Ice ◽  
Antarctic Sea Ice ◽  
Fragilariopsis Cylindrus ◽  
Dark Metabolism ◽  
The Antarctic ◽  
Insight Into

Influence of Reservoir Transit on Riverine Algal Transport and Abundance

1984 ◽  
Vol 41 (12) ◽  
pp. 1803-1813 ◽  
Author(s):  
D. M. Søballe ◽  
R. W. Bachmann
Keyword(s):  
Water Temperature ◽  
Retention Time ◽  
Standing Crop ◽  
Algal Biomass ◽  
Chlorophyll Concentration ◽  
Light Limitation ◽  
Des Moines ◽  
Flow Dependence ◽  
Major Loss ◽  
Chlorophyll Concentrations

The Des Moines River lost 65–75% of its algal standing crop (chlorophyll a) in passing through each of two impoundments (mean retention times 11 and 16 d), and chlorophyll concentrations within both impoundments were 50–90% below the predictions of empirical chlorophyll–nutrient models. Sedimentation of river-borne algae and light limitation within the impoundments were identified as major loss processes. A reduction in algal size from upstream to downstream in one reservoir paralleled the loss of algal biomass. Algal losses in each impoundment increased with both increasing retention time and water temperature so that chlorophyll concentration below the dams was uncoupled from the temperature and flow dependence seen in river reaches not influenced by impoundments. The reduction in riverine algal transport associated with reservoir transit was cumulative over the two-reservoir series; this reduction can be interpreted as a "reset" to river headwater conditions.

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