Seasonal variation in phosphorus removal processes _within reed beds - mass balance investigations

2003 ◽  
Vol 48 (5) ◽  
pp. 59-66 ◽  
Author(s):  
T.R. Headley ◽  
D.O. Huett ◽  
L. Davison
Keyword(s):  
Mass Balance ◽  
Loading Rate ◽  
First Year ◽  
Dominant Form ◽  
Reed Beds ◽  
Ground Biomass ◽  
Below Ground ◽  
Removal Processes ◽  
Second Year ◽  
P Removal

The phosphorus (P) removal processes in two pairs of High and Low Loaded reed beds were investigated during five periods within a 27-month study. The uptake/release of P was measured in seven mass balance compartments. With the exception of the first year of operation, the reed beds consistently removed over 96% of the influent P load, with total phosphorus (TP) concentrations being reduced from 0.5 mg/L to generally less than 0.005 mg/L across the range of loading rates and seasons studied. During the first year, uptake by Phragmites australis accounted for greater than 75% of P removed, and was equally distributed between above and below-ground biomass. During the second and third years, three seasonal stages were identified in the uptake and cycling of P by P. australis. A period of rapid above-ground growth and uptake occurred during spring fuelled partly by P reserves accumulated in rhizomes during the previous year. During summer, uptake by above-ground biomass was governed by the influent P loading rate, while the amount of P held in below-ground biomass remained relatively stable. During autumn and winter, P appeared to be translocated from senescent shoots to reserves in the rhizomes. Approximately 85% of the below-ground biomass P occurred in the top 20 cm of the substrate. Gravel fixation increased in importance from 12% in the first year to approximately 30% of P removed in the second year, with a highly significant correlation between the influent P loading rate and P fixed by the gravel. The weakly-bound P fraction from a sequential extraction was the dominant form of P fixed by the gravel. HCl extracts were inappropriate for the examination of sorption processes as they dissolved large amounts of mineral P from within the basaltic gravel. The bottom 30 cm of the substrate became the most important site for gravel fixation during the second year. Incorporation of P into the detritus/microbiota/other compartment increased after the first year to become one of the most important P removal processes, probably consisting mainly of leaf litter and slowly accreted organic sediments.

scholarly journals Snow contribution to first-year and second-year Arctic sea ice mass balance north of Svalbard

2017 ◽  
Vol 122 (3) ◽  
pp. 2539-2549 ◽  
Author(s):  
Mats A. Granskog ◽  
Anja Rösel ◽  
Paul A. Dodd ◽  
Dmitry Divine ◽  
Sebastian Gerland ◽  
...  
Keyword(s):  
Sea Ice ◽  
Mass Balance ◽  
Arctic Sea Ice ◽  
First Year ◽  
Arctic Sea ◽  
Ice Mass Balance ◽  
Second Year

An inevitable crisis? From first to second year in counsellor training

2020 ◽  
Vol 5 (1) ◽  
pp. 74-89
Author(s):  
Hugh Crago
Keyword(s):  
Right Hemisphere ◽  
Training Programme ◽  
First Year ◽  
Training Experience ◽  
Counsellor Training ◽  
Student Dropout ◽  
Second Year ◽  
Neurological Research ◽  
First Year Of Life ◽  
And Control

In a seminal 1973 paper, Robert Clark described the very different “cultures” of the first and second year students in a four year clinical psychology PhD programme. The author applies Clark’s template to his own experiences as trainee or trainer in five different counsellor education programmes, one in the US and four in Australia. Each of the programmes, to varying degrees, demonstrates key features of the pattern identified by Clark, where the first year is “therapeutic” and other-oriented, the second is “professional” and self-focused. The author concludes that all the surveyed programmes exhibited some level of “second year crisis”, in which a significant number of students felt abandoned, dissatisfied, or rebellious. The author extends and refines Clark’s developmental analogy (first year = childhood; second year = adolescence) to reflect recent neurological research, in particular, the shift from a right hemisphere-dominant first year of life, prioritising affiliative needs, to a left hemisphere-dominant second year, prioritising autonomy and control. This shift is paralleled later by a more gradual move from a protective, supportive childhood to necessary, but sometimes conflictual, individuation in adolescence. The first two years of a counsellor training programme broadly echo this process, a process exacerbated by the second year internship/placement, in which students must “leave home” and adjust to unfamiliar, potentially less nurturing, authority figures. Finally, the author suggests introducing more rigorous “academic holding” into the first year, and greater attention to “therapeutic holding” of dissident students in the second, hopefully decreasing student dropout, and achieving a better balanced training experience.

Implementation of the Second-year course in an Engineering Professional Spine

2018 ◽  
Author(s):  
Umar Iqbal ◽  
Deena Salem ◽  
David Strong
Keyword(s):  
Learning Outcomes ◽  
Research University ◽  
Engineering Students ◽  
Employability Skills ◽  
First Year ◽  
Computer Engineering ◽  
Core Courses ◽  
Second Year ◽  
First Time ◽  
Academic Year

The objective of this paper is to document the experience of developing and implementing a second-year course in an engineering professional spine that was developed in a first-tier research university and relies on project-based core courses. The main objective of this spine is to develop the students’ cognitive and employability skills that will allow them to stand out from the crowd of other engineering graduates.The spine was developed and delivered for the first time in the academic year 2010-2011 for first-year general engineering students. In the year 2011-2012, those students joined different programs, and accordingly the second-year course was tailored to align with the different programs’ learning outcomes. This paper discusses the development and implementation of the course in the Electrical and Computer Engineering (ECE) department.

Exploring the Implementation of Early Math Assessments in Kindergarten Classrooms: A Research-Practice Collaboration

2020 ◽  
Author(s):  
Jennifer McDonald ◽  
Rebecca Merkley ◽  
Jacqueline Mickle ◽  
Lisa Collimore ◽  
Daniel Ansari
Keyword(s):  
Mathematical Thinking ◽  
Math Education ◽  
Kindergarten Students ◽  
First Year ◽  
Research Practice ◽  
Early Numeracy ◽  
Future Directions ◽  
Collaborative Project ◽  
Practice Gap ◽  
Second Year

Research in cognitive development has highlighted that early numeracy skills are associated with later math achievement, suggesting that these skills should be targeted in early math education. Here we tested whether tools used by researchers to assess mathematical thinking could be useful in the classroom. This paper describes a collaborative project between cognitive scientists and school board researchers/educators implementing numeracy screeners with kindergarten students over the course of three school years. The Give-A-Number task (Wynn, 1990) was used with first-year kindergarten students and the Numeracy Screener [BLINDED] with second-year kindergarten students. Results indicated that educators (N = 59) found the tools feasible to implement and helpful for exploring their students’ thinking and targeting instruction. The Educators’ feedback also helped inform improvements to the implementation of the tools and future directions for both the schools and the researchers. This work emphasizes the importance of transdisciplinary collaboration to address the research-practice gap.

Influence of abiotic factors and hosts on seasonal dynamic of green lacewing, Chrysoperla carnea (Stephens)

2016 ◽  
Vol 3 (3) ◽  
Author(s):  
ARVIND KUMAR ◽  
POOJA KHULBE
Keyword(s):  
Abiotic Factors ◽  
Host Population ◽  
Maximum Temperature ◽  
First Year ◽  
Green Lacewing ◽  
Larval Population ◽  
Correlation Studies ◽  
Helianthus Annus ◽  
Sunflower Crop ◽  
Second Year

Influence of abiotic factors and hosts on population dynamics of green lacewing, Chrysoper lacarnea (Stephens) was studied in sunflower, Helianthus annus (Linn.).The maximum number of C. carnea population was found during mid March –mid April in the first year and mid April – mid May in the second year in sunflower crop. The maximum number of host population viz. egg and larva of Helicoverpa armigera and Myzuspe rsicae population were found during mid March –mid April in both the year and correlation studies revealed the positive and significant correlation between larval population of H. armigera, M. persicae and predator C. carnea. While there was no significant relationship found between eggs of H. armigera and C. carnea. The C. carnea population on H. annus during both the year was positively correlated with maximum temperature and found significant,while negatively correlated with relative humidity.However, no significant correlation of C. carnea was found with minimum temperature in both the year.

Effects of Cutting First Year Red Clover on Stand and Yield in the Second Year 1

1955 ◽  
Vol 47 (5) ◽  
pp. 224-228 ◽  
Author(s):  
James H. Torrie ◽  
Earle W. Hanson
Keyword(s):  
Red Clover ◽  
First Year ◽  
Second Year

scholarly journals Socio-economic consequences of mental distress: quantifying the impact of self-reported mental distress on the days of incapacity to work and medical costs in a two-year period: a longitudinal study in Germany

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Gerhard Müller ◽  
Manuela Bombana ◽  
Monika Heinzel-Gutenbrenner ◽  
Nikolaus Kleindienst ◽  
Martin Bohus ◽  
...  
Keyword(s):  
Mental Disorders ◽  
Mental Distress ◽  
Linear Models ◽  
Longitudinal Research ◽  
Depression Scale ◽  
Routine Data ◽  
Medical Costs ◽  
First Year ◽  
Second Year ◽  
The Impact

Abstract Background Mental disorders are related to high individual suffering and significant socio-economic burdens. However, it remains unclear to what extent self-reported mental distress is related to individuals’ days of incapacity to work and their medical costs. This study aims to investigate the impact of self-reported mental distress for specific and non-specific days of incapacity to work and specific and non-specific medical costs over a two-year span. Method Within a longitudinal research design, 2287 study participants’ mental distress was assessed using the Hospital Anxiety and Depression Scale (HADS). HADS scores were included as predictors in generalized linear models with a Tweedie distribution with log link function to predict participants’ days of incapacity to work and medical costs retrieved from their health insurance routine data during the following two-year period. Results Current mental distress was found to be significantly related to the number of specific days absent from work and medical costs. Compared to participants classified as no cases by the HADS (2.6 days), severe case participants showed 27.3-times as many specific days of incapacity to work in the first year (72 days) and 10.3-times as many days in the second year (44 days), and resulted in 11.4-times more medical costs in the first year (2272 EUR) and 6.2-times more in the second year (1319 EUR). The relationship of mental distress to non-specific days of incapacity to work and non-specific medical costs was also significant, but mainly driven from specific absent days and specific medical costs. Our results also indicate that the prevalence of presenteeism is considerably high: 42% of individuals continued to go to work despite severe mental distress. Conclusions Our results show that self-reported mental distress, assessed by the HADS, is highly related to the days of incapacity to work and medical costs in the two-year period. Reducing mental distress by improving preventive structures for at-risk populations and increasing access to evidence-based treatments for individuals with mental disorders might, therefore, pay for itself and could help to reduce public costs.

scholarly journals Field Efficacy of Steinernema sp. (Rhabditida: Steinernematidae) on the Colorado Potato Beetle Overwintering Generation

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1464
Author(s):  
Maja Čačija ◽  
Renata Bažok ◽  
Majda Kolenc ◽  
Tena Bujas ◽  
Zrinka Drmić ◽  
...  
Keyword(s):  
Colorado Potato Beetle ◽  
First Generation ◽  
Control Measures ◽  
Recommended Dose ◽  
Steinernema Feltiae ◽  
First Year ◽  
Potato Beetle ◽  
Field Efficacy ◽  
Second Year ◽  
Economic Pest

Colorado potato beetle (CPB) is an economic pest of potato that has developed resistance to all classes of chemical insecticides, thus requiring alternative control measures. As a potential solution, entomopathogenic nematodes (EPNs) have proven effective in suppressing this pest, but their efficacy against overwintering generations of CPB in Croatia has not been sufficiently researched. The aim of this two-year (2018–2019) field study was to determine the efficacy of Steinernema feltiae and Steinernema carpocapsae applied to overwintering CPB adults. EPNs were applied at three doses (7.5 mil./10 m2, 5.0 mil./10 m2 (the recommended dose) and 2.5 mil./10 m2) by watering the soil where the adults were overwintering. The first-year results were satisfactory for both EPNs: the efficacy of S. feltiae ranged from 79.03% to 100.00%, while the efficacy of S. carpocapsae ranged from 77.32% to 96.22%. In the second year, the highest efficacy (69.57%) was obtained using the recommended dose of S. feltiae. Although the results are not consistent across the two years of our study and suggest further research, they indicate that EPNs have great potential in controlling overwintering CPB generations to reduce first generation abundance and damage, and also to prevent the spread of new generations to surrounding potato growing areas.

scholarly journals Sperm Cryopreservation in American Flamingo (Phoenicopterus Ruber): Influence of Cryoprotectants and Seminal Plasma Removal

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 203
Author(s):  
María Gemma Millán de la Blanca ◽  
Eva Martínez-Nevado ◽  
Cristina Castaño ◽  
Juncal García ◽  
Berenice Bernal ◽  
...  
Keyword(s):  
Seminal Plasma ◽  
Genetic Material ◽  
First Year ◽  
Sperm Cryopreservation ◽  
Straight Line ◽  
The Family ◽  
Second Year ◽  
American Flamingo ◽  
Phoenicopterus Ruber

The American flamingo is a useful model for the development of successful semen cryopreservation procedures to be applied to threatened related species from the family Phoenicopteridae, and to permit genetic material banking. Current study sought to develop effective sperm cryopreservation protocols through examining the influences of two permeating cryoprotectants and the seminal plasma removal. During two consecutive years (April), semen samples were collected and frozen from American flamingos. In the first year, the effect of two permeating cryoprotectants, DMA (dimethylacetamide) (6%) or Me2SO (dimethylsulphoxide) (8%), on frozen–thawed sperm variables were compared in 21 males. No differences were seen between DMA and Me2SO for sperm motility, sperm viability, and DNA fragmentation after thawing. In the second year, the role of seminal plasma on sperm cryoresistance was investigated in 31 flamingos. Sperm samples were cryopreserved with and without seminal plasma, using Me2SO (8%) as a cryoprotectant. The results showed that samples with seminal plasma had higher values than samples without seminal plasma for the following sperm variables: Straight line velocity (22.40 µm/s vs. 16.64 µm/s), wobble (75.83% vs. 69.40%), (p < 0.05), linearity (62.73% vs. 52.01%) and straightness (82.38% vs. 73.79%) (p < 0.01); but acrosome integrity was lower (55.56% vs. 66.88%) (p < 0.05). The cryoresistance ratio (CR) was greater in samples frozen with seminal plasma than without seminal plasma for CR-progressive motility (138.72 vs. 54.59), CR-curvilinear velocity (105.98 vs. 89.32), CR-straight line velocity (152.77 vs. 112.58), CR-average path velocity (122.48 vs. 98.12), CR-wobble (111.75 vs. 102.04) (p < 0.05), CR-linearity (139.41 vs. 113.18), and CR-straightness (124.02 vs. 109.97) (p < 0.01). This research demonstrated that there were not differences between Me2SO and DMA to successful freezing sperm of flamingos; seminal plasma removal did not provide a benefit for sperm cryopreservation.

scholarly journals Effect of thinning intensity on understory herbaceous diversity and biomass in mixed coniferous and broad-leaved forests of Changbai Mountain

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Gerong Wang ◽  
Yue Sun ◽  
Mo Zhou ◽  
Naiqian Guan ◽  
Yuwen Wang ◽  
...  
Keyword(s):  
Seasonal Changes ◽  
Mixed Forest ◽  
Growing Season ◽  
Total Biomass ◽  
Herb Layer ◽  
Simpson Index ◽  
Thinning Intensity ◽  
Ground Biomass ◽  
Below Ground ◽  
Understory Herb

Abstract Background Herbs are an important part of the forest ecosystem, and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances. Based on the near-mature secondary coniferous and broad-leaved mixed forest in Jilin Province Forestry Experimental Zone, this study analyzed seasonal changes of species diversity and biomass of the understory herb layer after different intensities of thinning. Results The results showed that although the composition of herbaceous species and the ranking of importance values were affected by thinning intensity, they were mainly determined by seasonal changes. Across the entire growing season, the species with the highest importance values in thinning treatments included Carex pilosa, Aegopodium alpestre, Meehania urticifolia, and Filipendula palmata, which dominated the herb layer of the coniferous and broad-leaved mixed forest. The number of species, Margalef index, Shannon-Wiener index and Simpson index all had their highest values in May, and gradually decreased with months. Pielou index was roughly inverted “N” throughout the growing season. Thinning did not increase the species diversity. Thinning can promote the total biomass, above- and below-ground biomass. The number of plants per unit area and coverage were related to the total biomass, above- and below-ground biomass. The average height had a significantly positive correlation with herb biomass in May but not in July. However, it exerted a significantly negative correlation with herb biomass in September. The biomass in the same month increased with increasing thinning intensity. Total herb biomass, above- and below-ground biomass showed positive correlations with Shannon-Winner index, Simpson index and Pielou evenness index in May. Conclusions Thinning mainly changed the light environment in the forest, which would improve the plant diversity and biomass of herb layer in a short time. And different thinning intensity had different effects on the diversity of understory herb layer. The findings provide theoretical basis and reference for reasonable thinning and tending in coniferous and broad-leaved mixed forests.

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