Short-term measurement of N2O emissions from sheep-grazed pasture receiving increasing rates of fertiliser nitrogen in Otago, New Zealand

2010 ◽  
Vol 50 (1) ◽  
pp. 17 ◽  
Author(s):  
S. A. Letica ◽  
C. A. M. de Klein ◽  
C. J. Hoogendoorn ◽  
R. W. Tillman ◽  
R. P. Littlejohn ◽  
...  
Keyword(s):  
Early Spring ◽  
Late Winter ◽  
N2o Emissions ◽  
Short Term ◽  
Hill Country ◽  
Best Management ◽  
Spring Period ◽  
Grazed Pasture ◽  
Application Rates ◽  
Short Term Study

The purpose of this short-term study was to investigate the effect of increasing fertiliser nitrogen (N) application rates on nitrous oxide (N2O) emissions over the late winter/early spring period from sheep-grazed pasture in Otago rolling hill country. We measured N2O gas emissions from plots on a mottled Fragic Pallic hill soil receiving 0, 100 and 500 kg N/ha.year for 2 years. Plots were sampled weekly for 10 weeks over the 2006 winter/spring period using a static chamber method. Increased N fertiliser rate and the attendant increase in stocking rate significantly increased total N2O emissions (P < 0.05). Total N2O emissions for the measurement period were estimated to be 0.08, 0.13 and 1.36 kg N2O-N/ha (s.e.m, 0.1, 0.18 and 0.45) for the 0, 100 and 500 N treatments, respectively. Our results suggest that high application rates of fertiliser N (i.e. 500 kg N/ha.year) and attendant increased stocking rates may significantly increase emissions of N2O even in dry winter/spring conditions in Otago rolling hill country. These results will assist in the development of best management guidelines for reducing N2O emissions from fertiliser N in hill country.

Cyclical Changes in the Distribution of the Testis Lipids of a Teleost Fish, Esox lucius

1957 ◽  
Vol s3-98 (41) ◽  
pp. 79-88
Author(s):  
B. LOFTS ◽  
A. J. MARSHALL
Keyword(s):  
Maximum Size ◽  
Early Spring ◽  
Day Length ◽  
Endocrine Function ◽  
Late Winter ◽  
Length Of Day ◽  
Spring Period ◽  
Sequence Of Events ◽  
Rhythmical Activity ◽  
Gradual Disappearance

A study of the cyclical changes in the distribution of testis lipids in the pike reveals a sequence of events comparable with that occurring in seasonal birds. These events include the post-nuptial appearance of cholesterol-positive lipid material which accumulates within the seminiferous lobules, and its subsequent gradual disappearance. A lipid cycle occurs also in the lobule walls, where apparently fibroblasts, in the absence of a true secretory interstitium, become glandular and probably take on an endocrine function. These ‘lobule boundary cells’ seasonally accumulate cholesterol-positive cytoplasmic lipids which suddenly become depleted at the time of the annual pre-spawning assembly. The pike differs from wild birds in the ‘timing’ of such rhythmical activity. In birds, despite a rapid post-nuptial interstitial regeneration, the tubule cholesterol lingers until spermatogenesis begins during the following late winter or spring. In the poikilothermous pike, on the other hand, the next spermatogenesis begins almost immediately (in June, when the temperature of the water is still rising). It continues without interruption while the length of day and later the temperature decrease, until the testis reaches its maximum size in December. ‘Lobule boundary cells’ start to become lipoidal in September, at a time of high temperature but decreasing day-length. The cells are fully charged by December. Both tubules and gland-cells now become inactive. Then in April at the spring period of increasing day-length, and immediately a iter water temperature starts to rise, the boundary cells begin to secrete and the prespawning assembly occurs. This is followed by the shedding of spermatozoa later in the month or early in May. The only period of true inactivity is at the height of spermatogenesis during mid-winter and early spring.

scholarly journals Variable and differential application of nutrients to a hill country farm

2017 ◽  
Vol 79 ◽  
pp. 119-123
Author(s):  
Jd Morton ◽  
A. Gillingham
Keyword(s):  
Financial Analysis ◽  
Economic Benefits ◽  
Early Spring ◽  
Late Winter ◽  
Variable Rate ◽  
Hill Country ◽  
Uniform Rate ◽  
The Cost ◽  
The Hill

Abstract Traditionally fertiliser has been aerially applied at a uniform rate to hill country, but the technology now exists to apply nutrients at a variable rate (VR) and each nutrient differentially, depending on the production potential and pasture composition of each part of the hill. A hypothetical case study of a sheep farm was modelled to show the economic benefits of VR application of phosphorus (P) and sulphur (S) and differential application of nitrogen (N), compared with application of a uniform rate of P and S. The financial analysis demonstrates that the VR strategy of less P and S to steeper slopes where there is low legume and more on easier slopes where there is more legume, costs less than the application of P and S at a uniform rate over all slopes. The cost saving could be used to apply N to steep land on both sunny and shady aspects and easy land on sunny aspects. This differential N application in late winter/early spring ensures better pasture cover for lactating ewes to improve ewe condition at weaning. When this gain in condition was maintained through to mating, lambing percentage increased in the following spring. The benefit from this increased lamb production was an increase in financial returns of $63/ha/year. A qualitative sensitivity analysis indicated that this value remains stable in response to changes in the proportion of each slope class, soil Olsen P level, the relative cost of fertiliser P and N and sheep to cattle ratio. Keywords: differential application, hill country, lamb production, nitrogen, phosphorus, aerial topdressing, variable rate

scholarly journals Influence of Short-term Cyclic Cold Temperature Stress on Muskmelon and Honeydew Yield

2003 ◽  
Vol 13 (1) ◽  
pp. 67-70
Author(s):  
Ahmet Korkmaz ◽  
Robert J. Dufault
Keyword(s):  
Cold Stress ◽  
Temperature Stress ◽  
Cucumis Melo ◽  
Early Spring ◽  
Cold Temperature ◽  
Yield Reduction ◽  
Late Winter ◽  
Short Term ◽  
Early Planting

Muskmelon (Cucumis melo) seedlings are transplanted in late winter or early spring before last frost date to ensure early yields; however, this makes them very vulnerable to temperatures cycling between almost freezing and optimal temperatures. To simulate temperature alternations that may occur after field transplanting, `Athena', `Sugar Bowl', `Eclipse' muskmelon, and `Tesorro Dulce' honeydew (C. melo) transplants were subjected to 2 ± 1 °C (35.6 ± 1.8 °F) in a walk-in cooler and then to 29 ± 5 °C (84.2 ± 9.0 °F) in a greenhouse before field planting. In 1998, transplants were exposed to 2 °C for 9 to 54 hours, and for 9 to 81 hours in 1999. `Athena' and `Sugar Bowl' yielded less early melons in both years, whereas `Eclipse' and `Tesoro Dulce' early yields were only reduced in 1999. Total yields of `Athena' decreased linearly in both years with 10% yield reduction occurring with 12 to 21 hours of cold stress. Total yields of `Sugar Bowl' decreased linearly in both years with 11 to 18 hours of cold stress causing 10% yield reduction in 1998 and 1999, respectively. Therefore, early planting before last frosts of all these muskmelon and honeydew cultivars should be done with caution since reductions in early yields are highly probable.

scholarly journals The long-term use of nitrogen fertiliser in intensive hill country farming

1993 ◽  
pp. 59-61
Author(s):  
D. Daniell
Keyword(s):  
Animal Health ◽  
Nitrogen Compound ◽  
Land Development ◽  
Cost Effective ◽  
Early Spring ◽  
Diammonium Phosphate ◽  
Late Winter ◽  
Hill Country ◽  
Supplementary Feed ◽  
Initial Objective

In 1969 the initial objective in using a nitrogen compound fertiliser was to bridge a feed deficit in late winter-early spring. Further advantages were observed, including an improvement in pastures from browntop to ryegrass dominance, better growth into dry summer, and faster recovery from droughts. Diammonium phosphate (DAP) was also incorporated into land development out of manuka, resulting in much faster establishment of dense pasture. Cost comparisons with superphosphate encouraged the use of DAP as an annual maintenance fertiliser from 1975, usually at a rate of 125 kg/ha. Details are given of sulphur additives, molybdenum, lime and copper for animal health. The lift in productivity from 1969 to 1992 is shown. The conclusion is that a DAP/ sulphur fertiliser applied from late autumn to early spring is a cost-effective and balanced input. It allows a high stocking rate (12/ha) on poorer hill country, without supplementary feed, plus high per head performance. Feed generated has been sufficient to shear 2100 ram hoggets in early August, culminating in ram sales of 1400 per year. Lambing percentages are above 130% survival to sale in good years, and wool weights have averaged 7.7 kg/year, including wool sold on sheeps' back. Ewe hoggets are mated, averaging 30% survival to sale. Keywords: diammonium phosphate, feed cover, fertiliser, hill country, land development

Cultural Awareness of Students in Communication Sciences and Disorders: A Mixed-Methods Study

2020 ◽  
Vol 5 (5) ◽  
pp. 1231-1242
Author(s):  
Celeste Domsch ◽  
Lori Stiritz ◽  
Jay Huff
Keyword(s):  
United States ◽  
Study Abroad ◽  
Cultural Awareness ◽  
Qualitative Data ◽  
The United States ◽  
Self Report ◽  
Global Awareness ◽  
Short Term ◽  
Term Study ◽  
Short Term Study

Purpose This study used a mixed-methods design to assess changes in students' cultural awareness during and following a short-term study abroad. Method Thirty-six undergraduate and graduate students participated in a 2-week study abroad to England during the summers of 2016 and 2017. Quantitative data were collected using standardized self-report measures administered prior to departure and after returning to the United States and were analyzed using paired-samples t tests. Qualitative data were collected in the form of daily journal reflections during the trip and interviews after returning to the United States and analyzed using phenomenological methods. Results No statistically significant changes were evident on any standardized self-report measures once corrections for multiple t tests were applied. In addition, a ceiling effect was found on one measure. On the qualitative measures, themes from student transcripts included increased global awareness and a sense of personal growth. Conclusions Measuring cultural awareness poses many challenges. One is that social desirability bias may influence responses. A second is that current measures of cultural competence may exhibit ceiling or floor effects. Analysis of qualitative data may be more useful in examining effects of participation in a short-term study abroad, which appears to result in decreased ethnocentrism and increased global awareness in communication sciences and disorders students. Future work may wish to consider the long-term effects of participation in a study abroad for emerging professionals in the field.

Community Involvement and Benefits From an International Service Learning Program

2017 ◽  
Vol 2 (7) ◽  
pp. 5-12 ◽  
Author(s):  
Lata A. Krishnan ◽  
Christi Masters ◽  
Jennifer M. Simpson
Keyword(s):  
Service Learning ◽  
Experiential Learning ◽  
Community Involvement ◽  
Learning Program ◽  
Short Term ◽  
International Service Learning ◽  
International Service ◽  
Short Term Study ◽  
Service Activities ◽  
Study Abroad Program

Service learning (SL) is a form of experiential learning in which students are involved in community service activities that are related to academic course objectives. A key aspect that separates SL from other forms of experiential learning is the mutually beneficial nature of the service activities. Much of the SL and international SL (ISL) literature has focused on positive learning outcomes for students, with much less focus on the benefits of SL to the community. Speech, Language, and Hearing Services (SLHS) in Zambia is an intensive SL short-term study abroad program. This paper describes the benefits to the community via the SLHS in Zambia program.

1696: May Phyllanthus Niruri ( Uriston®) Affect the Efficacy of ESWL on Renal Stones? A Prospective, Randomised Short Term Study

2005 ◽  
Vol 173 (4S) ◽  
pp. 460-460
Author(s):  
Antonio Celia ◽  
Salvatore Micali ◽  
Sighinolfi Maria Chiara ◽  
Grande Marco ◽  
Di Pietro Corradino ◽  
...  
Keyword(s):  
Renal Stones ◽  
Short Term ◽  
Phyllanthus Niruri ◽  
Term Study ◽  
Short Term Study

Emplacing Berlin: Digital Itineraries and Short-term Study Abroad in the City

2018 ◽  
Vol 12 (1) ◽  
pp. 26-36 ◽  
Author(s):  
Richard B. Apgar
Keyword(s):  
Study Abroad ◽  
Urban Landscape ◽  
Physical Space ◽  
Short Term ◽  
Study Abroad Programs ◽  
Term Study ◽  
Digital Maps ◽  
Short Term Study ◽  
The City

As destination of choice for many short-term study abroad programs, Berlin offers students of German language, culture and history a number of sites richly layered with significance. The complexities of these sites and the competing narratives that surround them are difficult for students to grasp in a condensed period of time. Using approaches from the spatial humanities, this article offers a case study for enhancing student learning through the creation of digital maps and itineraries in a campus-based course for subsequent use during a three-week program in Berlin. In particular, the concept of deep mapping is discussed as a means of augmenting understanding of the city and its history from a narrative across time to a narrative across the physical space of the city. As itineraries, these course-based projects were replicated on site. In moving from the digital environment to the urban landscape, this article concludes by noting meanings uncovered and narratives formed as we moved through the physical space of the city.

The role of immersion learning in the acquisition and processing of L2 gender agreement

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Gabrielle Klassen ◽  
Aline Ferreira ◽  
John W. Schwieter
Keyword(s):  
Second Language ◽  
Second Language Acquisition ◽  
Study Abroad ◽  
Morphological Variability ◽  
Selection Task ◽  
Gender Agreement ◽  
Short Term ◽  
Term Study ◽  
Reading Task ◽  
Short Term Study

Abstract In this paper, we examine the effects of learning environment on second language (L2) gender agreement. English speakers learning L2 Spanish participated in a self-paced reading task and a picture selection task prior to and after a short-term study abroad experience. The results from the self-paced reading task showed that their reliance on the masculine article as the default (e.g., McCarthy, Corrine. 2008. Morphological variability in the comprehension of agreement: An argument for representation over computation. Second Language Research 24(4). 459–486) was reduced over time abroad. Findings from the picture selection task showed that the learners did not attend to the gender of articles unless it was their only cue, but that after the study abroad experience they began to use gender as an anticipatory cue for lexical selection. We interpret these results as support for an adapted version of the Shallow Structures Hypothesis (Clahsen, Harald & Claudia Felser. 2006a. Grammatical processing in language learners. Applied Psycholinguistics 27(1). 3–42; Clahsen, Harald & Claudia Felser. 2006b. How native-like is non-native language processing? Trends in Cognitive Sciences 10(12). 564–570) and the notion that in immersion contexts L2 learners shift their parsing strategy to be more communicatively focused (Schwieter, John W. & Gabrielle Klassen. 2016. Linguistic advances and learning strategies in a short-term study abroad experience. Study Abroad Research in Second Language Acquisition and International Education 1(2). 217–247).

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