scholarly journals REDUCTION IN GROWTH OF WHITE SPRUCE AFTER OUT-PLANTING

1964 ◽  
Vol 40 (4) ◽  
pp. 488-502 ◽  
Author(s):  
R. E. Mullin
Keyword(s):  
Growing Season ◽  
White Spruce ◽  
First Year ◽  
Age Classes ◽  
Nursery Stock ◽  
Before And After

Several age-classes of nursery stock were sampled before and after the 1963 growing season by excavation of trees. Samples were also planted out and later excavated. Studies of several criteria to express check were made and leader length selected as the most practicable.It is suggested that, by definition, a tree be considered in check until it has achieved a rate of terminal growth equivalent to that it would have attained in the next season in the nursery. Average leader lengths of unchecked trees are suggested for 2-0, 3-0 and 2-2 stock. Check was found to reduce leader length by about 50% in the first year after outplanting. Other experiments indicate that the effect continued for ten years or more in many instances.

Effect of length of growing season on development of hard seeds in yellow serradella and their subsequent softening at various depths of burial

1999 ◽  
Vol 50 (7) ◽  
pp. 1211 ◽  
Author(s):  
C. K. Revell ◽  
G. B. Taylor ◽  
P. S. Cocks
Keyword(s):  
Soil Surface ◽  
Growing Season ◽  
First Year ◽  
Variable Effect ◽  
Softening Mechanism ◽  
Hard Seeds ◽  
Before And After ◽  
Viable Seeds ◽  
A Site ◽  
Seed Yields

Effects of withholding water at 4 (W4) and 8 (W8) weeks after commencement of flowering on seed development in 2 accessions of yellow serradella (Ornithopus compressus L.), cv. Avila and accession GEH72-1A, were investigated in swards at a site near Perth, Western Australia. Softening of resulting hard seeds during the following summer and autumn was then studied in newly ripened pods placed at the soil surface, and at depths of 0.5 and 2 cm in the soil at Merredin in the first week of January. Proportions of soft seeds were determined in the original seed populations and in pods taken from the field in March and June. In 2 further treatments, proportions of soft seeds were determined in June in (i) pods that had been at the soil surface until they were buried at 2 cm in March, and (ii) in pods that had been buried at 2 cm until March, when they were returned to the soil surface. Seed yields from W4 were about 35% of those from W8 owing to reductions in pod numbers (partly as a result of more flower shedding in W4), number of seeds per pod, and seed size. Developing seeds became germinable between 21 and 29 days after anthesis when seed dry weights were between 0.9 and 1.4 mg, which was about the same time that they developed the capacity for seed coat impermeability. Viability of hard seeds was almost 100% from W8 but only 65% from the W4 treatments. Less than 5% of the newly ripened viable seeds were soft in any of the treatments. Length of growing season had no effect on seed softening at the soil surface and only a relatively small and variable effect on softening in buried pods. At the June sampling, up to 16% of Avila and 5% of GEH72-1A seeds had softened at the soil surface. Burial of pods increased proportions of soft seeds up to 85% in Avila and 53% in GEH72-1A. Whereas most of the seed softening in Avila occurred before March, similar amounts of softening occurred before and after the March sampling in GEH72-1A. Burial of pods in March increased seed softening by June in GEH72-1A but reduced softening in Avila, whereas transfer of buried pods to the soil surface in March had the reverse effect. This seed softening behaviour is explained in terms of the 2-stage seed softening mechanism. Burial of newly ripened seeds by tillage or stock trampling during the first summerŒautumn appears a feasible management option for improving first year regeneration in at least the softer seeded accessions of yellow serradella.

scholarly journals SURVIVAL AND GROWTH OF WHITE SPRUCE WILDLINGS AND COASTAL NURSERY SEEDLINGS IN THE INTERIOR OF BRITISH COLUMBIA

1966 ◽  
Vol 42 (4) ◽  
pp. 346-349 ◽  
Author(s):  
S. Eis
Keyword(s):  
Mineral Soil ◽  
Soil Surface ◽  
White Spruce ◽  
First Year ◽  
Height Increment ◽  
Undisturbed Soil ◽  
Nursery Stock ◽  
Survival And Development ◽  
Survival And Growth ◽  
Second Year

Survival and development of outplanted 2-0 and 2-1 white spruce nursery stock, transplanted 3-0 and 4-0 wildlings and 3-0 and 4-0 undisturbed wildlings are compared. Mortality was negligible in all groups. Planting check caused a 47% reduction in height increment during the first year and 15% during the second year after planting. The height increment was best related to the height growth during the previous year and total height of the planting stock. Insignificant differences were found between plants on undisturbed soil surface and those on exposed mineral soil.

scholarly journals Hydrologic Response of Meadow Restoration the First Year Following Removal of Encroached Conifers

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 428 ◽  
Author(s):  
Christopher Surfleet ◽  
Thomas Sanford ◽  
Gregory VanOosbree ◽  
John Jasbinsek
Keyword(s):  
Soil Moisture ◽  
Water Table ◽  
Growing Season ◽  
Bare Soil ◽  
Subsurface Water ◽  
First Year ◽  
Hydrologic Response ◽  
Before And After ◽  
Hydrologic Change ◽  
Montane Meadow

This study examines the hydrologic response of a montane meadow the first winter following restoration by removal of encroached conifers. Hydrologic change was evaluated through statistical comparison of soil moisture and water table depths between the restored meadow, Marian Meadow, and a Control Meadow before and after restoration. Meadow water budgets and durations of water table depths during the growing season were evaluated. Electrical resistivity tomography profiles were collected to improve the spatial interpretation of subsurface water beyond well measurements. The first year following restoration Marian Meadow had a statistically significant increase in volumetric soil moisture content of 4% with depth to the water table decreasing on average by 0.15 m. The water budget for the meadows demonstrated that the hydrologic change following removal of encroached conifers was primarily due to a reduction of vegetation interception capture. Soil evapotranspiration rates in both the Control and Marian Meadows were relatively stable ranging from 268–288 mm/yr with the exception of the year following conifer removal in Marian Meadow with 318 mm/yr. The increase in soil evapotranspiration in the first post restoration year is attributed to loss of vegetation cover and higher proportions of bare soil created from the harvest operations. The duration of post-restoration water table depths during the growing season at Marian Meadow were less than or equal to 0.7 m and 0.3 m for 85 days and 50 days, respectively, indicating hydrologic conditions conducive to meadow vegetation.

Growth in a Population of the Crayfish Pacifastacus leniusculus from a Subalpine Lacustrine Environment

1975 ◽  
Vol 32 (12) ◽  
pp. 2433-2440 ◽  
Author(s):  
R. Warren Flint
Keyword(s):  
Lake Tahoe ◽  
Growing Season ◽  
Growth Increment ◽  
Pacifastacus Leniusculus ◽  
First Year ◽  
Size Distributions ◽  
Age Classes ◽  
Growth Season ◽  
Growth Increments ◽  
Subalpine Lake

Observations on growth increments at each molt in a population of Pacifastacus leniusculus from a subalpine lake were made from periodically recaptured marked crayfish, as well as from molts recorded in the laboratory. After the first growing season the growth increment at molt remained relatively constant. Throughout the life of this crustacean no differences were observed between sexes. Analysis of size distributions in samples taken at different times of the year revealed that between 8 and 12 year-classes were normally present in the population of Lake Tahoe. Growth of these age-classes could be followed through consecutive samples. The number of molts completed by each year-class was found by relating data on growth increment per molt to growth shown in consecutive quantitative samples. Mean carapace length at recruitment for juvenile crayfish was 3.75 mm with 11 molts occurring during the first growing season, and juveniles reached 13.0 mm by the end of their first year. Molt frequency decreased in successive year-classes, and crayfish surviving past their fourth growth season molted only once a year. Length–weight relationships were similar for both sexes of the population even though their external anatomy differed. Growth comparison between this population and that of a coastal stream population showed that the stream population had a slightly faster overall growth rate due to higher water temperatures and a longer growing season.

scholarly journals Growth, Development and Ornamental Value of Miscanthus sinensis (Andersson) Species Depending on the Dose of Shrimp Biowaste

Agriculture ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 67
Author(s):  
Piotr Żurawik
Keyword(s):  
High Salinity ◽  
Mineral Soil ◽  
Growing Season ◽  
Miscanthus Sinensis ◽  
Alkaline Ph ◽  
Important Group ◽  
Planting Material ◽  
Miscanthus Giganteus ◽  
Before And After ◽  
Marine Products

Crustaceans, including shrimps, are an important group of marine products processed in over 50 countries around the world. It is one of the most profitable and fast-growing processing branches. About 30 to 40% of crustaceans are used immediately after fishing, while 60–70% are processed. This generates thousands of tons of waste, proper management of which becomes increasingly important. The study was conducted in the years 2015–2017. Planting material included rhizomes of Miscanthus sinensis and Miscanthus × giganteus. Shrimp shells, dried and fragmented into 2–3 mm long pieces, were added to the soil at a dose of 5%, 10% and 15%. Mineral soil without the dried waste served as control. pH and substrate salinity were determined both before and after the growing season, and vegetative and generative traits of the plants were assessed. Shrimp biowaste is rich in N, P, K, Ca and Mg, has alkaline pH and high salinity. Its effects on plants depend on its dose and plant species. Miscanthus sinensis turned out more sensitive to the substrate salinity but in both species shrimp biowaste improved their ornamental value. For Miscanthus sinensis the most beneficial dose was 5%, while for Miscanthus × giganteus it was 15%.

Coronary Care in a General Hospital

1971 ◽  
Vol 16 (3) ◽  
pp. 173-182 ◽  
Author(s):  
Gavin Shaw ◽  
Bernard Groden ◽  
Evelyn Hastings
Keyword(s):  
Myocardial Infarction ◽  
Intensive Care Unit ◽  
Intensive Care ◽  
General Hospital ◽  
First Year ◽  
Duration Of Stay ◽  
Before And After ◽  
The Mean ◽  
Coronary Care ◽  
Made In

The establishment, staffing and structure and observations made in the first year of the existence of coronary care in an intensive care unit in a general hospital are recorded. Two hundred and twenty eight patients were admitted during the year in whom the diagnosis of myocardial infarction was confirmed. There were 29 deaths in the unit and 14 deaths occurred in the wards of the hospital after discharge from the unit. 49.1 per cent of the patients were admitted within 4 hours of the onset of symptoms and the mean duration of stay in the unit was 86.5 hours. The type of arrhythmia detected in the unit, and the treatment given to the patients both before and after admission to the intensive care unit are described.

Bacterioplankton, Phytoplankton, and Zooplankton Communities in a British Columbia Coastal Lake Before and After Nutrient Reduction

1986 ◽  
Vol 43 (8) ◽  
pp. 1504-1514 ◽  
Author(s):  
F. Joan Hardy ◽  
Ken S. Shortreed ◽  
John G. Stockner
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Inorganic Nitrogen ◽  
Size Fraction ◽  
Growing Season ◽  
Nutrient Reduction ◽  
Nitrogen And Phosphorus ◽  
Coastal Lake ◽  
Before And After ◽  
High Concentrations

Inorganic nitrogen and phosphorus were applied weekly during the growing season from 1980 to 1982 and twice weekly in 1983 to Hobiton Lake, a warm monomictic coastal lake in British Columbia. The lake was not fertilized in 1984. Average numbers of bacteria during the growing season decreased from a high of 1.53 × 106∙mL−1 in the fertilized condition to 0.84 × 106∙mL−1 in the unfertilized condition. Chlorophyll a concentrations decreased from a maximum seasonal average of 2.69 μg∙L−1 (1981) to 1.30 μg∙L−1 (1984), and algal numbers decreased from 5.83 × 104∙mL−1 (1983) to 2.29 × 104∙mL−1 (1984). Although the numbers of phytoplankton in each size fraction (picoplankton, nanoplankton, or microplankton) decreased in the unfertilized condition, the greatest change was an almost fourfold decrease in picoplankton, which consisted of 90% cyanobacteria (primarily Synechococcus spp.). Abundance of the large diatoms Rhizosolenia spp. and Melosira spp. increased in 1984, resulting in an increase in average seasonal algal volume. Average densities of medium (0.15–0.84 mm) and large (0.85–1.5 mm) zooplankton were greatest in 1982, while rotifers and small zooplankton (0.10–0.14 mm) were most dense in 1984 following nutrient reduction. The lake had relatively high concentrations of planktivorous juvenile sockeye salmon (Oncorhynchus nerka) that appeared to minimize any direct effect of nutrient additions on zooplankton densities.

OP08 Levels and sources of stress reported by first year paramedic students associated with their first ambulance placement

2021 ◽  
Vol 38 (9) ◽  
pp. A4.2-A4
Author(s):  
Matthew Warren-James ◽  
Julie Hanson ◽  
Belinda Flanagan ◽  
Mary Katsikitis ◽  
Bill Lord
Keyword(s):  
Death And Dying ◽  
Educational Interventions ◽  
Fear Of Failure ◽  
Anxiety And Depression ◽  
Control Group ◽  
First Year ◽  
Before And After ◽  
Quasi Experimental ◽  
And Control ◽  
Experimental Group

BackgroundWhilst there is evidence to suggest paramedics experience significant stress when working in the ambulance setting little is known about the experiences of first year paramedic students. This research aimed to: (i) identify whether levels of stress, anxiety and depression experienced by first year paramedic students changed after ambulance placement compared to a control group, and (ii) identify the main perceived and actual sources of stress around ambulance placement.MethodsA before-and-after quasi-experimental design was used to compare whether the experience of ambulance placement altered the levels of stress, anxiety and depression in an experimental group that attended an ambulance placement (n = 20) and the control group who did not (n = 10). Online surveys encompassing the Depression, Anxiety and Stress Scale (DASS-21) and qualitative questions about sources of stress were concurrently deployed to both the experimental and control groups before and after the ambulance placement. Participants were first year paramedic students working in Queensland Ambulance Service, Australia.ResultsThere was a significant reduction in levels of stress in participants after undertaking their first ambulance placement (Mdn = -4.00) when compared to a control group (Mdn = 0.00), U = 52.5, p = .035, n2 = 0.15. Responses to survey questions suggest anticipation about experiencing death and dying of patients was the most frequently reported stressor of student paramedics before undertaking ambulance placements, however insecurity about knowledge, competence and fear of failure was the most frequently experienced stressor reported after completing ambulance placements.ConclusionsThe findings from this study suggest that the fear of the unknown may be worse than the reality. Anticipatory stress is the foremost problem for first year paramedic students attending their first ambulance placement. Placement pre-briefing should focus on educational interventions to build knowledge and skills competency to reduce stress levels and fear of failure.

Hydrological implications of vegetation change in a subarctic, alpine catchment, Yukon Territory, Canada 

2021 ◽  
Author(s):  
Erin Nicholls ◽  
Gordon Drewitt ◽  
Sean Carey
Keyword(s):  
Soil Moisture ◽  
Interannual Variability ◽  
Sap Flow ◽  
Vegetation Change ◽  
Vegetation Type ◽  
Growing Season ◽  
White Spruce ◽  
Yukon Territory ◽  
Precipitation Regimes ◽  
Tall Shrub

<p>As a result of altitude and latitude amplified impacts of climate change, widespread alterations in vegetation composition, density and distribution are widely observed across the circumpolar north. The influence of this vegetation change on the timing and magnitude of hydrological fluxes is uncertain, and is confounded by changes driven by increased temperatures and altered precipitation (P) regimes. In northern alpine catchments, quantification of total evapotranspiration (ET) and evaporative partitioning across a range of elevation-based ecosystems is critical for predicting water yield under change, yet remains challenging due to coupled environmental and phenological controls on transpiration (T). In this work, we analyze 6 years of surface energy balance, ET, and sap flow data at three sites along an elevational gradient in a subarctic, alpine catchment near Whitehorse, Yukon Territory, Canada. These sites provide a space-for-time evaluation of vegetation shifts and include: 1) a low-elevation boreal white spruce forest (~20 m), 2) a mid-elevation subalpine taiga comprised of tall willow (Salix) and birch (Betula) shrubs (~1-3 m) and 3) a high-elevation subalpine taiga with shorter shrub cover (< 0.75 m) and moss, lichen, and bare rock. Specific objectives are to 1) evaluate interannual ET dynamics within and among sites under different precipitation regimes , and 2) assess the influence of vegetation type and structure, phenology, soil and meteorological controls on ET dynamics and partitioning.  Eddy covariance and sap flow sensors operated year-round at the forest and during the growing season at the mid-elevation site on both willow and birch shrubs for two years. Growing season ET decreased and interannual variability increased with elevation, with June to August ET totals of 250 (±3) mm at Forest, 192 (±9) mm at the tall shrub site, and 180 (± 26) mm at the short shrub site. Comparatively, AET:P ratios were the highest and most variable at the forest (2.4 ± 0.3) and similar at the tall and short shrub (1.2 ± 0.1).  At the forest, net radiation was the primary control on ET, and 55% was direct T from white spruce. At the shrub sites, monthly ET rates were similar except during the peak growing season when T at the tall shrub site comprised 89% of ET, resulting in greater total water loss. Soil moisture strongly influenced T at the forest, suggesting the potential for moisture stress, yet not at the shrub sites where there was no moisture limitation. Results indicate that elevation advances in treeline will increase overall ET and lower interannual variability; yet the large water deficit during summer implies a strong reliance on early spring snowmelt recharge to sustain soil moisture. Changes in shrub height and density will increase ET primarily during the mid-growing season. This work supports the assertion that predicted changes in vegetation type and structure will have a considerable impact on water partitioning in northern regions, and will also vary in a multifaceted way in response to changing temperature and P regimes.  </p>

Prenatal Sonographic Head Circumference and Cerebral Ventricle Width Measurements Before and After Open Fetal Myelomeningocele Repair – Prediction of Shunting During the First Year of Life

2018 ◽  
Vol 41 (05) ◽  
pp. 544-549 ◽  
Author(s):  
Ladina Vonzun ◽  
Franziska Maria Winder ◽  
Martin Meuli ◽  
Ueli Moerlen ◽  
Luca Mazzone ◽  
...  
Keyword(s):  
Head Circumference ◽  
Predictive Accuracy ◽  
False Positive Rate ◽  
Roc Curves ◽  
First Year ◽  
Fetal Head ◽  
Fetal Diagnosis ◽  
Before And After ◽  
Width Measurements ◽  
First Year Of Life

Abstract Purpose The aim of this study was to describe the sonographic evolution of fetal head circumference (HC) and width of the posterior horn of the lateral ventricle (Vp) after open fetal myelomeningocele (fMMC) repair and to assess whether pre- or postoperative measurements are helpful to predict the need for shunting during the first year of life. Patients & Methods All 30 children older than one year by January 2017 who previously had fMMC repair at the Zurich Center for Fetal Diagnosis and Therapy were included. Sonographic evolution of fetal HC and Vp before and after fMMC repair was assessed and compared between the non-shunted (N = 16) and the shunted group (N = 14). ROC curves were generated for the fetal HC Z-score and Vp in order to show their predictive accuracy for the need for shunting until 1 year of age. Results HC was not an independent factor for predicting shunting. However, the need for shunting was directly dependent on the preoperative Vp as well as the Vp before delivery. A Vp > 10 mm at evaluation for fMMC repair or > 15 mm before delivery identifies 100 % of the infants needing shunt placement at a false-positive rate of 44 % and 25 %, respectively. All fetuses with a Vp > 15 mm at first evaluation received a shunt. Conclusion Fetuses demonstrating a Vp of > 15 mm before in utero MMC repair are extremely likely to develop hydrocephalus requiring a shunt during the first year of life. This compelling piece of evidence must be appropriately integrated into prenatal counseling.

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