Transfer of elements to the atmosphere during low-intensity prescribed fires in three Australian subalpine eucalypt forests

1985 ◽  
Vol 15 (4) ◽  
pp. 657-664 ◽  
Author(s):  
R. J. Raison ◽  
P. K. Khanna ◽  
P. V. Woods
Keyword(s):  
Complete Recovery ◽  
Small Mass ◽  
Prescribed Fires ◽  
Prescribed Burns ◽  
Low Intensity ◽  
Percentage Loss ◽  
The Difference ◽  
High Concentrations ◽  
Eucalypt Forests ◽  
Shrub Biomass

Measurements were made of the transfer of N,P,K, Ca, Mg, Mn, and B to the atmosphere during low-intensity (350–600 kWm−1) prescribed burns in three Australian subalpine eucalypt forests dominated by overstoreys of either Eucalyptuspauciflora (Sieb. ex Spreng), Eucalyptusdives (Schau.), or Eucalyptusdelegatensis (R. T. Baker). Elemental transfer was calculated as the difference between the quantity of an element in the fuel (litter plus understorey) before burning and that present in the postfire residues which were recovered quantitatively using small aluminium trays. Complete recovery of fine ash is essential for accurate budgeting for elements other than N. The mass ranges of elements transferred to the atmosphere (kilograms per hectare) were as follows: N, 74–109; P, 1.96–3.04; K, 12.1–21.0; Ca, 18.7–29.7; Mg, 4.5–9.7; Mn, 1.6–4.3; B, 0.08–0.12. These transfers represented, as a percentage of the element initially present in the fuel, the following: N, 54–75; P, 37–50, K, 43–66; Ca, 31–34; Mg, 25–49; Mn, 25–43; B, 35–54. The percentage loss of elements was positively linearly correlated with the percentage loss in fuel weight. High concentrations of P and cations occur in fine ash, especially grey (mineral) ash. In comparison with unburnt litter, concentrations of Ca, Mg, and P were increased by 10- to 50-fold, 10- to 35-fold, and 10-fold in fine (<1 mm) ash produced at the E. pauciflora site, respectively. Hence, transport of a relatively small mass of fine ash either during or after a fire may result in the removal of a significant quantity of nutrients. Prescribed fire rotations of about 10–12 years are required in the forests studied to permit natural inputs of N to approximately replace the amounts transferred to the atmosphere in a single fire. For P replacement, rotation length would need to exceed 20 years. The major impact of regular burning would appear to be on the N cycle because of the rapid reaccumulation of N in shrub biomass and surface litter, thus rendering it highly susceptible to volatilization in a subsequent burn.

The metachor as a characteristic of the association of electrolytes in aqueous solutions

1984 ◽  
Vol 49 (5) ◽  
pp. 1061-1078 ◽  
Author(s):  
Jiří Čeleda ◽  
Stanislav Škramovský
Keyword(s):  
Aqueous Solutions ◽  
Apparent Volume ◽  
Solutions Of Electrolytes ◽  
Molal Volumes ◽  
The Difference ◽  
High Concentrations ◽  
Experimental Values ◽  
Suitable Characteristic ◽  
Association Of Ions ◽  
Very High

Based on the earlier paper introducing a concept of the apparent parachor of a solute in the solution, we have eliminated in the present work algebraically the effect which is introduced into this quantity by the additivity of the apparent molal volumes. The difference remaining from the apparent parachor after substracting the contribution corresponding to the apparent volume ( for which the present authors suggest the name metachor) was evaluated from the experimental values of the surface tension of aqueous solutions for a set of 1,1-, 1,2- and 2,1-valent electrolytes. This difference showed to be independent of concentration up to the very high values of the order of units mol dm-3 but it was directly proportional to the number of the free charges (with a proportionality factor 5 ± 1 cm3 mol-1 identical for all studied electrolytes). The metachor can be, for this reason, a suitable characteristic for detection of the association of ions and formation of complexes in the solutions of electrolytes, up to high concentrations where other methods are failing.

scholarly journals Prescribed burning in a mediterranean-climate region mitigates the disturbance by bushfire to a critical food resource for an endangered bird, the Carnaby’s cockatoo

Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Valerie S. Densmore ◽  
Emma S. Clingan
Keyword(s):  
Seed Production ◽  
Prescribed Burning ◽  
Fire Regime ◽  
Fire Hazard ◽  
Food Resource ◽  
Management Tool ◽  
Fire Intensity ◽  
Prescribed Burns ◽  
Low Intensity ◽  
Percentage Survival

Abstract Background Prescribed burning is used to reduce fire hazard in highly flammable vegetation types, including Banksia L.f. woodland that occurs on the Swan Coastal Plain (SCP), Western Australia, Australia. The 2016 census recorded well over 1.9 million people living on the SCP, which also encompasses Perth, the fourth largest city in Australia. Banksia woodland is prone to frequent ignitions that can cause extensive bushfires that consume canopy-stored banksia seeds, a critical food resource for an endangered bird, the Carnaby’s cockatoo (Calyptorynchus latirostris, Carnaby 1948). The time needed for banksias to reach maturity and maximum seed production is several years longer than the typical interval between prescribed burns. We compared prescribed burns to bushfires and unburned sites at three locations in banksia woodland to determine whether low-intensity prescribed burns affect the number of adult banksias and their seed production. Study sites were matched to the same vegetation complex, fire regime, and time-since-fire to isolate fire intensity as a variable. Results Headfire rates of spread and differenced normalized burn ratios indicated that prescribed burning was generally of a much lower intensity than bushfire. The percentage survival of adult banksias and their production of cones and follicles (seeds) did not decrease during the first three years following a prescribed burn. However, survival and seed production were significantly diminished followed high-intensity bushfire. Thus, carrying capacity for Carnaby’s cockatoo was unchanged by prescribed burning but decreased markedly following bushfire in banksia woodland. Conclusions These results suggest that prescribed burning is markedly different from bushfire when considering appropriate fire intervals to conserve canopy habitats in fire-resilient vegetation communities. Therefore, low-intensity prescribed burning represents a viable management tool to reduce the frequency and extent of bushfire impacts on banksia woodland and Carnaby’s cockatoo.

scholarly journals Heterotopic ossification in the post cruciate ligament of the knee: a case report and literature review

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Cun Li ◽  
Zonggui Huang ◽  
K. C. Anil ◽  
Chendeng Lao ◽  
Qianghua Wu ◽  
...  
Keyword(s):  
Literature Review ◽  
Heterotopic Ossification ◽  
Knee Pain ◽  
Cruciate Ligament ◽  
Complete Recovery ◽  
X Rays ◽  
Related Factors ◽  
Knee Motion ◽  
Adequate Treatment ◽  
The Difference

Abstract Background Heterotopic ossification (HO) is noted most frequently in periarticular muscles and has not yet been reported in the cruciate ligaments of the knee. We present a rare case of symptomatic ossification of the posterior cruciate ligament (PCL). Case presentation A 59-year-old woman had a 2-year history of knee pain that was getting worse during knee motion and had restricted knee motion for 1 year. X-rays could not show the lesion clearly. Multi-planar computed tomography demonstrated ossification within the PCL with mild osteoarthritic changes and excluded any other intra-articular pathology. The patient underwent arthroscopic debridement and then experienced immediate relief of pain and complete recovery of range of motion. Conclusion This is the first report of HO in the PCL as a possible cause of knee pain and restricted knee motion. On the basis of literature review, this case elaborates the difference between HO and calcification in the ligaments, the related factors inducing HO and the undefined pathogenesis, and favorable prognosis after adequate treatment.

scholarly journals Thunderstorm outflows preceding epidemics of asthma during spring and summer

Thorax ◽  
2001 ◽  
Vol 56 (6) ◽  
pp. 468-471
Author(s):  
G B Marks ◽  
J R Colquhoun ◽  
S T Girgis ◽  
M Hjelmroos Koski ◽  
A B A Treloar ◽  
...  
Keyword(s):  
Pollen Grains ◽  
Ground Level ◽  
Fold Increase ◽  
Underlying Mechanism ◽  
Detailed Examination ◽  
Asthma Exacerbations ◽  
Eastern Australia ◽  
The Difference ◽  
High Concentrations ◽  
Thunderstorm Outflow

BACKGROUNDA study was undertaken to assess the importance of thunderstorms as a cause of epidemics of asthma exacerbations and to investigate the underlying mechanism.METHODSA case control study was performed in six towns in south eastern Australia. Epidemic case days (n = 48) and a random sample of control days (n = 191) were identified by reference to the difference between the observed and expected number of emergency department attendances for asthma. The occurrence of thunderstorms, their associated outflows and cold fronts were ascertained, blind to case status, for each of these days. In addition, the relation of hourly pollen counts to automatic weather station data was examined in detail for the period around one severe epidemic of asthma exacerbations. The main outcome measure was the number of epidemics of asthma exacerbations.RESULTSThunderstorm outflows were detected on 33% of epidemic days and only 3% of control days (odds ratio 15.0, 95% confidence interval 6.0 to 37.6). The association was strongest in late spring and summer. Detailed examination of one severe epidemic showed that its onset coincided with the arrival of the thunderstorm outflow and a 4–12 fold increase in the ambient concentration of grass pollen grains.CONCLUSIONSThese findings are consistent with the hypothesis that some epidemics of exacerbations of asthma are caused by high concentrations of allergenic particles produced by an outflow of colder air, associated with the downdraught from a thunderstorm, sweeping up pollen grains and particles and then concentrating them in a shallow band of air at ground level. This is a common cause of exacerbations of asthma during the pollen season.

scholarly journals Gas-Phase Pyrolysis Products Emitted by Prescribed Fires in Pine Forests with a Shrub Understory in the Southeastern United States

2019 ◽  
Author(s):  
Nicole K. Scharko ◽  
Ashley M. Oeck ◽  
Tanya L. Myers ◽  
Russell G. Tonkyn ◽  
Catherine A. Banach ◽  
...  
Keyword(s):  
Gas Phase ◽  
Pine Forests ◽  
Prescribed Fires ◽  
Pyrolysis Products ◽  
Prescribed Burns ◽  
Extraction Device ◽  
Dominant Process ◽  
Pyrolysis Gases ◽  
Manual Extraction ◽  
Emission Ratios

Abstract. In this study we capture and identify pyrolysis gases from prescribed burns conducted in pine forests with a shrub understory using a manual extraction device. The device selectively sampled emissions ahead of the flame front, minimizing collection of oxidized gases, with the captured gases analyzed in the laboratory using infrared absorption spectroscopy. Results show that emission ratios (ER) relative to CO for ethene, and acetylene were significantly greater than previous fire studies, suggesting that the sample device was able to collect gases prior to ignition. Further evidence that ignition had not begun was corroborated by novel infrared detections of several species, in particular naphthalene. With regards to oxygenated species, several aldehydes (acrolein, furaldehyde, acetaldehyde, formaldehyde) and the carboxylic acids (formic, acetic) were all observed; results show that ERs for acetaldehyde were noticeably greater while ERs for formaldehyde and acetic acid were lower compared to other studies. The acetylene-to-furan ratio also suggests that high temperature pyrolysis was the dominant process generating the collected gases. This hypothesis is further supported by the presence of HCN and the absence of NH3.

The influence of hydrological pathways on the transport of the herbicide, isoproturon, through an underdrained clay soil

1999 ◽  
Vol 39 (12) ◽  
pp. 77-84 ◽  
Author(s):  
C. M. Heppell ◽  
T. P. Burt ◽  
R. J. Williams ◽  
A. H. Haria
Keyword(s):  
Surface Waters ◽  
Clay Soil ◽  
Quality Standard ◽  
Early Spring ◽  
Hydrological Response ◽  
Macropore Flow ◽  
Ephemeral Stream ◽  
Low Intensity ◽  
Flow Through ◽  
High Concentrations

This paper reports the findings of a 12 month field monitoring programme at Wytham (Oxfordshire, UK), which examined the leaching of the phenylurea herbicide, isoproturon, from an agricultural clay hillslope to the adjacent ephemeral stream. Isoproturon was shown to reach the drains (at 50 cm depth) through a combination of vertical and lateral macropore flow through wormholes and inter-pedal cracks. Seasonal changes in hydrological response were also observed at the site, with lateral flow through inter-pedal cracks providing an important route by which herbicide was transported during autumn and early spring when the clay soils were wetting up. Concentrations of isoproturon in drainflow frequently exceeded the Environment Agency's (EA) non-statutory Environmental Quality Standard (EQS) of 20 μg/l for isoproturon in surface waters. Even under low intensity rainfall (&lt; 1 mm/hr) the saturated region at the base of the hillslope was shown to conduct macropore flow containing significantly high concentrations of herbicide to the drain. The results of this study suggest that those regions close to surface waters which are areas of converging hydrological flow may be key contributors to the problem of isoproturon contamination of surface waters.

BIOFEED BACK THERAPY AND CYTOFLAVIN IN THE SYSTEM OF MEDICAL SUPPORT OF THE TRAINING PROCESS OF ELDERLY HOCKEY PLAYERS

2021 ◽  
pp. 306-310
Author(s):  
А. А. Елькин ◽  
Ю. А. Парфенов ◽  
С. А. Парфенов ◽  
К.В. Сапожников ◽  
А. Л. Коваленко ◽  
...  
Keyword(s):  
Functional State ◽  
Effective Means ◽  
Complete Recovery ◽  
The Elderly ◽  
Biofeedback Training ◽  
Medical Support ◽  
Training Process ◽  
Hockey Players ◽  
The Difference ◽  
Methodological Aspects

Одним из направлений улучшения состояния пожилого человека является методика аутотренинга с биологической обратной связью как средство коррекции отклонений функционирования регуляторного аппарата, а также усиление антиоксидантной защиты и элиминация последствий оксидативного стресса при помощи терапии Цитофлавином. Указанные методики представляются простым и эффективным средством коррекции негативных изменений функционального состояния у пожилых хоккеистов после цикла тренировок и обеспечение возможности более полного восстановления их организма. Разность точек приложения позволила объединить приём Цитофлавина и БОС-тренинга в единую комплексную коррекционно-восстановительную методику. Цель исследования - рассмотрение организационно-методических аспектов внедрения комплексной методики коррекции функционального состояния пожилых хоккеистов в систему сопровождения их тренировочного процесса. По результатам проведенного исследования получены убедительные данные о положительном эффекте включения Цитофлавина и БОС-тренинга в систему медицинского сопровождения тренировочного процесса у пожилых хоккеистов. Рассмотренные в настоящей статье организационнометодические аспекты внедрения комплексной методики коррекции функционального состояния пожилых хоккеистов в систему сопровождения их тренировочного процесса позволяют решить ряд задач, стоящих перед медицинскими работниками, касающихся непрерывного мониторинга состояния организма пожилых хоккеистов, упреждающей диагностики его негативных отклонений, а также системы коррекционно-восстановительных мер. One of the ways to improve the condition of the elderly body is the method of auto-training with biofeedback, as a means of correcting deviations in the functioning of the regulatory apparatus, as well as improving antioxidant protection and eliminating the effects of oxidative stress using Cytoflavin therapy. These methods seem to be a simple and effective means of correcting negative changes in the FS of elderly hockey players after a training cycle and ensuring the possibility of a more complete recovery of their body. The difference in the points of application made it possible to combine the intake of Cytoflavin and biofeedback training into a single complex correctional and restorative technique. Purpose of the research: to consider the organizational and methodological aspects of introducing a comprehensive methodology for correcting the functional state of elderly hockey players into the system of support of their training process. Based on the results of the study, we have obtained convincing data on the positive effect of the inclusion of Cytoflavin and biofeedback training in the system of medical support for the training process of elderly hockey players. The organizational and methodological aspects of introducing a comprehensive methodology for correcting the functional state of older hockey players into the system of support for their training process considered in this article make it possible to solve a number of problems facing medical workers regarding continuous monitoring of the functional state of older hockey players, proactive diagnosis of their negative deviations, as well as a system of reabilitation.

Teaching First Aid, CPR, and AED Using Blended Learning in Academic Settings

2018 ◽  
pp. 325-339
Author(s):  
Jerono P. Rotich ◽  
Gloria Elliott
Keyword(s):  
Blended Learning ◽  
Online Courses ◽  
Heart Association ◽  
Complete Recovery ◽  
First Aid ◽  
Red Cross ◽  
College Age ◽  
Safety And Health ◽  
Academic Settings ◽  
The Difference

Due to the increase of accidents, incidences, and unexpected emergencies, knowledge of first aid, CPR, and AED skills is critical. It can make the difference between life and death and between complete recovery and permanent disability. Although numerous agencies such as the American Red Cross, American Safety and Health and Institute (ASHI), American Heart Association (AHA), and other organizations have trained millions of individuals in first aid, CPR, and AED, there is still a need to train more people especially the college age population. This chapter examines the need and impact of teaching first aid, CPR, and AED through blended learning in a college or university setting. Benefits of blended and online courses as well as strategies for setting up and teaching a blended learning course are provided.

scholarly journals Concentrations and Loads of Dissolved and Particulate Organic Carbon in Urban Stormwater Runoff

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1031 ◽  
Author(s):  
Stefan Kalev ◽  
Gurpal S. Toor
Keyword(s):  
Organic Carbon ◽  
Stormwater Runoff ◽  
Light Availability ◽  
Rain Gauge ◽  
Urban Landscapes ◽  
Storm Events ◽  
Wet Season ◽  
The Difference ◽  
Urban Stormwater Runoff ◽  
High Concentrations

Urban landscapes are significant contributors of organic carbon (OC) in receiving waters, where elevated levels of OC limit the light availability, increase the transport of pollutants, and result in high costs of potable water treatment. Our objective in this study was to investigate the concentrations, fractions (dissolved and particulate), and loads of OC in a residential catchment (3.89 ha drainage area) located in Florida, United States. The outlet of the stormwater pipe draining the residential catchment was instrumented with an automated sampler, a flowmeter, and a rain gauge. The rainfall and runoff samples collected over 25 storm events during the 2016 wet season (June to September) were analyzed for dissolved organic carbon (DOC) and total organic carbon (TOC), with particulate OC (POC) calculated as the difference between TOC and DOC. Mean concentration of DOC was 2.3 ± 1.7 mg L−1 and POC was 0.3 ± 0.3 mg L−1 in the rainfall, whereas DOC was 10.5 ± 6.20 mg L−1 and POC was 2.00 ± 4.05 mg L−1 in the stormwater runoff. Concentrations of DOC were higher during the rising limb of the hydrograph in 15 out of 25 storm events, suggesting flushing of DOC, with an increase in the amount of runoff, from the landscape sources in the residential catchment. The estimated total export of OC during the 2016 wet season was 66.0 kg ha−1, of which DOC was 56.9 kg ha−1 (86.2% of TOC), and POC was 9.1 kg ha−1 (13.8% of TOC). High concentrations and loads of OC, especially DOC, in the stormwater runoff imply that residential catchments in urban watersheds are hot-spots of DOC influx to water bodies. Reducing DOC transport in the urban landscapes is complex and require identifying the origin of DOC and then using site-specific targeted approaches to mitigate DOC loss.

scholarly journals Simulation Comparisons of Particulate Emissions from Fires under Marginal and Critical Conditions

Atmosphere ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 704 ◽  
Author(s):  
Alexander J. Josephson ◽  
Daniel Castaño ◽  
Marlin J. Holmes ◽  
Rodman R. Linn
Keyword(s):  
Particle Size ◽  
High Intensity ◽  
Particle Emission ◽  
Critical Conditions ◽  
Prescribed Fires ◽  
Particulate Emissions ◽  
Southeast United States ◽  
Low Intensity ◽  
High Winds ◽  
Fire Conditions

Using a particulate emissions model developed for FIRETEC, we explore differences in particle emission profiles between high-intensity fires under critical conditions and low-intensity fires under marginal conditions. Simulations were performed in a chaparral shrubland and a coniferous pine forest representative of the southeast United States. In each case, simulations were carried out under marginal and critical fire conditions. Marginal fire conditions include high moisture levels and low winds, often desired for prescribed fires as these conditions produce a low-intensity burn with slower spread rates. Critical fire conditions include low moisture levels and high winds, which easily lead to uncontrollable wildfires which produce a high-intensity burn with faster spread rates. These simulations’ resultant particle emission profiles show critical fire conditions generate larger particle emission factors, higher total mass emissions, and a higher lofting potential of particles into the atmosphere when compared against marginal fire conditions but similar particle size distrubtions. In addition, a sensitivity analysis of the emissions model was performed to evaluate key parameters which govern particle emission factor and particle size.

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