Soil respiration after slash and stump removal in three clear-cut areas with patch scarification and mounding

Quantification of the components of ecosystem respiration is essential to understanding carbon (C) cycling of natural and disturbed landscapes. Soil respiration, which includes autotrophic and heterotrophic respiration from throughout the soil profile, is the second largest flux in the global carbon cycle. We measured soil respiration (soil CO2 emission) at an undisturbed mature jack pine (Pinus banksiana Lamb.) stand in Saskatchewan (old jack pine, OJP), and at a formerly continuous portion of the stand that was clear-cut during the previous winter (clear-cut, CC). Tree harvesting reduced soil CO2 emission from ~22.5 to ~9.1 mol CO2 cdot m-2 for the 1994 growing season. OJP was a small net sink of atmospheric CO2, while CC was a net source of CO2. Winter emissions were similar at both sites. Reduction of soil respiration was attributed to disruption of the soil surface and to the death of tree roots. Flux simulations for CC and OJP identify 40% of CO2 emission at the undisturbed OJP site as near-surface respiration, 25% as deep-soil respiration, and 35% as tree-root respiration. The near-surface component was larger than the estimated annual C input to soil, suggesting fast C turnover and no net C accumulation in these boreal uplands in 1994.

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Soil respiration following Chinese fir plantation clear-cut: Comparison of two forest regeneration approaches

The Science of The Total Environment ◽

10.1016/j.scitotenv.2019.135980 ◽

2020 ◽

Vol 709 ◽

pp. 135980

Author(s):

Shangbin Bai ◽

Wanting Qiu ◽

Hui Zhang ◽

Yixiang Wang ◽

Frank Berninger

Keyword(s):

Soil Respiration ◽

Forest Regeneration ◽

Chinese Fir ◽

Clear Cut ◽

Chinese Fir Plantation

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Seasonal patterns of soil respiration in intact and clear-cut northern hardwood forests

Canadian Journal of Forest Research ◽

10.1139/x94-221 ◽

1994 ◽

Vol 24 (8) ◽

pp. 1711-1716 ◽

Cited By ~ 87

Author(s):

David E. Toland ◽

Donald R. Zak

Keyword(s):

Soil Respiration ◽

Root Respiration ◽

Microbial Respiration ◽

Late Summer ◽

Soda Lime ◽

Forest Harvesting ◽

Seasonal Patterns ◽

Soil C ◽

Northern Hardwood ◽

Clear Cut

The flux of CO2 from forest soils is controlled by the respiration of plant roots and soil microorganisms, the rates of which are likely to change following forest harvesting. Root respiration should decrease, whereas microbial respiration should increase, in response to warmer soil temperatures and greater soil C availability following removal of the overstory. We investigated the influence of forest harvesting on seasonal patterns of soil respiration in two different northern hardwood ecosystems. One ecosystem was dominated in the overstory by Acersaccharum Marsh, and Quercusrubra L., and the other by A. saccharum and Tiliaamericana L.; two stands were studied in each ecosystem type. We measured daily rates of soil respiration using the soda-lime technique. Averaged across ecosystems, daily rates of soil respiration did not significantly differ between intact and clear-cut plots, nor did they differ between ecosystems or sites nested within ecosystems. Peak daily rates ranged from 2.75 to 3.00 g CO2-C•m−2•day−1 during mid to late summer in both intact and clear-cut plots. Soil temperature accounted for 43 and 58% of the variation in daily rates for intact and clear-cut plots, respectively. Annual soil respiration rates in intact (478 g CO2-C•m−2•year−1) and clear-cut (470 g CO2-C•m−1•year−1) plots did not differ significantly. Our results suggest that greater rates of microbial respiration in clear-cut plots proportionally offset a decrease in root respiration following clear-cut harvest.

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Soil respiration and nitrogen leaching decreased in grey alder (Alnus incana (L.) Moench) coppice after clear-cut

Scandinavian Journal of Forest Research ◽

10.1080/02827581.2019.1610189 ◽

2019 ◽

Vol 34 (6) ◽

pp. 445-457

Author(s):

Jürgen Aosaar ◽

Mats Varik ◽

Hardo Becker ◽

Gunnar Morozov ◽

Kristiina Aun ◽

...

Keyword(s):

Soil Respiration ◽

Nitrogen Leaching ◽

Alnus Incana ◽

Clear Cut

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Soil respiration and photosynthetic uptake of carbon dioxide by ground-cover plants in four ages of jack pine forest

Canadian Journal of Forest Research ◽

10.1139/x01-092 ◽

2001 ◽

Vol 31 (9) ◽

pp. 1540-1550 ◽

Cited By ~ 18

Author(s):

Robert G Striegl ◽

Kimberly P Wickland

Keyword(s):

Carbon Dioxide ◽

Soil Respiration ◽

Land Surface ◽

Pinus Banksiana ◽

Ground Cover ◽

Jack Pine ◽

Stand Age ◽

Measured Flux ◽

Clear Cut ◽

Mature Stands

Soil carbon dioxide (CO2) emission (soil respiration), net CO2 exchange after photosynthetic uptake by ground-cover plants, and soil CO2 concentration versus depth below land surface were measured at four ages of jack pine (Pinus banksiana Lamb.) forest in central Saskatchewan. Soil respiration was smallest at a clear-cut site, largest in an 8-year-old stand, and decreased with stand age in 20-year-old and mature (6075 years old) stands during May September 1994 (12.1, 34.6, 31.5, and 24.9 mol C·m2, respectively). Simulations of soil respiration at each stand based on continuously recorded soil temperature were within one standard deviation of measured flux for 48 of 52 measurement periods, but were 10%30% less than linear interpolations of measured flux for the season. This was probably due to decreased soil respiration at night modeled by the temperature-flux relationships, but not documented by daytime chamber measurements. CO2 uptake by ground-cover plants ranged from 0 at the clear-cut site to 29, 25, and 9% of total growing season soil respiration at the 8-year, 20-year, and mature stands. CO2 concentrations were as great as 7150 ppmv in the upper 1 m of unsaturated zone and were proportional to measured soil respiration.

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Shoulder Pain at Work: Causation Analysis

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2017.janfeb02 ◽

2017 ◽

Vol 22 (1) ◽

pp. 11-16

Author(s):

Joel Weddington ◽

Charles N. Brooks ◽

Mark Melhorn ◽

Christopher R. Brigham

Keyword(s):

Epidemiological Data ◽

Case Law ◽

Individual Case ◽

Shoulder Injury ◽

Work Related ◽

Clear Cut ◽

The Individual ◽

Causation Analysis ◽

Injury Causation ◽

Relevant Factors

Abstract In most cases of shoulder injury at work, causation analysis is not clear-cut and requires detailed, thoughtful, and time-consuming causation analysis; traditionally, physicians have approached this in a cursory manner, often presenting their findings as an opinion. An established method of causation analysis using six steps is outlined in the American College of Occupational and Environmental Medicine Guidelines and in the AMA Guides to the Evaluation of Disease and Injury Causation, Second Edition, as follows: 1) collect evidence of disease; 2) collect epidemiological data; 3) collect evidence of exposure; 4) collect other relevant factors; 5) evaluate the validity of the evidence; and 6) write a report with evaluation and conclusions. Evaluators also should recognize that thresholds for causation vary by state and are based on specific statutes or case law. Three cases illustrate evidence-based causation analysis using the six steps and illustrate how examiners can form well-founded opinions about whether a given condition is work related, nonoccupational, or some combination of these. An evaluator's causal conclusions should be rational, should be consistent with the facts of the individual case and medical literature, and should cite pertinent references. The opinion should be stated “to a reasonable degree of medical probability,” on a “more-probable-than-not” basis, or using a suitable phrase that meets the legal threshold in the applicable jurisdiction.

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PET in patients with clear-cut multiple chemical sensitivity (MCS)

Nuklearmedizin ◽

10.1055/s-0038-1625294 ◽

2002 ◽

Vol 41 (06) ◽

pp. 233-239 ◽

Cited By ~ 6

Author(s):

C. Hausteiner ◽

A. Drzezga ◽

P. Bartenstein ◽

M. Schwaiger ◽

H. Förstl ◽

...

Keyword(s):

Single Photon ◽

Photon Emission ◽

Multiple Chemical Sensitivity ◽

Environmental Chemicals ◽

Chemical Sensitivity ◽

Clear Cut ◽

Positron Emission ◽

Symptom Complex ◽

Brain Changes ◽

Multiple Chemical

SummaryAim: Multiple chemical sensitivity (MCS) is a controversially discussed symptom complex. Patients afflicted by MCS react to very low and generally nontoxic concentrations of environmental chemicals. It has been suggested that MCS leads to neurotoxic damage or neuroimmunological alteration in the brain detectable by positron emission tomography (PET) and single photon emission computer tomography (SPECT). These methods are often applied to MCS patients for diagnosis, although they never proved appropriate. Method: We scanned 12 MCS patients with PET, hypothesizing that it would reveal abnormal findings. Results: Mild glucose hypometabolism was present in one patient. In comparison with normal controls, the patient group showed no significant functional brain changes. Conclusion: This first systematic PET study in MCS patients revealed no hint of neurotoxic or neuroimmuno-logical brain changes of functional significance.

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Effect of Anabolic Steroids on Plasma Antithrombin III

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651450 ◽

1975 ◽

Vol 34 (01) ◽

pp. 106-114 ◽

Cited By ~ 3

Author(s):

I. D Walker ◽

J. F Davidson ◽

P Young ◽

J. A Conkie

Keyword(s):

Heart Disease ◽

Ischaemic Heart Disease ◽

Oral Contraceptives ◽

Disseminated Intravascular Coagulation ◽

Fibrinolytic Activity ◽

Antithrombin Iii ◽

Anabolic Steroids ◽

Intravascular Coagulation ◽

Clear Cut ◽

Α2 Macroglobulin

SummaryThe effect of seven different anabolic steroids (Ethyloestrenol, Methenolone acetate, Norethandrolone, Methylandrostenediol, Oxymetholone, Methandienone, and Stanozolol) on three α-globulin antiprotease inhibitors of thrombin and plasmin was studied in men with ischaemic heart disease. In distinct contrast to the oral contraceptives, five of the six 17-α-alkylated anabolic steroids studied produced increased plasma Antithrombin III levels and five produced decreased levels of plasma α2-macroglobulin. The effect on plasma α1antitrypsin levels was less clear-cut but three of the steroids examined produced significantly elevated levels. The increased plasma fibrinolytic activity which the 17-α-alkylated anabolic steroids induce is therefore unlikely to be secondary to disseminated intravascular coagulation.

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Fibrinogen and Factor Vllag in Healthy Adolescents: The Floren-teen (Florence Teenager) Study

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650366 ◽

1996 ◽

Vol 75 (05) ◽

pp. 778-781 ◽

Cited By ~ 9

Author(s):

Domenico Prisco ◽

Sandra Fedi ◽

Tamara Brunelli ◽

Anna Paola Cellai ◽

Mohamed Isse Hagi ◽

...

Keyword(s):

Risk Factors ◽

Blood Pressure ◽

Healthy Subjects ◽

Cardiovascular Events ◽

Independent Risk Factor ◽

Factor Vii ◽

Coronary Heart Disease Prevention ◽

Familial History ◽

Clear Cut ◽

Adolescent Population

SummaryAt least five studies based on more than twenty thousand healthy subjects indicated that fibrinogen is an independent risk factor for cardiovascular events; less clear-cut is the relation between factor VII and risk for arterial thrombotic disorders, which was demonstrated in two of the three studies investigating this association. However, no study has investigated the behaviour of fibrinogen and factor VII in an adolescent population. In a study of Preventive Medicine and Education Program, fibrinogen (clotting method) and factor Vllag (ELISA), in addition to other metabolic parameters, life-style and familial history, were investigated in 451 students (313 females and 138 males, age 15-17 years) from two high schools of Florence. Fibrinogen levels were significantly higher in women than in men, whereas factor Vllag levels did not significantly differ. Both fibrinogen and factor Vllag significantly correlated with total cholesterol (p <0.05) while only fibrinogen correlated with body mass index (p <0.01). Factor Vllag was significantly correlated with systolic blood pressure (p <0.001). This study provides information on coagulation risk factors in a population of adolescents which may be of importance in planning coronary heart disease prevention programs.

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F.N.A.C. AS DIAGNOSTIC TOOL OF PAROTID TUMORS AND ASSOCIATED PITFALLS IN CORRELATION WITH HISTOPATHOLOGY

International Journal of Medical and Biomedical Studies ◽

10.32553/ijmbs.v4i1.1153 ◽

2020 ◽

Vol 4 (1) ◽

Author(s):

Bhawana Pant ◽

Sanjay Gaur ◽

Prabhat Pant

Keyword(s):

Preoperative Diagnosis ◽

Histopathological Examination ◽

Clinical Information ◽

Final Diagnosis ◽

Needle Aspiration ◽

Histopathological Diagnosis ◽

Cytological Diagnosis ◽

Tertiary Referral Centre ◽

Clear Cut ◽

Parotid Tumors

F.NA.C has been used for ages as a safe and economical tool for fast preoperative diagnosis of parotid tumors. It has certain pitfall which sometimes leads to misdiagnosis and consequently it may have affect on treatment of the tumors. Keeping in view of the diverse classification of parotid tumors’ information from cytology should be combined with radiology as well as clinical diagnosis. Aim: To discuss some cases where there was discrepancy between cytological diagnosis and histopathological result and also suggest measures to improve the efficacy of F.N.A.C. Material and methods: The study includes 50 cases of parotid tumours who presented to the department of ENT at Government medical college Haldwani which is a tertiary referral centre during 2009 to 2016. Only adult patients were included and inflammatory swelling were excluded from the study. All patients evaluated Contrast enhanced computerized tomography(CECT) and Magnetic resonance imaging (MRI) followed by Fine needle aspiration cytology .Preoperative diagnosis was made upon the findings of the above investigations and different types of parotid surgeries were done. . Final diagnosis was made on histopathological examination. Result :The most common tumour came out to be pleomorphic adenoma (23 cases-46%) followed by mucoepidermoid carcinoma(12cases-24%). In ten cases there was no clear cut association between cytological diagnosis and final histopathological diagnosis. Conclusion: FNAC is highly sensitive and specific technique for diagnosis of many salivary gland swellings. FNAC can be used preoperatively to avoid unnecessary surgery and biopsy. Details of clinical information and radiologic features may help the pathologist to arrive at the appropriate diagnosis and reduce false interpretation. Pitfalls may also occur with improper technique of FNAC which can be overcome by proper caution.

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