scholarly journals Forest fire survival in young, dense Betula ermanii stands on soil scarification sites

2020 ◽  
Author(s):  
Masato Hayamizu ◽  
Yasutaka Nakata ◽  
Hiroyuki Torita
Keyword(s):  
Forest Fire ◽  
Recovery Rate ◽  
Survival Rates ◽  
Rapid Change ◽  
Unmanned Aircraft ◽  
Dwarf Bamboo ◽  
Betula Ermanii ◽  
Trunk Diameter ◽  
Soil Scarification ◽  
Second Year

AbstractA forest fire in a cool-temperate broad-leaved forest in northern Japan, from 26 May to 19 June 2019, provided an opportunity to examine its effects on young and dense birch (Betula ermanii Cham.) stands in soil scarification sites. To characterise post-fire responses (survival and resprouting) of birch, we set up two plots, 6 months post fire. We investigated trunk diameter at breast height and burn marks on tree trunks (scorch height and charring percentage around the tree bole) of all B. ermanii trees in both plots. Survival and resprouting of each tree were monitored over 2 years (6 and 16 months post fire). To quantify post-fire vegetation recovery in the forest floor, we manually mapped the dominant understory plant, dwarf bamboo (i.e. Sasa kurilensis (Rupr.) Makino et Shibata), from orthomosaic images obtained by an unmanned aircraft vehicle, and estimated the recovery rate in the second year post fire. Additionally, seedlings of woody species were counted in both plots. Size-dependent survival rates of plants in both plots were similar in the first year post fire. All B. ermanii trees died without resprouting in the second year post fire, indicating the lethal effects of fire on young birch trees. Moreover, a high recovery rate of dwarf bamboos over 2 years in both plots and limited seedling establishment of woody plants suggest that the fire resulted in regeneration failure of young stands in the scarification sites. On the basis of these findings, we propose future management of stands in soil scarification sites post fire, considering the vulnerability of young trees and the rapid change in vegetation from young forest to dense birch cover post fire.

Small Group Discussion, an Effective Tool for Learning

2021 ◽  
Vol 15 (10) ◽  
pp. 3281-3283
Author(s):  
Farrukh Sarfraz ◽  
Nadeem Razaq ◽  
Fahad Sarfraz ◽  
Muhammad Saif Ullah ◽  
Imran Jawad ◽  
...  
Keyword(s):  
Small Group ◽  
Communication Skills ◽  
Group Dynamics ◽  
Group Discussion ◽  
Rapid Change ◽  
Small Group Discussion ◽  
Medical College ◽  
Constructive Feedback ◽  
Validated Questionnaire ◽  
Second Year

Introduction: With the rapid change in teaching methodologies small group discussion gained a lot of popularity due to its wide impact from multiple dimensions on the learning of students. It is not only influences the learning of the students but also polished many skills not previously explored by the student such as communication skills, leadership qualities, ethics of group dynamics, respect of views of peers and so many. Objective: To expedite the views of Second year MBBS students at Azra Naheed Medical College about Small group discussion. Material and Methods Study design: Quantitative, cross sectional study. Settings: Azra Naheed Medical College, Lahore. Duration: Six months i.e. 1st January 2021 to 30th June 2021. Data Collection procedure: This study is conducted at Azra Naheed Medical College, Lahore, a total of 150 students divided into 10 groups each comprising of 15 students participated in the study. Students and the facilitators were briefed about the study; the topic assigned to each group ware told them a couple of days before the session. Pre validated questionnaire from the department of medical education was used and the collected data was analyzed by using SPSS version 23. Research question: What is the perception of Second year MBBS students at Azra Naheed College, Lahore about small group discussion an effective tool for learning? Results: Majority of the students were satisfied with the punctuality, constructive feedback, role of facilitator, improvement in the communication skills, interaction and positive feedback. Conclusion: It concludes students learned how to maintain a good balance of the session. Our study provided enough opportunities to the students to focus on the dynamics of learning in a modern way of self-respect, respect to the peers, improved self-confidence, and importance of positive and constructive feedback and in the end how to summarize and conclude a session. Key words: small group discussion, student centered learning, integrated learning, lecture

scholarly journals Adaptation, Biometric Traits and Performances of Guayule Lines Grown in Two Mediterranean Environments

Agriculture ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 651
Author(s):  
Leonardo Sulas ◽  
Giuseppe Campesi ◽  
Simone Canu ◽  
Antonio M. Carroni ◽  
Antonio Dore ◽  
...  
Keyword(s):  
Survival Rate ◽  
Chlorophyll Concentration ◽  
Survival Rates ◽  
Photochemical Efficiency ◽  
Plant Survival ◽  
Trunk Diameter ◽  
Leaf Chlorophyll ◽  
Mediterranean Environments ◽  
Affected Plant ◽  
Perennial Shrub

The perennial shrub guayule (Parthenium argentatum A. Gray) has gained interest as a potential source of natural and hypoallergenic rubber in Southern Europe. Although, native to northern Mexico, it is suited to semi-arid and Mediterranean environments. A research study was conducted in Sardinia (Italy) to evaluate adaptation and biometric traits of introduced guayule lines and to determine the contents and yields of rubber and resin obtainable from its aboveground biomass. Seedlings of the accessions AZ-1, AZ-2, P803, and 11591 were field transplanted in 2015 at two locations of southern, and northern Sardinia, respectively, differing for annual precipitation. Plant survival rate, height and width, trunk diameter, leaf chlorophyll concentration and photosystem photochemical efficiency were monitored. Shoots were harvested at 30 months after transplanting and were partitioned into twigs and remaining stems and its rubber and resin contents were determined. Location markedly affected plant survival rates and biometric traits. Dry matter yield of aboveground components as well as contents of rubber and resin and plant rubber and resin yields differed significantly among accessions under comparison. We found that AZ1 and 11591 were the most successful accessions at southern Sardinia site, whereas 11591 was the only accession exhibiting a satisfactory plant survival rate in the northern location.

Survival rates of radio-collared female polar bears and their dependent young

1995 ◽  
Vol 73 (7) ◽  
pp. 1312-1322 ◽  
Author(s):  
S. C. Amstrup ◽  
G. M. Durner
Keyword(s):  
Adult Female ◽  
Survival Rates ◽  
Beaufort Sea ◽  
First Year ◽  
Human Populations ◽  
Polar Bears ◽  
Adult Males ◽  
Kaplan Meier ◽  
Second Year ◽  
Sea Survival

Polar bears (Ursus maritimus) are hunted throughout most of their range. In addition to hunting, polar bears of the Beaufort Sea region are exposed to mineral and hydrocarbon extraction and related human activities such as shipping, road building, and seismic testing. As human populations increase and demands for polar bears and other arctic resources escalate, reliable estimates of survivorship of polar bears are needed to predict and manage the impacts of those activities. We used the Kaplan–Meier model to estimate annual survival (with 95% confidence intervals) for radio-collared female polar bears and their dependent young that were followed during a 12-year study in the Alaskan Beaufort Sea. Survival of adult female polar bears was higher than had been previously thought: Ŝ = 0.969 (range 0.952–0.983). If human-caused mortalities were deleted, the computed survival rate was 0.996 (0.990–1.002). Survival of young from den exit to weaning was 0.676 (0.634–0.701). Survival during the second year of life, 0.860 (0.751–0.903), was substantially higher than during the first year, 0.651 (0.610–0.675). Shooting by local hunters accounted for 85% of the documented deaths of adult female polar bears. Conversely, 90% of documented losses of young accompanying radio-collared females were not directly caused by humans. Deaths of dependent young were independent of litter size (P = 0.36), indicating that parental investment in single cubs was not different from investment in litters of two or more. Precise estimates of the survival of independent juveniles and adult males still need to be developed.

scholarly journals Growth Response of Crapemyrtle to Geographical Area and Production Light Level

2007 ◽  
Vol 25 (1) ◽  
pp. 26-32
Author(s):  
K.M. Brooks ◽  
G.J. Keever ◽  
J.E. Altland ◽  
J.L. Sibley
Keyword(s):  
Vegetative Growth ◽  
Growth Response ◽  
Geographical Area ◽  
Geographic Location ◽  
Light Level ◽  
First Year ◽  
Tree Form ◽  
Trunk Diameter ◽  
Second Year

Abstract The effects of geographic location and production light level on vegetative growth and flowering were evaluated as a means of accelerating the development of tree-form crapemyrtles. By the end of the first year of the experiment, Dynamite™, ‘Muskogee’, ‘Natchez’, and ‘Tuscarora’ grown in Oregon were as much as 42, 51, 43, and 92% taller, respectively, than plants in Alabama, while plants generally had less trunk diameter in Oregon. ‘Muskogee’ and ‘Natchez’ in both locations and ‘Tuscarora’ in Alabama were generally taller when grown under 50% shade than plants in full sun, while height of Dynamite™ was not affected by production light level. Trunk diameter of ‘Natchez’ in both locations and of Dynamite™ in Alabama was less when plants were grown under shade, while trunk diameter of ‘Muskogee’ and ‘Tuscarora’ was not affected by production light level. Flowering of plants grown under shade in Alabama was delayed, while no plants in Oregon flowered the first year. In the second year of the experiment when all plants were grown in full sun, all cultivars continued to be taller in Oregon, while trunk diameter remained greater in Alabama. The height advantage gained from growing plants under shade the previous year was not evident in any cultivar by the end of the second year, while trunk diameter was similar for all cultivars previously grown in full sun and under 50% shade. There was no difference in flowering of plants in Alabama previously grown under 50% shade and in full sun, while 50 to 100% of the four cultivars in Oregon flowered with no obvious difference due to prior production light level.

An Unmanned Aircraft System for Automatic Forest Fire Monitoring and Measurement

2011 ◽  
Vol 65 (1-4) ◽  
pp. 533-548 ◽  
Author(s):  
Luis Merino ◽  
Fernando Caballero ◽  
J. Ramiro Martínez-de-Dios ◽  
Iván Maza ◽  
Aníbal Ollero
Keyword(s):  
Forest Fire ◽  
Unmanned Aircraft ◽  
Unmanned Aircraft System ◽  
Fire Monitoring ◽  
Aircraft System ◽  
Monitoring And Measurement

OBSERVATIONS ON THE ORIGIN AND EARLY DEVELOPMENT OF A PLANT COMMUNITY FOLLOWING A FOREST FIRE

1955 ◽  
Vol 31 (2) ◽  
pp. 154-161 ◽  
Author(s):  
J. Lynton Martin
Keyword(s):  
Nova Scotia ◽  
Early Development ◽  
Plant Community ◽  
Forest Fire ◽  
Mineral Soil ◽  
First Year ◽  
Herbaceous Species ◽  
Red Maple ◽  
Shrub Species ◽  
Second Year

The origin of the species on a burned-over area in southwestern Nova Scotia was determined by means of covered plots, and the early stages of succession were followed closely for two years. All of the herbaceous and shrub species which appeared on the area during the first two years were survivors of the fire. Bracken fern showed unquestionable dominance the first year, but its position was severely contested by other herbaceous species and the heath plants during the second year. Seedlings of grey birch and large-toothed aspen appeared the second year and were restricted to patches of bare mineral soil. Sucker growth of red oak, red maple and grey birch was rapid, but it was pruned heavily by deer feeding.

Models for tagging data that allow for incomplete mixing of newly tagged animals

1998 ◽  
Vol 55 (6) ◽  
pp. 1477-1483 ◽  
Author(s):  
John M Hoenig ◽  
Nicholas J Barrowman ◽  
Kenneth H Pollock ◽  
Elizabeth N Brooks ◽  
William S Hearn ◽  
...  
Keyword(s):  
Recovery Rate ◽  
Survival Rates ◽  
Mortality Rates ◽  
Mixing Model ◽  
Natural Mortality ◽  
Fishing Season ◽  
Total Survival ◽  
Incomplete Mixing ◽  
Tag Shedding

The Brownie models for tagging data allow one to estimate age- and year-specific total survival rates as well as tag recovery rate parameters. The latter can provide estimates of exploitation rates if the tag reporting, tag shedding, and tag-induced mortality rates can be estimated. A limitation of the models is that they do not allow for newly tagged animals to have different survival rates than previously tagged animals because of lack of complete mixing. We develop a model that allows for the animals to be incompletely mixed, or not fully recruited, into the population during the entire year in which they are tagged. There is a penalty in terms of precision associated with the use of this model. To increase the precision, we also developed a model for which it is assumed that animals become fully mixed (recruited) after a portion of the year has elapsed. Sometimes, animals must be tagged after the fishing season has begun. In this case, newly tagged animals experience fishing and natural mortality for only a fraction of the year. The partial-year non-mixing model can be modified to account for this situation.

scholarly journals Variability of demographic parameters and population dynamics of Atlantic salmon Salmo salar L. in a south-west French river

2003 ◽  
Vol 60 (2) ◽  
pp. 356-370 ◽  
Author(s):  
J. Dumas ◽  
P. Prouzet
Keyword(s):  
Survival Rate ◽  
Survival Rates ◽  
Maximum Yield ◽  
First Year ◽  
South West ◽  
Salmon Population ◽  
Second Year ◽  
First Year Of Life ◽  
French River ◽  
Good Agreement

Abstract The abundance of the salmon population in the Nivelle River was assessed for 11 cohorts during all the stages of their life cycle, from eggs to spawners. A stochastic life history model was used to simulate the changes in numbers at each stage over several years and to evaluate the parameters of a Ricker-type Stock and Recruitment (S–R) relationship. Parameters necessary for managing the exploitation of the species were also estimated. The results indicated that an average deposition of 611 700 eggs (values varying in a proportion of 1 to 3, depending on the year) produced 4870 0+ parr in autumn (variation from 1 to 5.6); 71.8% of which belonged to the group of future 1-year old smolts. The age 1+ parr were eight times less numerous. Survival from egg to 0+ parr was on average 0.97%, but highly variable (varying from 1 to 15). It was density-dependent and followed Ricker S–R model with an optimum of 7800 parr for a survival rate of 3%. During their second year, the survival of 1+ parr reached 53.4% and varied little. The adult runs of complete cohorts amounted to 196 maiden salmon (range, 88 to 382) and previous spawners comprised only 0.9% of adults. Grilse (1 year in the sea) constituted the majority (88.7%). The overall survival rates from 0+ parr to adult returns (6.2% on average) varied three-fold. The majority was females among the grilse (56.2%) and 2-sea-year salmon (88.6%); all 3-sea-year adults were female. Eggs deposited per female averaged 4200, 8500 and 12 750 eggs in each age group, respectively. Simulations of population abundances at various life stages were in good agreement with the observed data. The S–R relationship revealed the low productivity and the vulnerability of this stock, mainly due to the low survival rate of the young during their first year of life. The maximum yield of 12.2% of recruits could be obtained from a deposition of 1 424 000 eggs, which is twice the present average level.

An evaluation of the success of MOET in two breeds of hill sheep maintained under normal systems of hill flock management

1999 ◽  
Vol 69 (2) ◽  
pp. 367-376 ◽  
Author(s):  
F. Bari ◽  
M. Khalid ◽  
W. Haresign ◽  
B. Merrell ◽  
A. Murray ◽  
...  
Keyword(s):  
Recovery Rate ◽  
Embryo Quality ◽  
Survival Rates ◽  
Negative Relationship ◽  
Embryo Survival ◽  
Factors Affecting ◽  
Embryo Recovery ◽  
Multiple Ovulation ◽  
Middle Range ◽  
The Mean

AbstractThis study was undertaken to investigate factors affecting the success of multiple ovulation and embryo transfer (MOET) in Scottish Blackface (no. = 120) and Welsh Mountain (no. = 120) ewes, over a period of 2 years using a laparoscopic procedure for both embryo recovery and transfer. Superovulation was induced with ovine FSH, with 98 to 100% of ewes of both the breeds responding to the treatment. The overall mean superovulatory responses were 15⋅0 (s.e. 0⋅8) and 12⋅5 (s.e. 0⋅7) for Scottish Blackface and 15⋅3 (s.e. 0⋅9) and 12·8 (s.e. 0⋅8) for Welsh Mountain ewes in years 1 and 2, respectively. However, there was a wide degree of variation in superovulatory responses within each breed, with a range of 3 to 29 in Scottish Blackface and 1 to 40 in Welsh Mountain ewes. The mean embryo recovery rate was 71⋅9 (s.e. 3⋅5) % and 69⋅6 (s.e. 3⋅4) % for Scottish Blackface and 57⋅5 (s.e. 4⋅1) % and 60⋅6 (s.e. 3⋅6) % for Welsh Mountain ewes in years 1 and 2, respectively. The mean number of embryos recovered from Welsh Mountain ewes was significantly (P < 0⋅05) lower than that from Scottish Blackface ewes in both years. The lower mean number of embryos recovered in year 2 for both breeds was entirely a reflexion of the lower superovulatory responses in year 2. A significant (P < 0⋅001) relationship was observed between superovulatory response and the number of embryos recovered for both breeds. Some 77% and 72% of Scottish Blackface ewes and 65% and 73% of Welsh Mountain ewes yielded four or more transferable embryos in years 1 and 2, respectively. Neither the mean number nor the mean percentage of transferable embryos per donor ewe differed between breeds or years. A significant (P < 0⋅001) negative relationship was observed between the time of onset of oestrus and both superovulatory response and number of embryos recovered in Scottish Blackface ewes only. Embryo quality was affected by the time of onset of oestrus. In both breeds, the highest proportion of grade 1+2 embryos and the lowest proportion of unfertilized/degenerate embryos occurred in the middle range time, with a reduction in the proportion of grade 1+2 embryos in ewes that came into oestrus either early <19 h) or late (>30 h) after sponge removal. Only one embryo was transferred to each recipient and the embryo survival rates were 76⋅8% and 74⋅6% (Scottish Blackface), and 69⋅6% and 87⋅3% (Welsh Mountain) for years 1 and 2, respectively. Overall the results of this study suggest that MOET is as successful in hill ewes as has been reported for lowland breeds, even without making any major concessions to their hill status.

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