Variations de la régénération préétablie dans les sapinières boréales en fonction de leurs caractéristiques écologiques

1991 ◽  
Vol 21 (12) ◽  
pp. 1779-1795 ◽  
Author(s):  
Sylvie Côté ◽  
Louis Bélanger
Keyword(s):  
Balsam Fir ◽  
Site Conditions ◽  
Analysis Method ◽  
White Birch ◽  
Ecological Site ◽  
Advanced Regeneration ◽  
Second Growth ◽  
Cluster Analysis Method ◽  
Very High ◽  
Three Phases

The renewal of boreal fir stands after harvesting is related to the abundance of fir advanced regeneration. The objective of this study was to compare the advanced regeneration in 45-years-old balsam fir stands of second growth to determine if ecological site conditions could explain some regeneration problems noted in the balsam fir – white birch ecoclimatic domain. Seven ecological phases were studied; these are among the most common in the Laurentians north of Québec. On the basis of fir seedling densities (2 years old and more), three groups could be distinguished using a cluster analysis method for grouping means. Dry balsam fir – herb-and-moss type on well drained tills formed a first group characterized with very high seedling densities (> 60 000 seedlings/ha). A second group, characterized with high seedling densities (25 000 – 40 000 seedlings/ha), was constituted of three phases with an important moss cover:the mesic balsam fir – moss-and-herb type on moderately well drained tills, the humid balsam fir – moss-and-herb type on imperfectly drained tills with seepage, and the humid balsam fir – moss type on imperfectly drained tills. A third group, with low seedling densities (< 15 000 seedlings/ha), included three phases recognized by their important herb cover associated with a less abundant moss cover: the dry balsam fir – herb type on well drained till, the mesic balsam fir – white birch – herb type on moderately well drained till, and the mesic rich balsam fir – herb type on moderately well drained tills with seepage. Low densities of fir advanced regeneration seemed to be related to the abundance of leaf litter on the forest floor that could hinder fir regeneration. Insufficient natural coniferous regeneration can be anticipated in this last group if harvesting follows the 45-year rotation currently used now in Quebec.

Croissance de sapinières à bouleau blanc boréales issues de coupe avec protection de la régénération

1992 ◽  
Vol 22 (11) ◽  
pp. 1701-1711 ◽  
Author(s):  
Lucie Bertrand ◽  
Louis Bélanger ◽  
Robert L. Beauregard
Keyword(s):  
Natural Regeneration ◽  
Basal Area ◽  
Balsam Fir ◽  
Growth And Yield ◽  
Permanent Plots ◽  
White Birch ◽  
Second Growth ◽  
Harvesting Method ◽  
Volume Production ◽  
Rotation Age

Models of compatible volume and basal area growth and yield covering a period of 10 to 45 years after harvesting were developed for second growth boreal stands of balsam fir (Abiesbalsamea (L.) Mill.). The 131 permanent plots used for the study were located near Matane, in the Gaspé Peninsula, and are part of the balsam fir–white birch ecoclimatic domain. These stands were harvested in 1934, 1944, and 1953, using a manual cut-and-bunch harvesting method that protected advance growth, and measures were taken in 1954, 1964, and 1978. The stands were moderately affected by spruce budworm outbreaks between 1950–1957 and 1975–1978. Years elapsed since release rather than total age was used as the temporal variable. Even though the characteristics of the coniferous natural regeneration were quite variable, total basal area explained an important part of growth variations of young fir stands by integrating both density and dimensions of the regeneration. Results show, within the limits of the observed densities (< 15 000 stems/ha, 10 years after harvesting), that stands with a higher basal area will have higher total and merchantable volumes at a given age; rotation age for maximum volume production will decrease correspondingly. Abundance of saplings in the initial natural regeneration can thus have an important impact on stand production and rotation age. In the case of nonoverdense young fir stands (< 15 000 stems/ha, 10 years after harvesting with no height growth impediment), the use of spacing treatments that significantly reduce total basal area could be questioned when pursuing maximum fiber production.

A reexamination of moose damage to balsam fir–white birch forests in central Newfoundland: 27 years later

1993 ◽  
Vol 23 (7) ◽  
pp. 1388-1395 ◽  
Author(s):  
Ian D. Thompson ◽  
William J. Curran
Keyword(s):  
Species Composition ◽  
Forest Canopy ◽  
Black Spruce ◽  
Positive Influence ◽  
Forest Growth ◽  
Balsam Fir ◽  
Isle Royale ◽  
White Birch ◽  
Second Growth ◽  
The Mean

A 1960 study from central Newfoundland suggested that moose (Alcesalces L.) would: (i) reduce the commercial value of second-growth forests of central Newfoundland by excessive damage to balsam fir (Abiesbalsamea (L.) Mill.); (ii) eliminate white birch (Betulapapyrifera Marsh.) from the forest canopy; (iii) alter conifer species composition; and (iv) reduce the carrying capacity of the area for moose. We resurveyed the original study areas in 1987. Our data suggest that moose have altered species composition in favour of white spruce (Piceaglauca (Moench) Voss) and black spruce (Piceamariana (Mill.) B.S.P.) on some sites and have reduced the mean height of balsam fir trees. White birch was generally absent from the canopy. However, contrary to the 1960 prediction, moose appear to have had a positive influence on forest growth by thinning most areas to stem densities comparable with those of precommercially thinned stands. Data from this study were compared with a general model of the influence of moose on balsam fir forests developed for Isle Royale, Michigan. Our data supported two predictions from Isle Royale: moose damage was highest at low balsam fir densities and at highest moose densities. Our results contradicted a third prediction, that height growth was greater in high density stands of saplings. Also, unlike at Isle Royale, despite heavy browsing pressure for extended periods, balsam fir will continue to dominate central Newfoundland forests.

Relationships between balsam fir vulnerability to spruce budworm and ecological site conditions of fir stands in central Quebec

1991 ◽  
Vol 21 (12) ◽  
pp. 1752-1759 ◽  
Author(s):  
Alain Dupont ◽  
Louis Bélanger ◽  
Jean Bousquet
Keyword(s):  
Regional Differences ◽  
General Pattern ◽  
Spruce Budworm ◽  
Moisture Gradient ◽  
Intermediate Level ◽  
Balsam Fir ◽  
Moisture Regime ◽  
Site Conditions ◽  
Ecological Site ◽  
Site Type

A clear relationship (P < 0.05) was found between ecological site conditions of fir stands approaching maturity and mortality of balsam fir (Abiesbalsamea (L.) Mill.) caused by the last spruce budworm (Choristoneurafumiferana (Clem.)) outbreak. This relationship was observed in three ecoclimatic regions in central Quebec. Generally, in areas moderately affected by the outbreak, three levels of mortality could be identified following four moisture regime classes: xeric fir stands [Formula: see text] and hydric fir stands [Formula: see text] were the most vulnerable, mesic fir stands showed an intermediate level of mortality [Formula: see text], while subhygric fir stands with seepage were constantly less vulnerable [Formula: see text]. This general pattern of mortality was observed in the three ecoregions surveyed, in spite of important regional differences (climate, intensity of the outbreak, stand composition) among them. Except for the mesic sites, levels of mortality for the same site type did not vary significantly (P > 0.05) from one ecoregion to another. The effect of moisture gradient on stand vigor and the biological performances of the spruce budworm may explain the results obtained.

scholarly journals Detection of drought events in Greece using daily precipitation

2010 ◽  
Vol 41 (2) ◽  
pp. 126-133 ◽  
Author(s):  
N. Kalamaras ◽  
H. Michalopoulou ◽  
H. R. Byun
Keyword(s):  
Cluster Analysis ◽  
Hierarchical Cluster Analysis ◽  
Daily Precipitation ◽  
Hierarchical Cluster ◽  
Seasonal Distribution ◽  
Drought Severity ◽  
Severe Drought ◽  
Analysis Method ◽  
Cluster Analysis Method ◽  
Insight Into

In this study a method proposed by Byun & Wilhite, which estimates drought severity and duration using daily precipitation values, is applied to data from stations at different locations in Greece. Subsequently, a series of indices is calculated to facilitate the detection of drought events at these sites. The results provide insight into the trend of drought severity in the region. In addition, the seasonal distribution of days with moderate and severe drought is examined. Finally, the Hierarchical Cluster Analysis method is used to identify sites with similar drought features.

scholarly journals ANALISIS KINERJA KEUANGAN PADA DINAS BINA MARGA DAN SUMBER DAYA AIR KABUPATEN BANJAR

2017 ◽  
Vol 3 (2) ◽  
Author(s):  
Fariz Syahidi
Keyword(s):  
Financial Management ◽  
Capital Expenditure ◽  
Infrastructure Development ◽  
Analysis Method ◽  
Efficiency Ratio ◽  
Average Performance ◽  
Performance Targets ◽  
Capital Spending ◽  
Operational Expenditure ◽  
Very High

Abstract: The purpose of this study was to determine the effectiveness, efficiency and growth on Highways and Water Resources Office of Banjar regency. The data analysis method was descriptive quantitative. The results showed that the average performance of the financial management of the efficiency ratio in 2013, 2014, 2015 was not efficient, due to the lack of savings in indirect expenditures or the payment of salaries of civil servants. Meanwhile, the effectiveness ratio in 2014 and 2015 were effective but in 2013 was quite effective. The effectiveness achievement was based on employees’ performance to realize performance targets and financial targets. The growth of revenue, capital expenditure and operational expenditure showed high to very high results. It means that the development growth increased every year, especially in capital spending as a means to financed infrastructure development for roads, bridges and maintenance. Keywords: efficiency, effectiveness, growth Abstrak: Tujuan penelitian ini adalah untuk mengetahui nilai efektifitas, efisiensi dan pertumbuhan pada Dinas Bina Marga dan Sumber Daya Air Kabupaten Ban-jar. Metode analisis data dalam penelitian ini adalah kuantitatif deskriptif. Hasil penelitian menunjukkan bahwa rata-rata kinerja pengelolaan keuangan pada rasio efisiensi tahun 2013, 2014 dan 2015 tidak efisien. Hal ini dikarenakan tidak adanya penghematan pada belanja tidak langsung atau pembayaran gaji PNS. Pa-da rasio efektifitas tahun 2014 dan 2015 efektivitas dan tahun 2013 cukup efekti-vitas. Pencapaian hasil efektifitas didasarkan pada hasil kinerja pegawai yang mampu merealisasikan target kinerja dan target keuangan. Pertumbuhan PAD, be-lanja modal dan belanja operasional menunjukan hasil yang tinggi hingga sangat tinggi. Hal ini berarti dari tahun ke tahun pertumbuhan pembangunan mengalami peningkatan terutama pada belanja modal sebagai sarana untuk pembiayaan pem-bangunan infrastruktur pembangunan jalan, jembatan dan pemeliharaannya..Keywords: efisiensi, efektifitas, pertumbuhan

scholarly journals Is hidrorium able to improve the students’ critical thinking skills?

2020 ◽  
Vol 8 (1) ◽  
pp. 20-28
Author(s):  
Dedy Dwi Setyawan ◽  
Ali Mustadi
Keyword(s):  
Critical Thinking ◽  
Thinking Skills ◽  
Critical Thinking Skills ◽  
Analysis Method ◽  
Test Items ◽  
High Category ◽  
Test Instrument ◽  
The Media ◽  
Very High ◽  
Passing Grade

The condition of the students’ critical thinking skills in the Kowangbinangun State Elementary School has impacted their learning results. Departing from this situation, a study for improving the students’ critical thinking skills and learning results by using hidrorium as the media should be conducted. Within the conduct of the study, the approach that had been adopted was the classroom action research. Then, the instruments that had been implemented were the test instrument, namely the test items for measuring the achievement of the students’ learning results, and the non-test instrument, namely the assignment assessment rubric for measuring the students’ critical thinking skills level. Furthermore, the data analysis method that had been adopted was the descriptive-comparativee method. Within the first cycle, 4% of the students belonged to the “Very High” category, 14% of the students belonged to the “High” category, and 82% of the students belonged to the “Low” category; as a result, 33% of the students met the passing grade while 67% of the students did not meet the passing grade. The research in the first cycle improved the students’ critical thinking skills and thus 14% of the students belonged to the “Very High” category, 57% of the students belonged to the “High” category, and 29% of the students belonged to the “Low” category. Following up the improvement, the learning results of the students showed that 64% of the students met the passing grade whereas 36% of the students did not meet the passing grade. In the second cycle, the students’ critical thinking skills also improved since 86% of the students belonged to the “Very High” category and 14% of the students belonged to the “High” category. Thus, the students’ learning results improved as well with 82% of the students met the passing grade and 18% of the students did not meet the passing grade.

Cluster Analysis Using N-gram Statistics for Daihinmin Programs and Performance Evaluations

2016 ◽  
Vol 4 (2) ◽  
pp. 33-57 ◽  
Author(s):  
Seiya Okubo ◽  
Takaaki Ayabe ◽  
Tetsuro Nishino
Keyword(s):  
Cluster Analysis ◽  
Imperfect Information ◽  
Computer Game ◽  
Computer Experiments ◽  
Performance Evaluations ◽  
Analysis Method ◽  
Cluster Analysis Method ◽  
N Gram ◽  
And Performance ◽  
Feature Values

In this paper, the authors elucidate the characteristics of the computer game Daihinmin, a popular Japanese card game that uses imperfect information. They first propose a method to extract feature values using n-gram statistics and a cluster analysis method that employs feature values. By representing the program card hands as several symbols, and the order of hands as simplified symbol strings, they obtain data that is suitable for feature extraction. The authors then evaluate the effectiveness of the proposed method through computer experiments. In these experiments, they apply their method to ten programs that were used in the UEC Computer Daihinmin Convention. In addition, the authors evaluate the robustness of the proposed method and apply it to recent programs. Finally, they show that their proposed method can successfully cluster Daihinmin programs with high probability.

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