Articles containing the keyword 'age class'
Category : Article
The data has been collected from an old natural meadow in Sortavala, Karelia (on that time it was part of Finland). The vegetation on that meadow was very homogenous. All plants of the selected species (Trollius europaeus; Ranunculus auricomus; R. acer; Potentilla erecta; Alchemilla vulgaris; Geum rivale; Prunella vulgaris; Chrysanthemum leucanthemum; Polygonum viviparum) were collected from the sample plots with their roots. The seedlings were then ordered into age classes, and the shortest possible time before inflorescence was determined. To find out the germination time sowing trials were conducted.
The seedlings are very abundant in the youngest age classes and then the amount of plant individuals sinks quickly. The reasons for dying are e.g. insufficient amount of nutrients available and the lack of winter hardiness.
The PDF contains a summary in Finnish.
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Linkola,
E-mail:
kl@mm.unknown
The data has been collected from northern Finland between about 64th and 68th north latitudes, excluding the polar tree line areas. The sample plots have been selected to represents greatest variation of the habitats in altitude, rainfall and other site factors. The selected trees were cut, their age, height, and diameter at various heights examined and possible signs of forest fires noticed. The age of the trees was examined also with microscope. The age class distribution of the sample plots was studied. The determination of historical seed years was based on age class distribution of the sample plots.
Grouping of the trees into different age classes was too weak a method to make any conclusions about the periodicity or even less about the frequency of the seed years. There were also noticeable differences in determining the age of the trees between macroscopic and microscopic age examination. There are also differences in the amount of seedlings between different forest types.
The growth of pines in northern Finland is very slow particularly in the young ages but the growth increases after they reach 1,3 meters, which may take up to 30 years. The development of the forest has been similar through last centuries-
Lakari,
E-mail:
ol@mm.unknown
The data used to control the developed methods are presented in chapter two. The third chapter presents the statistical analysis conducted. The factor analysis shows that tree stand characteristics must be divided into three factors to able the information needed for site indexing to distinguish different site classes. The phases of model development are presented and the results of calculations with control data are shown.
The results indicate that for calculations of nature-normal forests the suitable amount of tree stand characters for creating the site indexing function, is three. These are: number of trees (N), basal area of the stand (G) and mean height (H).
The PDF contains a summary in Finnish.
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Kangas,
E-mail:
yk@mm.unknown
The article is the first part of a wider project aiming to study the measurement practices of stand’s height-over-age based classifications and to develop new methods for actually measuring the side index.
The first part of the article presents the concepts of site indexing and discusses it with a mathematical model. The second part of the article examines the structure of site indexing system regarding the reliability of the method. Third part presents the factors affecting the method development and the fourth part discusses the possible site index classes and their characteristics.
The PDF contains a summary in Finnish.
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Kangas,
E-mail:
yk@mm.unknown
Category : Research article
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Sariyildiz,
Kars Kafkas Üniversitesi, Artvin Orman Fakültesi, 08000 Artvin, Turkey
E-mail:
t_sariyildiz@yahoo.com
- Anderson, Department of Biological Sciences, Hatherly Laboratories, University of Exeter, Exeter EX4 4PS, UK E-mail: jma@nn.uk
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Kuboyama,
Forestry and Forest Products Research Institute Tohoku Center, Nabeyashiki 72, Shimo-Kuriyagawa, Morioka, Iwate, 020-0123 Japan
E-mail:
kuboyama@ffpri-thk.affrc.go.jp
- Oka, Forestry and Forest Products Research Institute Tohoku Center, Nabeyashiki 72, Shimo-Kuriyagawa, Morioka, Iwate, 020-0123 Japan E-mail: ho@nn.jp
