Сводный каталог книг

[Текст] / P.E. Vezina ; Canada Department of Forestry. - Ottawa : Canada Department of Forestry, Forest Research Branch, 1964. - 474-481 с. + table. - (Forest Research Branch Contribution / Canada Department of Forestry ; 620). - Библиогр: p. 481. - 0-05 р.

УДК

634.9T

Аннотация: The concept of stand density is fundamental in forestry. Investigations of problems of mensuration, growth and yield, and silviculture need to consider density as one of the main stand variables. Several methods of expressing density were defined and discussed in an earlier study (Vezina 1963a). This paper discusses the results obtained in testing some common methods of expressing stand density in relation to crown closure of both balsam fir (Abies balsamea (L.) Mill.) and jack pine (Pinus banksiana Lamb.). stands in Quebec. A more general objective was to discuss the development of the stand density concept: how it developed in the past and how one may expect it to develop in the future.

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[Текст] / P.E. Vezina. - Quebec City : Department of Forestry, Laval University, 1965. - 752-755 с. : figure. - Библиогр: p. 754. - 0-20 р.

УДК

631.4

Аннотация: Seasonal fluctuations of humus pH of three commonly occurring forest soils in Quebec were assessed to determine which of four different methods was best suited for comparisons of pH among sites. Seasonal variations of 1.1 to 1.3 units were observed on all soil types tested. Humus pH was highest in midsummer and decreased as winter approached. Different pH values were obtained from the same time by the different methods used. Reproducibility of pH measurements is briefly discussed.

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