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    Wyświetlanie 1-2 z 2
    Tytuł:
    Wpływ typu siedliskowego lasu na przychody uzyskiwane w ramach wczesnych i późnych trzebieży pozytywnych
    Influence of the forest habitat type on the income from the early and late positive thinnings
    Autorzy:
    Gostołek, R.
    Rutkowska, A.
    Adamowicz, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/986630.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    gospodarka lesna
    typy siedliskowe lasu
    trzebieze
    trzebiez pozytywna
    trzebiez wczesna
    trzebiez pozna
    przychody
    sprzedaz drewna
    thinnings for positive selection
    income
    forest economics
    Opis:
    Environment creating and general social cost−consuming factors are of the utmost importance to realize the multifunctional forest management. As a result, in some forest districts, one notes a disproportionate relationship between the costs and incomes. It can determine the level of the achieved profitability and influence the availability of the financial resources. One of the crucial elements of the realization of the forest management is the constant control of the cash flow (income and costs). Because of the specification of the forest management, the flows are determined by the economic as well as ecological factors. This is the reason of exploring of the influence of forest habitat types on the sales income reached as part of the early and late thinning for positive selection. The income from the sales of 100,798 m3 woody raw material acquired from 3,628 ha was analyzed. Forest habitat type significantly influenced the income taken from the sale of woody raw material that was reached as the part of analyzed tending (V=44%). It was proved that forest habitat type in case of early thinning for positive selection had higher all−important influence on the income acquired from the sale of wood than in case of late thinning for positive selection, which was determined as the middle influence (V=56 and 24%, respectively).
    Źródło:
    Sylwan; 2018, 162, 03; 179-188
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Trzebieże wczesne w Lasach Państwowych w Polsce – rozwój czy regres?
    Early thinnings in the State Forests in Poland – development or regress?
    Autorzy:
    Łukaszewicz, J.
    Zajączkowski, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/980288.pdf
    Data publikacji:
    2019
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    Panstwowe Gospodarstwo Lesne Lasy Panstwowe
    hodowla lasu
    lasy panstwowe
    zabiegi pielegnacyjne
    trzebiez wczesna
    drzewa lesne
    selekcja pozytywna
    drzewa przyszlosciowe
    stand tending operation
    principles of silviculture
    positive selection
    future trees
    stand stability
    Opis:
    Early thinning operations performed in relatively young stands, the most important element of the forest ecosystem, have a much greater impact on their stability than late thinning performed in the stands of older age classes. As regards early thinning, the method of tending cuts based on positive selection (selection and promotion of superior trees) developed by Ilmurzynski has formally been operating in the Polish ‘Principles of silviculture’ and forest practice in the State Forests since 1961. The paper analyses changes in the provisions of subsequent editions of the ‘Principles of silviculture’ (from 1953 to 2012) concerning early thinning operations and their implementation into forest practice in the stands managed by the State Forests. A gradual departure from the superior tree selection method as well as properly performed positive selection is observed. These changes could already be found in 1979. The lack of consistency in determining the aim of thinning treatments makes each of them a separate part of the operation. Because of the lack of consistent selection and promotion of specific trees, the conditions for positive selection are not met. The current ‘Principles of silviculture’ [2012] operating in the State Forests do not recommend the consistent selection of superior trees, but advise early thinning treatments based on the principle of negative selection corresponding to weak upper thinning (grade D according to method of the Association of German Forest Experimental Station from 1902). However in the practice, early thinning treatments similar to moderate lower thinning are often carried out instead (grade B according to method of the Association of German Forest Experimental Station from 1902). Such recommendations and operations regarding early thinning are the main cause of the lack of stability and resistance of stands to the impact of abiotic and biotic factors contributing to reducing the productivity of the forest. We consider it necessary to introduce modifications depending on the use of elements of the future tree method (reduction of the number of superior trees per ha) and group thinning (selection and permanent identification of the groups of superior trees). We propose the following number of superior trees per ha selected during the first early thinning operation: 200−300 for pine, 250−400 for spruce, 100−200 for oak, and 150−200 for beech. The current dissonance between the operating provisions and their arbitrary implementation into forest practice does not increase the silvicultural quality resulting from thinning treatments, which translates into the stability and productivity of stands. To prevent such a situation, we recommend conducting a series of regular training courses for forest staff on permanent thinning sample plots in all forest districts.
    Źródło:
    Sylwan; 2019, 163, 01; 13-24
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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