Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 166

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Increment of growing stock is one of the key indicators useful in forest management. In the State Forests in Poland, up to now it is estimated using growth and yield tables elaborated a century ago. Paper presents results of study concerning current annual increment of Scots pine stands. Basing on repeated measurements of stand volume increment was estimated to 14.5 m3/ha for stands in age from 37 to 60 years and to 6.2 m3/ha for stands aged over 140. Increment estimated by measurements was 30−80% higher than increment evaluated using growth and yield tables for particular age classes.
Sustainable forest management, the leading topic in forest and environmental policy since the 1990s, has required an appropriate tools for both clarification of general principles and measurement of its progress. Many of indicators developed for these purpose are based on forest area. However, definitions of forest are not compatible, especially on national and worldwide scale. Definition of forest applied by FAO refers to crown cover and land use, while definition adopted for reporting under Kyoto Protocol refers only to the occurrence of trees. Polish Act on Forest applies the destination of land use as a determinant of forest. Paper analyses the process of forest area assessment in Poland for the purpose of national as well as FAO and UNFCCC reporting. Natural expansion of trees on abandoned agriculture land, still classified as the agriculture areas in cadastral system, was recognized as the biggest challenge of forest area assessment in Poland. Although natural succession is described by many authors, the total area subjected to this process is unknown. According to the FAO and Kyoto Protocol rules such areas should be reported as forests. As a consequence, forest area in Poland could be at least a few hundred thousand hectares higher than reported in the last assessments basing only on cadastral system. The proper classification of forests not recorded in the cadastral system would also be important challenge, otherwise between forest area on country and international level will be a huge discrepancy. But, there are some areas classified as a forest in Poland, which probably should not be included within FAO and Kyoto reporting. However, the most important topic concerns the possibility of identification of afforested areas, submitted under article 3.3. of Kyoto Protocol, basing on forest area changes between 1989 and 2012. One should recognise if afforested area is not overestimated using such approach, as a result of modification of forest definition in Poland in 1991. Additional question concerns the forest lands included into cadastral system after 1990, but afforested or resulting from natural succession occurring before that time, which currently are reported as afforestation under article 3.3. of Kyoto Protocol.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.