ORGANIC PRODUCTION, TURNOVER AND MINERAL CYCLING IN WOODLANDS

• Published in: Biological Reviews
• Main Author: OVINGTON, J. D.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1965
• Subjects: taiga
• Online Access: http://dx.doi.org/10.1111/j.1469-185x.1965.tb00805.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1469-185X.1965.tb00805.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-185X.1965.tb00805.x

Summary 1. A distinction is made between the production of tree trunks (economic) and the production of all kinds of primary organic matter (biological) by woodland plants capable of photosynthesis. 2. Yield tables, quality class and site index are considered to be reasonably satisfactory indicators of trunk wood production, but their value as indicators of biological production has not been demonstrated. 3. Some factors, namely geographical, weather, edaphic, genetical, management and biotic, are considered in relation to their influence on economic production. 4. Attention is drawn to the relative paucity of data on biological production. 5. The available information of woodland biomass suggests that the greatest biomass of the world's forests exceeds 500 times 10 3 kg. of oven‐dry material per hectare. 6. The annual accumulation of plant material in woodland ecosystems can be very rapid, up to about 20 kg./ha. when growth is active. The bulk of the organic matter is in tree trunks but where decomposition is slow large amounts of organic matter are present as litter on the forest floor. 7. Biomass change is considered an unsuitable measure of biological production since it is affected greatly by tree harvesting. 8. Net primary production is regarded as a better measure of biological production. Some of the more serious sources of error in determining net primary production are emphasized. Generally net primary production is underestimated because of failure to take into account the removal of photosynthate by animals and because of infrequent sampling so that the production of plant parts such as inflorescences is missed. 9. Woodlands are shown to be one of the most productive terrestrial communities, giving a range of annual production as 10 3 kg./ha., from 5 for fir forests of the northern taiga in the U.S.S.R. to 33 in tropical rain forests. The capacity of forests to produce large amounts of organic matter annually is attributed to the large root and leaf mass which permit relatively full use to be made of ...