Browsing by Subject "inventory for rare forest phenomena"

Coarse woody debris (CWD) is an important indicator of biodiversity in forests, the source of organic material and carbon dioxide in the atmosphere and the habitat for a wide variety of organisms. In southern Finland, the amount of CWD per hectare in fresh mineral soils of old spruce-dominant forests can be as much as 90–120 m3 ha-1. In managed forests, however, it is only about 2–10 m3 ha-1, due to the management methods used in forests. The spatial pattern of CWD in managed forests is an essential research area, although it has rarely been studied. With knowledge of the spatial pattern of CWD in managed forests, it is possible to investigate inventory methods of rare phenomena, such as adaptive cluster sampling or line intersect sampling. The field measurements were performed in eastern Finland as part of one of the most extensive projects in Finland to inventory rare phenomena. Altogether 340 hectares of managed forest were inventoried by strip survey and over 11 600 dead trees were measured. The spatial pattern of CWD was examined with Ripley’s K –method. The method allows spatial assessment at different scales among and between species and enables one to determine how CWD is located in the study area used. The results of this study indicate that the CWD is located clustered in the area level in every spatial scale below 25 m. The spatial pattern of the CWD was complete random in approximately 63% of the forest management compartments in every studied spatial scale. The spatial pattern was clustered in 12% of the compartments. The spatial pattern was a mixture of random and clustered pattern in the rest (25%) of the compartments. In the future, the results of the study will be used as background information for examining inventory methods of rare phenomena and damages in managed forests.