Determination of the best canopy gap area on the basis of soil characteristics using the Analytical Hierarchy Process (AHP)

Autorzy

• Yahya Kooch Tarbiat Modares University, 46417-76489, Noor, Mazandaran, Iran,
  phone: +98-122-6253101 (-3), fax: +98-122-6253499
• Seyed Mohsen Hosseini Tarbiat Modares University, Faculty of Natural Resources, Department of Forestry, P.O. Box 14115-111, Tehran, Iran
  phone: 09111213898, fax: 01226253499, e-mail: hosseini@modares.ac.ir
• Jahangard Mohammadi Shahrekord University of Medical Sciences, Teheran, Iran
• Seyed Mohammad Hojjati Sari Agricultural Sciences and Natural Resources University Sari
  Mazandaran, Iran

Abstract

The assessment of canopy gap areas on the basis of soil characteristics in forest ecosystems could be one of benefit points for management of forests. This research was conducted in 20 ha areas of Experimental Forest Station of Tarbiat Modares University that is located in a temperate forest of Mazandaran province in the north of Iran. Twenty one canopy gaps with different areas were found in studied areas and classified as small (85.12 m²), medium (325.21 m²), large (512.11 m²) and very large (723.85 m²) gaps. These areas classes of canopy gaps were assessed with respect to nine criteria (soil pH, carbon to nitrogen ratio, cation exchange capacity, phosphorus, potassium, calcium, nitrogen mineralization, microbial respiration and earthworm’s biomass). Soil samples (0– 45 cm depth from the gap center and edge positions) were measured in the laboratory. The Analytical Hierarchy Process (AHP) was used for assessment of canopy gap areas. This method is widely used the Multiple Criteria Decision Support (MCDS) method and perhaps the most popular in many fields, including natural resource management, especially in forest sciences. Results of AHP indicate that the maximum of local priority belongs to small areas of canopy gaps when considering all soil characteristics. However, medium, large and very large canopy gap areas have priorities, respectively. The calculated overall priority showed that with respect to considered criterias, small and medium gap areas have higher, more ideal condition in comparison to large and very large areas. AHP results emphasise that considering soil characteristics canopy gap areas should be less than 400 m² in Hyrcanian forests of Iran. Also, AHP can be introduced as an effective instrument in decision-making processes for investment planning and prioritization in compliance with environmental regulations.

Keywords

• soil characteristics
• Hyrcanian forest
• Iran
• canopy gap
• beech