1.02.07 - Ecology and silviculture of subtropical forests
Unit 1.02.07
Xiongqing Zhang, China
Sophan Chhin, United States
About Unit
The Working Party "Ecology and Silviculture of subtropical forests" explores the structure and function of subtropical forest ecosystems and the impact of management activities and climate change, aiming to find out and provide the better ways to restore, manage and improve subtropical forests. The unit encourages the forest scientists to promote the international cooperation in scientific studies embracing the whole field of research related to ecology and silviculture of subtropical forests.
State of Knowledge
Subtropical forests located to the two belts between the tropics (+/- 23.4o) and nearly 30o north and south of the equator, which have usually been viewed as a transition between the tropical forests and the temperate forests by biologists (Corlett, 2013). Because of the descending branches of the Hadley circulation (the subtropical high), much of the subtropical regions are too dry (mean annual rainfall < 600-700 mm) for forests.
Subtropical forests are distributed on the southeastern side of all the continents, particularly in China and adjacent countries (occupied about 71% of the subtropical forest area), and in northern Argentina and southeastern Brazil (23%), with smaller areas in northern Mexico and the southeast USA (4%), eastern Australia (2%), and southern Africa (1%) and a very small area in southeastern Madagascar (Corlett and Hughes, 2015).
Except in monsoon Asia, long-term drying has limited the subtropical area, and human activities have also reduced their area in those regions with suitable climates. Because of the climate in subtropics, much of the extant subtropical forest is secondary, degraded, or consists of plantations. These forests are vulnerable to cyclones and ice-storms. In early 2008, an unprecedented ice storm caused massive mechanical damage of subtropical forests in China, and the damage degree for the typical forest types ranged from 25% to 66% (Zhou et al., 2011).
However, these forests in subtropics have received much less attention than those in the tropics, in spite of their importance for both biodiversity and carbon sequestration. Their relatively small area reduces the global significance of subtropical forests for carbon sequestration, but some have both a high biomass and a high sink capacity per area. The importance of scientific findings of subtropical forest ecosystems and forest practices that contribute to the sustainable management of subtropical forests is increasing.