Optimal forest management for carbon sequestration and biodiversity maintenance : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Economics at Massey University, Turitea, New Zealand
Managing planted forests for carbon sequestration and biodiversity maintenance
has become increasingly important in times of rapid climate change and the loss
of biodiversity worldwide. The objectives of this study are to find out private and
socially optimal management strategies for planted forests, and suggest an
appropriate policy for promoting multiple-use forests.
The research attempts: (1) to identify the harvesting strategies of forest stands that
can maximise the benefits from timber production and carbon sequestration; (2) to
identify the patterns that can balance economic gain and biodiversity
maintenance; (3) to examine the actual management strategies and biodiversity
conservation attitudes of forest owners; and (4) to recommend policy tools that
can be used to align private with socially optimal decisions.
The Faustmann model is extended to include carbon sequestration, biodiversity
conservation, multiple forest stands and spatial arrangements among forest stands.
The Safe Minimum Standard Approach is employed to model biodiversity
conservation. The number of birds is used as a biodiversity indicator. A direct
search algorithm is used to determine optimal sets of harvesting strategies. The
models are applied to planted forests in Yen Bai province, Vietnam. To get
primary data, 291 household forest owners and 4 state enterprises, growing
Eucalyptus urophylla and Acacia mangium were surveyed.
The results show that the actual cutting ages are 5 and 7 years for household and
enterprise forests, respectively. Both the optimal timber and carbon rotation ages
are between 9 and 11 years for two species. The value of carbon uptake makes the
optimal rotation age slightly shorter. The incorporation of spatial arrangements
has little impact on the optimal rotation age, but significantly increases the net
present value. The inclusion of biodiversity conservation lengthens the rotation
age and significantly reduces the profitability of forest owners. Policy
implications are that payment for carbon sequestration services of planted forests
in Vietnam is feasible. Merging small forest stands of several forest households
should be encouraged. Direct payments are an appropriate policy tool to
encourage household forest owners to lengthen rotation ages in order to enhance