Biological processes as indicators of sustainable plantation forestry
This paper discusses the use of an ecosystems approach in the management of plantations and the concept of plantations in providing goods and services. Ecological indicators are compared for the CIFOR and South African systems. The CIFOR system focuses on three criteria, which involve the maintenance of a) biodiversity, b) ecosystem function and c) genetic variation. The South African system has chosen six criteria: a) the protection of natural forests, b) conservation of biodiversity, c) conservation of ecosystem structures and processes, d) protection of forests from fire, pests, diseases and alien plants, d) maintenance of production potential and e) the conservation of soil and water resources. Ideas are presented on indicators and measures, which may be useful in the sustainable management of nutrient cycling, yield production, pest outbreaks and water use and quality. Indices of nitrogen mineralization rates, soil carbon stocks and ongoing mensuration of biomass are key measurements. Under global change conditions it is predicted that the outbreaks of pests will be more severe and the industry must be prepared to invest in appropriate monitoring and technologies. It is emphasized that a framework needs to be provided into which the indicator measures can be placed. This would best be accomplished by the simultaneous development of a number of relatively simple ecosystem and plant-physiological based models.