To conduct proper simulations for ozone, PM2.5, and fire smoke, it is necessary to understand the species composition and leaf mass for California flora. Yet, leaf mass quantification and plant species composition and dominance may be the weaker links in the development of biogenic emissions estimates, both for plants in urban settings and for emission inventories at a regional level. Of particular interest in this regard are California native oaks, because of their high emission rates, large area extent, and large masses of foliage. For California airsheds, the development of the GAP land cover database in principle offers plant species-specific data useful for BVOC emission inventories. However, although GAP is arguably the most recent and comprehensive land cover database available, it has been developed for other purposes, especially for identifying habitats of threatened plant or animal species, and thus may lack the degree of quantification needed for biogenic emissions inventory development.
Moreover, the translation of land cover data such as GAP to emissions models is problematic because a dimension of leaf mass must be added to the existing data, or a relationship must be derived between data from remote sensing and foliar masses.
Through a ground-truth approach in a series of ARB-sponsored studies, our group has generated experimental data with which to evaluate the GAP database and to test leaf mass and leaf area estimation methodologies for urban trees, California native oaks, and plants in natural communities. Continuation of leaf mass assessments in conjunction with evaluation and development of new
vegetation maps remains a critical task for the Air Resources Board.
John F. Karlik – is an environmental science/environmental horticulture advisor with the University of California Cooperative Extension, and an adjunct professor at Bakersfield College. His work has included research at the juncture of botany, chemistry, agricultural, and atmospheric sciences. He has executed a series of field-based biogenic research projects that have provided and validated necessary databases for Biogenic Emissions Inventories through Geographic Information Systems (BEIGIS) simulation platform.