Urban Tree Mortality: a Primer on Demographic Approaches.

摘要

Realizing the benefits of tree planting programs depends on tree survival. Projections of urban forest ecosystem services and cost-benefit analyses are sensitive to assumptions about tree mortality rates. Long-term mortality data are needed to improve the accuracy of these models and optimize the public investment in tree planting. With more accurate population projections, urban forest managers can also plan for cycles of tree planting, death, removal, and replacement to achieve canopy cover goals. Analytical tools from demography, such as life tables and mortality curves, could be used to improve our understanding of urban tree mortality and longevity. Demographic approaches have been widely used in forest ecology to quantify population dynamics and project future changes in wildland systems. This report is a primer on demographic concepts applied to urban trees, with terms and analytical methods adapted to the cultivated urban landscape. We include an overview of the uses of urban tree mortality rate data for research and management, a summary of lessons learned from ecological monitoring in other systems, and a discussion of opportunities for long-term urban forest monitoring by researchers and practitioners.