Ecology 6th Edition by Charles Krebs

تمرين 11

The saguaro is a prominent columnar cactus of the Sonoran Desert of Arizona and northern Mexico. Saguaro are long-lived perennials, and individuals may reach 150-200 years of age. Pierson and Turner (1998) reported the following data from a long-term study of four populations in an ungrazed desert preserve:
What would you conclude about the population dynamics of these cacti from these data? What additional data would you like to have to predict future population trends?