Long Term Evaluation of Characteristics in an Artificial Northern California Vernal Pool System

摘要

This report (Phase II) completes an evaluation of 3 sets of 5 artificial vernal pools located on Travis AFB in Solano County CA. The research was done to determine if artificial vernal pools constructed on Travis AFB in 1993 maintained vernal pool characteristics and to determine if any of the five treatments used to develop the artificial pools are useful for mitigating vernal pool impacts. Phase II consisted of collecting data during the spring of 2002 from artificial pools and the source pools (TR1-TR5) to determine the vegetative success of the vernal pools over time. The artificial vernal pools support a diverse plant population, but lack the vegetative diversity of natural pools. The artificial pools exhibited zonation of plant species correlating with the length of inundation. The greater depth of the artificial pools allowed longer inundation periods than occurred in the nearby natural pools. Plant species associated with longer inundation periods (Plagiobothrys stipitatus, Eryngium aristulatum) are benefiting from the design of the artificial pools. By collecting data during Phase II, and comparing that data with previously collected data we determined that plant species vary from year to year in artificial and natural vernal pools at Travis AFB. Navarretia intertexta, Epilobium pygmaeun, and Lythrum hyssopifolium were present in 2002, but absent in last year's data (2001).