The ethnoecology and autecology of white root (Carex barbarae Dewey): Implications for restoration.

摘要

Traditional environmental knowledge has a great deal of detailed knowledge to contribute to restoration. The synergism of restoration and traditional resource management creates an expanded repertoire of restoration objectives and management strategies. The modern challenge is to restore both cultural and ecological health through understanding the relationship between humans and the ecosystems they managed.; This study evaluates the traditional resource management of white root (Carex barbarae) by California Indian groups. White root is an herbaceous perennial understory plant in valley oak riparian woodlands, which today occupy only 5% of their pre-European settlement area. It is one of the most difficult plants for basketweavers to obtain due to elimination and privatization of traditional gathering sites. Before European settlement, hundreds of thousands of white root rhizomes were sustainably harvested annually by California Indian women Traditional resource management created homogeneous patches of white root throughout the low-elevation riparian forests of California, maintaining a lawn-like understory and a park-like physiognomy.; Horticultural methods utilized by California Indians formed the basis for both mesocosm and in situ experiments designed to test the effects of traditional resource management on the growth and production of Carex barbarae. Horticultural techniques which were experimentally tested included plant density, harvest intensity and soil type. I determined that Carex biomass and rhizome production were highest in peat soil, less in loam, and lowest in clay and sand. These data appeared to contradict traditional Native American wisdom that the longest rhizomes grow in sand soil.; I postulated that reduced biomass production and rhizome growth in sandy soil were a result of nutrient limitations, since the mesocosm experiments were carried out in conditions isolated from the nutrient influx which accompanies flooding. A nitrate fertilization experiment tested plant growth and reproduction under high- and low-nutrient environments. Carex barbarae responses in low nutrient environments include the following: longer rhizomes; lower total biomass; increased below-ground biomass; high root:shoot ratios; increased retranslocation of nitrogen and phosphorus; higher nitrogen use efficiency; and lower fecundity. As nitrogen supply increased, total plant biomass and fecundity increased and nitrogen use efficiency (NUE) decreased.