HR: 1330h
AN: B52A-1025    [PDF]
TI: Response of Stream to Variation in Vegetation in Pedernales Watershed
AU: * Shen, L
EM: shenli@tamu.edu
AF: Bradford Wilcox, 2126 TAMU, College Station, TX 77840 United States
AU: Wilcox, B
EM: bwilcox@tamu.edu
AF: Bradford Wilcox, 2126 TAMU, College Station, TX 77840 United States
AB: Natural water level changes in an aquifer are mainly due to changes in the groundwater recharge and discharge conditions of the aquifer. Increased stream flow in response to brush removal will be most apparent in springs and small headwater streams, because small increases in subsurface flow are unlikely to create measurable in discharge of mainstream channels located downstream (Wilcox, 2002). The major objective of this study tries to estimate the flow of springs responding from brush management. In this research, we measured and reported on the flow at 30 spring sites during the summer in 2003. There are twelve springs in Blanco County, and the others are in Gillespie County. There are three spring sites with heavy salt cedar in the upper watershed, four spring sites with moderate salt cedar in the upper watershed, six spring sites with light salt cedar in the upper watershed, fourteen spring sites with grassland and oak woodland, and three spring sites in the grassland without salt cedar. Because there is significant heterogeneity of flow between different vegetation types, we regroup the amounts of flow with same interval into seven groups. The highest average amount of flow is with grassland and oak woodland, and the lowest average amount of flow is with grassland. The amounts of flow are significant different between vegetation types (Chi-Square $< 0.01$). Spring flow is low in grassland. More springs dried out in the sites with salt cedars or oak woodland.
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2003 Fall Meeting