1. Luquillo Biocomplexity Meeting January 2004
Hydrology overview
Stream-Hydrology issues
Pike/Scatena research plan

3. Steep Environmental Gradients
Subtropical Dry (1200 mm/yr) to Wet (5000mm/yr)
Windward vs leeward

4. Hydrology Overview Steep Environmental Gradients
Maritime climate with high rainfall frequency minor seasonality
3 rain showers/day, High interception,
Intense rainfalls; >500 mm/day, 125 mm/day threshold; Hurricanes, TS, northern fronts
Dynamic disturbance regime
Hurricanes, landslides, tree-falls
Old on inside-young on outside

5. Seasonality of Luquillo Climate
May
Rains

6. Forest Wide Temperature
Based on regression of Temp vs elevation, aspect

7. Wet Season
Dry Season

8. Hydrology Overview Steep Environmental Gradients
Maritime climate with high rainfall frequency minor seasonality
Dynamic disturbance regime
Hurricanes, landslides, tree-falls
“Old on inside-young on outside”

9. Hillslope processes Deep Clayey soils; 6 + m of saprolite
Volcanoclastics vs Grandiorite
Hillslope Catena’s
Shallow flow paths; < 1 m
through-flow vs overland flow
soil compaction, trail erosion
Landslides; yr turnover
roads, elevation, bedrock
Larsen, Zarin, Walker

10. Bisley Hillslope profile
Soil and saprolite m thick
Storage; at 1% water content = mm; 1 month throughfall

11. Clay and saprolite subsoil with relatively low ksat = low recharge

12. Storm hydrographs
H20
Na, Mg
Ca, CL

13. Stream Channel Hydrology
Headwaters
Steep gradient, boulders, structural control
Supply limited
“clean water”
Coastal plain
Alluvial and channelized
Relatively stable planform morphology
Aggradation/degradation cycle

14. Annual 7 day
Minimum
Q90
Q50
Xiphocaris spp. Night
Atya spp. Night

15. Daily Discharge Series
No Extraction
Extraction = Q95, No Minimum In-stream Flow
Extraction = Q95, Minimum In-stream Flow = Q99

16. General Hydrologic/land use issues
Municipal water withdrawal
aquatic migrations
Urbanization
Reservoir sedimentation
USGS, landslides
Coastal Plain deforestation
RAMS model

17. Regional-scale changes
Synoptic
Systems
Tradewinds
Energy &
Moisture
Land-Sea
Tectonic
Uplift
Sea
Level

19. On-going research efforts
GIS based-statistical models
Garcia; low flow prediction, Rivera; peak discharges, Santos; island wide water chemistry
Simulation models
Hall SUNY-ESF; Soil carbon, ET
Interception and cloud forest hydrology
Free University of Amsterdam
Stream water chemistry, N cycling
W. McDowell, UNH
Instream flows and water withdrawals
Pringle UGA

20. Roads Facilities Water Intakes Roads & Maintenance Buildings
Communication
Facilities
Water
Intakes
Roads &
Maintenance
Buildings

21. Stream/road issues Hydrologic issues
Freeze-thaw
Groundwater discharge
Flooding
overbank, diversion flooding
Erosion of unpaved roads
Damage to bridges and culverts
Landslides

22. Stream/Road-Chemical issues
Applied chemicals (e.g. road salt..)
minor herbicide use
Road material
asphalt, dirt
Emissions
Odum Co2
Chemical spills
Swimming

23. Social considerations
Social significance of Luquillo Streams
Seasonality of recreation
locals vs snowbirds
don’t go to beach in months with “R”
Short travel distances and short storms
Shystostomisis and “dirty” streams
Swimming skills

24. Current Biocomplexity Efforts

25. Channel morphology-aquatic habitat
GIS-Statistical based approach
Develop null then evaluate road crossings
Work Plan
Aug 2003; channel cross-sections
Fall 03; GIS layers
Jan 2004; pebble counts
Spring 04; develop manuscript I
Summer 04; Espirtu Santo, bridges
2005; bridge habitat analysis, water falls…

29. Slope Raster

30. Channel slope vs Drainage area
Sonodora = 2.6 km2
Puente Roto = 17.8 km2
Mameyes at RT3 = 34.7 km2

31. Drainage Area vs Channel Width

32. Slope
Mean grain size/Basin area