THE EDWARDS AQUIFER and its Unique Ecosystem – potential threats from Groundwater Management Glenn...
-
Upload
leslie-bond -
Category
Documents
-
view
217 -
download
3
Transcript of THE EDWARDS AQUIFER and its Unique Ecosystem – potential threats from Groundwater Management Glenn...
THE EDWARDS AQUIFER and its Unique Ecosystem –
potential threats from Groundwater Management
Glenn LongleyDirector
Edwards Aquifer Research & Data Center
2
Outline
Hydrologic Setting of Edwards (BFZ) Aquifer
Unique Aquatic Ecosystem History of Management Current work Summary Contact information
3
Edwards AquiferSan Antonio portion of FZ
WatershedWatershed
RechargeRecharge ZoneZone
ArtesianArtesian ZoneZone
SM spgs
Comal spgs
SA spgs
Leona spgs
Elevation near 1400 feet ↘
•Elevation near 575 feet ↘
5
6
7
8
9
10
San Marcos Springs
11Barton Springs Segment (BFZ) Aquifer
12
Unique? How?
40+ species of Invertebrates 4+ species of Vertebrates
13
Discoveries made in the last 20 years
Diversity of Amphipods, snails & overall Presence of marine relicts
Monodella Some amphipod families Foraminiferans
New species, deep aquifer system More detailed information about vertebrates
14
Community diversity
Greatest in Amphipods (12 species-5 families)
Other Arthropods (13 species representing 8 families)
Next is Mollusca (10 species of Hydrobiid snail family)
15
More about diversity
Biological diversity is important - Ecological stability
The species in this system may hold important genetic information
16
Marine relicts
Amphipods in the families: Hadziidae, Bogidiellidae, & Sebidae
These families are primarily marine with few examples of freshwater sp.
Hadziids are distributed today around the Caribbean and Mediterranean
These areas are important as remnants of the Tethys Sea
17
Marine relicts
May assist in better understanding of how the aquifer formed and its relationship with paleomarine areas
Additional studies of these species will shed light on paleogeography
18
Other marine relicts in the Aquifer
Monodella texana (Only N.A. Thermosbaenacean)
M. texana’s marine ancestors are represented by groups in the W. Indies
A Foraminiferan from the Lagenidae (Probably Robulus sp) was found
19
Other marine relicts continued
Foraminiferans have only been found in fresh water from wells (Trans Caspian Province)
Cirolanid isopods (predominantly marine) are also found
20
New species
8 new snails, 2 others renamed 10 new amphipods, 1 new family (Artesiidae) 1 new aquatic beetle - Hadeoporus texanus (larvae
& adult described) 1 new vertebrate described - Typhlomolge robusta
21
Flowing Edwards well with biomass being discharged southwest of San Antonio, Texas
22
Texas State University Artesian Well
Drilled in 1895 to furnish water for Federal Fish Hatchery
Five foot cavern at 195 feet
Source of water is Edwards Aquifer
Sampled continuously since early 70’s
23
64 micron mesh net on 12” discharge with removable sample chamber
24
Two day sample out of Texas State Artesian well net
25
Filamentous colonies of fungi and other organisms
26
Placing a net on flowing well at San Antonio Zoo
TURBELLARIA: (Flatworms) Kenkiidae Sphalloplana mohri Hyman NEMATODA: (Roundworms) Rhabdochonidae Rhabdochona longleyi Moravec & Huffman
Invertebrate Fauna
28
Sphalloplana mohri
29
Gastropods (Snails) Hydrobiidae Phreatodrobia conica Hershler &
Longley Hueco cavesnail
P. coronae Hershler & Longley
P. imitata Hershler & Longley mimic cavesnail
P. micra (Pilsbry & Ferris) flattened cavesnail
P. nugax inclinata Hershler & Longley
P. nugax nugax (Pilsbry & Ferris) domed cavesnail
P. plana Hershler & Longley disc cavesnail
P. punctata Hershler & Longley high-hat cavesnail
P. rotunda Hershler & Longley beaked cavesnail
Phreatoceras taylori Hershler & Longley nymph trumpet
Balconorbis uvaldensis Hershler & Longley Balcones ghostsnail
Stygopyrgus bartonensis Hershler & Longley Barton cavesnail
Texapyrgus longleyi Thompson & Hershler striated hydrobe
30
31
HIRUDINEA(Leeches)
Erpobdellidae: Mooreobdella microstoma Pawlowski
32
Crustaceans
OSTRACODA: Entocytheridae
Sphaeromicola (Hobbsiella) moria
Hart
ISOPODA: Cirolanidae Caecidotea reddelli (Steeves) Cirolanides texensis Benedict Asellidae Lirceolus pilus (Steeves) L. smithi (Ulrich) Texas
troglobitic Water Slater Mexistenasellus sp.
33
Asellid Isopod
34
Mexistenasellus sp.
35
AMPHIPODS
Hadziidae Allotexiweckelia hirsuta Holsinger Holsingerius samacos (Holsinger) Texiweckelia texensis (Holsinger) Texiweckeliopsis insolita (Holsinger)
Amphipods continued
Stygobromus balconis (Hubricht)
Crangonyctidae
S. bifurcatus (Holsinger)
S. flagellatus (Benedict)
S. pecki (Holsinger)
S. russelli (Holsinger)
Sebidae
Seborgia relicta Holsinger
Bogidiellidae
Artesia subterranea Holsinger
Parabogidiella americana Holsinger
37Stygobromus sp.
CRUSTACEANS continued
THERMOSBAENACEA: Monodellidae Monodella texana Maguire
DECAPODA: Palaemonidae Palaemonetes
antrorum Benedict P. holthuisi Strength
39
Monodella texana
40Paleomonetes antrorum
41
COLEOPTERA:(Insect – beetles)
Dryopidae Stygoparnus comalensis Barr & Spangler Dytiscidae Comaldessus stygius Spangler & Barr Haideoporus texanus Young & Longley
Edwards Aquifer water beetle
42
Haideoporus texanus
43
VERTEBRATESPISCES: (Fish)
Ictaluridae Satan eurystomus Hubbs & Bailey
Widemouth blindcat Trogloglanis pattersoni Eigenmann
Toothless blindcat
44
Satan eurystomus
45
Trogloglanis pattersoni
Toothless blindcat Found in same area of
Widemouth Blindcat Shallowest collection
1350’ below surface Deepest 2000’ Only below San
Antonio TX area
46
CAUDATA:Tailed amphibians
Plethodontidae Eurycea chisholmensis Chippindale,
Price & Hillis Salado salamander E. latitans Smith & Potter Cascade Caverns salamander E. naufragia Chippindale, Price &
Hillis E. sp.nov. Comal E. nana Bishop San Marcos salamander E. neotenes Bishop & Wright Texas salamander E. pterophila Burger, Smith & Potter Fernbank salamander E. rathbuni (Stejneger) Texas Blind salamander
E. robusta (Longley) Blanco Blind salamander E. sosorum Chippindale, Price & Hillis Barton Springs salamander E. tonkawae Chippindale, Price &
HillisJollyville salamander E. tridentifera Mitchell & Reddell Comal blind salamander E. troglodytes Baker Valdina Farms salamander E. sp. Comal Springs salamander
47
Eurycea rathbuni Texas Blind Salamander
48
49
San Antonio portion of the Balcones Fault Zone Edwards Aquifer
50
Bexar Co. Texas “Catfish Well” flows at > 30 MGD
51
History of Management 1983 - EUWD given authority to regulate
transport of water out of district (5 counties) 1987 – EUWD gains legislative approval
for a drought management plan (DMP) 1988-90 – DMP requirements set 1989 – Two western Counties withdraw
from District May 1991 – SA defeats construction of
Applewhite Reservoir (Alternate source) May 1991 – Sierra Club files suit against
USFWS
52
History Continued Sierra Club suit asks that USFWS be
required to insure min. springflow to protect endangered species.
EUWD and SARA file suit against Living Waters (Catfish Well owners) for waste and water quality issues.
1992 – TWC declares Edwards Aquifer to be an underground river, therefore regulated by the state
Later that year State Court invalidates TWCs determination
53
History continued Nov 16, 1992 Trial begins in U.S. District
Court for Sierra Club lawsuit. Jan 30, 1993 – U.S. Dist. Judge Bunton rule
for the Sierra Club and orders:Springflow must be maintainedTWC must submit plan to court by March 1993
to assure Comal & San Marcos Springs do not drop below Jeopardy levels
USFWS must develop springflow thresholds for take & jeopardy
Tx Legislature must develop regulations to limit withdrawals by May 31, 1993.
54
History continued May 30, 1993 – Texas Legislature adopts
SB 1477 that creates the Edwards Aquifer Authority (EAA) with a 9 member appointed board
Aug. 30, 1993 – U. S. Justice Dept. ruled legislation may have violated the Voting Rights Act, in November they determined it did
Feb. 1994 – Fed. Court Appointed monitor to gather information for the court.
Hydrologic
Less storage in aquifer (1ft of head = approx. 35,000 acre feet).
Low flows of San Marcos Springs occur sooner during critical dry periods.
Greater potential for saline water intrusion during critical periods.
Ecological
Lower flows would possibly jeopardize listed species sooner.
57
Threats to the system Historic lows vs. recent time (recharge &
discharge) Increasing water use Aquifer Storage & recovery Proposed policy to raise pumping caps Proposed policy to limit minimal pumping
required during drought
Summary
59
Detailed studies (Past & Continuing)
Texas Blind Salamander - Typhlomolge rathbuni Two blindcatfish from San Antonio area: Satan
eurystomus & Trogloglanis pattersoni (Ictaluridae)
Distribution of species throughout the aquifer, important in showing hydrologic relationships
60
Studies currently underway
Water Quality - investigating freshwater/saline water interface
Modeling of groundwater hydrology and the effect of pumping
61
This system is a microcosm of problems in our world
Population growth and human demands threaten the system and the surface ecosystems (springs) it supports
We should educate the users of water from the aquifer about its dynamics
Its importance as the habitat for a community of organisms
62
Additional studies needed
Biomagnification of contaminants up the aquifer food chain
Toxicity studies of specific members of the aquifer community
Additional studies of rarer species Energy flow and sources in the deep
confined aquifer
63
Acknowledgements The work on the aquifer through the years
has been supported by USFWS, TPWD, USDA, USEPA and numerous other sources too numerous to mention.
Staff of the Research Center, Graduate Students, Collaborators and numerous others have assisted in developing the information about the Aquifer community.
Texas State University has been very supportive of this work.
Thank you!
I can be reached at the following: email: [email protected] EARDC homepage:
http://www.eardc.txstate.edu Phone: 512-245-3581 Fax: 512-245-2669 Feel free to contact me with questions.