Paul McCormick
William Orem
Unpublished Material
Effects of water hardness on slough-wet prairie plant communities of the A. R. M. Loxahatchee National Wildlife Refuge
http://sofia.usgs.gov/projects/hardness_swp/
Alterations to ground-water and surface-water hydrology and water chemistry in South Florida have contributed to increased flows of mineral-rich (hard water) canal water into historically rain-fall driven (soft water) areas of the Everglades. The interior of the A. R. M. Loxahatchee National Wildlife Refuge largely has retained its historic low conductivity or soft water condition due to its relative isolation from canal flows. However, recent sampling by USGS and the Refuge has shown that canal influences on water quality extend several kilometers into the Refuge in some areas, and Refuge managers and scientists are concerned that these influences may increase depending on future changes in water management operations.
A survey across existing mineral gradients will be performed to document patterns of vegetation change and their relationship to changes in water hardness and other environmental factors. Laboratory and field experiments will test these correlative relationships to determine the relative importance of increasing water hardness as a cause of observed vegetation changes across canal gradients.
Intrusion of canal waters into the Refuge increases the availability of Phosphorus (P), the primary limiting plant nutrient in the Everglades, as well as concentrations of major mineral ions such as Ca 2+, Mg 2+ and SO4 2-. While the ecological effects of P enrichment on the Everglades is fairly well understood, potential impacts caused by increased mineral concentrations in this soft-water wetland are largely unknown. Understanding the types and magnitude of these impacts is particularly important given that the area of the Refuge exposed to mineral enrichment is much greater than that exposed to P enrichment.
The objective of this project is to determine the effects of increased flows of mineral-rich water on the aquatic plant community of the Refuge interior. Slough-wet prairie (SWP) habitats area a major landscape feature in the Refuge and several SWP plant species may be adapted to the soft-water conditions in the Refuge interior. Increased mineral loads to the Refuge may result in a shift towards a more species-poor and spatially homogeneous community, In addition, there is a small amount of evidence to suggest that mineral enrichment may favor the growth and expansion of sawgrass and a consequent decline in the coverage of the SWP habitats.
2006
Unknown
ground condition
As needed
A.R.M. Loxahatchee National Wildlife Refuge
-80.5
-80.25
26.7
26.3
none
biology
chemistry
hydrology
major ions
phosphorus
slough
wet prairie
ISO 19115 Topic Category
environment
inlandWaters
biota
002
007
012
Department of Commerce, 1995, Countries, Dependencies, Areas of Special Sovereignty, and Their Principal Administrative Divisions, Federal Information Processing Standard (FIPS) 10-4, Washington, DC, National Institute of Standards and Technology
United States
US
U.S. Department of Commerce, 1987, Codes for the identification of the States, the District of Columbia and the outlying areas of the United States, and associated areas (Federal Information Processing Standard 5-2): Washington, DC, NIST
Florida
FL
Department of Commerce, 1990, Counties and Equivalent Entities of the United States, Its Possessions, and Associated Areas, FIPS 6-3, Washington, DC, National Institute of Standards and Technology
Palm Beach County
USGS Geographic Names Information System
Arthur R. Marshall- Loxahatchee National Wildlife Refuge
none
Greater Lake Okeechobee
none
plants
U.S. Department of Agriculture - Agricultural Research Service (ARS)
U.S. Department of Agriculture - Natural Resources Conservation Service (NRCS)
Department of the Interior - U.S. Geological Survey
Department of Commerce - National Oceanic and Atmospheric Administration (NOAA)
Environmental Protection Agency (EPA)
Smithsonian Institution - National Museum of Natural History (NMNH)
2000
Integrated Taxonomic Information System (ITIS)
Database
Retrieved from the Integrated Taxonomic Information System on-line database, http://www.itis.gov.
http://www.itis.gov
plants will be identified in the field or specifically collected for the laboratory experiments
unknown
plants are identified to the species level
Kingdom
Plantae
plants
Division
Magnoliophyta
angiosperms
Class
Liliopsida
monocotyledons
Sub Class
Commelinidae
Order
Eriocaulales
Family
Eriocaulaceae
pipeworts
Genus
Eriocaulon
pipewort
Species
Eriocaulon compressum
flattened pipewort
Order
Cyperales
Family
Cyperaceae
Sedge family
Genus
Eleocharis
spikerush
Species
Eleocharis cellulosa
Gulf Coast spikerush
Order
Commelinales
Family
Xyridaceae
yellow-eyed grass
Genus
Xyris
xyris
yelloweyed grass
Species
Xyris smalliana
Small's yelloweyed grass
Class
Magnoliopsida
dicots
docotyledons
Subclass
Asteridae
Order
Solanales
Family
Menyanthaceae
bog beans
Genus
Nymphoides
floatingheart
nymphoides
Species
Nymphoides aquatica
big floatingheart
none
none
Paul McCormick
Lake Okeechobee Division, South Florida Water Management District
mailing and physical address
3301 Gun Club Road
West Palm Beach
FL
33406
USA
561 682-2866
561 640-6815
pmccormi@sfwmd.gov
Project personnel include Rebekah Gibble (USFWS) and Eric Crawford (USGS).
not available at present
not available at present
Field survey (gradient study)
The Refuge will be surveyed during fall of FY06 to determine the distribution of common SWP plant species and the extent of SWP habitat with respect to water and soil chemistry. Thirty locations will be selected that encompass a range of hydrology and water chemistry. Severely overdrained areas at the north end of the Refuge, deepwater areas at the south end, and highly enriched cattail area near canals will be excluded as vegetation in these areas is clearly driven by hydrology and/or P.
The frequency of occurrence of common SWP species will be determined in 24 1-m2 quadrats placed at roughly 2-m intervals along a transect across the center of this habitat. An additional 5 minutes will be spent surveying the site to detect species present in lower abundance. Voucher specimens will be collected and repeat visits will be made later in the year to assure accurate taxonomic identifications. Aerial photography of the Refuge obtained by Palm Beach County in 2004 will be used to determine the percent coverage of SWP (as opposed to sawgrass, tree island, and brush) habitat at each site. Water depths and soil and water chemistry (pH, surface-water conductivity, soil Ca and total and extractable P and N concentrations) also will be measured at each site. Additional water chemistry data will be obtained from monthly water-quality monitoring trips conducted at each site by the Refuge and SFWMD.
Data will be analyzed using simple correlations, multiple regressions, and multivariate analysis to identify patterns of species distributions and habitat cover with respect to chemical variables and depth. These analyses will generate testable hypotheses concerning the importance of water hardness vs. other environmental factors in determining the size and vegetation composition of SWP habitats.
200610
Effects of mineral and P enrichment on sawgrass and SWP communities and cover
Sets of 4 walled enclosures (2.5 m x 1.25 m) will be established at 3 locations (for a total of 12 enclosures) near an interior monitoring station (LOX8) in the Refuge. Enclosures will be located in the transition zone between sawgrass and SWP habitats such that approximately half of each enclosure is within each habitat. Vegetation composition and tissue chemistry will be measured in each enclosure during February 2007. Once this baseline assessment is completed, enclosures will be enriched with one of the following substances: 1) no enrichment (control); 2) crushed limerock (mineral, pH treatment); 3) slow release P fertilizer (nutrient enrichment); 4) both limerock and P enrichment. Each treatment will be applied to 1 enclosure in each set for a total of 3 replicates per enrichment treatment. Surface soils will be collected from each enclosure 1 month after the first dose is applied and processed to determine pH, mineral content, and available P. Additional doses will be applied quarterly or more frequently as required to maintain elevated levels of these chemical parameters in applicable treatments. Vegetation responses will be measured after 6 months and every 6 months thereafter. Dosing will continue through FY08.
Not complete
Laboratory experiment to determine the effects of increased mineral and P loading on sawgrass growth in sloughs
Sawgrass seeds from a common seed source will be germinated in the laboratory. While still small (~2-3 cm high), seedlings will be transplanted to small pots containing 500 g of soil from an interior slough in the Refuge. Initially, soils will be amended with a mineral solution containing major ions in the same proportions as found in canal water and with P in different combinations. Plants will be grown for 3 months under a temperature and photoperiod indicative of spring-time conditions in south Florida and watered 1-2 times each week with the same solutions used for soil amendment. The growth rate (increase in height) of replicate plants in each treatment will be measured over a 3-month period and final biomass will be determined. Initial and final soil pH and nutrient and mineral chemistry will be measured.
Not complete
Response of a submerged aquatic plant, Eriocaulon compressum, to mineral enrichment
Twenty-four E. compressum plants of similar size will be collected from a peat pop-up at an interior location in the Refuge. Plants will be shipped overnight to the laboratory and weighed to obtain initial wet weights. Twelve plants will be potted in interior slough soil (low mineral content) in deep plastic containers and the remaining 12 will be planted in soils from a canal-influenced slough (higher mineral content). Plants of each soil treatment will be subjected to the following hydrologic treatments (4 replicate plants each): 1) watering to maintain saturated conditions; 2) watering to maintain flooding approximately 1/2 way up the above-ground portion of the plant; 3) flooding to submerge the plant under several cm of water. Plants grown in low mineral soils will be watered weekly with mineral-poor water from the same collection site. Plants grown in higher mineral soils will receive the same water that has been amended with a mineral solution to approximate 50% of the ionic strength of canal water, a mineral content that periodically occurs in sloughs near the Refuge perimeter in response to canal-water intrusion. Plants in flooded treatments will be acclimated gradually by raising water levels a few cm each week. Thus, for example, it will take about 5 weeks to completely flood plants in the submerged treatment.
Plants will be grown for 3 months under a temperature and photoperiod indicative of spring-time conditions in south Florida. Water pH and conductivity will be monitored weekly in each flooded container and concentrations of major cations and anions (mineral content) will be measured every 2-3 weeks. Care will be taken to avoid excessively high mineral concentrations by adding unamended interior slough water or distilled water as needed to account for evaporation. Plant height and diameter will be monitored for 3 months. The extent of browning of each plant also will be measured as an indicator of stress. At the end of the experiment, plants will be harvested to measure final biomass and tissue chemistry. Final water and soil mineral concentrations and pH will be measured.
Not complete
Response of the floating aquatic plant, Nymphoides aquaticum, to mineral enrichment
Several plants of N. aquaticum will be collected from an interior slough in the Refuge during February 2007. Collection of this species at this time of the year is facilitated by the abundance of small, free-floating specimens produced asexually by fragmentation. Plants will be shipped overnight to the laboratory, weighed to obtain initial wet weights, and measured for leaf number and size. Soils from an interior (low mineral content) and perimeter (high mineral content) slough will be combined in the following wet-weight ratios and used to fill the bottom of replicate containers: 1) 100%L:0%H; 2) 75%L:25%H; 3) 50%L:50%H; 4) 25%L:75%H; 5) 0%L:100%H. Soils in these respective treatments will be flooded with water from an interior location that has been amended with minerals to achieve 0, 25, 50, 75, or 100% of the increased ionic strength of canal water over interior surface water. Additional treatments will combine selected mineral treatments with P enrichment. A seedling will be placed in each container and allowed to grow and root for 3 months under a temperature and photoperiod indicative of spring-time conditions in south Florida. Water specific conductance and pH will be monitored weekly and water mineral and P chemistry will be measured every 2-3 weeks. Leaf number and size will be measured monthly. At the end of the experiment, plants will be harvested to determine final biomass and tissue chemistry. Final soil and water chemistry will be measured.
Not complete
Competition Experiment
This experiment is currently being designed, but anticipated methods are as follows. Large (e.g., 20 L) pots will be filled with soils from either an interior (low minerals and nutrients) or perimeter (high minerals and nutrients) SWP. Pots of each soil type will be planted with dominant interior (Xyris, Eriocaulon, Nymphoides) and perimeter (Eleocharis cellulosa) SWP taxa either separately or in combination. Replicate pots of each soil-plant treatment will be maintained under either slightly flooded (e.g., 10 cm) conditions that are representative of interior SWPs or under deeper and fluctuating water depths (e.g., 10-30+ cm) that are more representative of perimeter SWPs. The experiment will be maintained in large water troughs at Refuge headquarters for a minimum of 12 months, and plant growth and survival will be measured quarterly. Initial and final soil and plant-tissue chemistry will be measured.
Not complete
Paul McCormick
Lake Okeechobee Division, South Florida Water Management District
mailing and physical address
3301 Gun Club Road
West Palm Beach
FL
33406
USA
561 682-2866
561 640-6815
pmccormi@sfwmd.gov
20080114
Heather Henkel
U.S. Geological Survey
mailing and physical address
600 Fourth Street South
St. Petersburg
FL
33701
USA
727 803-8747 ext 3028
727 803-2030
sofia-metadata@usgs.gov
Content Standard for Digital Geospatial Metadata Part 1: Biological Data Profile
FGDC-STD-001.1-1999