Torry Island Study: (Belle Glade, ): Nutrients in , soil and water of pond apple ( glabra) swamps in relation to restoration Peggy VanArman, Luke Young, Katherine Harvey and Samantha Loutzenhiser

(Photo by George Boyer) Wearing gloves, two researchers collected 25 green and 25 Table 1. Correlation values of standard deviations for leaves (green and senescent): sites 1‐3, Abstract senescent leaves per tree (375 green and 375 senescent per January, April/May, July 2012. sampling event) and placed them into pre‐labeled plastic bags Torry Island juts into southeastern Lake Strong >0.80 very strong >0.90 Comments (1 bag for senescent leaves and one bag for green leaves for Okeechobee just west of Belle Glade, Nitrogen increases, Florida, and provides valuable wildlife each tree). The leaves were then refrigerated and within 24 to 1. TN to TP, positive correlation phosphorus increases MAP habitat through its extensive cypress‐ 48 hours, leaves were removed from bags, rinsed in tap water, TN to C:N Carbon increases, nitrogen pond apple (Annona glabra) swamps. and fresh‐weighed on a top loading Carolina© balance. 2. negative correlation decreases Pond apples were a crucial component of Preparation for analysis required: 1) drying: in a Labconco TP to N:P the historical Everglades and provided Nitrogen increases, Freezone 6© freeze‐dryer at ‐500C for three days; 2) grinding: 3. Site 1 senescent leaves phosphorus increases soil anchoring and nutrient uptake, thus samples from individual trees were ground separately in a Site 2 green leaves reducing nutrient enriched loads of Thomas Wiley mini mill grinder for one minute and the grinder Carbon increases, phosphorus pollutants, such as sediments and 4. TP to C:N, Sites 1 and 2 only increases, nitrogen decreases phosphorus, downstream into the was cleaned in between each sample; 3) ashing: a) for total Collecting pore water samples from soils (Photo by George Boyer) Everglades ecosystem. Phosphorus can phosphorus (TP), green and senescent leaf samples from each be a limiting factor for growth, and tree were separately reduced to dry weight (ash) in a muffle Discussion small changes in concentrations type oven, a one gram subsample was placed in a Lachet Flow Location of test sites on Torry Island in southeastern Lake Okeechobee Torry Island is an important feature of Belle Glade as a natural influence entire communities. While Injection Analyzer©, and phosphorus concentrations were area that could be used as an educational tool for schoolchildren these swamps on Torry Island were largely destroyed by the early 1970’s to make room for settlers and farming interests, some determined using standard methods; b) total nitrogen (TN) and and adults. As a component of Lake Okeechobee, pond apples on remnants exist. Recently, there have been extensive replanting efforts by the Arthur R. Marshall Foundation and South Florida total carbon (TC) were determined from one gram samples Torry Island help to form and anchor soil and are assumed to Water Management District. Although no previous scientific studies to determine nutrient concentrations in pond‐apple leaves placed in a CE Elantech Flash 2000 Elemental Analyzer©, and or trees were found in the literature, one study provided a phosphorus value for soil (Torry muck). Results of the current study store certain nutrients, thus decreasing the amount of pollutants analyzed using standard methods. Nutrients were analyzed by show differences in nutrient values of leaves and soil among the three test sites, and seasonally. Comparisons of values for that flow into Everglades waters. Although TC and TN will be volume. nitrogen and phosphorus concentrations in soil and leaves also show that nutrient enrichment occurs throughout the year at mentioned, this discussion will focus on phosphorus. Phosphorus at all sites. Phosphorus concentrations in soil are higher in surface layers than at depth (to 30 cm). Data indicate differences in is a limiting factor for plant growth in most ecosystems, because it Preliminary analyses of data included calculations of means nutrient values between green and senescent leaves among sites. Strong positive correlations between nitrogen and is crucial for synthesis of ATP, RNA, and DNA, and phospholipids phosphorus, and negative correlations between nitrogen and carbon concentrations were seen in leaves. and standard deviations, concentration ratios, and correlation (Flindt and Lillebo, 2005). Nitrogen is associated with formation of • values (of standard deviations) using Microsoft Office Excel proteins. Fast growing have low C:N and C:P ratios (high N 2007©. Graphs were also developed in Excel 2007©. Grinding leaves for nutrient analyses and P content) and decompose rapidly, while plants with slow Interior of a pond apple swamp during the dry season Introduction Results growth rates have slow litter decomposition rates. P is rapidly Torry island, located in the southeast corner of Lake leached from dead leaf tissue although it may be retained when Okeechobee west of Belle Glade, Florida (Figure 1), is one Three primary sets of results will be discussed. Figure 1 shows the data collected for the five replicate trees shed leaves enter an aquatic environment before they dry out. N of the larger islands in the Lake , approximately 730 acres, (T1‐T5) for green and senescent leaves at the three study sites during three 2012 sampling events. Data has is not generally leached upon senescence and death, although and is owned by the South Florida Water Management not yet been analyzed for statistical significance. initially deceasing concentrations have been observed in some District (O’Dell, 2011). Before development, in the early studies. Plant foliar N:P ratios increase from high to low latitudes 1900’s, the island was a dense swamp dominated by native Total Phosphorus (mol) for All Events (Cleveland and Liptzin, 2007). When organic matter accumulates, Total Phosphorus (mol) pond apple (Annona glabra) and cypress (Taxodium sp.) Site 1 ‐ Green Leaves Site 2 ‐ Green Leaves Site 3 ‐ Green Leaves soil C and N decouple from TP. Site 1 ‐ Senescent Leaves Site 2 ‐ Senescent Leaves Site 3 ‐ Senescent Leaves covered in moonvine (Ipomea alba) with an understory of 0.0125 plants including the endangered Okeechobee gourd The observed values from this study indicate that nutrient (Cucurbita okeechobeensis) (Corkscrew Sanctuary accessed enrichment is occurring on Torry Island, especially when these Oct. 2012). Historically, much of the island was used for data are compared to data from Everglades tree islands. Sklar et This meeting was for the birds, I’m glad we adjourned. 0.0100 farming until the 1970’s, when farming was abandoned due al. (2005) studied TP in leaf tissue from tree island 3AS3 in the (egrets, herons, spoonbills) to improvements to the lake in an attempt to increase Everglades, and found significantly higher values of TP, 0.003781 water levels for storage purposes (Snyder, 2004). mols in pond apple green leaves, compared to a leaf litter values 0.0075 of 0.003281 mols. Coco plum green leaves had significant values of 0.003969 mols, while leaf litter had 0.00403 mols. McCormick Austin (2004) presents a thorough background of Annona Pond apple stand as seen from edge of water spp. It ranges in Florida across the state from southern St. et al. (2002) provide a review of values of P2O5 found in soil in Lucie to Manatee Counties and south through the Keys, 0.0050 different areas of southern Florida: 1) uncultivated land adjacent and also extends to Mexico, Middle America, South to Lake Okeechobee from at a depth of 0‐30 cm contained 2700 America, Peru, and China. Some species produce mg/kg (parts per million‐ppm) of P2O5; 2) muck, marl, and tropical that are eaten by humans, but fruits from A. hammock soil from Tamiami Trail and the Everglades interior 0.0025 glabra, although edible, have a smell resembling ether, or a contained 400 mg/kg; 3) 0‐10 cm samples from Holeyland, and hint of menthol. Seeds, leaves or bark may contain potent Rotenberger areas and the WCAs contained 200‐500 mg/kg. The chemicals that can be used to poison fish or insects, and value of phosphorus required in Everglades waters by the Federal cause blindness and dermatitis. In small quantities, extracts 0.0000 government for Everglades restoration is 10 ppb. T1 T2 T3 T4 T5 T1 T2 T3 T4 T5 T1 T2 T3 T4 T5 Collecting soil core samples can have medicinal uses, and there is a growing body of Feb Apr Aug Conclusions recent literature related to extraction of cancer treatment chemicals from A. glabra (Austin, 2004; Cochrane et al., Figure 1. Summary of Total Phosphorus data for Pond Apple leaves collected during the study 1) Nutrient enrichment by TC, TN, and TP was seen at all sites and on a seasonal basis. 2008). 2) Values of TP in soil appeared to decrease slightly with depth to 30 cm. TP concentrations in both green and Seasonal data, February through July (Figure 1), indicated that total phosphorus (TP) in green leaves on senescent leaves were slightly higher than TP levels in soils. Torry Island provides an opportunity to re‐establish the Torry Island was higher at Site 2 than at Sites 1 or 3, that TP in senescent leaves was lower than in green 3) There were differences in TP among sites. Values of TP in leaves at Site 2 were slightly elevated in relation to values cypress‐pond apple swamp that historically was a major leaves each month, and showed a linear decrease from Site 1 to Site 3. Trends also showed that TP didn’t Pond apple at Sites 1 and 3. TP values in green leaves appeared to be higher than those of senescent leaves at all sites. feature around the southeastern Lake Okeechobee change much in green leaves, but showed a slight decrease in senescent leaves. 4) Seasonal differences in TP indicated that senescent leaves had slightly higher N:P and C:N ratios than green leaves shoreline, but was almost totally eliminated by drainage Figures 2 and 3 show TP concentrations in leaves and soil respectively during the February 2012 sampling during most months. C:N ratios and TC increased in both green and senescent leaves, C:N values for senescent and development (McVoy et al., 2011). Habitat restoration event. This event was chosen for more detailed analysis because it was the only time that soil and leaf data leaves were 50% higher in February than in July. of pond apples within Lake Okeechobee waters provides were collected at the same time. soil stability and enhances water quality to the down‐ 5) Trends from correlation values indicate the following: when TN increases, TP increases; when TC increases, stream Everglades by removing soluble nutrients (such as Focusing on comparing TP in leaves and soil from February, mean TP values for green leaves were: 0.00564 TN decreases; and when TC and TP increase, TN decreases. carbon [C], nitrogen [N] and phosphorus [P]) from the mols (Site 1), 0.00762 mols (Site 2), and 0.00479 mols (Site 3). Senescent leaves had mean values of 0.00561 water and storing these materials as plant tissues and soil. mols (Site 1), 0.00443 mols from Site 2, and 0.00320 mols from Site 3. Soil values ranged in uneven Acknowledgments: Nutrient availability is a driving force in ecosystem species increments from 0.00306 mols at 0‐5 cm to 0.00210 mols at 25‐30 cm (Figure 4), a trend showing an almost This project was supported through the Quality Initiative Grant Program at Palm Beach Atlantic University composition and succession. Thus the concentrations of linear decrease of TP with depth from 0‐30 cm. Although all TP values were elevated, green leaves, administered by Carolanne Brown. Preparation for nutrient analysis from the first collection was undertaken by Ron dissolved forms of C, N, and P, are among the most especially at Site 2 had the most elevated phosphorus levels, and soil values appeared to be lower than Rice, Dr. Mabry McCray and staff at the IFAS lab in Belle Glade, and nutrient analyses were conducted by Len Scinto important factors in plant structuring of communities those of green and senescent leaves. and staff at the FIU analytical lab in Miami. Extra thanks to FIU grad students for transport of samples. Since most (Koerselman and Meuleman, 1996). analyses were conducted at South Florida Water Management District, Field Operations Center, we would like to especially thank David Struve and Meifang Zhou for assistance in preparing and analyzing samples. Without Bob However, nutrient enrichment (N and P) rather than Phosphorus concentrations in leaves of A. glabra Triplett, Natalie Cerolie and other library media specialists at PBAU, the references would not be as complete. We limitation, occurs in Lake Okeechobee due to impacts from February 2012 would also like to thank Carlos Coronado‐Molina (SFWMD) for extensive knowledge of procedures and data analysis, Researchers collecting pond apple leaves for analysis (Photo by George Boyer) Kg crops, pasture, and dairy operations north of the Lake, 10 Kevin VanArman for data analysis and preparation of tables, and Joel VanArman for editing and formatting skills. Last, per

but not least, we thank Boots Boyer, our airboat guide, native of Belle Glade, and owner of a native plant business.

Figure 2. Phosphorus concentrations in Leaves of P including the Everglades Agricultural Area (EAA). Nutrient enrichment is evident spatially and seasonally (Audubon, 8 This project could not have been conducted without his extensive knowledge of Torry Island and its wildlife. 2005; Lodge, 2010; Nair et al., 2012; SFWMD, 2013). In many systems, phosphorus is naturally limiting. However, in Pond Apple collected during February 2012. Each mean represents five trees at each of the 6 Green Lake Okeechobee and surrounding areas, excessive amounts of phosphorus are present in runoff from the three sample sites Bibliography 4 Senescent watersheds and nitrogen is often the limiting factor in plant growth. In typical low‐nutrient ecosystems, such as the Audubon of Florida. 2005. Lake Okeechobee. A Synthesis of Information and Recommendations for Its Restoration. 444 Brickell Ave. Suite 850. Everglades, even small changes in phosphorus concentrations may restructure vegetation and entire communities. 2 Miami, FL. 33131. 79pp. +Lit. Cit. +Appdcs. Millimoles Total Nutrient enrichment can cause algal blooms that block sunlight from benthic plants, resulting in oxygen depletion. 0 Austin, D. F. 2004. Florida Ethnobotany. CRC press, Boca Raton, FL. Pp. 95‐96. Growth of monocultures, such as cattails, (Typha spp.), certain types of cyanobacteria (indicative of an unbalanced Site 1Site 2Site 3 Boyer, G. 2011. The Boyer Survey:An Archelogical Investigation of Lake Okeechobee. George Boyer, Ent. Belle Glade, FL. Palm Beach County ecosystem), and sludge oligochaetes (indicators of pollution) may occur (Audubon, 2005; Lodge, 2012). Enrichment Planning Division permit # 0607.67. can also impact human health in adjacent towns through the presence of bacteria and algal toxins, and formation of Cochrane, C. B., P. K. Raveendran Nair, S. J. Melnick, A. P. Resek, and C. Ramachandran. 2008. Anticancer effects of Annona glabra plant extracts on suspected carcinogens, such as chloroform, when the water is treated with chemicals for public water supply. Phosphorus concentrations in soil at different core human leukemia cell lines. Anticancer Research 28:965‐972.

depths ‐ ‐ February 2012 Cleveland, C. C. and D. Liptzin. 2007. C:N:P stoichiometry in soil: is there a “Redfield ratio” for the microbial biomass? Biogeochemistry 85:235‐ of Redfield ratios (nutrient ratios) or stoichiometry to determine the relative proportions of C, N and P found in plants, 4 252. Kg

Figure 3. Phosphorus concentrations in soil collected Coronado‐Molina, C. 2011. South Florida Water Management District. West Palm Beach, FL. Personal communication. soil and water can be used as a diagnostic tool in aquatic ecosystems as a means to study biogeochemical cycles and during February 2012 . Each mean represents per

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P Flindt, M. R. and . I. Lillebo. 2005. Determination of total nitrogen and phosphorus in leaf litter. Chapter 8. In M. A. S. Graca, F. Barlocher, and M. O. to determine which nutrient might be limiting (Koerselman and Meuleman, 1996; Cleveland and Liptzin, 2007). A three replicate soil cores samples collected at ratio of C:N:P of 160:16:1, respectively is considered to be typical of a balanced system. No studies were found each site. Each core sample was subsampled Gessner (eds.) Methods to study litter decomposition: a practical guide. 2005. Springer, Netherlands. Pp. 53‐59. Soil 2 Total relating to nutrient levels in leaves and water on Torry Island, but one study reported phosphorus levels in soil at 5 cm intervals to determine changes over [TP] Hammar, E. H. 1929. The Chemical Composition of Florida Everglades peat soils with special references to their inorganic constituents. Soil Science depth. 28:1‐11. (Hammar, 1929). In the current study, nutrient levels (total carbon [TC], total nitrogen [TN], and total phosphorus 1 Koerselman, W. and A. F. M. Meuleman. 1996. The vegetation N:P ratio: a new tool to detect the nature of nutrient limitation. Journal of Applied [TP]) were analyzed from water, soil, and pond apple leaf (green and senescent) samples at three sites on a seasonal Ecology 33:1441‐1450.

Millimoles 0 basis. The null hypothesis is that there will be no significant differences (p ≤0.05) among sites or seasons. 0‐5 cm 5‐10 cm 15‐20 cm 20‐25 cm 25‐30 cm Lodge, T. 2010. The Everglades Handbook.Understanding the Ecosystem. 3rd ed. CRC Press, Boca Raton, FL. 392 pp. McCormick, P. , S. Newman, S. Miao, D. Gawlik, and D. Marley. 2002. Effects of Anthropogenic Phosphorus Inputs on the Everglades. Ch. 3. In J. W. Methods Porter and K. G. Porter (eds.) The Everglades, Florida Bay, and Coral Reefs of the Florida Keys. CRC Press, Boca Raton, FL. Pp. 84‐90. The bibliography included, but was not limited to, peer‐reviewed articles from databases such as E.B. Wilson, Bio‐One, N:P values decreased in green leaves, and in senescent leaves the highest value was seen in April. Senescent McVoy, C. W., W. P. Said, J. Obeysekera, and J. A. VanArman. 2011. Landscapes and Hydrology of the Predrainage Everglades. University Press of and Science Direct; EBSCO and newspaper articles; books, video documentaries, and unpublished scientific or leaves had higher values in N:P and C:N ratios most months than green leaves. C:N ratios and TC increased Florida. Gainesville, FL. 342 pp. personal communications (Coronado‐Molina, 2011; O’Dell, 2011; Sharfstein, 2011), and George Boyer Enterprises in both green and senescent leaves, C:N increased over 50% in senescent leaves comparing values in Nair, V. D., M. Chrysostome, and W. G. Harris. 2012. The long term contribution of phosphorus from agricultural lands to Lake Okeechobee. (Boyer, 2011). February to those in July. http://edis.ifas.ufl.edu/SL 357. National Audubon Society. 2013. http://www.corkscrewsanctuary.org/Wildlife/Plants/Profiles/PondApple.pdf. Accessed Oct 2012. Three sites of healthy, old growth pond apple swamps were selected between January 2011 and January 2012 on Torry In general, correlation values (of standard deviations) showed general trends in nutrient concentrations O’Dell, K. 2011. South Florida Water Management District. West Palm Beach, FL. Personal communication Island and locations were marked using Garmin e‐Trex© GPS units. The size of each plot and the number and sizes of (Table 1) as follows: 1) Strong positive correlations were seen in TN:TP ratios. When nitrogen increases, Sharfstein, B. 2011. South Florida Water Management District. West Palm Beach, FL. Personal communication. pond apple trees inside plot boundaries were estimated. At each site, two stations were selected for collection of soil phosphorus increases. 2) Very strong negative correlations between TN and the C:N ratio, indicating that Sklar, F. H., C. Coronado, S. Newman, S. Krupa, P. Wetzel, M. Ross, T. Troxler, P. Sullivan, M. Graf, G. Chmura, and B. Orem. 2005. The State of Our and three stations for pore water [see student posters of Katherine Harvey (soil) and Samantha Loutzenhiser (water) when carbon increases, nitrogen decreases. 3) Strong positive correlations of TP to N:P were found at Site 1 Understanding of the Biogeochemical Processes on Tree Islands in the Greater Everglades. Powerpoint. for their procedures]. Five trees were randomly selected for collection of green and senescent (ageing or degrading) in senescent leaves and at Site 2 in green leaves, when nitrogen increases, so does phosphorus. 4) At Sites 1 Snyder, J. D. 2004. Black Gold and Silver Sands. Historical Society of Palm Beach County. 215 pp. leaves at each site. Indicator trees were measured to determine height and Diameter at breast Height (DBH). Each and 2 only there was strong negative correlation of TP to C:N, when carbon increases, phosphorus South Florida Water Management District. 2013. DRAFT 2013 South Florida Environmental Report. Accessed October 29, 2012 at indicator tree was marked with numbers one through five using red paint, and bright yellow tape was attached. A increases, nitrogen decreases. http://my.sfwmd.gov/portal/page/portal/pg_grp_sfwmd_sfer/portlet_prevreport/2013_sfer_draft/2013_sfer. Chapter 8: Lake Okeechobee Watershed Protection Program, by Joyce Zhang and Bruce Sharfstein. 84 pp. seasonal collection schedule was set up for the months of January, April, July, and October, 2012.