Kissimmee River Research Articles

SEDIMENT DYNAMICS IN THE RESTORED REACH OF THE KISSIMMEE RIVER BASIN, FLORIDA: A VAST SUBTROPICAL RIPARIAN WETLAND

ABSTRACTHistorically, the Kissimmee River Basin consisted of a broad nearly annually inundated riparian wetland similar in character to tropical Southern Hemisphere large rivers. The river was channelized in the 1960s and 1970s, draining the wetland. The river is currently being restored with over 10 000 hectares of wetlands being reconnected to 70 river km of naturalized channel. We monitored riparian wetland sediment dynamics between 2007 and 2010 at 87 sites in the restored reach and 14 sites in an unrestored reference reach. Discharge and sediment transport were measured at the downstream end of the restored reach. There were three flooding events during the study, two as annual flood events and a third as a greater than a 5‐year flood event. Restoration has returned periodic flood flow to the riparian wetland and provides a mean sedimentation rate of 11.3 mm per year over the study period in the restored reach compared with 1.7 mm per year in an unrestored channelized reach. Sedimentation from the two annual floods was within the normal range for alluvial Coastal Plain rivers. Sediment deposits consisted of over 20% organics, similar to eastern blackwater rivers. The Kissimmee River is unique in North America for its hybrid alluvial/blackwater nature. Fluvial suspended‐sediment measurements for the three flood events indicate that a majority of the sediment (70%) was sand, which is important for natural levee construction. Of the total suspended sediment load for the three flood events, 3%–16% was organic and important in floodplain deposition. Sediment yield is similar to low‐gradient rivers draining to the Chesapeake Bay and alluvial rivers of the southeastern USA. Continued monitoring should determine whether observed sediment transport and floodplain deposition rates are normal for this river and determine the relationship between historic vegetation community restoration, hydroperiod restoration, and sedimentation. Published in 2011 by John Wiley & Sons, Ltd.

Book Reviews

Book Reviews

Unrealized Expectations for Restoration of a Floodplain Plant Community

The ongoing restoration of the channelized Kissimmee River is expected to promote reestablishment of the prolonged, deep inundation regimes that sustained broadleaf marsh as the dominant wetland plant community on the historical floodplain. The success of the restoration was evaluated at locations on the remnant floodplain where broadleaf marsh had been replaced by a mesophytic shrub community, and on the lower portion of the reconstructed floodplain, which was recreated by backfilling of a flood control canal and degradation of associated spoil mounds. During the 8-year post-restoration period (2001–2008) mean annual hydroperiods and depths on the restored floodplain were not significantly different from pre-channelization hydrologic conditions at historical reference sites. Increased hydroperiods and depths eliminated the mesophytic shrub (primarily Myrica cerifera) and associated fern cover, and led to colonization of floating and mat-forming species, but did not result in the reestablishment of a broadleaf marsh community. Signature broadleaf marsh species, Sagittaria lancifolia and Pontederia cordata, were found in all remnant floodplain plots and colonized 8 of the 10 reconstructed floodplain plots, but had mean cover ranging from only 0.9 to 6.1%. Several factors may have contributed to unsuccessful reestablishment of broadleaf marsh, including unfavorable edaphic conditions, brief drawdown (low stage) periods for establishment of seedlings, flood induced mortality, and an invasion of the exotic shrub, Ludwigia peruviana, which had post-restoration mean cover of 17–19%. Study results indicate hydrologic restoration of floodplain plant communities can be influenced by more discrete aspects of the river flood pulse than average hydroperiods and depths.

Restoration Response of Relict Broadleaf Marshes to Increased Water Depths

Broadleaf marsh once covered much of the wetland landscape along the Kissimmee River in central Florida, USA, but is currently restricted to remnant portions of the channelized floodplain that have been subjected to much shallower depths. The initial phase of Kissimmee River restoration, which began in 1999, and a prior (1984–1990) demonstration project increased water depths in several relict broadleaf marshes on the floodplain. Effects of restored water depth regimes on characteristics of these altered broadleaf marsh communities were evaluated. As expected, plant species richness consistently declined in marshes with increased water depth, but cover of signature broadleaf species, Sagittaria lancifolia and Pontederia cordata, exhibited variable responses to restored hydrology. In one marsh mean cover of Sagittaria and Pontederia increased from 32 to 62% following a 37 cm increase in mean annual depths; however, in another relict marsh that underwent a similar increase in hydroperiods and depths, mean cover of these species remained below 30% and Panicum hemitomon persisted as a dominant species. Moreover, invasion of the exotic wetland shrub, Ludwigia peruviana, appears to pose a threat to successful restoration of broadleaf marshes on the Kissimmee floodplain.

Ecosystem‐Based Management: What Really Happens?

Ecosystem‐Based Management: What Really Happens?

Potential Propagule Sources for Reestablishing Vegetation on the Floodplain of the Kissimmee River, Florida, USA

Potential Propagule Sources for Reestablishing Vegetation on the Floodplain of the Kissimmee River, Florida, USA

Potential propagule sources for reestablishing vegetation on the floodplain of the Kissimmee River, Florida, USA

After channellization of the Kissimmee River, the primary land use of the drained floodplain was cattle pasture but included sod farms. A project to restore the river began in 1999. One of its goals is to reestablish the three dominant, pre-channelization vegetation types (wetland shrub, broadleaf marsh, and wet prairie) in areas where they previously were found. We investigated whether indicator species of these three vegetation types were present in 53 permanent quadrats on the drained floodplain. All seven indicator species were found in the permanent quadrats. We also examined three potential sources of propagules (relict wetlands, seed banks, and several surrogates of hydrochory) for these indicator species. All seven species were found in adjacent relict wetlands; and six were found in the seed banks of permanent quadrats. Based on binomial logistic regressions, the presence of relict wetlands and surrogates for flooding (relative elevation, total days flooded) can predict the presence or absence of most of these indicator species. Sod farming reduced the presence of wet-prairie and broadleaf marsh indicator species in permanent quadrats, in adjacent relict wetlands and in the seed bank. The potential importance of relict wetlands for the re-vegetation of the floodplain was our most important finding.

Linking GIS, Hydraulic Modeling, and Tabu Search for Optimizing a Water Level-Monitoring Network in South Florida

The South Florida Water Management District (SFWMD) has a large and expanding surface water level-monitoring network for various water bodies including lakes and streams. SFWMD seeks to optimize the existing network of monitoring stations to collect the data from the least number of monitoring stations in the best possible locations without compromising information. Tabu combinatorial search algorithm is used to optimize water level-monitoring stations in lakes and streams within the SFWMD. Given a network of n stations, the methodology involves searching for the best spatial combination of r (where r<n) monitoring stations within the existing network to estimate water surface levels in lakes and streams within a given tolerance. Separate techniques are used to compute water levels in lakes and streams to compare possible solutions from Tabu search with observed daily data. Results from application of proposed techniques to Kissimmee River basin show that implementation of Tabu search within geographic information system (GIS) provides a computationally efficient way of optimizing a water level-monitoring network. It is also found that factors such as length of data records, slope of hydraulic profiles, and data at control structures play a significant role in the overall optimization process. The proposed methodology can also be used in the design of new monitoring networks and other water resources applications that involve GIS, computational modeling, and optimization.

Judith A. Layzer (Ed): Natural Experiments: Ecosystem-Based Management and the Environment

Ecosystem-based approaches (EBM) to natural resource management are at the forefront of progressive science and policy discussions. This holistic approach is inherently multi-dimensional. Managers and decision-makers must orient their view to all components of an ecosystem, including human interests. Three key underlying principles of EBM include landscape-scale planning that is intentionally collaborative (trans-jurisdiction/trans-sector) with an experimental, adaptive nature. The common single sector approach attends to human activities each in isolation from one another. This approach fails to address, much less maintain, the integrity of the interactions between the management sectors. This leads to a loss of valued ecosystem goods and services and ignorance about fundamental ecological and socio-economic linkages. Through a systematic empirical analysis, this book investigates the ways, and extent to which, seven cases throughout the US employ the three principles above with a goal of understanding whether the promise of EBM theory is effective in practice. Specifically, the author seeks to understand the circumstances that facilitate innovative management practices whose policies “conserve and restore ecosystem health.” Through a “focused comparison method,” evidence of environmental improvements, such as habitat restoration and species conservation, is assessed. Informed judgments are made to determine the ways in which the three principles of EBM affect each case’s outcomes. The first two chapters are contextual in that they place the author’s research aims among scholars’ arguments for and against an EBM approach. This results in both an optimistic and pessimistic model of EBM. These models serve as a baseline from which the author systematically assesses the evidence from each case. The optimistic approach praises EBM aspirations of bringing together otherwise disparate interests to create place-based plans and policies. The intended adaptive and flexible nature of these types of collaborations are hailed as one that promotes individual and institutional learning leading to improved management systems. The pessimistic approach cautions that the inertia infiltrating existing management is stronger than the willingness to create change. In addition, this model holds that stakeholder collaboration will not necessarily lead to consensus and shared goals. Rather, representatives will unknowingly uphold the status quo, act independently, and use power struggles to maintain sectorbased interests. The next seven chapters are each devoted to a case study, all of which have been acknowledged as initiatives experimenting with implementation of EBM principles. Cases include internationally-recognized initiatives and are grouped by terrestrial examples (Austin’s Balcones Canyonlands Conservation Program, San Diego Multiple Species Program) and aquatic examples (Comprehensive Everglades Restoration Plan, California Bay Delta Program), or are studied for comparison (Arizona Sonoran Desert Conservation Plan, Florida’s Kissimmee River, California Mono Basin). Some follow a more optimistic model of EBM with unintended benefits such as the development of innovative models that provoke thinking about the social and natural interrelationships of a system. Some cases are more in-line with the pessimistic model and have unintended consequences such as the disappointing Hum Ecol (2009) 37:251–252 DOI 10.1007/s10745-009-9229-2

Comparison of NEXRAD and Rain Gauge Precipitation Measurements in South Florida

The South Florida Water Management District (SFWMD) relies on a network of nearly 300 rain gauges in order to provide rainfall data for use in operations, modeling, water supply planning, and environmental projects. However, the prevalence of convective and tropical disturbances in South Florida during the wet season presents a challenge in that the current rain gauge network may not fully capture rain events that demonstrate high spatial variability. Next Generation Radar (NEXRAD) technology offers the advantage of providing a spatial account of rainfall, although the quality of radar-rainfall measurements remains largely unknown. The comparison of rainfall estimates from a gauge-adjusted, NEXRAD-based product developed by the OneRain Company with precipitation measurements from SFWMD rain gauges was performed for the Upper and Lower Kissimmee River Basins over a four-year period from 2002 to 2005. Overall, NEXRAD was found to underestimate rainfall with respect to the rain gauges for the study period, d...

Wetland Restoration Response Analysis using MODIS and Groundwater Data.

Vegetation cover and groundwater level changes over the period of restorationare the two most important indicators of the level of success in wetland ecohydrologicalrestoration. As a result of the regular presence of water and dense vegetation, the highestevapotranspiration (latent heat) rates usually occur within wetlands. Vegetation cover andevapotranspiration of large areas of restoration like that of Kissimmee River basin, SouthFlorida will be best estimated using remote sensing technique than point measurements.Kissimmee River basin has been the area of ecological restoration for some years. Thecurrent ecohydrological restoration activities were evaluated through fractional vegetationcover (FVC) changes and latent heat flux using Moderate Resolution ImagingSpectroradiometer (MODIS) data. Groundwater level data were also analyzed for selectedeight groundwater monitoring wells in the basin. Results have shown that the averagefractional vegetation cover and latent heat along 10 km buffer of Kissimmee River betweenLake Kissimmee and Lake Okeechobee was higher in 2004 than in 2000. It is evident thatover the 5-year period of time, vegetated and areas covered with wetlands have increasedsignificantly especially along the restoration corridor. Analysis of groundwater level data(2000-2004) from eight monitoring wells showed that, the average monthly level ofgroundwater was increased by 20 cm and 34 cm between 2000 and 2004, and 2000 and2003, respectively. This change was more evident for wells along the river.

Continuity in a changing environmental discourse: film depictions of Corps of Engineers projects in South Florida

The U.S. Army Corps of Engineers has undergone an apparent shift from an agency frequently accused of degrading environments to one that now embraces ecological restoration as a primary mission. Through a review of promotional films from the 1950s to the present, this paper assesses the changing ways in which the Corps and their partner resource management agencies represent their activities in the South Florida ecosystem, including the Everglades and Kissimmee River. I assess this paradigm shift in resource management from a feminist perspective illuminating continuities in depictions of science and technology-based ecological interventions. Based on this analysis I suggest that appeals to certainty of knowledge and technological control persist across time despite a shift in managerial ecology toward acknowledging imperfect knowledge and the unintended consequences of technological intervention.

Response of river metabolism to restoration of flow in the Kissimmee River, Florida, U.S.A.

Summary1. The single station diel oxygen curve method was used to determine the response of system metabolism to backfilling of a flood control canal and restoration of flow through the historic river channel of the Kissimmee River, a sub‐tropical, low gradient, blackwater river in central Florida, U.S.A. Gross primary productivity (GPP), community respiration (CR), the ratio of GPP/CR (P/R) and net daily metabolism (NDM) were estimated before and after canal backfilling and restoration of continuous flow through the river channel.2. Restoration of flow through the river channel significantly increased reaeration rates and mean dissolved oxygen (DO) concentrations from &lt;2 mg L−1 before restoration of flow to 4.70 mg L−1 after flow was restored.3. Annual GPP and CR rates were 0.43 g O2 m−2 day−1 and 1.61 g O2 m−2 day−1 respectively, before restoration of flow. After restoration of flow, annual GPP and CR rates increased to 3.95 O2 m−2 day−1 and 9.44 g O2 m−2 day−1 respectively.4. The ratio of P/R (mean of monthly values) increased from 0.29 during the prerestoration period to 0.51 after flow was restored, indicating an increase in autotrophic processes in the restored river channel. NDM values became more negative after flow was restored.5. After flow was restored, metabolism parameters were generally similar to those reported for other blackwater river systems in the southeast U.S.A. Postrestoration DO concentrations met target values derived from free flowing, minimally impacted reference streams.

Internal Nutrient Loads from Sediments in a Shallow, Subtropical Lake

Fluxes of dissolved inorganic nitrogen, DIN, (as ammonia, NH4-N) and phosphorus (as dissolved reactive phosphorus, DRP) from the sediments to the water column of Lake Okeechobee were determined from two separate techniques: increases in nutrient concentration in the water column above intact cores and concentration gradients determined with pore water equilibrators. These fluxes were estimated from different sediment types within the lake (sand, peat, mud) and at two major inflows (Kissimmee River and Taylor Creek). DRP release from peat sediments was highest. Measurements in other sediments were not significantly different from each other. DRP flux to the lake was estimated as 326 Mt·yr−1 in 1989 and had increased to 472 Mt·yr−1 in 1999. Because of measurement variation, this increase was not statistically different. These estimates of internal DRP loads are greater than estimated external surface DRP loads that averaged 316 Mt·yr−1 from 1979–1988 and 258 Mt·yr−1 from 1989−1999. DIN flux was highest near Taylor Creek. There was no consistent pattern between sediment type and DIN flux. Internal loads of DIN were estimated in 1999 as 4,500 Mt·yr−1, which is greater than the external surface loads of DIN estimated for the period of 1989–1998, of 896 Mt·yr−1. Sediment oxygen demand measured in the cores was strongly correlated to DRP and DIN flux, indicating that these fluxes are largely a result of mineralization of organic material. This study indicates that sediment diffusive fluxes are a significant source of DRP and DIN to the lake water column.

Plant Community Structure and Temporal Variability in a Channelized Subtropical Floodplain

Species composition, cover, diversity, and temporal dynamics of the three main plant communities in the channelized Kissimmee River floodplain were evaluated to provide a baseline for tracking the success of an ongoing restoration project. Much of the drained floodplain supports an upland herbaceous community with cover dominated by the planted pasture grasses Paspalum notatum and Axonopus fissifolius. Mesophytic woody communities are comprised primarily of Myrica cerifera, Baccharis halimifolia, Ludwigia peruviana, and understory ferns, while Sagittaria lancifolia, Pontederia cordata, and Panicum hemitomon are dominant species in remnant wetland communities. Community composition and the associated gradient of weighted averages of wetland indicator species reflect prevailing hydroperiods and land uses on the drained floodplain. Managed hydrologic regimes have promoted temporal stability, with seasonal variability of plant community characteristics limited to a decline in live plant cover and species richness during winter months. Lower live vegetation cover during winter resulted from senescence of dominant herbaceous species, while the winter decline in species richness was due primarily to sampling error resulting from seasonal phenology of taxonomic characteristics and obscured growth of rare or diminutive species. The limited variability of plant community characteristics in the channelized floodplain reduces the potential for confounding uncertainty in evaluating successful restoration. Results indicate that functional assessment of plant community characteristics in this subtropical floodplain is most accurately measured in spring and summer.

Abundance and Community Composition of Waterbirds Using the Channelized Kissimmee River Floodplain, FL

We conducted aerial surveys during 1996–1998 to estimate abundance and species composition of waterbirds using the channelized Kissimmee River to help understand how river channelization has altered bird use. For waterfowl, mean monthly species richness was 1.5 ± 0.3 (mean ± SE, n = 11 surveys); mean monthly abundance was 86 ± 43, 191 ± 70, and 13 ± 16 birds in 1996–97, 1997–98, and 1998–99, respectively. Blue-winged Teal (Anas discors Linnaeus) were the most abundant duck (74%) followed by Mottled Ducks (Anas fulvigula Ridgway, 21%). Mean wading bird species richness was 8.48 ± 0.35 (n = 20 surveys). Cattle Egret (Bubulcus ibis Linnaeus) were the most abundant wading bird species during the wet season (64 ± 22% of individuals); White Ibis (Eudocimus albus Linnaeus) were most common during the dry season (39 ± 23%). Mean total wading bird abundance was greater during the wet than dry season (F1,15 = 6.29; P = 0.02), with the increase driven by increases in Cattle Egret (F1,15 = 5.46, P = 0.03) and large-prey visual foragers (F1,15 = 5.47, P = 0.03). Compared to the 1950s, waterfowl species richness has declined 70% and abundance has declined 95%. For wading birds, mixed species breeding colonies no longer occur in the floodplain, and the community composition is dominated by the largely terrestrial foraging Cattle Egret during the wet season.

Phase I of the Kissimmee River restoration project, Florida, USA: Impacts of construction on water quality

Phase I of the Kissimmee River restoration project included backfilling of 12 km of canal and restoring flow through 24 km of continuous river channel. We quantified the effects of construction activities on four water quality parameters (turbidity, total phosphorus flow-weighted concentration, total phosphorus load and dissolved oxygen concentration). Data were collected at stations upstream and downstream of the construction and at four stations within the construction zone to determine if canal backfilling and construction of 2.4 km of new river channel would negatively impact local and downstream water quality. Turbidity levels at the downstream station were elevated for approximately 2 weeks during the one and a half year construction period, but never exceeded the Florida Department of Environmental Protection construction permit criteria. Turbidity levels at stations within the construction zone were high at certain times. Flow-weighted concentration of total phosphorus at the downstream station was slightly higher than the upstream station during construction, but low discharge limited downstream transport of phosphorus. Total phosphorus loads at the upstream and downstream stations were similar and loading to Lake Okeechobee was not significantly affected by construction. Mean water column dissolved oxygen concentrations at all sampling stations were similar during construction.

Possible artificial introductions of freshwater peritrich ciliates and their implications for assessment of protistan biodiversity

The planktonic, sessiline peritrichs Epicarchesium pectinatum (Zacharias 1897) and Pelagovorticella natans (Fauré‐Fremiet 1924) were collected from different tributaries of the St. Lucie River, Florida. Epistylis procumbens Zacharias, 1897, another planktonic sessiline, was collected near the mouth of the Kissimmee River, Florida. Epicarchesium pectinatum and P. natans were not seen again in the St. Lucie drainage, probably because prolonged drought had increased the salinity of habitats drastically. Epistylis procumbens was absent from other, nearby sections of the Kissimmee River and nearby lakes and streams. Efforts to collect the three species from other bodies of water in Florida and from lakes and ponds in central New York met with no success; however, P. natans was found in two of the many localities sampled in North Carolina, an artificial pond and a natural lake. Pelagovorticella natans was found on only one of several visits to the latter locality. The three species occurred in habitats that were either within or near populated areas and had been extensively modified. This and the disjunct, ephemeral distributions of the peritrichs suggest that they may have been introduced artificially. Artificial introduction of ciliates or other protists is poorly documented but probable, considering their small size and consequent ease of transportation, and peritrichs should be especially suspect because many of them attach to aquatic plants. In the end, research on biodiversity of free‐living protists must include the possibility of artificial introductions and develop methodologies to separate them from natural occurrences or else be reduced to a meaningless exercise.

Nests and Nest Habitats of the Invasive Catfish Hoplosternum littorale in Lake Tohopekaliga, Florida: A Novel Association with Non-native Hydrilla verticillata

Hoplosternum littorale is a South American catfish (Family Callichthyidae) first discovered in the United States in 1995 in Florida. The presence of H. littorale was documented from early 2002 to late 2003 in Lake Tohopekaliga (Kissimmee River Basin) in central Florida. In this paper, 22 H. littorale nests and nest sites are described. The characteristic bubble nests were present from late May to early September, with number of nests peaking in August when water stage and temperature were both high. Nest habitats (shallow, open marshes) and timing of nest construction (rainy season) were similar to what has been reported for H. littorale in its native range. Most nests (n = 14) were in areas dominated by Hydrilla verticillata and constructed largely from parts of this Asian aquatic plant, representing a unique association between two non-native species. Nevertheless, during August, as water levels increased, nesting shifted from H. verticillata-dominated communities to use of inshore grass zones dominated by Luziola fluitans. Knowledge of H. littorale nesting seasonality and habitat preferences may be useful for any efforts to control or manage this invasive fish.

Spatially distributed storm runoff depth estimation using Landsat images and GIS

The use of geographic information systems (GISs) and remote sensing to facilitate the estimation of runoff from watershed and agricultural fields has gained increasing attention in recent years. This is mainly due to the fact that rainfall-runoff models include both spatial and geomorphologic variations. The US Department of Agriculture, Natural Resources Conservation Service Curve Number (USDA-NRCS-CN) method was used in this study for determining the runoff depth. Runoff curve number was determined based on the factors of hydrologic soil group, land use, land treatment, and hydrologic conditions. GIS and remote sensing were used to provide quantitative measurements of drainage basin morphology for input into runoff models so as to estimate runoff response. The study was conducted on the S-65A sub-basin of the Kissimmee River basin in south Florida. Land use from Landsat images for 1980, 1990 and 2000 were considered in the study. The process of determining spatially distributed runoff curve numbers from Landsat images is presented in this study using GIS and image processing software. Spatially distributed runoff curve numbers and runoff depth were determined for the watershed for different land use classes. Results of the study show that land use changes determined from Landsat images are useful in studying the runoff response of the basin. It is shown that the S-65A sub-basin has undergone land use and runoff response changes over the 20 years period of time. The area covered by water and wetlands in 2000 is higher than in 1980 and 1990. In 2000 areas having CN of greater than 90 accounted for 3% compared to 0.9 and 0.6% in 1980 and 1990 respectively. This was due to the increase in wetlands and water covered areas attributed to the Kissimmee River restoration work, which started in 1997 and aimed at restoring lost wetlands and floodplains.