Review of the Lake Ontario-St. Lawrence River Studies (2006) / Chapter Skim
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4 Environmental Sciences in the LOSLR Study: Wetlands, Species at Risk, and the Integrated Ecological Response Model
4 Environmental Sciences in the LOSLR Study: Wetlands, Species at Risk, and the Integrated Ecological Response Model
Pages 89-117
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From page 89... ...
. In response to these and other environmental concerns and as part of an updated plan for water-level and flow regulation, a guiding principle of the IJC Study Board was that "Criteria and Regulation Plans will contribute to the ecological integrity of the Lake Ontario-St.
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From page 90... ...
· SAR 2 Lake Ontario Species at Risk Supplement (Least Bittern and Black Tern Reproductive Index Performance Indicators) · SAR 3A Impact of Water Level Regulation on Nearshore Habitat Availability and SAR · SAR 3B (Supplement)
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From page 91... ...
These inventories were repeated in 32 sites around Lake Ontario. The field research appropriately partitioned the sampling site selection across four common hydrogeomorphic wetland types of the Great Lakes: open embayment, protected embayment, barrier beach, and drowned river mouth.
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From page 92... ...
Criterion 1: Empirical Foundations Empirical foundations of the environmental sciences form the basis for faunal sub-models, environmental Performance Indicators, and ultimately environmental tradeoffs in the SVM. They are discussed in terms of wetland sampling, SAR sampling, missing empirical data, performance indicators, and the ecosystem v.
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From page 93... ...
A thorough analysis of the wetland study should document how well the sampled sites represent wetlands across Lake Ontario and the St. Lawrence River By consistently sampling only four of each wetland type in each country, the study may have inadvertently biased results in favor of open and protected embayments (see Table 4-1)
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From page 94... ...
Numbers in bracket are percent (%) of total wetlands in all of Lake Ontario, or only in the Canadian or U.S.
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From page 95... ...
b) FIGURE 4-1 Distribution of wetlands by geomorphic types in Lake Ontario and the St.
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From page 96... ...
Intuitively, excluding species from analysis would seem correct; however, this may prove to be a shortsighted choice since a stated purpose in developing a new water regulation plan is to reduce environmental degradation due to water level management and, presumably, restore some missing species. Certainly, it is more difficult to predict responses to water level management for species which have not been observed in the study area, but this may be no greater a limitation than reliance on only a handful of observations, which is already the case for some of the SAR for which Performance Indicators have been developed.
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From page 97... ...
Failure to include barrier beaches and dunes misses an opportunity to consider species and habitats associated with them, particularly along the southern coast of Lake Ontario, where loss of barrier beaches and dunes will also jeopardize wetlands that are presently protected by them.
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From page 98... ...
Units E1 Vegetation Wetland Meadow Marsh Communitytotal ha surface area and supply based (Lake Ontario) E2 Fish Low Veg 18C spawning habitat supply ha-days (Lake Ontario)
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From page 99... ...
In the illustrative case of the SAR Performance Indicators, it is sensible to reduce the original list of Performance Indicators to concentrate on those most likely to be affected by water level regulation, and then to narrow that list further to retain as indicators SAR that can "represent" a suite of other species expected to respond similarly. However, the criteria used to reduce the lists at each stage need to be stated more explicitly.
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From page 100... ...
The environmental Performance Indicators were designed to allow relative rankings of plan alternatives (ordinal measurement scale) rather than to predict absolute levels of SAR population responses to water level regulation (ratio measurement scale)
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From page 101... ...
This hypothesis needs to be experimentally verified to complete the wetland investigations. This verification is keenly needed because there is published evidence to the opposite effect: cattail distribution has been shown to increase with low water levels in Cootes Paradise Marsh, a large urban marsh at the western end of Lake Ontario (Chow-Fraser 2005; Wei and ChowFraser 2005; 2006)
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From page 102... ...
SAR Performance Indicator models refer to "rapid" rises in water levels, but "rapid" is not defined. Likewise, "stranded" is used in the wetlands documentation, but needs further clarification, in terms of how stranding occurs under different water level scenarios and how these impact species of interest, such as the northern pike.
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From page 103... ...
Such contradictory assessments illustrate the need for well-defined and consistent standards for judging reliability, especially when those judgments are qualitative. It is helpful to comment on the sensitivity of the SAR Performance Indicators to water level regulation, as is done in the appendices to SAR 3A for at least some SAR.
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From page 104... ...
Because decisions about water level regulation will be based, in part, upon the environmental sciences information, the IJC needs a high level of confidence in the conclusions derived from the myriad of models produced. The environmental sciences work presents an illustrative example of how error could be introduced and propagated throughout the LOSLR study structure.
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From page 105... ...
Wetland researchers should collaborate with the shoreline modelers to develop bathymetric scenarios for wetland sites. The protected barrier beach wetlands of Lake Ontario comprise a major hydrogeomorphic community and are included in the wetland empirical work, but not integrated into the FEPS, IERM, or SVM models.
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From page 106... ...
Lawrence River Hourly Water Levels about the Quarter-Monthly Mean, pages 8 and 9) point out that river level variation can be quite high during the spring freshet: "at Betancour, the daily level typically varies within + 25cm from its quarter-monthly level, but can be as much as 80 cm higher or 50 cm lower year round." At Batiscan, daily levels can be 100cm higher or 70 cm lower than quarter monthly estimates.
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From page 107... ...
Individual results of environmental Performance Indicators respond differently to variations in water regulation plans, and a single index will obscure these differences. Perhaps this concern is best illustrated by the example of the Moses Saunders dam.
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From page 108... ...
Three evaluation criteria are used to address this charge: the study scope and aims, balance between scientific and practical professional judgment, and future needs to respond to effects of water level regulation on multi-decadal time scale. Criterion 8: Breadth of Study Scope One of the impressive aspects of the LOSLR study is its inclusion of environmental considerations in selecting a water regulation plan.
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From page 109... ...
Because these other factors that are likely to influence SAR and other environmental Performance Indicators have not been included in any of the Performance Indicator models, it will be very difficult to use monitoring data to evaluate the success of water regulation plans and to update and improve the Performance Indicator models. There are likely to be variations in environmental status attributable to these or other factors in addition to or instead of water level fluctuations.
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From page 110... ...
incorporating factors other than water levels in data collection and modeling via an adaptive management scheme, and (3) validation and improvement of Performance Indicator models.
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From page 111... ...
While applauded for the extensive database populated by the wetlands sampling inventories, the wetlands empirical work presents some concerns: · The current sampling methods limited to shallow waters excluded or undersampled many of the submergent species in the high-quality wetlands and likely underestimated the diversity of submerged vegetation and available fish habitat · The 32 "typical" wetland sites selected for sampling may not be representative of Lake Ontario-St. Lawrence River wetlands, as these sites were neither chosen randomly nor sampled to ensure representativeness of available wetland types.
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From page 112... ...
The main findings about and recommendations for improving the IERM follow: · Performance Indicator ratios are calculated differently, based on different units, such as biomass, area, and other measures, and should be reconciled to calculate ratios in a consistent, comparable, and coherent manner · An explanation is needed about how Performance Indicators were selected or eliminated for use in the IERM and SVM · Better documentation is needed about how limitations of certainty and propagation of error are calculated, including clarification of or a quantitative substitute for the 10 percent rule that was derived from a Study Board's "administrative decision" · The Performance Indicator for barrier beaches should be included in the IERM · The Index of Ecological Integrity used in the LOSLR Study presents a single value that (1) obscures differences among environmental Performance Indicators and (2)
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From page 113... ...
Currently, this environmental work is compromised by unanswered questions in the wetlands sampling methodologies and inadequate documentation that ultimately undermines confidence that linkages among environmental Performance Indicators, IERM model and its sub-models, and the SVM operate as designed. Several issues need to be addressed in order to elevate the environmental work to the level of being appropriate and sufficient to inform the water regulation plan decision making process.
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From page 114... ...
Lawrence River Hourly Water Levels About the Quarter-Monthly Mean. Hydrology and Hydraulics Technical Working Group.
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From page 115... ...
1984. The effects of natural water level fluctuations on N and P cycling in a Great Lakes marsh.
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From page 116... ...
2005. Untangling the confounding effects of ur banization and high water level on the cover of emergent vegetation in Cootes Paradise Marsh, a degraded coastal wetland of Lake Ontario.
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From page 117... ...
2003. Year 3 Report of Relationship between Lake Ontario Water Levels and the Wetlands.
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