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The concept of alternate stable states is important in ecological theory and models, but the application and implementation of these models have the potential to make significant future advances in the field of patterned landscapes. The bistable ridge and slough landscape is a central feature of Everglades restoration and provides an important opportunity to test stable state theory with multistate transition models. We used these models to estimate environmental parameters associated with state changes (water depths, edaphic factors, etc.) and develop a quantitative method to measure resilience and stability. The multistate model indicates that long‐term, local hydrology (15‐yr mean maximums and 15‐yr mean amplitude) and edaphic factors control the local scale shifts between ridge and slough states. We show that multistate models can provide hydrologic envelopes for managers, produce a tool to help assess future water management scenarios, and address issues of sustainability, resilience, and restoration for any bistable system. [ABSTRACT FROM AUTHOR]

Patterned landscapes have long been a popular setting to test hypotheses about the effects of processes on ecosystem structure. The combination of scale-dependent and positive feedback theory is one of the most well-supported in current literature, each explaining separate aspects of patterned peatlands. These theories have been developed from dynamics in boreal peatlands and tested in boreal systems, but the mechanisms that control peat patterning in a sub-tropical system have yet to be acknowledged in theory. Statistical evidence for different mechanisms are present in the biophysical features of sub-tropical patterned peatlands, such as the ridge and slough landscape (RSL) within the greater Everglades wetland system. We use data from the RSL to test whether features of a sub-tropical, patterned peatland conform to positive and scale-dependent feedback patterning theories developed in boreal peatlands and use dynamic simulation to explain our results. The analysis of surface elements and nutrient differences within the RSL and our dynamic simulations indicate that positive and scale-dependent feedback may not be appropriate theories for sub-tropical peat patterning. Decomposition, rather than production, appears to be more important for abrupt microtopographical elevation differences, and differential nutrient concentrations are due to vegetation types, rather than increased evapotranspiration from greater vascular plant growth. Our model expands on the current theories for RSL maintenance, incorporating vegetation types and life history traits into differential peat deposition, which create the signature microtopographical differences found in the Everglades, and demonstrates that the underlying ecological patterning processes in sub-tropical peatlands are likely very different from boreal peatlands and require further discussion and study. [ABSTRACT FROM AUTHOR]

The spread of invasive species is a global problem of major ecological and economic concern. Landscape level assessment of invasive spread is critical, but remote sensing ( RS) analyses are often complicated by the spectral similarity of species and the need to balance spatial resolution with data storage and analysis complexity. One example is the ridge and slough landscape ( RSL) of the Florida Everglades, where inflowing nutrients have facilitated large-scale cattail invasions. Hand delineation of aerial imagery has been successful in mapping cattail spread, but this technique requires considerable time and effort. Computerized classification of medium-resolution imagery would increase the ability of scientists to provide up-to-date data for water management decisions. Advances in RS technologies have created opportunities that were not previously available in landscapes such as the RSL-to automatically classify sawgrass and cattail communities with medium-resolution satellite imagery using knowledge of the invasion ecology of cattail and landscape context. We developed a computer-classification technique that provided measure of cattail expansion that matched ground-truthed data and show an increase in cattail area (similar to previous estimates), but a reduction in the rate of expansion over time. Although this technique can miss small patches of plants that might indicated new invasions, its rapid mapping can improve tracking of invasion fronts in the Everglades and other landscapes. [ABSTRACT FROM AUTHOR]

The article focuses on a study for the evaluation of body condition indices for the American alligator. Topics discussed include effects of landscape and changes in hydrology on alligators; understanding the biological significance of the ANOVA results; and difference in the water management units for the condition of alligators.